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Merge tag 'thunderbolt-fix-for-v5.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel...
[linux/fpc-iii.git] / drivers / dma / at_xdmac.c
blobf71c9f77d40594e08f02642d73038ec1eadf4216
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Driver for the Atmel Extensible DMA Controller (aka XDMAC on AT91 systems)
4 *
5 * Copyright (C) 2014 Atmel Corporation
6 *
7 * Author: Ludovic Desroches <ludovic.desroches@atmel.com>
8 */
9
10 #include <asm/barrier.h>
11 #include <dt-bindings/dma/at91.h>
12 #include <linux/clk.h>
13 #include <linux/dmaengine.h>
14 #include <linux/dmapool.h>
15 #include <linux/interrupt.h>
16 #include <linux/irq.h>
17 #include <linux/kernel.h>
18 #include <linux/list.h>
19 #include <linux/module.h>
20 #include <linux/of_dma.h>
21 #include <linux/of_platform.h>
22 #include <linux/platform_device.h>
23 #include <linux/pm.h>
24
25 #include "dmaengine.h"
26
27 /* Global registers */
28 #define AT_XDMAC_GTYPE 0x00 /* Global Type Register */
29 #define AT_XDMAC_NB_CH(i) (((i) & 0x1F) + 1) /* Number of Channels Minus One */
30 #define AT_XDMAC_FIFO_SZ(i) (((i) >> 5) & 0x7FF) /* Number of Bytes */
31 #define AT_XDMAC_NB_REQ(i) ((((i) >> 16) & 0x3F) + 1) /* Number of Peripheral Requests Minus One */
32 #define AT_XDMAC_GCFG 0x04 /* Global Configuration Register */
33 #define AT_XDMAC_GWAC 0x08 /* Global Weighted Arbiter Configuration Register */
34 #define AT_XDMAC_GIE 0x0C /* Global Interrupt Enable Register */
35 #define AT_XDMAC_GID 0x10 /* Global Interrupt Disable Register */
36 #define AT_XDMAC_GIM 0x14 /* Global Interrupt Mask Register */
37 #define AT_XDMAC_GIS 0x18 /* Global Interrupt Status Register */
38 #define AT_XDMAC_GE 0x1C /* Global Channel Enable Register */
39 #define AT_XDMAC_GD 0x20 /* Global Channel Disable Register */
40 #define AT_XDMAC_GS 0x24 /* Global Channel Status Register */
41 #define AT_XDMAC_GRS 0x28 /* Global Channel Read Suspend Register */
42 #define AT_XDMAC_GWS 0x2C /* Global Write Suspend Register */
43 #define AT_XDMAC_GRWS 0x30 /* Global Channel Read Write Suspend Register */
44 #define AT_XDMAC_GRWR 0x34 /* Global Channel Read Write Resume Register */
45 #define AT_XDMAC_GSWR 0x38 /* Global Channel Software Request Register */
46 #define AT_XDMAC_GSWS 0x3C /* Global channel Software Request Status Register */
47 #define AT_XDMAC_GSWF 0x40 /* Global Channel Software Flush Request Register */
48 #define AT_XDMAC_VERSION 0xFFC /* XDMAC Version Register */
49
50 /* Channel relative registers offsets */
51 #define AT_XDMAC_CIE 0x00 /* Channel Interrupt Enable Register */
52 #define AT_XDMAC_CIE_BIE BIT(0) /* End of Block Interrupt Enable Bit */
53 #define AT_XDMAC_CIE_LIE BIT(1) /* End of Linked List Interrupt Enable Bit */
54 #define AT_XDMAC_CIE_DIE BIT(2) /* End of Disable Interrupt Enable Bit */
55 #define AT_XDMAC_CIE_FIE BIT(3) /* End of Flush Interrupt Enable Bit */
56 #define AT_XDMAC_CIE_RBEIE BIT(4) /* Read Bus Error Interrupt Enable Bit */
57 #define AT_XDMAC_CIE_WBEIE BIT(5) /* Write Bus Error Interrupt Enable Bit */
58 #define AT_XDMAC_CIE_ROIE BIT(6) /* Request Overflow Interrupt Enable Bit */
59 #define AT_XDMAC_CID 0x04 /* Channel Interrupt Disable Register */
60 #define AT_XDMAC_CID_BID BIT(0) /* End of Block Interrupt Disable Bit */
61 #define AT_XDMAC_CID_LID BIT(1) /* End of Linked List Interrupt Disable Bit */
62 #define AT_XDMAC_CID_DID BIT(2) /* End of Disable Interrupt Disable Bit */
63 #define AT_XDMAC_CID_FID BIT(3) /* End of Flush Interrupt Disable Bit */
64 #define AT_XDMAC_CID_RBEID BIT(4) /* Read Bus Error Interrupt Disable Bit */
65 #define AT_XDMAC_CID_WBEID BIT(5) /* Write Bus Error Interrupt Disable Bit */
66 #define AT_XDMAC_CID_ROID BIT(6) /* Request Overflow Interrupt Disable Bit */
67 #define AT_XDMAC_CIM 0x08 /* Channel Interrupt Mask Register */
68 #define AT_XDMAC_CIM_BIM BIT(0) /* End of Block Interrupt Mask Bit */
69 #define AT_XDMAC_CIM_LIM BIT(1) /* End of Linked List Interrupt Mask Bit */
70 #define AT_XDMAC_CIM_DIM BIT(2) /* End of Disable Interrupt Mask Bit */
71 #define AT_XDMAC_CIM_FIM BIT(3) /* End of Flush Interrupt Mask Bit */
72 #define AT_XDMAC_CIM_RBEIM BIT(4) /* Read Bus Error Interrupt Mask Bit */
73 #define AT_XDMAC_CIM_WBEIM BIT(5) /* Write Bus Error Interrupt Mask Bit */
74 #define AT_XDMAC_CIM_ROIM BIT(6) /* Request Overflow Interrupt Mask Bit */
75 #define AT_XDMAC_CIS 0x0C /* Channel Interrupt Status Register */
76 #define AT_XDMAC_CIS_BIS BIT(0) /* End of Block Interrupt Status Bit */
77 #define AT_XDMAC_CIS_LIS BIT(1) /* End of Linked List Interrupt Status Bit */
78 #define AT_XDMAC_CIS_DIS BIT(2) /* End of Disable Interrupt Status Bit */
79 #define AT_XDMAC_CIS_FIS BIT(3) /* End of Flush Interrupt Status Bit */
80 #define AT_XDMAC_CIS_RBEIS BIT(4) /* Read Bus Error Interrupt Status Bit */
81 #define AT_XDMAC_CIS_WBEIS BIT(5) /* Write Bus Error Interrupt Status Bit */
82 #define AT_XDMAC_CIS_ROIS BIT(6) /* Request Overflow Interrupt Status Bit */
83 #define AT_XDMAC_CSA 0x10 /* Channel Source Address Register */
84 #define AT_XDMAC_CDA 0x14 /* Channel Destination Address Register */
85 #define AT_XDMAC_CNDA 0x18 /* Channel Next Descriptor Address Register */
86 #define AT_XDMAC_CNDA_NDAIF(i) ((i) & 0x1) /* Channel x Next Descriptor Interface */
87 #define AT_XDMAC_CNDA_NDA(i) ((i) & 0xfffffffc) /* Channel x Next Descriptor Address */
88 #define AT_XDMAC_CNDC 0x1C /* Channel Next Descriptor Control Register */
89 #define AT_XDMAC_CNDC_NDE (0x1 << 0) /* Channel x Next Descriptor Enable */
90 #define AT_XDMAC_CNDC_NDSUP (0x1 << 1) /* Channel x Next Descriptor Source Update */
91 #define AT_XDMAC_CNDC_NDDUP (0x1 << 2) /* Channel x Next Descriptor Destination Update */
92 #define AT_XDMAC_CNDC_NDVIEW_NDV0 (0x0 << 3) /* Channel x Next Descriptor View 0 */
93 #define AT_XDMAC_CNDC_NDVIEW_NDV1 (0x1 << 3) /* Channel x Next Descriptor View 1 */
94 #define AT_XDMAC_CNDC_NDVIEW_NDV2 (0x2 << 3) /* Channel x Next Descriptor View 2 */
95 #define AT_XDMAC_CNDC_NDVIEW_NDV3 (0x3 << 3) /* Channel x Next Descriptor View 3 */
96 #define AT_XDMAC_CUBC 0x20 /* Channel Microblock Control Register */
97 #define AT_XDMAC_CBC 0x24 /* Channel Block Control Register */
98 #define AT_XDMAC_CC 0x28 /* Channel Configuration Register */
99 #define AT_XDMAC_CC_TYPE (0x1 << 0) /* Channel Transfer Type */
100 #define AT_XDMAC_CC_TYPE_MEM_TRAN (0x0 << 0) /* Memory to Memory Transfer */
101 #define AT_XDMAC_CC_TYPE_PER_TRAN (0x1 << 0) /* Peripheral to Memory or Memory to Peripheral Transfer */
102 #define AT_XDMAC_CC_MBSIZE_MASK (0x3 << 1)
103 #define AT_XDMAC_CC_MBSIZE_SINGLE (0x0 << 1)
104 #define AT_XDMAC_CC_MBSIZE_FOUR (0x1 << 1)
105 #define AT_XDMAC_CC_MBSIZE_EIGHT (0x2 << 1)
106 #define AT_XDMAC_CC_MBSIZE_SIXTEEN (0x3 << 1)
107 #define AT_XDMAC_CC_DSYNC (0x1 << 4) /* Channel Synchronization */
108 #define AT_XDMAC_CC_DSYNC_PER2MEM (0x0 << 4)
109 #define AT_XDMAC_CC_DSYNC_MEM2PER (0x1 << 4)
110 #define AT_XDMAC_CC_PROT (0x1 << 5) /* Channel Protection */
111 #define AT_XDMAC_CC_PROT_SEC (0x0 << 5)
112 #define AT_XDMAC_CC_PROT_UNSEC (0x1 << 5)
113 #define AT_XDMAC_CC_SWREQ (0x1 << 6) /* Channel Software Request Trigger */
114 #define AT_XDMAC_CC_SWREQ_HWR_CONNECTED (0x0 << 6)
115 #define AT_XDMAC_CC_SWREQ_SWR_CONNECTED (0x1 << 6)
116 #define AT_XDMAC_CC_MEMSET (0x1 << 7) /* Channel Fill Block of memory */
117 #define AT_XDMAC_CC_MEMSET_NORMAL_MODE (0x0 << 7)
118 #define AT_XDMAC_CC_MEMSET_HW_MODE (0x1 << 7)
119 #define AT_XDMAC_CC_CSIZE(i) ((0x7 & (i)) << 8) /* Channel Chunk Size */
120 #define AT_XDMAC_CC_DWIDTH_OFFSET 11
121 #define AT_XDMAC_CC_DWIDTH_MASK (0x3 << AT_XDMAC_CC_DWIDTH_OFFSET)
122 #define AT_XDMAC_CC_DWIDTH(i) ((0x3 & (i)) << AT_XDMAC_CC_DWIDTH_OFFSET) /* Channel Data Width */
123 #define AT_XDMAC_CC_DWIDTH_BYTE 0x0
124 #define AT_XDMAC_CC_DWIDTH_HALFWORD 0x1
125 #define AT_XDMAC_CC_DWIDTH_WORD 0x2
126 #define AT_XDMAC_CC_DWIDTH_DWORD 0x3
127 #define AT_XDMAC_CC_SIF(i) ((0x1 & (i)) << 13) /* Channel Source Interface Identifier */
128 #define AT_XDMAC_CC_DIF(i) ((0x1 & (i)) << 14) /* Channel Destination Interface Identifier */
129 #define AT_XDMAC_CC_SAM_MASK (0x3 << 16) /* Channel Source Addressing Mode */
130 #define AT_XDMAC_CC_SAM_FIXED_AM (0x0 << 16)
131 #define AT_XDMAC_CC_SAM_INCREMENTED_AM (0x1 << 16)
132 #define AT_XDMAC_CC_SAM_UBS_AM (0x2 << 16)
133 #define AT_XDMAC_CC_SAM_UBS_DS_AM (0x3 << 16)
134 #define AT_XDMAC_CC_DAM_MASK (0x3 << 18) /* Channel Source Addressing Mode */
135 #define AT_XDMAC_CC_DAM_FIXED_AM (0x0 << 18)
136 #define AT_XDMAC_CC_DAM_INCREMENTED_AM (0x1 << 18)
137 #define AT_XDMAC_CC_DAM_UBS_AM (0x2 << 18)
138 #define AT_XDMAC_CC_DAM_UBS_DS_AM (0x3 << 18)
139 #define AT_XDMAC_CC_INITD (0x1 << 21) /* Channel Initialization Terminated (read only) */
140 #define AT_XDMAC_CC_INITD_TERMINATED (0x0 << 21)
141 #define AT_XDMAC_CC_INITD_IN_PROGRESS (0x1 << 21)
142 #define AT_XDMAC_CC_RDIP (0x1 << 22) /* Read in Progress (read only) */
143 #define AT_XDMAC_CC_RDIP_DONE (0x0 << 22)
144 #define AT_XDMAC_CC_RDIP_IN_PROGRESS (0x1 << 22)
145 #define AT_XDMAC_CC_WRIP (0x1 << 23) /* Write in Progress (read only) */
146 #define AT_XDMAC_CC_WRIP_DONE (0x0 << 23)
147 #define AT_XDMAC_CC_WRIP_IN_PROGRESS (0x1 << 23)
148 #define AT_XDMAC_CC_PERID(i) (0x7f & (i) << 24) /* Channel Peripheral Identifier */
149 #define AT_XDMAC_CDS_MSP 0x2C /* Channel Data Stride Memory Set Pattern */
150 #define AT_XDMAC_CSUS 0x30 /* Channel Source Microblock Stride */
151 #define AT_XDMAC_CDUS 0x34 /* Channel Destination Microblock Stride */
152
153 #define AT_XDMAC_CHAN_REG_BASE 0x50 /* Channel registers base address */
154
155 /* Microblock control members */
156 #define AT_XDMAC_MBR_UBC_UBLEN_MAX 0xFFFFFFUL /* Maximum Microblock Length */
157 #define AT_XDMAC_MBR_UBC_NDE (0x1 << 24) /* Next Descriptor Enable */
158 #define AT_XDMAC_MBR_UBC_NSEN (0x1 << 25) /* Next Descriptor Source Update */
159 #define AT_XDMAC_MBR_UBC_NDEN (0x1 << 26) /* Next Descriptor Destination Update */
160 #define AT_XDMAC_MBR_UBC_NDV0 (0x0 << 27) /* Next Descriptor View 0 */
161 #define AT_XDMAC_MBR_UBC_NDV1 (0x1 << 27) /* Next Descriptor View 1 */
162 #define AT_XDMAC_MBR_UBC_NDV2 (0x2 << 27) /* Next Descriptor View 2 */
163 #define AT_XDMAC_MBR_UBC_NDV3 (0x3 << 27) /* Next Descriptor View 3 */
164
165 #define AT_XDMAC_MAX_CHAN 0x20
166 #define AT_XDMAC_MAX_CSIZE 16 /* 16 data */
167 #define AT_XDMAC_MAX_DWIDTH 8 /* 64 bits */
168 #define AT_XDMAC_RESIDUE_MAX_RETRIES 5
169
170 #define AT_XDMAC_DMA_BUSWIDTHS\
171 (BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) |\
172 BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |\
173 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |\
174 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |\
175 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES))
176
177 enum atc_status {
178 AT_XDMAC_CHAN_IS_CYCLIC = 0,
179 AT_XDMAC_CHAN_IS_PAUSED,
180 };
181
182 /* ----- Channels ----- */
183 struct at_xdmac_chan {
184 struct dma_chan chan;
185 void __iomem *ch_regs;
186 u32 mask; /* Channel Mask */
187 u32 cfg; /* Channel Configuration Register */
188 u8 perid; /* Peripheral ID */
189 u8 perif; /* Peripheral Interface */
190 u8 memif; /* Memory Interface */
191 u32 save_cc;
192 u32 save_cim;
193 u32 save_cnda;
194 u32 save_cndc;
195 u32 irq_status;
196 unsigned long status;
197 struct tasklet_struct tasklet;
198 struct dma_slave_config sconfig;
199
200 spinlock_t lock;
201
202 struct list_head xfers_list;
203 struct list_head free_descs_list;
204 };
205
206
207 /* ----- Controller ----- */
208 struct at_xdmac {
209 struct dma_device dma;
210 void __iomem *regs;
211 int irq;
212 struct clk *clk;
213 u32 save_gim;
214 struct dma_pool *at_xdmac_desc_pool;
215 struct at_xdmac_chan chan[0];
216 };
217
218
219 /* ----- Descriptors ----- */
220
221 /* Linked List Descriptor */
222 struct at_xdmac_lld {
223 dma_addr_t mbr_nda; /* Next Descriptor Member */
224 u32 mbr_ubc; /* Microblock Control Member */
225 dma_addr_t mbr_sa; /* Source Address Member */
226 dma_addr_t mbr_da; /* Destination Address Member */
227 u32 mbr_cfg; /* Configuration Register */
228 u32 mbr_bc; /* Block Control Register */
229 u32 mbr_ds; /* Data Stride Register */
230 u32 mbr_sus; /* Source Microblock Stride Register */
231 u32 mbr_dus; /* Destination Microblock Stride Register */
232 };
233
234 /* 64-bit alignment needed to update CNDA and CUBC registers in an atomic way. */
235 struct at_xdmac_desc {
236 struct at_xdmac_lld lld;
237 enum dma_transfer_direction direction;
238 struct dma_async_tx_descriptor tx_dma_desc;
239 struct list_head desc_node;
240 /* Following members are only used by the first descriptor */
241 bool active_xfer;
242 unsigned int xfer_size;
243 struct list_head descs_list;
244 struct list_head xfer_node;
245 } __aligned(sizeof(u64));
246
247 static inline void __iomem *at_xdmac_chan_reg_base(struct at_xdmac *atxdmac, unsigned int chan_nb)
248 {
249 return atxdmac->regs + (AT_XDMAC_CHAN_REG_BASE + chan_nb * 0x40);
250 }
251
252 #define at_xdmac_read(atxdmac, reg) readl_relaxed((atxdmac)->regs + (reg))
253 #define at_xdmac_write(atxdmac, reg, value) \
254 writel_relaxed((value), (atxdmac)->regs + (reg))
255
256 #define at_xdmac_chan_read(atchan, reg) readl_relaxed((atchan)->ch_regs + (reg))
257 #define at_xdmac_chan_write(atchan, reg, value) writel_relaxed((value), (atchan)->ch_regs + (reg))
258
259 static inline struct at_xdmac_chan *to_at_xdmac_chan(struct dma_chan *dchan)
260 {
261 return container_of(dchan, struct at_xdmac_chan, chan);
262 }
263
264 static struct device *chan2dev(struct dma_chan *chan)
265 {
266 return &chan->dev->device;
267 }
268
269 static inline struct at_xdmac *to_at_xdmac(struct dma_device *ddev)
270 {
271 return container_of(ddev, struct at_xdmac, dma);
272 }
273
274 static inline struct at_xdmac_desc *txd_to_at_desc(struct dma_async_tx_descriptor *txd)
275 {
276 return container_of(txd, struct at_xdmac_desc, tx_dma_desc);
277 }
278
279 static inline int at_xdmac_chan_is_cyclic(struct at_xdmac_chan *atchan)
280 {
281 return test_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status);
282 }
283
284 static inline int at_xdmac_chan_is_paused(struct at_xdmac_chan *atchan)
285 {
286 return test_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
287 }
288
289 static inline int at_xdmac_csize(u32 maxburst)
290 {
291 int csize;
292
293 csize = ffs(maxburst) - 1;
294 if (csize > 4)
295 csize = -EINVAL;
296
297 return csize;
298 };
299
300 static inline bool at_xdmac_chan_is_peripheral_xfer(u32 cfg)
301 {
302 return cfg & AT_XDMAC_CC_TYPE_PER_TRAN;
303 }
304
305 static inline u8 at_xdmac_get_dwidth(u32 cfg)
306 {
307 return (cfg & AT_XDMAC_CC_DWIDTH_MASK) >> AT_XDMAC_CC_DWIDTH_OFFSET;
308 };
309
310 static unsigned int init_nr_desc_per_channel = 64;
311 module_param(init_nr_desc_per_channel, uint, 0644);
312 MODULE_PARM_DESC(init_nr_desc_per_channel,
313 "initial descriptors per channel (default: 64)");
314
315
316 static bool at_xdmac_chan_is_enabled(struct at_xdmac_chan *atchan)
317 {
318 return at_xdmac_chan_read(atchan, AT_XDMAC_GS) & atchan->mask;
319 }
320
321 static void at_xdmac_off(struct at_xdmac *atxdmac)
322 {
323 at_xdmac_write(atxdmac, AT_XDMAC_GD, -1L);
324
325 /* Wait that all chans are disabled. */
326 while (at_xdmac_read(atxdmac, AT_XDMAC_GS))
327 cpu_relax();
328
329 at_xdmac_write(atxdmac, AT_XDMAC_GID, -1L);
330 }
331
332 /* Call with lock hold. */
333 static void at_xdmac_start_xfer(struct at_xdmac_chan *atchan,
334 struct at_xdmac_desc *first)
335 {
336 struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
337 u32 reg;
338
339 dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, first);
340
341 if (at_xdmac_chan_is_enabled(atchan))
342 return;
343
344 /* Set transfer as active to not try to start it again. */
345 first->active_xfer = true;
346
347 /* Tell xdmac where to get the first descriptor. */
348 reg = AT_XDMAC_CNDA_NDA(first->tx_dma_desc.phys)
349 | AT_XDMAC_CNDA_NDAIF(atchan->memif);
350 at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, reg);
351
352 /*
353 * When doing non cyclic transfer we need to use the next
354 * descriptor view 2 since some fields of the configuration register
355 * depend on transfer size and src/dest addresses.
356 */
357 if (at_xdmac_chan_is_cyclic(atchan))
358 reg = AT_XDMAC_CNDC_NDVIEW_NDV1;
359 else if (first->lld.mbr_ubc & AT_XDMAC_MBR_UBC_NDV3)
360 reg = AT_XDMAC_CNDC_NDVIEW_NDV3;
361 else
362 reg = AT_XDMAC_CNDC_NDVIEW_NDV2;
363 /*
364 * Even if the register will be updated from the configuration in the
365 * descriptor when using view 2 or higher, the PROT bit won't be set
366 * properly. This bit can be modified only by using the channel
367 * configuration register.
368 */
369 at_xdmac_chan_write(atchan, AT_XDMAC_CC, first->lld.mbr_cfg);
370
371 reg |= AT_XDMAC_CNDC_NDDUP
372 | AT_XDMAC_CNDC_NDSUP
373 | AT_XDMAC_CNDC_NDE;
374 at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, reg);
375
376 dev_vdbg(chan2dev(&atchan->chan),
377 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
378 __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
379 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
380 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
381 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
382 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
383 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
384
385 at_xdmac_chan_write(atchan, AT_XDMAC_CID, 0xffffffff);
386 reg = AT_XDMAC_CIE_RBEIE | AT_XDMAC_CIE_WBEIE;
387 /*
388 * Request Overflow Error is only for peripheral synchronized transfers
389 */
390 if (at_xdmac_chan_is_peripheral_xfer(first->lld.mbr_cfg))
391 reg |= AT_XDMAC_CIE_ROIE;
392
393 /*
394 * There is no end of list when doing cyclic dma, we need to get
395 * an interrupt after each periods.
396 */
397 if (at_xdmac_chan_is_cyclic(atchan))
398 at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
399 reg | AT_XDMAC_CIE_BIE);
400 else
401 at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
402 reg | AT_XDMAC_CIE_LIE);
403 at_xdmac_write(atxdmac, AT_XDMAC_GIE, atchan->mask);
404 dev_vdbg(chan2dev(&atchan->chan),
405 "%s: enable channel (0x%08x)\n", __func__, atchan->mask);
406 wmb();
407 at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
408
409 dev_vdbg(chan2dev(&atchan->chan),
410 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
411 __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
412 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
413 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
414 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
415 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
416 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
417
418 }
419
420 static dma_cookie_t at_xdmac_tx_submit(struct dma_async_tx_descriptor *tx)
421 {
422 struct at_xdmac_desc *desc = txd_to_at_desc(tx);
423 struct at_xdmac_chan *atchan = to_at_xdmac_chan(tx->chan);
424 dma_cookie_t cookie;
425 unsigned long irqflags;
426
427 spin_lock_irqsave(&atchan->lock, irqflags);
428 cookie = dma_cookie_assign(tx);
429
430 dev_vdbg(chan2dev(tx->chan), "%s: atchan 0x%p, add desc 0x%p to xfers_list\n",
431 __func__, atchan, desc);
432 list_add_tail(&desc->xfer_node, &atchan->xfers_list);
433 if (list_is_singular(&atchan->xfers_list))
434 at_xdmac_start_xfer(atchan, desc);
435
436 spin_unlock_irqrestore(&atchan->lock, irqflags);
437 return cookie;
438 }
439
440 static struct at_xdmac_desc *at_xdmac_alloc_desc(struct dma_chan *chan,
441 gfp_t gfp_flags)
442 {
443 struct at_xdmac_desc *desc;
444 struct at_xdmac *atxdmac = to_at_xdmac(chan->device);
445 dma_addr_t phys;
446
447 desc = dma_pool_zalloc(atxdmac->at_xdmac_desc_pool, gfp_flags, &phys);
448 if (desc) {
449 INIT_LIST_HEAD(&desc->descs_list);
450 dma_async_tx_descriptor_init(&desc->tx_dma_desc, chan);
451 desc->tx_dma_desc.tx_submit = at_xdmac_tx_submit;
452 desc->tx_dma_desc.phys = phys;
453 }
454
455 return desc;
456 }
457
458 static void at_xdmac_init_used_desc(struct at_xdmac_desc *desc)
459 {
460 memset(&desc->lld, 0, sizeof(desc->lld));
461 INIT_LIST_HEAD(&desc->descs_list);
462 desc->direction = DMA_TRANS_NONE;
463 desc->xfer_size = 0;
464 desc->active_xfer = false;
465 }
466
467 /* Call must be protected by lock. */
468 static struct at_xdmac_desc *at_xdmac_get_desc(struct at_xdmac_chan *atchan)
469 {
470 struct at_xdmac_desc *desc;
471
472 if (list_empty(&atchan->free_descs_list)) {
473 desc = at_xdmac_alloc_desc(&atchan->chan, GFP_NOWAIT);
474 } else {
475 desc = list_first_entry(&atchan->free_descs_list,
476 struct at_xdmac_desc, desc_node);
477 list_del(&desc->desc_node);
478 at_xdmac_init_used_desc(desc);
479 }
480
481 return desc;
482 }
483
484 static void at_xdmac_queue_desc(struct dma_chan *chan,
485 struct at_xdmac_desc *prev,
486 struct at_xdmac_desc *desc)
487 {
488 if (!prev || !desc)
489 return;
490
491 prev->lld.mbr_nda = desc->tx_dma_desc.phys;
492 prev->lld.mbr_ubc |= AT_XDMAC_MBR_UBC_NDE;
493
494 dev_dbg(chan2dev(chan), "%s: chain lld: prev=0x%p, mbr_nda=%pad\n",
495 __func__, prev, &prev->lld.mbr_nda);
496 }
497
498 static inline void at_xdmac_increment_block_count(struct dma_chan *chan,
499 struct at_xdmac_desc *desc)
500 {
501 if (!desc)
502 return;
503
504 desc->lld.mbr_bc++;
505
506 dev_dbg(chan2dev(chan),
507 "%s: incrementing the block count of the desc 0x%p\n",
508 __func__, desc);
509 }
510
511 static struct dma_chan *at_xdmac_xlate(struct of_phandle_args *dma_spec,
512 struct of_dma *of_dma)
513 {
514 struct at_xdmac *atxdmac = of_dma->of_dma_data;
515 struct at_xdmac_chan *atchan;
516 struct dma_chan *chan;
517 struct device *dev = atxdmac->dma.dev;
518
519 if (dma_spec->args_count != 1) {
520 dev_err(dev, "dma phandler args: bad number of args\n");
521 return NULL;
522 }
523
524 chan = dma_get_any_slave_channel(&atxdmac->dma);
525 if (!chan) {
526 dev_err(dev, "can't get a dma channel\n");
527 return NULL;
528 }
529
530 atchan = to_at_xdmac_chan(chan);
531 atchan->memif = AT91_XDMAC_DT_GET_MEM_IF(dma_spec->args[0]);
532 atchan->perif = AT91_XDMAC_DT_GET_PER_IF(dma_spec->args[0]);
533 atchan->perid = AT91_XDMAC_DT_GET_PERID(dma_spec->args[0]);
534 dev_dbg(dev, "chan dt cfg: memif=%u perif=%u perid=%u\n",
535 atchan->memif, atchan->perif, atchan->perid);
536
537 return chan;
538 }
539
540 static int at_xdmac_compute_chan_conf(struct dma_chan *chan,
541 enum dma_transfer_direction direction)
542 {
543 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
544 int csize, dwidth;
545
546 if (direction == DMA_DEV_TO_MEM) {
547 atchan->cfg =
548 AT91_XDMAC_DT_PERID(atchan->perid)
549 | AT_XDMAC_CC_DAM_INCREMENTED_AM
550 | AT_XDMAC_CC_SAM_FIXED_AM
551 | AT_XDMAC_CC_DIF(atchan->memif)
552 | AT_XDMAC_CC_SIF(atchan->perif)
553 | AT_XDMAC_CC_SWREQ_HWR_CONNECTED
554 | AT_XDMAC_CC_DSYNC_PER2MEM
555 | AT_XDMAC_CC_MBSIZE_SIXTEEN
556 | AT_XDMAC_CC_TYPE_PER_TRAN;
557 csize = ffs(atchan->sconfig.src_maxburst) - 1;
558 if (csize < 0) {
559 dev_err(chan2dev(chan), "invalid src maxburst value\n");
560 return -EINVAL;
561 }
562 atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
563 dwidth = ffs(atchan->sconfig.src_addr_width) - 1;
564 if (dwidth < 0) {
565 dev_err(chan2dev(chan), "invalid src addr width value\n");
566 return -EINVAL;
567 }
568 atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
569 } else if (direction == DMA_MEM_TO_DEV) {
570 atchan->cfg =
571 AT91_XDMAC_DT_PERID(atchan->perid)
572 | AT_XDMAC_CC_DAM_FIXED_AM
573 | AT_XDMAC_CC_SAM_INCREMENTED_AM
574 | AT_XDMAC_CC_DIF(atchan->perif)
575 | AT_XDMAC_CC_SIF(atchan->memif)
576 | AT_XDMAC_CC_SWREQ_HWR_CONNECTED
577 | AT_XDMAC_CC_DSYNC_MEM2PER
578 | AT_XDMAC_CC_MBSIZE_SIXTEEN
579 | AT_XDMAC_CC_TYPE_PER_TRAN;
580 csize = ffs(atchan->sconfig.dst_maxburst) - 1;
581 if (csize < 0) {
582 dev_err(chan2dev(chan), "invalid src maxburst value\n");
583 return -EINVAL;
584 }
585 atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
586 dwidth = ffs(atchan->sconfig.dst_addr_width) - 1;
587 if (dwidth < 0) {
588 dev_err(chan2dev(chan), "invalid dst addr width value\n");
589 return -EINVAL;
590 }
591 atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
592 }
593
594 dev_dbg(chan2dev(chan), "%s: cfg=0x%08x\n", __func__, atchan->cfg);
595
596 return 0;
597 }
598
599 /*
600 * Only check that maxburst and addr width values are supported by the
601 * the controller but not that the configuration is good to perform the
602 * transfer since we don't know the direction at this stage.
603 */
604 static int at_xdmac_check_slave_config(struct dma_slave_config *sconfig)
605 {
606 if ((sconfig->src_maxburst > AT_XDMAC_MAX_CSIZE)
607 || (sconfig->dst_maxburst > AT_XDMAC_MAX_CSIZE))
608 return -EINVAL;
609
610 if ((sconfig->src_addr_width > AT_XDMAC_MAX_DWIDTH)
611 || (sconfig->dst_addr_width > AT_XDMAC_MAX_DWIDTH))
612 return -EINVAL;
613
614 return 0;
615 }
616
617 static int at_xdmac_set_slave_config(struct dma_chan *chan,
618 struct dma_slave_config *sconfig)
619 {
620 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
621
622 if (at_xdmac_check_slave_config(sconfig)) {
623 dev_err(chan2dev(chan), "invalid slave configuration\n");
624 return -EINVAL;
625 }
626
627 memcpy(&atchan->sconfig, sconfig, sizeof(atchan->sconfig));
628
629 return 0;
630 }
631
632 static struct dma_async_tx_descriptor *
633 at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
634 unsigned int sg_len, enum dma_transfer_direction direction,
635 unsigned long flags, void *context)
636 {
637 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
638 struct at_xdmac_desc *first = NULL, *prev = NULL;
639 struct scatterlist *sg;
640 int i;
641 unsigned int xfer_size = 0;
642 unsigned long irqflags;
643 struct dma_async_tx_descriptor *ret = NULL;
644
645 if (!sgl)
646 return NULL;
647
648 if (!is_slave_direction(direction)) {
649 dev_err(chan2dev(chan), "invalid DMA direction\n");
650 return NULL;
651 }
652
653 dev_dbg(chan2dev(chan), "%s: sg_len=%d, dir=%s, flags=0x%lx\n",
654 __func__, sg_len,
655 direction == DMA_MEM_TO_DEV ? "to device" : "from device",
656 flags);
657
658 /* Protect dma_sconfig field that can be modified by set_slave_conf. */
659 spin_lock_irqsave(&atchan->lock, irqflags);
660
661 if (at_xdmac_compute_chan_conf(chan, direction))
662 goto spin_unlock;
663
664 /* Prepare descriptors. */
665 for_each_sg(sgl, sg, sg_len, i) {
666 struct at_xdmac_desc *desc = NULL;
667 u32 len, mem, dwidth, fixed_dwidth;
668
669 len = sg_dma_len(sg);
670 mem = sg_dma_address(sg);
671 if (unlikely(!len)) {
672 dev_err(chan2dev(chan), "sg data length is zero\n");
673 goto spin_unlock;
674 }
675 dev_dbg(chan2dev(chan), "%s: * sg%d len=%u, mem=0x%08x\n",
676 __func__, i, len, mem);
677
678 desc = at_xdmac_get_desc(atchan);
679 if (!desc) {
680 dev_err(chan2dev(chan), "can't get descriptor\n");
681 if (first)
682 list_splice_init(&first->descs_list, &atchan->free_descs_list);
683 goto spin_unlock;
684 }
685
686 /* Linked list descriptor setup. */
687 if (direction == DMA_DEV_TO_MEM) {
688 desc->lld.mbr_sa = atchan->sconfig.src_addr;
689 desc->lld.mbr_da = mem;
690 } else {
691 desc->lld.mbr_sa = mem;
692 desc->lld.mbr_da = atchan->sconfig.dst_addr;
693 }
694 dwidth = at_xdmac_get_dwidth(atchan->cfg);
695 fixed_dwidth = IS_ALIGNED(len, 1 << dwidth)
696 ? dwidth
697 : AT_XDMAC_CC_DWIDTH_BYTE;
698 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2 /* next descriptor view */
699 | AT_XDMAC_MBR_UBC_NDEN /* next descriptor dst parameter update */
700 | AT_XDMAC_MBR_UBC_NSEN /* next descriptor src parameter update */
701 | (len >> fixed_dwidth); /* microblock length */
702 desc->lld.mbr_cfg = (atchan->cfg & ~AT_XDMAC_CC_DWIDTH_MASK) |
703 AT_XDMAC_CC_DWIDTH(fixed_dwidth);
704 dev_dbg(chan2dev(chan),
705 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
706 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
707
708 /* Chain lld. */
709 if (prev)
710 at_xdmac_queue_desc(chan, prev, desc);
711
712 prev = desc;
713 if (!first)
714 first = desc;
715
716 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
717 __func__, desc, first);
718 list_add_tail(&desc->desc_node, &first->descs_list);
719 xfer_size += len;
720 }
721
722
723 first->tx_dma_desc.flags = flags;
724 first->xfer_size = xfer_size;
725 first->direction = direction;
726 ret = &first->tx_dma_desc;
727
728 spin_unlock:
729 spin_unlock_irqrestore(&atchan->lock, irqflags);
730 return ret;
731 }
732
733 static struct dma_async_tx_descriptor *
734 at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr,
735 size_t buf_len, size_t period_len,
736 enum dma_transfer_direction direction,
737 unsigned long flags)
738 {
739 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
740 struct at_xdmac_desc *first = NULL, *prev = NULL;
741 unsigned int periods = buf_len / period_len;
742 int i;
743 unsigned long irqflags;
744
745 dev_dbg(chan2dev(chan), "%s: buf_addr=%pad, buf_len=%zd, period_len=%zd, dir=%s, flags=0x%lx\n",
746 __func__, &buf_addr, buf_len, period_len,
747 direction == DMA_MEM_TO_DEV ? "mem2per" : "per2mem", flags);
748
749 if (!is_slave_direction(direction)) {
750 dev_err(chan2dev(chan), "invalid DMA direction\n");
751 return NULL;
752 }
753
754 if (test_and_set_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status)) {
755 dev_err(chan2dev(chan), "channel currently used\n");
756 return NULL;
757 }
758
759 if (at_xdmac_compute_chan_conf(chan, direction))
760 return NULL;
761
762 for (i = 0; i < periods; i++) {
763 struct at_xdmac_desc *desc = NULL;
764
765 spin_lock_irqsave(&atchan->lock, irqflags);
766 desc = at_xdmac_get_desc(atchan);
767 if (!desc) {
768 dev_err(chan2dev(chan), "can't get descriptor\n");
769 if (first)
770 list_splice_init(&first->descs_list, &atchan->free_descs_list);
771 spin_unlock_irqrestore(&atchan->lock, irqflags);
772 return NULL;
773 }
774 spin_unlock_irqrestore(&atchan->lock, irqflags);
775 dev_dbg(chan2dev(chan),
776 "%s: desc=0x%p, tx_dma_desc.phys=%pad\n",
777 __func__, desc, &desc->tx_dma_desc.phys);
778
779 if (direction == DMA_DEV_TO_MEM) {
780 desc->lld.mbr_sa = atchan->sconfig.src_addr;
781 desc->lld.mbr_da = buf_addr + i * period_len;
782 } else {
783 desc->lld.mbr_sa = buf_addr + i * period_len;
784 desc->lld.mbr_da = atchan->sconfig.dst_addr;
785 }
786 desc->lld.mbr_cfg = atchan->cfg;
787 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV1
788 | AT_XDMAC_MBR_UBC_NDEN
789 | AT_XDMAC_MBR_UBC_NSEN
790 | period_len >> at_xdmac_get_dwidth(desc->lld.mbr_cfg);
791
792 dev_dbg(chan2dev(chan),
793 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
794 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
795
796 /* Chain lld. */
797 if (prev)
798 at_xdmac_queue_desc(chan, prev, desc);
799
800 prev = desc;
801 if (!first)
802 first = desc;
803
804 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
805 __func__, desc, first);
806 list_add_tail(&desc->desc_node, &first->descs_list);
807 }
808
809 at_xdmac_queue_desc(chan, prev, first);
810 first->tx_dma_desc.flags = flags;
811 first->xfer_size = buf_len;
812 first->direction = direction;
813
814 return &first->tx_dma_desc;
815 }
816
817 static inline u32 at_xdmac_align_width(struct dma_chan *chan, dma_addr_t addr)
818 {
819 u32 width;
820
821 /*
822 * Check address alignment to select the greater data width we
823 * can use.
824 *
825 * Some XDMAC implementations don't provide dword transfer, in
826 * this case selecting dword has the same behavior as
827 * selecting word transfers.
828 */
829 if (!(addr & 7)) {
830 width = AT_XDMAC_CC_DWIDTH_DWORD;
831 dev_dbg(chan2dev(chan), "%s: dwidth: double word\n", __func__);
832 } else if (!(addr & 3)) {
833 width = AT_XDMAC_CC_DWIDTH_WORD;
834 dev_dbg(chan2dev(chan), "%s: dwidth: word\n", __func__);
835 } else if (!(addr & 1)) {
836 width = AT_XDMAC_CC_DWIDTH_HALFWORD;
837 dev_dbg(chan2dev(chan), "%s: dwidth: half word\n", __func__);
838 } else {
839 width = AT_XDMAC_CC_DWIDTH_BYTE;
840 dev_dbg(chan2dev(chan), "%s: dwidth: byte\n", __func__);
841 }
842
843 return width;
844 }
845
846 static struct at_xdmac_desc *
847 at_xdmac_interleaved_queue_desc(struct dma_chan *chan,
848 struct at_xdmac_chan *atchan,
849 struct at_xdmac_desc *prev,
850 dma_addr_t src, dma_addr_t dst,
851 struct dma_interleaved_template *xt,
852 struct data_chunk *chunk)
853 {
854 struct at_xdmac_desc *desc;
855 u32 dwidth;
856 unsigned long flags;
857 size_t ublen;
858 /*
859 * WARNING: The channel configuration is set here since there is no
860 * dmaengine_slave_config call in this case. Moreover we don't know the
861 * direction, it involves we can't dynamically set the source and dest
862 * interface so we have to use the same one. Only interface 0 allows EBI
863 * access. Hopefully we can access DDR through both ports (at least on
864 * SAMA5D4x), so we can use the same interface for source and dest,
865 * that solves the fact we don't know the direction.
866 * ERRATA: Even if useless for memory transfers, the PERID has to not
867 * match the one of another channel. If not, it could lead to spurious
868 * flag status.
869 */
870 u32 chan_cc = AT_XDMAC_CC_PERID(0x3f)
871 | AT_XDMAC_CC_DIF(0)
872 | AT_XDMAC_CC_SIF(0)
873 | AT_XDMAC_CC_MBSIZE_SIXTEEN
874 | AT_XDMAC_CC_TYPE_MEM_TRAN;
875
876 dwidth = at_xdmac_align_width(chan, src | dst | chunk->size);
877 if (chunk->size >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
878 dev_dbg(chan2dev(chan),
879 "%s: chunk too big (%zu, max size %lu)...\n",
880 __func__, chunk->size,
881 AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth);
882 return NULL;
883 }
884
885 if (prev)
886 dev_dbg(chan2dev(chan),
887 "Adding items at the end of desc 0x%p\n", prev);
888
889 if (xt->src_inc) {
890 if (xt->src_sgl)
891 chan_cc |= AT_XDMAC_CC_SAM_UBS_AM;
892 else
893 chan_cc |= AT_XDMAC_CC_SAM_INCREMENTED_AM;
894 }
895
896 if (xt->dst_inc) {
897 if (xt->dst_sgl)
898 chan_cc |= AT_XDMAC_CC_DAM_UBS_AM;
899 else
900 chan_cc |= AT_XDMAC_CC_DAM_INCREMENTED_AM;
901 }
902
903 spin_lock_irqsave(&atchan->lock, flags);
904 desc = at_xdmac_get_desc(atchan);
905 spin_unlock_irqrestore(&atchan->lock, flags);
906 if (!desc) {
907 dev_err(chan2dev(chan), "can't get descriptor\n");
908 return NULL;
909 }
910
911 chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
912
913 ublen = chunk->size >> dwidth;
914
915 desc->lld.mbr_sa = src;
916 desc->lld.mbr_da = dst;
917 desc->lld.mbr_sus = dmaengine_get_src_icg(xt, chunk);
918 desc->lld.mbr_dus = dmaengine_get_dst_icg(xt, chunk);
919
920 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
921 | AT_XDMAC_MBR_UBC_NDEN
922 | AT_XDMAC_MBR_UBC_NSEN
923 | ublen;
924 desc->lld.mbr_cfg = chan_cc;
925
926 dev_dbg(chan2dev(chan),
927 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
928 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da,
929 desc->lld.mbr_ubc, desc->lld.mbr_cfg);
930
931 /* Chain lld. */
932 if (prev)
933 at_xdmac_queue_desc(chan, prev, desc);
934
935 return desc;
936 }
937
938 static struct dma_async_tx_descriptor *
939 at_xdmac_prep_interleaved(struct dma_chan *chan,
940 struct dma_interleaved_template *xt,
941 unsigned long flags)
942 {
943 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
944 struct at_xdmac_desc *prev = NULL, *first = NULL;
945 dma_addr_t dst_addr, src_addr;
946 size_t src_skip = 0, dst_skip = 0, len = 0;
947 struct data_chunk *chunk;
948 int i;
949
950 if (!xt || !xt->numf || (xt->dir != DMA_MEM_TO_MEM))
951 return NULL;
952
953 /*
954 * TODO: Handle the case where we have to repeat a chain of
955 * descriptors...
956 */
957 if ((xt->numf > 1) && (xt->frame_size > 1))
958 return NULL;
959
960 dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, numf=%zu, frame_size=%zu, flags=0x%lx\n",
961 __func__, &xt->src_start, &xt->dst_start, xt->numf,
962 xt->frame_size, flags);
963
964 src_addr = xt->src_start;
965 dst_addr = xt->dst_start;
966
967 if (xt->numf > 1) {
968 first = at_xdmac_interleaved_queue_desc(chan, atchan,
969 NULL,
970 src_addr, dst_addr,
971 xt, xt->sgl);
972
973 /* Length of the block is (BLEN+1) microblocks. */
974 for (i = 0; i < xt->numf - 1; i++)
975 at_xdmac_increment_block_count(chan, first);
976
977 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
978 __func__, first, first);
979 list_add_tail(&first->desc_node, &first->descs_list);
980 } else {
981 for (i = 0; i < xt->frame_size; i++) {
982 size_t src_icg = 0, dst_icg = 0;
983 struct at_xdmac_desc *desc;
984
985 chunk = xt->sgl + i;
986
987 dst_icg = dmaengine_get_dst_icg(xt, chunk);
988 src_icg = dmaengine_get_src_icg(xt, chunk);
989
990 src_skip = chunk->size + src_icg;
991 dst_skip = chunk->size + dst_icg;
992
993 dev_dbg(chan2dev(chan),
994 "%s: chunk size=%zu, src icg=%zu, dst icg=%zu\n",
995 __func__, chunk->size, src_icg, dst_icg);
996
997 desc = at_xdmac_interleaved_queue_desc(chan, atchan,
998 prev,
999 src_addr, dst_addr,
1000 xt, chunk);
1001 if (!desc) {
1002 list_splice_init(&first->descs_list,
1003 &atchan->free_descs_list);
1004 return NULL;
1005 }
1006
1007 if (!first)
1008 first = desc;
1009
1010 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1011 __func__, desc, first);
1012 list_add_tail(&desc->desc_node, &first->descs_list);
1013
1014 if (xt->src_sgl)
1015 src_addr += src_skip;
1016
1017 if (xt->dst_sgl)
1018 dst_addr += dst_skip;
1019
1020 len += chunk->size;
1021 prev = desc;
1022 }
1023 }
1024
1025 first->tx_dma_desc.cookie = -EBUSY;
1026 first->tx_dma_desc.flags = flags;
1027 first->xfer_size = len;
1028
1029 return &first->tx_dma_desc;
1030 }
1031
1032 static struct dma_async_tx_descriptor *
1033 at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
1034 size_t len, unsigned long flags)
1035 {
1036 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1037 struct at_xdmac_desc *first = NULL, *prev = NULL;
1038 size_t remaining_size = len, xfer_size = 0, ublen;
1039 dma_addr_t src_addr = src, dst_addr = dest;
1040 u32 dwidth;
1041 /*
1042 * WARNING: We don't know the direction, it involves we can't
1043 * dynamically set the source and dest interface so we have to use the
1044 * same one. Only interface 0 allows EBI access. Hopefully we can
1045 * access DDR through both ports (at least on SAMA5D4x), so we can use
1046 * the same interface for source and dest, that solves the fact we
1047 * don't know the direction.
1048 * ERRATA: Even if useless for memory transfers, the PERID has to not
1049 * match the one of another channel. If not, it could lead to spurious
1050 * flag status.
1051 */
1052 u32 chan_cc = AT_XDMAC_CC_PERID(0x3f)
1053 | AT_XDMAC_CC_DAM_INCREMENTED_AM
1054 | AT_XDMAC_CC_SAM_INCREMENTED_AM
1055 | AT_XDMAC_CC_DIF(0)
1056 | AT_XDMAC_CC_SIF(0)
1057 | AT_XDMAC_CC_MBSIZE_SIXTEEN
1058 | AT_XDMAC_CC_TYPE_MEM_TRAN;
1059 unsigned long irqflags;
1060
1061 dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, len=%zd, flags=0x%lx\n",
1062 __func__, &src, &dest, len, flags);
1063
1064 if (unlikely(!len))
1065 return NULL;
1066
1067 dwidth = at_xdmac_align_width(chan, src_addr | dst_addr);
1068
1069 /* Prepare descriptors. */
1070 while (remaining_size) {
1071 struct at_xdmac_desc *desc = NULL;
1072
1073 dev_dbg(chan2dev(chan), "%s: remaining_size=%zu\n", __func__, remaining_size);
1074
1075 spin_lock_irqsave(&atchan->lock, irqflags);
1076 desc = at_xdmac_get_desc(atchan);
1077 spin_unlock_irqrestore(&atchan->lock, irqflags);
1078 if (!desc) {
1079 dev_err(chan2dev(chan), "can't get descriptor\n");
1080 if (first)
1081 list_splice_init(&first->descs_list, &atchan->free_descs_list);
1082 return NULL;
1083 }
1084
1085 /* Update src and dest addresses. */
1086 src_addr += xfer_size;
1087 dst_addr += xfer_size;
1088
1089 if (remaining_size >= AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)
1090 xfer_size = AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth;
1091 else
1092 xfer_size = remaining_size;
1093
1094 dev_dbg(chan2dev(chan), "%s: xfer_size=%zu\n", __func__, xfer_size);
1095
1096 /* Check remaining length and change data width if needed. */
1097 dwidth = at_xdmac_align_width(chan,
1098 src_addr | dst_addr | xfer_size);
1099 chan_cc &= ~AT_XDMAC_CC_DWIDTH_MASK;
1100 chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1101
1102 ublen = xfer_size >> dwidth;
1103 remaining_size -= xfer_size;
1104
1105 desc->lld.mbr_sa = src_addr;
1106 desc->lld.mbr_da = dst_addr;
1107 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2
1108 | AT_XDMAC_MBR_UBC_NDEN
1109 | AT_XDMAC_MBR_UBC_NSEN
1110 | ublen;
1111 desc->lld.mbr_cfg = chan_cc;
1112
1113 dev_dbg(chan2dev(chan),
1114 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1115 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc, desc->lld.mbr_cfg);
1116
1117 /* Chain lld. */
1118 if (prev)
1119 at_xdmac_queue_desc(chan, prev, desc);
1120
1121 prev = desc;
1122 if (!first)
1123 first = desc;
1124
1125 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1126 __func__, desc, first);
1127 list_add_tail(&desc->desc_node, &first->descs_list);
1128 }
1129
1130 first->tx_dma_desc.flags = flags;
1131 first->xfer_size = len;
1132
1133 return &first->tx_dma_desc;
1134 }
1135
1136 static struct at_xdmac_desc *at_xdmac_memset_create_desc(struct dma_chan *chan,
1137 struct at_xdmac_chan *atchan,
1138 dma_addr_t dst_addr,
1139 size_t len,
1140 int value)
1141 {
1142 struct at_xdmac_desc *desc;
1143 unsigned long flags;
1144 size_t ublen;
1145 u32 dwidth;
1146 /*
1147 * WARNING: The channel configuration is set here since there is no
1148 * dmaengine_slave_config call in this case. Moreover we don't know the
1149 * direction, it involves we can't dynamically set the source and dest
1150 * interface so we have to use the same one. Only interface 0 allows EBI
1151 * access. Hopefully we can access DDR through both ports (at least on
1152 * SAMA5D4x), so we can use the same interface for source and dest,
1153 * that solves the fact we don't know the direction.
1154 * ERRATA: Even if useless for memory transfers, the PERID has to not
1155 * match the one of another channel. If not, it could lead to spurious
1156 * flag status.
1157 */
1158 u32 chan_cc = AT_XDMAC_CC_PERID(0x3f)
1159 | AT_XDMAC_CC_DAM_UBS_AM
1160 | AT_XDMAC_CC_SAM_INCREMENTED_AM
1161 | AT_XDMAC_CC_DIF(0)
1162 | AT_XDMAC_CC_SIF(0)
1163 | AT_XDMAC_CC_MBSIZE_SIXTEEN
1164 | AT_XDMAC_CC_MEMSET_HW_MODE
1165 | AT_XDMAC_CC_TYPE_MEM_TRAN;
1166
1167 dwidth = at_xdmac_align_width(chan, dst_addr);
1168
1169 if (len >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
1170 dev_err(chan2dev(chan),
1171 "%s: Transfer too large, aborting...\n",
1172 __func__);
1173 return NULL;
1174 }
1175
1176 spin_lock_irqsave(&atchan->lock, flags);
1177 desc = at_xdmac_get_desc(atchan);
1178 spin_unlock_irqrestore(&atchan->lock, flags);
1179 if (!desc) {
1180 dev_err(chan2dev(chan), "can't get descriptor\n");
1181 return NULL;
1182 }
1183
1184 chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1185
1186 ublen = len >> dwidth;
1187
1188 desc->lld.mbr_da = dst_addr;
1189 desc->lld.mbr_ds = value;
1190 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
1191 | AT_XDMAC_MBR_UBC_NDEN
1192 | AT_XDMAC_MBR_UBC_NSEN
1193 | ublen;
1194 desc->lld.mbr_cfg = chan_cc;
1195
1196 dev_dbg(chan2dev(chan),
1197 "%s: lld: mbr_da=%pad, mbr_ds=0x%08x, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1198 __func__, &desc->lld.mbr_da, desc->lld.mbr_ds, desc->lld.mbr_ubc,
1199 desc->lld.mbr_cfg);
1200
1201 return desc;
1202 }
1203
1204 static struct dma_async_tx_descriptor *
1205 at_xdmac_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value,
1206 size_t len, unsigned long flags)
1207 {
1208 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1209 struct at_xdmac_desc *desc;
1210
1211 dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%zu, pattern=0x%x, flags=0x%lx\n",
1212 __func__, &dest, len, value, flags);
1213
1214 if (unlikely(!len))
1215 return NULL;
1216
1217 desc = at_xdmac_memset_create_desc(chan, atchan, dest, len, value);
1218 list_add_tail(&desc->desc_node, &desc->descs_list);
1219
1220 desc->tx_dma_desc.cookie = -EBUSY;
1221 desc->tx_dma_desc.flags = flags;
1222 desc->xfer_size = len;
1223
1224 return &desc->tx_dma_desc;
1225 }
1226
1227 static struct dma_async_tx_descriptor *
1228 at_xdmac_prep_dma_memset_sg(struct dma_chan *chan, struct scatterlist *sgl,
1229 unsigned int sg_len, int value,
1230 unsigned long flags)
1231 {
1232 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1233 struct at_xdmac_desc *desc, *pdesc = NULL,
1234 *ppdesc = NULL, *first = NULL;
1235 struct scatterlist *sg, *psg = NULL, *ppsg = NULL;
1236 size_t stride = 0, pstride = 0, len = 0;
1237 int i;
1238
1239 if (!sgl)
1240 return NULL;
1241
1242 dev_dbg(chan2dev(chan), "%s: sg_len=%d, value=0x%x, flags=0x%lx\n",
1243 __func__, sg_len, value, flags);
1244
1245 /* Prepare descriptors. */
1246 for_each_sg(sgl, sg, sg_len, i) {
1247 dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%d, pattern=0x%x, flags=0x%lx\n",
1248 __func__, &sg_dma_address(sg), sg_dma_len(sg),
1249 value, flags);
1250 desc = at_xdmac_memset_create_desc(chan, atchan,
1251 sg_dma_address(sg),
1252 sg_dma_len(sg),
1253 value);
1254 if (!desc && first)
1255 list_splice_init(&first->descs_list,
1256 &atchan->free_descs_list);
1257
1258 if (!first)
1259 first = desc;
1260
1261 /* Update our strides */
1262 pstride = stride;
1263 if (psg)
1264 stride = sg_dma_address(sg) -
1265 (sg_dma_address(psg) + sg_dma_len(psg));
1266
1267 /*
1268 * The scatterlist API gives us only the address and
1269 * length of each elements.
1270 *
1271 * Unfortunately, we don't have the stride, which we
1272 * will need to compute.
1273 *
1274 * That make us end up in a situation like this one:
1275 * len stride len stride len
1276 * +-------+ +-------+ +-------+
1277 * | N-2 | | N-1 | | N |
1278 * +-------+ +-------+ +-------+
1279 *
1280 * We need all these three elements (N-2, N-1 and N)
1281 * to actually take the decision on whether we need to
1282 * queue N-1 or reuse N-2.
1283 *
1284 * We will only consider N if it is the last element.
1285 */
1286 if (ppdesc && pdesc) {
1287 if ((stride == pstride) &&
1288 (sg_dma_len(ppsg) == sg_dma_len(psg))) {
1289 dev_dbg(chan2dev(chan),
1290 "%s: desc 0x%p can be merged with desc 0x%p\n",
1291 __func__, pdesc, ppdesc);
1292
1293 /*
1294 * Increment the block count of the
1295 * N-2 descriptor
1296 */
1297 at_xdmac_increment_block_count(chan, ppdesc);
1298 ppdesc->lld.mbr_dus = stride;
1299
1300 /*
1301 * Put back the N-1 descriptor in the
1302 * free descriptor list
1303 */
1304 list_add_tail(&pdesc->desc_node,
1305 &atchan->free_descs_list);
1306
1307 /*
1308 * Make our N-1 descriptor pointer
1309 * point to the N-2 since they were
1310 * actually merged.
1311 */
1312 pdesc = ppdesc;
1313
1314 /*
1315 * Rule out the case where we don't have
1316 * pstride computed yet (our second sg
1317 * element)
1318 *
1319 * We also want to catch the case where there
1320 * would be a negative stride,
1321 */
1322 } else if (pstride ||
1323 sg_dma_address(sg) < sg_dma_address(psg)) {
1324 /*
1325 * Queue the N-1 descriptor after the
1326 * N-2
1327 */
1328 at_xdmac_queue_desc(chan, ppdesc, pdesc);
1329
1330 /*
1331 * Add the N-1 descriptor to the list
1332 * of the descriptors used for this
1333 * transfer
1334 */
1335 list_add_tail(&desc->desc_node,
1336 &first->descs_list);
1337 dev_dbg(chan2dev(chan),
1338 "%s: add desc 0x%p to descs_list 0x%p\n",
1339 __func__, desc, first);
1340 }
1341 }
1342
1343 /*
1344 * If we are the last element, just see if we have the
1345 * same size than the previous element.
1346 *
1347 * If so, we can merge it with the previous descriptor
1348 * since we don't care about the stride anymore.
1349 */
1350 if ((i == (sg_len - 1)) &&
1351 sg_dma_len(psg) == sg_dma_len(sg)) {
1352 dev_dbg(chan2dev(chan),
1353 "%s: desc 0x%p can be merged with desc 0x%p\n",
1354 __func__, desc, pdesc);
1355
1356 /*
1357 * Increment the block count of the N-1
1358 * descriptor
1359 */
1360 at_xdmac_increment_block_count(chan, pdesc);
1361 pdesc->lld.mbr_dus = stride;
1362
1363 /*
1364 * Put back the N descriptor in the free
1365 * descriptor list
1366 */
1367 list_add_tail(&desc->desc_node,
1368 &atchan->free_descs_list);
1369 }
1370
1371 /* Update our descriptors */
1372 ppdesc = pdesc;
1373 pdesc = desc;
1374
1375 /* Update our scatter pointers */
1376 ppsg = psg;
1377 psg = sg;
1378
1379 len += sg_dma_len(sg);
1380 }
1381
1382 first->tx_dma_desc.cookie = -EBUSY;
1383 first->tx_dma_desc.flags = flags;
1384 first->xfer_size = len;
1385
1386 return &first->tx_dma_desc;
1387 }
1388
1389 static enum dma_status
1390 at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
1391 struct dma_tx_state *txstate)
1392 {
1393 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1394 struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
1395 struct at_xdmac_desc *desc, *_desc;
1396 struct list_head *descs_list;
1397 enum dma_status ret;
1398 int residue, retry;
1399 u32 cur_nda, check_nda, cur_ubc, mask, value;
1400 u8 dwidth = 0;
1401 unsigned long flags;
1402 bool initd;
1403
1404 ret = dma_cookie_status(chan, cookie, txstate);
1405 if (ret == DMA_COMPLETE)
1406 return ret;
1407
1408 if (!txstate)
1409 return ret;
1410
1411 spin_lock_irqsave(&atchan->lock, flags);
1412
1413 desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node);
1414
1415 /*
1416 * If the transfer has not been started yet, don't need to compute the
1417 * residue, it's the transfer length.
1418 */
1419 if (!desc->active_xfer) {
1420 dma_set_residue(txstate, desc->xfer_size);
1421 goto spin_unlock;
1422 }
1423
1424 residue = desc->xfer_size;
1425 /*
1426 * Flush FIFO: only relevant when the transfer is source peripheral
1427 * synchronized. Flush is needed before reading CUBC because data in
1428 * the FIFO are not reported by CUBC. Reporting a residue of the
1429 * transfer length while we have data in FIFO can cause issue.
1430 * Usecase: atmel USART has a timeout which means I have received
1431 * characters but there is no more character received for a while. On
1432 * timeout, it requests the residue. If the data are in the DMA FIFO,
1433 * we will return a residue of the transfer length. It means no data
1434 * received. If an application is waiting for these data, it will hang
1435 * since we won't have another USART timeout without receiving new
1436 * data.
1437 */
1438 mask = AT_XDMAC_CC_TYPE | AT_XDMAC_CC_DSYNC;
1439 value = AT_XDMAC_CC_TYPE_PER_TRAN | AT_XDMAC_CC_DSYNC_PER2MEM;
1440 if ((desc->lld.mbr_cfg & mask) == value) {
1441 at_xdmac_write(atxdmac, AT_XDMAC_GSWF, atchan->mask);
1442 while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS))
1443 cpu_relax();
1444 }
1445
1446 /*
1447 * The easiest way to compute the residue should be to pause the DMA
1448 * but doing this can lead to miss some data as some devices don't
1449 * have FIFO.
1450 * We need to read several registers because:
1451 * - DMA is running therefore a descriptor change is possible while
1452 * reading these registers
1453 * - When the block transfer is done, the value of the CUBC register
1454 * is set to its initial value until the fetch of the next descriptor.
1455 * This value will corrupt the residue calculation so we have to skip
1456 * it.
1457 *
1458 * INITD -------- ------------
1459 * |____________________|
1460 * _______________________ _______________
1461 * NDA @desc2 \/ @desc3
1462 * _______________________/\_______________
1463 * __________ ___________ _______________
1464 * CUBC 0 \/ MAX desc1 \/ MAX desc2
1465 * __________/\___________/\_______________
1466 *
1467 * Since descriptors are aligned on 64 bits, we can assume that
1468 * the update of NDA and CUBC is atomic.
1469 * Memory barriers are used to ensure the read order of the registers.
1470 * A max number of retries is set because unlikely it could never ends.
1471 */
1472 for (retry = 0; retry < AT_XDMAC_RESIDUE_MAX_RETRIES; retry++) {
1473 check_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
1474 rmb();
1475 cur_ubc = at_xdmac_chan_read(atchan, AT_XDMAC_CUBC);
1476 rmb();
1477 initd = !!(at_xdmac_chan_read(atchan, AT_XDMAC_CC) & AT_XDMAC_CC_INITD);
1478 rmb();
1479 cur_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
1480 rmb();
1481
1482 if ((check_nda == cur_nda) && initd)
1483 break;
1484 }
1485
1486 if (unlikely(retry >= AT_XDMAC_RESIDUE_MAX_RETRIES)) {
1487 ret = DMA_ERROR;
1488 goto spin_unlock;
1489 }
1490
1491 /*
1492 * Flush FIFO: only relevant when the transfer is source peripheral
1493 * synchronized. Another flush is needed here because CUBC is updated
1494 * when the controller sends the data write command. It can lead to
1495 * report data that are not written in the memory or the device. The
1496 * FIFO flush ensures that data are really written.
1497 */
1498 if ((desc->lld.mbr_cfg & mask) == value) {
1499 at_xdmac_write(atxdmac, AT_XDMAC_GSWF, atchan->mask);
1500 while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS))
1501 cpu_relax();
1502 }
1503
1504 /*
1505 * Remove size of all microblocks already transferred and the current
1506 * one. Then add the remaining size to transfer of the current
1507 * microblock.
1508 */
1509 descs_list = &desc->descs_list;
1510 list_for_each_entry_safe(desc, _desc, descs_list, desc_node) {
1511 dwidth = at_xdmac_get_dwidth(desc->lld.mbr_cfg);
1512 residue -= (desc->lld.mbr_ubc & 0xffffff) << dwidth;
1513 if ((desc->lld.mbr_nda & 0xfffffffc) == cur_nda)
1514 break;
1515 }
1516 residue += cur_ubc << dwidth;
1517
1518 dma_set_residue(txstate, residue);
1519
1520 dev_dbg(chan2dev(chan),
1521 "%s: desc=0x%p, tx_dma_desc.phys=%pad, tx_status=%d, cookie=%d, residue=%d\n",
1522 __func__, desc, &desc->tx_dma_desc.phys, ret, cookie, residue);
1523
1524 spin_unlock:
1525 spin_unlock_irqrestore(&atchan->lock, flags);
1526 return ret;
1527 }
1528
1529 /* Call must be protected by lock. */
1530 static void at_xdmac_remove_xfer(struct at_xdmac_chan *atchan,
1531 struct at_xdmac_desc *desc)
1532 {
1533 dev_dbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1534
1535 /*
1536 * Remove the transfer from the transfer list then move the transfer
1537 * descriptors into the free descriptors list.
1538 */
1539 list_del(&desc->xfer_node);
1540 list_splice_init(&desc->descs_list, &atchan->free_descs_list);
1541 }
1542
1543 static void at_xdmac_advance_work(struct at_xdmac_chan *atchan)
1544 {
1545 struct at_xdmac_desc *desc;
1546 unsigned long flags;
1547
1548 spin_lock_irqsave(&atchan->lock, flags);
1549
1550 /*
1551 * If channel is enabled, do nothing, advance_work will be triggered
1552 * after the interruption.
1553 */
1554 if (!at_xdmac_chan_is_enabled(atchan) && !list_empty(&atchan->xfers_list)) {
1555 desc = list_first_entry(&atchan->xfers_list,
1556 struct at_xdmac_desc,
1557 xfer_node);
1558 dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1559 if (!desc->active_xfer)
1560 at_xdmac_start_xfer(atchan, desc);
1561 }
1562
1563 spin_unlock_irqrestore(&atchan->lock, flags);
1564 }
1565
1566 static void at_xdmac_handle_cyclic(struct at_xdmac_chan *atchan)
1567 {
1568 struct at_xdmac_desc *desc;
1569 struct dma_async_tx_descriptor *txd;
1570
1571 if (!list_empty(&atchan->xfers_list)) {
1572 desc = list_first_entry(&atchan->xfers_list,
1573 struct at_xdmac_desc, xfer_node);
1574 txd = &desc->tx_dma_desc;
1575
1576 if (txd->flags & DMA_PREP_INTERRUPT)
1577 dmaengine_desc_get_callback_invoke(txd, NULL);
1578 }
1579 }
1580
1581 static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)
1582 {
1583 struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
1584 struct at_xdmac_desc *bad_desc;
1585
1586 /*
1587 * The descriptor currently at the head of the active list is
1588 * broken. Since we don't have any way to report errors, we'll
1589 * just have to scream loudly and try to continue with other
1590 * descriptors queued (if any).
1591 */
1592 if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
1593 dev_err(chan2dev(&atchan->chan), "read bus error!!!");
1594 if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
1595 dev_err(chan2dev(&atchan->chan), "write bus error!!!");
1596 if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
1597 dev_err(chan2dev(&atchan->chan), "request overflow error!!!");
1598
1599 spin_lock_bh(&atchan->lock);
1600
1601 /* Channel must be disabled first as it's not done automatically */
1602 at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1603 while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
1604 cpu_relax();
1605
1606 bad_desc = list_first_entry(&atchan->xfers_list,
1607 struct at_xdmac_desc,
1608 xfer_node);
1609
1610 spin_unlock_bh(&atchan->lock);
1611
1612 /* Print bad descriptor's details if needed */
1613 dev_dbg(chan2dev(&atchan->chan),
1614 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
1615 __func__, &bad_desc->lld.mbr_sa, &bad_desc->lld.mbr_da,
1616 bad_desc->lld.mbr_ubc);
1617
1618 /* Then continue with usual descriptor management */
1619 }
1620
1621 static void at_xdmac_tasklet(unsigned long data)
1622 {
1623 struct at_xdmac_chan *atchan = (struct at_xdmac_chan *)data;
1624 struct at_xdmac_desc *desc;
1625 u32 error_mask;
1626
1627 dev_dbg(chan2dev(&atchan->chan), "%s: status=0x%08x\n",
1628 __func__, atchan->irq_status);
1629
1630 error_mask = AT_XDMAC_CIS_RBEIS
1631 | AT_XDMAC_CIS_WBEIS
1632 | AT_XDMAC_CIS_ROIS;
1633
1634 if (at_xdmac_chan_is_cyclic(atchan)) {
1635 at_xdmac_handle_cyclic(atchan);
1636 } else if ((atchan->irq_status & AT_XDMAC_CIS_LIS)
1637 || (atchan->irq_status & error_mask)) {
1638 struct dma_async_tx_descriptor *txd;
1639
1640 if (atchan->irq_status & error_mask)
1641 at_xdmac_handle_error(atchan);
1642
1643 spin_lock(&atchan->lock);
1644 desc = list_first_entry(&atchan->xfers_list,
1645 struct at_xdmac_desc,
1646 xfer_node);
1647 dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1648 if (!desc->active_xfer) {
1649 dev_err(chan2dev(&atchan->chan), "Xfer not active: exiting");
1650 spin_unlock(&atchan->lock);
1651 return;
1652 }
1653
1654 txd = &desc->tx_dma_desc;
1655
1656 at_xdmac_remove_xfer(atchan, desc);
1657 spin_unlock(&atchan->lock);
1658
1659 if (!at_xdmac_chan_is_cyclic(atchan)) {
1660 dma_cookie_complete(txd);
1661 if (txd->flags & DMA_PREP_INTERRUPT)
1662 dmaengine_desc_get_callback_invoke(txd, NULL);
1663 }
1664
1665 dma_run_dependencies(txd);
1666
1667 at_xdmac_advance_work(atchan);
1668 }
1669 }
1670
1671 static irqreturn_t at_xdmac_interrupt(int irq, void *dev_id)
1672 {
1673 struct at_xdmac *atxdmac = (struct at_xdmac *)dev_id;
1674 struct at_xdmac_chan *atchan;
1675 u32 imr, status, pending;
1676 u32 chan_imr, chan_status;
1677 int i, ret = IRQ_NONE;
1678
1679 do {
1680 imr = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
1681 status = at_xdmac_read(atxdmac, AT_XDMAC_GIS);
1682 pending = status & imr;
1683
1684 dev_vdbg(atxdmac->dma.dev,
1685 "%s: status=0x%08x, imr=0x%08x, pending=0x%08x\n",
1686 __func__, status, imr, pending);
1687
1688 if (!pending)
1689 break;
1690
1691 /* We have to find which channel has generated the interrupt. */
1692 for (i = 0; i < atxdmac->dma.chancnt; i++) {
1693 if (!((1 << i) & pending))
1694 continue;
1695
1696 atchan = &atxdmac->chan[i];
1697 chan_imr = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
1698 chan_status = at_xdmac_chan_read(atchan, AT_XDMAC_CIS);
1699 atchan->irq_status = chan_status & chan_imr;
1700 dev_vdbg(atxdmac->dma.dev,
1701 "%s: chan%d: imr=0x%x, status=0x%x\n",
1702 __func__, i, chan_imr, chan_status);
1703 dev_vdbg(chan2dev(&atchan->chan),
1704 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
1705 __func__,
1706 at_xdmac_chan_read(atchan, AT_XDMAC_CC),
1707 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
1708 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
1709 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
1710 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
1711 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
1712
1713 if (atchan->irq_status & (AT_XDMAC_CIS_RBEIS | AT_XDMAC_CIS_WBEIS))
1714 at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1715
1716 tasklet_schedule(&atchan->tasklet);
1717 ret = IRQ_HANDLED;
1718 }
1719
1720 } while (pending);
1721
1722 return ret;
1723 }
1724
1725 static void at_xdmac_issue_pending(struct dma_chan *chan)
1726 {
1727 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1728
1729 dev_dbg(chan2dev(&atchan->chan), "%s\n", __func__);
1730
1731 if (!at_xdmac_chan_is_cyclic(atchan))
1732 at_xdmac_advance_work(atchan);
1733
1734 return;
1735 }
1736
1737 static int at_xdmac_device_config(struct dma_chan *chan,
1738 struct dma_slave_config *config)
1739 {
1740 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1741 int ret;
1742 unsigned long flags;
1743
1744 dev_dbg(chan2dev(chan), "%s\n", __func__);
1745
1746 spin_lock_irqsave(&atchan->lock, flags);
1747 ret = at_xdmac_set_slave_config(chan, config);
1748 spin_unlock_irqrestore(&atchan->lock, flags);
1749
1750 return ret;
1751 }
1752
1753 static int at_xdmac_device_pause(struct dma_chan *chan)
1754 {
1755 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1756 struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
1757 unsigned long flags;
1758
1759 dev_dbg(chan2dev(chan), "%s\n", __func__);
1760
1761 if (test_and_set_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status))
1762 return 0;
1763
1764 spin_lock_irqsave(&atchan->lock, flags);
1765 at_xdmac_write(atxdmac, AT_XDMAC_GRWS, atchan->mask);
1766 while (at_xdmac_chan_read(atchan, AT_XDMAC_CC)
1767 & (AT_XDMAC_CC_WRIP | AT_XDMAC_CC_RDIP))
1768 cpu_relax();
1769 spin_unlock_irqrestore(&atchan->lock, flags);
1770
1771 return 0;
1772 }
1773
1774 static int at_xdmac_device_resume(struct dma_chan *chan)
1775 {
1776 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1777 struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
1778 unsigned long flags;
1779
1780 dev_dbg(chan2dev(chan), "%s\n", __func__);
1781
1782 spin_lock_irqsave(&atchan->lock, flags);
1783 if (!at_xdmac_chan_is_paused(atchan)) {
1784 spin_unlock_irqrestore(&atchan->lock, flags);
1785 return 0;
1786 }
1787
1788 at_xdmac_write(atxdmac, AT_XDMAC_GRWR, atchan->mask);
1789 clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
1790 spin_unlock_irqrestore(&atchan->lock, flags);
1791
1792 return 0;
1793 }
1794
1795 static int at_xdmac_device_terminate_all(struct dma_chan *chan)
1796 {
1797 struct at_xdmac_desc *desc, *_desc;
1798 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1799 struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
1800 unsigned long flags;
1801
1802 dev_dbg(chan2dev(chan), "%s\n", __func__);
1803
1804 spin_lock_irqsave(&atchan->lock, flags);
1805 at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1806 while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
1807 cpu_relax();
1808
1809 /* Cancel all pending transfers. */
1810 list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node)
1811 at_xdmac_remove_xfer(atchan, desc);
1812
1813 clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
1814 clear_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status);
1815 spin_unlock_irqrestore(&atchan->lock, flags);
1816
1817 return 0;
1818 }
1819
1820 static int at_xdmac_alloc_chan_resources(struct dma_chan *chan)
1821 {
1822 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1823 struct at_xdmac_desc *desc;
1824 int i;
1825 unsigned long flags;
1826
1827 spin_lock_irqsave(&atchan->lock, flags);
1828
1829 if (at_xdmac_chan_is_enabled(atchan)) {
1830 dev_err(chan2dev(chan),
1831 "can't allocate channel resources (channel enabled)\n");
1832 i = -EIO;
1833 goto spin_unlock;
1834 }
1835
1836 if (!list_empty(&atchan->free_descs_list)) {
1837 dev_err(chan2dev(chan),
1838 "can't allocate channel resources (channel not free from a previous use)\n");
1839 i = -EIO;
1840 goto spin_unlock;
1841 }
1842
1843 for (i = 0; i < init_nr_desc_per_channel; i++) {
1844 desc = at_xdmac_alloc_desc(chan, GFP_ATOMIC);
1845 if (!desc) {
1846 dev_warn(chan2dev(chan),
1847 "only %d descriptors have been allocated\n", i);
1848 break;
1849 }
1850 list_add_tail(&desc->desc_node, &atchan->free_descs_list);
1851 }
1852
1853 dma_cookie_init(chan);
1854
1855 dev_dbg(chan2dev(chan), "%s: allocated %d descriptors\n", __func__, i);
1856
1857 spin_unlock:
1858 spin_unlock_irqrestore(&atchan->lock, flags);
1859 return i;
1860 }
1861
1862 static void at_xdmac_free_chan_resources(struct dma_chan *chan)
1863 {
1864 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1865 struct at_xdmac *atxdmac = to_at_xdmac(chan->device);
1866 struct at_xdmac_desc *desc, *_desc;
1867
1868 list_for_each_entry_safe(desc, _desc, &atchan->free_descs_list, desc_node) {
1869 dev_dbg(chan2dev(chan), "%s: freeing descriptor %p\n", __func__, desc);
1870 list_del(&desc->desc_node);
1871 dma_pool_free(atxdmac->at_xdmac_desc_pool, desc, desc->tx_dma_desc.phys);
1872 }
1873
1874 return;
1875 }
1876
1877 #ifdef CONFIG_PM
1878 static int atmel_xdmac_prepare(struct device *dev)
1879 {
1880 struct at_xdmac *atxdmac = dev_get_drvdata(dev);
1881 struct dma_chan *chan, *_chan;
1882
1883 list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
1884 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1885
1886 /* Wait for transfer completion, except in cyclic case. */
1887 if (at_xdmac_chan_is_enabled(atchan) && !at_xdmac_chan_is_cyclic(atchan))
1888 return -EAGAIN;
1889 }
1890 return 0;
1891 }
1892 #else
1893 # define atmel_xdmac_prepare NULL
1894 #endif
1895
1896 #ifdef CONFIG_PM_SLEEP
1897 static int atmel_xdmac_suspend(struct device *dev)
1898 {
1899 struct at_xdmac *atxdmac = dev_get_drvdata(dev);
1900 struct dma_chan *chan, *_chan;
1901
1902 list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
1903 struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
1904
1905 atchan->save_cc = at_xdmac_chan_read(atchan, AT_XDMAC_CC);
1906 if (at_xdmac_chan_is_cyclic(atchan)) {
1907 if (!at_xdmac_chan_is_paused(atchan))
1908 at_xdmac_device_pause(chan);
1909 atchan->save_cim = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
1910 atchan->save_cnda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA);
1911 atchan->save_cndc = at_xdmac_chan_read(atchan, AT_XDMAC_CNDC);
1912 }
1913 }
1914 atxdmac->save_gim = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
1915
1916 at_xdmac_off(atxdmac);
1917 clk_disable_unprepare(atxdmac->clk);
1918 return 0;
1919 }
1920
1921 static int atmel_xdmac_resume(struct device *dev)
1922 {
1923 struct at_xdmac *atxdmac = dev_get_drvdata(dev);
1924 struct at_xdmac_chan *atchan;
1925 struct dma_chan *chan, *_chan;
1926 int i;
1927 int ret;
1928
1929 ret = clk_prepare_enable(atxdmac->clk);
1930 if (ret)
1931 return ret;
1932
1933 /* Clear pending interrupts. */
1934 for (i = 0; i < atxdmac->dma.chancnt; i++) {
1935 atchan = &atxdmac->chan[i];
1936 while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
1937 cpu_relax();
1938 }
1939
1940 at_xdmac_write(atxdmac, AT_XDMAC_GIE, atxdmac->save_gim);
1941 list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
1942 atchan = to_at_xdmac_chan(chan);
1943 at_xdmac_chan_write(atchan, AT_XDMAC_CC, atchan->save_cc);
1944 if (at_xdmac_chan_is_cyclic(atchan)) {
1945 if (at_xdmac_chan_is_paused(atchan))
1946 at_xdmac_device_resume(chan);
1947 at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, atchan->save_cnda);
1948 at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, atchan->save_cndc);
1949 at_xdmac_chan_write(atchan, AT_XDMAC_CIE, atchan->save_cim);
1950 wmb();
1951 at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
1952 }
1953 }
1954 return 0;
1955 }
1956 #endif /* CONFIG_PM_SLEEP */
1957
1958 static int at_xdmac_probe(struct platform_device *pdev)
1959 {
1960 struct at_xdmac *atxdmac;
1961 int irq, size, nr_channels, i, ret;
1962 void __iomem *base;
1963 u32 reg;
1964
1965 irq = platform_get_irq(pdev, 0);
1966 if (irq < 0)
1967 return irq;
1968
1969 base = devm_platform_ioremap_resource(pdev, 0);
1970 if (IS_ERR(base))
1971 return PTR_ERR(base);
1972
1973 /*
1974 * Read number of xdmac channels, read helper function can't be used
1975 * since atxdmac is not yet allocated and we need to know the number
1976 * of channels to do the allocation.
1977 */
1978 reg = readl_relaxed(base + AT_XDMAC_GTYPE);
1979 nr_channels = AT_XDMAC_NB_CH(reg);
1980 if (nr_channels > AT_XDMAC_MAX_CHAN) {
1981 dev_err(&pdev->dev, "invalid number of channels (%u)\n",
1982 nr_channels);
1983 return -EINVAL;
1984 }
1985
1986 size = sizeof(*atxdmac);
1987 size += nr_channels * sizeof(struct at_xdmac_chan);
1988 atxdmac = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
1989 if (!atxdmac) {
1990 dev_err(&pdev->dev, "can't allocate at_xdmac structure\n");
1991 return -ENOMEM;
1992 }
1993
1994 atxdmac->regs = base;
1995 atxdmac->irq = irq;
1996
1997 atxdmac->clk = devm_clk_get(&pdev->dev, "dma_clk");
1998 if (IS_ERR(atxdmac->clk)) {
1999 dev_err(&pdev->dev, "can't get dma_clk\n");
2000 return PTR_ERR(atxdmac->clk);
2001 }
2002
2003 /* Do not use dev res to prevent races with tasklet */
2004 ret = request_irq(atxdmac->irq, at_xdmac_interrupt, 0, "at_xdmac", atxdmac);
2005 if (ret) {
2006 dev_err(&pdev->dev, "can't request irq\n");
2007 return ret;
2008 }
2009
2010 ret = clk_prepare_enable(atxdmac->clk);
2011 if (ret) {
2012 dev_err(&pdev->dev, "can't prepare or enable clock\n");
2013 goto err_free_irq;
2014 }
2015
2016 atxdmac->at_xdmac_desc_pool =
2017 dmam_pool_create(dev_name(&pdev->dev), &pdev->dev,
2018 sizeof(struct at_xdmac_desc), 4, 0);
2019 if (!atxdmac->at_xdmac_desc_pool) {
2020 dev_err(&pdev->dev, "no memory for descriptors dma pool\n");
2021 ret = -ENOMEM;
2022 goto err_clk_disable;
2023 }
2024
2025 dma_cap_set(DMA_CYCLIC, atxdmac->dma.cap_mask);
2026 dma_cap_set(DMA_INTERLEAVE, atxdmac->dma.cap_mask);
2027 dma_cap_set(DMA_MEMCPY, atxdmac->dma.cap_mask);
2028 dma_cap_set(DMA_MEMSET, atxdmac->dma.cap_mask);
2029 dma_cap_set(DMA_MEMSET_SG, atxdmac->dma.cap_mask);
2030 dma_cap_set(DMA_SLAVE, atxdmac->dma.cap_mask);
2031 /*
2032 * Without DMA_PRIVATE the driver is not able to allocate more than
2033 * one channel, second allocation fails in private_candidate.
2034 */
2035 dma_cap_set(DMA_PRIVATE, atxdmac->dma.cap_mask);
2036 atxdmac->dma.dev = &pdev->dev;
2037 atxdmac->dma.device_alloc_chan_resources = at_xdmac_alloc_chan_resources;
2038 atxdmac->dma.device_free_chan_resources = at_xdmac_free_chan_resources;
2039 atxdmac->dma.device_tx_status = at_xdmac_tx_status;
2040 atxdmac->dma.device_issue_pending = at_xdmac_issue_pending;
2041 atxdmac->dma.device_prep_dma_cyclic = at_xdmac_prep_dma_cyclic;
2042 atxdmac->dma.device_prep_interleaved_dma = at_xdmac_prep_interleaved;
2043 atxdmac->dma.device_prep_dma_memcpy = at_xdmac_prep_dma_memcpy;
2044 atxdmac->dma.device_prep_dma_memset = at_xdmac_prep_dma_memset;
2045 atxdmac->dma.device_prep_dma_memset_sg = at_xdmac_prep_dma_memset_sg;
2046 atxdmac->dma.device_prep_slave_sg = at_xdmac_prep_slave_sg;
2047 atxdmac->dma.device_config = at_xdmac_device_config;
2048 atxdmac->dma.device_pause = at_xdmac_device_pause;
2049 atxdmac->dma.device_resume = at_xdmac_device_resume;
2050 atxdmac->dma.device_terminate_all = at_xdmac_device_terminate_all;
2051 atxdmac->dma.src_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
2052 atxdmac->dma.dst_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
2053 atxdmac->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
2054 atxdmac->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
2055
2056 /* Disable all chans and interrupts. */
2057 at_xdmac_off(atxdmac);
2058
2059 /* Init channels. */
2060 INIT_LIST_HEAD(&atxdmac->dma.channels);
2061 for (i = 0; i < nr_channels; i++) {
2062 struct at_xdmac_chan *atchan = &atxdmac->chan[i];
2063
2064 atchan->chan.device = &atxdmac->dma;
2065 list_add_tail(&atchan->chan.device_node,
2066 &atxdmac->dma.channels);
2067
2068 atchan->ch_regs = at_xdmac_chan_reg_base(atxdmac, i);
2069 atchan->mask = 1 << i;
2070
2071 spin_lock_init(&atchan->lock);
2072 INIT_LIST_HEAD(&atchan->xfers_list);
2073 INIT_LIST_HEAD(&atchan->free_descs_list);
2074 tasklet_init(&atchan->tasklet, at_xdmac_tasklet,
2075 (unsigned long)atchan);
2076
2077 /* Clear pending interrupts. */
2078 while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
2079 cpu_relax();
2080 }
2081 platform_set_drvdata(pdev, atxdmac);
2082
2083 ret = dma_async_device_register(&atxdmac->dma);
2084 if (ret) {
2085 dev_err(&pdev->dev, "fail to register DMA engine device\n");
2086 goto err_clk_disable;
2087 }
2088
2089 ret = of_dma_controller_register(pdev->dev.of_node,
2090 at_xdmac_xlate, atxdmac);
2091 if (ret) {
2092 dev_err(&pdev->dev, "could not register of dma controller\n");
2093 goto err_dma_unregister;
2094 }
2095
2096 dev_info(&pdev->dev, "%d channels, mapped at 0x%p\n",
2097 nr_channels, atxdmac->regs);
2098
2099 return 0;
2100
2101 err_dma_unregister:
2102 dma_async_device_unregister(&atxdmac->dma);
2103 err_clk_disable:
2104 clk_disable_unprepare(atxdmac->clk);
2105 err_free_irq:
2106 free_irq(atxdmac->irq, atxdmac);
2107 return ret;
2108 }
2109
2110 static int at_xdmac_remove(struct platform_device *pdev)
2111 {
2112 struct at_xdmac *atxdmac = (struct at_xdmac *)platform_get_drvdata(pdev);
2113 int i;
2114
2115 at_xdmac_off(atxdmac);
2116 of_dma_controller_free(pdev->dev.of_node);
2117 dma_async_device_unregister(&atxdmac->dma);
2118 clk_disable_unprepare(atxdmac->clk);
2119
2120 free_irq(atxdmac->irq, atxdmac);
2121
2122 for (i = 0; i < atxdmac->dma.chancnt; i++) {
2123 struct at_xdmac_chan *atchan = &atxdmac->chan[i];
2124
2125 tasklet_kill(&atchan->tasklet);
2126 at_xdmac_free_chan_resources(&atchan->chan);
2127 }
2128
2129 return 0;
2130 }
2131
2132 static const struct dev_pm_ops atmel_xdmac_dev_pm_ops = {
2133 .prepare = atmel_xdmac_prepare,
2134 SET_LATE_SYSTEM_SLEEP_PM_OPS(atmel_xdmac_suspend, atmel_xdmac_resume)
2135 };
2136
2137 static const struct of_device_id atmel_xdmac_dt_ids[] = {
2138 {
2139 .compatible = "atmel,sama5d4-dma",
2140 }, {
2141 /* sentinel */
2142 }
2143 };
2144 MODULE_DEVICE_TABLE(of, atmel_xdmac_dt_ids);
2145
2146 static struct platform_driver at_xdmac_driver = {
2147 .probe = at_xdmac_probe,
2148 .remove = at_xdmac_remove,
2149 .driver = {
2150 .name = "at_xdmac",
2151 .of_match_table = of_match_ptr(atmel_xdmac_dt_ids),
2152 .pm = &atmel_xdmac_dev_pm_ops,
2153 }
2154 };
2155
2156 static int __init at_xdmac_init(void)
2157 {
2158 return platform_driver_probe(&at_xdmac_driver, at_xdmac_probe);
2159 }
2160 subsys_initcall(at_xdmac_init);
2161
2162 MODULE_DESCRIPTION("Atmel Extended DMA Controller driver");
2163 MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>");
2164 MODULE_LICENSE("GPL");
Linux with added FPC-III support