2 * Copyright © 2014 Intel Corporation
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
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9 * Software is furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
24 * Ben Widawsky <ben@bwidawsk.net>
25 * Michel Thierry <michel.thierry@intel.com>
26 * Thomas Daniel <thomas.daniel@intel.com>
27 * Oscar Mateo <oscar.mateo@intel.com>
32 * DOC: Logical Rings, Logical Ring Contexts and Execlists
35 * GEN8 brings an expansion of the HW contexts: "Logical Ring Contexts".
36 * These expanded contexts enable a number of new abilities, especially
37 * "Execlists" (also implemented in this file).
39 * One of the main differences with the legacy HW contexts is that logical
40 * ring contexts incorporate many more things to the context's state, like
41 * PDPs or ringbuffer control registers:
43 * The reason why PDPs are included in the context is straightforward: as
44 * PPGTTs (per-process GTTs) are actually per-context, having the PDPs
45 * contained there mean you don't need to do a ppgtt->switch_mm yourself,
46 * instead, the GPU will do it for you on the context switch.
48 * But, what about the ringbuffer control registers (head, tail, etc..)?
49 * shouldn't we just need a set of those per engine command streamer? This is
50 * where the name "Logical Rings" starts to make sense: by virtualizing the
51 * rings, the engine cs shifts to a new "ring buffer" with every context
52 * switch. When you want to submit a workload to the GPU you: A) choose your
53 * context, B) find its appropriate virtualized ring, C) write commands to it
54 * and then, finally, D) tell the GPU to switch to that context.
56 * Instead of the legacy MI_SET_CONTEXT, the way you tell the GPU to switch
57 * to a contexts is via a context execution list, ergo "Execlists".
60 * Regarding the creation of contexts, we have:
62 * - One global default context.
63 * - One local default context for each opened fd.
64 * - One local extra context for each context create ioctl call.
66 * Now that ringbuffers belong per-context (and not per-engine, like before)
67 * and that contexts are uniquely tied to a given engine (and not reusable,
68 * like before) we need:
70 * - One ringbuffer per-engine inside each context.
71 * - One backing object per-engine inside each context.
73 * The global default context starts its life with these new objects fully
74 * allocated and populated. The local default context for each opened fd is
75 * more complex, because we don't know at creation time which engine is going
76 * to use them. To handle this, we have implemented a deferred creation of LR
79 * The local context starts its life as a hollow or blank holder, that only
80 * gets populated for a given engine once we receive an execbuffer. If later
81 * on we receive another execbuffer ioctl for the same context but a different
82 * engine, we allocate/populate a new ringbuffer and context backing object and
85 * Finally, regarding local contexts created using the ioctl call: as they are
86 * only allowed with the render ring, we can allocate & populate them right
87 * away (no need to defer anything, at least for now).
89 * Execlists implementation:
90 * Execlists are the new method by which, on gen8+ hardware, workloads are
91 * submitted for execution (as opposed to the legacy, ringbuffer-based, method).
92 * This method works as follows:
94 * When a request is committed, its commands (the BB start and any leading or
95 * trailing commands, like the seqno breadcrumbs) are placed in the ringbuffer
96 * for the appropriate context. The tail pointer in the hardware context is not
97 * updated at this time, but instead, kept by the driver in the ringbuffer
98 * structure. A structure representing this request is added to a request queue
99 * for the appropriate engine: this structure contains a copy of the context's
100 * tail after the request was written to the ring buffer and a pointer to the
103 * If the engine's request queue was empty before the request was added, the
104 * queue is processed immediately. Otherwise the queue will be processed during
105 * a context switch interrupt. In any case, elements on the queue will get sent
106 * (in pairs) to the GPU's ExecLists Submit Port (ELSP, for short) with a
107 * globally unique 20-bits submission ID.
109 * When execution of a request completes, the GPU updates the context status
110 * buffer with a context complete event and generates a context switch interrupt.
111 * During the interrupt handling, the driver examines the events in the buffer:
112 * for each context complete event, if the announced ID matches that on the head
113 * of the request queue, then that request is retired and removed from the queue.
115 * After processing, if any requests were retired and the queue is not empty
116 * then a new execution list can be submitted. The two requests at the front of
117 * the queue are next to be submitted but since a context may not occur twice in
118 * an execution list, if subsequent requests have the same ID as the first then
119 * the two requests must be combined. This is done simply by discarding requests
120 * at the head of the queue until either only one requests is left (in which case
121 * we use a NULL second context) or the first two requests have unique IDs.
123 * By always executing the first two requests in the queue the driver ensures
124 * that the GPU is kept as busy as possible. In the case where a single context
125 * completes but a second context is still executing, the request for this second
126 * context will be at the head of the queue when we remove the first one. This
127 * request will then be resubmitted along with a new request for a different context,
128 * which will cause the hardware to continue executing the second request and queue
129 * the new request (the GPU detects the condition of a context getting preempted
130 * with the same context and optimizes the context switch flow by not doing
131 * preemption, but just sampling the new tail pointer).
134 #include <linux/interrupt.h>
136 #include "i915_drv.h"
137 #include "i915_perf.h"
138 #include "i915_trace.h"
139 #include "i915_vgpu.h"
140 #include "intel_context.h"
141 #include "intel_engine_pm.h"
142 #include "intel_gt.h"
143 #include "intel_gt_pm.h"
144 #include "intel_gt_requests.h"
145 #include "intel_lrc_reg.h"
146 #include "intel_mocs.h"
147 #include "intel_reset.h"
148 #include "intel_ring.h"
149 #include "intel_workarounds.h"
151 #define RING_EXECLIST_QFULL (1 << 0x2)
152 #define RING_EXECLIST1_VALID (1 << 0x3)
153 #define RING_EXECLIST0_VALID (1 << 0x4)
154 #define RING_EXECLIST_ACTIVE_STATUS (3 << 0xE)
155 #define RING_EXECLIST1_ACTIVE (1 << 0x11)
156 #define RING_EXECLIST0_ACTIVE (1 << 0x12)
158 #define GEN8_CTX_STATUS_IDLE_ACTIVE (1 << 0)
159 #define GEN8_CTX_STATUS_PREEMPTED (1 << 1)
160 #define GEN8_CTX_STATUS_ELEMENT_SWITCH (1 << 2)
161 #define GEN8_CTX_STATUS_ACTIVE_IDLE (1 << 3)
162 #define GEN8_CTX_STATUS_COMPLETE (1 << 4)
163 #define GEN8_CTX_STATUS_LITE_RESTORE (1 << 15)
165 #define GEN8_CTX_STATUS_COMPLETED_MASK \
166 (GEN8_CTX_STATUS_COMPLETE | GEN8_CTX_STATUS_PREEMPTED)
168 #define CTX_DESC_FORCE_RESTORE BIT_ULL(2)
170 #define GEN12_CTX_STATUS_SWITCHED_TO_NEW_QUEUE (0x1) /* lower csb dword */
171 #define GEN12_CTX_SWITCH_DETAIL(csb_dw) ((csb_dw) & 0xF) /* upper csb dword */
172 #define GEN12_CSB_SW_CTX_ID_MASK GENMASK(25, 15)
173 #define GEN12_IDLE_CTX_ID 0x7FF
174 #define GEN12_CSB_CTX_VALID(csb_dw) \
175 (FIELD_GET(GEN12_CSB_SW_CTX_ID_MASK, csb_dw) != GEN12_IDLE_CTX_ID)
177 /* Typical size of the average request (2 pipecontrols and a MI_BB) */
178 #define EXECLISTS_REQUEST_SIZE 64 /* bytes */
179 #define WA_TAIL_DWORDS 2
180 #define WA_TAIL_BYTES (sizeof(u32) * WA_TAIL_DWORDS)
182 struct virtual_engine {
183 struct intel_engine_cs base;
184 struct intel_context context;
187 * We allow only a single request through the virtual engine at a time
188 * (each request in the timeline waits for the completion fence of
189 * the previous before being submitted). By restricting ourselves to
190 * only submitting a single request, each request is placed on to a
191 * physical to maximise load spreading (by virtue of the late greedy
192 * scheduling -- each real engine takes the next available request
195 struct i915_request *request;
198 * We keep a rbtree of available virtual engines inside each physical
199 * engine, sorted by priority. Here we preallocate the nodes we need
200 * for the virtual engine, indexed by physical_engine->id.
205 } nodes[I915_NUM_ENGINES];
208 * Keep track of bonded pairs -- restrictions upon on our selection
209 * of physical engines any particular request may be submitted to.
210 * If we receive a submit-fence from a master engine, we will only
211 * use one of sibling_mask physical engines.
214 const struct intel_engine_cs *master;
215 intel_engine_mask_t sibling_mask;
217 unsigned int num_bonds;
219 /* And finally, which physical engines this virtual engine maps onto. */
220 unsigned int num_siblings;
221 struct intel_engine_cs *siblings[0];
224 static struct virtual_engine *to_virtual_engine(struct intel_engine_cs *engine)
226 GEM_BUG_ON(!intel_engine_is_virtual(engine));
227 return container_of(engine, struct virtual_engine, base);
230 static int __execlists_context_alloc(struct intel_context *ce,
231 struct intel_engine_cs *engine);
233 static void execlists_init_reg_state(u32 *reg_state,
234 const struct intel_context *ce,
235 const struct intel_engine_cs *engine,
236 const struct intel_ring *ring,
239 __execlists_update_reg_state(const struct intel_context *ce,
240 const struct intel_engine_cs *engine,
243 static void mark_eio(struct i915_request *rq)
245 if (i915_request_completed(rq))
248 GEM_BUG_ON(i915_request_signaled(rq));
250 dma_fence_set_error(&rq->fence, -EIO);
251 i915_request_mark_complete(rq);
254 static struct i915_request *
255 active_request(const struct intel_timeline * const tl, struct i915_request *rq)
257 struct i915_request *active = rq;
260 list_for_each_entry_continue_reverse(rq, &tl->requests, link) {
261 if (i915_request_completed(rq))
271 static inline u32 intel_hws_preempt_address(struct intel_engine_cs *engine)
273 return (i915_ggtt_offset(engine->status_page.vma) +
274 I915_GEM_HWS_PREEMPT_ADDR);
278 ring_set_paused(const struct intel_engine_cs *engine, int state)
281 * We inspect HWS_PREEMPT with a semaphore inside
282 * engine->emit_fini_breadcrumb. If the dword is true,
283 * the ring is paused as the semaphore will busywait
284 * until the dword is false.
286 engine->status_page.addr[I915_GEM_HWS_PREEMPT] = state;
291 static inline struct i915_priolist *to_priolist(struct rb_node *rb)
293 return rb_entry(rb, struct i915_priolist, node);
296 static inline int rq_prio(const struct i915_request *rq)
298 return rq->sched.attr.priority;
301 static int effective_prio(const struct i915_request *rq)
303 int prio = rq_prio(rq);
306 * If this request is special and must not be interrupted at any
307 * cost, so be it. Note we are only checking the most recent request
308 * in the context and so may be masking an earlier vip request. It
309 * is hoped that under the conditions where nopreempt is used, this
310 * will not matter (i.e. all requests to that context will be
311 * nopreempt for as long as desired).
313 if (i915_request_has_nopreempt(rq))
314 prio = I915_PRIORITY_UNPREEMPTABLE;
317 * On unwinding the active request, we give it a priority bump
318 * if it has completed waiting on any semaphore. If we know that
319 * the request has already started, we can prevent an unwanted
320 * preempt-to-idle cycle by taking that into account now.
322 if (__i915_request_has_started(rq))
323 prio |= I915_PRIORITY_NOSEMAPHORE;
325 /* Restrict mere WAIT boosts from triggering preemption */
326 BUILD_BUG_ON(__NO_PREEMPTION & ~I915_PRIORITY_MASK); /* only internal */
327 return prio | __NO_PREEMPTION;
330 static int queue_prio(const struct intel_engine_execlists *execlists)
332 struct i915_priolist *p;
335 rb = rb_first_cached(&execlists->queue);
340 * As the priolist[] are inverted, with the highest priority in [0],
341 * we have to flip the index value to become priority.
344 return ((p->priority + 1) << I915_USER_PRIORITY_SHIFT) - ffs(p->used);
347 static inline bool need_preempt(const struct intel_engine_cs *engine,
348 const struct i915_request *rq,
353 if (!intel_engine_has_semaphores(engine))
357 * Check if the current priority hint merits a preemption attempt.
359 * We record the highest value priority we saw during rescheduling
360 * prior to this dequeue, therefore we know that if it is strictly
361 * less than the current tail of ESLP[0], we do not need to force
362 * a preempt-to-idle cycle.
364 * However, the priority hint is a mere hint that we may need to
365 * preempt. If that hint is stale or we may be trying to preempt
366 * ourselves, ignore the request.
368 * More naturally we would write
369 * prio >= max(0, last);
370 * except that we wish to prevent triggering preemption at the same
371 * priority level: the task that is running should remain running
372 * to preserve FIFO ordering of dependencies.
374 last_prio = max(effective_prio(rq), I915_PRIORITY_NORMAL - 1);
375 if (engine->execlists.queue_priority_hint <= last_prio)
379 * Check against the first request in ELSP[1], it will, thanks to the
380 * power of PI, be the highest priority of that context.
382 if (!list_is_last(&rq->sched.link, &engine->active.requests) &&
383 rq_prio(list_next_entry(rq, sched.link)) > last_prio)
387 struct virtual_engine *ve =
388 rb_entry(rb, typeof(*ve), nodes[engine->id].rb);
389 bool preempt = false;
391 if (engine == ve->siblings[0]) { /* only preempt one sibling */
392 struct i915_request *next;
395 next = READ_ONCE(ve->request);
397 preempt = rq_prio(next) > last_prio;
406 * If the inflight context did not trigger the preemption, then maybe
407 * it was the set of queued requests? Pick the highest priority in
408 * the queue (the first active priolist) and see if it deserves to be
409 * running instead of ELSP[0].
411 * The highest priority request in the queue can not be either
412 * ELSP[0] or ELSP[1] as, thanks again to PI, if it was the same
413 * context, it's priority would not exceed ELSP[0] aka last_prio.
415 return queue_prio(&engine->execlists) > last_prio;
418 __maybe_unused static inline bool
419 assert_priority_queue(const struct i915_request *prev,
420 const struct i915_request *next)
423 * Without preemption, the prev may refer to the still active element
424 * which we refuse to let go.
426 * Even with preemption, there are times when we think it is better not
427 * to preempt and leave an ostensibly lower priority request in flight.
429 if (i915_request_is_active(prev))
432 return rq_prio(prev) >= rq_prio(next);
436 * The context descriptor encodes various attributes of a context,
437 * including its GTT address and some flags. Because it's fairly
438 * expensive to calculate, we'll just do it once and cache the result,
439 * which remains valid until the context is unpinned.
441 * This is what a descriptor looks like, from LSB to MSB::
443 * bits 0-11: flags, GEN8_CTX_* (cached in ctx->desc_template)
444 * bits 12-31: LRCA, GTT address of (the HWSP of) this context
445 * bits 32-52: ctx ID, a globally unique tag (highest bit used by GuC)
446 * bits 53-54: mbz, reserved for use by hardware
447 * bits 55-63: group ID, currently unused and set to 0
449 * Starting from Gen11, the upper dword of the descriptor has a new format:
451 * bits 32-36: reserved
452 * bits 37-47: SW context ID
453 * bits 48:53: engine instance
454 * bit 54: mbz, reserved for use by hardware
455 * bits 55-60: SW counter
456 * bits 61-63: engine class
458 * engine info, SW context ID and SW counter need to form a unique number
459 * (Context ID) per lrc.
462 lrc_descriptor(struct intel_context *ce, struct intel_engine_cs *engine)
466 desc = INTEL_LEGACY_32B_CONTEXT;
467 if (i915_vm_is_4lvl(ce->vm))
468 desc = INTEL_LEGACY_64B_CONTEXT;
469 desc <<= GEN8_CTX_ADDRESSING_MODE_SHIFT;
471 desc |= GEN8_CTX_VALID | GEN8_CTX_PRIVILEGE;
472 if (IS_GEN(engine->i915, 8))
473 desc |= GEN8_CTX_L3LLC_COHERENT;
475 desc |= i915_ggtt_offset(ce->state); /* bits 12-31 */
477 * The following 32bits are copied into the OA reports (dword 2).
478 * Consider updating oa_get_render_ctx_id in i915_perf.c when changing
481 if (INTEL_GEN(engine->i915) >= 11) {
482 desc |= (u64)engine->instance << GEN11_ENGINE_INSTANCE_SHIFT;
485 desc |= (u64)engine->class << GEN11_ENGINE_CLASS_SHIFT;
492 static inline unsigned int dword_in_page(void *addr)
494 return offset_in_page(addr) / sizeof(u32);
497 static void set_offsets(u32 *regs,
499 const struct intel_engine_cs *engine,
501 #define NOP(x) (BIT(7) | (x))
502 #define LRI(count, flags) ((flags) << 6 | (count) | BUILD_BUG_ON_ZERO(count >= BIT(6)))
503 #define POSTED BIT(0)
504 #define REG(x) (((x) >> 2) | BUILD_BUG_ON_ZERO(x >= 0x200))
506 (((x) >> 9) | BIT(7) | BUILD_BUG_ON_ZERO(x >= 0x10000)), \
508 #define END(x) 0, (x)
510 const u32 base = engine->mmio_base;
515 if (*data & BIT(7)) { /* skip */
516 count = *data++ & ~BIT(7);
518 memset32(regs, MI_NOOP, count);
523 count = *data & 0x3f;
527 *regs = MI_LOAD_REGISTER_IMM(count);
529 *regs |= MI_LRI_FORCE_POSTED;
530 if (INTEL_GEN(engine->i915) >= 11)
531 *regs |= MI_LRI_CS_MMIO;
542 offset |= v & ~BIT(7);
543 } while (v & BIT(7));
545 regs[0] = base + (offset << 2);
555 /* Clear past the tail for HW access */
556 GEM_BUG_ON(dword_in_page(regs) > count);
557 memset32(regs, MI_NOOP, count - dword_in_page(regs));
559 /* Close the batch; used mainly by live_lrc_layout() */
560 *regs = MI_BATCH_BUFFER_END;
561 if (INTEL_GEN(engine->i915) >= 10)
566 static const u8 gen8_xcs_offsets[] = {
601 static const u8 gen9_xcs_offsets[] = {
685 static const u8 gen12_xcs_offsets[] = {
717 static const u8 gen8_rcs_offsets[] = {
754 static const u8 gen9_rcs_offsets[] = {
838 static const u8 gen11_rcs_offsets[] = {
879 static const u8 gen12_rcs_offsets[] = {
926 static const u8 *reg_offsets(const struct intel_engine_cs *engine)
929 * The gen12+ lists only have the registers we program in the basic
930 * default state. We rely on the context image using relative
931 * addressing to automatic fixup the register state between the
932 * physical engines for virtual engine.
934 GEM_BUG_ON(INTEL_GEN(engine->i915) >= 12 &&
935 !intel_engine_has_relative_mmio(engine));
937 if (engine->class == RENDER_CLASS) {
938 if (INTEL_GEN(engine->i915) >= 12)
939 return gen12_rcs_offsets;
940 else if (INTEL_GEN(engine->i915) >= 11)
941 return gen11_rcs_offsets;
942 else if (INTEL_GEN(engine->i915) >= 9)
943 return gen9_rcs_offsets;
945 return gen8_rcs_offsets;
947 if (INTEL_GEN(engine->i915) >= 12)
948 return gen12_xcs_offsets;
949 else if (INTEL_GEN(engine->i915) >= 9)
950 return gen9_xcs_offsets;
952 return gen8_xcs_offsets;
956 static struct i915_request *
957 __unwind_incomplete_requests(struct intel_engine_cs *engine)
959 struct i915_request *rq, *rn, *active = NULL;
960 struct list_head *uninitialized_var(pl);
961 int prio = I915_PRIORITY_INVALID;
963 lockdep_assert_held(&engine->active.lock);
965 list_for_each_entry_safe_reverse(rq, rn,
966 &engine->active.requests,
968 if (i915_request_completed(rq))
971 __i915_request_unsubmit(rq);
974 * Push the request back into the queue for later resubmission.
975 * If this request is not native to this physical engine (i.e.
976 * it came from a virtual source), push it back onto the virtual
977 * engine so that it can be moved across onto another physical
978 * engine as load dictates.
980 if (likely(rq->execution_mask == engine->mask)) {
981 GEM_BUG_ON(rq_prio(rq) == I915_PRIORITY_INVALID);
982 if (rq_prio(rq) != prio) {
984 pl = i915_sched_lookup_priolist(engine, prio);
986 GEM_BUG_ON(RB_EMPTY_ROOT(&engine->execlists.queue.rb_root));
988 list_move(&rq->sched.link, pl);
989 set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
993 struct intel_engine_cs *owner = rq->context->engine;
996 * Decouple the virtual breadcrumb before moving it
997 * back to the virtual engine -- we don't want the
998 * request to complete in the background and try
999 * and cancel the breadcrumb on the virtual engine
1000 * (instead of the old engine where it is linked)!
1002 if (test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT,
1003 &rq->fence.flags)) {
1004 spin_lock_nested(&rq->lock,
1005 SINGLE_DEPTH_NESTING);
1006 i915_request_cancel_breadcrumb(rq);
1007 spin_unlock(&rq->lock);
1010 owner->submit_request(rq);
1018 struct i915_request *
1019 execlists_unwind_incomplete_requests(struct intel_engine_execlists *execlists)
1021 struct intel_engine_cs *engine =
1022 container_of(execlists, typeof(*engine), execlists);
1024 return __unwind_incomplete_requests(engine);
1028 execlists_context_status_change(struct i915_request *rq, unsigned long status)
1031 * Only used when GVT-g is enabled now. When GVT-g is disabled,
1032 * The compiler should eliminate this function as dead-code.
1034 if (!IS_ENABLED(CONFIG_DRM_I915_GVT))
1037 atomic_notifier_call_chain(&rq->engine->context_status_notifier,
1041 static void intel_engine_context_in(struct intel_engine_cs *engine)
1043 unsigned long flags;
1045 if (READ_ONCE(engine->stats.enabled) == 0)
1048 write_seqlock_irqsave(&engine->stats.lock, flags);
1050 if (engine->stats.enabled > 0) {
1051 if (engine->stats.active++ == 0)
1052 engine->stats.start = ktime_get();
1053 GEM_BUG_ON(engine->stats.active == 0);
1056 write_sequnlock_irqrestore(&engine->stats.lock, flags);
1059 static void intel_engine_context_out(struct intel_engine_cs *engine)
1061 unsigned long flags;
1063 if (READ_ONCE(engine->stats.enabled) == 0)
1066 write_seqlock_irqsave(&engine->stats.lock, flags);
1068 if (engine->stats.enabled > 0) {
1071 if (engine->stats.active && --engine->stats.active == 0) {
1073 * Decrement the active context count and in case GPU
1074 * is now idle add up to the running total.
1076 last = ktime_sub(ktime_get(), engine->stats.start);
1078 engine->stats.total = ktime_add(engine->stats.total,
1080 } else if (engine->stats.active == 0) {
1082 * After turning on engine stats, context out might be
1083 * the first event in which case we account from the
1084 * time stats gathering was turned on.
1086 last = ktime_sub(ktime_get(), engine->stats.enabled_at);
1088 engine->stats.total = ktime_add(engine->stats.total,
1093 write_sequnlock_irqrestore(&engine->stats.lock, flags);
1096 static int lrc_ring_mi_mode(const struct intel_engine_cs *engine)
1098 if (INTEL_GEN(engine->i915) >= 12)
1100 else if (INTEL_GEN(engine->i915) >= 9)
1102 else if (engine->class == RENDER_CLASS)
1109 execlists_check_context(const struct intel_context *ce,
1110 const struct intel_engine_cs *engine)
1112 const struct intel_ring *ring = ce->ring;
1113 u32 *regs = ce->lrc_reg_state;
1117 if (regs[CTX_RING_START] != i915_ggtt_offset(ring->vma)) {
1118 pr_err("%s: context submitted with incorrect RING_START [%08x], expected %08x\n",
1120 regs[CTX_RING_START],
1121 i915_ggtt_offset(ring->vma));
1122 regs[CTX_RING_START] = i915_ggtt_offset(ring->vma);
1126 if ((regs[CTX_RING_CTL] & ~(RING_WAIT | RING_WAIT_SEMAPHORE)) !=
1127 (RING_CTL_SIZE(ring->size) | RING_VALID)) {
1128 pr_err("%s: context submitted with incorrect RING_CTL [%08x], expected %08x\n",
1131 (u32)(RING_CTL_SIZE(ring->size) | RING_VALID));
1132 regs[CTX_RING_CTL] = RING_CTL_SIZE(ring->size) | RING_VALID;
1136 x = lrc_ring_mi_mode(engine);
1137 if (x != -1 && regs[x + 1] & (regs[x + 1] >> 16) & STOP_RING) {
1138 pr_err("%s: context submitted with STOP_RING [%08x] in RING_MI_MODE\n",
1139 engine->name, regs[x + 1]);
1140 regs[x + 1] &= ~STOP_RING;
1141 regs[x + 1] |= STOP_RING << 16;
1145 WARN_ONCE(!valid, "Invalid lrc state found before submission\n");
1148 static void restore_default_state(struct intel_context *ce,
1149 struct intel_engine_cs *engine)
1151 u32 *regs = ce->lrc_reg_state;
1153 if (engine->pinned_default_state)
1154 memcpy(regs, /* skip restoring the vanilla PPHWSP */
1155 engine->pinned_default_state + LRC_STATE_PN * PAGE_SIZE,
1156 engine->context_size - PAGE_SIZE);
1158 execlists_init_reg_state(regs, ce, engine, ce->ring, false);
1161 static void reset_active(struct i915_request *rq,
1162 struct intel_engine_cs *engine)
1164 struct intel_context * const ce = rq->context;
1168 * The executing context has been cancelled. We want to prevent
1169 * further execution along this context and propagate the error on
1170 * to anything depending on its results.
1172 * In __i915_request_submit(), we apply the -EIO and remove the
1173 * requests' payloads for any banned requests. But first, we must
1174 * rewind the context back to the start of the incomplete request so
1175 * that we do not jump back into the middle of the batch.
1177 * We preserve the breadcrumbs and semaphores of the incomplete
1178 * requests so that inter-timeline dependencies (i.e other timelines)
1179 * remain correctly ordered. And we defer to __i915_request_submit()
1180 * so that all asynchronous waits are correctly handled.
1182 ENGINE_TRACE(engine, "{ rq=%llx:%lld }\n",
1183 rq->fence.context, rq->fence.seqno);
1185 /* On resubmission of the active request, payload will be scrubbed */
1186 if (i915_request_completed(rq))
1189 head = active_request(ce->timeline, rq)->head;
1190 head = intel_ring_wrap(ce->ring, head);
1192 /* Scrub the context image to prevent replaying the previous batch */
1193 restore_default_state(ce, engine);
1194 __execlists_update_reg_state(ce, engine, head);
1196 /* We've switched away, so this should be a no-op, but intent matters */
1197 ce->lrc_desc |= CTX_DESC_FORCE_RESTORE;
1200 static inline struct intel_engine_cs *
1201 __execlists_schedule_in(struct i915_request *rq)
1203 struct intel_engine_cs * const engine = rq->engine;
1204 struct intel_context * const ce = rq->context;
1206 intel_context_get(ce);
1208 if (unlikely(intel_context_is_banned(ce)))
1209 reset_active(rq, engine);
1211 if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
1212 execlists_check_context(ce, engine);
1215 /* Use a fixed tag for OA and friends */
1216 ce->lrc_desc |= (u64)ce->tag << 32;
1218 /* We don't need a strict matching tag, just different values */
1219 ce->lrc_desc &= ~GENMASK_ULL(47, 37);
1221 (u64)(++engine->context_tag % NUM_CONTEXT_TAG) <<
1222 GEN11_SW_CTX_ID_SHIFT;
1223 BUILD_BUG_ON(NUM_CONTEXT_TAG > GEN12_MAX_CONTEXT_HW_ID);
1226 __intel_gt_pm_get(engine->gt);
1227 execlists_context_status_change(rq, INTEL_CONTEXT_SCHEDULE_IN);
1228 intel_engine_context_in(engine);
1233 static inline struct i915_request *
1234 execlists_schedule_in(struct i915_request *rq, int idx)
1236 struct intel_context * const ce = rq->context;
1237 struct intel_engine_cs *old;
1239 GEM_BUG_ON(!intel_engine_pm_is_awake(rq->engine));
1240 trace_i915_request_in(rq, idx);
1242 old = READ_ONCE(ce->inflight);
1245 WRITE_ONCE(ce->inflight, __execlists_schedule_in(rq));
1248 } while (!try_cmpxchg(&ce->inflight, &old, ptr_inc(old)));
1250 GEM_BUG_ON(intel_context_inflight(ce) != rq->engine);
1251 return i915_request_get(rq);
1254 static void kick_siblings(struct i915_request *rq, struct intel_context *ce)
1256 struct virtual_engine *ve = container_of(ce, typeof(*ve), context);
1257 struct i915_request *next = READ_ONCE(ve->request);
1259 if (next && next->execution_mask & ~rq->execution_mask)
1260 tasklet_schedule(&ve->base.execlists.tasklet);
1264 __execlists_schedule_out(struct i915_request *rq,
1265 struct intel_engine_cs * const engine)
1267 struct intel_context * const ce = rq->context;
1270 * NB process_csb() is not under the engine->active.lock and hence
1271 * schedule_out can race with schedule_in meaning that we should
1272 * refrain from doing non-trivial work here.
1276 * If we have just completed this context, the engine may now be
1277 * idle and we want to re-enter powersaving.
1279 if (list_is_last(&rq->link, &ce->timeline->requests) &&
1280 i915_request_completed(rq))
1281 intel_engine_add_retire(engine, ce->timeline);
1283 intel_engine_context_out(engine);
1284 execlists_context_status_change(rq, INTEL_CONTEXT_SCHEDULE_OUT);
1285 intel_gt_pm_put_async(engine->gt);
1288 * If this is part of a virtual engine, its next request may
1289 * have been blocked waiting for access to the active context.
1290 * We have to kick all the siblings again in case we need to
1291 * switch (e.g. the next request is not runnable on this
1292 * engine). Hopefully, we will already have submitted the next
1293 * request before the tasklet runs and do not need to rebuild
1294 * each virtual tree and kick everyone again.
1296 if (ce->engine != engine)
1297 kick_siblings(rq, ce);
1299 intel_context_put(ce);
1303 execlists_schedule_out(struct i915_request *rq)
1305 struct intel_context * const ce = rq->context;
1306 struct intel_engine_cs *cur, *old;
1308 trace_i915_request_out(rq);
1310 old = READ_ONCE(ce->inflight);
1312 cur = ptr_unmask_bits(old, 2) ? ptr_dec(old) : NULL;
1313 while (!try_cmpxchg(&ce->inflight, &old, cur));
1315 __execlists_schedule_out(rq, old);
1317 i915_request_put(rq);
1320 static u64 execlists_update_context(struct i915_request *rq)
1322 struct intel_context *ce = rq->context;
1323 u64 desc = ce->lrc_desc;
1327 * WaIdleLiteRestore:bdw,skl
1329 * We should never submit the context with the same RING_TAIL twice
1330 * just in case we submit an empty ring, which confuses the HW.
1332 * We append a couple of NOOPs (gen8_emit_wa_tail) after the end of
1333 * the normal request to be able to always advance the RING_TAIL on
1334 * subsequent resubmissions (for lite restore). Should that fail us,
1335 * and we try and submit the same tail again, force the context
1338 * If we need to return to a preempted context, we need to skip the
1339 * lite-restore and force it to reload the RING_TAIL. Otherwise, the
1340 * HW has a tendency to ignore us rewinding the TAIL to the end of
1341 * an earlier request.
1343 tail = intel_ring_set_tail(rq->ring, rq->tail);
1344 prev = ce->lrc_reg_state[CTX_RING_TAIL];
1345 if (unlikely(intel_ring_direction(rq->ring, tail, prev) <= 0))
1346 desc |= CTX_DESC_FORCE_RESTORE;
1347 ce->lrc_reg_state[CTX_RING_TAIL] = tail;
1348 rq->tail = rq->wa_tail;
1351 * Make sure the context image is complete before we submit it to HW.
1353 * Ostensibly, writes (including the WCB) should be flushed prior to
1354 * an uncached write such as our mmio register access, the empirical
1355 * evidence (esp. on Braswell) suggests that the WC write into memory
1356 * may not be visible to the HW prior to the completion of the UC
1357 * register write and that we may begin execution from the context
1358 * before its image is complete leading to invalid PD chasing.
1362 ce->lrc_desc &= ~CTX_DESC_FORCE_RESTORE;
1366 static inline void write_desc(struct intel_engine_execlists *execlists, u64 desc, u32 port)
1368 if (execlists->ctrl_reg) {
1369 writel(lower_32_bits(desc), execlists->submit_reg + port * 2);
1370 writel(upper_32_bits(desc), execlists->submit_reg + port * 2 + 1);
1372 writel(upper_32_bits(desc), execlists->submit_reg);
1373 writel(lower_32_bits(desc), execlists->submit_reg);
1377 static __maybe_unused void
1378 trace_ports(const struct intel_engine_execlists *execlists,
1380 struct i915_request * const *ports)
1382 const struct intel_engine_cs *engine =
1383 container_of(execlists, typeof(*engine), execlists);
1388 ENGINE_TRACE(engine, "%s { %llx:%lld%s, %llx:%lld }\n", msg,
1389 ports[0]->fence.context,
1390 ports[0]->fence.seqno,
1391 i915_request_completed(ports[0]) ? "!" :
1392 i915_request_started(ports[0]) ? "*" :
1394 ports[1] ? ports[1]->fence.context : 0,
1395 ports[1] ? ports[1]->fence.seqno : 0);
1398 static __maybe_unused bool
1399 assert_pending_valid(const struct intel_engine_execlists *execlists,
1402 struct i915_request * const *port, *rq;
1403 struct intel_context *ce = NULL;
1405 trace_ports(execlists, msg, execlists->pending);
1407 if (!execlists->pending[0]) {
1408 GEM_TRACE_ERR("Nothing pending for promotion!\n");
1412 if (execlists->pending[execlists_num_ports(execlists)]) {
1413 GEM_TRACE_ERR("Excess pending[%d] for promotion!\n",
1414 execlists_num_ports(execlists));
1418 for (port = execlists->pending; (rq = *port); port++) {
1419 unsigned long flags;
1422 GEM_BUG_ON(!kref_read(&rq->fence.refcount));
1423 GEM_BUG_ON(!i915_request_is_active(rq));
1425 if (ce == rq->context) {
1426 GEM_TRACE_ERR("Dup context:%llx in pending[%zd]\n",
1427 ce->timeline->fence_context,
1428 port - execlists->pending);
1433 /* Hold tightly onto the lock to prevent concurrent retires! */
1434 if (!spin_trylock_irqsave(&rq->lock, flags))
1437 if (i915_request_completed(rq))
1440 if (i915_active_is_idle(&ce->active) &&
1441 !intel_context_is_barrier(ce)) {
1442 GEM_TRACE_ERR("Inactive context:%llx in pending[%zd]\n",
1443 ce->timeline->fence_context,
1444 port - execlists->pending);
1449 if (!i915_vma_is_pinned(ce->state)) {
1450 GEM_TRACE_ERR("Unpinned context:%llx in pending[%zd]\n",
1451 ce->timeline->fence_context,
1452 port - execlists->pending);
1457 if (!i915_vma_is_pinned(ce->ring->vma)) {
1458 GEM_TRACE_ERR("Unpinned ring:%llx in pending[%zd]\n",
1459 ce->timeline->fence_context,
1460 port - execlists->pending);
1466 spin_unlock_irqrestore(&rq->lock, flags);
1474 static void execlists_submit_ports(struct intel_engine_cs *engine)
1476 struct intel_engine_execlists *execlists = &engine->execlists;
1479 GEM_BUG_ON(!assert_pending_valid(execlists, "submit"));
1482 * We can skip acquiring intel_runtime_pm_get() here as it was taken
1483 * on our behalf by the request (see i915_gem_mark_busy()) and it will
1484 * not be relinquished until the device is idle (see
1485 * i915_gem_idle_work_handler()). As a precaution, we make sure
1486 * that all ELSP are drained i.e. we have processed the CSB,
1487 * before allowing ourselves to idle and calling intel_runtime_pm_put().
1489 GEM_BUG_ON(!intel_engine_pm_is_awake(engine));
1492 * ELSQ note: the submit queue is not cleared after being submitted
1493 * to the HW so we need to make sure we always clean it up. This is
1494 * currently ensured by the fact that we always write the same number
1495 * of elsq entries, keep this in mind before changing the loop below.
1497 for (n = execlists_num_ports(execlists); n--; ) {
1498 struct i915_request *rq = execlists->pending[n];
1500 write_desc(execlists,
1501 rq ? execlists_update_context(rq) : 0,
1505 /* we need to manually load the submit queue */
1506 if (execlists->ctrl_reg)
1507 writel(EL_CTRL_LOAD, execlists->ctrl_reg);
1510 static bool ctx_single_port_submission(const struct intel_context *ce)
1512 return (IS_ENABLED(CONFIG_DRM_I915_GVT) &&
1513 intel_context_force_single_submission(ce));
1516 static bool can_merge_ctx(const struct intel_context *prev,
1517 const struct intel_context *next)
1522 if (ctx_single_port_submission(prev))
1528 static bool can_merge_rq(const struct i915_request *prev,
1529 const struct i915_request *next)
1531 GEM_BUG_ON(prev == next);
1532 GEM_BUG_ON(!assert_priority_queue(prev, next));
1535 * We do not submit known completed requests. Therefore if the next
1536 * request is already completed, we can pretend to merge it in
1537 * with the previous context (and we will skip updating the ELSP
1538 * and tracking). Thus hopefully keeping the ELSP full with active
1539 * contexts, despite the best efforts of preempt-to-busy to confuse
1542 if (i915_request_completed(next))
1545 if (unlikely((prev->fence.flags ^ next->fence.flags) &
1546 (BIT(I915_FENCE_FLAG_NOPREEMPT) |
1547 BIT(I915_FENCE_FLAG_SENTINEL))))
1550 if (!can_merge_ctx(prev->context, next->context))
1556 static void virtual_update_register_offsets(u32 *regs,
1557 struct intel_engine_cs *engine)
1559 set_offsets(regs, reg_offsets(engine), engine, false);
1562 static bool virtual_matches(const struct virtual_engine *ve,
1563 const struct i915_request *rq,
1564 const struct intel_engine_cs *engine)
1566 const struct intel_engine_cs *inflight;
1568 if (!(rq->execution_mask & engine->mask)) /* We peeked too soon! */
1572 * We track when the HW has completed saving the context image
1573 * (i.e. when we have seen the final CS event switching out of
1574 * the context) and must not overwrite the context image before
1575 * then. This restricts us to only using the active engine
1576 * while the previous virtualized request is inflight (so
1577 * we reuse the register offsets). This is a very small
1578 * hystersis on the greedy seelction algorithm.
1580 inflight = intel_context_inflight(&ve->context);
1581 if (inflight && inflight != engine)
1587 static void virtual_xfer_breadcrumbs(struct virtual_engine *ve,
1588 struct intel_engine_cs *engine)
1590 struct intel_engine_cs *old = ve->siblings[0];
1592 /* All unattached (rq->engine == old) must already be completed */
1594 spin_lock(&old->breadcrumbs.irq_lock);
1595 if (!list_empty(&ve->context.signal_link)) {
1596 list_move_tail(&ve->context.signal_link,
1597 &engine->breadcrumbs.signalers);
1598 intel_engine_signal_breadcrumbs(engine);
1600 spin_unlock(&old->breadcrumbs.irq_lock);
1603 static struct i915_request *
1604 last_active(const struct intel_engine_execlists *execlists)
1606 struct i915_request * const *last = READ_ONCE(execlists->active);
1608 while (*last && i915_request_completed(*last))
1614 #define for_each_waiter(p__, rq__) \
1615 list_for_each_entry_lockless(p__, \
1616 &(rq__)->sched.waiters_list, \
1619 static void defer_request(struct i915_request *rq, struct list_head * const pl)
1624 * We want to move the interrupted request to the back of
1625 * the round-robin list (i.e. its priority level), but
1626 * in doing so, we must then move all requests that were in
1627 * flight and were waiting for the interrupted request to
1628 * be run after it again.
1631 struct i915_dependency *p;
1633 GEM_BUG_ON(i915_request_is_active(rq));
1634 list_move_tail(&rq->sched.link, pl);
1636 for_each_waiter(p, rq) {
1637 struct i915_request *w =
1638 container_of(p->waiter, typeof(*w), sched);
1640 /* Leave semaphores spinning on the other engines */
1641 if (w->engine != rq->engine)
1644 /* No waiter should start before its signaler */
1645 GEM_BUG_ON(i915_request_started(w) &&
1646 !i915_request_completed(rq));
1648 GEM_BUG_ON(i915_request_is_active(w));
1649 if (!i915_request_is_ready(w))
1652 if (rq_prio(w) < rq_prio(rq))
1655 GEM_BUG_ON(rq_prio(w) > rq_prio(rq));
1656 list_move_tail(&w->sched.link, &list);
1659 rq = list_first_entry_or_null(&list, typeof(*rq), sched.link);
1663 static void defer_active(struct intel_engine_cs *engine)
1665 struct i915_request *rq;
1667 rq = __unwind_incomplete_requests(engine);
1671 defer_request(rq, i915_sched_lookup_priolist(engine, rq_prio(rq)));
1675 need_timeslice(struct intel_engine_cs *engine, const struct i915_request *rq)
1679 if (!intel_engine_has_timeslices(engine))
1682 hint = engine->execlists.queue_priority_hint;
1683 if (!list_is_last(&rq->sched.link, &engine->active.requests))
1684 hint = max(hint, rq_prio(list_next_entry(rq, sched.link)));
1686 return hint >= effective_prio(rq);
1690 switch_prio(struct intel_engine_cs *engine, const struct i915_request *rq)
1692 if (list_is_last(&rq->sched.link, &engine->active.requests))
1695 return rq_prio(list_next_entry(rq, sched.link));
1698 static inline unsigned long
1699 timeslice(const struct intel_engine_cs *engine)
1701 return READ_ONCE(engine->props.timeslice_duration_ms);
1704 static unsigned long
1705 active_timeslice(const struct intel_engine_cs *engine)
1707 const struct i915_request *rq = *engine->execlists.active;
1709 if (!rq || i915_request_completed(rq))
1712 if (engine->execlists.switch_priority_hint < effective_prio(rq))
1715 return timeslice(engine);
1718 static void set_timeslice(struct intel_engine_cs *engine)
1720 if (!intel_engine_has_timeslices(engine))
1723 set_timer_ms(&engine->execlists.timer, active_timeslice(engine));
1726 static void start_timeslice(struct intel_engine_cs *engine)
1728 struct intel_engine_execlists *execlists = &engine->execlists;
1730 execlists->switch_priority_hint = execlists->queue_priority_hint;
1732 if (timer_pending(&execlists->timer))
1735 set_timer_ms(&execlists->timer, timeslice(engine));
1738 static void record_preemption(struct intel_engine_execlists *execlists)
1740 (void)I915_SELFTEST_ONLY(execlists->preempt_hang.count++);
1743 static unsigned long active_preempt_timeout(struct intel_engine_cs *engine)
1745 struct i915_request *rq;
1747 rq = last_active(&engine->execlists);
1751 /* Force a fast reset for terminated contexts (ignoring sysfs!) */
1752 if (unlikely(intel_context_is_banned(rq->context)))
1755 return READ_ONCE(engine->props.preempt_timeout_ms);
1758 static void set_preempt_timeout(struct intel_engine_cs *engine)
1760 if (!intel_engine_has_preempt_reset(engine))
1763 set_timer_ms(&engine->execlists.preempt,
1764 active_preempt_timeout(engine));
1767 static inline void clear_ports(struct i915_request **ports, int count)
1769 memset_p((void **)ports, NULL, count);
1772 static void execlists_dequeue(struct intel_engine_cs *engine)
1774 struct intel_engine_execlists * const execlists = &engine->execlists;
1775 struct i915_request **port = execlists->pending;
1776 struct i915_request ** const last_port = port + execlists->port_mask;
1777 struct i915_request *last;
1779 bool submit = false;
1782 * Hardware submission is through 2 ports. Conceptually each port
1783 * has a (RING_START, RING_HEAD, RING_TAIL) tuple. RING_START is
1784 * static for a context, and unique to each, so we only execute
1785 * requests belonging to a single context from each ring. RING_HEAD
1786 * is maintained by the CS in the context image, it marks the place
1787 * where it got up to last time, and through RING_TAIL we tell the CS
1788 * where we want to execute up to this time.
1790 * In this list the requests are in order of execution. Consecutive
1791 * requests from the same context are adjacent in the ringbuffer. We
1792 * can combine these requests into a single RING_TAIL update:
1794 * RING_HEAD...req1...req2
1796 * since to execute req2 the CS must first execute req1.
1798 * Our goal then is to point each port to the end of a consecutive
1799 * sequence of requests as being the most optimal (fewest wake ups
1800 * and context switches) submission.
1803 for (rb = rb_first_cached(&execlists->virtual); rb; ) {
1804 struct virtual_engine *ve =
1805 rb_entry(rb, typeof(*ve), nodes[engine->id].rb);
1806 struct i915_request *rq = READ_ONCE(ve->request);
1808 if (!rq) { /* lazily cleanup after another engine handled rq */
1809 rb_erase_cached(rb, &execlists->virtual);
1811 rb = rb_first_cached(&execlists->virtual);
1815 if (!virtual_matches(ve, rq, engine)) {
1824 * If the queue is higher priority than the last
1825 * request in the currently active context, submit afresh.
1826 * We will resubmit again afterwards in case we need to split
1827 * the active context to interject the preemption request,
1828 * i.e. we will retrigger preemption following the ack in case
1831 last = last_active(execlists);
1833 if (need_preempt(engine, last, rb)) {
1834 ENGINE_TRACE(engine,
1835 "preempting last=%llx:%lld, prio=%d, hint=%d\n",
1836 last->fence.context,
1838 last->sched.attr.priority,
1839 execlists->queue_priority_hint);
1840 record_preemption(execlists);
1843 * Don't let the RING_HEAD advance past the breadcrumb
1844 * as we unwind (and until we resubmit) so that we do
1845 * not accidentally tell it to go backwards.
1847 ring_set_paused(engine, 1);
1850 * Note that we have not stopped the GPU at this point,
1851 * so we are unwinding the incomplete requests as they
1852 * remain inflight and so by the time we do complete
1853 * the preemption, some of the unwound requests may
1856 __unwind_incomplete_requests(engine);
1859 } else if (need_timeslice(engine, last) &&
1860 timer_expired(&engine->execlists.timer)) {
1861 ENGINE_TRACE(engine,
1862 "expired last=%llx:%lld, prio=%d, hint=%d\n",
1863 last->fence.context,
1865 last->sched.attr.priority,
1866 execlists->queue_priority_hint);
1868 ring_set_paused(engine, 1);
1869 defer_active(engine);
1872 * Unlike for preemption, if we rewind and continue
1873 * executing the same context as previously active,
1874 * the order of execution will remain the same and
1875 * the tail will only advance. We do not need to
1876 * force a full context restore, as a lite-restore
1877 * is sufficient to resample the monotonic TAIL.
1879 * If we switch to any other context, similarly we
1880 * will not rewind TAIL of current context, and
1881 * normal save/restore will preserve state and allow
1882 * us to later continue executing the same request.
1887 * Otherwise if we already have a request pending
1888 * for execution after the current one, we can
1889 * just wait until the next CS event before
1890 * queuing more. In either case we will force a
1891 * lite-restore preemption event, but if we wait
1892 * we hopefully coalesce several updates into a single
1895 if (!list_is_last(&last->sched.link,
1896 &engine->active.requests)) {
1898 * Even if ELSP[1] is occupied and not worthy
1899 * of timeslices, our queue might be.
1901 start_timeslice(engine);
1907 while (rb) { /* XXX virtual is always taking precedence */
1908 struct virtual_engine *ve =
1909 rb_entry(rb, typeof(*ve), nodes[engine->id].rb);
1910 struct i915_request *rq;
1912 spin_lock(&ve->base.active.lock);
1915 if (unlikely(!rq)) { /* lost the race to a sibling */
1916 spin_unlock(&ve->base.active.lock);
1917 rb_erase_cached(rb, &execlists->virtual);
1919 rb = rb_first_cached(&execlists->virtual);
1923 GEM_BUG_ON(rq != ve->request);
1924 GEM_BUG_ON(rq->engine != &ve->base);
1925 GEM_BUG_ON(rq->context != &ve->context);
1927 if (rq_prio(rq) >= queue_prio(execlists)) {
1928 if (!virtual_matches(ve, rq, engine)) {
1929 spin_unlock(&ve->base.active.lock);
1934 if (last && !can_merge_rq(last, rq)) {
1935 spin_unlock(&ve->base.active.lock);
1936 start_timeslice(engine);
1937 return; /* leave this for another sibling */
1940 ENGINE_TRACE(engine,
1941 "virtual rq=%llx:%lld%s, new engine? %s\n",
1944 i915_request_completed(rq) ? "!" :
1945 i915_request_started(rq) ? "*" :
1947 yesno(engine != ve->siblings[0]));
1950 ve->base.execlists.queue_priority_hint = INT_MIN;
1951 rb_erase_cached(rb, &execlists->virtual);
1954 GEM_BUG_ON(!(rq->execution_mask & engine->mask));
1955 rq->engine = engine;
1957 if (engine != ve->siblings[0]) {
1958 u32 *regs = ve->context.lrc_reg_state;
1961 GEM_BUG_ON(READ_ONCE(ve->context.inflight));
1963 if (!intel_engine_has_relative_mmio(engine))
1964 virtual_update_register_offsets(regs,
1967 if (!list_empty(&ve->context.signals))
1968 virtual_xfer_breadcrumbs(ve, engine);
1971 * Move the bound engine to the top of the list
1972 * for future execution. We then kick this
1973 * tasklet first before checking others, so that
1974 * we preferentially reuse this set of bound
1977 for (n = 1; n < ve->num_siblings; n++) {
1978 if (ve->siblings[n] == engine) {
1979 swap(ve->siblings[n],
1985 GEM_BUG_ON(ve->siblings[0] != engine);
1988 if (__i915_request_submit(rq)) {
1992 i915_request_put(rq);
1995 * Hmm, we have a bunch of virtual engine requests,
1996 * but the first one was already completed (thanks
1997 * preempt-to-busy!). Keep looking at the veng queue
1998 * until we have no more relevant requests (i.e.
1999 * the normal submit queue has higher priority).
2002 spin_unlock(&ve->base.active.lock);
2003 rb = rb_first_cached(&execlists->virtual);
2008 spin_unlock(&ve->base.active.lock);
2012 while ((rb = rb_first_cached(&execlists->queue))) {
2013 struct i915_priolist *p = to_priolist(rb);
2014 struct i915_request *rq, *rn;
2017 priolist_for_each_request_consume(rq, rn, p, i) {
2021 * Can we combine this request with the current port?
2022 * It has to be the same context/ringbuffer and not
2023 * have any exceptions (e.g. GVT saying never to
2024 * combine contexts).
2026 * If we can combine the requests, we can execute both
2027 * by updating the RING_TAIL to point to the end of the
2028 * second request, and so we never need to tell the
2029 * hardware about the first.
2031 if (last && !can_merge_rq(last, rq)) {
2033 * If we are on the second port and cannot
2034 * combine this request with the last, then we
2037 if (port == last_port)
2041 * We must not populate both ELSP[] with the
2042 * same LRCA, i.e. we must submit 2 different
2043 * contexts if we submit 2 ELSP.
2045 if (last->context == rq->context)
2048 if (i915_request_has_sentinel(last))
2052 * If GVT overrides us we only ever submit
2053 * port[0], leaving port[1] empty. Note that we
2054 * also have to be careful that we don't queue
2055 * the same context (even though a different
2056 * request) to the second port.
2058 if (ctx_single_port_submission(last->context) ||
2059 ctx_single_port_submission(rq->context))
2065 if (__i915_request_submit(rq)) {
2067 *port = execlists_schedule_in(last, port - execlists->pending);
2073 !can_merge_ctx(last->context,
2081 rb_erase_cached(&p->node, &execlists->queue);
2082 i915_priolist_free(p);
2087 * Here be a bit of magic! Or sleight-of-hand, whichever you prefer.
2089 * We choose the priority hint such that if we add a request of greater
2090 * priority than this, we kick the submission tasklet to decide on
2091 * the right order of submitting the requests to hardware. We must
2092 * also be prepared to reorder requests as they are in-flight on the
2093 * HW. We derive the priority hint then as the first "hole" in
2094 * the HW submission ports and if there are no available slots,
2095 * the priority of the lowest executing request, i.e. last.
2097 * When we do receive a higher priority request ready to run from the
2098 * user, see queue_request(), the priority hint is bumped to that
2099 * request triggering preemption on the next dequeue (or subsequent
2100 * interrupt for secondary ports).
2102 execlists->queue_priority_hint = queue_prio(execlists);
2105 *port = execlists_schedule_in(last, port - execlists->pending);
2106 execlists->switch_priority_hint =
2107 switch_prio(engine, *execlists->pending);
2110 * Skip if we ended up with exactly the same set of requests,
2111 * e.g. trying to timeslice a pair of ordered contexts
2113 if (!memcmp(execlists->active, execlists->pending,
2114 (port - execlists->pending + 1) * sizeof(*port))) {
2116 execlists_schedule_out(fetch_and_zero(port));
2117 while (port-- != execlists->pending);
2121 clear_ports(port + 1, last_port - port);
2123 execlists_submit_ports(engine);
2124 set_preempt_timeout(engine);
2127 ring_set_paused(engine, 0);
2132 cancel_port_requests(struct intel_engine_execlists * const execlists)
2134 struct i915_request * const *port;
2136 for (port = execlists->pending; *port; port++)
2137 execlists_schedule_out(*port);
2138 clear_ports(execlists->pending, ARRAY_SIZE(execlists->pending));
2140 /* Mark the end of active before we overwrite *active */
2141 for (port = xchg(&execlists->active, execlists->pending); *port; port++)
2142 execlists_schedule_out(*port);
2143 clear_ports(execlists->inflight, ARRAY_SIZE(execlists->inflight));
2145 WRITE_ONCE(execlists->active, execlists->inflight);
2149 invalidate_csb_entries(const u32 *first, const u32 *last)
2151 clflush((void *)first);
2152 clflush((void *)last);
2156 reset_in_progress(const struct intel_engine_execlists *execlists)
2158 return unlikely(!__tasklet_is_enabled(&execlists->tasklet));
2162 * Starting with Gen12, the status has a new format:
2164 * bit 0: switched to new queue
2166 * bit 2: semaphore wait mode (poll or signal), only valid when
2167 * switch detail is set to "wait on semaphore"
2168 * bits 3-5: engine class
2169 * bits 6-11: engine instance
2170 * bits 12-14: reserved
2171 * bits 15-25: sw context id of the lrc the GT switched to
2172 * bits 26-31: sw counter of the lrc the GT switched to
2173 * bits 32-35: context switch detail
2175 * - 1: wait on sync flip
2176 * - 2: wait on vblank
2177 * - 3: wait on scanline
2178 * - 4: wait on semaphore
2179 * - 5: context preempted (not on SEMAPHORE_WAIT or
2182 * bits 37-43: wait detail (for switch detail 1 to 4)
2183 * bits 44-46: reserved
2184 * bits 47-57: sw context id of the lrc the GT switched away from
2185 * bits 58-63: sw counter of the lrc the GT switched away from
2188 gen12_csb_parse(const struct intel_engine_execlists *execlists, const u32 *csb)
2190 u32 lower_dw = csb[0];
2191 u32 upper_dw = csb[1];
2192 bool ctx_to_valid = GEN12_CSB_CTX_VALID(lower_dw);
2193 bool ctx_away_valid = GEN12_CSB_CTX_VALID(upper_dw);
2194 bool new_queue = lower_dw & GEN12_CTX_STATUS_SWITCHED_TO_NEW_QUEUE;
2197 * The context switch detail is not guaranteed to be 5 when a preemption
2198 * occurs, so we can't just check for that. The check below works for
2199 * all the cases we care about, including preemptions of WAIT
2200 * instructions and lite-restore. Preempt-to-idle via the CTRL register
2201 * would require some extra handling, but we don't support that.
2203 if (!ctx_away_valid || new_queue) {
2204 GEM_BUG_ON(!ctx_to_valid);
2209 * switch detail = 5 is covered by the case above and we do not expect a
2210 * context switch on an unsuccessful wait instruction since we always
2213 GEM_BUG_ON(GEN12_CTX_SWITCH_DETAIL(upper_dw));
2218 gen8_csb_parse(const struct intel_engine_execlists *execlists, const u32 *csb)
2220 return *csb & (GEN8_CTX_STATUS_IDLE_ACTIVE | GEN8_CTX_STATUS_PREEMPTED);
2223 static void process_csb(struct intel_engine_cs *engine)
2225 struct intel_engine_execlists * const execlists = &engine->execlists;
2226 const u32 * const buf = execlists->csb_status;
2227 const u8 num_entries = execlists->csb_size;
2231 * As we modify our execlists state tracking we require exclusive
2232 * access. Either we are inside the tasklet, or the tasklet is disabled
2233 * and we assume that is only inside the reset paths and so serialised.
2235 GEM_BUG_ON(!tasklet_is_locked(&execlists->tasklet) &&
2236 !reset_in_progress(execlists));
2237 GEM_BUG_ON(!intel_engine_in_execlists_submission_mode(engine));
2240 * Note that csb_write, csb_status may be either in HWSP or mmio.
2241 * When reading from the csb_write mmio register, we have to be
2242 * careful to only use the GEN8_CSB_WRITE_PTR portion, which is
2243 * the low 4bits. As it happens we know the next 4bits are always
2244 * zero and so we can simply masked off the low u8 of the register
2245 * and treat it identically to reading from the HWSP (without having
2246 * to use explicit shifting and masking, and probably bifurcating
2247 * the code to handle the legacy mmio read).
2249 head = execlists->csb_head;
2250 tail = READ_ONCE(*execlists->csb_write);
2251 ENGINE_TRACE(engine, "cs-irq head=%d, tail=%d\n", head, tail);
2252 if (unlikely(head == tail))
2256 * Hopefully paired with a wmb() in HW!
2258 * We must complete the read of the write pointer before any reads
2259 * from the CSB, so that we do not see stale values. Without an rmb
2260 * (lfence) the HW may speculatively perform the CSB[] reads *before*
2261 * we perform the READ_ONCE(*csb_write).
2268 if (++head == num_entries)
2272 * We are flying near dragons again.
2274 * We hold a reference to the request in execlist_port[]
2275 * but no more than that. We are operating in softirq
2276 * context and so cannot hold any mutex or sleep. That
2277 * prevents us stopping the requests we are processing
2278 * in port[] from being retired simultaneously (the
2279 * breadcrumb will be complete before we see the
2280 * context-switch). As we only hold the reference to the
2281 * request, any pointer chasing underneath the request
2282 * is subject to a potential use-after-free. Thus we
2283 * store all of the bookkeeping within port[] as
2284 * required, and avoid using unguarded pointers beneath
2285 * request itself. The same applies to the atomic
2289 ENGINE_TRACE(engine, "csb[%d]: status=0x%08x:0x%08x\n",
2290 head, buf[2 * head + 0], buf[2 * head + 1]);
2292 if (INTEL_GEN(engine->i915) >= 12)
2293 promote = gen12_csb_parse(execlists, buf + 2 * head);
2295 promote = gen8_csb_parse(execlists, buf + 2 * head);
2297 struct i915_request * const *old = execlists->active;
2299 /* Point active to the new ELSP; prevent overwriting */
2300 WRITE_ONCE(execlists->active, execlists->pending);
2302 if (!inject_preempt_hang(execlists))
2303 ring_set_paused(engine, 0);
2305 /* cancel old inflight, prepare for switch */
2306 trace_ports(execlists, "preempted", old);
2308 execlists_schedule_out(*old++);
2310 /* switch pending to inflight */
2311 GEM_BUG_ON(!assert_pending_valid(execlists, "promote"));
2312 WRITE_ONCE(execlists->active,
2313 memcpy(execlists->inflight,
2315 execlists_num_ports(execlists) *
2316 sizeof(*execlists->pending)));
2318 WRITE_ONCE(execlists->pending[0], NULL);
2320 GEM_BUG_ON(!*execlists->active);
2322 /* port0 completed, advanced to port1 */
2323 trace_ports(execlists, "completed", execlists->active);
2326 * We rely on the hardware being strongly
2327 * ordered, that the breadcrumb write is
2328 * coherent (visible from the CPU) before the
2329 * user interrupt and CSB is processed.
2331 GEM_BUG_ON(!i915_request_completed(*execlists->active) &&
2332 !reset_in_progress(execlists));
2333 execlists_schedule_out(*execlists->active++);
2335 GEM_BUG_ON(execlists->active - execlists->inflight >
2336 execlists_num_ports(execlists));
2338 } while (head != tail);
2340 execlists->csb_head = head;
2341 set_timeslice(engine);
2344 * Gen11 has proven to fail wrt global observation point between
2345 * entry and tail update, failing on the ordering and thus
2346 * we see an old entry in the context status buffer.
2348 * Forcibly evict out entries for the next gpu csb update,
2349 * to increase the odds that we get a fresh entries with non
2350 * working hardware. The cost for doing so comes out mostly with
2351 * the wash as hardware, working or not, will need to do the
2352 * invalidation before.
2354 invalidate_csb_entries(&buf[0], &buf[num_entries - 1]);
2357 static void __execlists_submission_tasklet(struct intel_engine_cs *const engine)
2359 lockdep_assert_held(&engine->active.lock);
2360 if (!engine->execlists.pending[0]) {
2361 rcu_read_lock(); /* protect peeking at execlists->active */
2362 execlists_dequeue(engine);
2367 static void __execlists_hold(struct i915_request *rq)
2372 struct i915_dependency *p;
2374 if (i915_request_is_active(rq))
2375 __i915_request_unsubmit(rq);
2377 RQ_TRACE(rq, "on hold\n");
2378 clear_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
2379 list_move_tail(&rq->sched.link, &rq->engine->active.hold);
2380 i915_request_set_hold(rq);
2382 list_for_each_entry(p, &rq->sched.waiters_list, wait_link) {
2383 struct i915_request *w =
2384 container_of(p->waiter, typeof(*w), sched);
2386 /* Leave semaphores spinning on the other engines */
2387 if (w->engine != rq->engine)
2390 if (!i915_request_is_ready(w))
2393 if (i915_request_completed(w))
2396 if (i915_request_on_hold(rq))
2399 list_move_tail(&w->sched.link, &list);
2402 rq = list_first_entry_or_null(&list, typeof(*rq), sched.link);
2406 static bool execlists_hold(struct intel_engine_cs *engine,
2407 struct i915_request *rq)
2409 spin_lock_irq(&engine->active.lock);
2411 if (i915_request_completed(rq)) { /* too late! */
2416 if (rq->engine != engine) { /* preempted virtual engine */
2417 struct virtual_engine *ve = to_virtual_engine(rq->engine);
2420 * intel_context_inflight() is only protected by virtue
2421 * of process_csb() being called only by the tasklet (or
2422 * directly from inside reset while the tasklet is suspended).
2423 * Assert that neither of those are allowed to run while we
2424 * poke at the request queues.
2426 GEM_BUG_ON(!reset_in_progress(&engine->execlists));
2429 * An unsubmitted request along a virtual engine will
2430 * remain on the active (this) engine until we are able
2431 * to process the context switch away (and so mark the
2432 * context as no longer in flight). That cannot have happened
2433 * yet, otherwise we would not be hanging!
2435 spin_lock(&ve->base.active.lock);
2436 GEM_BUG_ON(intel_context_inflight(rq->context) != engine);
2437 GEM_BUG_ON(ve->request != rq);
2439 spin_unlock(&ve->base.active.lock);
2440 i915_request_put(rq);
2442 rq->engine = engine;
2446 * Transfer this request onto the hold queue to prevent it
2447 * being resumbitted to HW (and potentially completed) before we have
2448 * released it. Since we may have already submitted following
2449 * requests, we need to remove those as well.
2451 GEM_BUG_ON(i915_request_on_hold(rq));
2452 GEM_BUG_ON(rq->engine != engine);
2453 __execlists_hold(rq);
2456 spin_unlock_irq(&engine->active.lock);
2460 static bool hold_request(const struct i915_request *rq)
2462 struct i915_dependency *p;
2465 * If one of our ancestors is on hold, we must also be on hold,
2466 * otherwise we will bypass it and execute before it.
2468 list_for_each_entry(p, &rq->sched.signalers_list, signal_link) {
2469 const struct i915_request *s =
2470 container_of(p->signaler, typeof(*s), sched);
2472 if (s->engine != rq->engine)
2475 if (i915_request_on_hold(s))
2482 static void __execlists_unhold(struct i915_request *rq)
2487 struct i915_dependency *p;
2489 GEM_BUG_ON(!i915_request_on_hold(rq));
2490 GEM_BUG_ON(!i915_sw_fence_signaled(&rq->submit));
2492 i915_request_clear_hold(rq);
2493 list_move_tail(&rq->sched.link,
2494 i915_sched_lookup_priolist(rq->engine,
2496 set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
2497 RQ_TRACE(rq, "hold release\n");
2499 /* Also release any children on this engine that are ready */
2500 list_for_each_entry(p, &rq->sched.waiters_list, wait_link) {
2501 struct i915_request *w =
2502 container_of(p->waiter, typeof(*w), sched);
2504 if (w->engine != rq->engine)
2507 if (!i915_request_on_hold(rq))
2510 /* Check that no other parents are also on hold */
2511 if (hold_request(rq))
2514 list_move_tail(&w->sched.link, &list);
2517 rq = list_first_entry_or_null(&list, typeof(*rq), sched.link);
2521 static void execlists_unhold(struct intel_engine_cs *engine,
2522 struct i915_request *rq)
2524 spin_lock_irq(&engine->active.lock);
2527 * Move this request back to the priority queue, and all of its
2528 * children and grandchildren that were suspended along with it.
2530 __execlists_unhold(rq);
2532 if (rq_prio(rq) > engine->execlists.queue_priority_hint) {
2533 engine->execlists.queue_priority_hint = rq_prio(rq);
2534 tasklet_hi_schedule(&engine->execlists.tasklet);
2537 spin_unlock_irq(&engine->active.lock);
2540 struct execlists_capture {
2541 struct work_struct work;
2542 struct i915_request *rq;
2543 struct i915_gpu_coredump *error;
2546 static void execlists_capture_work(struct work_struct *work)
2548 struct execlists_capture *cap = container_of(work, typeof(*cap), work);
2549 const gfp_t gfp = GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN;
2550 struct intel_engine_cs *engine = cap->rq->engine;
2551 struct intel_gt_coredump *gt = cap->error->gt;
2552 struct intel_engine_capture_vma *vma;
2554 /* Compress all the objects attached to the request, slow! */
2555 vma = intel_engine_coredump_add_request(gt->engine, cap->rq, gfp);
2557 struct i915_vma_compress *compress =
2558 i915_vma_capture_prepare(gt);
2560 intel_engine_coredump_add_vma(gt->engine, vma, compress);
2561 i915_vma_capture_finish(gt, compress);
2564 gt->simulated = gt->engine->simulated;
2565 cap->error->simulated = gt->simulated;
2567 /* Publish the error state, and announce it to the world */
2568 i915_error_state_store(cap->error);
2569 i915_gpu_coredump_put(cap->error);
2571 /* Return this request and all that depend upon it for signaling */
2572 execlists_unhold(engine, cap->rq);
2573 i915_request_put(cap->rq);
2578 static struct execlists_capture *capture_regs(struct intel_engine_cs *engine)
2580 const gfp_t gfp = GFP_ATOMIC | __GFP_NOWARN;
2581 struct execlists_capture *cap;
2583 cap = kmalloc(sizeof(*cap), gfp);
2587 cap->error = i915_gpu_coredump_alloc(engine->i915, gfp);
2591 cap->error->gt = intel_gt_coredump_alloc(engine->gt, gfp);
2592 if (!cap->error->gt)
2595 cap->error->gt->engine = intel_engine_coredump_alloc(engine, gfp);
2596 if (!cap->error->gt->engine)
2602 kfree(cap->error->gt);
2610 static bool execlists_capture(struct intel_engine_cs *engine)
2612 struct execlists_capture *cap;
2614 if (!IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR))
2618 * We need to _quickly_ capture the engine state before we reset.
2619 * We are inside an atomic section (softirq) here and we are delaying
2620 * the forced preemption event.
2622 cap = capture_regs(engine);
2626 cap->rq = execlists_active(&engine->execlists);
2627 GEM_BUG_ON(!cap->rq);
2630 cap->rq = active_request(cap->rq->context->timeline, cap->rq);
2631 cap->rq = i915_request_get_rcu(cap->rq);
2637 * Remove the request from the execlists queue, and take ownership
2638 * of the request. We pass it to our worker who will _slowly_ compress
2639 * all the pages the _user_ requested for debugging their batch, after
2640 * which we return it to the queue for signaling.
2642 * By removing them from the execlists queue, we also remove the
2643 * requests from being processed by __unwind_incomplete_requests()
2644 * during the intel_engine_reset(), and so they will *not* be replayed
2647 * Note that because we have not yet reset the engine at this point,
2648 * it is possible for the request that we have identified as being
2649 * guilty, did in fact complete and we will then hit an arbitration
2650 * point allowing the outstanding preemption to succeed. The likelihood
2651 * of that is very low (as capturing of the engine registers should be
2652 * fast enough to run inside an irq-off atomic section!), so we will
2653 * simply hold that request accountable for being non-preemptible
2654 * long enough to force the reset.
2656 if (!execlists_hold(engine, cap->rq))
2659 INIT_WORK(&cap->work, execlists_capture_work);
2660 schedule_work(&cap->work);
2664 i915_request_put(cap->rq);
2666 i915_gpu_coredump_put(cap->error);
2671 static noinline void preempt_reset(struct intel_engine_cs *engine)
2673 const unsigned int bit = I915_RESET_ENGINE + engine->id;
2674 unsigned long *lock = &engine->gt->reset.flags;
2676 if (i915_modparams.reset < 3)
2679 if (test_and_set_bit(bit, lock))
2682 /* Mark this tasklet as disabled to avoid waiting for it to complete */
2683 tasklet_disable_nosync(&engine->execlists.tasklet);
2685 ENGINE_TRACE(engine, "preempt timeout %lu+%ums\n",
2686 READ_ONCE(engine->props.preempt_timeout_ms),
2687 jiffies_to_msecs(jiffies - engine->execlists.preempt.expires));
2689 ring_set_paused(engine, 1); /* Freeze the current request in place */
2690 if (execlists_capture(engine))
2691 intel_engine_reset(engine, "preemption time out");
2693 ring_set_paused(engine, 0);
2695 tasklet_enable(&engine->execlists.tasklet);
2696 clear_and_wake_up_bit(bit, lock);
2699 static bool preempt_timeout(const struct intel_engine_cs *const engine)
2701 const struct timer_list *t = &engine->execlists.preempt;
2703 if (!CONFIG_DRM_I915_PREEMPT_TIMEOUT)
2706 if (!timer_expired(t))
2709 return READ_ONCE(engine->execlists.pending[0]);
2713 * Check the unread Context Status Buffers and manage the submission of new
2714 * contexts to the ELSP accordingly.
2716 static void execlists_submission_tasklet(unsigned long data)
2718 struct intel_engine_cs * const engine = (struct intel_engine_cs *)data;
2719 bool timeout = preempt_timeout(engine);
2721 process_csb(engine);
2722 if (!READ_ONCE(engine->execlists.pending[0]) || timeout) {
2723 unsigned long flags;
2725 spin_lock_irqsave(&engine->active.lock, flags);
2726 __execlists_submission_tasklet(engine);
2727 spin_unlock_irqrestore(&engine->active.lock, flags);
2729 /* Recheck after serialising with direct-submission */
2730 if (timeout && preempt_timeout(engine))
2731 preempt_reset(engine);
2735 static void __execlists_kick(struct intel_engine_execlists *execlists)
2737 /* Kick the tasklet for some interrupt coalescing and reset handling */
2738 tasklet_hi_schedule(&execlists->tasklet);
2741 #define execlists_kick(t, member) \
2742 __execlists_kick(container_of(t, struct intel_engine_execlists, member))
2744 static void execlists_timeslice(struct timer_list *timer)
2746 execlists_kick(timer, timer);
2749 static void execlists_preempt(struct timer_list *timer)
2751 execlists_kick(timer, preempt);
2754 static void queue_request(struct intel_engine_cs *engine,
2755 struct i915_request *rq)
2757 GEM_BUG_ON(!list_empty(&rq->sched.link));
2758 list_add_tail(&rq->sched.link,
2759 i915_sched_lookup_priolist(engine, rq_prio(rq)));
2760 set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
2763 static void __submit_queue_imm(struct intel_engine_cs *engine)
2765 struct intel_engine_execlists * const execlists = &engine->execlists;
2767 if (reset_in_progress(execlists))
2768 return; /* defer until we restart the engine following reset */
2770 if (execlists->tasklet.func == execlists_submission_tasklet)
2771 __execlists_submission_tasklet(engine);
2773 tasklet_hi_schedule(&execlists->tasklet);
2776 static void submit_queue(struct intel_engine_cs *engine,
2777 const struct i915_request *rq)
2779 struct intel_engine_execlists *execlists = &engine->execlists;
2781 if (rq_prio(rq) <= execlists->queue_priority_hint)
2784 execlists->queue_priority_hint = rq_prio(rq);
2785 __submit_queue_imm(engine);
2788 static bool ancestor_on_hold(const struct intel_engine_cs *engine,
2789 const struct i915_request *rq)
2791 GEM_BUG_ON(i915_request_on_hold(rq));
2792 return !list_empty(&engine->active.hold) && hold_request(rq);
2795 static void execlists_submit_request(struct i915_request *request)
2797 struct intel_engine_cs *engine = request->engine;
2798 unsigned long flags;
2800 /* Will be called from irq-context when using foreign fences. */
2801 spin_lock_irqsave(&engine->active.lock, flags);
2803 if (unlikely(ancestor_on_hold(engine, request))) {
2804 list_add_tail(&request->sched.link, &engine->active.hold);
2805 i915_request_set_hold(request);
2807 queue_request(engine, request);
2809 GEM_BUG_ON(RB_EMPTY_ROOT(&engine->execlists.queue.rb_root));
2810 GEM_BUG_ON(list_empty(&request->sched.link));
2812 submit_queue(engine, request);
2815 spin_unlock_irqrestore(&engine->active.lock, flags);
2818 static void __execlists_context_fini(struct intel_context *ce)
2820 intel_ring_put(ce->ring);
2821 i915_vma_put(ce->state);
2824 static void execlists_context_destroy(struct kref *kref)
2826 struct intel_context *ce = container_of(kref, typeof(*ce), ref);
2828 GEM_BUG_ON(!i915_active_is_idle(&ce->active));
2829 GEM_BUG_ON(intel_context_is_pinned(ce));
2832 __execlists_context_fini(ce);
2834 intel_context_fini(ce);
2835 intel_context_free(ce);
2839 set_redzone(void *vaddr, const struct intel_engine_cs *engine)
2841 if (!IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
2844 vaddr += engine->context_size;
2846 memset(vaddr, CONTEXT_REDZONE, I915_GTT_PAGE_SIZE);
2850 check_redzone(const void *vaddr, const struct intel_engine_cs *engine)
2852 if (!IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
2855 vaddr += engine->context_size;
2857 if (memchr_inv(vaddr, CONTEXT_REDZONE, I915_GTT_PAGE_SIZE))
2858 dev_err_once(engine->i915->drm.dev,
2859 "%s context redzone overwritten!\n",
2863 static void execlists_context_unpin(struct intel_context *ce)
2865 check_redzone((void *)ce->lrc_reg_state - LRC_STATE_PN * PAGE_SIZE,
2868 i915_gem_object_unpin_map(ce->state->obj);
2872 __execlists_update_reg_state(const struct intel_context *ce,
2873 const struct intel_engine_cs *engine,
2876 struct intel_ring *ring = ce->ring;
2877 u32 *regs = ce->lrc_reg_state;
2879 GEM_BUG_ON(!intel_ring_offset_valid(ring, head));
2880 GEM_BUG_ON(!intel_ring_offset_valid(ring, ring->tail));
2882 regs[CTX_RING_START] = i915_ggtt_offset(ring->vma);
2883 regs[CTX_RING_HEAD] = head;
2884 regs[CTX_RING_TAIL] = ring->tail;
2887 if (engine->class == RENDER_CLASS) {
2888 regs[CTX_R_PWR_CLK_STATE] =
2889 intel_sseu_make_rpcs(engine->i915, &ce->sseu);
2891 i915_oa_init_reg_state(ce, engine);
2896 __execlists_context_pin(struct intel_context *ce,
2897 struct intel_engine_cs *engine)
2901 GEM_BUG_ON(!ce->state);
2902 GEM_BUG_ON(!i915_vma_is_pinned(ce->state));
2904 vaddr = i915_gem_object_pin_map(ce->state->obj,
2905 i915_coherent_map_type(engine->i915) |
2908 return PTR_ERR(vaddr);
2910 ce->lrc_desc = lrc_descriptor(ce, engine) | CTX_DESC_FORCE_RESTORE;
2911 ce->lrc_reg_state = vaddr + LRC_STATE_PN * PAGE_SIZE;
2912 __execlists_update_reg_state(ce, engine, ce->ring->tail);
2917 static int execlists_context_pin(struct intel_context *ce)
2919 return __execlists_context_pin(ce, ce->engine);
2922 static int execlists_context_alloc(struct intel_context *ce)
2924 return __execlists_context_alloc(ce, ce->engine);
2927 static void execlists_context_reset(struct intel_context *ce)
2929 CE_TRACE(ce, "reset\n");
2930 GEM_BUG_ON(!intel_context_is_pinned(ce));
2933 * Because we emit WA_TAIL_DWORDS there may be a disparity
2934 * between our bookkeeping in ce->ring->head and ce->ring->tail and
2935 * that stored in context. As we only write new commands from
2936 * ce->ring->tail onwards, everything before that is junk. If the GPU
2937 * starts reading from its RING_HEAD from the context, it may try to
2938 * execute that junk and die.
2940 * The contexts that are stilled pinned on resume belong to the
2941 * kernel, and are local to each engine. All other contexts will
2942 * have their head/tail sanitized upon pinning before use, so they
2943 * will never see garbage,
2945 * So to avoid that we reset the context images upon resume. For
2946 * simplicity, we just zero everything out.
2948 intel_ring_reset(ce->ring, ce->ring->emit);
2950 /* Scrub away the garbage */
2951 execlists_init_reg_state(ce->lrc_reg_state,
2952 ce, ce->engine, ce->ring, true);
2953 __execlists_update_reg_state(ce, ce->engine, ce->ring->tail);
2955 ce->lrc_desc |= CTX_DESC_FORCE_RESTORE;
2958 static const struct intel_context_ops execlists_context_ops = {
2959 .alloc = execlists_context_alloc,
2961 .pin = execlists_context_pin,
2962 .unpin = execlists_context_unpin,
2964 .enter = intel_context_enter_engine,
2965 .exit = intel_context_exit_engine,
2967 .reset = execlists_context_reset,
2968 .destroy = execlists_context_destroy,
2971 static int gen8_emit_init_breadcrumb(struct i915_request *rq)
2975 GEM_BUG_ON(!i915_request_timeline(rq)->has_initial_breadcrumb);
2977 cs = intel_ring_begin(rq, 6);
2982 * Check if we have been preempted before we even get started.
2984 * After this point i915_request_started() reports true, even if
2985 * we get preempted and so are no longer running.
2987 *cs++ = MI_ARB_CHECK;
2990 *cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
2991 *cs++ = i915_request_timeline(rq)->hwsp_offset;
2993 *cs++ = rq->fence.seqno - 1;
2995 intel_ring_advance(rq, cs);
2997 /* Record the updated position of the request's payload */
2998 rq->infix = intel_ring_offset(rq, cs);
3003 static int execlists_request_alloc(struct i915_request *request)
3007 GEM_BUG_ON(!intel_context_is_pinned(request->context));
3010 * Flush enough space to reduce the likelihood of waiting after
3011 * we start building the request - in which case we will just
3012 * have to repeat work.
3014 request->reserved_space += EXECLISTS_REQUEST_SIZE;
3017 * Note that after this point, we have committed to using
3018 * this request as it is being used to both track the
3019 * state of engine initialisation and liveness of the
3020 * golden renderstate above. Think twice before you try
3021 * to cancel/unwind this request now.
3024 /* Unconditionally invalidate GPU caches and TLBs. */
3025 ret = request->engine->emit_flush(request, EMIT_INVALIDATE);
3029 request->reserved_space -= EXECLISTS_REQUEST_SIZE;
3034 * In this WA we need to set GEN8_L3SQCREG4[21:21] and reset it after
3035 * PIPE_CONTROL instruction. This is required for the flush to happen correctly
3036 * but there is a slight complication as this is applied in WA batch where the
3037 * values are only initialized once so we cannot take register value at the
3038 * beginning and reuse it further; hence we save its value to memory, upload a
3039 * constant value with bit21 set and then we restore it back with the saved value.
3040 * To simplify the WA, a constant value is formed by using the default value
3041 * of this register. This shouldn't be a problem because we are only modifying
3042 * it for a short period and this batch in non-premptible. We can ofcourse
3043 * use additional instructions that read the actual value of the register
3044 * at that time and set our bit of interest but it makes the WA complicated.
3046 * This WA is also required for Gen9 so extracting as a function avoids
3050 gen8_emit_flush_coherentl3_wa(struct intel_engine_cs *engine, u32 *batch)
3052 /* NB no one else is allowed to scribble over scratch + 256! */
3053 *batch++ = MI_STORE_REGISTER_MEM_GEN8 | MI_SRM_LRM_GLOBAL_GTT;
3054 *batch++ = i915_mmio_reg_offset(GEN8_L3SQCREG4);
3055 *batch++ = intel_gt_scratch_offset(engine->gt,
3056 INTEL_GT_SCRATCH_FIELD_COHERENTL3_WA);
3059 *batch++ = MI_LOAD_REGISTER_IMM(1);
3060 *batch++ = i915_mmio_reg_offset(GEN8_L3SQCREG4);
3061 *batch++ = 0x40400000 | GEN8_LQSC_FLUSH_COHERENT_LINES;
3063 batch = gen8_emit_pipe_control(batch,
3064 PIPE_CONTROL_CS_STALL |
3065 PIPE_CONTROL_DC_FLUSH_ENABLE,
3068 *batch++ = MI_LOAD_REGISTER_MEM_GEN8 | MI_SRM_LRM_GLOBAL_GTT;
3069 *batch++ = i915_mmio_reg_offset(GEN8_L3SQCREG4);
3070 *batch++ = intel_gt_scratch_offset(engine->gt,
3071 INTEL_GT_SCRATCH_FIELD_COHERENTL3_WA);
3078 * Typically we only have one indirect_ctx and per_ctx batch buffer which are
3079 * initialized at the beginning and shared across all contexts but this field
3080 * helps us to have multiple batches at different offsets and select them based
3081 * on a criteria. At the moment this batch always start at the beginning of the page
3082 * and at this point we don't have multiple wa_ctx batch buffers.
3084 * The number of WA applied are not known at the beginning; we use this field
3085 * to return the no of DWORDS written.
3087 * It is to be noted that this batch does not contain MI_BATCH_BUFFER_END
3088 * so it adds NOOPs as padding to make it cacheline aligned.
3089 * MI_BATCH_BUFFER_END will be added to perctx batch and both of them together
3090 * makes a complete batch buffer.
3092 static u32 *gen8_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch)
3094 /* WaDisableCtxRestoreArbitration:bdw,chv */
3095 *batch++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;
3097 /* WaFlushCoherentL3CacheLinesAtContextSwitch:bdw */
3098 if (IS_BROADWELL(engine->i915))
3099 batch = gen8_emit_flush_coherentl3_wa(engine, batch);
3101 /* WaClearSlmSpaceAtContextSwitch:bdw,chv */
3102 /* Actual scratch location is at 128 bytes offset */
3103 batch = gen8_emit_pipe_control(batch,
3104 PIPE_CONTROL_FLUSH_L3 |
3105 PIPE_CONTROL_STORE_DATA_INDEX |
3106 PIPE_CONTROL_CS_STALL |
3107 PIPE_CONTROL_QW_WRITE,
3108 LRC_PPHWSP_SCRATCH_ADDR);
3110 *batch++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
3112 /* Pad to end of cacheline */
3113 while ((unsigned long)batch % CACHELINE_BYTES)
3117 * MI_BATCH_BUFFER_END is not required in Indirect ctx BB because
3118 * execution depends on the length specified in terms of cache lines
3119 * in the register CTX_RCS_INDIRECT_CTX
3130 static u32 *emit_lri(u32 *batch, const struct lri *lri, unsigned int count)
3132 GEM_BUG_ON(!count || count > 63);
3134 *batch++ = MI_LOAD_REGISTER_IMM(count);
3136 *batch++ = i915_mmio_reg_offset(lri->reg);
3137 *batch++ = lri->value;
3138 } while (lri++, --count);
3144 static u32 *gen9_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch)
3146 static const struct lri lri[] = {
3147 /* WaDisableGatherAtSetShaderCommonSlice:skl,bxt,kbl,glk */
3149 COMMON_SLICE_CHICKEN2,
3150 __MASKED_FIELD(GEN9_DISABLE_GATHER_AT_SET_SHADER_COMMON_SLICE,
3157 __MASKED_FIELD(FF_SLICE_CHICKEN_CL_PROVOKING_VERTEX_FIX,
3158 FF_SLICE_CHICKEN_CL_PROVOKING_VERTEX_FIX),
3164 __MASKED_FIELD(_3D_CHICKEN_SF_PROVOKING_VERTEX_FIX,
3165 _3D_CHICKEN_SF_PROVOKING_VERTEX_FIX),
3169 *batch++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;
3171 /* WaFlushCoherentL3CacheLinesAtContextSwitch:skl,bxt,glk */
3172 batch = gen8_emit_flush_coherentl3_wa(engine, batch);
3174 /* WaClearSlmSpaceAtContextSwitch:skl,bxt,kbl,glk,cfl */
3175 batch = gen8_emit_pipe_control(batch,
3176 PIPE_CONTROL_FLUSH_L3 |
3177 PIPE_CONTROL_STORE_DATA_INDEX |
3178 PIPE_CONTROL_CS_STALL |
3179 PIPE_CONTROL_QW_WRITE,
3180 LRC_PPHWSP_SCRATCH_ADDR);
3182 batch = emit_lri(batch, lri, ARRAY_SIZE(lri));
3184 /* WaMediaPoolStateCmdInWABB:bxt,glk */
3185 if (HAS_POOLED_EU(engine->i915)) {
3187 * EU pool configuration is setup along with golden context
3188 * during context initialization. This value depends on
3189 * device type (2x6 or 3x6) and needs to be updated based
3190 * on which subslice is disabled especially for 2x6
3191 * devices, however it is safe to load default
3192 * configuration of 3x6 device instead of masking off
3193 * corresponding bits because HW ignores bits of a disabled
3194 * subslice and drops down to appropriate config. Please
3195 * see render_state_setup() in i915_gem_render_state.c for
3196 * possible configurations, to avoid duplication they are
3197 * not shown here again.
3199 *batch++ = GEN9_MEDIA_POOL_STATE;
3200 *batch++ = GEN9_MEDIA_POOL_ENABLE;
3201 *batch++ = 0x00777000;
3207 *batch++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
3209 /* Pad to end of cacheline */
3210 while ((unsigned long)batch % CACHELINE_BYTES)
3217 gen10_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch)
3222 * WaPipeControlBefore3DStateSamplePattern: cnl
3224 * Ensure the engine is idle prior to programming a
3225 * 3DSTATE_SAMPLE_PATTERN during a context restore.
3227 batch = gen8_emit_pipe_control(batch,
3228 PIPE_CONTROL_CS_STALL,
3231 * WaPipeControlBefore3DStateSamplePattern says we need 4 dwords for
3232 * the PIPE_CONTROL followed by 12 dwords of 0x0, so 16 dwords in
3233 * total. However, a PIPE_CONTROL is 6 dwords long, not 4, which is
3234 * confusing. Since gen8_emit_pipe_control() already advances the
3235 * batch by 6 dwords, we advance the other 10 here, completing a
3236 * cacheline. It's not clear if the workaround requires this padding
3237 * before other commands, or if it's just the regular padding we would
3238 * already have for the workaround bb, so leave it here for now.
3240 for (i = 0; i < 10; i++)
3243 /* Pad to end of cacheline */
3244 while ((unsigned long)batch % CACHELINE_BYTES)
3250 #define CTX_WA_BB_OBJ_SIZE (PAGE_SIZE)
3252 static int lrc_setup_wa_ctx(struct intel_engine_cs *engine)
3254 struct drm_i915_gem_object *obj;
3255 struct i915_vma *vma;
3258 obj = i915_gem_object_create_shmem(engine->i915, CTX_WA_BB_OBJ_SIZE);
3260 return PTR_ERR(obj);
3262 vma = i915_vma_instance(obj, &engine->gt->ggtt->vm, NULL);
3268 err = i915_vma_pin(vma, 0, 0, PIN_GLOBAL | PIN_HIGH);
3272 engine->wa_ctx.vma = vma;
3276 i915_gem_object_put(obj);
3280 static void lrc_destroy_wa_ctx(struct intel_engine_cs *engine)
3282 i915_vma_unpin_and_release(&engine->wa_ctx.vma, 0);
3285 typedef u32 *(*wa_bb_func_t)(struct intel_engine_cs *engine, u32 *batch);
3287 static int intel_init_workaround_bb(struct intel_engine_cs *engine)
3289 struct i915_ctx_workarounds *wa_ctx = &engine->wa_ctx;
3290 struct i915_wa_ctx_bb *wa_bb[2] = { &wa_ctx->indirect_ctx,
3292 wa_bb_func_t wa_bb_fn[2];
3294 void *batch, *batch_ptr;
3298 if (engine->class != RENDER_CLASS)
3301 switch (INTEL_GEN(engine->i915)) {
3306 wa_bb_fn[0] = gen10_init_indirectctx_bb;
3310 wa_bb_fn[0] = gen9_init_indirectctx_bb;
3314 wa_bb_fn[0] = gen8_init_indirectctx_bb;
3318 MISSING_CASE(INTEL_GEN(engine->i915));
3322 ret = lrc_setup_wa_ctx(engine);
3324 DRM_DEBUG_DRIVER("Failed to setup context WA page: %d\n", ret);
3328 page = i915_gem_object_get_dirty_page(wa_ctx->vma->obj, 0);
3329 batch = batch_ptr = kmap_atomic(page);
3332 * Emit the two workaround batch buffers, recording the offset from the
3333 * start of the workaround batch buffer object for each and their
3336 for (i = 0; i < ARRAY_SIZE(wa_bb_fn); i++) {
3337 wa_bb[i]->offset = batch_ptr - batch;
3338 if (GEM_DEBUG_WARN_ON(!IS_ALIGNED(wa_bb[i]->offset,
3339 CACHELINE_BYTES))) {
3344 batch_ptr = wa_bb_fn[i](engine, batch_ptr);
3345 wa_bb[i]->size = batch_ptr - (batch + wa_bb[i]->offset);
3348 BUG_ON(batch_ptr - batch > CTX_WA_BB_OBJ_SIZE);
3350 kunmap_atomic(batch);
3352 lrc_destroy_wa_ctx(engine);
3357 static void enable_execlists(struct intel_engine_cs *engine)
3361 assert_forcewakes_active(engine->uncore, FORCEWAKE_ALL);
3363 intel_engine_set_hwsp_writemask(engine, ~0u); /* HWSTAM */
3365 if (INTEL_GEN(engine->i915) >= 11)
3366 mode = _MASKED_BIT_ENABLE(GEN11_GFX_DISABLE_LEGACY_MODE);
3368 mode = _MASKED_BIT_ENABLE(GFX_RUN_LIST_ENABLE);
3369 ENGINE_WRITE_FW(engine, RING_MODE_GEN7, mode);
3371 ENGINE_WRITE_FW(engine, RING_MI_MODE, _MASKED_BIT_DISABLE(STOP_RING));
3373 ENGINE_WRITE_FW(engine,
3375 i915_ggtt_offset(engine->status_page.vma));
3376 ENGINE_POSTING_READ(engine, RING_HWS_PGA);
3378 engine->context_tag = 0;
3381 static bool unexpected_starting_state(struct intel_engine_cs *engine)
3383 bool unexpected = false;
3385 if (ENGINE_READ_FW(engine, RING_MI_MODE) & STOP_RING) {
3386 DRM_DEBUG_DRIVER("STOP_RING still set in RING_MI_MODE\n");
3393 static int execlists_resume(struct intel_engine_cs *engine)
3395 intel_engine_apply_workarounds(engine);
3396 intel_engine_apply_whitelist(engine);
3398 intel_mocs_init_engine(engine);
3400 intel_engine_reset_breadcrumbs(engine);
3402 if (GEM_SHOW_DEBUG() && unexpected_starting_state(engine)) {
3403 struct drm_printer p = drm_debug_printer(__func__);
3405 intel_engine_dump(engine, &p, NULL);
3408 enable_execlists(engine);
3413 static void execlists_reset_prepare(struct intel_engine_cs *engine)
3415 struct intel_engine_execlists * const execlists = &engine->execlists;
3416 unsigned long flags;
3418 ENGINE_TRACE(engine, "depth<-%d\n",
3419 atomic_read(&execlists->tasklet.count));
3422 * Prevent request submission to the hardware until we have
3423 * completed the reset in i915_gem_reset_finish(). If a request
3424 * is completed by one engine, it may then queue a request
3425 * to a second via its execlists->tasklet *just* as we are
3426 * calling engine->resume() and also writing the ELSP.
3427 * Turning off the execlists->tasklet until the reset is over
3428 * prevents the race.
3430 __tasklet_disable_sync_once(&execlists->tasklet);
3431 GEM_BUG_ON(!reset_in_progress(execlists));
3433 /* And flush any current direct submission. */
3434 spin_lock_irqsave(&engine->active.lock, flags);
3435 spin_unlock_irqrestore(&engine->active.lock, flags);
3438 * We stop engines, otherwise we might get failed reset and a
3439 * dead gpu (on elk). Also as modern gpu as kbl can suffer
3440 * from system hang if batchbuffer is progressing when
3441 * the reset is issued, regardless of READY_TO_RESET ack.
3442 * Thus assume it is best to stop engines on all gens
3443 * where we have a gpu reset.
3445 * WaKBLVECSSemaphoreWaitPoll:kbl (on ALL_ENGINES)
3447 * FIXME: Wa for more modern gens needs to be validated
3449 intel_engine_stop_cs(engine);
3452 static void reset_csb_pointers(struct intel_engine_cs *engine)
3454 struct intel_engine_execlists * const execlists = &engine->execlists;
3455 const unsigned int reset_value = execlists->csb_size - 1;
3457 ring_set_paused(engine, 0);
3460 * After a reset, the HW starts writing into CSB entry [0]. We
3461 * therefore have to set our HEAD pointer back one entry so that
3462 * the *first* entry we check is entry 0. To complicate this further,
3463 * as we don't wait for the first interrupt after reset, we have to
3464 * fake the HW write to point back to the last entry so that our
3465 * inline comparison of our cached head position against the last HW
3466 * write works even before the first interrupt.
3468 execlists->csb_head = reset_value;
3469 WRITE_ONCE(*execlists->csb_write, reset_value);
3470 wmb(); /* Make sure this is visible to HW (paranoia?) */
3473 * Sometimes Icelake forgets to reset its pointers on a GPU reset.
3474 * Bludgeon them with a mmio update to be sure.
3476 ENGINE_WRITE(engine, RING_CONTEXT_STATUS_PTR,
3477 reset_value << 8 | reset_value);
3478 ENGINE_POSTING_READ(engine, RING_CONTEXT_STATUS_PTR);
3480 invalidate_csb_entries(&execlists->csb_status[0],
3481 &execlists->csb_status[reset_value]);
3484 static void __reset_stop_ring(u32 *regs, const struct intel_engine_cs *engine)
3488 x = lrc_ring_mi_mode(engine);
3490 regs[x + 1] &= ~STOP_RING;
3491 regs[x + 1] |= STOP_RING << 16;
3495 static void __execlists_reset_reg_state(const struct intel_context *ce,
3496 const struct intel_engine_cs *engine)
3498 u32 *regs = ce->lrc_reg_state;
3500 __reset_stop_ring(regs, engine);
3503 static void __execlists_reset(struct intel_engine_cs *engine, bool stalled)
3505 struct intel_engine_execlists * const execlists = &engine->execlists;
3506 struct intel_context *ce;
3507 struct i915_request *rq;
3510 mb(); /* paranoia: read the CSB pointers from after the reset */
3511 clflush(execlists->csb_write);
3514 process_csb(engine); /* drain preemption events */
3516 /* Following the reset, we need to reload the CSB read/write pointers */
3517 reset_csb_pointers(engine);
3520 * Save the currently executing context, even if we completed
3521 * its request, it was still running at the time of the
3522 * reset and will have been clobbered.
3524 rq = execlists_active(execlists);
3528 /* We still have requests in-flight; the engine should be active */
3529 GEM_BUG_ON(!intel_engine_pm_is_awake(engine));
3532 GEM_BUG_ON(!i915_vma_is_pinned(ce->state));
3534 if (i915_request_completed(rq)) {
3535 /* Idle context; tidy up the ring so we can restart afresh */
3536 head = intel_ring_wrap(ce->ring, rq->tail);
3540 /* Context has requests still in-flight; it should not be idle! */
3541 GEM_BUG_ON(i915_active_is_idle(&ce->active));
3542 rq = active_request(ce->timeline, rq);
3543 head = intel_ring_wrap(ce->ring, rq->head);
3544 GEM_BUG_ON(head == ce->ring->tail);
3547 * If this request hasn't started yet, e.g. it is waiting on a
3548 * semaphore, we need to avoid skipping the request or else we
3549 * break the signaling chain. However, if the context is corrupt
3550 * the request will not restart and we will be stuck with a wedged
3551 * device. It is quite often the case that if we issue a reset
3552 * while the GPU is loading the context image, that the context
3553 * image becomes corrupt.
3555 * Otherwise, if we have not started yet, the request should replay
3556 * perfectly and we do not need to flag the result as being erroneous.
3558 if (!i915_request_started(rq))
3562 * If the request was innocent, we leave the request in the ELSP
3563 * and will try to replay it on restarting. The context image may
3564 * have been corrupted by the reset, in which case we may have
3565 * to service a new GPU hang, but more likely we can continue on
3568 * If the request was guilty, we presume the context is corrupt
3569 * and have to at least restore the RING register in the context
3570 * image back to the expected values to skip over the guilty request.
3572 __i915_request_reset(rq, stalled);
3577 * We want a simple context + ring to execute the breadcrumb update.
3578 * We cannot rely on the context being intact across the GPU hang,
3579 * so clear it and rebuild just what we need for the breadcrumb.
3580 * All pending requests for this context will be zapped, and any
3581 * future request will be after userspace has had the opportunity
3582 * to recreate its own state.
3584 GEM_BUG_ON(!intel_context_is_pinned(ce));
3585 restore_default_state(ce, engine);
3588 ENGINE_TRACE(engine, "replay {head:%04x, tail:%04x}\n",
3589 head, ce->ring->tail);
3590 __execlists_reset_reg_state(ce, engine);
3591 __execlists_update_reg_state(ce, engine, head);
3592 ce->lrc_desc |= CTX_DESC_FORCE_RESTORE; /* paranoid: GPU was reset! */
3595 /* Push back any incomplete requests for replay after the reset. */
3596 cancel_port_requests(execlists);
3597 __unwind_incomplete_requests(engine);
3600 static void execlists_reset_rewind(struct intel_engine_cs *engine, bool stalled)
3602 unsigned long flags;
3604 ENGINE_TRACE(engine, "\n");
3606 spin_lock_irqsave(&engine->active.lock, flags);
3608 __execlists_reset(engine, stalled);
3610 spin_unlock_irqrestore(&engine->active.lock, flags);
3613 static void nop_submission_tasklet(unsigned long data)
3615 /* The driver is wedged; don't process any more events. */
3618 static void execlists_reset_cancel(struct intel_engine_cs *engine)
3620 struct intel_engine_execlists * const execlists = &engine->execlists;
3621 struct i915_request *rq, *rn;
3623 unsigned long flags;
3625 ENGINE_TRACE(engine, "\n");
3628 * Before we call engine->cancel_requests(), we should have exclusive
3629 * access to the submission state. This is arranged for us by the
3630 * caller disabling the interrupt generation, the tasklet and other
3631 * threads that may then access the same state, giving us a free hand
3632 * to reset state. However, we still need to let lockdep be aware that
3633 * we know this state may be accessed in hardirq context, so we
3634 * disable the irq around this manipulation and we want to keep
3635 * the spinlock focused on its duties and not accidentally conflate
3636 * coverage to the submission's irq state. (Similarly, although we
3637 * shouldn't need to disable irq around the manipulation of the
3638 * submission's irq state, we also wish to remind ourselves that
3641 spin_lock_irqsave(&engine->active.lock, flags);
3643 __execlists_reset(engine, true);
3645 /* Mark all executing requests as skipped. */
3646 list_for_each_entry(rq, &engine->active.requests, sched.link)
3649 /* Flush the queued requests to the timeline list (for retiring). */
3650 while ((rb = rb_first_cached(&execlists->queue))) {
3651 struct i915_priolist *p = to_priolist(rb);
3654 priolist_for_each_request_consume(rq, rn, p, i) {
3656 __i915_request_submit(rq);
3659 rb_erase_cached(&p->node, &execlists->queue);
3660 i915_priolist_free(p);
3663 /* On-hold requests will be flushed to timeline upon their release */
3664 list_for_each_entry(rq, &engine->active.hold, sched.link)
3667 /* Cancel all attached virtual engines */
3668 while ((rb = rb_first_cached(&execlists->virtual))) {
3669 struct virtual_engine *ve =
3670 rb_entry(rb, typeof(*ve), nodes[engine->id].rb);
3672 rb_erase_cached(rb, &execlists->virtual);
3675 spin_lock(&ve->base.active.lock);
3676 rq = fetch_and_zero(&ve->request);
3680 rq->engine = engine;
3681 __i915_request_submit(rq);
3682 i915_request_put(rq);
3684 ve->base.execlists.queue_priority_hint = INT_MIN;
3686 spin_unlock(&ve->base.active.lock);
3689 /* Remaining _unready_ requests will be nop'ed when submitted */
3691 execlists->queue_priority_hint = INT_MIN;
3692 execlists->queue = RB_ROOT_CACHED;
3694 GEM_BUG_ON(__tasklet_is_enabled(&execlists->tasklet));
3695 execlists->tasklet.func = nop_submission_tasklet;
3697 spin_unlock_irqrestore(&engine->active.lock, flags);
3700 static void execlists_reset_finish(struct intel_engine_cs *engine)
3702 struct intel_engine_execlists * const execlists = &engine->execlists;
3705 * After a GPU reset, we may have requests to replay. Do so now while
3706 * we still have the forcewake to be sure that the GPU is not allowed
3707 * to sleep before we restart and reload a context.
3709 GEM_BUG_ON(!reset_in_progress(execlists));
3710 if (!RB_EMPTY_ROOT(&execlists->queue.rb_root))
3711 execlists->tasklet.func(execlists->tasklet.data);
3713 if (__tasklet_enable(&execlists->tasklet))
3714 /* And kick in case we missed a new request submission. */
3715 tasklet_hi_schedule(&execlists->tasklet);
3716 ENGINE_TRACE(engine, "depth->%d\n",
3717 atomic_read(&execlists->tasklet.count));
3720 static int gen8_emit_bb_start_noarb(struct i915_request *rq,
3721 u64 offset, u32 len,
3722 const unsigned int flags)
3726 cs = intel_ring_begin(rq, 4);
3731 * WaDisableCtxRestoreArbitration:bdw,chv
3733 * We don't need to perform MI_ARB_ENABLE as often as we do (in
3734 * particular all the gen that do not need the w/a at all!), if we
3735 * took care to make sure that on every switch into this context
3736 * (both ordinary and for preemption) that arbitrartion was enabled
3737 * we would be fine. However, for gen8 there is another w/a that
3738 * requires us to not preempt inside GPGPU execution, so we keep
3739 * arbitration disabled for gen8 batches. Arbitration will be
3740 * re-enabled before we close the request
3741 * (engine->emit_fini_breadcrumb).
3743 *cs++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;
3745 /* FIXME(BDW+): Address space and security selectors. */
3746 *cs++ = MI_BATCH_BUFFER_START_GEN8 |
3747 (flags & I915_DISPATCH_SECURE ? 0 : BIT(8));
3748 *cs++ = lower_32_bits(offset);
3749 *cs++ = upper_32_bits(offset);
3751 intel_ring_advance(rq, cs);
3756 static int gen8_emit_bb_start(struct i915_request *rq,
3757 u64 offset, u32 len,
3758 const unsigned int flags)
3762 cs = intel_ring_begin(rq, 6);
3766 *cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
3768 *cs++ = MI_BATCH_BUFFER_START_GEN8 |
3769 (flags & I915_DISPATCH_SECURE ? 0 : BIT(8));
3770 *cs++ = lower_32_bits(offset);
3771 *cs++ = upper_32_bits(offset);
3773 *cs++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;
3776 intel_ring_advance(rq, cs);
3781 static void gen8_logical_ring_enable_irq(struct intel_engine_cs *engine)
3783 ENGINE_WRITE(engine, RING_IMR,
3784 ~(engine->irq_enable_mask | engine->irq_keep_mask));
3785 ENGINE_POSTING_READ(engine, RING_IMR);
3788 static void gen8_logical_ring_disable_irq(struct intel_engine_cs *engine)
3790 ENGINE_WRITE(engine, RING_IMR, ~engine->irq_keep_mask);
3793 static int gen8_emit_flush(struct i915_request *request, u32 mode)
3797 cs = intel_ring_begin(request, 4);
3801 cmd = MI_FLUSH_DW + 1;
3803 /* We always require a command barrier so that subsequent
3804 * commands, such as breadcrumb interrupts, are strictly ordered
3805 * wrt the contents of the write cache being flushed to memory
3806 * (and thus being coherent from the CPU).
3808 cmd |= MI_FLUSH_DW_STORE_INDEX | MI_FLUSH_DW_OP_STOREDW;
3810 if (mode & EMIT_INVALIDATE) {
3811 cmd |= MI_INVALIDATE_TLB;
3812 if (request->engine->class == VIDEO_DECODE_CLASS)
3813 cmd |= MI_INVALIDATE_BSD;
3817 *cs++ = LRC_PPHWSP_SCRATCH_ADDR;
3818 *cs++ = 0; /* upper addr */
3819 *cs++ = 0; /* value */
3820 intel_ring_advance(request, cs);
3825 static int gen8_emit_flush_render(struct i915_request *request,
3828 bool vf_flush_wa = false, dc_flush_wa = false;
3832 flags |= PIPE_CONTROL_CS_STALL;
3834 if (mode & EMIT_FLUSH) {
3835 flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
3836 flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
3837 flags |= PIPE_CONTROL_DC_FLUSH_ENABLE;
3838 flags |= PIPE_CONTROL_FLUSH_ENABLE;
3841 if (mode & EMIT_INVALIDATE) {
3842 flags |= PIPE_CONTROL_TLB_INVALIDATE;
3843 flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
3844 flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
3845 flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
3846 flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
3847 flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
3848 flags |= PIPE_CONTROL_QW_WRITE;
3849 flags |= PIPE_CONTROL_STORE_DATA_INDEX;
3852 * On GEN9: before VF_CACHE_INVALIDATE we need to emit a NULL
3855 if (IS_GEN(request->i915, 9))
3858 /* WaForGAMHang:kbl */
3859 if (IS_KBL_REVID(request->i915, 0, KBL_REVID_B0))
3871 cs = intel_ring_begin(request, len);
3876 cs = gen8_emit_pipe_control(cs, 0, 0);
3879 cs = gen8_emit_pipe_control(cs, PIPE_CONTROL_DC_FLUSH_ENABLE,
3882 cs = gen8_emit_pipe_control(cs, flags, LRC_PPHWSP_SCRATCH_ADDR);
3885 cs = gen8_emit_pipe_control(cs, PIPE_CONTROL_CS_STALL, 0);
3887 intel_ring_advance(request, cs);
3892 static int gen11_emit_flush_render(struct i915_request *request,
3895 if (mode & EMIT_FLUSH) {
3899 flags |= PIPE_CONTROL_CS_STALL;
3901 flags |= PIPE_CONTROL_TILE_CACHE_FLUSH;
3902 flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
3903 flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
3904 flags |= PIPE_CONTROL_DC_FLUSH_ENABLE;
3905 flags |= PIPE_CONTROL_FLUSH_ENABLE;
3906 flags |= PIPE_CONTROL_QW_WRITE;
3907 flags |= PIPE_CONTROL_STORE_DATA_INDEX;
3909 cs = intel_ring_begin(request, 6);
3913 cs = gen8_emit_pipe_control(cs, flags, LRC_PPHWSP_SCRATCH_ADDR);
3914 intel_ring_advance(request, cs);
3917 if (mode & EMIT_INVALIDATE) {
3921 flags |= PIPE_CONTROL_CS_STALL;
3923 flags |= PIPE_CONTROL_COMMAND_CACHE_INVALIDATE;
3924 flags |= PIPE_CONTROL_TLB_INVALIDATE;
3925 flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
3926 flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
3927 flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
3928 flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
3929 flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
3930 flags |= PIPE_CONTROL_QW_WRITE;
3931 flags |= PIPE_CONTROL_STORE_DATA_INDEX;
3933 cs = intel_ring_begin(request, 6);
3937 cs = gen8_emit_pipe_control(cs, flags, LRC_PPHWSP_SCRATCH_ADDR);
3938 intel_ring_advance(request, cs);
3944 static u32 preparser_disable(bool state)
3946 return MI_ARB_CHECK | 1 << 8 | state;
3949 static int gen12_emit_flush_render(struct i915_request *request,
3952 if (mode & EMIT_FLUSH) {
3956 flags |= PIPE_CONTROL_TILE_CACHE_FLUSH;
3957 flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
3958 flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
3959 /* Wa_1409600907:tgl */
3960 flags |= PIPE_CONTROL_DEPTH_STALL;
3961 flags |= PIPE_CONTROL_DC_FLUSH_ENABLE;
3962 flags |= PIPE_CONTROL_FLUSH_ENABLE;
3963 flags |= PIPE_CONTROL_HDC_PIPELINE_FLUSH;
3965 flags |= PIPE_CONTROL_STORE_DATA_INDEX;
3966 flags |= PIPE_CONTROL_QW_WRITE;
3968 flags |= PIPE_CONTROL_CS_STALL;
3970 cs = intel_ring_begin(request, 6);
3974 cs = gen8_emit_pipe_control(cs, flags, LRC_PPHWSP_SCRATCH_ADDR);
3975 intel_ring_advance(request, cs);
3978 if (mode & EMIT_INVALIDATE) {
3982 flags |= PIPE_CONTROL_COMMAND_CACHE_INVALIDATE;
3983 flags |= PIPE_CONTROL_TLB_INVALIDATE;
3984 flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
3985 flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
3986 flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
3987 flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
3988 flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
3989 flags |= PIPE_CONTROL_L3_RO_CACHE_INVALIDATE;
3991 flags |= PIPE_CONTROL_STORE_DATA_INDEX;
3992 flags |= PIPE_CONTROL_QW_WRITE;
3994 flags |= PIPE_CONTROL_CS_STALL;
3996 cs = intel_ring_begin(request, 8);
4001 * Prevent the pre-parser from skipping past the TLB
4002 * invalidate and loading a stale page for the batch
4003 * buffer / request payload.
4005 *cs++ = preparser_disable(true);
4007 cs = gen8_emit_pipe_control(cs, flags, LRC_PPHWSP_SCRATCH_ADDR);
4009 *cs++ = preparser_disable(false);
4010 intel_ring_advance(request, cs);
4015 if (IS_TGL_REVID(request->i915, TGL_REVID_A0, TGL_REVID_A0)) {
4017 flags |= PIPE_CONTROL_CS_STALL;
4018 flags |= PIPE_CONTROL_HDC_PIPELINE_FLUSH;
4020 flags |= PIPE_CONTROL_STORE_DATA_INDEX;
4021 flags |= PIPE_CONTROL_QW_WRITE;
4023 cs = intel_ring_begin(request, 6);
4027 cs = gen8_emit_pipe_control(cs, flags,
4028 LRC_PPHWSP_SCRATCH_ADDR);
4029 intel_ring_advance(request, cs);
4037 * Reserve space for 2 NOOPs at the end of each request to be
4038 * used as a workaround for not being allowed to do lite
4039 * restore with HEAD==TAIL (WaIdleLiteRestore).
4041 static u32 *gen8_emit_wa_tail(struct i915_request *request, u32 *cs)
4043 /* Ensure there's always at least one preemption point per-request. */
4044 *cs++ = MI_ARB_CHECK;
4046 request->wa_tail = intel_ring_offset(request, cs);
4051 static u32 *emit_preempt_busywait(struct i915_request *request, u32 *cs)
4053 *cs++ = MI_SEMAPHORE_WAIT |
4054 MI_SEMAPHORE_GLOBAL_GTT |
4056 MI_SEMAPHORE_SAD_EQ_SDD;
4058 *cs++ = intel_hws_preempt_address(request->engine);
4064 static __always_inline u32*
4065 gen8_emit_fini_breadcrumb_footer(struct i915_request *request,
4068 *cs++ = MI_USER_INTERRUPT;
4070 *cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
4071 if (intel_engine_has_semaphores(request->engine))
4072 cs = emit_preempt_busywait(request, cs);
4074 request->tail = intel_ring_offset(request, cs);
4075 assert_ring_tail_valid(request->ring, request->tail);
4077 return gen8_emit_wa_tail(request, cs);
4080 static u32 *gen8_emit_fini_breadcrumb(struct i915_request *request, u32 *cs)
4082 cs = gen8_emit_ggtt_write(cs,
4083 request->fence.seqno,
4084 i915_request_active_timeline(request)->hwsp_offset,
4087 return gen8_emit_fini_breadcrumb_footer(request, cs);
4090 static u32 *gen8_emit_fini_breadcrumb_rcs(struct i915_request *request, u32 *cs)
4092 cs = gen8_emit_pipe_control(cs,
4093 PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH |
4094 PIPE_CONTROL_DEPTH_CACHE_FLUSH |
4095 PIPE_CONTROL_DC_FLUSH_ENABLE,
4098 /* XXX flush+write+CS_STALL all in one upsets gem_concurrent_blt:kbl */
4099 cs = gen8_emit_ggtt_write_rcs(cs,
4100 request->fence.seqno,
4101 i915_request_active_timeline(request)->hwsp_offset,
4102 PIPE_CONTROL_FLUSH_ENABLE |
4103 PIPE_CONTROL_CS_STALL);
4105 return gen8_emit_fini_breadcrumb_footer(request, cs);
4109 gen11_emit_fini_breadcrumb_rcs(struct i915_request *request, u32 *cs)
4111 cs = gen8_emit_ggtt_write_rcs(cs,
4112 request->fence.seqno,
4113 i915_request_active_timeline(request)->hwsp_offset,
4114 PIPE_CONTROL_CS_STALL |
4115 PIPE_CONTROL_TILE_CACHE_FLUSH |
4116 PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH |
4117 PIPE_CONTROL_DEPTH_CACHE_FLUSH |
4118 PIPE_CONTROL_DC_FLUSH_ENABLE |
4119 PIPE_CONTROL_FLUSH_ENABLE);
4121 return gen8_emit_fini_breadcrumb_footer(request, cs);
4125 * Note that the CS instruction pre-parser will not stall on the breadcrumb
4126 * flush and will continue pre-fetching the instructions after it before the
4127 * memory sync is completed. On pre-gen12 HW, the pre-parser will stop at
4128 * BB_START/END instructions, so, even though we might pre-fetch the pre-amble
4129 * of the next request before the memory has been flushed, we're guaranteed that
4130 * we won't access the batch itself too early.
4131 * However, on gen12+ the parser can pre-fetch across the BB_START/END commands,
4132 * so, if the current request is modifying an instruction in the next request on
4133 * the same intel_context, we might pre-fetch and then execute the pre-update
4134 * instruction. To avoid this, the users of self-modifying code should either
4135 * disable the parser around the code emitting the memory writes, via a new flag
4136 * added to MI_ARB_CHECK, or emit the writes from a different intel_context. For
4137 * the in-kernel use-cases we've opted to use a separate context, see
4138 * reloc_gpu() as an example.
4139 * All the above applies only to the instructions themselves. Non-inline data
4140 * used by the instructions is not pre-fetched.
4143 static u32 *gen12_emit_preempt_busywait(struct i915_request *request, u32 *cs)
4145 *cs++ = MI_SEMAPHORE_WAIT_TOKEN |
4146 MI_SEMAPHORE_GLOBAL_GTT |
4148 MI_SEMAPHORE_SAD_EQ_SDD;
4150 *cs++ = intel_hws_preempt_address(request->engine);
4158 static __always_inline u32*
4159 gen12_emit_fini_breadcrumb_footer(struct i915_request *request, u32 *cs)
4161 *cs++ = MI_USER_INTERRUPT;
4163 *cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
4164 if (intel_engine_has_semaphores(request->engine))
4165 cs = gen12_emit_preempt_busywait(request, cs);
4167 request->tail = intel_ring_offset(request, cs);
4168 assert_ring_tail_valid(request->ring, request->tail);
4170 return gen8_emit_wa_tail(request, cs);
4173 static u32 *gen12_emit_fini_breadcrumb(struct i915_request *request, u32 *cs)
4175 cs = gen8_emit_ggtt_write(cs,
4176 request->fence.seqno,
4177 i915_request_active_timeline(request)->hwsp_offset,
4180 return gen12_emit_fini_breadcrumb_footer(request, cs);
4184 gen12_emit_fini_breadcrumb_rcs(struct i915_request *request, u32 *cs)
4186 cs = gen8_emit_ggtt_write_rcs(cs,
4187 request->fence.seqno,
4188 i915_request_active_timeline(request)->hwsp_offset,
4189 PIPE_CONTROL_CS_STALL |
4190 PIPE_CONTROL_TILE_CACHE_FLUSH |
4191 PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH |
4192 PIPE_CONTROL_DEPTH_CACHE_FLUSH |
4193 /* Wa_1409600907:tgl */
4194 PIPE_CONTROL_DEPTH_STALL |
4195 PIPE_CONTROL_DC_FLUSH_ENABLE |
4196 PIPE_CONTROL_FLUSH_ENABLE |
4197 PIPE_CONTROL_HDC_PIPELINE_FLUSH);
4199 return gen12_emit_fini_breadcrumb_footer(request, cs);
4202 static void execlists_park(struct intel_engine_cs *engine)
4204 cancel_timer(&engine->execlists.timer);
4205 cancel_timer(&engine->execlists.preempt);
4208 void intel_execlists_set_default_submission(struct intel_engine_cs *engine)
4210 engine->submit_request = execlists_submit_request;
4211 engine->schedule = i915_schedule;
4212 engine->execlists.tasklet.func = execlists_submission_tasklet;
4214 engine->reset.prepare = execlists_reset_prepare;
4215 engine->reset.rewind = execlists_reset_rewind;
4216 engine->reset.cancel = execlists_reset_cancel;
4217 engine->reset.finish = execlists_reset_finish;
4219 engine->park = execlists_park;
4220 engine->unpark = NULL;
4222 engine->flags |= I915_ENGINE_SUPPORTS_STATS;
4223 if (!intel_vgpu_active(engine->i915)) {
4224 engine->flags |= I915_ENGINE_HAS_SEMAPHORES;
4225 if (HAS_LOGICAL_RING_PREEMPTION(engine->i915))
4226 engine->flags |= I915_ENGINE_HAS_PREEMPTION;
4229 if (INTEL_GEN(engine->i915) >= 12)
4230 engine->flags |= I915_ENGINE_HAS_RELATIVE_MMIO;
4232 if (intel_engine_has_preemption(engine))
4233 engine->emit_bb_start = gen8_emit_bb_start;
4235 engine->emit_bb_start = gen8_emit_bb_start_noarb;
4238 static void execlists_shutdown(struct intel_engine_cs *engine)
4240 /* Synchronise with residual timers and any softirq they raise */
4241 del_timer_sync(&engine->execlists.timer);
4242 del_timer_sync(&engine->execlists.preempt);
4243 tasklet_kill(&engine->execlists.tasklet);
4246 static void execlists_release(struct intel_engine_cs *engine)
4248 execlists_shutdown(engine);
4250 intel_engine_cleanup_common(engine);
4251 lrc_destroy_wa_ctx(engine);
4255 logical_ring_default_vfuncs(struct intel_engine_cs *engine)
4257 /* Default vfuncs which can be overriden by each engine. */
4259 engine->resume = execlists_resume;
4261 engine->cops = &execlists_context_ops;
4262 engine->request_alloc = execlists_request_alloc;
4264 engine->emit_flush = gen8_emit_flush;
4265 engine->emit_init_breadcrumb = gen8_emit_init_breadcrumb;
4266 engine->emit_fini_breadcrumb = gen8_emit_fini_breadcrumb;
4267 if (INTEL_GEN(engine->i915) >= 12)
4268 engine->emit_fini_breadcrumb = gen12_emit_fini_breadcrumb;
4270 engine->set_default_submission = intel_execlists_set_default_submission;
4272 if (INTEL_GEN(engine->i915) < 11) {
4273 engine->irq_enable = gen8_logical_ring_enable_irq;
4274 engine->irq_disable = gen8_logical_ring_disable_irq;
4277 * TODO: On Gen11 interrupt masks need to be clear
4278 * to allow C6 entry. Keep interrupts enabled at
4279 * and take the hit of generating extra interrupts
4280 * until a more refined solution exists.
4286 logical_ring_default_irqs(struct intel_engine_cs *engine)
4288 unsigned int shift = 0;
4290 if (INTEL_GEN(engine->i915) < 11) {
4291 const u8 irq_shifts[] = {
4292 [RCS0] = GEN8_RCS_IRQ_SHIFT,
4293 [BCS0] = GEN8_BCS_IRQ_SHIFT,
4294 [VCS0] = GEN8_VCS0_IRQ_SHIFT,
4295 [VCS1] = GEN8_VCS1_IRQ_SHIFT,
4296 [VECS0] = GEN8_VECS_IRQ_SHIFT,
4299 shift = irq_shifts[engine->id];
4302 engine->irq_enable_mask = GT_RENDER_USER_INTERRUPT << shift;
4303 engine->irq_keep_mask = GT_CONTEXT_SWITCH_INTERRUPT << shift;
4306 static void rcs_submission_override(struct intel_engine_cs *engine)
4308 switch (INTEL_GEN(engine->i915)) {
4310 engine->emit_flush = gen12_emit_flush_render;
4311 engine->emit_fini_breadcrumb = gen12_emit_fini_breadcrumb_rcs;
4314 engine->emit_flush = gen11_emit_flush_render;
4315 engine->emit_fini_breadcrumb = gen11_emit_fini_breadcrumb_rcs;
4318 engine->emit_flush = gen8_emit_flush_render;
4319 engine->emit_fini_breadcrumb = gen8_emit_fini_breadcrumb_rcs;
4324 int intel_execlists_submission_setup(struct intel_engine_cs *engine)
4326 struct intel_engine_execlists * const execlists = &engine->execlists;
4327 struct drm_i915_private *i915 = engine->i915;
4328 struct intel_uncore *uncore = engine->uncore;
4329 u32 base = engine->mmio_base;
4331 tasklet_init(&engine->execlists.tasklet,
4332 execlists_submission_tasklet, (unsigned long)engine);
4333 timer_setup(&engine->execlists.timer, execlists_timeslice, 0);
4334 timer_setup(&engine->execlists.preempt, execlists_preempt, 0);
4336 logical_ring_default_vfuncs(engine);
4337 logical_ring_default_irqs(engine);
4339 if (engine->class == RENDER_CLASS)
4340 rcs_submission_override(engine);
4342 if (intel_init_workaround_bb(engine))
4344 * We continue even if we fail to initialize WA batch
4345 * because we only expect rare glitches but nothing
4346 * critical to prevent us from using GPU
4348 DRM_ERROR("WA batch buffer initialization failed\n");
4350 if (HAS_LOGICAL_RING_ELSQ(i915)) {
4351 execlists->submit_reg = uncore->regs +
4352 i915_mmio_reg_offset(RING_EXECLIST_SQ_CONTENTS(base));
4353 execlists->ctrl_reg = uncore->regs +
4354 i915_mmio_reg_offset(RING_EXECLIST_CONTROL(base));
4356 execlists->submit_reg = uncore->regs +
4357 i915_mmio_reg_offset(RING_ELSP(base));
4360 execlists->csb_status =
4361 &engine->status_page.addr[I915_HWS_CSB_BUF0_INDEX];
4363 execlists->csb_write =
4364 &engine->status_page.addr[intel_hws_csb_write_index(i915)];
4366 if (INTEL_GEN(i915) < 11)
4367 execlists->csb_size = GEN8_CSB_ENTRIES;
4369 execlists->csb_size = GEN11_CSB_ENTRIES;
4371 reset_csb_pointers(engine);
4373 /* Finally, take ownership and responsibility for cleanup! */
4374 engine->release = execlists_release;
4379 static u32 intel_lr_indirect_ctx_offset(const struct intel_engine_cs *engine)
4381 u32 indirect_ctx_offset;
4383 switch (INTEL_GEN(engine->i915)) {
4385 MISSING_CASE(INTEL_GEN(engine->i915));
4388 indirect_ctx_offset =
4389 GEN12_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT;
4392 indirect_ctx_offset =
4393 GEN11_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT;
4396 indirect_ctx_offset =
4397 GEN10_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT;
4400 indirect_ctx_offset =
4401 GEN9_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT;
4404 indirect_ctx_offset =
4405 GEN8_CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT;
4409 return indirect_ctx_offset;
4413 static void init_common_reg_state(u32 * const regs,
4414 const struct intel_engine_cs *engine,
4415 const struct intel_ring *ring,
4420 ctl = _MASKED_BIT_ENABLE(CTX_CTRL_INHIBIT_SYN_CTX_SWITCH);
4421 ctl |= _MASKED_BIT_DISABLE(CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT);
4423 ctl |= CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT;
4424 if (INTEL_GEN(engine->i915) < 11)
4425 ctl |= _MASKED_BIT_DISABLE(CTX_CTRL_ENGINE_CTX_SAVE_INHIBIT |
4426 CTX_CTRL_RS_CTX_ENABLE);
4427 regs[CTX_CONTEXT_CONTROL] = ctl;
4429 regs[CTX_RING_CTL] = RING_CTL_SIZE(ring->size) | RING_VALID;
4432 static void init_wa_bb_reg_state(u32 * const regs,
4433 const struct intel_engine_cs *engine,
4436 const struct i915_ctx_workarounds * const wa_ctx = &engine->wa_ctx;
4438 if (wa_ctx->per_ctx.size) {
4439 const u32 ggtt_offset = i915_ggtt_offset(wa_ctx->vma);
4441 regs[pos_bb_per_ctx] =
4442 (ggtt_offset + wa_ctx->per_ctx.offset) | 0x01;
4445 if (wa_ctx->indirect_ctx.size) {
4446 const u32 ggtt_offset = i915_ggtt_offset(wa_ctx->vma);
4448 regs[pos_bb_per_ctx + 2] =
4449 (ggtt_offset + wa_ctx->indirect_ctx.offset) |
4450 (wa_ctx->indirect_ctx.size / CACHELINE_BYTES);
4452 regs[pos_bb_per_ctx + 4] =
4453 intel_lr_indirect_ctx_offset(engine) << 6;
4457 static void init_ppgtt_reg_state(u32 *regs, const struct i915_ppgtt *ppgtt)
4459 if (i915_vm_is_4lvl(&ppgtt->vm)) {
4460 /* 64b PPGTT (48bit canonical)
4461 * PDP0_DESCRIPTOR contains the base address to PML4 and
4462 * other PDP Descriptors are ignored.
4464 ASSIGN_CTX_PML4(ppgtt, regs);
4466 ASSIGN_CTX_PDP(ppgtt, regs, 3);
4467 ASSIGN_CTX_PDP(ppgtt, regs, 2);
4468 ASSIGN_CTX_PDP(ppgtt, regs, 1);
4469 ASSIGN_CTX_PDP(ppgtt, regs, 0);
4473 static struct i915_ppgtt *vm_alias(struct i915_address_space *vm)
4475 if (i915_is_ggtt(vm))
4476 return i915_vm_to_ggtt(vm)->alias;
4478 return i915_vm_to_ppgtt(vm);
4481 static void execlists_init_reg_state(u32 *regs,
4482 const struct intel_context *ce,
4483 const struct intel_engine_cs *engine,
4484 const struct intel_ring *ring,
4488 * A context is actually a big batch buffer with several
4489 * MI_LOAD_REGISTER_IMM commands followed by (reg, value) pairs. The
4490 * values we are setting here are only for the first context restore:
4491 * on a subsequent save, the GPU will recreate this batchbuffer with new
4492 * values (including all the missing MI_LOAD_REGISTER_IMM commands that
4493 * we are not initializing here).
4495 * Must keep consistent with virtual_update_register_offsets().
4497 set_offsets(regs, reg_offsets(engine), engine, inhibit);
4499 init_common_reg_state(regs, engine, ring, inhibit);
4500 init_ppgtt_reg_state(regs, vm_alias(ce->vm));
4502 init_wa_bb_reg_state(regs, engine,
4503 INTEL_GEN(engine->i915) >= 12 ?
4504 GEN12_CTX_BB_PER_CTX_PTR :
4505 CTX_BB_PER_CTX_PTR);
4507 __reset_stop_ring(regs, engine);
4511 populate_lr_context(struct intel_context *ce,
4512 struct drm_i915_gem_object *ctx_obj,
4513 struct intel_engine_cs *engine,
4514 struct intel_ring *ring)
4516 bool inhibit = true;
4520 vaddr = i915_gem_object_pin_map(ctx_obj, I915_MAP_WB);
4521 if (IS_ERR(vaddr)) {
4522 ret = PTR_ERR(vaddr);
4523 DRM_DEBUG_DRIVER("Could not map object pages! (%d)\n", ret);
4527 set_redzone(vaddr, engine);
4529 if (engine->default_state) {
4532 defaults = i915_gem_object_pin_map(engine->default_state,
4534 if (IS_ERR(defaults)) {
4535 ret = PTR_ERR(defaults);
4539 memcpy(vaddr, defaults, engine->context_size);
4540 i915_gem_object_unpin_map(engine->default_state);
4541 __set_bit(CONTEXT_VALID_BIT, &ce->flags);
4545 /* The second page of the context object contains some fields which must
4546 * be set up prior to the first execution. */
4547 execlists_init_reg_state(vaddr + LRC_STATE_PN * PAGE_SIZE,
4548 ce, engine, ring, inhibit);
4552 __i915_gem_object_flush_map(ctx_obj, 0, engine->context_size);
4553 i915_gem_object_unpin_map(ctx_obj);
4557 static int __execlists_context_alloc(struct intel_context *ce,
4558 struct intel_engine_cs *engine)
4560 struct drm_i915_gem_object *ctx_obj;
4561 struct intel_ring *ring;
4562 struct i915_vma *vma;
4566 GEM_BUG_ON(ce->state);
4567 context_size = round_up(engine->context_size, I915_GTT_PAGE_SIZE);
4569 if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
4570 context_size += I915_GTT_PAGE_SIZE; /* for redzone */
4572 ctx_obj = i915_gem_object_create_shmem(engine->i915, context_size);
4573 if (IS_ERR(ctx_obj))
4574 return PTR_ERR(ctx_obj);
4576 vma = i915_vma_instance(ctx_obj, &engine->gt->ggtt->vm, NULL);
4579 goto error_deref_obj;
4582 if (!ce->timeline) {
4583 struct intel_timeline *tl;
4585 tl = intel_timeline_create(engine->gt, NULL);
4588 goto error_deref_obj;
4594 ring = intel_engine_create_ring(engine, (unsigned long)ce->ring);
4596 ret = PTR_ERR(ring);
4597 goto error_deref_obj;
4600 ret = populate_lr_context(ce, ctx_obj, engine, ring);
4602 DRM_DEBUG_DRIVER("Failed to populate LRC: %d\n", ret);
4603 goto error_ring_free;
4612 intel_ring_put(ring);
4614 i915_gem_object_put(ctx_obj);
4618 static struct list_head *virtual_queue(struct virtual_engine *ve)
4620 return &ve->base.execlists.default_priolist.requests[0];
4623 static void virtual_context_destroy(struct kref *kref)
4625 struct virtual_engine *ve =
4626 container_of(kref, typeof(*ve), context.ref);
4629 GEM_BUG_ON(!list_empty(virtual_queue(ve)));
4630 GEM_BUG_ON(ve->request);
4631 GEM_BUG_ON(ve->context.inflight);
4633 for (n = 0; n < ve->num_siblings; n++) {
4634 struct intel_engine_cs *sibling = ve->siblings[n];
4635 struct rb_node *node = &ve->nodes[sibling->id].rb;
4636 unsigned long flags;
4638 if (RB_EMPTY_NODE(node))
4641 spin_lock_irqsave(&sibling->active.lock, flags);
4643 /* Detachment is lazily performed in the execlists tasklet */
4644 if (!RB_EMPTY_NODE(node))
4645 rb_erase_cached(node, &sibling->execlists.virtual);
4647 spin_unlock_irqrestore(&sibling->active.lock, flags);
4649 GEM_BUG_ON(__tasklet_is_scheduled(&ve->base.execlists.tasklet));
4651 if (ve->context.state)
4652 __execlists_context_fini(&ve->context);
4653 intel_context_fini(&ve->context);
4659 static void virtual_engine_initial_hint(struct virtual_engine *ve)
4664 * Pick a random sibling on starting to help spread the load around.
4666 * New contexts are typically created with exactly the same order
4667 * of siblings, and often started in batches. Due to the way we iterate
4668 * the array of sibling when submitting requests, sibling[0] is
4669 * prioritised for dequeuing. If we make sure that sibling[0] is fairly
4670 * randomised across the system, we also help spread the load by the
4671 * first engine we inspect being different each time.
4673 * NB This does not force us to execute on this engine, it will just
4674 * typically be the first we inspect for submission.
4676 swp = prandom_u32_max(ve->num_siblings);
4680 swap(ve->siblings[swp], ve->siblings[0]);
4681 if (!intel_engine_has_relative_mmio(ve->siblings[0]))
4682 virtual_update_register_offsets(ve->context.lrc_reg_state,
4686 static int virtual_context_alloc(struct intel_context *ce)
4688 struct virtual_engine *ve = container_of(ce, typeof(*ve), context);
4690 return __execlists_context_alloc(ce, ve->siblings[0]);
4693 static int virtual_context_pin(struct intel_context *ce)
4695 struct virtual_engine *ve = container_of(ce, typeof(*ve), context);
4698 /* Note: we must use a real engine class for setting up reg state */
4699 err = __execlists_context_pin(ce, ve->siblings[0]);
4703 virtual_engine_initial_hint(ve);
4707 static void virtual_context_enter(struct intel_context *ce)
4709 struct virtual_engine *ve = container_of(ce, typeof(*ve), context);
4712 for (n = 0; n < ve->num_siblings; n++)
4713 intel_engine_pm_get(ve->siblings[n]);
4715 intel_timeline_enter(ce->timeline);
4718 static void virtual_context_exit(struct intel_context *ce)
4720 struct virtual_engine *ve = container_of(ce, typeof(*ve), context);
4723 intel_timeline_exit(ce->timeline);
4725 for (n = 0; n < ve->num_siblings; n++)
4726 intel_engine_pm_put(ve->siblings[n]);
4729 static const struct intel_context_ops virtual_context_ops = {
4730 .alloc = virtual_context_alloc,
4732 .pin = virtual_context_pin,
4733 .unpin = execlists_context_unpin,
4735 .enter = virtual_context_enter,
4736 .exit = virtual_context_exit,
4738 .destroy = virtual_context_destroy,
4741 static intel_engine_mask_t virtual_submission_mask(struct virtual_engine *ve)
4743 struct i915_request *rq;
4744 intel_engine_mask_t mask;
4746 rq = READ_ONCE(ve->request);
4750 /* The rq is ready for submission; rq->execution_mask is now stable. */
4751 mask = rq->execution_mask;
4752 if (unlikely(!mask)) {
4753 /* Invalid selection, submit to a random engine in error */
4754 i915_request_skip(rq, -ENODEV);
4755 mask = ve->siblings[0]->mask;
4758 ENGINE_TRACE(&ve->base, "rq=%llx:%lld, mask=%x, prio=%d\n",
4759 rq->fence.context, rq->fence.seqno,
4760 mask, ve->base.execlists.queue_priority_hint);
4765 static void virtual_submission_tasklet(unsigned long data)
4767 struct virtual_engine * const ve = (struct virtual_engine *)data;
4768 const int prio = ve->base.execlists.queue_priority_hint;
4769 intel_engine_mask_t mask;
4773 mask = virtual_submission_mask(ve);
4775 if (unlikely(!mask))
4778 local_irq_disable();
4779 for (n = 0; READ_ONCE(ve->request) && n < ve->num_siblings; n++) {
4780 struct intel_engine_cs *sibling = ve->siblings[n];
4781 struct ve_node * const node = &ve->nodes[sibling->id];
4782 struct rb_node **parent, *rb;
4785 if (unlikely(!(mask & sibling->mask))) {
4786 if (!RB_EMPTY_NODE(&node->rb)) {
4787 spin_lock(&sibling->active.lock);
4788 rb_erase_cached(&node->rb,
4789 &sibling->execlists.virtual);
4790 RB_CLEAR_NODE(&node->rb);
4791 spin_unlock(&sibling->active.lock);
4796 spin_lock(&sibling->active.lock);
4798 if (!RB_EMPTY_NODE(&node->rb)) {
4800 * Cheat and avoid rebalancing the tree if we can
4801 * reuse this node in situ.
4803 first = rb_first_cached(&sibling->execlists.virtual) ==
4805 if (prio == node->prio || (prio > node->prio && first))
4808 rb_erase_cached(&node->rb, &sibling->execlists.virtual);
4813 parent = &sibling->execlists.virtual.rb_root.rb_node;
4815 struct ve_node *other;
4818 other = rb_entry(rb, typeof(*other), rb);
4819 if (prio > other->prio) {
4820 parent = &rb->rb_left;
4822 parent = &rb->rb_right;
4827 rb_link_node(&node->rb, rb, parent);
4828 rb_insert_color_cached(&node->rb,
4829 &sibling->execlists.virtual,
4833 GEM_BUG_ON(RB_EMPTY_NODE(&node->rb));
4835 if (first && prio > sibling->execlists.queue_priority_hint) {
4836 sibling->execlists.queue_priority_hint = prio;
4837 tasklet_hi_schedule(&sibling->execlists.tasklet);
4840 spin_unlock(&sibling->active.lock);
4845 static void virtual_submit_request(struct i915_request *rq)
4847 struct virtual_engine *ve = to_virtual_engine(rq->engine);
4848 struct i915_request *old;
4849 unsigned long flags;
4851 ENGINE_TRACE(&ve->base, "rq=%llx:%lld\n",
4855 GEM_BUG_ON(ve->base.submit_request != virtual_submit_request);
4857 spin_lock_irqsave(&ve->base.active.lock, flags);
4860 if (old) { /* background completion event from preempt-to-busy */
4861 GEM_BUG_ON(!i915_request_completed(old));
4862 __i915_request_submit(old);
4863 i915_request_put(old);
4866 if (i915_request_completed(rq)) {
4867 __i915_request_submit(rq);
4869 ve->base.execlists.queue_priority_hint = INT_MIN;
4872 ve->base.execlists.queue_priority_hint = rq_prio(rq);
4873 ve->request = i915_request_get(rq);
4875 GEM_BUG_ON(!list_empty(virtual_queue(ve)));
4876 list_move_tail(&rq->sched.link, virtual_queue(ve));
4878 tasklet_schedule(&ve->base.execlists.tasklet);
4881 spin_unlock_irqrestore(&ve->base.active.lock, flags);
4884 static struct ve_bond *
4885 virtual_find_bond(struct virtual_engine *ve,
4886 const struct intel_engine_cs *master)
4890 for (i = 0; i < ve->num_bonds; i++) {
4891 if (ve->bonds[i].master == master)
4892 return &ve->bonds[i];
4899 virtual_bond_execute(struct i915_request *rq, struct dma_fence *signal)
4901 struct virtual_engine *ve = to_virtual_engine(rq->engine);
4902 intel_engine_mask_t allowed, exec;
4903 struct ve_bond *bond;
4905 allowed = ~to_request(signal)->engine->mask;
4907 bond = virtual_find_bond(ve, to_request(signal)->engine);
4909 allowed &= bond->sibling_mask;
4911 /* Restrict the bonded request to run on only the available engines */
4912 exec = READ_ONCE(rq->execution_mask);
4913 while (!try_cmpxchg(&rq->execution_mask, &exec, exec & allowed))
4916 /* Prevent the master from being re-run on the bonded engines */
4917 to_request(signal)->execution_mask &= ~allowed;
4920 struct intel_context *
4921 intel_execlists_create_virtual(struct intel_engine_cs **siblings,
4924 struct virtual_engine *ve;
4929 return ERR_PTR(-EINVAL);
4932 return intel_context_create(siblings[0]);
4934 ve = kzalloc(struct_size(ve, siblings, count), GFP_KERNEL);
4936 return ERR_PTR(-ENOMEM);
4938 ve->base.i915 = siblings[0]->i915;
4939 ve->base.gt = siblings[0]->gt;
4940 ve->base.uncore = siblings[0]->uncore;
4943 ve->base.class = OTHER_CLASS;
4944 ve->base.uabi_class = I915_ENGINE_CLASS_INVALID;
4945 ve->base.instance = I915_ENGINE_CLASS_INVALID_VIRTUAL;
4946 ve->base.uabi_instance = I915_ENGINE_CLASS_INVALID_VIRTUAL;
4949 * The decision on whether to submit a request using semaphores
4950 * depends on the saturated state of the engine. We only compute
4951 * this during HW submission of the request, and we need for this
4952 * state to be globally applied to all requests being submitted
4953 * to this engine. Virtual engines encompass more than one physical
4954 * engine and so we cannot accurately tell in advance if one of those
4955 * engines is already saturated and so cannot afford to use a semaphore
4956 * and be pessimized in priority for doing so -- if we are the only
4957 * context using semaphores after all other clients have stopped, we
4958 * will be starved on the saturated system. Such a global switch for
4959 * semaphores is less than ideal, but alas is the current compromise.
4961 ve->base.saturated = ALL_ENGINES;
4963 snprintf(ve->base.name, sizeof(ve->base.name), "virtual");
4965 intel_engine_init_active(&ve->base, ENGINE_VIRTUAL);
4966 intel_engine_init_breadcrumbs(&ve->base);
4967 intel_engine_init_execlists(&ve->base);
4969 ve->base.cops = &virtual_context_ops;
4970 ve->base.request_alloc = execlists_request_alloc;
4972 ve->base.schedule = i915_schedule;
4973 ve->base.submit_request = virtual_submit_request;
4974 ve->base.bond_execute = virtual_bond_execute;
4976 INIT_LIST_HEAD(virtual_queue(ve));
4977 ve->base.execlists.queue_priority_hint = INT_MIN;
4978 tasklet_init(&ve->base.execlists.tasklet,
4979 virtual_submission_tasklet,
4982 intel_context_init(&ve->context, &ve->base);
4984 for (n = 0; n < count; n++) {
4985 struct intel_engine_cs *sibling = siblings[n];
4987 GEM_BUG_ON(!is_power_of_2(sibling->mask));
4988 if (sibling->mask & ve->base.mask) {
4989 DRM_DEBUG("duplicate %s entry in load balancer\n",
4996 * The virtual engine implementation is tightly coupled to
4997 * the execlists backend -- we push out request directly
4998 * into a tree inside each physical engine. We could support
4999 * layering if we handle cloning of the requests and
5000 * submitting a copy into each backend.
5002 if (sibling->execlists.tasklet.func !=
5003 execlists_submission_tasklet) {
5008 GEM_BUG_ON(RB_EMPTY_NODE(&ve->nodes[sibling->id].rb));
5009 RB_CLEAR_NODE(&ve->nodes[sibling->id].rb);
5011 ve->siblings[ve->num_siblings++] = sibling;
5012 ve->base.mask |= sibling->mask;
5015 * All physical engines must be compatible for their emission
5016 * functions (as we build the instructions during request
5017 * construction and do not alter them before submission
5018 * on the physical engine). We use the engine class as a guide
5019 * here, although that could be refined.
5021 if (ve->base.class != OTHER_CLASS) {
5022 if (ve->base.class != sibling->class) {
5023 DRM_DEBUG("invalid mixing of engine class, sibling %d, already %d\n",
5024 sibling->class, ve->base.class);
5031 ve->base.class = sibling->class;
5032 ve->base.uabi_class = sibling->uabi_class;
5033 snprintf(ve->base.name, sizeof(ve->base.name),
5034 "v%dx%d", ve->base.class, count);
5035 ve->base.context_size = sibling->context_size;
5037 ve->base.emit_bb_start = sibling->emit_bb_start;
5038 ve->base.emit_flush = sibling->emit_flush;
5039 ve->base.emit_init_breadcrumb = sibling->emit_init_breadcrumb;
5040 ve->base.emit_fini_breadcrumb = sibling->emit_fini_breadcrumb;
5041 ve->base.emit_fini_breadcrumb_dw =
5042 sibling->emit_fini_breadcrumb_dw;
5044 ve->base.flags = sibling->flags;
5047 ve->base.flags |= I915_ENGINE_IS_VIRTUAL;
5049 return &ve->context;
5052 intel_context_put(&ve->context);
5053 return ERR_PTR(err);
5056 struct intel_context *
5057 intel_execlists_clone_virtual(struct intel_engine_cs *src)
5059 struct virtual_engine *se = to_virtual_engine(src);
5060 struct intel_context *dst;
5062 dst = intel_execlists_create_virtual(se->siblings,
5067 if (se->num_bonds) {
5068 struct virtual_engine *de = to_virtual_engine(dst->engine);
5070 de->bonds = kmemdup(se->bonds,
5071 sizeof(*se->bonds) * se->num_bonds,
5074 intel_context_put(dst);
5075 return ERR_PTR(-ENOMEM);
5078 de->num_bonds = se->num_bonds;
5084 int intel_virtual_engine_attach_bond(struct intel_engine_cs *engine,
5085 const struct intel_engine_cs *master,
5086 const struct intel_engine_cs *sibling)
5088 struct virtual_engine *ve = to_virtual_engine(engine);
5089 struct ve_bond *bond;
5092 /* Sanity check the sibling is part of the virtual engine */
5093 for (n = 0; n < ve->num_siblings; n++)
5094 if (sibling == ve->siblings[n])
5096 if (n == ve->num_siblings)
5099 bond = virtual_find_bond(ve, master);
5101 bond->sibling_mask |= sibling->mask;
5105 bond = krealloc(ve->bonds,
5106 sizeof(*bond) * (ve->num_bonds + 1),
5111 bond[ve->num_bonds].master = master;
5112 bond[ve->num_bonds].sibling_mask = sibling->mask;
5120 struct intel_engine_cs *
5121 intel_virtual_engine_get_sibling(struct intel_engine_cs *engine,
5122 unsigned int sibling)
5124 struct virtual_engine *ve = to_virtual_engine(engine);
5126 if (sibling >= ve->num_siblings)
5129 return ve->siblings[sibling];
5132 void intel_execlists_show_requests(struct intel_engine_cs *engine,
5133 struct drm_printer *m,
5134 void (*show_request)(struct drm_printer *m,
5135 struct i915_request *rq,
5136 const char *prefix),
5139 const struct intel_engine_execlists *execlists = &engine->execlists;
5140 struct i915_request *rq, *last;
5141 unsigned long flags;
5145 spin_lock_irqsave(&engine->active.lock, flags);
5149 list_for_each_entry(rq, &engine->active.requests, sched.link) {
5150 if (count++ < max - 1)
5151 show_request(m, rq, "\t\tE ");
5158 "\t\t...skipping %d executing requests...\n",
5161 show_request(m, last, "\t\tE ");
5166 if (execlists->queue_priority_hint != INT_MIN)
5167 drm_printf(m, "\t\tQueue priority hint: %d\n",
5168 execlists->queue_priority_hint);
5169 for (rb = rb_first_cached(&execlists->queue); rb; rb = rb_next(rb)) {
5170 struct i915_priolist *p = rb_entry(rb, typeof(*p), node);
5173 priolist_for_each_request(rq, p, i) {
5174 if (count++ < max - 1)
5175 show_request(m, rq, "\t\tQ ");
5183 "\t\t...skipping %d queued requests...\n",
5186 show_request(m, last, "\t\tQ ");
5191 for (rb = rb_first_cached(&execlists->virtual); rb; rb = rb_next(rb)) {
5192 struct virtual_engine *ve =
5193 rb_entry(rb, typeof(*ve), nodes[engine->id].rb);
5194 struct i915_request *rq = READ_ONCE(ve->request);
5197 if (count++ < max - 1)
5198 show_request(m, rq, "\t\tV ");
5206 "\t\t...skipping %d virtual requests...\n",
5209 show_request(m, last, "\t\tV ");
5212 spin_unlock_irqrestore(&engine->active.lock, flags);
5215 void intel_lr_context_reset(struct intel_engine_cs *engine,
5216 struct intel_context *ce,
5220 GEM_BUG_ON(!intel_context_is_pinned(ce));
5223 * We want a simple context + ring to execute the breadcrumb update.
5224 * We cannot rely on the context being intact across the GPU hang,
5225 * so clear it and rebuild just what we need for the breadcrumb.
5226 * All pending requests for this context will be zapped, and any
5227 * future request will be after userspace has had the opportunity
5228 * to recreate its own state.
5231 restore_default_state(ce, engine);
5233 /* Rerun the request; its payload has been neutered (if guilty). */
5234 __execlists_update_reg_state(ce, engine, head);
5238 intel_engine_in_execlists_submission_mode(const struct intel_engine_cs *engine)
5240 return engine->set_default_submission ==
5241 intel_execlists_set_default_submission;
5244 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
5245 #include "selftest_lrc.c"