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[mirror_ubuntu-bionic-kernel.git] / drivers / dma / stm32-dma.c
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d8b46839
CM		 1/*
2 * Driver for STM32 DMA controller
3 *
4 * Inspired by dma-jz4740.c and tegra20-apb-dma.c
5 *
6 * Copyright (C) M'boumba Cedric Madianga 2015
7 * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com>
8 *
9 * License terms: GNU General Public License (GPL), version 2
10 */
11
12#include <linux/clk.h>
13#include <linux/delay.h>
14#include <linux/dmaengine.h>
15#include <linux/dma-mapping.h>
16#include <linux/err.h>
17#include <linux/init.h>
18#include <linux/jiffies.h>
19#include <linux/list.h>
20#include <linux/module.h>
21#include <linux/of.h>
22#include <linux/of_device.h>
23#include <linux/of_dma.h>
24#include <linux/platform_device.h>
25#include <linux/reset.h>
26#include <linux/sched.h>
27#include <linux/slab.h>
28
29#include "virt-dma.h"
30
31#define STM32_DMA_LISR 0x0000 /* DMA Low Int Status Reg */
32#define STM32_DMA_HISR 0x0004 /* DMA High Int Status Reg */
33#define STM32_DMA_LIFCR 0x0008 /* DMA Low Int Flag Clear Reg */
34#define STM32_DMA_HIFCR 0x000c /* DMA High Int Flag Clear Reg */
35#define STM32_DMA_TCI BIT(5) /* Transfer Complete Interrupt */
36#define STM32_DMA_TEI BIT(3) /* Transfer Error Interrupt */
37#define STM32_DMA_DMEI BIT(2) /* Direct Mode Error Interrupt */
38#define STM32_DMA_FEI BIT(0) /* FIFO Error Interrupt */
39
40/* DMA Stream x Configuration Register */
41#define STM32_DMA_SCR(x) (0x0010 + 0x18 * (x)) /* x = 0..7 */
42#define STM32_DMA_SCR_REQ(n) ((n & 0x7) << 25)
43#define STM32_DMA_SCR_MBURST_MASK GENMASK(24, 23)
44#define STM32_DMA_SCR_MBURST(n) ((n & 0x3) << 23)
45#define STM32_DMA_SCR_PBURST_MASK GENMASK(22, 21)
46#define STM32_DMA_SCR_PBURST(n) ((n & 0x3) << 21)
47#define STM32_DMA_SCR_PL_MASK GENMASK(17, 16)
48#define STM32_DMA_SCR_PL(n) ((n & 0x3) << 16)
49#define STM32_DMA_SCR_MSIZE_MASK GENMASK(14, 13)
50#define STM32_DMA_SCR_MSIZE(n) ((n & 0x3) << 13)
51#define STM32_DMA_SCR_PSIZE_MASK GENMASK(12, 11)
52#define STM32_DMA_SCR_PSIZE(n) ((n & 0x3) << 11)
53#define STM32_DMA_SCR_PSIZE_GET(n) ((n & STM32_DMA_SCR_PSIZE_MASK) >> 11)
54#define STM32_DMA_SCR_DIR_MASK GENMASK(7, 6)
55#define STM32_DMA_SCR_DIR(n) ((n & 0x3) << 6)
56#define STM32_DMA_SCR_CT BIT(19) /* Target in double buffer */
57#define STM32_DMA_SCR_DBM BIT(18) /* Double Buffer Mode */
58#define STM32_DMA_SCR_PINCOS BIT(15) /* Peripheral inc offset size */
59#define STM32_DMA_SCR_MINC BIT(10) /* Memory increment mode */
60#define STM32_DMA_SCR_PINC BIT(9) /* Peripheral increment mode */
61#define STM32_DMA_SCR_CIRC BIT(8) /* Circular mode */
62#define STM32_DMA_SCR_PFCTRL BIT(5) /* Peripheral Flow Controller */
63#define STM32_DMA_SCR_TCIE BIT(4) /* Transfer Cplete Int Enable*/
64#define STM32_DMA_SCR_TEIE BIT(2) /* Transfer Error Int Enable */
65#define STM32_DMA_SCR_DMEIE BIT(1) /* Direct Mode Err Int Enable */
66#define STM32_DMA_SCR_EN BIT(0) /* Stream Enable */
67#define STM32_DMA_SCR_CFG_MASK (STM32_DMA_SCR_PINC \
68 | STM32_DMA_SCR_MINC \
69 | STM32_DMA_SCR_PINCOS \
70 | STM32_DMA_SCR_PL_MASK)
71#define STM32_DMA_SCR_IRQ_MASK (STM32_DMA_SCR_TCIE \
72 | STM32_DMA_SCR_TEIE \
73 | STM32_DMA_SCR_DMEIE)
74
75/* DMA Stream x number of data register */
76#define STM32_DMA_SNDTR(x) (0x0014 + 0x18 * (x))
77
78/* DMA stream peripheral address register */
79#define STM32_DMA_SPAR(x) (0x0018 + 0x18 * (x))
80
81/* DMA stream x memory 0 address register */
82#define STM32_DMA_SM0AR(x) (0x001c + 0x18 * (x))
83
84/* DMA stream x memory 1 address register */
85#define STM32_DMA_SM1AR(x) (0x0020 + 0x18 * (x))
86
87/* DMA stream x FIFO control register */
88#define STM32_DMA_SFCR(x) (0x0024 + 0x18 * (x))
89#define STM32_DMA_SFCR_FTH_MASK GENMASK(1, 0)
90#define STM32_DMA_SFCR_FTH(n) (n & STM32_DMA_SFCR_FTH_MASK)
91#define STM32_DMA_SFCR_FEIE BIT(7) /* FIFO error interrupt enable */
92#define STM32_DMA_SFCR_DMDIS BIT(2) /* Direct mode disable */
93#define STM32_DMA_SFCR_MASK (STM32_DMA_SFCR_FEIE \
94 | STM32_DMA_SFCR_DMDIS)
95
96/* DMA direction */
97#define STM32_DMA_DEV_TO_MEM 0x00
98#define STM32_DMA_MEM_TO_DEV 0x01
99#define STM32_DMA_MEM_TO_MEM 0x02
100
101/* DMA priority level */
102#define STM32_DMA_PRIORITY_LOW 0x00
103#define STM32_DMA_PRIORITY_MEDIUM 0x01
104#define STM32_DMA_PRIORITY_HIGH 0x02
105#define STM32_DMA_PRIORITY_VERY_HIGH 0x03
106
107/* DMA FIFO threshold selection */
108#define STM32_DMA_FIFO_THRESHOLD_1QUARTERFULL 0x00
109#define STM32_DMA_FIFO_THRESHOLD_HALFFULL 0x01
110#define STM32_DMA_FIFO_THRESHOLD_3QUARTERSFULL 0x02
111#define STM32_DMA_FIFO_THRESHOLD_FULL 0x03
112
113#define STM32_DMA_MAX_DATA_ITEMS 0xffff
114#define STM32_DMA_MAX_CHANNELS 0x08
115#define STM32_DMA_MAX_REQUEST_ID 0x08
116#define STM32_DMA_MAX_DATA_PARAM 0x03
117
118enum stm32_dma_width {
119 STM32_DMA_BYTE,
120 STM32_DMA_HALF_WORD,
121 STM32_DMA_WORD,
122};
123
124enum stm32_dma_burst_size {
125 STM32_DMA_BURST_SINGLE,
126 STM32_DMA_BURST_INCR4,
127 STM32_DMA_BURST_INCR8,
128 STM32_DMA_BURST_INCR16,
129};
130
131struct stm32_dma_cfg {
132 u32 channel_id;
133 u32 request_line;
134 u32 stream_config;
135 u32 threshold;
136};
137
138struct stm32_dma_chan_reg {
139 u32 dma_lisr;
140 u32 dma_hisr;
141 u32 dma_lifcr;
142 u32 dma_hifcr;
143 u32 dma_scr;
144 u32 dma_sndtr;
145 u32 dma_spar;
146 u32 dma_sm0ar;
147 u32 dma_sm1ar;
148 u32 dma_sfcr;
149};
150
151struct stm32_dma_sg_req {
152 u32 len;
153 struct stm32_dma_chan_reg chan_reg;
154};
155
156struct stm32_dma_desc {
157 struct virt_dma_desc vdesc;
158 bool cyclic;
159 u32 num_sgs;
160 struct stm32_dma_sg_req sg_req[];
161};
162
163struct stm32_dma_chan {
164 struct virt_dma_chan vchan;
165 bool config_init;
166 bool busy;
167 u32 id;
168 u32 irq;
169 struct stm32_dma_desc *desc;
170 u32 next_sg;
171 struct dma_slave_config dma_sconfig;
172 struct stm32_dma_chan_reg chan_reg;
173};
174
175struct stm32_dma_device {
176 struct dma_device ddev;
177 void __iomem *base;
178 struct clk *clk;
179 struct reset_control *rst;
180 bool mem2mem;
181 struct stm32_dma_chan chan[STM32_DMA_MAX_CHANNELS];
182};
183
184static struct stm32_dma_device *stm32_dma_get_dev(struct stm32_dma_chan *chan)
185{
186 return container_of(chan->vchan.chan.device, struct stm32_dma_device,
187 ddev);
188}
189
190static struct stm32_dma_chan *to_stm32_dma_chan(struct dma_chan *c)
191{
192 return container_of(c, struct stm32_dma_chan, vchan.chan);
193}
194
195static struct stm32_dma_desc *to_stm32_dma_desc(struct virt_dma_desc *vdesc)
196{
197 return container_of(vdesc, struct stm32_dma_desc, vdesc);
198}
199
200static struct device *chan2dev(struct stm32_dma_chan *chan)
201{
202 return &chan->vchan.chan.dev->device;
203}
204
205static u32 stm32_dma_read(struct stm32_dma_device *dmadev, u32 reg)
206{
207 return readl_relaxed(dmadev->base + reg);
208}
209
210static void stm32_dma_write(struct stm32_dma_device *dmadev, u32 reg, u32 val)
211{
212 writel_relaxed(val, dmadev->base + reg);
213}
214
215static struct stm32_dma_desc *stm32_dma_alloc_desc(u32 num_sgs)
216{
217 return kzalloc(sizeof(struct stm32_dma_desc) +
218 sizeof(struct stm32_dma_sg_req) * num_sgs, GFP_NOWAIT);
219}
220
221static int stm32_dma_get_width(struct stm32_dma_chan *chan,
222 enum dma_slave_buswidth width)
223{
224 switch (width) {
225 case DMA_SLAVE_BUSWIDTH_1_BYTE:
226 return STM32_DMA_BYTE;
227 case DMA_SLAVE_BUSWIDTH_2_BYTES:
228 return STM32_DMA_HALF_WORD;
229 case DMA_SLAVE_BUSWIDTH_4_BYTES:
230 return STM32_DMA_WORD;
231 default:
232 dev_err(chan2dev(chan), "Dma bus width not supported\n");
233 return -EINVAL;
234 }
235}
236
237static int stm32_dma_get_burst(struct stm32_dma_chan *chan, u32 maxburst)
238{
239 switch (maxburst) {
240 case 0:
241 case 1:
242 return STM32_DMA_BURST_SINGLE;
243 case 4:
244 return STM32_DMA_BURST_INCR4;
245 case 8:
246 return STM32_DMA_BURST_INCR8;
247 case 16:
248 return STM32_DMA_BURST_INCR16;
249 default:
250 dev_err(chan2dev(chan), "Dma burst size not supported\n");
251 return -EINVAL;
252 }
253}
254
255static void stm32_dma_set_fifo_config(struct stm32_dma_chan *chan,
256 u32 src_maxburst, u32 dst_maxburst)
257{
258 chan->chan_reg.dma_sfcr &= ~STM32_DMA_SFCR_MASK;
259 chan->chan_reg.dma_scr &= ~STM32_DMA_SCR_DMEIE;
260
261 if ((!src_maxburst) && (!dst_maxburst)) {
262 /* Using direct mode */
263 chan->chan_reg.dma_scr |= STM32_DMA_SCR_DMEIE;
264 } else {
265 /* Using FIFO mode */
266 chan->chan_reg.dma_sfcr |= STM32_DMA_SFCR_MASK;
267 }
268}
269
270static int stm32_dma_slave_config(struct dma_chan *c,
271 struct dma_slave_config *config)
272{
273 struct stm32_dma_chan *chan = to_stm32_dma_chan(c);
274
275 memcpy(&chan->dma_sconfig, config, sizeof(*config));
276
277 chan->config_init = true;
278
279 return 0;
280}
281
282static u32 stm32_dma_irq_status(struct stm32_dma_chan *chan)
283{
284 struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan);
285 u32 flags, dma_isr;
286
287 /*
288 * Read "flags" from DMA_xISR register corresponding to the selected
289 * DMA channel at the correct bit offset inside that register.
290 *
291 * If (ch % 4) is 2 or 3, left shift the mask by 16 bits.
292 * If (ch % 4) is 1 or 3, additionally left shift the mask by 6 bits.
293 */
294
295 if (chan->id & 4)
296 dma_isr = stm32_dma_read(dmadev, STM32_DMA_HISR);
297 else
298 dma_isr = stm32_dma_read(dmadev, STM32_DMA_LISR);
299
300 flags = dma_isr >> (((chan->id & 2) << 3) | ((chan->id & 1) * 6));
301
302 return flags;
303}
304
305static void stm32_dma_irq_clear(struct stm32_dma_chan *chan, u32 flags)
306{
307 struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan);
308 u32 dma_ifcr;
309
310 /*
311 * Write "flags" to the DMA_xIFCR register corresponding to the selected
312 * DMA channel at the correct bit offset inside that register.
313 *
314 * If (ch % 4) is 2 or 3, left shift the mask by 16 bits.
315 * If (ch % 4) is 1 or 3, additionally left shift the mask by 6 bits.
316 */
317 dma_ifcr = flags << (((chan->id & 2) << 3) | ((chan->id & 1) * 6));
318
319 if (chan->id & 4)
320 stm32_dma_write(dmadev, STM32_DMA_HIFCR, dma_ifcr);
321 else
322 stm32_dma_write(dmadev, STM32_DMA_LIFCR, dma_ifcr);
323}
324
325static int stm32_dma_disable_chan(struct stm32_dma_chan *chan)
326{
327 struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan);
328 unsigned long timeout = jiffies + msecs_to_jiffies(5000);
329 u32 dma_scr, id;
330
331 id = chan->id;
332 dma_scr = stm32_dma_read(dmadev, STM32_DMA_SCR(id));
333
334 if (dma_scr & STM32_DMA_SCR_EN) {
335 dma_scr &= ~STM32_DMA_SCR_EN;
336 stm32_dma_write(dmadev, STM32_DMA_SCR(id), dma_scr);
337
338 do {
339 dma_scr = stm32_dma_read(dmadev, STM32_DMA_SCR(id));
340 dma_scr &= STM32_DMA_SCR_EN;
341 if (!dma_scr)
342 break;
343
344 if (time_after_eq(jiffies, timeout)) {
345 dev_err(chan2dev(chan), "%s: timeout!\n",
346 __func__);
347 return -EBUSY;
348 }
349 cond_resched();
350 } while (1);
351 }
352
353 return 0;
354}
355
356static void stm32_dma_stop(struct stm32_dma_chan *chan)
357{
358 struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan);
359 u32 dma_scr, dma_sfcr, status;
360 int ret;
361
362 /* Disable interrupts */
363 dma_scr = stm32_dma_read(dmadev, STM32_DMA_SCR(chan->id));
364 dma_scr &= ~STM32_DMA_SCR_IRQ_MASK;
365 stm32_dma_write(dmadev, STM32_DMA_SCR(chan->id), dma_scr);
366 dma_sfcr = stm32_dma_read(dmadev, STM32_DMA_SFCR(chan->id));
367 dma_sfcr &= ~STM32_DMA_SFCR_FEIE;
368 stm32_dma_write(dmadev, STM32_DMA_SFCR(chan->id), dma_sfcr);
369
370 /* Disable DMA */
371 ret = stm32_dma_disable_chan(chan);
372 if (ret < 0)
373 return;
374
375 /* Clear interrupt status if it is there */
376 status = stm32_dma_irq_status(chan);
377 if (status) {
378 dev_dbg(chan2dev(chan), "%s(): clearing interrupt: 0x%08x\n",
379 __func__, status);
380 stm32_dma_irq_clear(chan, status);
381 }
382
383 chan->busy = false;
384}
385
386static int stm32_dma_terminate_all(struct dma_chan *c)
387{
388 struct stm32_dma_chan *chan = to_stm32_dma_chan(c);
389 unsigned long flags;
390 LIST_HEAD(head);
391
392 spin_lock_irqsave(&chan->vchan.lock, flags);
393
394 if (chan->busy) {
395 stm32_dma_stop(chan);
396 chan->desc = NULL;
397 }
398
399 vchan_get_all_descriptors(&chan->vchan, &head);
400 spin_unlock_irqrestore(&chan->vchan.lock, flags);
401 vchan_dma_desc_free_list(&chan->vchan, &head);
402
403 return 0;
404}
405
406static void stm32_dma_dump_reg(struct stm32_dma_chan *chan)
407{
408 struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan);
409 u32 scr = stm32_dma_read(dmadev, STM32_DMA_SCR(chan->id));
410 u32 ndtr = stm32_dma_read(dmadev, STM32_DMA_SNDTR(chan->id));
411 u32 spar = stm32_dma_read(dmadev, STM32_DMA_SPAR(chan->id));
412 u32 sm0ar = stm32_dma_read(dmadev, STM32_DMA_SM0AR(chan->id));
413 u32 sm1ar = stm32_dma_read(dmadev, STM32_DMA_SM1AR(chan->id));
414 u32 sfcr = stm32_dma_read(dmadev, STM32_DMA_SFCR(chan->id));
415
416 dev_dbg(chan2dev(chan), "SCR: 0x%08x\n", scr);
417 dev_dbg(chan2dev(chan), "NDTR: 0x%08x\n", ndtr);
418 dev_dbg(chan2dev(chan), "SPAR: 0x%08x\n", spar);
419 dev_dbg(chan2dev(chan), "SM0AR: 0x%08x\n", sm0ar);
420 dev_dbg(chan2dev(chan), "SM1AR: 0x%08x\n", sm1ar);
421 dev_dbg(chan2dev(chan), "SFCR: 0x%08x\n", sfcr);
422}
423
424static int stm32_dma_start_transfer(struct stm32_dma_chan *chan)
425{
426 struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan);
427 struct virt_dma_desc *vdesc;
428 struct stm32_dma_sg_req *sg_req;
429 struct stm32_dma_chan_reg *reg;
430 u32 status;
431 int ret;
432
433 ret = stm32_dma_disable_chan(chan);
434 if (ret < 0)
435 return ret;
436
437 if (!chan->desc) {
438 vdesc = vchan_next_desc(&chan->vchan);
439 if (!vdesc)
aea08a5d 440 return -EPERM;
d8b46839
CM		 441
442 chan->desc = to_stm32_dma_desc(vdesc);
443 chan->next_sg = 0;
444 }
445
446 if (chan->next_sg == chan->desc->num_sgs)
447 chan->next_sg = 0;
448
449 sg_req = &chan->desc->sg_req[chan->next_sg];
450 reg = &sg_req->chan_reg;
451
452 stm32_dma_write(dmadev, STM32_DMA_SCR(chan->id), reg->dma_scr);
453 stm32_dma_write(dmadev, STM32_DMA_SPAR(chan->id), reg->dma_spar);
454 stm32_dma_write(dmadev, STM32_DMA_SM0AR(chan->id), reg->dma_sm0ar);
455 stm32_dma_write(dmadev, STM32_DMA_SFCR(chan->id), reg->dma_sfcr);
456 stm32_dma_write(dmadev, STM32_DMA_SM1AR(chan->id), reg->dma_sm1ar);
457 stm32_dma_write(dmadev, STM32_DMA_SNDTR(chan->id), reg->dma_sndtr);
458
459 chan->next_sg++;
460
461 /* Clear interrupt status if it is there */
462 status = stm32_dma_irq_status(chan);
463 if (status)
464 stm32_dma_irq_clear(chan, status);
465
466 stm32_dma_dump_reg(chan);
467
468 /* Start DMA */
469 reg->dma_scr |= STM32_DMA_SCR_EN;
470 stm32_dma_write(dmadev, STM32_DMA_SCR(chan->id), reg->dma_scr);
471
472 chan->busy = true;
473
474 return 0;
475}
476
477static void stm32_dma_configure_next_sg(struct stm32_dma_chan *chan)
478{
479 struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan);
480 struct stm32_dma_sg_req *sg_req;
481 u32 dma_scr, dma_sm0ar, dma_sm1ar, id;
482
483 id = chan->id;
484 dma_scr = stm32_dma_read(dmadev, STM32_DMA_SCR(id));
485
486 if (dma_scr & STM32_DMA_SCR_DBM) {
487 if (chan->next_sg == chan->desc->num_sgs)
488 chan->next_sg = 0;
489
490 sg_req = &chan->desc->sg_req[chan->next_sg];
491
492 if (dma_scr & STM32_DMA_SCR_CT) {
493 dma_sm0ar = sg_req->chan_reg.dma_sm0ar;
494 stm32_dma_write(dmadev, STM32_DMA_SM0AR(id), dma_sm0ar);
495 dev_dbg(chan2dev(chan), "CT=1 <=> SM0AR: 0x%08x\n",
496 stm32_dma_read(dmadev, STM32_DMA_SM0AR(id)));
497 } else {
498 dma_sm1ar = sg_req->chan_reg.dma_sm1ar;
499 stm32_dma_write(dmadev, STM32_DMA_SM1AR(id), dma_sm1ar);
500 dev_dbg(chan2dev(chan), "CT=0 <=> SM1AR: 0x%08x\n",
501 stm32_dma_read(dmadev, STM32_DMA_SM1AR(id)));
502 }
503
504 chan->next_sg++;
505 }
506}
507
508static void stm32_dma_handle_chan_done(struct stm32_dma_chan *chan)
509{
510 if (chan->desc) {
511 if (chan->desc->cyclic) {
512 vchan_cyclic_callback(&chan->desc->vdesc);
513 stm32_dma_configure_next_sg(chan);
514 } else {
515 chan->busy = false;
516 if (chan->next_sg == chan->desc->num_sgs) {
517 list_del(&chan->desc->vdesc.node);
518 vchan_cookie_complete(&chan->desc->vdesc);
519 chan->desc = NULL;
520 }
521 stm32_dma_start_transfer(chan);
522 }
523 }
524}
525
526static irqreturn_t stm32_dma_chan_irq(int irq, void *devid)
527{
528 struct stm32_dma_chan *chan = devid;
529 struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan);
1bc4f06c 530 u32 status, scr;
d8b46839
CM		 531
532 spin_lock(&chan->vchan.lock);
533
534 status = stm32_dma_irq_status(chan);
535 scr = stm32_dma_read(dmadev, STM32_DMA_SCR(chan->id));
d8b46839
CM		 536
537 if ((status & STM32_DMA_TCI) && (scr & STM32_DMA_SCR_TCIE)) {
538 stm32_dma_irq_clear(chan, STM32_DMA_TCI);
539 stm32_dma_handle_chan_done(chan);
540
541 } else {
542 stm32_dma_irq_clear(chan, status);
543 dev_err(chan2dev(chan), "DMA error: status=0x%08x\n", status);
544 }
545
546 spin_unlock(&chan->vchan.lock);
547
548 return IRQ_HANDLED;
549}
550
551static void stm32_dma_issue_pending(struct dma_chan *c)
552{
553 struct stm32_dma_chan *chan = to_stm32_dma_chan(c);
554 unsigned long flags;
555 int ret;
556
557 spin_lock_irqsave(&chan->vchan.lock, flags);
558 if (!chan->busy) {
559 if (vchan_issue_pending(&chan->vchan) && !chan->desc) {
560 ret = stm32_dma_start_transfer(chan);
aea08a5d 561 if ((!ret) && (chan->desc->cyclic))
d8b46839
CM		 562 stm32_dma_configure_next_sg(chan);
563 }
564 }
565 spin_unlock_irqrestore(&chan->vchan.lock, flags);
566}
567
568static int stm32_dma_set_xfer_param(struct stm32_dma_chan *chan,
569 enum dma_transfer_direction direction,
570 enum dma_slave_buswidth *buswidth)
571{
572 enum dma_slave_buswidth src_addr_width, dst_addr_width;
573 int src_bus_width, dst_bus_width;
574 int src_burst_size, dst_burst_size;
575 u32 src_maxburst, dst_maxburst;
d8b46839
CM		 576 u32 dma_scr = 0;
577
578 src_addr_width = chan->dma_sconfig.src_addr_width;
579 dst_addr_width = chan->dma_sconfig.dst_addr_width;
580 src_maxburst = chan->dma_sconfig.src_maxburst;
581 dst_maxburst = chan->dma_sconfig.dst_maxburst;
d8b46839
CM		 582
583 switch (direction) {
584 case DMA_MEM_TO_DEV:
585 dst_bus_width = stm32_dma_get_width(chan, dst_addr_width);
586 if (dst_bus_width < 0)
587 return dst_bus_width;
588
589 dst_burst_size = stm32_dma_get_burst(chan, dst_maxburst);
590 if (dst_burst_size < 0)
591 return dst_burst_size;
592
593 if (!src_addr_width)
594 src_addr_width = dst_addr_width;
595
596 src_bus_width = stm32_dma_get_width(chan, src_addr_width);
597 if (src_bus_width < 0)
598 return src_bus_width;
599
600 src_burst_size = stm32_dma_get_burst(chan, src_maxburst);
601 if (src_burst_size < 0)
602 return src_burst_size;
603
604 dma_scr = STM32_DMA_SCR_DIR(STM32_DMA_MEM_TO_DEV) |
605 STM32_DMA_SCR_PSIZE(dst_bus_width) |
606 STM32_DMA_SCR_MSIZE(src_bus_width) |
607 STM32_DMA_SCR_PBURST(dst_burst_size) |
608 STM32_DMA_SCR_MBURST(src_burst_size);
609
610 chan->chan_reg.dma_spar = chan->dma_sconfig.dst_addr;
611 *buswidth = dst_addr_width;
612 break;
613
614 case DMA_DEV_TO_MEM:
615 src_bus_width = stm32_dma_get_width(chan, src_addr_width);
616 if (src_bus_width < 0)
617 return src_bus_width;
618
619 src_burst_size = stm32_dma_get_burst(chan, src_maxburst);
620 if (src_burst_size < 0)
621 return src_burst_size;
622
623 if (!dst_addr_width)
624 dst_addr_width = src_addr_width;
625
626 dst_bus_width = stm32_dma_get_width(chan, dst_addr_width);
627 if (dst_bus_width < 0)
628 return dst_bus_width;
629
630 dst_burst_size = stm32_dma_get_burst(chan, dst_maxburst);
631 if (dst_burst_size < 0)
632 return dst_burst_size;
633
634 dma_scr = STM32_DMA_SCR_DIR(STM32_DMA_DEV_TO_MEM) |
635 STM32_DMA_SCR_PSIZE(src_bus_width) |
636 STM32_DMA_SCR_MSIZE(dst_bus_width) |
637 STM32_DMA_SCR_PBURST(src_burst_size) |
638 STM32_DMA_SCR_MBURST(dst_burst_size);
639
640 chan->chan_reg.dma_spar = chan->dma_sconfig.src_addr;
641 *buswidth = chan->dma_sconfig.src_addr_width;
642 break;
643
644 default:
645 dev_err(chan2dev(chan), "Dma direction is not supported\n");
646 return -EINVAL;
647 }
648
649 stm32_dma_set_fifo_config(chan, src_maxburst, dst_maxburst);
650
651 chan->chan_reg.dma_scr &= ~(STM32_DMA_SCR_DIR_MASK |
652 STM32_DMA_SCR_PSIZE_MASK | STM32_DMA_SCR_MSIZE_MASK |
653 STM32_DMA_SCR_PBURST_MASK | STM32_DMA_SCR_MBURST_MASK);
654 chan->chan_reg.dma_scr |= dma_scr;
655
656 return 0;
657}
658
659static void stm32_dma_clear_reg(struct stm32_dma_chan_reg *regs)
660{
661 memset(regs, 0, sizeof(struct stm32_dma_chan_reg));
662}
663
664static struct dma_async_tx_descriptor *stm32_dma_prep_slave_sg(
665 struct dma_chan *c, struct scatterlist *sgl,
666 u32 sg_len, enum dma_transfer_direction direction,
667 unsigned long flags, void *context)
668{
669 struct stm32_dma_chan *chan = to_stm32_dma_chan(c);
670 struct stm32_dma_desc *desc;
671 struct scatterlist *sg;
672 enum dma_slave_buswidth buswidth;
673 u32 nb_data_items;
674 int i, ret;
675
676 if (!chan->config_init) {
677 dev_err(chan2dev(chan), "dma channel is not configured\n");
678 return NULL;
679 }
680
681 if (sg_len < 1) {
682 dev_err(chan2dev(chan), "Invalid segment length %d\n", sg_len);
683 return NULL;
684 }
685
686 desc = stm32_dma_alloc_desc(sg_len);
687 if (!desc)
688 return NULL;
689
690 ret = stm32_dma_set_xfer_param(chan, direction, &buswidth);
691 if (ret < 0)
692 goto err;
693
694 /* Set peripheral flow controller */
695 if (chan->dma_sconfig.device_fc)
696 chan->chan_reg.dma_scr |= STM32_DMA_SCR_PFCTRL;
697 else
698 chan->chan_reg.dma_scr &= ~STM32_DMA_SCR_PFCTRL;
699
700 for_each_sg(sgl, sg, sg_len, i) {
701 desc->sg_req[i].len = sg_dma_len(sg);
702
703 nb_data_items = desc->sg_req[i].len / buswidth;
704 if (nb_data_items > STM32_DMA_MAX_DATA_ITEMS) {
705 dev_err(chan2dev(chan), "nb items not supported\n");
706 goto err;
707 }
708
709 stm32_dma_clear_reg(&desc->sg_req[i].chan_reg);
710 desc->sg_req[i].chan_reg.dma_scr = chan->chan_reg.dma_scr;
711 desc->sg_req[i].chan_reg.dma_sfcr = chan->chan_reg.dma_sfcr;
712 desc->sg_req[i].chan_reg.dma_spar = chan->chan_reg.dma_spar;
713 desc->sg_req[i].chan_reg.dma_sm0ar = sg_dma_address(sg);
714 desc->sg_req[i].chan_reg.dma_sm1ar = sg_dma_address(sg);
715 desc->sg_req[i].chan_reg.dma_sndtr = nb_data_items;
716 }
717
718 desc->num_sgs = sg_len;
719 desc->cyclic = false;
720
721 return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
722
723err:
724 kfree(desc);
725 return NULL;
726}
727
728static struct dma_async_tx_descriptor *stm32_dma_prep_dma_cyclic(
729 struct dma_chan *c, dma_addr_t buf_addr, size_t buf_len,
730 size_t period_len, enum dma_transfer_direction direction,
731 unsigned long flags)
732{
733 struct stm32_dma_chan *chan = to_stm32_dma_chan(c);
734 struct stm32_dma_desc *desc;
735 enum dma_slave_buswidth buswidth;
736 u32 num_periods, nb_data_items;
737 int i, ret;
738
739 if (!buf_len || !period_len) {
740 dev_err(chan2dev(chan), "Invalid buffer/period len\n");
741 return NULL;
742 }
743
744 if (!chan->config_init) {
745 dev_err(chan2dev(chan), "dma channel is not configured\n");
746 return NULL;
747 }
748
749 if (buf_len % period_len) {
750 dev_err(chan2dev(chan), "buf_len not multiple of period_len\n");
751 return NULL;
752 }
753
754 /*
755 * We allow to take more number of requests till DMA is
756 * not started. The driver will loop over all requests.
757 * Once DMA is started then new requests can be queued only after
758 * terminating the DMA.
759 */
760 if (chan->busy) {
761 dev_err(chan2dev(chan), "Request not allowed when dma busy\n");
762 return NULL;
763 }
764
765 ret = stm32_dma_set_xfer_param(chan, direction, &buswidth);
766 if (ret < 0)
767 return NULL;
768
769 nb_data_items = period_len / buswidth;
770 if (nb_data_items > STM32_DMA_MAX_DATA_ITEMS) {
771 dev_err(chan2dev(chan), "number of items not supported\n");
772 return NULL;
773 }
774
775 /* Enable Circular mode or double buffer mode */
776 if (buf_len == period_len)
777 chan->chan_reg.dma_scr |= STM32_DMA_SCR_CIRC;
778 else
779 chan->chan_reg.dma_scr |= STM32_DMA_SCR_DBM;
780
781 /* Clear periph ctrl if client set it */
782 chan->chan_reg.dma_scr &= ~STM32_DMA_SCR_PFCTRL;
783
784 num_periods = buf_len / period_len;
785
786 desc = stm32_dma_alloc_desc(num_periods);
787 if (!desc)
788 return NULL;
789
790 for (i = 0; i < num_periods; i++) {
791 desc->sg_req[i].len = period_len;
792
793 stm32_dma_clear_reg(&desc->sg_req[i].chan_reg);
794 desc->sg_req[i].chan_reg.dma_scr = chan->chan_reg.dma_scr;
795 desc->sg_req[i].chan_reg.dma_sfcr = chan->chan_reg.dma_sfcr;
796 desc->sg_req[i].chan_reg.dma_spar = chan->chan_reg.dma_spar;
797 desc->sg_req[i].chan_reg.dma_sm0ar = buf_addr;
798 desc->sg_req[i].chan_reg.dma_sm1ar = buf_addr;
799 desc->sg_req[i].chan_reg.dma_sndtr = nb_data_items;
800 buf_addr += period_len;
801 }
802
803 desc->num_sgs = num_periods;
804 desc->cyclic = true;
805
806 return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
807}
808
809static struct dma_async_tx_descriptor *stm32_dma_prep_dma_memcpy(
810 struct dma_chan *c, dma_addr_t dest,
811 dma_addr_t src, size_t len, unsigned long flags)
812{
813 struct stm32_dma_chan *chan = to_stm32_dma_chan(c);
814 u32 num_sgs;
815 struct stm32_dma_desc *desc;
816 size_t xfer_count, offset;
817 int i;
818
819 num_sgs = DIV_ROUND_UP(len, STM32_DMA_MAX_DATA_ITEMS);
820 desc = stm32_dma_alloc_desc(num_sgs);
821 if (!desc)
822 return NULL;
823
824 for (offset = 0, i = 0; offset < len; offset += xfer_count, i++) {
825 xfer_count = min_t(size_t, len - offset,
826 STM32_DMA_MAX_DATA_ITEMS);
827
828 desc->sg_req[i].len = xfer_count;
829
830 stm32_dma_clear_reg(&desc->sg_req[i].chan_reg);
831 desc->sg_req[i].chan_reg.dma_scr =
832 STM32_DMA_SCR_DIR(STM32_DMA_MEM_TO_MEM) |
833 STM32_DMA_SCR_MINC |
834 STM32_DMA_SCR_PINC |
835 STM32_DMA_SCR_TCIE |
836 STM32_DMA_SCR_TEIE;
837 desc->sg_req[i].chan_reg.dma_sfcr = STM32_DMA_SFCR_DMDIS |
838 STM32_DMA_SFCR_FTH(STM32_DMA_FIFO_THRESHOLD_FULL) |
839 STM32_DMA_SFCR_FEIE;
840 desc->sg_req[i].chan_reg.dma_spar = src + offset;
841 desc->sg_req[i].chan_reg.dma_sm0ar = dest + offset;
842 desc->sg_req[i].chan_reg.dma_sndtr = xfer_count;
843 }
844
845 desc->num_sgs = num_sgs;
846 desc->cyclic = false;
847
848 return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
849}
850
851static size_t stm32_dma_desc_residue(struct stm32_dma_chan *chan,
852 struct stm32_dma_desc *desc,
853 u32 next_sg)
854{
855 struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan);
856 u32 dma_scr, width, residue, count;
857 int i;
858
859 residue = 0;
860
861 for (i = next_sg; i < desc->num_sgs; i++)
862 residue += desc->sg_req[i].len;
863
864 if (next_sg != 0) {
865 dma_scr = stm32_dma_read(dmadev, STM32_DMA_SCR(chan->id));
866 width = STM32_DMA_SCR_PSIZE_GET(dma_scr);
867 count = stm32_dma_read(dmadev, STM32_DMA_SNDTR(chan->id));
868
869 residue += count << width;
870 }
871
872 return residue;
873}
874
875static enum dma_status stm32_dma_tx_status(struct dma_chan *c,
876 dma_cookie_t cookie,
877 struct dma_tx_state *state)
878{
879 struct stm32_dma_chan *chan = to_stm32_dma_chan(c);
880 struct virt_dma_desc *vdesc;
881 enum dma_status status;
882 unsigned long flags;
883 u32 residue;
884
885 status = dma_cookie_status(c, cookie, state);
886 if ((status == DMA_COMPLETE) || (!state))
887 return status;
888
889 spin_lock_irqsave(&chan->vchan.lock, flags);
890 vdesc = vchan_find_desc(&chan->vchan, cookie);
891 if (cookie == chan->desc->vdesc.tx.cookie) {
892 residue = stm32_dma_desc_residue(chan, chan->desc,
893 chan->next_sg);
894 } else if (vdesc) {
895 residue = stm32_dma_desc_residue(chan,
896 to_stm32_dma_desc(vdesc), 0);
897 } else {
898 residue = 0;
899 }
900
901 dma_set_residue(state, residue);
902
903 spin_unlock_irqrestore(&chan->vchan.lock, flags);
904
905 return status;
906}
907
908static int stm32_dma_alloc_chan_resources(struct dma_chan *c)
909{
910 struct stm32_dma_chan *chan = to_stm32_dma_chan(c);
911 struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan);
912 int ret;
913
914 chan->config_init = false;
915 ret = clk_prepare_enable(dmadev->clk);
916 if (ret < 0) {
917 dev_err(chan2dev(chan), "clk_prepare_enable failed: %d\n", ret);
918 return ret;
919 }
920
921 ret = stm32_dma_disable_chan(chan);
922 if (ret < 0)
923 clk_disable_unprepare(dmadev->clk);
924
925 return ret;
926}
927
928static void stm32_dma_free_chan_resources(struct dma_chan *c)
929{
930 struct stm32_dma_chan *chan = to_stm32_dma_chan(c);
931 struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan);
932 unsigned long flags;
933
934 dev_dbg(chan2dev(chan), "Freeing channel %d\n", chan->id);
935
936 if (chan->busy) {
937 spin_lock_irqsave(&chan->vchan.lock, flags);
938 stm32_dma_stop(chan);
939 chan->desc = NULL;
940 spin_unlock_irqrestore(&chan->vchan.lock, flags);
941 }
942
943 clk_disable_unprepare(dmadev->clk);
944
945 vchan_free_chan_resources(to_virt_chan(c));
946}
947
948static void stm32_dma_desc_free(struct virt_dma_desc *vdesc)
949{
950 kfree(container_of(vdesc, struct stm32_dma_desc, vdesc));
951}
952
e97adb49 953static void stm32_dma_set_config(struct stm32_dma_chan *chan,
d8b46839
CM		 954 struct stm32_dma_cfg *cfg)
955{
956 stm32_dma_clear_reg(&chan->chan_reg);
957
958 chan->chan_reg.dma_scr = cfg->stream_config & STM32_DMA_SCR_CFG_MASK;
959 chan->chan_reg.dma_scr |= STM32_DMA_SCR_REQ(cfg->request_line);
960
961 /* Enable Interrupts */
962 chan->chan_reg.dma_scr |= STM32_DMA_SCR_TEIE | STM32_DMA_SCR_TCIE;
963
964 chan->chan_reg.dma_sfcr = cfg->threshold & STM32_DMA_SFCR_FTH_MASK;
965}
966
967static struct dma_chan *stm32_dma_of_xlate(struct of_phandle_args *dma_spec,
968 struct of_dma *ofdma)
969{
970 struct stm32_dma_device *dmadev = ofdma->of_dma_data;
971 struct stm32_dma_cfg cfg;
972 struct stm32_dma_chan *chan;
973 struct dma_chan *c;
974
975 if (dma_spec->args_count < 3)
976 return NULL;
977
978 cfg.channel_id = dma_spec->args[0];
979 cfg.request_line = dma_spec->args[1];
980 cfg.stream_config = dma_spec->args[2];
981 cfg.threshold = 0;
982
983 if ((cfg.channel_id >= STM32_DMA_MAX_CHANNELS) || (cfg.request_line >=
984 STM32_DMA_MAX_REQUEST_ID))
985 return NULL;
986
987 if (dma_spec->args_count > 3)
988 cfg.threshold = dma_spec->args[3];
989
990 chan = &dmadev->chan[cfg.channel_id];
991
992 c = dma_get_slave_channel(&chan->vchan.chan);
993 if (c)
994 stm32_dma_set_config(chan, &cfg);
995
996 return c;
997}
998
999static const struct of_device_id stm32_dma_of_match[] = {
1000 { .compatible = "st,stm32-dma", },
1001 { /* sentinel */ },
1002};
1003MODULE_DEVICE_TABLE(of, stm32_dma_of_match);
1004
1005static int stm32_dma_probe(struct platform_device *pdev)
1006{
1007 struct stm32_dma_chan *chan;
1008 struct stm32_dma_device *dmadev;
1009 struct dma_device *dd;
1010 const struct of_device_id *match;
1011 struct resource *res;
1012 int i, ret;
1013
1014 match = of_match_device(stm32_dma_of_match, &pdev->dev);
1015 if (!match) {
1016 dev_err(&pdev->dev, "Error: No device match found\n");
1017 return -ENODEV;
1018 }
1019
1020 dmadev = devm_kzalloc(&pdev->dev, sizeof(*dmadev), GFP_KERNEL);
1021 if (!dmadev)
1022 return -ENOMEM;
1023
1024 dd = &dmadev->ddev;
1025
1026 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1027 dmadev->base = devm_ioremap_resource(&pdev->dev, res);
1028 if (IS_ERR(dmadev->base))
1029 return PTR_ERR(dmadev->base);
1030
1031 dmadev->clk = devm_clk_get(&pdev->dev, NULL);
1032 if (IS_ERR(dmadev->clk)) {
1033 dev_err(&pdev->dev, "Error: Missing controller clock\n");
1034 return PTR_ERR(dmadev->clk);
1035 }
1036
1037 dmadev->mem2mem = of_property_read_bool(pdev->dev.of_node,
1038 "st,mem2mem");
1039
1040 dmadev->rst = devm_reset_control_get(&pdev->dev, NULL);
1041 if (!IS_ERR(dmadev->rst)) {
1042 reset_control_assert(dmadev->rst);
1043 udelay(2);
1044 reset_control_deassert(dmadev->rst);
1045 }
1046
1047 dma_cap_set(DMA_SLAVE, dd->cap_mask);
1048 dma_cap_set(DMA_PRIVATE, dd->cap_mask);
1049 dma_cap_set(DMA_CYCLIC, dd->cap_mask);
1050 dd->device_alloc_chan_resources = stm32_dma_alloc_chan_resources;
1051 dd->device_free_chan_resources = stm32_dma_free_chan_resources;
1052 dd->device_tx_status = stm32_dma_tx_status;
1053 dd->device_issue_pending = stm32_dma_issue_pending;
1054 dd->device_prep_slave_sg = stm32_dma_prep_slave_sg;
1055 dd->device_prep_dma_cyclic = stm32_dma_prep_dma_cyclic;
1056 dd->device_config = stm32_dma_slave_config;
1057 dd->device_terminate_all = stm32_dma_terminate_all;
1058 dd->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1059 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1060 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
1061 dd->dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1062 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1063 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
1064 dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1065 dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1066 dd->dev = &pdev->dev;
1067 INIT_LIST_HEAD(&dd->channels);
1068
1069 if (dmadev->mem2mem) {
1070 dma_cap_set(DMA_MEMCPY, dd->cap_mask);
1071 dd->device_prep_dma_memcpy = stm32_dma_prep_dma_memcpy;
1072 dd->directions |= BIT(DMA_MEM_TO_MEM);
1073 }
1074
1075 for (i = 0; i < STM32_DMA_MAX_CHANNELS; i++) {
1076 chan = &dmadev->chan[i];
1077 chan->id = i;
1078 chan->vchan.desc_free = stm32_dma_desc_free;
1079 vchan_init(&chan->vchan, dd);
1080 }
1081
1082 ret = dma_async_device_register(dd);
1083 if (ret)
1084 return ret;
1085
1086 for (i = 0; i < STM32_DMA_MAX_CHANNELS; i++) {
1087 chan = &dmadev->chan[i];
1088 res = platform_get_resource(pdev, IORESOURCE_IRQ, i);
1089 if (!res) {
1090 ret = -EINVAL;
1091 dev_err(&pdev->dev, "No irq resource for chan %d\n", i);
1092 goto err_unregister;
1093 }
1094 chan->irq = res->start;
1095 ret = devm_request_irq(&pdev->dev, chan->irq,
1096 stm32_dma_chan_irq, 0,
1097 dev_name(chan2dev(chan)), chan);
1098 if (ret) {
1099 dev_err(&pdev->dev,
1100 "request_irq failed with err %d channel %d\n",
1101 ret, i);
1102 goto err_unregister;
1103 }
1104 }
1105
1106 ret = of_dma_controller_register(pdev->dev.of_node,
1107 stm32_dma_of_xlate, dmadev);
1108 if (ret < 0) {
1109 dev_err(&pdev->dev,
1110 "STM32 DMA DMA OF registration failed %d\n", ret);
1111 goto err_unregister;
1112 }
1113
1114 platform_set_drvdata(pdev, dmadev);
1115
1116 dev_info(&pdev->dev, "STM32 DMA driver registered\n");
1117
1118 return 0;
1119
1120err_unregister:
1121 dma_async_device_unregister(dd);
1122
1123 return ret;
1124}
1125
1126static struct platform_driver stm32_dma_driver = {
1127 .driver = {
1128 .name = "stm32-dma",
1129 .of_match_table = stm32_dma_of_match,
1130 },
1131};
1132
1133static int __init stm32_dma_init(void)
1134{
1135 return platform_driver_probe(&stm32_dma_driver, stm32_dma_probe);
1136}
1137subsys_initcall(stm32_dma_init);
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