2 * Driver for the Atmel Extensible DMA Controller (aka XDMAC on AT91 systems)
4 * Copyright (C) 2014 Atmel Corporation
6 * Author: Ludovic Desroches <ludovic.desroches@atmel.com>
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 as published by
10 * the Free Software Foundation.
12 * This program is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
17 * You should have received a copy of the GNU General Public License along with
18 * this program. If not, see <http://www.gnu.org/licenses/>.
21 #include <asm/barrier.h>
22 #include <dt-bindings/dma/at91.h>
23 #include <linux/clk.h>
24 #include <linux/dmaengine.h>
25 #include <linux/dmapool.h>
26 #include <linux/interrupt.h>
27 #include <linux/irq.h>
28 #include <linux/kernel.h>
29 #include <linux/list.h>
30 #include <linux/module.h>
31 #include <linux/of_dma.h>
32 #include <linux/of_platform.h>
33 #include <linux/platform_device.h>
36 #include "dmaengine.h"
38 /* Global registers */
39 #define AT_XDMAC_GTYPE 0x00 /* Global Type Register */
40 #define AT_XDMAC_NB_CH(i) (((i) & 0x1F) + 1) /* Number of Channels Minus One */
41 #define AT_XDMAC_FIFO_SZ(i) (((i) >> 5) & 0x7FF) /* Number of Bytes */
42 #define AT_XDMAC_NB_REQ(i) ((((i) >> 16) & 0x3F) + 1) /* Number of Peripheral Requests Minus One */
43 #define AT_XDMAC_GCFG 0x04 /* Global Configuration Register */
44 #define AT_XDMAC_GWAC 0x08 /* Global Weighted Arbiter Configuration Register */
45 #define AT_XDMAC_GIE 0x0C /* Global Interrupt Enable Register */
46 #define AT_XDMAC_GID 0x10 /* Global Interrupt Disable Register */
47 #define AT_XDMAC_GIM 0x14 /* Global Interrupt Mask Register */
48 #define AT_XDMAC_GIS 0x18 /* Global Interrupt Status Register */
49 #define AT_XDMAC_GE 0x1C /* Global Channel Enable Register */
50 #define AT_XDMAC_GD 0x20 /* Global Channel Disable Register */
51 #define AT_XDMAC_GS 0x24 /* Global Channel Status Register */
52 #define AT_XDMAC_GRS 0x28 /* Global Channel Read Suspend Register */
53 #define AT_XDMAC_GWS 0x2C /* Global Write Suspend Register */
54 #define AT_XDMAC_GRWS 0x30 /* Global Channel Read Write Suspend Register */
55 #define AT_XDMAC_GRWR 0x34 /* Global Channel Read Write Resume Register */
56 #define AT_XDMAC_GSWR 0x38 /* Global Channel Software Request Register */
57 #define AT_XDMAC_GSWS 0x3C /* Global channel Software Request Status Register */
58 #define AT_XDMAC_GSWF 0x40 /* Global Channel Software Flush Request Register */
59 #define AT_XDMAC_VERSION 0xFFC /* XDMAC Version Register */
61 /* Channel relative registers offsets */
62 #define AT_XDMAC_CIE 0x00 /* Channel Interrupt Enable Register */
63 #define AT_XDMAC_CIE_BIE BIT(0) /* End of Block Interrupt Enable Bit */
64 #define AT_XDMAC_CIE_LIE BIT(1) /* End of Linked List Interrupt Enable Bit */
65 #define AT_XDMAC_CIE_DIE BIT(2) /* End of Disable Interrupt Enable Bit */
66 #define AT_XDMAC_CIE_FIE BIT(3) /* End of Flush Interrupt Enable Bit */
67 #define AT_XDMAC_CIE_RBEIE BIT(4) /* Read Bus Error Interrupt Enable Bit */
68 #define AT_XDMAC_CIE_WBEIE BIT(5) /* Write Bus Error Interrupt Enable Bit */
69 #define AT_XDMAC_CIE_ROIE BIT(6) /* Request Overflow Interrupt Enable Bit */
70 #define AT_XDMAC_CID 0x04 /* Channel Interrupt Disable Register */
71 #define AT_XDMAC_CID_BID BIT(0) /* End of Block Interrupt Disable Bit */
72 #define AT_XDMAC_CID_LID BIT(1) /* End of Linked List Interrupt Disable Bit */
73 #define AT_XDMAC_CID_DID BIT(2) /* End of Disable Interrupt Disable Bit */
74 #define AT_XDMAC_CID_FID BIT(3) /* End of Flush Interrupt Disable Bit */
75 #define AT_XDMAC_CID_RBEID BIT(4) /* Read Bus Error Interrupt Disable Bit */
76 #define AT_XDMAC_CID_WBEID BIT(5) /* Write Bus Error Interrupt Disable Bit */
77 #define AT_XDMAC_CID_ROID BIT(6) /* Request Overflow Interrupt Disable Bit */
78 #define AT_XDMAC_CIM 0x08 /* Channel Interrupt Mask Register */
79 #define AT_XDMAC_CIM_BIM BIT(0) /* End of Block Interrupt Mask Bit */
80 #define AT_XDMAC_CIM_LIM BIT(1) /* End of Linked List Interrupt Mask Bit */
81 #define AT_XDMAC_CIM_DIM BIT(2) /* End of Disable Interrupt Mask Bit */
82 #define AT_XDMAC_CIM_FIM BIT(3) /* End of Flush Interrupt Mask Bit */
83 #define AT_XDMAC_CIM_RBEIM BIT(4) /* Read Bus Error Interrupt Mask Bit */
84 #define AT_XDMAC_CIM_WBEIM BIT(5) /* Write Bus Error Interrupt Mask Bit */
85 #define AT_XDMAC_CIM_ROIM BIT(6) /* Request Overflow Interrupt Mask Bit */
86 #define AT_XDMAC_CIS 0x0C /* Channel Interrupt Status Register */
87 #define AT_XDMAC_CIS_BIS BIT(0) /* End of Block Interrupt Status Bit */
88 #define AT_XDMAC_CIS_LIS BIT(1) /* End of Linked List Interrupt Status Bit */
89 #define AT_XDMAC_CIS_DIS BIT(2) /* End of Disable Interrupt Status Bit */
90 #define AT_XDMAC_CIS_FIS BIT(3) /* End of Flush Interrupt Status Bit */
91 #define AT_XDMAC_CIS_RBEIS BIT(4) /* Read Bus Error Interrupt Status Bit */
92 #define AT_XDMAC_CIS_WBEIS BIT(5) /* Write Bus Error Interrupt Status Bit */
93 #define AT_XDMAC_CIS_ROIS BIT(6) /* Request Overflow Interrupt Status Bit */
94 #define AT_XDMAC_CSA 0x10 /* Channel Source Address Register */
95 #define AT_XDMAC_CDA 0x14 /* Channel Destination Address Register */
96 #define AT_XDMAC_CNDA 0x18 /* Channel Next Descriptor Address Register */
97 #define AT_XDMAC_CNDA_NDAIF(i) ((i) & 0x1) /* Channel x Next Descriptor Interface */
98 #define AT_XDMAC_CNDA_NDA(i) ((i) & 0xfffffffc) /* Channel x Next Descriptor Address */
99 #define AT_XDMAC_CNDC 0x1C /* Channel Next Descriptor Control Register */
100 #define AT_XDMAC_CNDC_NDE (0x1 << 0) /* Channel x Next Descriptor Enable */
101 #define AT_XDMAC_CNDC_NDSUP (0x1 << 1) /* Channel x Next Descriptor Source Update */
102 #define AT_XDMAC_CNDC_NDDUP (0x1 << 2) /* Channel x Next Descriptor Destination Update */
103 #define AT_XDMAC_CNDC_NDVIEW_NDV0 (0x0 << 3) /* Channel x Next Descriptor View 0 */
104 #define AT_XDMAC_CNDC_NDVIEW_NDV1 (0x1 << 3) /* Channel x Next Descriptor View 1 */
105 #define AT_XDMAC_CNDC_NDVIEW_NDV2 (0x2 << 3) /* Channel x Next Descriptor View 2 */
106 #define AT_XDMAC_CNDC_NDVIEW_NDV3 (0x3 << 3) /* Channel x Next Descriptor View 3 */
107 #define AT_XDMAC_CUBC 0x20 /* Channel Microblock Control Register */
108 #define AT_XDMAC_CBC 0x24 /* Channel Block Control Register */
109 #define AT_XDMAC_CC 0x28 /* Channel Configuration Register */
110 #define AT_XDMAC_CC_TYPE (0x1 << 0) /* Channel Transfer Type */
111 #define AT_XDMAC_CC_TYPE_MEM_TRAN (0x0 << 0) /* Memory to Memory Transfer */
112 #define AT_XDMAC_CC_TYPE_PER_TRAN (0x1 << 0) /* Peripheral to Memory or Memory to Peripheral Transfer */
113 #define AT_XDMAC_CC_MBSIZE_MASK (0x3 << 1)
114 #define AT_XDMAC_CC_MBSIZE_SINGLE (0x0 << 1)
115 #define AT_XDMAC_CC_MBSIZE_FOUR (0x1 << 1)
116 #define AT_XDMAC_CC_MBSIZE_EIGHT (0x2 << 1)
117 #define AT_XDMAC_CC_MBSIZE_SIXTEEN (0x3 << 1)
118 #define AT_XDMAC_CC_DSYNC (0x1 << 4) /* Channel Synchronization */
119 #define AT_XDMAC_CC_DSYNC_PER2MEM (0x0 << 4)
120 #define AT_XDMAC_CC_DSYNC_MEM2PER (0x1 << 4)
121 #define AT_XDMAC_CC_PROT (0x1 << 5) /* Channel Protection */
122 #define AT_XDMAC_CC_PROT_SEC (0x0 << 5)
123 #define AT_XDMAC_CC_PROT_UNSEC (0x1 << 5)
124 #define AT_XDMAC_CC_SWREQ (0x1 << 6) /* Channel Software Request Trigger */
125 #define AT_XDMAC_CC_SWREQ_HWR_CONNECTED (0x0 << 6)
126 #define AT_XDMAC_CC_SWREQ_SWR_CONNECTED (0x1 << 6)
127 #define AT_XDMAC_CC_MEMSET (0x1 << 7) /* Channel Fill Block of memory */
128 #define AT_XDMAC_CC_MEMSET_NORMAL_MODE (0x0 << 7)
129 #define AT_XDMAC_CC_MEMSET_HW_MODE (0x1 << 7)
130 #define AT_XDMAC_CC_CSIZE(i) ((0x7 & (i)) << 8) /* Channel Chunk Size */
131 #define AT_XDMAC_CC_DWIDTH_OFFSET 11
132 #define AT_XDMAC_CC_DWIDTH_MASK (0x3 << AT_XDMAC_CC_DWIDTH_OFFSET)
133 #define AT_XDMAC_CC_DWIDTH(i) ((0x3 & (i)) << AT_XDMAC_CC_DWIDTH_OFFSET) /* Channel Data Width */
134 #define AT_XDMAC_CC_DWIDTH_BYTE 0x0
135 #define AT_XDMAC_CC_DWIDTH_HALFWORD 0x1
136 #define AT_XDMAC_CC_DWIDTH_WORD 0x2
137 #define AT_XDMAC_CC_DWIDTH_DWORD 0x3
138 #define AT_XDMAC_CC_SIF(i) ((0x1 & (i)) << 13) /* Channel Source Interface Identifier */
139 #define AT_XDMAC_CC_DIF(i) ((0x1 & (i)) << 14) /* Channel Destination Interface Identifier */
140 #define AT_XDMAC_CC_SAM_MASK (0x3 << 16) /* Channel Source Addressing Mode */
141 #define AT_XDMAC_CC_SAM_FIXED_AM (0x0 << 16)
142 #define AT_XDMAC_CC_SAM_INCREMENTED_AM (0x1 << 16)
143 #define AT_XDMAC_CC_SAM_UBS_AM (0x2 << 16)
144 #define AT_XDMAC_CC_SAM_UBS_DS_AM (0x3 << 16)
145 #define AT_XDMAC_CC_DAM_MASK (0x3 << 18) /* Channel Source Addressing Mode */
146 #define AT_XDMAC_CC_DAM_FIXED_AM (0x0 << 18)
147 #define AT_XDMAC_CC_DAM_INCREMENTED_AM (0x1 << 18)
148 #define AT_XDMAC_CC_DAM_UBS_AM (0x2 << 18)
149 #define AT_XDMAC_CC_DAM_UBS_DS_AM (0x3 << 18)
150 #define AT_XDMAC_CC_INITD (0x1 << 21) /* Channel Initialization Terminated (read only) */
151 #define AT_XDMAC_CC_INITD_TERMINATED (0x0 << 21)
152 #define AT_XDMAC_CC_INITD_IN_PROGRESS (0x1 << 21)
153 #define AT_XDMAC_CC_RDIP (0x1 << 22) /* Read in Progress (read only) */
154 #define AT_XDMAC_CC_RDIP_DONE (0x0 << 22)
155 #define AT_XDMAC_CC_RDIP_IN_PROGRESS (0x1 << 22)
156 #define AT_XDMAC_CC_WRIP (0x1 << 23) /* Write in Progress (read only) */
157 #define AT_XDMAC_CC_WRIP_DONE (0x0 << 23)
158 #define AT_XDMAC_CC_WRIP_IN_PROGRESS (0x1 << 23)
159 #define AT_XDMAC_CC_PERID(i) (0x7f & (i) << 24) /* Channel Peripheral Identifier */
160 #define AT_XDMAC_CDS_MSP 0x2C /* Channel Data Stride Memory Set Pattern */
161 #define AT_XDMAC_CSUS 0x30 /* Channel Source Microblock Stride */
162 #define AT_XDMAC_CDUS 0x34 /* Channel Destination Microblock Stride */
164 #define AT_XDMAC_CHAN_REG_BASE 0x50 /* Channel registers base address */
166 /* Microblock control members */
167 #define AT_XDMAC_MBR_UBC_UBLEN_MAX 0xFFFFFFUL /* Maximum Microblock Length */
168 #define AT_XDMAC_MBR_UBC_NDE (0x1 << 24) /* Next Descriptor Enable */
169 #define AT_XDMAC_MBR_UBC_NSEN (0x1 << 25) /* Next Descriptor Source Update */
170 #define AT_XDMAC_MBR_UBC_NDEN (0x1 << 26) /* Next Descriptor Destination Update */
171 #define AT_XDMAC_MBR_UBC_NDV0 (0x0 << 27) /* Next Descriptor View 0 */
172 #define AT_XDMAC_MBR_UBC_NDV1 (0x1 << 27) /* Next Descriptor View 1 */
173 #define AT_XDMAC_MBR_UBC_NDV2 (0x2 << 27) /* Next Descriptor View 2 */
174 #define AT_XDMAC_MBR_UBC_NDV3 (0x3 << 27) /* Next Descriptor View 3 */
176 #define AT_XDMAC_MAX_CHAN 0x20
177 #define AT_XDMAC_MAX_CSIZE 16 /* 16 data */
178 #define AT_XDMAC_MAX_DWIDTH 8 /* 64 bits */
179 #define AT_XDMAC_RESIDUE_MAX_RETRIES 5
181 #define AT_XDMAC_DMA_BUSWIDTHS\
182 (BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) |\
183 BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |\
184 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |\
185 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |\
186 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES))
189 AT_XDMAC_CHAN_IS_CYCLIC = 0,
190 AT_XDMAC_CHAN_IS_PAUSED,
193 /* ----- Channels ----- */
194 struct at_xdmac_chan {
195 struct dma_chan chan;
196 void __iomem *ch_regs;
197 u32 mask; /* Channel Mask */
198 u32 cfg; /* Channel Configuration Register */
199 u8 perid; /* Peripheral ID */
200 u8 perif; /* Peripheral Interface */
201 u8 memif; /* Memory Interface */
207 unsigned long status;
208 struct tasklet_struct tasklet;
209 struct dma_slave_config sconfig;
213 struct list_head xfers_list;
214 struct list_head free_descs_list;
218 /* ----- Controller ----- */
220 struct dma_device dma;
225 struct dma_pool *at_xdmac_desc_pool;
226 struct at_xdmac_chan chan[0];
230 /* ----- Descriptors ----- */
232 /* Linked List Descriptor */
233 struct at_xdmac_lld {
234 dma_addr_t mbr_nda; /* Next Descriptor Member */
235 u32 mbr_ubc; /* Microblock Control Member */
236 dma_addr_t mbr_sa; /* Source Address Member */
237 dma_addr_t mbr_da; /* Destination Address Member */
238 u32 mbr_cfg; /* Configuration Register */
239 u32 mbr_bc; /* Block Control Register */
240 u32 mbr_ds; /* Data Stride Register */
241 u32 mbr_sus; /* Source Microblock Stride Register */
242 u32 mbr_dus; /* Destination Microblock Stride Register */
245 /* 64-bit alignment needed to update CNDA and CUBC registers in an atomic way. */
246 struct at_xdmac_desc {
247 struct at_xdmac_lld lld;
248 enum dma_transfer_direction direction;
249 struct dma_async_tx_descriptor tx_dma_desc;
250 struct list_head desc_node;
251 /* Following members are only used by the first descriptor */
253 unsigned int xfer_size;
254 struct list_head descs_list;
255 struct list_head xfer_node;
256 } __aligned(sizeof(u64));
258 static inline void __iomem *at_xdmac_chan_reg_base(struct at_xdmac *atxdmac, unsigned int chan_nb)
260 return atxdmac->regs + (AT_XDMAC_CHAN_REG_BASE + chan_nb * 0x40);
263 #define at_xdmac_read(atxdmac, reg) readl_relaxed((atxdmac)->regs + (reg))
264 #define at_xdmac_write(atxdmac, reg, value) \
265 writel_relaxed((value), (atxdmac)->regs + (reg))
267 #define at_xdmac_chan_read(atchan, reg) readl_relaxed((atchan)->ch_regs + (reg))
268 #define at_xdmac_chan_write(atchan, reg, value) writel_relaxed((value), (atchan)->ch_regs + (reg))
270 static inline struct at_xdmac_chan *to_at_xdmac_chan(struct dma_chan *dchan)
272 return container_of(dchan, struct at_xdmac_chan, chan);
275 static struct device *chan2dev(struct dma_chan *chan)
277 return &chan->dev->device;
280 static inline struct at_xdmac *to_at_xdmac(struct dma_device *ddev)
282 return container_of(ddev, struct at_xdmac, dma);
285 static inline struct at_xdmac_desc *txd_to_at_desc(struct dma_async_tx_descriptor *txd)
287 return container_of(txd, struct at_xdmac_desc, tx_dma_desc);
290 static inline int at_xdmac_chan_is_cyclic(struct at_xdmac_chan *atchan)
292 return test_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status);
295 static inline int at_xdmac_chan_is_paused(struct at_xdmac_chan *atchan)
297 return test_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
300 static inline int at_xdmac_csize(u32 maxburst)
304 csize = ffs(maxburst) - 1;
311 static inline bool at_xdmac_chan_is_peripheral_xfer(u32 cfg)
313 return cfg & AT_XDMAC_CC_TYPE_PER_TRAN;
316 static inline u8 at_xdmac_get_dwidth(u32 cfg)
318 return (cfg & AT_XDMAC_CC_DWIDTH_MASK) >> AT_XDMAC_CC_DWIDTH_OFFSET;
321 static unsigned int init_nr_desc_per_channel = 64;
322 module_param(init_nr_desc_per_channel, uint, 0644);
323 MODULE_PARM_DESC(init_nr_desc_per_channel,
324 "initial descriptors per channel (default: 64)");
327 static bool at_xdmac_chan_is_enabled(struct at_xdmac_chan *atchan)
329 return at_xdmac_chan_read(atchan, AT_XDMAC_GS) & atchan->mask;
332 static void at_xdmac_off(struct at_xdmac *atxdmac)
334 at_xdmac_write(atxdmac, AT_XDMAC_GD, -1L);
336 /* Wait that all chans are disabled. */
337 while (at_xdmac_read(atxdmac, AT_XDMAC_GS))
340 at_xdmac_write(atxdmac, AT_XDMAC_GID, -1L);
343 /* Call with lock hold. */
344 static void at_xdmac_start_xfer(struct at_xdmac_chan *atchan,
345 struct at_xdmac_desc *first)
347 struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
350 dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, first);
352 if (at_xdmac_chan_is_enabled(atchan))
355 /* Set transfer as active to not try to start it again. */
356 first->active_xfer = true;
358 /* Tell xdmac where to get the first descriptor. */
359 reg = AT_XDMAC_CNDA_NDA(first->tx_dma_desc.phys)
360 | AT_XDMAC_CNDA_NDAIF(atchan->memif);
361 at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, reg);
364 * When doing non cyclic transfer we need to use the next
365 * descriptor view 2 since some fields of the configuration register
366 * depend on transfer size and src/dest addresses.
368 if (at_xdmac_chan_is_cyclic(atchan))
369 reg = AT_XDMAC_CNDC_NDVIEW_NDV1;
370 else if (first->lld.mbr_ubc & AT_XDMAC_MBR_UBC_NDV3)
371 reg = AT_XDMAC_CNDC_NDVIEW_NDV3;
373 reg = AT_XDMAC_CNDC_NDVIEW_NDV2;
375 * Even if the register will be updated from the configuration in the
376 * descriptor when using view 2 or higher, the PROT bit won't be set
377 * properly. This bit can be modified only by using the channel
378 * configuration register.
380 at_xdmac_chan_write(atchan, AT_XDMAC_CC, first->lld.mbr_cfg);
382 reg |= AT_XDMAC_CNDC_NDDUP
383 | AT_XDMAC_CNDC_NDSUP
385 at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, reg);
387 dev_vdbg(chan2dev(&atchan->chan),
388 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
389 __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
390 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
391 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
392 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
393 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
394 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
396 at_xdmac_chan_write(atchan, AT_XDMAC_CID, 0xffffffff);
397 reg = AT_XDMAC_CIE_RBEIE | AT_XDMAC_CIE_WBEIE;
399 * Request Overflow Error is only for peripheral synchronized transfers
401 if (at_xdmac_chan_is_peripheral_xfer(first->lld.mbr_cfg))
402 reg |= AT_XDMAC_CIE_ROIE;
405 * There is no end of list when doing cyclic dma, we need to get
406 * an interrupt after each periods.
408 if (at_xdmac_chan_is_cyclic(atchan))
409 at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
410 reg | AT_XDMAC_CIE_BIE);
412 at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
413 reg | AT_XDMAC_CIE_LIE);
414 at_xdmac_write(atxdmac, AT_XDMAC_GIE, atchan->mask);
415 dev_vdbg(chan2dev(&atchan->chan),
416 "%s: enable channel (0x%08x)\n", __func__, atchan->mask);
418 at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
420 dev_vdbg(chan2dev(&atchan->chan),
421 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
422 __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
423 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
424 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
425 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
426 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
427 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
431 static dma_cookie_t at_xdmac_tx_submit(struct dma_async_tx_descriptor *tx)
433 struct at_xdmac_desc *desc = txd_to_at_desc(tx);
434 struct at_xdmac_chan *atchan = to_at_xdmac_chan(tx->chan);
436 unsigned long irqflags;
438 spin_lock_irqsave(&atchan->lock, irqflags);
439 cookie = dma_cookie_assign(tx);
441 dev_vdbg(chan2dev(tx->chan), "%s: atchan 0x%p, add desc 0x%p to xfers_list\n",
442 __func__, atchan, desc);
443 list_add_tail(&desc->xfer_node, &atchan->xfers_list);
444 if (list_is_singular(&atchan->xfers_list))
445 at_xdmac_start_xfer(atchan, desc);
447 spin_unlock_irqrestore(&atchan->lock, irqflags);
451 static struct at_xdmac_desc *at_xdmac_alloc_desc(struct dma_chan *chan,
454 struct at_xdmac_desc *desc;
455 struct at_xdmac *atxdmac = to_at_xdmac(chan->device);
458 desc = dma_pool_zalloc(atxdmac->at_xdmac_desc_pool, gfp_flags, &phys);
460 INIT_LIST_HEAD(&desc->descs_list);
461 dma_async_tx_descriptor_init(&desc->tx_dma_desc, chan);
462 desc->tx_dma_desc.tx_submit = at_xdmac_tx_submit;
463 desc->tx_dma_desc.phys = phys;
469 static void at_xdmac_init_used_desc(struct at_xdmac_desc *desc)
471 memset(&desc->lld, 0, sizeof(desc->lld));
472 INIT_LIST_HEAD(&desc->descs_list);
473 desc->direction = DMA_TRANS_NONE;
475 desc->active_xfer = false;
478 /* Call must be protected by lock. */
479 static struct at_xdmac_desc *at_xdmac_get_desc(struct at_xdmac_chan *atchan)
481 struct at_xdmac_desc *desc;
483 if (list_empty(&atchan->free_descs_list)) {
484 desc = at_xdmac_alloc_desc(&atchan->chan, GFP_NOWAIT);
486 desc = list_first_entry(&atchan->free_descs_list,
487 struct at_xdmac_desc, desc_node);
488 list_del(&desc->desc_node);
489 at_xdmac_init_used_desc(desc);
495 static void at_xdmac_queue_desc(struct dma_chan *chan,
496 struct at_xdmac_desc *prev,
497 struct at_xdmac_desc *desc)
502 prev->lld.mbr_nda = desc->tx_dma_desc.phys;
503 prev->lld.mbr_ubc |= AT_XDMAC_MBR_UBC_NDE;
505 dev_dbg(chan2dev(chan), "%s: chain lld: prev=0x%p, mbr_nda=%pad\n",
506 __func__, prev, &prev->lld.mbr_nda);
509 static inline void at_xdmac_increment_block_count(struct dma_chan *chan,
510 struct at_xdmac_desc *desc)
517 dev_dbg(chan2dev(chan),
518 "%s: incrementing the block count of the desc 0x%p\n",
522 static struct dma_chan *at_xdmac_xlate(struct of_phandle_args *dma_spec,
523 struct of_dma *of_dma)
525 struct at_xdmac *atxdmac = of_dma->of_dma_data;
526 struct at_xdmac_chan *atchan;
527 struct dma_chan *chan;
528 struct device *dev = atxdmac->dma.dev;
530 if (dma_spec->args_count != 1) {
531 dev_err(dev, "dma phandler args: bad number of args\n");
535 chan = dma_get_any_slave_channel(&atxdmac->dma);
537 dev_err(dev, "can't get a dma channel\n");
541 atchan = to_at_xdmac_chan(chan);
542 atchan->memif = AT91_XDMAC_DT_GET_MEM_IF(dma_spec->args[0]);
543 atchan->perif = AT91_XDMAC_DT_GET_PER_IF(dma_spec->args[0]);
544 atchan->perid = AT91_XDMAC_DT_GET_PERID(dma_spec->args[0]);
545 dev_dbg(dev, "chan dt cfg: memif=%u perif=%u perid=%u\n",
546 atchan->memif, atchan->perif, atchan->perid);
551 static int at_xdmac_compute_chan_conf(struct dma_chan *chan,
552 enum dma_transfer_direction direction)
554 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
557 if (direction == DMA_DEV_TO_MEM) {
559 AT91_XDMAC_DT_PERID(atchan->perid)
560 | AT_XDMAC_CC_DAM_INCREMENTED_AM
561 | AT_XDMAC_CC_SAM_FIXED_AM
562 | AT_XDMAC_CC_DIF(atchan->memif)
563 | AT_XDMAC_CC_SIF(atchan->perif)
564 | AT_XDMAC_CC_SWREQ_HWR_CONNECTED
565 | AT_XDMAC_CC_DSYNC_PER2MEM
566 | AT_XDMAC_CC_MBSIZE_SIXTEEN
567 | AT_XDMAC_CC_TYPE_PER_TRAN;
568 csize = ffs(atchan->sconfig.src_maxburst) - 1;
570 dev_err(chan2dev(chan), "invalid src maxburst value\n");
573 atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
574 dwidth = ffs(atchan->sconfig.src_addr_width) - 1;
576 dev_err(chan2dev(chan), "invalid src addr width value\n");
579 atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
580 } else if (direction == DMA_MEM_TO_DEV) {
582 AT91_XDMAC_DT_PERID(atchan->perid)
583 | AT_XDMAC_CC_DAM_FIXED_AM
584 | AT_XDMAC_CC_SAM_INCREMENTED_AM
585 | AT_XDMAC_CC_DIF(atchan->perif)
586 | AT_XDMAC_CC_SIF(atchan->memif)
587 | AT_XDMAC_CC_SWREQ_HWR_CONNECTED
588 | AT_XDMAC_CC_DSYNC_MEM2PER
589 | AT_XDMAC_CC_MBSIZE_SIXTEEN
590 | AT_XDMAC_CC_TYPE_PER_TRAN;
591 csize = ffs(atchan->sconfig.dst_maxburst) - 1;
593 dev_err(chan2dev(chan), "invalid src maxburst value\n");
596 atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
597 dwidth = ffs(atchan->sconfig.dst_addr_width) - 1;
599 dev_err(chan2dev(chan), "invalid dst addr width value\n");
602 atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
605 dev_dbg(chan2dev(chan), "%s: cfg=0x%08x\n", __func__, atchan->cfg);
611 * Only check that maxburst and addr width values are supported by the
612 * the controller but not that the configuration is good to perform the
613 * transfer since we don't know the direction at this stage.
615 static int at_xdmac_check_slave_config(struct dma_slave_config *sconfig)
617 if ((sconfig->src_maxburst > AT_XDMAC_MAX_CSIZE)
618 || (sconfig->dst_maxburst > AT_XDMAC_MAX_CSIZE))
621 if ((sconfig->src_addr_width > AT_XDMAC_MAX_DWIDTH)
622 || (sconfig->dst_addr_width > AT_XDMAC_MAX_DWIDTH))
628 static int at_xdmac_set_slave_config(struct dma_chan *chan,
629 struct dma_slave_config *sconfig)
631 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
633 if (at_xdmac_check_slave_config(sconfig)) {
634 dev_err(chan2dev(chan), "invalid slave configuration\n");
638 memcpy(&atchan->sconfig, sconfig, sizeof(atchan->sconfig));
643 static struct dma_async_tx_descriptor *
644 at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
645 unsigned int sg_len, enum dma_transfer_direction direction,
646 unsigned long flags, void *context)
648 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
649 struct at_xdmac_desc *first = NULL, *prev = NULL;
650 struct scatterlist *sg;
652 unsigned int xfer_size = 0;
653 unsigned long irqflags;
654 struct dma_async_tx_descriptor *ret = NULL;
659 if (!is_slave_direction(direction)) {
660 dev_err(chan2dev(chan), "invalid DMA direction\n");
664 dev_dbg(chan2dev(chan), "%s: sg_len=%d, dir=%s, flags=0x%lx\n",
666 direction == DMA_MEM_TO_DEV ? "to device" : "from device",
669 /* Protect dma_sconfig field that can be modified by set_slave_conf. */
670 spin_lock_irqsave(&atchan->lock, irqflags);
672 if (at_xdmac_compute_chan_conf(chan, direction))
675 /* Prepare descriptors. */
676 for_each_sg(sgl, sg, sg_len, i) {
677 struct at_xdmac_desc *desc = NULL;
678 u32 len, mem, dwidth, fixed_dwidth;
680 len = sg_dma_len(sg);
681 mem = sg_dma_address(sg);
682 if (unlikely(!len)) {
683 dev_err(chan2dev(chan), "sg data length is zero\n");
686 dev_dbg(chan2dev(chan), "%s: * sg%d len=%u, mem=0x%08x\n",
687 __func__, i, len, mem);
689 desc = at_xdmac_get_desc(atchan);
691 dev_err(chan2dev(chan), "can't get descriptor\n");
693 list_splice_init(&first->descs_list, &atchan->free_descs_list);
697 /* Linked list descriptor setup. */
698 if (direction == DMA_DEV_TO_MEM) {
699 desc->lld.mbr_sa = atchan->sconfig.src_addr;
700 desc->lld.mbr_da = mem;
702 desc->lld.mbr_sa = mem;
703 desc->lld.mbr_da = atchan->sconfig.dst_addr;
705 dwidth = at_xdmac_get_dwidth(atchan->cfg);
706 fixed_dwidth = IS_ALIGNED(len, 1 << dwidth)
708 : AT_XDMAC_CC_DWIDTH_BYTE;
709 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2 /* next descriptor view */
710 | AT_XDMAC_MBR_UBC_NDEN /* next descriptor dst parameter update */
711 | AT_XDMAC_MBR_UBC_NSEN /* next descriptor src parameter update */
712 | (len >> fixed_dwidth); /* microblock length */
713 desc->lld.mbr_cfg = (atchan->cfg & ~AT_XDMAC_CC_DWIDTH_MASK) |
714 AT_XDMAC_CC_DWIDTH(fixed_dwidth);
715 dev_dbg(chan2dev(chan),
716 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
717 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
721 at_xdmac_queue_desc(chan, prev, desc);
727 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
728 __func__, desc, first);
729 list_add_tail(&desc->desc_node, &first->descs_list);
734 first->tx_dma_desc.flags = flags;
735 first->xfer_size = xfer_size;
736 first->direction = direction;
737 ret = &first->tx_dma_desc;
740 spin_unlock_irqrestore(&atchan->lock, irqflags);
744 static struct dma_async_tx_descriptor *
745 at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr,
746 size_t buf_len, size_t period_len,
747 enum dma_transfer_direction direction,
750 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
751 struct at_xdmac_desc *first = NULL, *prev = NULL;
752 unsigned int periods = buf_len / period_len;
754 unsigned long irqflags;
756 dev_dbg(chan2dev(chan), "%s: buf_addr=%pad, buf_len=%zd, period_len=%zd, dir=%s, flags=0x%lx\n",
757 __func__, &buf_addr, buf_len, period_len,
758 direction == DMA_MEM_TO_DEV ? "mem2per" : "per2mem", flags);
760 if (!is_slave_direction(direction)) {
761 dev_err(chan2dev(chan), "invalid DMA direction\n");
765 if (test_and_set_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status)) {
766 dev_err(chan2dev(chan), "channel currently used\n");
770 if (at_xdmac_compute_chan_conf(chan, direction))
773 for (i = 0; i < periods; i++) {
774 struct at_xdmac_desc *desc = NULL;
776 spin_lock_irqsave(&atchan->lock, irqflags);
777 desc = at_xdmac_get_desc(atchan);
779 dev_err(chan2dev(chan), "can't get descriptor\n");
781 list_splice_init(&first->descs_list, &atchan->free_descs_list);
782 spin_unlock_irqrestore(&atchan->lock, irqflags);
785 spin_unlock_irqrestore(&atchan->lock, irqflags);
786 dev_dbg(chan2dev(chan),
787 "%s: desc=0x%p, tx_dma_desc.phys=%pad\n",
788 __func__, desc, &desc->tx_dma_desc.phys);
790 if (direction == DMA_DEV_TO_MEM) {
791 desc->lld.mbr_sa = atchan->sconfig.src_addr;
792 desc->lld.mbr_da = buf_addr + i * period_len;
794 desc->lld.mbr_sa = buf_addr + i * period_len;
795 desc->lld.mbr_da = atchan->sconfig.dst_addr;
797 desc->lld.mbr_cfg = atchan->cfg;
798 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV1
799 | AT_XDMAC_MBR_UBC_NDEN
800 | AT_XDMAC_MBR_UBC_NSEN
801 | period_len >> at_xdmac_get_dwidth(desc->lld.mbr_cfg);
803 dev_dbg(chan2dev(chan),
804 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
805 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
809 at_xdmac_queue_desc(chan, prev, desc);
815 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
816 __func__, desc, first);
817 list_add_tail(&desc->desc_node, &first->descs_list);
820 at_xdmac_queue_desc(chan, prev, first);
821 first->tx_dma_desc.flags = flags;
822 first->xfer_size = buf_len;
823 first->direction = direction;
825 return &first->tx_dma_desc;
828 static inline u32 at_xdmac_align_width(struct dma_chan *chan, dma_addr_t addr)
833 * Check address alignment to select the greater data width we
836 * Some XDMAC implementations don't provide dword transfer, in
837 * this case selecting dword has the same behavior as
838 * selecting word transfers.
841 width = AT_XDMAC_CC_DWIDTH_DWORD;
842 dev_dbg(chan2dev(chan), "%s: dwidth: double word\n", __func__);
843 } else if (!(addr & 3)) {
844 width = AT_XDMAC_CC_DWIDTH_WORD;
845 dev_dbg(chan2dev(chan), "%s: dwidth: word\n", __func__);
846 } else if (!(addr & 1)) {
847 width = AT_XDMAC_CC_DWIDTH_HALFWORD;
848 dev_dbg(chan2dev(chan), "%s: dwidth: half word\n", __func__);
850 width = AT_XDMAC_CC_DWIDTH_BYTE;
851 dev_dbg(chan2dev(chan), "%s: dwidth: byte\n", __func__);
857 static struct at_xdmac_desc *
858 at_xdmac_interleaved_queue_desc(struct dma_chan *chan,
859 struct at_xdmac_chan *atchan,
860 struct at_xdmac_desc *prev,
861 dma_addr_t src, dma_addr_t dst,
862 struct dma_interleaved_template *xt,
863 struct data_chunk *chunk)
865 struct at_xdmac_desc *desc;
870 * WARNING: The channel configuration is set here since there is no
871 * dmaengine_slave_config call in this case. Moreover we don't know the
872 * direction, it involves we can't dynamically set the source and dest
873 * interface so we have to use the same one. Only interface 0 allows EBI
874 * access. Hopefully we can access DDR through both ports (at least on
875 * SAMA5D4x), so we can use the same interface for source and dest,
876 * that solves the fact we don't know the direction.
877 * ERRATA: Even if useless for memory transfers, the PERID has to not
878 * match the one of another channel. If not, it could lead to spurious
881 u32 chan_cc = AT_XDMAC_CC_PERID(0x3f)
884 | AT_XDMAC_CC_MBSIZE_SIXTEEN
885 | AT_XDMAC_CC_TYPE_MEM_TRAN;
887 dwidth = at_xdmac_align_width(chan, src | dst | chunk->size);
888 if (chunk->size >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
889 dev_dbg(chan2dev(chan),
890 "%s: chunk too big (%zu, max size %lu)...\n",
891 __func__, chunk->size,
892 AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth);
897 dev_dbg(chan2dev(chan),
898 "Adding items at the end of desc 0x%p\n", prev);
902 chan_cc |= AT_XDMAC_CC_SAM_UBS_AM;
904 chan_cc |= AT_XDMAC_CC_SAM_INCREMENTED_AM;
909 chan_cc |= AT_XDMAC_CC_DAM_UBS_AM;
911 chan_cc |= AT_XDMAC_CC_DAM_INCREMENTED_AM;
914 spin_lock_irqsave(&atchan->lock, flags);
915 desc = at_xdmac_get_desc(atchan);
916 spin_unlock_irqrestore(&atchan->lock, flags);
918 dev_err(chan2dev(chan), "can't get descriptor\n");
922 chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
924 ublen = chunk->size >> dwidth;
926 desc->lld.mbr_sa = src;
927 desc->lld.mbr_da = dst;
928 desc->lld.mbr_sus = dmaengine_get_src_icg(xt, chunk);
929 desc->lld.mbr_dus = dmaengine_get_dst_icg(xt, chunk);
931 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
932 | AT_XDMAC_MBR_UBC_NDEN
933 | AT_XDMAC_MBR_UBC_NSEN
935 desc->lld.mbr_cfg = chan_cc;
937 dev_dbg(chan2dev(chan),
938 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
939 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da,
940 desc->lld.mbr_ubc, desc->lld.mbr_cfg);
944 at_xdmac_queue_desc(chan, prev, desc);
949 static struct dma_async_tx_descriptor *
950 at_xdmac_prep_interleaved(struct dma_chan *chan,
951 struct dma_interleaved_template *xt,
954 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
955 struct at_xdmac_desc *prev = NULL, *first = NULL;
956 dma_addr_t dst_addr, src_addr;
957 size_t src_skip = 0, dst_skip = 0, len = 0;
958 struct data_chunk *chunk;
961 if (!xt || !xt->numf || (xt->dir != DMA_MEM_TO_MEM))
965 * TODO: Handle the case where we have to repeat a chain of
968 if ((xt->numf > 1) && (xt->frame_size > 1))
971 dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, numf=%zu, frame_size=%zu, flags=0x%lx\n",
972 __func__, &xt->src_start, &xt->dst_start, xt->numf,
973 xt->frame_size, flags);
975 src_addr = xt->src_start;
976 dst_addr = xt->dst_start;
979 first = at_xdmac_interleaved_queue_desc(chan, atchan,
984 /* Length of the block is (BLEN+1) microblocks. */
985 for (i = 0; i < xt->numf - 1; i++)
986 at_xdmac_increment_block_count(chan, first);
988 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
989 __func__, first, first);
990 list_add_tail(&first->desc_node, &first->descs_list);
992 for (i = 0; i < xt->frame_size; i++) {
993 size_t src_icg = 0, dst_icg = 0;
994 struct at_xdmac_desc *desc;
998 dst_icg = dmaengine_get_dst_icg(xt, chunk);
999 src_icg = dmaengine_get_src_icg(xt, chunk);
1001 src_skip = chunk->size + src_icg;
1002 dst_skip = chunk->size + dst_icg;
1004 dev_dbg(chan2dev(chan),
1005 "%s: chunk size=%zu, src icg=%zu, dst icg=%zu\n",
1006 __func__, chunk->size, src_icg, dst_icg);
1008 desc = at_xdmac_interleaved_queue_desc(chan, atchan,
1013 list_splice_init(&first->descs_list,
1014 &atchan->free_descs_list);
1021 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1022 __func__, desc, first);
1023 list_add_tail(&desc->desc_node, &first->descs_list);
1026 src_addr += src_skip;
1029 dst_addr += dst_skip;
1036 first->tx_dma_desc.cookie = -EBUSY;
1037 first->tx_dma_desc.flags = flags;
1038 first->xfer_size = len;
1040 return &first->tx_dma_desc;
1043 static struct dma_async_tx_descriptor *
1044 at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
1045 size_t len, unsigned long flags)
1047 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1048 struct at_xdmac_desc *first = NULL, *prev = NULL;
1049 size_t remaining_size = len, xfer_size = 0, ublen;
1050 dma_addr_t src_addr = src, dst_addr = dest;
1053 * WARNING: We don't know the direction, it involves we can't
1054 * dynamically set the source and dest interface so we have to use the
1055 * same one. Only interface 0 allows EBI access. Hopefully we can
1056 * access DDR through both ports (at least on SAMA5D4x), so we can use
1057 * the same interface for source and dest, that solves the fact we
1058 * don't know the direction.
1059 * ERRATA: Even if useless for memory transfers, the PERID has to not
1060 * match the one of another channel. If not, it could lead to spurious
1063 u32 chan_cc = AT_XDMAC_CC_PERID(0x3f)
1064 | AT_XDMAC_CC_DAM_INCREMENTED_AM
1065 | AT_XDMAC_CC_SAM_INCREMENTED_AM
1066 | AT_XDMAC_CC_DIF(0)
1067 | AT_XDMAC_CC_SIF(0)
1068 | AT_XDMAC_CC_MBSIZE_SIXTEEN
1069 | AT_XDMAC_CC_TYPE_MEM_TRAN;
1070 unsigned long irqflags;
1072 dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, len=%zd, flags=0x%lx\n",
1073 __func__, &src, &dest, len, flags);
1078 dwidth = at_xdmac_align_width(chan, src_addr | dst_addr);
1080 /* Prepare descriptors. */
1081 while (remaining_size) {
1082 struct at_xdmac_desc *desc = NULL;
1084 dev_dbg(chan2dev(chan), "%s: remaining_size=%zu\n", __func__, remaining_size);
1086 spin_lock_irqsave(&atchan->lock, irqflags);
1087 desc = at_xdmac_get_desc(atchan);
1088 spin_unlock_irqrestore(&atchan->lock, irqflags);
1090 dev_err(chan2dev(chan), "can't get descriptor\n");
1092 list_splice_init(&first->descs_list, &atchan->free_descs_list);
1096 /* Update src and dest addresses. */
1097 src_addr += xfer_size;
1098 dst_addr += xfer_size;
1100 if (remaining_size >= AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)
1101 xfer_size = AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth;
1103 xfer_size = remaining_size;
1105 dev_dbg(chan2dev(chan), "%s: xfer_size=%zu\n", __func__, xfer_size);
1107 /* Check remaining length and change data width if needed. */
1108 dwidth = at_xdmac_align_width(chan,
1109 src_addr | dst_addr | xfer_size);
1110 chan_cc &= ~AT_XDMAC_CC_DWIDTH_MASK;
1111 chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1113 ublen = xfer_size >> dwidth;
1114 remaining_size -= xfer_size;
1116 desc->lld.mbr_sa = src_addr;
1117 desc->lld.mbr_da = dst_addr;
1118 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2
1119 | AT_XDMAC_MBR_UBC_NDEN
1120 | AT_XDMAC_MBR_UBC_NSEN
1122 desc->lld.mbr_cfg = chan_cc;
1124 dev_dbg(chan2dev(chan),
1125 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1126 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc, desc->lld.mbr_cfg);
1130 at_xdmac_queue_desc(chan, prev, desc);
1136 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1137 __func__, desc, first);
1138 list_add_tail(&desc->desc_node, &first->descs_list);
1141 first->tx_dma_desc.flags = flags;
1142 first->xfer_size = len;
1144 return &first->tx_dma_desc;
1147 static struct at_xdmac_desc *at_xdmac_memset_create_desc(struct dma_chan *chan,
1148 struct at_xdmac_chan *atchan,
1149 dma_addr_t dst_addr,
1153 struct at_xdmac_desc *desc;
1154 unsigned long flags;
1158 * WARNING: The channel configuration is set here since there is no
1159 * dmaengine_slave_config call in this case. Moreover we don't know the
1160 * direction, it involves we can't dynamically set the source and dest
1161 * interface so we have to use the same one. Only interface 0 allows EBI
1162 * access. Hopefully we can access DDR through both ports (at least on
1163 * SAMA5D4x), so we can use the same interface for source and dest,
1164 * that solves the fact we don't know the direction.
1165 * ERRATA: Even if useless for memory transfers, the PERID has to not
1166 * match the one of another channel. If not, it could lead to spurious
1169 u32 chan_cc = AT_XDMAC_CC_PERID(0x3f)
1170 | AT_XDMAC_CC_DAM_UBS_AM
1171 | AT_XDMAC_CC_SAM_INCREMENTED_AM
1172 | AT_XDMAC_CC_DIF(0)
1173 | AT_XDMAC_CC_SIF(0)
1174 | AT_XDMAC_CC_MBSIZE_SIXTEEN
1175 | AT_XDMAC_CC_MEMSET_HW_MODE
1176 | AT_XDMAC_CC_TYPE_MEM_TRAN;
1178 dwidth = at_xdmac_align_width(chan, dst_addr);
1180 if (len >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
1181 dev_err(chan2dev(chan),
1182 "%s: Transfer too large, aborting...\n",
1187 spin_lock_irqsave(&atchan->lock, flags);
1188 desc = at_xdmac_get_desc(atchan);
1189 spin_unlock_irqrestore(&atchan->lock, flags);
1191 dev_err(chan2dev(chan), "can't get descriptor\n");
1195 chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1197 ublen = len >> dwidth;
1199 desc->lld.mbr_da = dst_addr;
1200 desc->lld.mbr_ds = value;
1201 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
1202 | AT_XDMAC_MBR_UBC_NDEN
1203 | AT_XDMAC_MBR_UBC_NSEN
1205 desc->lld.mbr_cfg = chan_cc;
1207 dev_dbg(chan2dev(chan),
1208 "%s: lld: mbr_da=%pad, mbr_ds=0x%08x, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1209 __func__, &desc->lld.mbr_da, desc->lld.mbr_ds, desc->lld.mbr_ubc,
1215 static struct dma_async_tx_descriptor *
1216 at_xdmac_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value,
1217 size_t len, unsigned long flags)
1219 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1220 struct at_xdmac_desc *desc;
1222 dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%zu, pattern=0x%x, flags=0x%lx\n",
1223 __func__, &dest, len, value, flags);
1228 desc = at_xdmac_memset_create_desc(chan, atchan, dest, len, value);
1229 list_add_tail(&desc->desc_node, &desc->descs_list);
1231 desc->tx_dma_desc.cookie = -EBUSY;
1232 desc->tx_dma_desc.flags = flags;
1233 desc->xfer_size = len;
1235 return &desc->tx_dma_desc;
1238 static struct dma_async_tx_descriptor *
1239 at_xdmac_prep_dma_memset_sg(struct dma_chan *chan, struct scatterlist *sgl,
1240 unsigned int sg_len, int value,
1241 unsigned long flags)
1243 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1244 struct at_xdmac_desc *desc, *pdesc = NULL,
1245 *ppdesc = NULL, *first = NULL;
1246 struct scatterlist *sg, *psg = NULL, *ppsg = NULL;
1247 size_t stride = 0, pstride = 0, len = 0;
1253 dev_dbg(chan2dev(chan), "%s: sg_len=%d, value=0x%x, flags=0x%lx\n",
1254 __func__, sg_len, value, flags);
1256 /* Prepare descriptors. */
1257 for_each_sg(sgl, sg, sg_len, i) {
1258 dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%d, pattern=0x%x, flags=0x%lx\n",
1259 __func__, &sg_dma_address(sg), sg_dma_len(sg),
1261 desc = at_xdmac_memset_create_desc(chan, atchan,
1266 list_splice_init(&first->descs_list,
1267 &atchan->free_descs_list);
1272 /* Update our strides */
1275 stride = sg_dma_address(sg) -
1276 (sg_dma_address(psg) + sg_dma_len(psg));
1279 * The scatterlist API gives us only the address and
1280 * length of each elements.
1282 * Unfortunately, we don't have the stride, which we
1283 * will need to compute.
1285 * That make us end up in a situation like this one:
1286 * len stride len stride len
1287 * +-------+ +-------+ +-------+
1288 * | N-2 | | N-1 | | N |
1289 * +-------+ +-------+ +-------+
1291 * We need all these three elements (N-2, N-1 and N)
1292 * to actually take the decision on whether we need to
1293 * queue N-1 or reuse N-2.
1295 * We will only consider N if it is the last element.
1297 if (ppdesc && pdesc) {
1298 if ((stride == pstride) &&
1299 (sg_dma_len(ppsg) == sg_dma_len(psg))) {
1300 dev_dbg(chan2dev(chan),
1301 "%s: desc 0x%p can be merged with desc 0x%p\n",
1302 __func__, pdesc, ppdesc);
1305 * Increment the block count of the
1308 at_xdmac_increment_block_count(chan, ppdesc);
1309 ppdesc->lld.mbr_dus = stride;
1312 * Put back the N-1 descriptor in the
1313 * free descriptor list
1315 list_add_tail(&pdesc->desc_node,
1316 &atchan->free_descs_list);
1319 * Make our N-1 descriptor pointer
1320 * point to the N-2 since they were
1326 * Rule out the case where we don't have
1327 * pstride computed yet (our second sg
1330 * We also want to catch the case where there
1331 * would be a negative stride,
1333 } else if (pstride ||
1334 sg_dma_address(sg) < sg_dma_address(psg)) {
1336 * Queue the N-1 descriptor after the
1339 at_xdmac_queue_desc(chan, ppdesc, pdesc);
1342 * Add the N-1 descriptor to the list
1343 * of the descriptors used for this
1346 list_add_tail(&desc->desc_node,
1347 &first->descs_list);
1348 dev_dbg(chan2dev(chan),
1349 "%s: add desc 0x%p to descs_list 0x%p\n",
1350 __func__, desc, first);
1355 * If we are the last element, just see if we have the
1356 * same size than the previous element.
1358 * If so, we can merge it with the previous descriptor
1359 * since we don't care about the stride anymore.
1361 if ((i == (sg_len - 1)) &&
1362 sg_dma_len(psg) == sg_dma_len(sg)) {
1363 dev_dbg(chan2dev(chan),
1364 "%s: desc 0x%p can be merged with desc 0x%p\n",
1365 __func__, desc, pdesc);
1368 * Increment the block count of the N-1
1371 at_xdmac_increment_block_count(chan, pdesc);
1372 pdesc->lld.mbr_dus = stride;
1375 * Put back the N descriptor in the free
1378 list_add_tail(&desc->desc_node,
1379 &atchan->free_descs_list);
1382 /* Update our descriptors */
1386 /* Update our scatter pointers */
1390 len += sg_dma_len(sg);
1393 first->tx_dma_desc.cookie = -EBUSY;
1394 first->tx_dma_desc.flags = flags;
1395 first->xfer_size = len;
1397 return &first->tx_dma_desc;
1400 static enum dma_status
1401 at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
1402 struct dma_tx_state *txstate)
1404 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1405 struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
1406 struct at_xdmac_desc *desc, *_desc;
1407 struct list_head *descs_list;
1408 enum dma_status ret;
1410 u32 cur_nda, check_nda, cur_ubc, mask, value;
1412 unsigned long flags;
1415 ret = dma_cookie_status(chan, cookie, txstate);
1416 if (ret == DMA_COMPLETE)
1422 spin_lock_irqsave(&atchan->lock, flags);
1424 desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node);
1427 * If the transfer has not been started yet, don't need to compute the
1428 * residue, it's the transfer length.
1430 if (!desc->active_xfer) {
1431 dma_set_residue(txstate, desc->xfer_size);
1435 residue = desc->xfer_size;
1437 * Flush FIFO: only relevant when the transfer is source peripheral
1438 * synchronized. Flush is needed before reading CUBC because data in
1439 * the FIFO are not reported by CUBC. Reporting a residue of the
1440 * transfer length while we have data in FIFO can cause issue.
1441 * Usecase: atmel USART has a timeout which means I have received
1442 * characters but there is no more character received for a while. On
1443 * timeout, it requests the residue. If the data are in the DMA FIFO,
1444 * we will return a residue of the transfer length. It means no data
1445 * received. If an application is waiting for these data, it will hang
1446 * since we won't have another USART timeout without receiving new
1449 mask = AT_XDMAC_CC_TYPE | AT_XDMAC_CC_DSYNC;
1450 value = AT_XDMAC_CC_TYPE_PER_TRAN | AT_XDMAC_CC_DSYNC_PER2MEM;
1451 if ((desc->lld.mbr_cfg & mask) == value) {
1452 at_xdmac_write(atxdmac, AT_XDMAC_GSWF, atchan->mask);
1453 while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS))
1458 * The easiest way to compute the residue should be to pause the DMA
1459 * but doing this can lead to miss some data as some devices don't
1461 * We need to read several registers because:
1462 * - DMA is running therefore a descriptor change is possible while
1463 * reading these registers
1464 * - When the block transfer is done, the value of the CUBC register
1465 * is set to its initial value until the fetch of the next descriptor.
1466 * This value will corrupt the residue calculation so we have to skip
1469 * INITD -------- ------------
1470 * |____________________|
1471 * _______________________ _______________
1472 * NDA @desc2 \/ @desc3
1473 * _______________________/\_______________
1474 * __________ ___________ _______________
1475 * CUBC 0 \/ MAX desc1 \/ MAX desc2
1476 * __________/\___________/\_______________
1478 * Since descriptors are aligned on 64 bits, we can assume that
1479 * the update of NDA and CUBC is atomic.
1480 * Memory barriers are used to ensure the read order of the registers.
1481 * A max number of retries is set because unlikely it could never ends.
1483 for (retry = 0; retry < AT_XDMAC_RESIDUE_MAX_RETRIES; retry++) {
1484 check_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
1486 cur_ubc = at_xdmac_chan_read(atchan, AT_XDMAC_CUBC);
1488 initd = !!(at_xdmac_chan_read(atchan, AT_XDMAC_CC) & AT_XDMAC_CC_INITD);
1490 cur_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
1493 if ((check_nda == cur_nda) && initd)
1497 if (unlikely(retry >= AT_XDMAC_RESIDUE_MAX_RETRIES)) {
1503 * Flush FIFO: only relevant when the transfer is source peripheral
1504 * synchronized. Another flush is needed here because CUBC is updated
1505 * when the controller sends the data write command. It can lead to
1506 * report data that are not written in the memory or the device. The
1507 * FIFO flush ensures that data are really written.
1509 if ((desc->lld.mbr_cfg & mask) == value) {
1510 at_xdmac_write(atxdmac, AT_XDMAC_GSWF, atchan->mask);
1511 while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS))
1516 * Remove size of all microblocks already transferred and the current
1517 * one. Then add the remaining size to transfer of the current
1520 descs_list = &desc->descs_list;
1521 list_for_each_entry_safe(desc, _desc, descs_list, desc_node) {
1522 dwidth = at_xdmac_get_dwidth(desc->lld.mbr_cfg);
1523 residue -= (desc->lld.mbr_ubc & 0xffffff) << dwidth;
1524 if ((desc->lld.mbr_nda & 0xfffffffc) == cur_nda)
1527 residue += cur_ubc << dwidth;
1529 dma_set_residue(txstate, residue);
1531 dev_dbg(chan2dev(chan),
1532 "%s: desc=0x%p, tx_dma_desc.phys=%pad, tx_status=%d, cookie=%d, residue=%d\n",
1533 __func__, desc, &desc->tx_dma_desc.phys, ret, cookie, residue);
1536 spin_unlock_irqrestore(&atchan->lock, flags);
1540 /* Call must be protected by lock. */
1541 static void at_xdmac_remove_xfer(struct at_xdmac_chan *atchan,
1542 struct at_xdmac_desc *desc)
1544 dev_dbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1547 * Remove the transfer from the transfer list then move the transfer
1548 * descriptors into the free descriptors list.
1550 list_del(&desc->xfer_node);
1551 list_splice_init(&desc->descs_list, &atchan->free_descs_list);
1554 static void at_xdmac_advance_work(struct at_xdmac_chan *atchan)
1556 struct at_xdmac_desc *desc;
1557 unsigned long flags;
1559 spin_lock_irqsave(&atchan->lock, flags);
1562 * If channel is enabled, do nothing, advance_work will be triggered
1563 * after the interruption.
1565 if (!at_xdmac_chan_is_enabled(atchan) && !list_empty(&atchan->xfers_list)) {
1566 desc = list_first_entry(&atchan->xfers_list,
1567 struct at_xdmac_desc,
1569 dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1570 if (!desc->active_xfer)
1571 at_xdmac_start_xfer(atchan, desc);
1574 spin_unlock_irqrestore(&atchan->lock, flags);
1577 static void at_xdmac_handle_cyclic(struct at_xdmac_chan *atchan)
1579 struct at_xdmac_desc *desc;
1580 struct dma_async_tx_descriptor *txd;
1582 desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node);
1583 txd = &desc->tx_dma_desc;
1585 if (txd->flags & DMA_PREP_INTERRUPT)
1586 dmaengine_desc_get_callback_invoke(txd, NULL);
1589 static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)
1591 struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
1592 struct at_xdmac_desc *bad_desc;
1595 * The descriptor currently at the head of the active list is
1596 * broken. Since we don't have any way to report errors, we'll
1597 * just have to scream loudly and try to continue with other
1598 * descriptors queued (if any).
1600 if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
1601 dev_err(chan2dev(&atchan->chan), "read bus error!!!");
1602 if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
1603 dev_err(chan2dev(&atchan->chan), "write bus error!!!");
1604 if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
1605 dev_err(chan2dev(&atchan->chan), "request overflow error!!!");
1607 spin_lock_bh(&atchan->lock);
1609 /* Channel must be disabled first as it's not done automatically */
1610 at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1611 while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
1614 bad_desc = list_first_entry(&atchan->xfers_list,
1615 struct at_xdmac_desc,
1618 spin_unlock_bh(&atchan->lock);
1620 /* Print bad descriptor's details if needed */
1621 dev_dbg(chan2dev(&atchan->chan),
1622 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
1623 __func__, &bad_desc->lld.mbr_sa, &bad_desc->lld.mbr_da,
1624 bad_desc->lld.mbr_ubc);
1626 /* Then continue with usual descriptor management */
1629 static void at_xdmac_tasklet(unsigned long data)
1631 struct at_xdmac_chan *atchan = (struct at_xdmac_chan *)data;
1632 struct at_xdmac_desc *desc;
1635 dev_dbg(chan2dev(&atchan->chan), "%s: status=0x%08x\n",
1636 __func__, atchan->irq_status);
1638 error_mask = AT_XDMAC_CIS_RBEIS
1639 | AT_XDMAC_CIS_WBEIS
1640 | AT_XDMAC_CIS_ROIS;
1642 if (at_xdmac_chan_is_cyclic(atchan)) {
1643 at_xdmac_handle_cyclic(atchan);
1644 } else if ((atchan->irq_status & AT_XDMAC_CIS_LIS)
1645 || (atchan->irq_status & error_mask)) {
1646 struct dma_async_tx_descriptor *txd;
1648 if (atchan->irq_status & error_mask)
1649 at_xdmac_handle_error(atchan);
1651 spin_lock(&atchan->lock);
1652 desc = list_first_entry(&atchan->xfers_list,
1653 struct at_xdmac_desc,
1655 dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1656 if (!desc->active_xfer) {
1657 dev_err(chan2dev(&atchan->chan), "Xfer not active: exiting");
1658 spin_unlock(&atchan->lock);
1662 txd = &desc->tx_dma_desc;
1664 at_xdmac_remove_xfer(atchan, desc);
1665 spin_unlock(&atchan->lock);
1667 if (!at_xdmac_chan_is_cyclic(atchan)) {
1668 dma_cookie_complete(txd);
1669 if (txd->flags & DMA_PREP_INTERRUPT)
1670 dmaengine_desc_get_callback_invoke(txd, NULL);
1673 dma_run_dependencies(txd);
1675 at_xdmac_advance_work(atchan);
1679 static irqreturn_t at_xdmac_interrupt(int irq, void *dev_id)
1681 struct at_xdmac *atxdmac = (struct at_xdmac *)dev_id;
1682 struct at_xdmac_chan *atchan;
1683 u32 imr, status, pending;
1684 u32 chan_imr, chan_status;
1685 int i, ret = IRQ_NONE;
1688 imr = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
1689 status = at_xdmac_read(atxdmac, AT_XDMAC_GIS);
1690 pending = status & imr;
1692 dev_vdbg(atxdmac->dma.dev,
1693 "%s: status=0x%08x, imr=0x%08x, pending=0x%08x\n",
1694 __func__, status, imr, pending);
1699 /* We have to find which channel has generated the interrupt. */
1700 for (i = 0; i < atxdmac->dma.chancnt; i++) {
1701 if (!((1 << i) & pending))
1704 atchan = &atxdmac->chan[i];
1705 chan_imr = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
1706 chan_status = at_xdmac_chan_read(atchan, AT_XDMAC_CIS);
1707 atchan->irq_status = chan_status & chan_imr;
1708 dev_vdbg(atxdmac->dma.dev,
1709 "%s: chan%d: imr=0x%x, status=0x%x\n",
1710 __func__, i, chan_imr, chan_status);
1711 dev_vdbg(chan2dev(&atchan->chan),
1712 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
1714 at_xdmac_chan_read(atchan, AT_XDMAC_CC),
1715 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
1716 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
1717 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
1718 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
1719 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
1721 if (atchan->irq_status & (AT_XDMAC_CIS_RBEIS | AT_XDMAC_CIS_WBEIS))
1722 at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1724 tasklet_schedule(&atchan->tasklet);
1733 static void at_xdmac_issue_pending(struct dma_chan *chan)
1735 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1737 dev_dbg(chan2dev(&atchan->chan), "%s\n", __func__);
1739 if (!at_xdmac_chan_is_cyclic(atchan))
1740 at_xdmac_advance_work(atchan);
1745 static int at_xdmac_device_config(struct dma_chan *chan,
1746 struct dma_slave_config *config)
1748 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1750 unsigned long flags;
1752 dev_dbg(chan2dev(chan), "%s\n", __func__);
1754 spin_lock_irqsave(&atchan->lock, flags);
1755 ret = at_xdmac_set_slave_config(chan, config);
1756 spin_unlock_irqrestore(&atchan->lock, flags);
1761 static int at_xdmac_device_pause(struct dma_chan *chan)
1763 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1764 struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
1765 unsigned long flags;
1767 dev_dbg(chan2dev(chan), "%s\n", __func__);
1769 if (test_and_set_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status))
1772 spin_lock_irqsave(&atchan->lock, flags);
1773 at_xdmac_write(atxdmac, AT_XDMAC_GRWS, atchan->mask);
1774 while (at_xdmac_chan_read(atchan, AT_XDMAC_CC)
1775 & (AT_XDMAC_CC_WRIP | AT_XDMAC_CC_RDIP))
1777 spin_unlock_irqrestore(&atchan->lock, flags);
1782 static int at_xdmac_device_resume(struct dma_chan *chan)
1784 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1785 struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
1786 unsigned long flags;
1788 dev_dbg(chan2dev(chan), "%s\n", __func__);
1790 spin_lock_irqsave(&atchan->lock, flags);
1791 if (!at_xdmac_chan_is_paused(atchan)) {
1792 spin_unlock_irqrestore(&atchan->lock, flags);
1796 at_xdmac_write(atxdmac, AT_XDMAC_GRWR, atchan->mask);
1797 clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
1798 spin_unlock_irqrestore(&atchan->lock, flags);
1803 static int at_xdmac_device_terminate_all(struct dma_chan *chan)
1805 struct at_xdmac_desc *desc, *_desc;
1806 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1807 struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
1808 unsigned long flags;
1810 dev_dbg(chan2dev(chan), "%s\n", __func__);
1812 spin_lock_irqsave(&atchan->lock, flags);
1813 at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1814 while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
1817 /* Cancel all pending transfers. */
1818 list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node)
1819 at_xdmac_remove_xfer(atchan, desc);
1821 clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
1822 clear_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status);
1823 spin_unlock_irqrestore(&atchan->lock, flags);
1828 static int at_xdmac_alloc_chan_resources(struct dma_chan *chan)
1830 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1831 struct at_xdmac_desc *desc;
1833 unsigned long flags;
1835 spin_lock_irqsave(&atchan->lock, flags);
1837 if (at_xdmac_chan_is_enabled(atchan)) {
1838 dev_err(chan2dev(chan),
1839 "can't allocate channel resources (channel enabled)\n");
1844 if (!list_empty(&atchan->free_descs_list)) {
1845 dev_err(chan2dev(chan),
1846 "can't allocate channel resources (channel not free from a previous use)\n");
1851 for (i = 0; i < init_nr_desc_per_channel; i++) {
1852 desc = at_xdmac_alloc_desc(chan, GFP_ATOMIC);
1854 dev_warn(chan2dev(chan),
1855 "only %d descriptors have been allocated\n", i);
1858 list_add_tail(&desc->desc_node, &atchan->free_descs_list);
1861 dma_cookie_init(chan);
1863 dev_dbg(chan2dev(chan), "%s: allocated %d descriptors\n", __func__, i);
1866 spin_unlock_irqrestore(&atchan->lock, flags);
1870 static void at_xdmac_free_chan_resources(struct dma_chan *chan)
1872 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1873 struct at_xdmac *atxdmac = to_at_xdmac(chan->device);
1874 struct at_xdmac_desc *desc, *_desc;
1876 list_for_each_entry_safe(desc, _desc, &atchan->free_descs_list, desc_node) {
1877 dev_dbg(chan2dev(chan), "%s: freeing descriptor %p\n", __func__, desc);
1878 list_del(&desc->desc_node);
1879 dma_pool_free(atxdmac->at_xdmac_desc_pool, desc, desc->tx_dma_desc.phys);
1886 static int atmel_xdmac_prepare(struct device *dev)
1888 struct at_xdmac *atxdmac = dev_get_drvdata(dev);
1889 struct dma_chan *chan, *_chan;
1891 list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
1892 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1894 /* Wait for transfer completion, except in cyclic case. */
1895 if (at_xdmac_chan_is_enabled(atchan) && !at_xdmac_chan_is_cyclic(atchan))
1901 # define atmel_xdmac_prepare NULL
1904 #ifdef CONFIG_PM_SLEEP
1905 static int atmel_xdmac_suspend(struct device *dev)
1907 struct at_xdmac *atxdmac = dev_get_drvdata(dev);
1908 struct dma_chan *chan, *_chan;
1910 list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
1911 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1913 atchan->save_cc = at_xdmac_chan_read(atchan, AT_XDMAC_CC);
1914 if (at_xdmac_chan_is_cyclic(atchan)) {
1915 if (!at_xdmac_chan_is_paused(atchan))
1916 at_xdmac_device_pause(chan);
1917 atchan->save_cim = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
1918 atchan->save_cnda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA);
1919 atchan->save_cndc = at_xdmac_chan_read(atchan, AT_XDMAC_CNDC);
1922 atxdmac->save_gim = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
1924 at_xdmac_off(atxdmac);
1925 clk_disable_unprepare(atxdmac->clk);
1929 static int atmel_xdmac_resume(struct device *dev)
1931 struct at_xdmac *atxdmac = dev_get_drvdata(dev);
1932 struct at_xdmac_chan *atchan;
1933 struct dma_chan *chan, *_chan;
1937 ret = clk_prepare_enable(atxdmac->clk);
1941 /* Clear pending interrupts. */
1942 for (i = 0; i < atxdmac->dma.chancnt; i++) {
1943 atchan = &atxdmac->chan[i];
1944 while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
1948 at_xdmac_write(atxdmac, AT_XDMAC_GIE, atxdmac->save_gim);
1949 list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
1950 atchan = to_at_xdmac_chan(chan);
1951 at_xdmac_chan_write(atchan, AT_XDMAC_CC, atchan->save_cc);
1952 if (at_xdmac_chan_is_cyclic(atchan)) {
1953 if (at_xdmac_chan_is_paused(atchan))
1954 at_xdmac_device_resume(chan);
1955 at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, atchan->save_cnda);
1956 at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, atchan->save_cndc);
1957 at_xdmac_chan_write(atchan, AT_XDMAC_CIE, atchan->save_cim);
1959 at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
1964 #endif /* CONFIG_PM_SLEEP */
1966 static int at_xdmac_probe(struct platform_device *pdev)
1968 struct resource *res;
1969 struct at_xdmac *atxdmac;
1970 int irq, size, nr_channels, i, ret;
1974 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1978 irq = platform_get_irq(pdev, 0);
1982 base = devm_ioremap_resource(&pdev->dev, res);
1984 return PTR_ERR(base);
1987 * Read number of xdmac channels, read helper function can't be used
1988 * since atxdmac is not yet allocated and we need to know the number
1989 * of channels to do the allocation.
1991 reg = readl_relaxed(base + AT_XDMAC_GTYPE);
1992 nr_channels = AT_XDMAC_NB_CH(reg);
1993 if (nr_channels > AT_XDMAC_MAX_CHAN) {
1994 dev_err(&pdev->dev, "invalid number of channels (%u)\n",
1999 size = sizeof(*atxdmac);
2000 size += nr_channels * sizeof(struct at_xdmac_chan);
2001 atxdmac = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
2003 dev_err(&pdev->dev, "can't allocate at_xdmac structure\n");
2007 atxdmac->regs = base;
2010 atxdmac->clk = devm_clk_get(&pdev->dev, "dma_clk");
2011 if (IS_ERR(atxdmac->clk)) {
2012 dev_err(&pdev->dev, "can't get dma_clk\n");
2013 return PTR_ERR(atxdmac->clk);
2016 /* Do not use dev res to prevent races with tasklet */
2017 ret = request_irq(atxdmac->irq, at_xdmac_interrupt, 0, "at_xdmac", atxdmac);
2019 dev_err(&pdev->dev, "can't request irq\n");
2023 ret = clk_prepare_enable(atxdmac->clk);
2025 dev_err(&pdev->dev, "can't prepare or enable clock\n");
2029 atxdmac->at_xdmac_desc_pool =
2030 dmam_pool_create(dev_name(&pdev->dev), &pdev->dev,
2031 sizeof(struct at_xdmac_desc), 4, 0);
2032 if (!atxdmac->at_xdmac_desc_pool) {
2033 dev_err(&pdev->dev, "no memory for descriptors dma pool\n");
2035 goto err_clk_disable;
2038 dma_cap_set(DMA_CYCLIC, atxdmac->dma.cap_mask);
2039 dma_cap_set(DMA_INTERLEAVE, atxdmac->dma.cap_mask);
2040 dma_cap_set(DMA_MEMCPY, atxdmac->dma.cap_mask);
2041 dma_cap_set(DMA_MEMSET, atxdmac->dma.cap_mask);
2042 dma_cap_set(DMA_MEMSET_SG, atxdmac->dma.cap_mask);
2043 dma_cap_set(DMA_SLAVE, atxdmac->dma.cap_mask);
2045 * Without DMA_PRIVATE the driver is not able to allocate more than
2046 * one channel, second allocation fails in private_candidate.
2048 dma_cap_set(DMA_PRIVATE, atxdmac->dma.cap_mask);
2049 atxdmac->dma.dev = &pdev->dev;
2050 atxdmac->dma.device_alloc_chan_resources = at_xdmac_alloc_chan_resources;
2051 atxdmac->dma.device_free_chan_resources = at_xdmac_free_chan_resources;
2052 atxdmac->dma.device_tx_status = at_xdmac_tx_status;
2053 atxdmac->dma.device_issue_pending = at_xdmac_issue_pending;
2054 atxdmac->dma.device_prep_dma_cyclic = at_xdmac_prep_dma_cyclic;
2055 atxdmac->dma.device_prep_interleaved_dma = at_xdmac_prep_interleaved;
2056 atxdmac->dma.device_prep_dma_memcpy = at_xdmac_prep_dma_memcpy;
2057 atxdmac->dma.device_prep_dma_memset = at_xdmac_prep_dma_memset;
2058 atxdmac->dma.device_prep_dma_memset_sg = at_xdmac_prep_dma_memset_sg;
2059 atxdmac->dma.device_prep_slave_sg = at_xdmac_prep_slave_sg;
2060 atxdmac->dma.device_config = at_xdmac_device_config;
2061 atxdmac->dma.device_pause = at_xdmac_device_pause;
2062 atxdmac->dma.device_resume = at_xdmac_device_resume;
2063 atxdmac->dma.device_terminate_all = at_xdmac_device_terminate_all;
2064 atxdmac->dma.src_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
2065 atxdmac->dma.dst_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
2066 atxdmac->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
2067 atxdmac->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
2069 /* Disable all chans and interrupts. */
2070 at_xdmac_off(atxdmac);
2072 /* Init channels. */
2073 INIT_LIST_HEAD(&atxdmac->dma.channels);
2074 for (i = 0; i < nr_channels; i++) {
2075 struct at_xdmac_chan *atchan = &atxdmac->chan[i];
2077 atchan->chan.device = &atxdmac->dma;
2078 list_add_tail(&atchan->chan.device_node,
2079 &atxdmac->dma.channels);
2081 atchan->ch_regs = at_xdmac_chan_reg_base(atxdmac, i);
2082 atchan->mask = 1 << i;
2084 spin_lock_init(&atchan->lock);
2085 INIT_LIST_HEAD(&atchan->xfers_list);
2086 INIT_LIST_HEAD(&atchan->free_descs_list);
2087 tasklet_init(&atchan->tasklet, at_xdmac_tasklet,
2088 (unsigned long)atchan);
2090 /* Clear pending interrupts. */
2091 while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
2094 platform_set_drvdata(pdev, atxdmac);
2096 ret = dma_async_device_register(&atxdmac->dma);
2098 dev_err(&pdev->dev, "fail to register DMA engine device\n");
2099 goto err_clk_disable;
2102 ret = of_dma_controller_register(pdev->dev.of_node,
2103 at_xdmac_xlate, atxdmac);
2105 dev_err(&pdev->dev, "could not register of dma controller\n");
2106 goto err_dma_unregister;
2109 dev_info(&pdev->dev, "%d channels, mapped at 0x%p\n",
2110 nr_channels, atxdmac->regs);
2115 dma_async_device_unregister(&atxdmac->dma);
2117 clk_disable_unprepare(atxdmac->clk);
2119 free_irq(atxdmac->irq, atxdmac);
2123 static int at_xdmac_remove(struct platform_device *pdev)
2125 struct at_xdmac *atxdmac = (struct at_xdmac *)platform_get_drvdata(pdev);
2128 at_xdmac_off(atxdmac);
2129 of_dma_controller_free(pdev->dev.of_node);
2130 dma_async_device_unregister(&atxdmac->dma);
2131 clk_disable_unprepare(atxdmac->clk);
2133 free_irq(atxdmac->irq, atxdmac);
2135 for (i = 0; i < atxdmac->dma.chancnt; i++) {
2136 struct at_xdmac_chan *atchan = &atxdmac->chan[i];
2138 tasklet_kill(&atchan->tasklet);
2139 at_xdmac_free_chan_resources(&atchan->chan);
2145 static const struct dev_pm_ops atmel_xdmac_dev_pm_ops = {
2146 .prepare = atmel_xdmac_prepare,
2147 SET_LATE_SYSTEM_SLEEP_PM_OPS(atmel_xdmac_suspend, atmel_xdmac_resume)
2150 static const struct of_device_id atmel_xdmac_dt_ids[] = {
2152 .compatible = "atmel,sama5d4-dma",
2157 MODULE_DEVICE_TABLE(of, atmel_xdmac_dt_ids);
2159 static struct platform_driver at_xdmac_driver = {
2160 .probe = at_xdmac_probe,
2161 .remove = at_xdmac_remove,
2164 .of_match_table = of_match_ptr(atmel_xdmac_dt_ids),
2165 .pm = &atmel_xdmac_dev_pm_ops,
2169 static int __init at_xdmac_init(void)
2171 return platform_driver_probe(&at_xdmac_driver, at_xdmac_probe);
2173 subsys_initcall(at_xdmac_init);
2175 MODULE_DESCRIPTION("Atmel Extended DMA Controller driver");
2176 MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>");
2177 MODULE_LICENSE("GPL");