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#include <linux/pm_runtime.h>
25
26#include "dmaengine.h"
27
28/* Global registers */
29#define AT_XDMAC_GTYPE 0x00 /* Global Type Register */
30#define AT_XDMAC_NB_CH(i) (((i) & 0x1F) + 1) /* Number of Channels Minus One */
31#define AT_XDMAC_FIFO_SZ(i) (((i) >> 5) & 0x7FF) /* Number of Bytes */
32#define AT_XDMAC_NB_REQ(i) ((((i) >> 16) & 0x3F) + 1) /* Number of Peripheral Requests Minus One */
33#define AT_XDMAC_GCFG 0x04 /* Global Configuration Register */
34#define AT_XDMAC_WRHP(i) (((i) & 0xF) << 4)
35#define AT_XDMAC_WRMP(i) (((i) & 0xF) << 8)
36#define AT_XDMAC_WRLP(i) (((i) & 0xF) << 12)
37#define AT_XDMAC_RDHP(i) (((i) & 0xF) << 16)
38#define AT_XDMAC_RDMP(i) (((i) & 0xF) << 20)
39#define AT_XDMAC_RDLP(i) (((i) & 0xF) << 24)
40#define AT_XDMAC_RDSG(i) (((i) & 0xF) << 28)
41#define AT_XDMAC_GCFG_M2M (AT_XDMAC_RDLP(0xF) | AT_XDMAC_WRLP(0xF))
42#define AT_XDMAC_GCFG_P2M (AT_XDMAC_RDSG(0x1) | AT_XDMAC_RDHP(0x3) | \
43 AT_XDMAC_WRHP(0x5))
44#define AT_XDMAC_GWAC 0x08 /* Global Weighted Arbiter Configuration Register */
45#define AT_XDMAC_PW0(i) (((i) & 0xF) << 0)
46#define AT_XDMAC_PW1(i) (((i) & 0xF) << 4)
47#define AT_XDMAC_PW2(i) (((i) & 0xF) << 8)
48#define AT_XDMAC_PW3(i) (((i) & 0xF) << 12)
49#define AT_XDMAC_GWAC_M2M 0
50#define AT_XDMAC_GWAC_P2M (AT_XDMAC_PW0(0xF) | AT_XDMAC_PW2(0xF))
51
52#define AT_XDMAC_GIE 0x0C /* Global Interrupt Enable Register */
53#define AT_XDMAC_GID 0x10 /* Global Interrupt Disable Register */
54#define AT_XDMAC_GIM 0x14 /* Global Interrupt Mask Register */
55#define AT_XDMAC_GIS 0x18 /* Global Interrupt Status Register */
56#define AT_XDMAC_GE 0x1C /* Global Channel Enable Register */
57#define AT_XDMAC_GD 0x20 /* Global Channel Disable Register */
58#define AT_XDMAC_GS 0x24 /* Global Channel Status 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_MASK GENMASK(28, 27)
104#define AT_XDMAC_CNDC_NDVIEW_NDV0 (0x0 << 3) /* Channel x Next Descriptor View 0 */
105#define AT_XDMAC_CNDC_NDVIEW_NDV1 (0x1 << 3) /* Channel x Next Descriptor View 1 */
106#define AT_XDMAC_CNDC_NDVIEW_NDV2 (0x2 << 3) /* Channel x Next Descriptor View 2 */
107#define AT_XDMAC_CNDC_NDVIEW_NDV3 (0x3 << 3) /* Channel x Next Descriptor View 3 */
108#define AT_XDMAC_CUBC 0x20 /* Channel Microblock Control Register */
109#define AT_XDMAC_CBC 0x24 /* Channel Block Control Register */
110#define AT_XDMAC_CC 0x28 /* Channel Configuration Register */
111#define AT_XDMAC_CC_TYPE (0x1 << 0) /* Channel Transfer Type */
112#define AT_XDMAC_CC_TYPE_MEM_TRAN (0x0 << 0) /* Memory to Memory Transfer */
113#define AT_XDMAC_CC_TYPE_PER_TRAN (0x1 << 0) /* Peripheral to Memory or Memory to Peripheral Transfer */
114#define AT_XDMAC_CC_MBSIZE_MASK (0x3 << 1)
115#define AT_XDMAC_CC_MBSIZE_SINGLE (0x0 << 1)
116#define AT_XDMAC_CC_MBSIZE_FOUR (0x1 << 1)
117#define AT_XDMAC_CC_MBSIZE_EIGHT (0x2 << 1)
118#define AT_XDMAC_CC_MBSIZE_SIXTEEN (0x3 << 1)
119#define AT_XDMAC_CC_DSYNC (0x1 << 4) /* Channel Synchronization */
120#define AT_XDMAC_CC_DSYNC_PER2MEM (0x0 << 4)
121#define AT_XDMAC_CC_DSYNC_MEM2PER (0x1 << 4)
122#define AT_XDMAC_CC_PROT (0x1 << 5) /* Channel Protection */
123#define AT_XDMAC_CC_PROT_SEC (0x0 << 5)
124#define AT_XDMAC_CC_PROT_UNSEC (0x1 << 5)
125#define AT_XDMAC_CC_SWREQ (0x1 << 6) /* Channel Software Request Trigger */
126#define AT_XDMAC_CC_SWREQ_HWR_CONNECTED (0x0 << 6)
127#define AT_XDMAC_CC_SWREQ_SWR_CONNECTED (0x1 << 6)
128#define AT_XDMAC_CC_MEMSET (0x1 << 7) /* Channel Fill Block of memory */
129#define AT_XDMAC_CC_MEMSET_NORMAL_MODE (0x0 << 7)
130#define AT_XDMAC_CC_MEMSET_HW_MODE (0x1 << 7)
131#define AT_XDMAC_CC_CSIZE(i) ((0x7 & (i)) << 8) /* Channel Chunk Size */
132#define AT_XDMAC_CC_DWIDTH_OFFSET 11
133#define AT_XDMAC_CC_DWIDTH_MASK (0x3 << AT_XDMAC_CC_DWIDTH_OFFSET)
134#define AT_XDMAC_CC_DWIDTH(i) ((0x3 & (i)) << AT_XDMAC_CC_DWIDTH_OFFSET) /* Channel Data Width */
135#define AT_XDMAC_CC_DWIDTH_BYTE 0x0
136#define AT_XDMAC_CC_DWIDTH_HALFWORD 0x1
137#define AT_XDMAC_CC_DWIDTH_WORD 0x2
138#define AT_XDMAC_CC_DWIDTH_DWORD 0x3
139#define AT_XDMAC_CC_SIF(i) ((0x1 & (i)) << 13) /* Channel Source Interface Identifier */
140#define AT_XDMAC_CC_DIF(i) ((0x1 & (i)) << 14) /* Channel Destination Interface Identifier */
141#define AT_XDMAC_CC_SAM_MASK (0x3 << 16) /* Channel Source Addressing Mode */
142#define AT_XDMAC_CC_SAM_FIXED_AM (0x0 << 16)
143#define AT_XDMAC_CC_SAM_INCREMENTED_AM (0x1 << 16)
144#define AT_XDMAC_CC_SAM_UBS_AM (0x2 << 16)
145#define AT_XDMAC_CC_SAM_UBS_DS_AM (0x3 << 16)
146#define AT_XDMAC_CC_DAM_MASK (0x3 << 18) /* Channel Source Addressing Mode */
147#define AT_XDMAC_CC_DAM_FIXED_AM (0x0 << 18)
148#define AT_XDMAC_CC_DAM_INCREMENTED_AM (0x1 << 18)
149#define AT_XDMAC_CC_DAM_UBS_AM (0x2 << 18)
150#define AT_XDMAC_CC_DAM_UBS_DS_AM (0x3 << 18)
151#define AT_XDMAC_CC_INITD (0x1 << 21) /* Channel Initialization Terminated (read only) */
152#define AT_XDMAC_CC_INITD_TERMINATED (0x0 << 21)
153#define AT_XDMAC_CC_INITD_IN_PROGRESS (0x1 << 21)
154#define AT_XDMAC_CC_RDIP (0x1 << 22) /* Read in Progress (read only) */
155#define AT_XDMAC_CC_RDIP_DONE (0x0 << 22)
156#define AT_XDMAC_CC_RDIP_IN_PROGRESS (0x1 << 22)
157#define AT_XDMAC_CC_WRIP (0x1 << 23) /* Write in Progress (read only) */
158#define AT_XDMAC_CC_WRIP_DONE (0x0 << 23)
159#define AT_XDMAC_CC_WRIP_IN_PROGRESS (0x1 << 23)
160#define AT_XDMAC_CC_PERID(i) ((0x7f & (i)) << 24) /* Channel Peripheral Identifier */
161#define AT_XDMAC_CDS_MSP 0x2C /* Channel Data Stride Memory Set Pattern */
162#define AT_XDMAC_CSUS 0x30 /* Channel Source Microblock Stride */
163#define AT_XDMAC_CDUS 0x34 /* Channel Destination Microblock Stride */
164
165/* Microblock control members */
166#define AT_XDMAC_MBR_UBC_UBLEN_MAX 0xFFFFFFUL /* Maximum Microblock Length */
167#define AT_XDMAC_MBR_UBC_NDE (0x1 << 24) /* Next Descriptor Enable */
168#define AT_XDMAC_MBR_UBC_NSEN (0x1 << 25) /* Next Descriptor Source Update */
169#define AT_XDMAC_MBR_UBC_NDEN (0x1 << 26) /* Next Descriptor Destination Update */
170#define AT_XDMAC_MBR_UBC_NDV0 (0x0 << 27) /* Next Descriptor View 0 */
171#define AT_XDMAC_MBR_UBC_NDV1 (0x1 << 27) /* Next Descriptor View 1 */
172#define AT_XDMAC_MBR_UBC_NDV2 (0x2 << 27) /* Next Descriptor View 2 */
173#define AT_XDMAC_MBR_UBC_NDV3 (0x3 << 27) /* Next Descriptor View 3 */
174
175#define AT_XDMAC_MAX_CHAN 0x20
176#define AT_XDMAC_MAX_CSIZE 16 /* 16 data */
177#define AT_XDMAC_MAX_DWIDTH 8 /* 64 bits */
178#define AT_XDMAC_RESIDUE_MAX_RETRIES 5
179
180#define AT_XDMAC_DMA_BUSWIDTHS\
181 (BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) |\
182 BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |\
183 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |\
184 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |\
185 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES))
186
187enum atc_status {
188 AT_XDMAC_CHAN_IS_CYCLIC = 0,
189 AT_XDMAC_CHAN_IS_PAUSED,
190 AT_XDMAC_CHAN_IS_PAUSED_INTERNAL,
191};
192
193struct at_xdmac_layout {
194 /* Global Channel Read Suspend Register */
195 u8 grs;
196 /* Global Write Suspend Register */
197 u8 gws;
198 /* Global Channel Read Write Suspend Register */
199 u8 grws;
200 /* Global Channel Read Write Resume Register */
201 u8 grwr;
202 /* Global Channel Software Request Register */
203 u8 gswr;
204 /* Global channel Software Request Status Register */
205 u8 gsws;
206 /* Global Channel Software Flush Request Register */
207 u8 gswf;
208 /* Channel reg base */
209 u8 chan_cc_reg_base;
210 /* Source/Destination Interface must be specified or not */
211 bool sdif;
212 /* AXI queue priority configuration supported */
213 bool axi_config;
214};
215
216/* ----- Channels ----- */
217struct at_xdmac_chan {
218 struct dma_chan chan;
219 void __iomem *ch_regs;
220 u32 mask; /* Channel Mask */
221 u32 cfg; /* Channel Configuration Register */
222 u8 perid; /* Peripheral ID */
223 u8 perif; /* Peripheral Interface */
224 u8 memif; /* Memory Interface */
225 u32 save_cc;
226 u32 save_cim;
227 u32 save_cnda;
228 u32 save_cndc;
229 u32 irq_status;
230 unsigned long status;
231 struct tasklet_struct tasklet;
232 struct dma_slave_config sconfig;
233
234 spinlock_t lock;
235
236 struct list_head xfers_list;
237 struct list_head free_descs_list;
238};
239
240
241/* ----- Controller ----- */
242struct at_xdmac {
243 struct dma_device dma;
244 void __iomem *regs;
245 struct device *dev;
246 int irq;
247 struct clk *clk;
248 u32 save_gim;
249 u32 save_gs;
250 struct dma_pool *at_xdmac_desc_pool;
251 const struct at_xdmac_layout *layout;
252 struct at_xdmac_chan chan[];
253};
254
255
256/* ----- Descriptors ----- */
257
258/* Linked List Descriptor */
259struct at_xdmac_lld {
260 u32 mbr_nda; /* Next Descriptor Member */
261 u32 mbr_ubc; /* Microblock Control Member */
262 u32 mbr_sa; /* Source Address Member */
263 u32 mbr_da; /* Destination Address Member */
264 u32 mbr_cfg; /* Configuration Register */
265 u32 mbr_bc; /* Block Control Register */
266 u32 mbr_ds; /* Data Stride Register */
267 u32 mbr_sus; /* Source Microblock Stride Register */
268 u32 mbr_dus; /* Destination Microblock Stride Register */
269};
270
271/* 64-bit alignment needed to update CNDA and CUBC registers in an atomic way. */
272struct at_xdmac_desc {
273 struct at_xdmac_lld lld;
274 enum dma_transfer_direction direction;
275 struct dma_async_tx_descriptor tx_dma_desc;
276 struct list_head desc_node;
277 /* Following members are only used by the first descriptor */
278 bool active_xfer;
279 unsigned int xfer_size;
280 struct list_head descs_list;
281 struct list_head xfer_node;
282} __aligned(sizeof(u64));
283
284static const struct at_xdmac_layout at_xdmac_sama5d4_layout = {
285 .grs = 0x28,
286 .gws = 0x2C,
287 .grws = 0x30,
288 .grwr = 0x34,
289 .gswr = 0x38,
290 .gsws = 0x3C,
291 .gswf = 0x40,
292 .chan_cc_reg_base = 0x50,
293 .sdif = true,
294 .axi_config = false,
295};
296
297static const struct at_xdmac_layout at_xdmac_sama7g5_layout = {
298 .grs = 0x30,
299 .gws = 0x38,
300 .grws = 0x40,
301 .grwr = 0x44,
302 .gswr = 0x48,
303 .gsws = 0x4C,
304 .gswf = 0x50,
305 .chan_cc_reg_base = 0x60,
306 .sdif = false,
307 .axi_config = true,
308};
309
310static inline void __iomem *at_xdmac_chan_reg_base(struct at_xdmac *atxdmac, unsigned int chan_nb)
311{
312 return atxdmac->regs + (atxdmac->layout->chan_cc_reg_base + chan_nb * 0x40);
313}
314
315#define at_xdmac_read(atxdmac, reg) readl_relaxed((atxdmac)->regs + (reg))
316#define at_xdmac_write(atxdmac, reg, value) \
317 writel_relaxed((value), (atxdmac)->regs + (reg))
318
319#define at_xdmac_chan_read(atchan, reg) readl_relaxed((atchan)->ch_regs + (reg))
320#define at_xdmac_chan_write(atchan, reg, value) writel_relaxed((value), (atchan)->ch_regs + (reg))
321
322static inline struct at_xdmac_chan *to_at_xdmac_chan(struct dma_chan *dchan)
323{
324 return container_of(dchan, struct at_xdmac_chan, chan);
325}
326
327static struct device *chan2dev(struct dma_chan *chan)
328{
329 return &chan->dev->device;
330}
331
332static inline struct at_xdmac *to_at_xdmac(struct dma_device *ddev)
333{
334 return container_of(ddev, struct at_xdmac, dma);
335}
336
337static inline struct at_xdmac_desc *txd_to_at_desc(struct dma_async_tx_descriptor *txd)
338{
339 return container_of(txd, struct at_xdmac_desc, tx_dma_desc);
340}
341
342static inline int at_xdmac_chan_is_cyclic(struct at_xdmac_chan *atchan)
343{
344 return test_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status);
345}
346
347static inline int at_xdmac_chan_is_paused(struct at_xdmac_chan *atchan)
348{
349 return test_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
350}
351
352static inline int at_xdmac_chan_is_paused_internal(struct at_xdmac_chan *atchan)
353{
354 return test_bit(AT_XDMAC_CHAN_IS_PAUSED_INTERNAL, &atchan->status);
355}
356
357static inline bool at_xdmac_chan_is_peripheral_xfer(u32 cfg)
358{
359 return cfg & AT_XDMAC_CC_TYPE_PER_TRAN;
360}
361
362static inline u8 at_xdmac_get_dwidth(u32 cfg)
363{
364 return (cfg & AT_XDMAC_CC_DWIDTH_MASK) >> AT_XDMAC_CC_DWIDTH_OFFSET;
365};
366
367static unsigned int init_nr_desc_per_channel = 64;
368module_param(init_nr_desc_per_channel, uint, 0644);
369MODULE_PARM_DESC(init_nr_desc_per_channel,
370 "initial descriptors per channel (default: 64)");
371
372
373static void at_xdmac_runtime_suspend_descriptors(struct at_xdmac_chan *atchan)
374{
375 struct at_xdmac *atxdmac = to_at_xdmac(ddev: atchan->chan.device);
376 struct at_xdmac_desc *desc, *_desc;
377
378 list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node) {
379 if (!desc->active_xfer)
380 continue;
381
382 pm_runtime_mark_last_busy(dev: atxdmac->dev);
383 pm_runtime_put_autosuspend(dev: atxdmac->dev);
384 }
385}
386
387static int at_xdmac_runtime_resume_descriptors(struct at_xdmac_chan *atchan)
388{
389 struct at_xdmac *atxdmac = to_at_xdmac(ddev: atchan->chan.device);
390 struct at_xdmac_desc *desc, *_desc;
391 int ret;
392
393 list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node) {
394 if (!desc->active_xfer)
395 continue;
396
397 ret = pm_runtime_resume_and_get(dev: atxdmac->dev);
398 if (ret < 0)
399 return ret;
400 }
401
402 return 0;
403}
404
405static bool at_xdmac_chan_is_enabled(struct at_xdmac_chan *atchan)
406{
407 struct at_xdmac *atxdmac = to_at_xdmac(ddev: atchan->chan.device);
408 int ret;
409
410 ret = pm_runtime_resume_and_get(dev: atxdmac->dev);
411 if (ret < 0)
412 return false;
413
414 ret = !!(at_xdmac_chan_read(atchan, AT_XDMAC_GS) & atchan->mask);
415
416 pm_runtime_mark_last_busy(dev: atxdmac->dev);
417 pm_runtime_put_autosuspend(dev: atxdmac->dev);
418
419 return ret;
420}
421
422static void at_xdmac_off(struct at_xdmac *atxdmac, bool suspend_descriptors)
423{
424 struct dma_chan *chan, *_chan;
425 struct at_xdmac_chan *atchan;
426 int ret;
427
428 ret = pm_runtime_resume_and_get(dev: atxdmac->dev);
429 if (ret < 0)
430 return;
431
432 at_xdmac_write(atxdmac, AT_XDMAC_GD, -1L);
433
434 /* Wait that all chans are disabled. */
435 while (at_xdmac_read(atxdmac, AT_XDMAC_GS))
436 cpu_relax();
437
438 at_xdmac_write(atxdmac, AT_XDMAC_GID, -1L);
439
440 /* Decrement runtime PM ref counter for each active descriptor. */
441 if (!list_empty(head: &atxdmac->dma.channels) && suspend_descriptors) {
442 list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels,
443 device_node) {
444 atchan = to_at_xdmac_chan(dchan: chan);
445 at_xdmac_runtime_suspend_descriptors(atchan);
446 }
447 }
448
449 pm_runtime_mark_last_busy(dev: atxdmac->dev);
450 pm_runtime_put_autosuspend(dev: atxdmac->dev);
451}
452
453/* Call with lock hold. */
454static void at_xdmac_start_xfer(struct at_xdmac_chan *atchan,
455 struct at_xdmac_desc *first)
456{
457 struct at_xdmac *atxdmac = to_at_xdmac(ddev: atchan->chan.device);
458 u32 reg;
459 int ret;
460
461 ret = pm_runtime_resume_and_get(dev: atxdmac->dev);
462 if (ret < 0)
463 return;
464
465 dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, first);
466
467 /* Set transfer as active to not try to start it again. */
468 first->active_xfer = true;
469
470 /* Tell xdmac where to get the first descriptor. */
471 reg = AT_XDMAC_CNDA_NDA(first->tx_dma_desc.phys);
472 if (atxdmac->layout->sdif)
473 reg |= AT_XDMAC_CNDA_NDAIF(atchan->memif);
474
475 at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, reg);
476
477 /*
478 * When doing non cyclic transfer we need to use the next
479 * descriptor view 2 since some fields of the configuration register
480 * depend on transfer size and src/dest addresses.
481 */
482 if (at_xdmac_chan_is_cyclic(atchan))
483 reg = AT_XDMAC_CNDC_NDVIEW_NDV1;
484 else if ((first->lld.mbr_ubc &
485 AT_XDMAC_CNDC_NDVIEW_MASK) == AT_XDMAC_MBR_UBC_NDV3)
486 reg = AT_XDMAC_CNDC_NDVIEW_NDV3;
487 else
488 reg = AT_XDMAC_CNDC_NDVIEW_NDV2;
489 /*
490 * Even if the register will be updated from the configuration in the
491 * descriptor when using view 2 or higher, the PROT bit won't be set
492 * properly. This bit can be modified only by using the channel
493 * configuration register.
494 */
495 at_xdmac_chan_write(atchan, AT_XDMAC_CC, first->lld.mbr_cfg);
496
497 reg |= AT_XDMAC_CNDC_NDDUP
498 | AT_XDMAC_CNDC_NDSUP
499 | AT_XDMAC_CNDC_NDE;
500 at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, reg);
501
502 dev_vdbg(chan2dev(&atchan->chan),
503 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
504 __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
505 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
506 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
507 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
508 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
509 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
510
511 at_xdmac_chan_write(atchan, AT_XDMAC_CID, 0xffffffff);
512 reg = AT_XDMAC_CIE_RBEIE | AT_XDMAC_CIE_WBEIE;
513 /*
514 * Request Overflow Error is only for peripheral synchronized transfers
515 */
516 if (at_xdmac_chan_is_peripheral_xfer(cfg: first->lld.mbr_cfg))
517 reg |= AT_XDMAC_CIE_ROIE;
518
519 /*
520 * There is no end of list when doing cyclic dma, we need to get
521 * an interrupt after each periods.
522 */
523 if (at_xdmac_chan_is_cyclic(atchan))
524 at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
525 reg | AT_XDMAC_CIE_BIE);
526 else
527 at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
528 reg | AT_XDMAC_CIE_LIE);
529 at_xdmac_write(atxdmac, AT_XDMAC_GIE, atchan->mask);
530 dev_vdbg(chan2dev(&atchan->chan),
531 "%s: enable channel (0x%08x)\n", __func__, atchan->mask);
532 wmb();
533 at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
534
535 dev_vdbg(chan2dev(&atchan->chan),
536 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
537 __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
538 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
539 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
540 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
541 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
542 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
543}
544
545static dma_cookie_t at_xdmac_tx_submit(struct dma_async_tx_descriptor *tx)
546{
547 struct at_xdmac_desc *desc = txd_to_at_desc(txd: tx);
548 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: tx->chan);
549 dma_cookie_t cookie;
550 unsigned long irqflags;
551
552 spin_lock_irqsave(&atchan->lock, irqflags);
553 cookie = dma_cookie_assign(tx);
554
555 list_add_tail(new: &desc->xfer_node, head: &atchan->xfers_list);
556 spin_unlock_irqrestore(lock: &atchan->lock, flags: irqflags);
557
558 dev_vdbg(chan2dev(tx->chan), "%s: atchan 0x%p, add desc 0x%p to xfers_list\n",
559 __func__, atchan, desc);
560
561 return cookie;
562}
563
564static struct at_xdmac_desc *at_xdmac_alloc_desc(struct dma_chan *chan,
565 gfp_t gfp_flags)
566{
567 struct at_xdmac_desc *desc;
568 struct at_xdmac *atxdmac = to_at_xdmac(ddev: chan->device);
569 dma_addr_t phys;
570
571 desc = dma_pool_zalloc(pool: atxdmac->at_xdmac_desc_pool, mem_flags: gfp_flags, handle: &phys);
572 if (desc) {
573 INIT_LIST_HEAD(list: &desc->descs_list);
574 dma_async_tx_descriptor_init(tx: &desc->tx_dma_desc, chan);
575 desc->tx_dma_desc.tx_submit = at_xdmac_tx_submit;
576 desc->tx_dma_desc.phys = phys;
577 }
578
579 return desc;
580}
581
582static void at_xdmac_init_used_desc(struct at_xdmac_desc *desc)
583{
584 memset(&desc->lld, 0, sizeof(desc->lld));
585 INIT_LIST_HEAD(list: &desc->descs_list);
586 desc->direction = DMA_TRANS_NONE;
587 desc->xfer_size = 0;
588 desc->active_xfer = false;
589}
590
591/* Call must be protected by lock. */
592static struct at_xdmac_desc *at_xdmac_get_desc(struct at_xdmac_chan *atchan)
593{
594 struct at_xdmac_desc *desc;
595
596 if (list_empty(head: &atchan->free_descs_list)) {
597 desc = at_xdmac_alloc_desc(chan: &atchan->chan, GFP_NOWAIT);
598 } else {
599 desc = list_first_entry(&atchan->free_descs_list,
600 struct at_xdmac_desc, desc_node);
601 list_del(entry: &desc->desc_node);
602 at_xdmac_init_used_desc(desc);
603 }
604
605 return desc;
606}
607
608static void at_xdmac_queue_desc(struct dma_chan *chan,
609 struct at_xdmac_desc *prev,
610 struct at_xdmac_desc *desc)
611{
612 if (!prev || !desc)
613 return;
614
615 prev->lld.mbr_nda = desc->tx_dma_desc.phys;
616 prev->lld.mbr_ubc |= AT_XDMAC_MBR_UBC_NDE;
617
618 dev_dbg(chan2dev(chan), "%s: chain lld: prev=0x%p, mbr_nda=%pad\n",
619 __func__, prev, &prev->lld.mbr_nda);
620}
621
622static inline void at_xdmac_increment_block_count(struct dma_chan *chan,
623 struct at_xdmac_desc *desc)
624{
625 if (!desc)
626 return;
627
628 desc->lld.mbr_bc++;
629
630 dev_dbg(chan2dev(chan),
631 "%s: incrementing the block count of the desc 0x%p\n",
632 __func__, desc);
633}
634
635static struct dma_chan *at_xdmac_xlate(struct of_phandle_args *dma_spec,
636 struct of_dma *of_dma)
637{
638 struct at_xdmac *atxdmac = of_dma->of_dma_data;
639 struct at_xdmac_chan *atchan;
640 struct dma_chan *chan;
641 struct device *dev = atxdmac->dma.dev;
642
643 if (dma_spec->args_count != 1) {
644 dev_err(dev, "dma phandler args: bad number of args\n");
645 return NULL;
646 }
647
648 chan = dma_get_any_slave_channel(device: &atxdmac->dma);
649 if (!chan) {
650 dev_err(dev, "can't get a dma channel\n");
651 return NULL;
652 }
653
654 atchan = to_at_xdmac_chan(dchan: chan);
655 atchan->memif = AT91_XDMAC_DT_GET_MEM_IF(dma_spec->args[0]);
656 atchan->perif = AT91_XDMAC_DT_GET_PER_IF(dma_spec->args[0]);
657 atchan->perid = AT91_XDMAC_DT_GET_PERID(dma_spec->args[0]);
658 dev_dbg(dev, "chan dt cfg: memif=%u perif=%u perid=%u\n",
659 atchan->memif, atchan->perif, atchan->perid);
660
661 return chan;
662}
663
664static int at_xdmac_compute_chan_conf(struct dma_chan *chan,
665 enum dma_transfer_direction direction)
666{
667 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
668 struct at_xdmac *atxdmac = to_at_xdmac(ddev: atchan->chan.device);
669 int csize, dwidth;
670
671 if (direction == DMA_DEV_TO_MEM) {
672 atchan->cfg =
673 AT91_XDMAC_DT_PERID(atchan->perid)
674 | AT_XDMAC_CC_DAM_INCREMENTED_AM
675 | AT_XDMAC_CC_SAM_FIXED_AM
676 | AT_XDMAC_CC_SWREQ_HWR_CONNECTED
677 | AT_XDMAC_CC_DSYNC_PER2MEM
678 | AT_XDMAC_CC_MBSIZE_SIXTEEN
679 | AT_XDMAC_CC_TYPE_PER_TRAN;
680 if (atxdmac->layout->sdif)
681 atchan->cfg |= AT_XDMAC_CC_DIF(atchan->memif) |
682 AT_XDMAC_CC_SIF(atchan->perif);
683
684 csize = ffs(atchan->sconfig.src_maxburst) - 1;
685 if (csize < 0) {
686 dev_err(chan2dev(chan), "invalid src maxburst value\n");
687 return -EINVAL;
688 }
689 atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
690 dwidth = ffs(atchan->sconfig.src_addr_width) - 1;
691 if (dwidth < 0) {
692 dev_err(chan2dev(chan), "invalid src addr width value\n");
693 return -EINVAL;
694 }
695 atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
696 } else if (direction == DMA_MEM_TO_DEV) {
697 atchan->cfg =
698 AT91_XDMAC_DT_PERID(atchan->perid)
699 | AT_XDMAC_CC_DAM_FIXED_AM
700 | AT_XDMAC_CC_SAM_INCREMENTED_AM
701 | AT_XDMAC_CC_SWREQ_HWR_CONNECTED
702 | AT_XDMAC_CC_DSYNC_MEM2PER
703 | AT_XDMAC_CC_MBSIZE_SIXTEEN
704 | AT_XDMAC_CC_TYPE_PER_TRAN;
705 if (atxdmac->layout->sdif)
706 atchan->cfg |= AT_XDMAC_CC_DIF(atchan->perif) |
707 AT_XDMAC_CC_SIF(atchan->memif);
708
709 csize = ffs(atchan->sconfig.dst_maxburst) - 1;
710 if (csize < 0) {
711 dev_err(chan2dev(chan), "invalid src maxburst value\n");
712 return -EINVAL;
713 }
714 atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
715 dwidth = ffs(atchan->sconfig.dst_addr_width) - 1;
716 if (dwidth < 0) {
717 dev_err(chan2dev(chan), "invalid dst addr width value\n");
718 return -EINVAL;
719 }
720 atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
721 }
722
723 dev_dbg(chan2dev(chan), "%s: cfg=0x%08x\n", __func__, atchan->cfg);
724
725 return 0;
726}
727
728/*
729 * Only check that maxburst and addr width values are supported by
730 * the controller but not that the configuration is good to perform the
731 * transfer since we don't know the direction at this stage.
732 */
733static int at_xdmac_check_slave_config(struct dma_slave_config *sconfig)
734{
735 if ((sconfig->src_maxburst > AT_XDMAC_MAX_CSIZE)
736 || (sconfig->dst_maxburst > AT_XDMAC_MAX_CSIZE))
737 return -EINVAL;
738
739 if ((sconfig->src_addr_width > AT_XDMAC_MAX_DWIDTH)
740 || (sconfig->dst_addr_width > AT_XDMAC_MAX_DWIDTH))
741 return -EINVAL;
742
743 return 0;
744}
745
746static int at_xdmac_set_slave_config(struct dma_chan *chan,
747 struct dma_slave_config *sconfig)
748{
749 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
750
751 if (at_xdmac_check_slave_config(sconfig)) {
752 dev_err(chan2dev(chan), "invalid slave configuration\n");
753 return -EINVAL;
754 }
755
756 memcpy(&atchan->sconfig, sconfig, sizeof(atchan->sconfig));
757
758 return 0;
759}
760
761static struct dma_async_tx_descriptor *
762at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
763 unsigned int sg_len, enum dma_transfer_direction direction,
764 unsigned long flags, void *context)
765{
766 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
767 struct at_xdmac_desc *first = NULL, *prev = NULL;
768 struct scatterlist *sg;
769 int i;
770 unsigned int xfer_size = 0;
771 unsigned long irqflags;
772 struct dma_async_tx_descriptor *ret = NULL;
773
774 if (!sgl)
775 return NULL;
776
777 if (!is_slave_direction(direction)) {
778 dev_err(chan2dev(chan), "invalid DMA direction\n");
779 return NULL;
780 }
781
782 dev_dbg(chan2dev(chan), "%s: sg_len=%d, dir=%s, flags=0x%lx\n",
783 __func__, sg_len,
784 direction == DMA_MEM_TO_DEV ? "to device" : "from device",
785 flags);
786
787 /* Protect dma_sconfig field that can be modified by set_slave_conf. */
788 spin_lock_irqsave(&atchan->lock, irqflags);
789
790 if (at_xdmac_compute_chan_conf(chan, direction))
791 goto spin_unlock;
792
793 /* Prepare descriptors. */
794 for_each_sg(sgl, sg, sg_len, i) {
795 struct at_xdmac_desc *desc = NULL;
796 u32 len, mem, dwidth, fixed_dwidth;
797
798 len = sg_dma_len(sg);
799 mem = sg_dma_address(sg);
800 if (unlikely(!len)) {
801 dev_err(chan2dev(chan), "sg data length is zero\n");
802 goto spin_unlock;
803 }
804 dev_dbg(chan2dev(chan), "%s: * sg%d len=%u, mem=0x%08x\n",
805 __func__, i, len, mem);
806
807 desc = at_xdmac_get_desc(atchan);
808 if (!desc) {
809 dev_err(chan2dev(chan), "can't get descriptor\n");
810 if (first)
811 list_splice_tail_init(list: &first->descs_list,
812 head: &atchan->free_descs_list);
813 goto spin_unlock;
814 }
815
816 /* Linked list descriptor setup. */
817 if (direction == DMA_DEV_TO_MEM) {
818 desc->lld.mbr_sa = atchan->sconfig.src_addr;
819 desc->lld.mbr_da = mem;
820 } else {
821 desc->lld.mbr_sa = mem;
822 desc->lld.mbr_da = atchan->sconfig.dst_addr;
823 }
824 dwidth = at_xdmac_get_dwidth(cfg: atchan->cfg);
825 fixed_dwidth = IS_ALIGNED(len, 1 << dwidth)
826 ? dwidth
827 : AT_XDMAC_CC_DWIDTH_BYTE;
828 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2 /* next descriptor view */
829 | AT_XDMAC_MBR_UBC_NDEN /* next descriptor dst parameter update */
830 | AT_XDMAC_MBR_UBC_NSEN /* next descriptor src parameter update */
831 | (len >> fixed_dwidth); /* microblock length */
832 desc->lld.mbr_cfg = (atchan->cfg & ~AT_XDMAC_CC_DWIDTH_MASK) |
833 AT_XDMAC_CC_DWIDTH(fixed_dwidth);
834 dev_dbg(chan2dev(chan),
835 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
836 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
837
838 /* Chain lld. */
839 if (prev)
840 at_xdmac_queue_desc(chan, prev, desc);
841
842 prev = desc;
843 if (!first)
844 first = desc;
845
846 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
847 __func__, desc, first);
848 list_add_tail(new: &desc->desc_node, head: &first->descs_list);
849 xfer_size += len;
850 }
851
852
853 first->tx_dma_desc.flags = flags;
854 first->xfer_size = xfer_size;
855 first->direction = direction;
856 ret = &first->tx_dma_desc;
857
858spin_unlock:
859 spin_unlock_irqrestore(lock: &atchan->lock, flags: irqflags);
860 return ret;
861}
862
863static struct dma_async_tx_descriptor *
864at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr,
865 size_t buf_len, size_t period_len,
866 enum dma_transfer_direction direction,
867 unsigned long flags)
868{
869 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
870 struct at_xdmac_desc *first = NULL, *prev = NULL;
871 unsigned int periods = buf_len / period_len;
872 int i;
873 unsigned long irqflags;
874
875 dev_dbg(chan2dev(chan), "%s: buf_addr=%pad, buf_len=%zd, period_len=%zd, dir=%s, flags=0x%lx\n",
876 __func__, &buf_addr, buf_len, period_len,
877 direction == DMA_MEM_TO_DEV ? "mem2per" : "per2mem", flags);
878
879 if (!is_slave_direction(direction)) {
880 dev_err(chan2dev(chan), "invalid DMA direction\n");
881 return NULL;
882 }
883
884 if (test_and_set_bit(nr: AT_XDMAC_CHAN_IS_CYCLIC, addr: &atchan->status)) {
885 dev_err(chan2dev(chan), "channel currently used\n");
886 return NULL;
887 }
888
889 if (at_xdmac_compute_chan_conf(chan, direction))
890 return NULL;
891
892 for (i = 0; i < periods; i++) {
893 struct at_xdmac_desc *desc = NULL;
894
895 spin_lock_irqsave(&atchan->lock, irqflags);
896 desc = at_xdmac_get_desc(atchan);
897 if (!desc) {
898 dev_err(chan2dev(chan), "can't get descriptor\n");
899 if (first)
900 list_splice_tail_init(list: &first->descs_list,
901 head: &atchan->free_descs_list);
902 spin_unlock_irqrestore(lock: &atchan->lock, flags: irqflags);
903 return NULL;
904 }
905 spin_unlock_irqrestore(lock: &atchan->lock, flags: irqflags);
906 dev_dbg(chan2dev(chan),
907 "%s: desc=0x%p, tx_dma_desc.phys=%pad\n",
908 __func__, desc, &desc->tx_dma_desc.phys);
909
910 if (direction == DMA_DEV_TO_MEM) {
911 desc->lld.mbr_sa = atchan->sconfig.src_addr;
912 desc->lld.mbr_da = buf_addr + i * period_len;
913 } else {
914 desc->lld.mbr_sa = buf_addr + i * period_len;
915 desc->lld.mbr_da = atchan->sconfig.dst_addr;
916 }
917 desc->lld.mbr_cfg = atchan->cfg;
918 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV1
919 | AT_XDMAC_MBR_UBC_NDEN
920 | AT_XDMAC_MBR_UBC_NSEN
921 | period_len >> at_xdmac_get_dwidth(cfg: desc->lld.mbr_cfg);
922
923 dev_dbg(chan2dev(chan),
924 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
925 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
926
927 /* Chain lld. */
928 if (prev)
929 at_xdmac_queue_desc(chan, prev, desc);
930
931 prev = desc;
932 if (!first)
933 first = desc;
934
935 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
936 __func__, desc, first);
937 list_add_tail(new: &desc->desc_node, head: &first->descs_list);
938 }
939
940 at_xdmac_queue_desc(chan, prev, desc: first);
941 first->tx_dma_desc.flags = flags;
942 first->xfer_size = buf_len;
943 first->direction = direction;
944
945 return &first->tx_dma_desc;
946}
947
948static inline u32 at_xdmac_align_width(struct dma_chan *chan, dma_addr_t addr)
949{
950 u32 width;
951
952 /*
953 * Check address alignment to select the greater data width we
954 * can use.
955 *
956 * Some XDMAC implementations don't provide dword transfer, in
957 * this case selecting dword has the same behavior as
958 * selecting word transfers.
959 */
960 if (!(addr & 7)) {
961 width = AT_XDMAC_CC_DWIDTH_DWORD;
962 dev_dbg(chan2dev(chan), "%s: dwidth: double word\n", __func__);
963 } else if (!(addr & 3)) {
964 width = AT_XDMAC_CC_DWIDTH_WORD;
965 dev_dbg(chan2dev(chan), "%s: dwidth: word\n", __func__);
966 } else if (!(addr & 1)) {
967 width = AT_XDMAC_CC_DWIDTH_HALFWORD;
968 dev_dbg(chan2dev(chan), "%s: dwidth: half word\n", __func__);
969 } else {
970 width = AT_XDMAC_CC_DWIDTH_BYTE;
971 dev_dbg(chan2dev(chan), "%s: dwidth: byte\n", __func__);
972 }
973
974 return width;
975}
976
977static struct at_xdmac_desc *
978at_xdmac_interleaved_queue_desc(struct dma_chan *chan,
979 struct at_xdmac_chan *atchan,
980 struct at_xdmac_desc *prev,
981 dma_addr_t src, dma_addr_t dst,
982 struct dma_interleaved_template *xt,
983 struct data_chunk *chunk)
984{
985 struct at_xdmac_desc *desc;
986 u32 dwidth;
987 unsigned long flags;
988 size_t ublen;
989 /*
990 * WARNING: The channel configuration is set here since there is no
991 * dmaengine_slave_config call in this case. Moreover we don't know the
992 * direction, it involves we can't dynamically set the source and dest
993 * interface so we have to use the same one. Only interface 0 allows EBI
994 * access. Hopefully we can access DDR through both ports (at least on
995 * SAMA5D4x), so we can use the same interface for source and dest,
996 * that solves the fact we don't know the direction.
997 * ERRATA: Even if useless for memory transfers, the PERID has to not
998 * match the one of another channel. If not, it could lead to spurious
999 * flag status.
1000 * For SAMA7G5x case, the SIF and DIF fields are no longer used.
1001 * Thus, no need to have the SIF/DIF interfaces here.
1002 * For SAMA5D4x and SAMA5D2x the SIF and DIF are already configured as
1003 * zero.
1004 */
1005 u32 chan_cc = AT_XDMAC_CC_PERID(0x7f)
1006 | AT_XDMAC_CC_MBSIZE_SIXTEEN
1007 | AT_XDMAC_CC_TYPE_MEM_TRAN;
1008
1009 dwidth = at_xdmac_align_width(chan, addr: src | dst | chunk->size);
1010 if (chunk->size >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
1011 dev_dbg(chan2dev(chan),
1012 "%s: chunk too big (%zu, max size %lu)...\n",
1013 __func__, chunk->size,
1014 AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth);
1015 return NULL;
1016 }
1017
1018 if (prev)
1019 dev_dbg(chan2dev(chan),
1020 "Adding items at the end of desc 0x%p\n", prev);
1021
1022 if (xt->src_inc) {
1023 if (xt->src_sgl)
1024 chan_cc |= AT_XDMAC_CC_SAM_UBS_AM;
1025 else
1026 chan_cc |= AT_XDMAC_CC_SAM_INCREMENTED_AM;
1027 }
1028
1029 if (xt->dst_inc) {
1030 if (xt->dst_sgl)
1031 chan_cc |= AT_XDMAC_CC_DAM_UBS_AM;
1032 else
1033 chan_cc |= AT_XDMAC_CC_DAM_INCREMENTED_AM;
1034 }
1035
1036 spin_lock_irqsave(&atchan->lock, flags);
1037 desc = at_xdmac_get_desc(atchan);
1038 spin_unlock_irqrestore(lock: &atchan->lock, flags);
1039 if (!desc) {
1040 dev_err(chan2dev(chan), "can't get descriptor\n");
1041 return NULL;
1042 }
1043
1044 chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1045
1046 ublen = chunk->size >> dwidth;
1047
1048 desc->lld.mbr_sa = src;
1049 desc->lld.mbr_da = dst;
1050 desc->lld.mbr_sus = dmaengine_get_src_icg(xt, chunk);
1051 desc->lld.mbr_dus = dmaengine_get_dst_icg(xt, chunk);
1052
1053 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
1054 | AT_XDMAC_MBR_UBC_NDEN
1055 | AT_XDMAC_MBR_UBC_NSEN
1056 | ublen;
1057 desc->lld.mbr_cfg = chan_cc;
1058
1059 dev_dbg(chan2dev(chan),
1060 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1061 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da,
1062 desc->lld.mbr_ubc, desc->lld.mbr_cfg);
1063
1064 /* Chain lld. */
1065 if (prev)
1066 at_xdmac_queue_desc(chan, prev, desc);
1067
1068 return desc;
1069}
1070
1071static struct dma_async_tx_descriptor *
1072at_xdmac_prep_interleaved(struct dma_chan *chan,
1073 struct dma_interleaved_template *xt,
1074 unsigned long flags)
1075{
1076 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
1077 struct at_xdmac_desc *prev = NULL, *first = NULL;
1078 dma_addr_t dst_addr, src_addr;
1079 size_t src_skip = 0, dst_skip = 0, len = 0;
1080 struct data_chunk *chunk;
1081 int i;
1082
1083 if (!xt || !xt->numf || (xt->dir != DMA_MEM_TO_MEM))
1084 return NULL;
1085
1086 /*
1087 * TODO: Handle the case where we have to repeat a chain of
1088 * descriptors...
1089 */
1090 if ((xt->numf > 1) && (xt->frame_size > 1))
1091 return NULL;
1092
1093 dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, numf=%zu, frame_size=%zu, flags=0x%lx\n",
1094 __func__, &xt->src_start, &xt->dst_start, xt->numf,
1095 xt->frame_size, flags);
1096
1097 src_addr = xt->src_start;
1098 dst_addr = xt->dst_start;
1099
1100 if (xt->numf > 1) {
1101 first = at_xdmac_interleaved_queue_desc(chan, atchan,
1102 NULL,
1103 src: src_addr, dst: dst_addr,
1104 xt, chunk: xt->sgl);
1105 if (!first)
1106 return NULL;
1107
1108 /* Length of the block is (BLEN+1) microblocks. */
1109 for (i = 0; i < xt->numf - 1; i++)
1110 at_xdmac_increment_block_count(chan, desc: first);
1111
1112 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1113 __func__, first, first);
1114 list_add_tail(new: &first->desc_node, head: &first->descs_list);
1115 } else {
1116 for (i = 0; i < xt->frame_size; i++) {
1117 size_t src_icg = 0, dst_icg = 0;
1118 struct at_xdmac_desc *desc;
1119
1120 chunk = xt->sgl + i;
1121
1122 dst_icg = dmaengine_get_dst_icg(xt, chunk);
1123 src_icg = dmaengine_get_src_icg(xt, chunk);
1124
1125 src_skip = chunk->size + src_icg;
1126 dst_skip = chunk->size + dst_icg;
1127
1128 dev_dbg(chan2dev(chan),
1129 "%s: chunk size=%zu, src icg=%zu, dst icg=%zu\n",
1130 __func__, chunk->size, src_icg, dst_icg);
1131
1132 desc = at_xdmac_interleaved_queue_desc(chan, atchan,
1133 prev,
1134 src: src_addr, dst: dst_addr,
1135 xt, chunk);
1136 if (!desc) {
1137 if (first)
1138 list_splice_tail_init(list: &first->descs_list,
1139 head: &atchan->free_descs_list);
1140 return NULL;
1141 }
1142
1143 if (!first)
1144 first = desc;
1145
1146 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1147 __func__, desc, first);
1148 list_add_tail(new: &desc->desc_node, head: &first->descs_list);
1149
1150 if (xt->src_sgl)
1151 src_addr += src_skip;
1152
1153 if (xt->dst_sgl)
1154 dst_addr += dst_skip;
1155
1156 len += chunk->size;
1157 prev = desc;
1158 }
1159 }
1160
1161 first->tx_dma_desc.cookie = -EBUSY;
1162 first->tx_dma_desc.flags = flags;
1163 first->xfer_size = len;
1164
1165 return &first->tx_dma_desc;
1166}
1167
1168static struct dma_async_tx_descriptor *
1169at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
1170 size_t len, unsigned long flags)
1171{
1172 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
1173 struct at_xdmac_desc *first = NULL, *prev = NULL;
1174 size_t remaining_size = len, xfer_size = 0, ublen;
1175 dma_addr_t src_addr = src, dst_addr = dest;
1176 u32 dwidth;
1177 /*
1178 * WARNING: We don't know the direction, it involves we can't
1179 * dynamically set the source and dest interface so we have to use the
1180 * same one. Only interface 0 allows EBI access. Hopefully we can
1181 * access DDR through both ports (at least on SAMA5D4x), so we can use
1182 * the same interface for source and dest, that solves the fact we
1183 * don't know the direction.
1184 * ERRATA: Even if useless for memory transfers, the PERID has to not
1185 * match the one of another channel. If not, it could lead to spurious
1186 * flag status.
1187 * For SAMA7G5x case, the SIF and DIF fields are no longer used.
1188 * Thus, no need to have the SIF/DIF interfaces here.
1189 * For SAMA5D4x and SAMA5D2x the SIF and DIF are already configured as
1190 * zero.
1191 */
1192 u32 chan_cc = AT_XDMAC_CC_PERID(0x7f)
1193 | AT_XDMAC_CC_DAM_INCREMENTED_AM
1194 | AT_XDMAC_CC_SAM_INCREMENTED_AM
1195 | AT_XDMAC_CC_MBSIZE_SIXTEEN
1196 | AT_XDMAC_CC_TYPE_MEM_TRAN;
1197 unsigned long irqflags;
1198
1199 dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, len=%zd, flags=0x%lx\n",
1200 __func__, &src, &dest, len, flags);
1201
1202 if (unlikely(!len))
1203 return NULL;
1204
1205 dwidth = at_xdmac_align_width(chan, addr: src_addr | dst_addr);
1206
1207 /* Prepare descriptors. */
1208 while (remaining_size) {
1209 struct at_xdmac_desc *desc = NULL;
1210
1211 dev_dbg(chan2dev(chan), "%s: remaining_size=%zu\n", __func__, remaining_size);
1212
1213 spin_lock_irqsave(&atchan->lock, irqflags);
1214 desc = at_xdmac_get_desc(atchan);
1215 spin_unlock_irqrestore(lock: &atchan->lock, flags: irqflags);
1216 if (!desc) {
1217 dev_err(chan2dev(chan), "can't get descriptor\n");
1218 if (first)
1219 list_splice_tail_init(list: &first->descs_list,
1220 head: &atchan->free_descs_list);
1221 return NULL;
1222 }
1223
1224 /* Update src and dest addresses. */
1225 src_addr += xfer_size;
1226 dst_addr += xfer_size;
1227
1228 if (remaining_size >= AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)
1229 xfer_size = AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth;
1230 else
1231 xfer_size = remaining_size;
1232
1233 dev_dbg(chan2dev(chan), "%s: xfer_size=%zu\n", __func__, xfer_size);
1234
1235 /* Check remaining length and change data width if needed. */
1236 dwidth = at_xdmac_align_width(chan,
1237 addr: src_addr | dst_addr | xfer_size);
1238 chan_cc &= ~AT_XDMAC_CC_DWIDTH_MASK;
1239 chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1240
1241 ublen = xfer_size >> dwidth;
1242 remaining_size -= xfer_size;
1243
1244 desc->lld.mbr_sa = src_addr;
1245 desc->lld.mbr_da = dst_addr;
1246 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2
1247 | AT_XDMAC_MBR_UBC_NDEN
1248 | AT_XDMAC_MBR_UBC_NSEN
1249 | ublen;
1250 desc->lld.mbr_cfg = chan_cc;
1251
1252 dev_dbg(chan2dev(chan),
1253 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1254 __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc, desc->lld.mbr_cfg);
1255
1256 /* Chain lld. */
1257 if (prev)
1258 at_xdmac_queue_desc(chan, prev, desc);
1259
1260 prev = desc;
1261 if (!first)
1262 first = desc;
1263
1264 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
1265 __func__, desc, first);
1266 list_add_tail(new: &desc->desc_node, head: &first->descs_list);
1267 }
1268
1269 first->tx_dma_desc.flags = flags;
1270 first->xfer_size = len;
1271
1272 return &first->tx_dma_desc;
1273}
1274
1275static struct at_xdmac_desc *at_xdmac_memset_create_desc(struct dma_chan *chan,
1276 struct at_xdmac_chan *atchan,
1277 dma_addr_t dst_addr,
1278 size_t len,
1279 int value)
1280{
1281 struct at_xdmac_desc *desc;
1282 unsigned long flags;
1283 size_t ublen;
1284 u32 dwidth;
1285 char pattern;
1286 /*
1287 * WARNING: The channel configuration is set here since there is no
1288 * dmaengine_slave_config call in this case. Moreover we don't know the
1289 * direction, it involves we can't dynamically set the source and dest
1290 * interface so we have to use the same one. Only interface 0 allows EBI
1291 * access. Hopefully we can access DDR through both ports (at least on
1292 * SAMA5D4x), so we can use the same interface for source and dest,
1293 * that solves the fact we don't know the direction.
1294 * ERRATA: Even if useless for memory transfers, the PERID has to not
1295 * match the one of another channel. If not, it could lead to spurious
1296 * flag status.
1297 * For SAMA7G5x case, the SIF and DIF fields are no longer used.
1298 * Thus, no need to have the SIF/DIF interfaces here.
1299 * For SAMA5D4x and SAMA5D2x the SIF and DIF are already configured as
1300 * zero.
1301 */
1302 u32 chan_cc = AT_XDMAC_CC_PERID(0x7f)
1303 | AT_XDMAC_CC_DAM_UBS_AM
1304 | AT_XDMAC_CC_SAM_INCREMENTED_AM
1305 | AT_XDMAC_CC_MBSIZE_SIXTEEN
1306 | AT_XDMAC_CC_MEMSET_HW_MODE
1307 | AT_XDMAC_CC_TYPE_MEM_TRAN;
1308
1309 dwidth = at_xdmac_align_width(chan, addr: dst_addr);
1310
1311 if (len >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
1312 dev_err(chan2dev(chan),
1313 "%s: Transfer too large, aborting...\n",
1314 __func__);
1315 return NULL;
1316 }
1317
1318 spin_lock_irqsave(&atchan->lock, flags);
1319 desc = at_xdmac_get_desc(atchan);
1320 spin_unlock_irqrestore(lock: &atchan->lock, flags);
1321 if (!desc) {
1322 dev_err(chan2dev(chan), "can't get descriptor\n");
1323 return NULL;
1324 }
1325
1326 chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
1327
1328 /* Only the first byte of value is to be used according to dmaengine */
1329 pattern = (char)value;
1330
1331 ublen = len >> dwidth;
1332
1333 desc->lld.mbr_da = dst_addr;
1334 desc->lld.mbr_ds = (pattern << 24) |
1335 (pattern << 16) |
1336 (pattern << 8) |
1337 pattern;
1338 desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
1339 | AT_XDMAC_MBR_UBC_NDEN
1340 | AT_XDMAC_MBR_UBC_NSEN
1341 | ublen;
1342 desc->lld.mbr_cfg = chan_cc;
1343
1344 dev_dbg(chan2dev(chan),
1345 "%s: lld: mbr_da=%pad, mbr_ds=0x%08x, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
1346 __func__, &desc->lld.mbr_da, desc->lld.mbr_ds, desc->lld.mbr_ubc,
1347 desc->lld.mbr_cfg);
1348
1349 return desc;
1350}
1351
1352static struct dma_async_tx_descriptor *
1353at_xdmac_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value,
1354 size_t len, unsigned long flags)
1355{
1356 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
1357 struct at_xdmac_desc *desc;
1358
1359 dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%zu, pattern=0x%x, flags=0x%lx\n",
1360 __func__, &dest, len, value, flags);
1361
1362 if (unlikely(!len))
1363 return NULL;
1364
1365 desc = at_xdmac_memset_create_desc(chan, atchan, dst_addr: dest, len, value);
1366 list_add_tail(new: &desc->desc_node, head: &desc->descs_list);
1367
1368 desc->tx_dma_desc.cookie = -EBUSY;
1369 desc->tx_dma_desc.flags = flags;
1370 desc->xfer_size = len;
1371
1372 return &desc->tx_dma_desc;
1373}
1374
1375static struct dma_async_tx_descriptor *
1376at_xdmac_prep_dma_memset_sg(struct dma_chan *chan, struct scatterlist *sgl,
1377 unsigned int sg_len, int value,
1378 unsigned long flags)
1379{
1380 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
1381 struct at_xdmac_desc *desc, *pdesc = NULL,
1382 *ppdesc = NULL, *first = NULL;
1383 struct scatterlist *sg, *psg = NULL, *ppsg = NULL;
1384 size_t stride = 0, pstride = 0, len = 0;
1385 int i;
1386
1387 if (!sgl)
1388 return NULL;
1389
1390 dev_dbg(chan2dev(chan), "%s: sg_len=%d, value=0x%x, flags=0x%lx\n",
1391 __func__, sg_len, value, flags);
1392
1393 /* Prepare descriptors. */
1394 for_each_sg(sgl, sg, sg_len, i) {
1395 dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%d, pattern=0x%x, flags=0x%lx\n",
1396 __func__, &sg_dma_address(sg), sg_dma_len(sg),
1397 value, flags);
1398 desc = at_xdmac_memset_create_desc(chan, atchan,
1399 sg_dma_address(sg),
1400 sg_dma_len(sg),
1401 value);
1402 if (!desc && first)
1403 list_splice_tail_init(list: &first->descs_list,
1404 head: &atchan->free_descs_list);
1405
1406 if (!first)
1407 first = desc;
1408
1409 /* Update our strides */
1410 pstride = stride;
1411 if (psg)
1412 stride = sg_dma_address(sg) -
1413 (sg_dma_address(psg) + sg_dma_len(psg));
1414
1415 /*
1416 * The scatterlist API gives us only the address and
1417 * length of each elements.
1418 *
1419 * Unfortunately, we don't have the stride, which we
1420 * will need to compute.
1421 *
1422 * That make us end up in a situation like this one:
1423 * len stride len stride len
1424 * +-------+ +-------+ +-------+
1425 * | N-2 | | N-1 | | N |
1426 * +-------+ +-------+ +-------+
1427 *
1428 * We need all these three elements (N-2, N-1 and N)
1429 * to actually take the decision on whether we need to
1430 * queue N-1 or reuse N-2.
1431 *
1432 * We will only consider N if it is the last element.
1433 */
1434 if (ppdesc && pdesc) {
1435 if ((stride == pstride) &&
1436 (sg_dma_len(ppsg) == sg_dma_len(psg))) {
1437 dev_dbg(chan2dev(chan),
1438 "%s: desc 0x%p can be merged with desc 0x%p\n",
1439 __func__, pdesc, ppdesc);
1440
1441 /*
1442 * Increment the block count of the
1443 * N-2 descriptor
1444 */
1445 at_xdmac_increment_block_count(chan, desc: ppdesc);
1446 ppdesc->lld.mbr_dus = stride;
1447
1448 /*
1449 * Put back the N-1 descriptor in the
1450 * free descriptor list
1451 */
1452 list_add_tail(new: &pdesc->desc_node,
1453 head: &atchan->free_descs_list);
1454
1455 /*
1456 * Make our N-1 descriptor pointer
1457 * point to the N-2 since they were
1458 * actually merged.
1459 */
1460 pdesc = ppdesc;
1461
1462 /*
1463 * Rule out the case where we don't have
1464 * pstride computed yet (our second sg
1465 * element)
1466 *
1467 * We also want to catch the case where there
1468 * would be a negative stride,
1469 */
1470 } else if (pstride ||
1471 sg_dma_address(sg) < sg_dma_address(psg)) {
1472 /*
1473 * Queue the N-1 descriptor after the
1474 * N-2
1475 */
1476 at_xdmac_queue_desc(chan, prev: ppdesc, desc: pdesc);
1477
1478 /*
1479 * Add the N-1 descriptor to the list
1480 * of the descriptors used for this
1481 * transfer
1482 */
1483 list_add_tail(new: &desc->desc_node,
1484 head: &first->descs_list);
1485 dev_dbg(chan2dev(chan),
1486 "%s: add desc 0x%p to descs_list 0x%p\n",
1487 __func__, desc, first);
1488 }
1489 }
1490
1491 /*
1492 * If we are the last element, just see if we have the
1493 * same size than the previous element.
1494 *
1495 * If so, we can merge it with the previous descriptor
1496 * since we don't care about the stride anymore.
1497 */
1498 if ((i == (sg_len - 1)) &&
1499 sg_dma_len(psg) == sg_dma_len(sg)) {
1500 dev_dbg(chan2dev(chan),
1501 "%s: desc 0x%p can be merged with desc 0x%p\n",
1502 __func__, desc, pdesc);
1503
1504 /*
1505 * Increment the block count of the N-1
1506 * descriptor
1507 */
1508 at_xdmac_increment_block_count(chan, desc: pdesc);
1509 pdesc->lld.mbr_dus = stride;
1510
1511 /*
1512 * Put back the N descriptor in the free
1513 * descriptor list
1514 */
1515 list_add_tail(new: &desc->desc_node,
1516 head: &atchan->free_descs_list);
1517 }
1518
1519 /* Update our descriptors */
1520 ppdesc = pdesc;
1521 pdesc = desc;
1522
1523 /* Update our scatter pointers */
1524 ppsg = psg;
1525 psg = sg;
1526
1527 len += sg_dma_len(sg);
1528 }
1529
1530 first->tx_dma_desc.cookie = -EBUSY;
1531 first->tx_dma_desc.flags = flags;
1532 first->xfer_size = len;
1533
1534 return &first->tx_dma_desc;
1535}
1536
1537static enum dma_status
1538at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
1539 struct dma_tx_state *txstate)
1540{
1541 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
1542 struct at_xdmac *atxdmac = to_at_xdmac(ddev: atchan->chan.device);
1543 struct at_xdmac_desc *desc, *_desc, *iter;
1544 struct list_head *descs_list;
1545 enum dma_status ret;
1546 int residue, retry, pm_status;
1547 u32 cur_nda, check_nda, cur_ubc, mask, value;
1548 u8 dwidth = 0;
1549 unsigned long flags;
1550 bool initd;
1551
1552 ret = dma_cookie_status(chan, cookie, state: txstate);
1553 if (ret == DMA_COMPLETE || !txstate)
1554 return ret;
1555
1556 pm_status = pm_runtime_resume_and_get(dev: atxdmac->dev);
1557 if (pm_status < 0)
1558 return DMA_ERROR;
1559
1560 spin_lock_irqsave(&atchan->lock, flags);
1561
1562 desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node);
1563
1564 /*
1565 * If the transfer has not been started yet, don't need to compute the
1566 * residue, it's the transfer length.
1567 */
1568 if (!desc->active_xfer) {
1569 dma_set_residue(state: txstate, residue: desc->xfer_size);
1570 goto spin_unlock;
1571 }
1572
1573 residue = desc->xfer_size;
1574 /*
1575 * Flush FIFO: only relevant when the transfer is source peripheral
1576 * synchronized. Flush is needed before reading CUBC because data in
1577 * the FIFO are not reported by CUBC. Reporting a residue of the
1578 * transfer length while we have data in FIFO can cause issue.
1579 * Usecase: atmel USART has a timeout which means I have received
1580 * characters but there is no more character received for a while. On
1581 * timeout, it requests the residue. If the data are in the DMA FIFO,
1582 * we will return a residue of the transfer length. It means no data
1583 * received. If an application is waiting for these data, it will hang
1584 * since we won't have another USART timeout without receiving new
1585 * data.
1586 */
1587 mask = AT_XDMAC_CC_TYPE | AT_XDMAC_CC_DSYNC;
1588 value = AT_XDMAC_CC_TYPE_PER_TRAN | AT_XDMAC_CC_DSYNC_PER2MEM;
1589 if ((desc->lld.mbr_cfg & mask) == value) {
1590 at_xdmac_write(atxdmac, atxdmac->layout->gswf, atchan->mask);
1591 while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS))
1592 cpu_relax();
1593 }
1594
1595 /*
1596 * The easiest way to compute the residue should be to pause the DMA
1597 * but doing this can lead to miss some data as some devices don't
1598 * have FIFO.
1599 * We need to read several registers because:
1600 * - DMA is running therefore a descriptor change is possible while
1601 * reading these registers
1602 * - When the block transfer is done, the value of the CUBC register
1603 * is set to its initial value until the fetch of the next descriptor.
1604 * This value will corrupt the residue calculation so we have to skip
1605 * it.
1606 *
1607 * INITD -------- ------------
1608 * |____________________|
1609 * _______________________ _______________
1610 * NDA @desc2 \/ @desc3
1611 * _______________________/\_______________
1612 * __________ ___________ _______________
1613 * CUBC 0 \/ MAX desc1 \/ MAX desc2
1614 * __________/\___________/\_______________
1615 *
1616 * Since descriptors are aligned on 64 bits, we can assume that
1617 * the update of NDA and CUBC is atomic.
1618 * Memory barriers are used to ensure the read order of the registers.
1619 * A max number of retries is set because unlikely it could never ends.
1620 */
1621 for (retry = 0; retry < AT_XDMAC_RESIDUE_MAX_RETRIES; retry++) {
1622 check_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
1623 rmb();
1624 cur_ubc = at_xdmac_chan_read(atchan, AT_XDMAC_CUBC);
1625 rmb();
1626 initd = !!(at_xdmac_chan_read(atchan, AT_XDMAC_CC) & AT_XDMAC_CC_INITD);
1627 rmb();
1628 cur_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
1629 rmb();
1630
1631 if ((check_nda == cur_nda) && initd)
1632 break;
1633 }
1634
1635 if (unlikely(retry >= AT_XDMAC_RESIDUE_MAX_RETRIES)) {
1636 ret = DMA_ERROR;
1637 goto spin_unlock;
1638 }
1639
1640 /*
1641 * Flush FIFO: only relevant when the transfer is source peripheral
1642 * synchronized. Another flush is needed here because CUBC is updated
1643 * when the controller sends the data write command. It can lead to
1644 * report data that are not written in the memory or the device. The
1645 * FIFO flush ensures that data are really written.
1646 */
1647 if ((desc->lld.mbr_cfg & mask) == value) {
1648 at_xdmac_write(atxdmac, atxdmac->layout->gswf, atchan->mask);
1649 while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS))
1650 cpu_relax();
1651 }
1652
1653 /*
1654 * Remove size of all microblocks already transferred and the current
1655 * one. Then add the remaining size to transfer of the current
1656 * microblock.
1657 */
1658 descs_list = &desc->descs_list;
1659 list_for_each_entry_safe(iter, _desc, descs_list, desc_node) {
1660 dwidth = at_xdmac_get_dwidth(cfg: iter->lld.mbr_cfg);
1661 residue -= (iter->lld.mbr_ubc & 0xffffff) << dwidth;
1662 if ((iter->lld.mbr_nda & 0xfffffffc) == cur_nda) {
1663 desc = iter;
1664 break;
1665 }
1666 }
1667 residue += cur_ubc << dwidth;
1668
1669 dma_set_residue(state: txstate, residue);
1670
1671 dev_dbg(chan2dev(chan),
1672 "%s: desc=0x%p, tx_dma_desc.phys=%pad, tx_status=%d, cookie=%d, residue=%d\n",
1673 __func__, desc, &desc->tx_dma_desc.phys, ret, cookie, residue);
1674
1675spin_unlock:
1676 spin_unlock_irqrestore(lock: &atchan->lock, flags);
1677 pm_runtime_mark_last_busy(dev: atxdmac->dev);
1678 pm_runtime_put_autosuspend(dev: atxdmac->dev);
1679 return ret;
1680}
1681
1682static void at_xdmac_advance_work(struct at_xdmac_chan *atchan)
1683{
1684 struct at_xdmac_desc *desc;
1685
1686 /*
1687 * If channel is enabled, do nothing, advance_work will be triggered
1688 * after the interruption.
1689 */
1690 if (at_xdmac_chan_is_enabled(atchan) || list_empty(head: &atchan->xfers_list))
1691 return;
1692
1693 desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc,
1694 xfer_node);
1695 dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1696 if (!desc->active_xfer)
1697 at_xdmac_start_xfer(atchan, first: desc);
1698}
1699
1700static void at_xdmac_handle_cyclic(struct at_xdmac_chan *atchan)
1701{
1702 struct at_xdmac_desc *desc;
1703 struct dma_async_tx_descriptor *txd;
1704
1705 spin_lock_irq(lock: &atchan->lock);
1706 dev_dbg(chan2dev(&atchan->chan), "%s: status=0x%08x\n",
1707 __func__, atchan->irq_status);
1708 if (list_empty(head: &atchan->xfers_list)) {
1709 spin_unlock_irq(lock: &atchan->lock);
1710 return;
1711 }
1712 desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc,
1713 xfer_node);
1714 spin_unlock_irq(lock: &atchan->lock);
1715 txd = &desc->tx_dma_desc;
1716 if (txd->flags & DMA_PREP_INTERRUPT)
1717 dmaengine_desc_get_callback_invoke(tx: txd, NULL);
1718}
1719
1720/* Called with atchan->lock held. */
1721static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)
1722{
1723 struct at_xdmac *atxdmac = to_at_xdmac(ddev: atchan->chan.device);
1724 struct at_xdmac_desc *bad_desc;
1725 int ret;
1726
1727 ret = pm_runtime_resume_and_get(dev: atxdmac->dev);
1728 if (ret < 0)
1729 return;
1730
1731 /*
1732 * The descriptor currently at the head of the active list is
1733 * broken. Since we don't have any way to report errors, we'll
1734 * just have to scream loudly and try to continue with other
1735 * descriptors queued (if any).
1736 */
1737 if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
1738 dev_err(chan2dev(&atchan->chan), "read bus error!!!");
1739 if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
1740 dev_err(chan2dev(&atchan->chan), "write bus error!!!");
1741 if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
1742 dev_err(chan2dev(&atchan->chan), "request overflow error!!!");
1743
1744 /* Channel must be disabled first as it's not done automatically */
1745 at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1746 while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
1747 cpu_relax();
1748
1749 bad_desc = list_first_entry(&atchan->xfers_list,
1750 struct at_xdmac_desc,
1751 xfer_node);
1752
1753 /* Print bad descriptor's details if needed */
1754 dev_dbg(chan2dev(&atchan->chan),
1755 "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
1756 __func__, &bad_desc->lld.mbr_sa, &bad_desc->lld.mbr_da,
1757 bad_desc->lld.mbr_ubc);
1758
1759 pm_runtime_mark_last_busy(dev: atxdmac->dev);
1760 pm_runtime_put_autosuspend(dev: atxdmac->dev);
1761
1762 /* Then continue with usual descriptor management */
1763}
1764
1765static void at_xdmac_tasklet(struct tasklet_struct *t)
1766{
1767 struct at_xdmac_chan *atchan = from_tasklet(atchan, t, tasklet);
1768 struct at_xdmac *atxdmac = to_at_xdmac(ddev: atchan->chan.device);
1769 struct at_xdmac_desc *desc;
1770 struct dma_async_tx_descriptor *txd;
1771 u32 error_mask;
1772
1773 if (at_xdmac_chan_is_cyclic(atchan))
1774 return at_xdmac_handle_cyclic(atchan);
1775
1776 error_mask = AT_XDMAC_CIS_RBEIS | AT_XDMAC_CIS_WBEIS |
1777 AT_XDMAC_CIS_ROIS;
1778
1779 spin_lock_irq(lock: &atchan->lock);
1780
1781 dev_dbg(chan2dev(&atchan->chan), "%s: status=0x%08x\n",
1782 __func__, atchan->irq_status);
1783
1784 if (!(atchan->irq_status & AT_XDMAC_CIS_LIS) &&
1785 !(atchan->irq_status & error_mask)) {
1786 spin_unlock_irq(lock: &atchan->lock);
1787 return;
1788 }
1789
1790 if (atchan->irq_status & error_mask)
1791 at_xdmac_handle_error(atchan);
1792
1793 desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc,
1794 xfer_node);
1795 dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
1796 if (!desc->active_xfer) {
1797 dev_err(chan2dev(&atchan->chan), "Xfer not active: exiting");
1798 spin_unlock_irq(lock: &atchan->lock);
1799 return;
1800 }
1801
1802 txd = &desc->tx_dma_desc;
1803 dma_cookie_complete(tx: txd);
1804 /* Remove the transfer from the transfer list. */
1805 list_del(entry: &desc->xfer_node);
1806 spin_unlock_irq(lock: &atchan->lock);
1807
1808 if (txd->flags & DMA_PREP_INTERRUPT)
1809 dmaengine_desc_get_callback_invoke(tx: txd, NULL);
1810
1811 dma_run_dependencies(tx: txd);
1812
1813 spin_lock_irq(lock: &atchan->lock);
1814 /* Move the xfer descriptors into the free descriptors list. */
1815 list_splice_tail_init(list: &desc->descs_list, head: &atchan->free_descs_list);
1816 at_xdmac_advance_work(atchan);
1817 spin_unlock_irq(lock: &atchan->lock);
1818
1819 /*
1820 * Decrement runtime PM ref counter incremented in
1821 * at_xdmac_start_xfer().
1822 */
1823 pm_runtime_mark_last_busy(dev: atxdmac->dev);
1824 pm_runtime_put_autosuspend(dev: atxdmac->dev);
1825}
1826
1827static irqreturn_t at_xdmac_interrupt(int irq, void *dev_id)
1828{
1829 struct at_xdmac *atxdmac = (struct at_xdmac *)dev_id;
1830 struct at_xdmac_chan *atchan;
1831 u32 imr, status, pending;
1832 u32 chan_imr, chan_status;
1833 int i, ret = IRQ_NONE;
1834
1835 do {
1836 imr = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
1837 status = at_xdmac_read(atxdmac, AT_XDMAC_GIS);
1838 pending = status & imr;
1839
1840 dev_vdbg(atxdmac->dma.dev,
1841 "%s: status=0x%08x, imr=0x%08x, pending=0x%08x\n",
1842 __func__, status, imr, pending);
1843
1844 if (!pending)
1845 break;
1846
1847 /* We have to find which channel has generated the interrupt. */
1848 for (i = 0; i < atxdmac->dma.chancnt; i++) {
1849 if (!((1 << i) & pending))
1850 continue;
1851
1852 atchan = &atxdmac->chan[i];
1853 chan_imr = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
1854 chan_status = at_xdmac_chan_read(atchan, AT_XDMAC_CIS);
1855 atchan->irq_status = chan_status & chan_imr;
1856 dev_vdbg(atxdmac->dma.dev,
1857 "%s: chan%d: imr=0x%x, status=0x%x\n",
1858 __func__, i, chan_imr, chan_status);
1859 dev_vdbg(chan2dev(&atchan->chan),
1860 "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
1861 __func__,
1862 at_xdmac_chan_read(atchan, AT_XDMAC_CC),
1863 at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
1864 at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
1865 at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
1866 at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
1867 at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
1868
1869 if (atchan->irq_status & (AT_XDMAC_CIS_RBEIS | AT_XDMAC_CIS_WBEIS))
1870 at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
1871
1872 tasklet_schedule(t: &atchan->tasklet);
1873 ret = IRQ_HANDLED;
1874 }
1875
1876 } while (pending);
1877
1878 return ret;
1879}
1880
1881static void at_xdmac_issue_pending(struct dma_chan *chan)
1882{
1883 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
1884 unsigned long flags;
1885
1886 dev_dbg(chan2dev(&atchan->chan), "%s\n", __func__);
1887
1888 spin_lock_irqsave(&atchan->lock, flags);
1889 at_xdmac_advance_work(atchan);
1890 spin_unlock_irqrestore(lock: &atchan->lock, flags);
1891
1892 return;
1893}
1894
1895static int at_xdmac_device_config(struct dma_chan *chan,
1896 struct dma_slave_config *config)
1897{
1898 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
1899 int ret;
1900 unsigned long flags;
1901
1902 dev_dbg(chan2dev(chan), "%s\n", __func__);
1903
1904 spin_lock_irqsave(&atchan->lock, flags);
1905 ret = at_xdmac_set_slave_config(chan, sconfig: config);
1906 spin_unlock_irqrestore(lock: &atchan->lock, flags);
1907
1908 return ret;
1909}
1910
1911static void at_xdmac_device_pause_set(struct at_xdmac *atxdmac,
1912 struct at_xdmac_chan *atchan)
1913{
1914 at_xdmac_write(atxdmac, atxdmac->layout->grws, atchan->mask);
1915 while (at_xdmac_chan_read(atchan, AT_XDMAC_CC) &
1916 (AT_XDMAC_CC_WRIP | AT_XDMAC_CC_RDIP))
1917 cpu_relax();
1918}
1919
1920static void at_xdmac_device_pause_internal(struct at_xdmac_chan *atchan)
1921{
1922 struct at_xdmac *atxdmac = to_at_xdmac(ddev: atchan->chan.device);
1923 unsigned long flags;
1924
1925 spin_lock_irqsave(&atchan->lock, flags);
1926 set_bit(nr: AT_XDMAC_CHAN_IS_PAUSED_INTERNAL, addr: &atchan->status);
1927 at_xdmac_device_pause_set(atxdmac, atchan);
1928 spin_unlock_irqrestore(lock: &atchan->lock, flags);
1929}
1930
1931static int at_xdmac_device_pause(struct dma_chan *chan)
1932{
1933 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
1934 struct at_xdmac *atxdmac = to_at_xdmac(ddev: atchan->chan.device);
1935 unsigned long flags;
1936 int ret;
1937
1938 dev_dbg(chan2dev(chan), "%s\n", __func__);
1939
1940 if (test_and_set_bit(nr: AT_XDMAC_CHAN_IS_PAUSED, addr: &atchan->status))
1941 return 0;
1942
1943 ret = pm_runtime_resume_and_get(dev: atxdmac->dev);
1944 if (ret < 0)
1945 return ret;
1946
1947 spin_lock_irqsave(&atchan->lock, flags);
1948
1949 at_xdmac_device_pause_set(atxdmac, atchan);
1950 /* Decrement runtime PM ref counter for each active descriptor. */
1951 at_xdmac_runtime_suspend_descriptors(atchan);
1952
1953 spin_unlock_irqrestore(lock: &atchan->lock, flags);
1954
1955 pm_runtime_mark_last_busy(dev: atxdmac->dev);
1956 pm_runtime_put_autosuspend(dev: atxdmac->dev);
1957
1958 return 0;
1959}
1960
1961static void at_xdmac_device_resume_internal(struct at_xdmac_chan *atchan)
1962{
1963 struct at_xdmac *atxdmac = to_at_xdmac(ddev: atchan->chan.device);
1964 unsigned long flags;
1965
1966 spin_lock_irqsave(&atchan->lock, flags);
1967 at_xdmac_write(atxdmac, atxdmac->layout->grwr, atchan->mask);
1968 clear_bit(nr: AT_XDMAC_CHAN_IS_PAUSED_INTERNAL, addr: &atchan->status);
1969 spin_unlock_irqrestore(lock: &atchan->lock, flags);
1970}
1971
1972static int at_xdmac_device_resume(struct dma_chan *chan)
1973{
1974 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
1975 struct at_xdmac *atxdmac = to_at_xdmac(ddev: atchan->chan.device);
1976 unsigned long flags;
1977 int ret;
1978
1979 dev_dbg(chan2dev(chan), "%s\n", __func__);
1980
1981 ret = pm_runtime_resume_and_get(dev: atxdmac->dev);
1982 if (ret < 0)
1983 return ret;
1984
1985 spin_lock_irqsave(&atchan->lock, flags);
1986 if (!at_xdmac_chan_is_paused(atchan))
1987 goto unlock;
1988
1989 /* Increment runtime PM ref counter for each active descriptor. */
1990 ret = at_xdmac_runtime_resume_descriptors(atchan);
1991 if (ret < 0)
1992 goto unlock;
1993
1994 at_xdmac_write(atxdmac, atxdmac->layout->grwr, atchan->mask);
1995 clear_bit(nr: AT_XDMAC_CHAN_IS_PAUSED, addr: &atchan->status);
1996
1997unlock:
1998 spin_unlock_irqrestore(lock: &atchan->lock, flags);
1999 pm_runtime_mark_last_busy(dev: atxdmac->dev);
2000 pm_runtime_put_autosuspend(dev: atxdmac->dev);
2001
2002 return ret;
2003}
2004
2005static int at_xdmac_device_terminate_all(struct dma_chan *chan)
2006{
2007 struct at_xdmac_desc *desc, *_desc;
2008 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
2009 struct at_xdmac *atxdmac = to_at_xdmac(ddev: atchan->chan.device);
2010 unsigned long flags;
2011 int ret;
2012
2013 dev_dbg(chan2dev(chan), "%s\n", __func__);
2014
2015 ret = pm_runtime_resume_and_get(dev: atxdmac->dev);
2016 if (ret < 0)
2017 return ret;
2018
2019 spin_lock_irqsave(&atchan->lock, flags);
2020 at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
2021 while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
2022 cpu_relax();
2023
2024 /* Cancel all pending transfers. */
2025 list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node) {
2026 list_del(entry: &desc->xfer_node);
2027 list_splice_tail_init(list: &desc->descs_list,
2028 head: &atchan->free_descs_list);
2029 /*
2030 * We incremented the runtime PM reference count on
2031 * at_xdmac_start_xfer() for this descriptor. Now it's time
2032 * to release it.
2033 */
2034 if (desc->active_xfer) {
2035 pm_runtime_put_autosuspend(dev: atxdmac->dev);
2036 pm_runtime_mark_last_busy(dev: atxdmac->dev);
2037 }
2038 }
2039
2040 clear_bit(nr: AT_XDMAC_CHAN_IS_PAUSED, addr: &atchan->status);
2041 clear_bit(nr: AT_XDMAC_CHAN_IS_CYCLIC, addr: &atchan->status);
2042 spin_unlock_irqrestore(lock: &atchan->lock, flags);
2043
2044 pm_runtime_mark_last_busy(dev: atxdmac->dev);
2045 pm_runtime_put_autosuspend(dev: atxdmac->dev);
2046
2047 return 0;
2048}
2049
2050static int at_xdmac_alloc_chan_resources(struct dma_chan *chan)
2051{
2052 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
2053 struct at_xdmac_desc *desc;
2054 int i;
2055
2056 if (at_xdmac_chan_is_enabled(atchan)) {
2057 dev_err(chan2dev(chan),
2058 "can't allocate channel resources (channel enabled)\n");
2059 return -EIO;
2060 }
2061
2062 if (!list_empty(head: &atchan->free_descs_list)) {
2063 dev_err(chan2dev(chan),
2064 "can't allocate channel resources (channel not free from a previous use)\n");
2065 return -EIO;
2066 }
2067
2068 for (i = 0; i < init_nr_desc_per_channel; i++) {
2069 desc = at_xdmac_alloc_desc(chan, GFP_KERNEL);
2070 if (!desc) {
2071 if (i == 0) {
2072 dev_warn(chan2dev(chan),
2073 "can't allocate any descriptors\n");
2074 return -EIO;
2075 }
2076 dev_warn(chan2dev(chan),
2077 "only %d descriptors have been allocated\n", i);
2078 break;
2079 }
2080 list_add_tail(new: &desc->desc_node, head: &atchan->free_descs_list);
2081 }
2082
2083 dma_cookie_init(chan);
2084
2085 dev_dbg(chan2dev(chan), "%s: allocated %d descriptors\n", __func__, i);
2086
2087 return i;
2088}
2089
2090static void at_xdmac_free_chan_resources(struct dma_chan *chan)
2091{
2092 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
2093 struct at_xdmac *atxdmac = to_at_xdmac(ddev: chan->device);
2094 struct at_xdmac_desc *desc, *_desc;
2095
2096 list_for_each_entry_safe(desc, _desc, &atchan->free_descs_list, desc_node) {
2097 dev_dbg(chan2dev(chan), "%s: freeing descriptor %p\n", __func__, desc);
2098 list_del(entry: &desc->desc_node);
2099 dma_pool_free(pool: atxdmac->at_xdmac_desc_pool, vaddr: desc, addr: desc->tx_dma_desc.phys);
2100 }
2101
2102 return;
2103}
2104
2105static void at_xdmac_axi_config(struct platform_device *pdev)
2106{
2107 struct at_xdmac *atxdmac = (struct at_xdmac *)platform_get_drvdata(pdev);
2108 bool dev_m2m = false;
2109 u32 dma_requests;
2110
2111 if (!atxdmac->layout->axi_config)
2112 return; /* Not supported */
2113
2114 if (!of_property_read_u32(np: pdev->dev.of_node, propname: "dma-requests",
2115 out_value: &dma_requests)) {
2116 dev_info(&pdev->dev, "controller in mem2mem mode.\n");
2117 dev_m2m = true;
2118 }
2119
2120 if (dev_m2m) {
2121 at_xdmac_write(atxdmac, AT_XDMAC_GCFG, AT_XDMAC_GCFG_M2M);
2122 at_xdmac_write(atxdmac, AT_XDMAC_GWAC, AT_XDMAC_GWAC_M2M);
2123 } else {
2124 at_xdmac_write(atxdmac, AT_XDMAC_GCFG, AT_XDMAC_GCFG_P2M);
2125 at_xdmac_write(atxdmac, AT_XDMAC_GWAC, AT_XDMAC_GWAC_P2M);
2126 }
2127}
2128
2129static int __maybe_unused atmel_xdmac_prepare(struct device *dev)
2130{
2131 struct at_xdmac *atxdmac = dev_get_drvdata(dev);
2132 struct dma_chan *chan, *_chan;
2133
2134 list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
2135 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
2136
2137 /* Wait for transfer completion, except in cyclic case. */
2138 if (at_xdmac_chan_is_enabled(atchan) && !at_xdmac_chan_is_cyclic(atchan))
2139 return -EAGAIN;
2140 }
2141 return 0;
2142}
2143
2144static int __maybe_unused atmel_xdmac_suspend(struct device *dev)
2145{
2146 struct at_xdmac *atxdmac = dev_get_drvdata(dev);
2147 struct dma_chan *chan, *_chan;
2148 int ret;
2149
2150 ret = pm_runtime_resume_and_get(dev: atxdmac->dev);
2151 if (ret < 0)
2152 return ret;
2153
2154 list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
2155 struct at_xdmac_chan *atchan = to_at_xdmac_chan(dchan: chan);
2156
2157 atchan->save_cc = at_xdmac_chan_read(atchan, AT_XDMAC_CC);
2158 if (at_xdmac_chan_is_cyclic(atchan)) {
2159 if (!at_xdmac_chan_is_paused(atchan)) {
2160 dev_warn(chan2dev(chan), "%s: channel %d not paused\n",
2161 __func__, chan->chan_id);
2162 at_xdmac_device_pause_internal(atchan);
2163 at_xdmac_runtime_suspend_descriptors(atchan);
2164 }
2165 atchan->save_cim = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
2166 atchan->save_cnda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA);
2167 atchan->save_cndc = at_xdmac_chan_read(atchan, AT_XDMAC_CNDC);
2168 }
2169 }
2170 atxdmac->save_gim = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
2171 atxdmac->save_gs = at_xdmac_read(atxdmac, AT_XDMAC_GS);
2172
2173 at_xdmac_off(atxdmac, suspend_descriptors: false);
2174 pm_runtime_mark_last_busy(dev: atxdmac->dev);
2175 pm_runtime_put_noidle(dev: atxdmac->dev);
2176 clk_disable_unprepare(clk: atxdmac->clk);
2177
2178 return 0;
2179}
2180
2181static int __maybe_unused atmel_xdmac_resume(struct device *dev)
2182{
2183 struct at_xdmac *atxdmac = dev_get_drvdata(dev);
2184 struct at_xdmac_chan *atchan;
2185 struct dma_chan *chan, *_chan;
2186 struct platform_device *pdev = container_of(dev, struct platform_device, dev);
2187 int i, ret;
2188
2189 ret = clk_prepare_enable(clk: atxdmac->clk);
2190 if (ret)
2191 return ret;
2192
2193 pm_runtime_get_noresume(dev: atxdmac->dev);
2194
2195 at_xdmac_axi_config(pdev);
2196
2197 /* Clear pending interrupts. */
2198 for (i = 0; i < atxdmac->dma.chancnt; i++) {
2199 atchan = &atxdmac->chan[i];
2200 while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
2201 cpu_relax();
2202 }
2203
2204 at_xdmac_write(atxdmac, AT_XDMAC_GIE, atxdmac->save_gim);
2205 list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
2206 atchan = to_at_xdmac_chan(dchan: chan);
2207
2208 at_xdmac_chan_write(atchan, AT_XDMAC_CC, atchan->save_cc);
2209 if (at_xdmac_chan_is_cyclic(atchan)) {
2210 /*
2211 * Resume only channels not explicitly paused by
2212 * consumers.
2213 */
2214 if (at_xdmac_chan_is_paused_internal(atchan)) {
2215 ret = at_xdmac_runtime_resume_descriptors(atchan);
2216 if (ret < 0)
2217 return ret;
2218 at_xdmac_device_resume_internal(atchan);
2219 }
2220
2221 /*
2222 * We may resume from a deep sleep state where power
2223 * to DMA controller is cut-off. Thus, restore the
2224 * suspend state of channels set though dmaengine API.
2225 */
2226 else if (at_xdmac_chan_is_paused(atchan))
2227 at_xdmac_device_pause_set(atxdmac, atchan);
2228
2229 at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, atchan->save_cnda);
2230 at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, atchan->save_cndc);
2231 at_xdmac_chan_write(atchan, AT_XDMAC_CIE, atchan->save_cim);
2232 wmb();
2233 if (atxdmac->save_gs & atchan->mask)
2234 at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
2235 }
2236 }
2237
2238 pm_runtime_mark_last_busy(dev: atxdmac->dev);
2239 pm_runtime_put_autosuspend(dev: atxdmac->dev);
2240
2241 return 0;
2242}
2243
2244static int __maybe_unused atmel_xdmac_runtime_suspend(struct device *dev)
2245{
2246 struct at_xdmac *atxdmac = dev_get_drvdata(dev);
2247
2248 clk_disable(clk: atxdmac->clk);
2249
2250 return 0;
2251}
2252
2253static int __maybe_unused atmel_xdmac_runtime_resume(struct device *dev)
2254{
2255 struct at_xdmac *atxdmac = dev_get_drvdata(dev);
2256
2257 return clk_enable(clk: atxdmac->clk);
2258}
2259
2260static int at_xdmac_probe(struct platform_device *pdev)
2261{
2262 struct at_xdmac *atxdmac;
2263 int irq, nr_channels, i, ret;
2264 void __iomem *base;
2265 u32 reg;
2266
2267 irq = platform_get_irq(pdev, 0);
2268 if (irq < 0)
2269 return irq;
2270
2271 base = devm_platform_ioremap_resource(pdev, index: 0);
2272 if (IS_ERR(ptr: base))
2273 return PTR_ERR(ptr: base);
2274
2275 /*
2276 * Read number of xdmac channels, read helper function can't be used
2277 * since atxdmac is not yet allocated and we need to know the number
2278 * of channels to do the allocation.
2279 */
2280 reg = readl_relaxed(base + AT_XDMAC_GTYPE);
2281 nr_channels = AT_XDMAC_NB_CH(reg);
2282 if (nr_channels > AT_XDMAC_MAX_CHAN) {
2283 dev_err(&pdev->dev, "invalid number of channels (%u)\n",
2284 nr_channels);
2285 return -EINVAL;
2286 }
2287
2288 atxdmac = devm_kzalloc(dev: &pdev->dev,
2289 struct_size(atxdmac, chan, nr_channels),
2290 GFP_KERNEL);
2291 if (!atxdmac) {
2292 dev_err(&pdev->dev, "can't allocate at_xdmac structure\n");
2293 return -ENOMEM;
2294 }
2295
2296 atxdmac->regs = base;
2297 atxdmac->irq = irq;
2298 atxdmac->dev = &pdev->dev;
2299
2300 atxdmac->layout = of_device_get_match_data(dev: &pdev->dev);
2301 if (!atxdmac->layout)
2302 return -ENODEV;
2303
2304 atxdmac->clk = devm_clk_get(dev: &pdev->dev, id: "dma_clk");
2305 if (IS_ERR(ptr: atxdmac->clk)) {
2306 dev_err(&pdev->dev, "can't get dma_clk\n");
2307 return PTR_ERR(ptr: atxdmac->clk);
2308 }
2309
2310 /* Do not use dev res to prevent races with tasklet */
2311 ret = request_irq(irq: atxdmac->irq, handler: at_xdmac_interrupt, flags: 0, name: "at_xdmac", dev: atxdmac);
2312 if (ret) {
2313 dev_err(&pdev->dev, "can't request irq\n");
2314 return ret;
2315 }
2316
2317 ret = clk_prepare_enable(clk: atxdmac->clk);
2318 if (ret) {
2319 dev_err(&pdev->dev, "can't prepare or enable clock\n");
2320 goto err_free_irq;
2321 }
2322
2323 atxdmac->at_xdmac_desc_pool =
2324 dmam_pool_create(name: dev_name(dev: &pdev->dev), dev: &pdev->dev,
2325 size: sizeof(struct at_xdmac_desc), align: 4, allocation: 0);
2326 if (!atxdmac->at_xdmac_desc_pool) {
2327 dev_err(&pdev->dev, "no memory for descriptors dma pool\n");
2328 ret = -ENOMEM;
2329 goto err_clk_disable;
2330 }
2331
2332 dma_cap_set(DMA_CYCLIC, atxdmac->dma.cap_mask);
2333 dma_cap_set(DMA_INTERLEAVE, atxdmac->dma.cap_mask);
2334 dma_cap_set(DMA_MEMCPY, atxdmac->dma.cap_mask);
2335 dma_cap_set(DMA_MEMSET, atxdmac->dma.cap_mask);
2336 dma_cap_set(DMA_MEMSET_SG, atxdmac->dma.cap_mask);
2337 dma_cap_set(DMA_SLAVE, atxdmac->dma.cap_mask);
2338 /*
2339 * Without DMA_PRIVATE the driver is not able to allocate more than
2340 * one channel, second allocation fails in private_candidate.
2341 */
2342 dma_cap_set(DMA_PRIVATE, atxdmac->dma.cap_mask);
2343 atxdmac->dma.dev = &pdev->dev;
2344 atxdmac->dma.device_alloc_chan_resources = at_xdmac_alloc_chan_resources;
2345 atxdmac->dma.device_free_chan_resources = at_xdmac_free_chan_resources;
2346 atxdmac->dma.device_tx_status = at_xdmac_tx_status;
2347 atxdmac->dma.device_issue_pending = at_xdmac_issue_pending;
2348 atxdmac->dma.device_prep_dma_cyclic = at_xdmac_prep_dma_cyclic;
2349 atxdmac->dma.device_prep_interleaved_dma = at_xdmac_prep_interleaved;
2350 atxdmac->dma.device_prep_dma_memcpy = at_xdmac_prep_dma_memcpy;
2351 atxdmac->dma.device_prep_dma_memset = at_xdmac_prep_dma_memset;
2352 atxdmac->dma.device_prep_dma_memset_sg = at_xdmac_prep_dma_memset_sg;
2353 atxdmac->dma.device_prep_slave_sg = at_xdmac_prep_slave_sg;
2354 atxdmac->dma.device_config = at_xdmac_device_config;
2355 atxdmac->dma.device_pause = at_xdmac_device_pause;
2356 atxdmac->dma.device_resume = at_xdmac_device_resume;
2357 atxdmac->dma.device_terminate_all = at_xdmac_device_terminate_all;
2358 atxdmac->dma.src_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
2359 atxdmac->dma.dst_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
2360 atxdmac->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
2361 atxdmac->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
2362
2363 platform_set_drvdata(pdev, data: atxdmac);
2364
2365 pm_runtime_set_autosuspend_delay(dev: &pdev->dev, delay: 500);
2366 pm_runtime_use_autosuspend(dev: &pdev->dev);
2367 pm_runtime_set_active(dev: &pdev->dev);
2368 pm_runtime_enable(dev: &pdev->dev);
2369 pm_runtime_get_noresume(dev: &pdev->dev);
2370
2371 /* Init channels. */
2372 INIT_LIST_HEAD(list: &atxdmac->dma.channels);
2373
2374 /* Disable all chans and interrupts. */
2375 at_xdmac_off(atxdmac, suspend_descriptors: true);
2376
2377 for (i = 0; i < nr_channels; i++) {
2378 struct at_xdmac_chan *atchan = &atxdmac->chan[i];
2379
2380 atchan->chan.device = &atxdmac->dma;
2381 list_add_tail(new: &atchan->chan.device_node,
2382 head: &atxdmac->dma.channels);
2383
2384 atchan->ch_regs = at_xdmac_chan_reg_base(atxdmac, chan_nb: i);
2385 atchan->mask = 1 << i;
2386
2387 spin_lock_init(&atchan->lock);
2388 INIT_LIST_HEAD(list: &atchan->xfers_list);
2389 INIT_LIST_HEAD(list: &atchan->free_descs_list);
2390 tasklet_setup(t: &atchan->tasklet, callback: at_xdmac_tasklet);
2391
2392 /* Clear pending interrupts. */
2393 while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
2394 cpu_relax();
2395 }
2396
2397 ret = dma_async_device_register(device: &atxdmac->dma);
2398 if (ret) {
2399 dev_err(&pdev->dev, "fail to register DMA engine device\n");
2400 goto err_pm_disable;
2401 }
2402
2403 ret = of_dma_controller_register(np: pdev->dev.of_node,
2404 of_dma_xlate: at_xdmac_xlate, data: atxdmac);
2405 if (ret) {
2406 dev_err(&pdev->dev, "could not register of dma controller\n");
2407 goto err_dma_unregister;
2408 }
2409
2410 dev_info(&pdev->dev, "%d channels, mapped at 0x%p\n",
2411 nr_channels, atxdmac->regs);
2412
2413 at_xdmac_axi_config(pdev);
2414
2415 pm_runtime_mark_last_busy(dev: &pdev->dev);
2416 pm_runtime_put_autosuspend(dev: &pdev->dev);
2417
2418 return 0;
2419
2420err_dma_unregister:
2421 dma_async_device_unregister(device: &atxdmac->dma);
2422err_pm_disable:
2423 pm_runtime_put_noidle(dev: &pdev->dev);
2424 pm_runtime_disable(dev: &pdev->dev);
2425 pm_runtime_set_suspended(dev: &pdev->dev);
2426 pm_runtime_dont_use_autosuspend(dev: &pdev->dev);
2427err_clk_disable:
2428 clk_disable_unprepare(clk: atxdmac->clk);
2429err_free_irq:
2430 free_irq(atxdmac->irq, atxdmac);
2431 return ret;
2432}
2433
2434static void at_xdmac_remove(struct platform_device *pdev)
2435{
2436 struct at_xdmac *atxdmac = (struct at_xdmac *)platform_get_drvdata(pdev);
2437 int i;
2438
2439 at_xdmac_off(atxdmac, suspend_descriptors: true);
2440 of_dma_controller_free(np: pdev->dev.of_node);
2441 dma_async_device_unregister(device: &atxdmac->dma);
2442 pm_runtime_disable(dev: atxdmac->dev);
2443 pm_runtime_set_suspended(dev: &pdev->dev);
2444 pm_runtime_dont_use_autosuspend(dev: &pdev->dev);
2445 clk_disable_unprepare(clk: atxdmac->clk);
2446
2447 free_irq(atxdmac->irq, atxdmac);
2448
2449 for (i = 0; i < atxdmac->dma.chancnt; i++) {
2450 struct at_xdmac_chan *atchan = &atxdmac->chan[i];
2451
2452 tasklet_kill(t: &atchan->tasklet);
2453 at_xdmac_free_chan_resources(chan: &atchan->chan);
2454 }
2455}
2456
2457static const struct dev_pm_ops __maybe_unused atmel_xdmac_dev_pm_ops = {
2458 .prepare = atmel_xdmac_prepare,
2459 SET_LATE_SYSTEM_SLEEP_PM_OPS(atmel_xdmac_suspend, atmel_xdmac_resume)
2460 SET_RUNTIME_PM_OPS(atmel_xdmac_runtime_suspend,
2461 atmel_xdmac_runtime_resume, NULL)
2462};
2463
2464static const struct of_device_id atmel_xdmac_dt_ids[] = {
2465 {
2466 .compatible = "atmel,sama5d4-dma",
2467 .data = &at_xdmac_sama5d4_layout,
2468 }, {
2469 .compatible = "microchip,sama7g5-dma",
2470 .data = &at_xdmac_sama7g5_layout,
2471 }, {
2472 /* sentinel */
2473 }
2474};
2475MODULE_DEVICE_TABLE(of, atmel_xdmac_dt_ids);
2476
2477static struct platform_driver at_xdmac_driver = {
2478 .probe = at_xdmac_probe,
2479 .remove_new = at_xdmac_remove,
2480 .driver = {
2481 .name = "at_xdmac",
2482 .of_match_table = of_match_ptr(atmel_xdmac_dt_ids),
2483 .pm = pm_ptr(&atmel_xdmac_dev_pm_ops),
2484 }
2485};
2486
2487static int __init at_xdmac_init(void)
2488{
2489 return platform_driver_register(&at_xdmac_driver);
2490}
2491subsys_initcall(at_xdmac_init);
2492
2493static void __exit at_xdmac_exit(void)
2494{
2495 platform_driver_unregister(&at_xdmac_driver);
2496}
2497module_exit(at_xdmac_exit);
2498
2499MODULE_DESCRIPTION("Atmel Extended DMA Controller driver");
2500MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>");
2501MODULE_LICENSE("GPL");
2502

source code of linux/drivers/dma/at_xdmac.c