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