2 * Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org)
4 * Modifications for ppc64:
5 * Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com>
7 * Copyright 2008 Michael Ellerman, IBM Corporation.
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
15 #include <linux/types.h>
16 #include <linux/jump_label.h>
17 #include <linux/kernel.h>
18 #include <linux/string.h>
19 #include <linux/init.h>
20 #include <linux/sched/mm.h>
21 #include <asm/cputable.h>
22 #include <asm/code-patching.h>
24 #include <asm/sections.h>
25 #include <asm/setup.h>
26 #include <asm/firmware.h>
37 static unsigned int *calc_addr(struct fixup_entry *fcur, long offset)
40 * We store the offset to the code as a negative offset from
41 * the start of the alt_entry, to support the VDSO. This
42 * routine converts that back into an actual address.
44 return (unsigned int *)((unsigned long)fcur + offset);
47 static int patch_alt_instruction(unsigned int *src, unsigned int *dest,
48 unsigned int *alt_start, unsigned int *alt_end)
54 if (instr_is_relative_branch(*src)) {
55 unsigned int *target = (unsigned int *)branch_target(src);
57 /* Branch within the section doesn't need translating */
58 if (target < alt_start || target >= alt_end) {
59 instr = translate_branch(dest, src);
65 raw_patch_instruction(dest, instr);
70 static int patch_feature_section(unsigned long value, struct fixup_entry *fcur)
72 unsigned int *start, *end, *alt_start, *alt_end, *src, *dest;
74 start = calc_addr(fcur, fcur->start_off);
75 end = calc_addr(fcur, fcur->end_off);
76 alt_start = calc_addr(fcur, fcur->alt_start_off);
77 alt_end = calc_addr(fcur, fcur->alt_end_off);
79 if ((alt_end - alt_start) > (end - start))
82 if ((value & fcur->mask) == fcur->value)
88 for (; src < alt_end; src++, dest++) {
89 if (patch_alt_instruction(src, dest, alt_start, alt_end))
93 for (; dest < end; dest++)
94 raw_patch_instruction(dest, PPC_INST_NOP);
99 void do_feature_fixups(unsigned long value, void *fixup_start, void *fixup_end)
101 struct fixup_entry *fcur, *fend;
106 for (; fcur < fend; fcur++) {
107 if (patch_feature_section(value, fcur)) {
109 printk("Unable to patch feature section at %p - %p" \
111 calc_addr(fcur, fcur->start_off),
112 calc_addr(fcur, fcur->end_off),
113 calc_addr(fcur, fcur->alt_start_off),
114 calc_addr(fcur, fcur->alt_end_off));
119 #ifdef CONFIG_PPC_BOOK3S_64
120 void do_rfi_flush_fixups(enum l1d_flush_type types)
122 unsigned int instrs[3], *dest;
126 start = PTRRELOC(&__start___rfi_flush_fixup),
127 end = PTRRELOC(&__stop___rfi_flush_fixup);
129 instrs[0] = 0x60000000; /* nop */
130 instrs[1] = 0x60000000; /* nop */
131 instrs[2] = 0x60000000; /* nop */
133 if (types & L1D_FLUSH_FALLBACK)
134 /* b .+16 to fallback flush */
135 instrs[0] = 0x48000010;
138 if (types & L1D_FLUSH_ORI) {
139 instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
140 instrs[i++] = 0x63de0000; /* ori 30,30,0 L1d flush*/
143 if (types & L1D_FLUSH_MTTRIG)
144 instrs[i++] = 0x7c12dba6; /* mtspr TRIG2,r0 (SPR #882) */
146 for (i = 0; start < end; start++, i++) {
147 dest = (void *)start + *start;
149 pr_devel("patching dest %lx\n", (unsigned long)dest);
151 patch_instruction(dest, instrs[0]);
152 patch_instruction(dest + 1, instrs[1]);
153 patch_instruction(dest + 2, instrs[2]);
156 printk(KERN_DEBUG "rfi-flush: patched %d locations (%s flush)\n", i,
157 (types == L1D_FLUSH_NONE) ? "no" :
158 (types == L1D_FLUSH_FALLBACK) ? "fallback displacement" :
159 (types & L1D_FLUSH_ORI) ? (types & L1D_FLUSH_MTTRIG)
162 (types & L1D_FLUSH_MTTRIG) ? "mttrig type"
165 #endif /* CONFIG_PPC_BOOK3S_64 */
167 void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end)
172 if (!(value & CPU_FTR_LWSYNC))
178 for (; start < end; start++) {
179 dest = (void *)start + *start;
180 raw_patch_instruction(dest, PPC_INST_LWSYNC);
184 static void do_final_fixups(void)
186 #if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE)
188 unsigned long length;
190 if (PHYSICAL_START == 0)
193 src = (int *)(KERNELBASE + PHYSICAL_START);
194 dest = (int *)KERNELBASE;
195 length = (__end_interrupts - _stext) / sizeof(int);
198 raw_patch_instruction(dest, *src);
205 static unsigned long __initdata saved_cpu_features;
206 static unsigned int __initdata saved_mmu_features;
208 static unsigned long __initdata saved_firmware_features;
211 void __init apply_feature_fixups(void)
213 struct cpu_spec *spec = PTRRELOC(*PTRRELOC(&cur_cpu_spec));
215 *PTRRELOC(&saved_cpu_features) = spec->cpu_features;
216 *PTRRELOC(&saved_mmu_features) = spec->mmu_features;
219 * Apply the CPU-specific and firmware specific fixups to kernel text
220 * (nop out sections not relevant to this CPU or this firmware).
222 do_feature_fixups(spec->cpu_features,
223 PTRRELOC(&__start___ftr_fixup),
224 PTRRELOC(&__stop___ftr_fixup));
226 do_feature_fixups(spec->mmu_features,
227 PTRRELOC(&__start___mmu_ftr_fixup),
228 PTRRELOC(&__stop___mmu_ftr_fixup));
230 do_lwsync_fixups(spec->cpu_features,
231 PTRRELOC(&__start___lwsync_fixup),
232 PTRRELOC(&__stop___lwsync_fixup));
235 saved_firmware_features = powerpc_firmware_features;
236 do_feature_fixups(powerpc_firmware_features,
237 &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
242 void __init setup_feature_keys(void)
245 * Initialise jump label. This causes all the cpu/mmu_has_feature()
246 * checks to take on their correct polarity based on the current set of
250 cpu_feature_keys_init();
251 mmu_feature_keys_init();
254 static int __init check_features(void)
256 WARN(saved_cpu_features != cur_cpu_spec->cpu_features,
257 "CPU features changed after feature patching!\n");
258 WARN(saved_mmu_features != cur_cpu_spec->mmu_features,
259 "MMU features changed after feature patching!\n");
261 WARN(saved_firmware_features != powerpc_firmware_features,
262 "Firmware features changed after feature patching!\n");
267 late_initcall(check_features);
269 #ifdef CONFIG_FTR_FIXUP_SELFTEST
272 if (!(x)) printk("feature-fixups: test failed at line %d\n", __LINE__);
274 /* This must be after the text it fixes up, vmlinux.lds.S enforces that atm */
275 static struct fixup_entry fixup;
277 static long calc_offset(struct fixup_entry *entry, unsigned int *p)
279 return (unsigned long)p - (unsigned long)entry;
282 static void test_basic_patching(void)
284 extern unsigned int ftr_fixup_test1[];
285 extern unsigned int end_ftr_fixup_test1[];
286 extern unsigned int ftr_fixup_test1_orig[];
287 extern unsigned int ftr_fixup_test1_expected[];
288 int size = end_ftr_fixup_test1 - ftr_fixup_test1;
290 fixup.value = fixup.mask = 8;
291 fixup.start_off = calc_offset(&fixup, ftr_fixup_test1 + 1);
292 fixup.end_off = calc_offset(&fixup, ftr_fixup_test1 + 2);
293 fixup.alt_start_off = fixup.alt_end_off = 0;
296 check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
298 /* Check we don't patch if the value matches */
299 patch_feature_section(8, &fixup);
300 check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
302 /* Check we do patch if the value doesn't match */
303 patch_feature_section(0, &fixup);
304 check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0);
306 /* Check we do patch if the mask doesn't match */
307 memcpy(ftr_fixup_test1, ftr_fixup_test1_orig, size);
308 check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
309 patch_feature_section(~8, &fixup);
310 check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0);
313 static void test_alternative_patching(void)
315 extern unsigned int ftr_fixup_test2[];
316 extern unsigned int end_ftr_fixup_test2[];
317 extern unsigned int ftr_fixup_test2_orig[];
318 extern unsigned int ftr_fixup_test2_alt[];
319 extern unsigned int ftr_fixup_test2_expected[];
320 int size = end_ftr_fixup_test2 - ftr_fixup_test2;
322 fixup.value = fixup.mask = 0xF;
323 fixup.start_off = calc_offset(&fixup, ftr_fixup_test2 + 1);
324 fixup.end_off = calc_offset(&fixup, ftr_fixup_test2 + 2);
325 fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test2_alt);
326 fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test2_alt + 1);
329 check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
331 /* Check we don't patch if the value matches */
332 patch_feature_section(0xF, &fixup);
333 check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
335 /* Check we do patch if the value doesn't match */
336 patch_feature_section(0, &fixup);
337 check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0);
339 /* Check we do patch if the mask doesn't match */
340 memcpy(ftr_fixup_test2, ftr_fixup_test2_orig, size);
341 check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
342 patch_feature_section(~0xF, &fixup);
343 check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0);
346 static void test_alternative_case_too_big(void)
348 extern unsigned int ftr_fixup_test3[];
349 extern unsigned int end_ftr_fixup_test3[];
350 extern unsigned int ftr_fixup_test3_orig[];
351 extern unsigned int ftr_fixup_test3_alt[];
352 int size = end_ftr_fixup_test3 - ftr_fixup_test3;
354 fixup.value = fixup.mask = 0xC;
355 fixup.start_off = calc_offset(&fixup, ftr_fixup_test3 + 1);
356 fixup.end_off = calc_offset(&fixup, ftr_fixup_test3 + 2);
357 fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test3_alt);
358 fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test3_alt + 2);
361 check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
363 /* Expect nothing to be patched, and the error returned to us */
364 check(patch_feature_section(0xF, &fixup) == 1);
365 check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
366 check(patch_feature_section(0, &fixup) == 1);
367 check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
368 check(patch_feature_section(~0xF, &fixup) == 1);
369 check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
372 static void test_alternative_case_too_small(void)
374 extern unsigned int ftr_fixup_test4[];
375 extern unsigned int end_ftr_fixup_test4[];
376 extern unsigned int ftr_fixup_test4_orig[];
377 extern unsigned int ftr_fixup_test4_alt[];
378 extern unsigned int ftr_fixup_test4_expected[];
379 int size = end_ftr_fixup_test4 - ftr_fixup_test4;
382 /* Check a high-bit flag */
383 flag = 1UL << ((sizeof(unsigned long) - 1) * 8);
384 fixup.value = fixup.mask = flag;
385 fixup.start_off = calc_offset(&fixup, ftr_fixup_test4 + 1);
386 fixup.end_off = calc_offset(&fixup, ftr_fixup_test4 + 5);
387 fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test4_alt);
388 fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test4_alt + 2);
391 check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
393 /* Check we don't patch if the value matches */
394 patch_feature_section(flag, &fixup);
395 check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
397 /* Check we do patch if the value doesn't match */
398 patch_feature_section(0, &fixup);
399 check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0);
401 /* Check we do patch if the mask doesn't match */
402 memcpy(ftr_fixup_test4, ftr_fixup_test4_orig, size);
403 check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
404 patch_feature_section(~flag, &fixup);
405 check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0);
408 static void test_alternative_case_with_branch(void)
410 extern unsigned int ftr_fixup_test5[];
411 extern unsigned int end_ftr_fixup_test5[];
412 extern unsigned int ftr_fixup_test5_expected[];
413 int size = end_ftr_fixup_test5 - ftr_fixup_test5;
415 check(memcmp(ftr_fixup_test5, ftr_fixup_test5_expected, size) == 0);
418 static void test_alternative_case_with_external_branch(void)
420 extern unsigned int ftr_fixup_test6[];
421 extern unsigned int end_ftr_fixup_test6[];
422 extern unsigned int ftr_fixup_test6_expected[];
423 int size = end_ftr_fixup_test6 - ftr_fixup_test6;
425 check(memcmp(ftr_fixup_test6, ftr_fixup_test6_expected, size) == 0);
428 static void test_cpu_macros(void)
430 extern u8 ftr_fixup_test_FTR_macros[];
431 extern u8 ftr_fixup_test_FTR_macros_expected[];
432 unsigned long size = ftr_fixup_test_FTR_macros_expected -
433 ftr_fixup_test_FTR_macros;
435 /* The fixups have already been done for us during boot */
436 check(memcmp(ftr_fixup_test_FTR_macros,
437 ftr_fixup_test_FTR_macros_expected, size) == 0);
440 static void test_fw_macros(void)
443 extern u8 ftr_fixup_test_FW_FTR_macros[];
444 extern u8 ftr_fixup_test_FW_FTR_macros_expected[];
445 unsigned long size = ftr_fixup_test_FW_FTR_macros_expected -
446 ftr_fixup_test_FW_FTR_macros;
448 /* The fixups have already been done for us during boot */
449 check(memcmp(ftr_fixup_test_FW_FTR_macros,
450 ftr_fixup_test_FW_FTR_macros_expected, size) == 0);
454 static void test_lwsync_macros(void)
456 extern u8 lwsync_fixup_test[];
457 extern u8 end_lwsync_fixup_test[];
458 extern u8 lwsync_fixup_test_expected_LWSYNC[];
459 extern u8 lwsync_fixup_test_expected_SYNC[];
460 unsigned long size = end_lwsync_fixup_test -
463 /* The fixups have already been done for us during boot */
464 if (cur_cpu_spec->cpu_features & CPU_FTR_LWSYNC) {
465 check(memcmp(lwsync_fixup_test,
466 lwsync_fixup_test_expected_LWSYNC, size) == 0);
468 check(memcmp(lwsync_fixup_test,
469 lwsync_fixup_test_expected_SYNC, size) == 0);
473 static int __init test_feature_fixups(void)
475 printk(KERN_DEBUG "Running feature fixup self-tests ...\n");
477 test_basic_patching();
478 test_alternative_patching();
479 test_alternative_case_too_big();
480 test_alternative_case_too_small();
481 test_alternative_case_with_branch();
482 test_alternative_case_with_external_branch();
485 test_lwsync_macros();
489 late_initcall(test_feature_fixups);
491 #endif /* CONFIG_FTR_FIXUP_SELFTEST */