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WIP FPC-III support
[linux/fpc-iii.git] / drivers / staging / ralink-gdma / ralink-gdma.c
blob655df317d0ee338b3861adc5b122559f968538b7
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2013, Lars-Peter Clausen <lars@metafoo.de>
4 * GDMA4740 DMAC support
5 */
6
7 #include <linux/dmaengine.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/err.h>
10 #include <linux/init.h>
11 #include <linux/list.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/slab.h>
15 #include <linux/spinlock.h>
16 #include <linux/irq.h>
17 #include <linux/of_dma.h>
18 #include <linux/reset.h>
19 #include <linux/of_device.h>
20
21 #include "virt-dma.h"
22
23 #define GDMA_REG_SRC_ADDR(x) (0x00 + (x) * 0x10)
24 #define GDMA_REG_DST_ADDR(x) (0x04 + (x) * 0x10)
25
26 #define GDMA_REG_CTRL0(x) (0x08 + (x) * 0x10)
27 #define GDMA_REG_CTRL0_TX_MASK 0xffff
28 #define GDMA_REG_CTRL0_TX_SHIFT 16
29 #define GDMA_REG_CTRL0_CURR_MASK 0xff
30 #define GDMA_REG_CTRL0_CURR_SHIFT 8
31 #define GDMA_REG_CTRL0_SRC_ADDR_FIXED BIT(7)
32 #define GDMA_REG_CTRL0_DST_ADDR_FIXED BIT(6)
33 #define GDMA_REG_CTRL0_BURST_MASK 0x7
34 #define GDMA_REG_CTRL0_BURST_SHIFT 3
35 #define GDMA_REG_CTRL0_DONE_INT BIT(2)
36 #define GDMA_REG_CTRL0_ENABLE BIT(1)
37 #define GDMA_REG_CTRL0_SW_MODE BIT(0)
38
39 #define GDMA_REG_CTRL1(x) (0x0c + (x) * 0x10)
40 #define GDMA_REG_CTRL1_SEG_MASK 0xf
41 #define GDMA_REG_CTRL1_SEG_SHIFT 22
42 #define GDMA_REG_CTRL1_REQ_MASK 0x3f
43 #define GDMA_REG_CTRL1_SRC_REQ_SHIFT 16
44 #define GDMA_REG_CTRL1_DST_REQ_SHIFT 8
45 #define GDMA_REG_CTRL1_NEXT_MASK 0x1f
46 #define GDMA_REG_CTRL1_NEXT_SHIFT 3
47 #define GDMA_REG_CTRL1_COHERENT BIT(2)
48 #define GDMA_REG_CTRL1_FAIL BIT(1)
49 #define GDMA_REG_CTRL1_MASK BIT(0)
50
51 #define GDMA_REG_UNMASK_INT 0x200
52 #define GDMA_REG_DONE_INT 0x204
53
54 #define GDMA_REG_GCT 0x220
55 #define GDMA_REG_GCT_CHAN_MASK 0x3
56 #define GDMA_REG_GCT_CHAN_SHIFT 3
57 #define GDMA_REG_GCT_VER_MASK 0x3
58 #define GDMA_REG_GCT_VER_SHIFT 1
59 #define GDMA_REG_GCT_ARBIT_RR BIT(0)
60
61 #define GDMA_REG_REQSTS 0x2a0
62 #define GDMA_REG_ACKSTS 0x2a4
63 #define GDMA_REG_FINSTS 0x2a8
64
65 /* for RT305X gdma registers */
66 #define GDMA_RT305X_CTRL0_REQ_MASK 0xf
67 #define GDMA_RT305X_CTRL0_SRC_REQ_SHIFT 12
68 #define GDMA_RT305X_CTRL0_DST_REQ_SHIFT 8
69
70 #define GDMA_RT305X_CTRL1_FAIL BIT(4)
71 #define GDMA_RT305X_CTRL1_NEXT_MASK 0x7
72 #define GDMA_RT305X_CTRL1_NEXT_SHIFT 1
73
74 #define GDMA_RT305X_STATUS_INT 0x80
75 #define GDMA_RT305X_STATUS_SIGNAL 0x84
76 #define GDMA_RT305X_GCT 0x88
77
78 /* for MT7621 gdma registers */
79 #define GDMA_REG_PERF_START(x) (0x230 + (x) * 0x8)
80 #define GDMA_REG_PERF_END(x) (0x234 + (x) * 0x8)
81
82 enum gdma_dma_transfer_size {
83 GDMA_TRANSFER_SIZE_4BYTE = 0,
84 GDMA_TRANSFER_SIZE_8BYTE = 1,
85 GDMA_TRANSFER_SIZE_16BYTE = 2,
86 GDMA_TRANSFER_SIZE_32BYTE = 3,
87 GDMA_TRANSFER_SIZE_64BYTE = 4,
88 };
89
90 struct gdma_dma_sg {
91 dma_addr_t src_addr;
92 dma_addr_t dst_addr;
93 u32 len;
94 };
95
96 struct gdma_dma_desc {
97 struct virt_dma_desc vdesc;
98
99 enum dma_transfer_direction direction;
100 bool cyclic;
101
102 u32 residue;
103 unsigned int num_sgs;
104 struct gdma_dma_sg sg[];
105 };
106
107 struct gdma_dmaengine_chan {
108 struct virt_dma_chan vchan;
109 unsigned int id;
110 unsigned int slave_id;
111
112 dma_addr_t fifo_addr;
113 enum gdma_dma_transfer_size burst_size;
114
115 struct gdma_dma_desc *desc;
116 unsigned int next_sg;
117 };
118
119 struct gdma_dma_dev {
120 struct dma_device ddev;
121 struct device_dma_parameters dma_parms;
122 struct gdma_data *data;
123 void __iomem *base;
124 struct tasklet_struct task;
125 volatile unsigned long chan_issued;
126 atomic_t cnt;
127
128 struct gdma_dmaengine_chan chan[];
129 };
130
131 struct gdma_data {
132 int chancnt;
133 u32 done_int_reg;
134 void (*init)(struct gdma_dma_dev *dma_dev);
135 int (*start_transfer)(struct gdma_dmaengine_chan *chan);
136 };
137
138 static struct gdma_dma_dev *gdma_dma_chan_get_dev(
139 struct gdma_dmaengine_chan *chan)
140 {
141 return container_of(chan->vchan.chan.device, struct gdma_dma_dev,
142 ddev);
143 }
144
145 static struct gdma_dmaengine_chan *to_gdma_dma_chan(struct dma_chan *c)
146 {
147 return container_of(c, struct gdma_dmaengine_chan, vchan.chan);
148 }
149
150 static struct gdma_dma_desc *to_gdma_dma_desc(struct virt_dma_desc *vdesc)
151 {
152 return container_of(vdesc, struct gdma_dma_desc, vdesc);
153 }
154
155 static inline uint32_t gdma_dma_read(struct gdma_dma_dev *dma_dev,
156 unsigned int reg)
157 {
158 return readl(dma_dev->base + reg);
159 }
160
161 static inline void gdma_dma_write(struct gdma_dma_dev *dma_dev,
162 unsigned int reg, uint32_t val)
163 {
164 writel(val, dma_dev->base + reg);
165 }
166
167 static enum gdma_dma_transfer_size gdma_dma_maxburst(u32 maxburst)
168 {
169 if (maxburst < 2)
170 return GDMA_TRANSFER_SIZE_4BYTE;
171 else if (maxburst < 4)
172 return GDMA_TRANSFER_SIZE_8BYTE;
173 else if (maxburst < 8)
174 return GDMA_TRANSFER_SIZE_16BYTE;
175 else if (maxburst < 16)
176 return GDMA_TRANSFER_SIZE_32BYTE;
177 else
178 return GDMA_TRANSFER_SIZE_64BYTE;
179 }
180
181 static int gdma_dma_config(struct dma_chan *c,
182 struct dma_slave_config *config)
183 {
184 struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
185 struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan);
186
187 if (config->device_fc) {
188 dev_err(dma_dev->ddev.dev, "not support flow controller\n");
189 return -EINVAL;
190 }
191
192 switch (config->direction) {
193 case DMA_MEM_TO_DEV:
194 if (config->dst_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) {
195 dev_err(dma_dev->ddev.dev, "only support 4 byte buswidth\n");
196 return -EINVAL;
197 }
198 chan->slave_id = config->slave_id;
199 chan->fifo_addr = config->dst_addr;
200 chan->burst_size = gdma_dma_maxburst(config->dst_maxburst);
201 break;
202 case DMA_DEV_TO_MEM:
203 if (config->src_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) {
204 dev_err(dma_dev->ddev.dev, "only support 4 byte buswidth\n");
205 return -EINVAL;
206 }
207 chan->slave_id = config->slave_id;
208 chan->fifo_addr = config->src_addr;
209 chan->burst_size = gdma_dma_maxburst(config->src_maxburst);
210 break;
211 default:
212 dev_err(dma_dev->ddev.dev, "direction type %d error\n",
213 config->direction);
214 return -EINVAL;
215 }
216
217 return 0;
218 }
219
220 static int gdma_dma_terminate_all(struct dma_chan *c)
221 {
222 struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
223 struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan);
224 unsigned long flags, timeout;
225 LIST_HEAD(head);
226 int i = 0;
227
228 spin_lock_irqsave(&chan->vchan.lock, flags);
229 chan->desc = NULL;
230 clear_bit(chan->id, &dma_dev->chan_issued);
231 vchan_get_all_descriptors(&chan->vchan, &head);
232 spin_unlock_irqrestore(&chan->vchan.lock, flags);
233
234 vchan_dma_desc_free_list(&chan->vchan, &head);
235
236 /* wait dma transfer complete */
237 timeout = jiffies + msecs_to_jiffies(5000);
238 while (gdma_dma_read(dma_dev, GDMA_REG_CTRL0(chan->id)) &
239 GDMA_REG_CTRL0_ENABLE) {
240 if (time_after_eq(jiffies, timeout)) {
241 dev_err(dma_dev->ddev.dev, "chan %d wait timeout\n",
242 chan->id);
243 /* restore to init value */
244 gdma_dma_write(dma_dev, GDMA_REG_CTRL0(chan->id), 0);
245 break;
246 }
247 cpu_relax();
248 i++;
249 }
250
251 if (i)
252 dev_dbg(dma_dev->ddev.dev, "terminate chan %d loops %d\n",
253 chan->id, i);
254
255 return 0;
256 }
257
258 static void rt305x_dump_reg(struct gdma_dma_dev *dma_dev, int id)
259 {
260 dev_dbg(dma_dev->ddev.dev, "chan %d, src %08x, dst %08x, ctr0 %08x, ctr1 %08x, intr %08x, signal %08x\n",
261 id,
262 gdma_dma_read(dma_dev, GDMA_REG_SRC_ADDR(id)),
263 gdma_dma_read(dma_dev, GDMA_REG_DST_ADDR(id)),
264 gdma_dma_read(dma_dev, GDMA_REG_CTRL0(id)),
265 gdma_dma_read(dma_dev, GDMA_REG_CTRL1(id)),
266 gdma_dma_read(dma_dev, GDMA_RT305X_STATUS_INT),
267 gdma_dma_read(dma_dev, GDMA_RT305X_STATUS_SIGNAL));
268 }
269
270 static int rt305x_gdma_start_transfer(struct gdma_dmaengine_chan *chan)
271 {
272 struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan);
273 dma_addr_t src_addr, dst_addr;
274 struct gdma_dma_sg *sg;
275 u32 ctrl0, ctrl1;
276
277 /* verify chan is already stopped */
278 ctrl0 = gdma_dma_read(dma_dev, GDMA_REG_CTRL0(chan->id));
279 if (unlikely(ctrl0 & GDMA_REG_CTRL0_ENABLE)) {
280 dev_err(dma_dev->ddev.dev, "chan %d is start(%08x).\n",
281 chan->id, ctrl0);
282 rt305x_dump_reg(dma_dev, chan->id);
283 return -EINVAL;
284 }
285
286 sg = &chan->desc->sg[chan->next_sg];
287 if (chan->desc->direction == DMA_MEM_TO_DEV) {
288 src_addr = sg->src_addr;
289 dst_addr = chan->fifo_addr;
290 ctrl0 = GDMA_REG_CTRL0_DST_ADDR_FIXED |
291 (8 << GDMA_RT305X_CTRL0_SRC_REQ_SHIFT) |
292 (chan->slave_id << GDMA_RT305X_CTRL0_DST_REQ_SHIFT);
293 } else if (chan->desc->direction == DMA_DEV_TO_MEM) {
294 src_addr = chan->fifo_addr;
295 dst_addr = sg->dst_addr;
296 ctrl0 = GDMA_REG_CTRL0_SRC_ADDR_FIXED |
297 (chan->slave_id << GDMA_RT305X_CTRL0_SRC_REQ_SHIFT) |
298 (8 << GDMA_RT305X_CTRL0_DST_REQ_SHIFT);
299 } else if (chan->desc->direction == DMA_MEM_TO_MEM) {
300 /*
301 * TODO: memcpy function have bugs. sometime it will copy
302 * more 8 bytes data when using dmatest verify.
303 */
304 src_addr = sg->src_addr;
305 dst_addr = sg->dst_addr;
306 ctrl0 = GDMA_REG_CTRL0_SW_MODE |
307 (8 << GDMA_REG_CTRL1_SRC_REQ_SHIFT) |
308 (8 << GDMA_REG_CTRL1_DST_REQ_SHIFT);
309 } else {
310 dev_err(dma_dev->ddev.dev, "direction type %d error\n",
311 chan->desc->direction);
312 return -EINVAL;
313 }
314
315 ctrl0 |= (sg->len << GDMA_REG_CTRL0_TX_SHIFT) |
316 (chan->burst_size << GDMA_REG_CTRL0_BURST_SHIFT) |
317 GDMA_REG_CTRL0_DONE_INT | GDMA_REG_CTRL0_ENABLE;
318 ctrl1 = chan->id << GDMA_REG_CTRL1_NEXT_SHIFT;
319
320 chan->next_sg++;
321 gdma_dma_write(dma_dev, GDMA_REG_SRC_ADDR(chan->id), src_addr);
322 gdma_dma_write(dma_dev, GDMA_REG_DST_ADDR(chan->id), dst_addr);
323 gdma_dma_write(dma_dev, GDMA_REG_CTRL1(chan->id), ctrl1);
324
325 /* make sure next_sg is update */
326 wmb();
327 gdma_dma_write(dma_dev, GDMA_REG_CTRL0(chan->id), ctrl0);
328
329 return 0;
330 }
331
332 static void rt3883_dump_reg(struct gdma_dma_dev *dma_dev, int id)
333 {
334 dev_dbg(dma_dev->ddev.dev, "chan %d, src %08x, dst %08x, ctr0 %08x, ctr1 %08x, unmask %08x, done %08x, req %08x, ack %08x, fin %08x\n",
335 id,
336 gdma_dma_read(dma_dev, GDMA_REG_SRC_ADDR(id)),
337 gdma_dma_read(dma_dev, GDMA_REG_DST_ADDR(id)),
338 gdma_dma_read(dma_dev, GDMA_REG_CTRL0(id)),
339 gdma_dma_read(dma_dev, GDMA_REG_CTRL1(id)),
340 gdma_dma_read(dma_dev, GDMA_REG_UNMASK_INT),
341 gdma_dma_read(dma_dev, GDMA_REG_DONE_INT),
342 gdma_dma_read(dma_dev, GDMA_REG_REQSTS),
343 gdma_dma_read(dma_dev, GDMA_REG_ACKSTS),
344 gdma_dma_read(dma_dev, GDMA_REG_FINSTS));
345 }
346
347 static int rt3883_gdma_start_transfer(struct gdma_dmaengine_chan *chan)
348 {
349 struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan);
350 dma_addr_t src_addr, dst_addr;
351 struct gdma_dma_sg *sg;
352 u32 ctrl0, ctrl1;
353
354 /* verify chan is already stopped */
355 ctrl0 = gdma_dma_read(dma_dev, GDMA_REG_CTRL0(chan->id));
356 if (unlikely(ctrl0 & GDMA_REG_CTRL0_ENABLE)) {
357 dev_err(dma_dev->ddev.dev, "chan %d is start(%08x).\n",
358 chan->id, ctrl0);
359 rt3883_dump_reg(dma_dev, chan->id);
360 return -EINVAL;
361 }
362
363 sg = &chan->desc->sg[chan->next_sg];
364 if (chan->desc->direction == DMA_MEM_TO_DEV) {
365 src_addr = sg->src_addr;
366 dst_addr = chan->fifo_addr;
367 ctrl0 = GDMA_REG_CTRL0_DST_ADDR_FIXED;
368 ctrl1 = (32 << GDMA_REG_CTRL1_SRC_REQ_SHIFT) |
369 (chan->slave_id << GDMA_REG_CTRL1_DST_REQ_SHIFT);
370 } else if (chan->desc->direction == DMA_DEV_TO_MEM) {
371 src_addr = chan->fifo_addr;
372 dst_addr = sg->dst_addr;
373 ctrl0 = GDMA_REG_CTRL0_SRC_ADDR_FIXED;
374 ctrl1 = (chan->slave_id << GDMA_REG_CTRL1_SRC_REQ_SHIFT) |
375 (32 << GDMA_REG_CTRL1_DST_REQ_SHIFT) |
376 GDMA_REG_CTRL1_COHERENT;
377 } else if (chan->desc->direction == DMA_MEM_TO_MEM) {
378 src_addr = sg->src_addr;
379 dst_addr = sg->dst_addr;
380 ctrl0 = GDMA_REG_CTRL0_SW_MODE;
381 ctrl1 = (32 << GDMA_REG_CTRL1_SRC_REQ_SHIFT) |
382 (32 << GDMA_REG_CTRL1_DST_REQ_SHIFT) |
383 GDMA_REG_CTRL1_COHERENT;
384 } else {
385 dev_err(dma_dev->ddev.dev, "direction type %d error\n",
386 chan->desc->direction);
387 return -EINVAL;
388 }
389
390 ctrl0 |= (sg->len << GDMA_REG_CTRL0_TX_SHIFT) |
391 (chan->burst_size << GDMA_REG_CTRL0_BURST_SHIFT) |
392 GDMA_REG_CTRL0_DONE_INT | GDMA_REG_CTRL0_ENABLE;
393 ctrl1 |= chan->id << GDMA_REG_CTRL1_NEXT_SHIFT;
394
395 chan->next_sg++;
396 gdma_dma_write(dma_dev, GDMA_REG_SRC_ADDR(chan->id), src_addr);
397 gdma_dma_write(dma_dev, GDMA_REG_DST_ADDR(chan->id), dst_addr);
398 gdma_dma_write(dma_dev, GDMA_REG_CTRL1(chan->id), ctrl1);
399
400 /* make sure next_sg is update */
401 wmb();
402 gdma_dma_write(dma_dev, GDMA_REG_CTRL0(chan->id), ctrl0);
403
404 return 0;
405 }
406
407 static inline int gdma_start_transfer(struct gdma_dma_dev *dma_dev,
408 struct gdma_dmaengine_chan *chan)
409 {
410 return dma_dev->data->start_transfer(chan);
411 }
412
413 static int gdma_next_desc(struct gdma_dmaengine_chan *chan)
414 {
415 struct virt_dma_desc *vdesc;
416
417 vdesc = vchan_next_desc(&chan->vchan);
418 if (!vdesc) {
419 chan->desc = NULL;
420 return 0;
421 }
422 chan->desc = to_gdma_dma_desc(vdesc);
423 chan->next_sg = 0;
424
425 return 1;
426 }
427
428 static void gdma_dma_chan_irq(struct gdma_dma_dev *dma_dev,
429 struct gdma_dmaengine_chan *chan)
430 {
431 struct gdma_dma_desc *desc;
432 unsigned long flags;
433 int chan_issued;
434
435 chan_issued = 0;
436 spin_lock_irqsave(&chan->vchan.lock, flags);
437 desc = chan->desc;
438 if (desc) {
439 if (desc->cyclic) {
440 vchan_cyclic_callback(&desc->vdesc);
441 if (chan->next_sg == desc->num_sgs)
442 chan->next_sg = 0;
443 chan_issued = 1;
444 } else {
445 desc->residue -= desc->sg[chan->next_sg - 1].len;
446 if (chan->next_sg == desc->num_sgs) {
447 list_del(&desc->vdesc.node);
448 vchan_cookie_complete(&desc->vdesc);
449 chan_issued = gdma_next_desc(chan);
450 } else {
451 chan_issued = 1;
452 }
453 }
454 } else {
455 dev_dbg(dma_dev->ddev.dev, "chan %d no desc to complete\n",
456 chan->id);
457 }
458 if (chan_issued)
459 set_bit(chan->id, &dma_dev->chan_issued);
460 spin_unlock_irqrestore(&chan->vchan.lock, flags);
461 }
462
463 static irqreturn_t gdma_dma_irq(int irq, void *devid)
464 {
465 struct gdma_dma_dev *dma_dev = devid;
466 u32 done, done_reg;
467 unsigned int i;
468
469 done_reg = dma_dev->data->done_int_reg;
470 done = gdma_dma_read(dma_dev, done_reg);
471 if (unlikely(!done))
472 return IRQ_NONE;
473
474 /* clean done bits */
475 gdma_dma_write(dma_dev, done_reg, done);
476
477 i = 0;
478 while (done) {
479 if (done & 0x1) {
480 gdma_dma_chan_irq(dma_dev, &dma_dev->chan[i]);
481 atomic_dec(&dma_dev->cnt);
482 }
483 done >>= 1;
484 i++;
485 }
486
487 /* start only have work to do */
488 if (dma_dev->chan_issued)
489 tasklet_schedule(&dma_dev->task);
490
491 return IRQ_HANDLED;
492 }
493
494 static void gdma_dma_issue_pending(struct dma_chan *c)
495 {
496 struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
497 struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan);
498 unsigned long flags;
499
500 spin_lock_irqsave(&chan->vchan.lock, flags);
501 if (vchan_issue_pending(&chan->vchan) && !chan->desc) {
502 if (gdma_next_desc(chan)) {
503 set_bit(chan->id, &dma_dev->chan_issued);
504 tasklet_schedule(&dma_dev->task);
505 } else {
506 dev_dbg(dma_dev->ddev.dev, "chan %d no desc to issue\n",
507 chan->id);
508 }
509 }
510 spin_unlock_irqrestore(&chan->vchan.lock, flags);
511 }
512
513 static struct dma_async_tx_descriptor *gdma_dma_prep_slave_sg(
514 struct dma_chan *c, struct scatterlist *sgl,
515 unsigned int sg_len, enum dma_transfer_direction direction,
516 unsigned long flags, void *context)
517 {
518 struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
519 struct gdma_dma_desc *desc;
520 struct scatterlist *sg;
521 unsigned int i;
522
523 desc = kzalloc(struct_size(desc, sg, sg_len), GFP_ATOMIC);
524 if (!desc) {
525 dev_err(c->device->dev, "alloc sg decs error\n");
526 return NULL;
527 }
528 desc->residue = 0;
529
530 for_each_sg(sgl, sg, sg_len, i) {
531 if (direction == DMA_MEM_TO_DEV) {
532 desc->sg[i].src_addr = sg_dma_address(sg);
533 } else if (direction == DMA_DEV_TO_MEM) {
534 desc->sg[i].dst_addr = sg_dma_address(sg);
535 } else {
536 dev_err(c->device->dev, "direction type %d error\n",
537 direction);
538 goto free_desc;
539 }
540
541 if (unlikely(sg_dma_len(sg) > GDMA_REG_CTRL0_TX_MASK)) {
542 dev_err(c->device->dev, "sg len too large %d\n",
543 sg_dma_len(sg));
544 goto free_desc;
545 }
546 desc->sg[i].len = sg_dma_len(sg);
547 desc->residue += sg_dma_len(sg);
548 }
549
550 desc->num_sgs = sg_len;
551 desc->direction = direction;
552 desc->cyclic = false;
553
554 return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
555
556 free_desc:
557 kfree(desc);
558 return NULL;
559 }
560
561 static struct dma_async_tx_descriptor *gdma_dma_prep_dma_memcpy(
562 struct dma_chan *c, dma_addr_t dest, dma_addr_t src,
563 size_t len, unsigned long flags)
564 {
565 struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
566 struct gdma_dma_desc *desc;
567 unsigned int num_periods, i;
568 size_t xfer_count;
569
570 if (len <= 0)
571 return NULL;
572
573 chan->burst_size = gdma_dma_maxburst(len >> 2);
574
575 xfer_count = GDMA_REG_CTRL0_TX_MASK;
576 num_periods = DIV_ROUND_UP(len, xfer_count);
577
578 desc = kzalloc(struct_size(desc, sg, num_periods), GFP_ATOMIC);
579 if (!desc) {
580 dev_err(c->device->dev, "alloc memcpy decs error\n");
581 return NULL;
582 }
583 desc->residue = len;
584
585 for (i = 0; i < num_periods; i++) {
586 desc->sg[i].src_addr = src;
587 desc->sg[i].dst_addr = dest;
588 if (len > xfer_count)
589 desc->sg[i].len = xfer_count;
590 else
591 desc->sg[i].len = len;
592 src += desc->sg[i].len;
593 dest += desc->sg[i].len;
594 len -= desc->sg[i].len;
595 }
596
597 desc->num_sgs = num_periods;
598 desc->direction = DMA_MEM_TO_MEM;
599 desc->cyclic = false;
600
601 return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
602 }
603
604 static struct dma_async_tx_descriptor *gdma_dma_prep_dma_cyclic(
605 struct dma_chan *c, dma_addr_t buf_addr, size_t buf_len,
606 size_t period_len, enum dma_transfer_direction direction,
607 unsigned long flags)
608 {
609 struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
610 struct gdma_dma_desc *desc;
611 unsigned int num_periods, i;
612
613 if (buf_len % period_len)
614 return NULL;
615
616 if (period_len > GDMA_REG_CTRL0_TX_MASK) {
617 dev_err(c->device->dev, "cyclic len too large %d\n",
618 period_len);
619 return NULL;
620 }
621
622 num_periods = buf_len / period_len;
623 desc = kzalloc(struct_size(desc, sg, num_periods), GFP_ATOMIC);
624 if (!desc) {
625 dev_err(c->device->dev, "alloc cyclic decs error\n");
626 return NULL;
627 }
628 desc->residue = buf_len;
629
630 for (i = 0; i < num_periods; i++) {
631 if (direction == DMA_MEM_TO_DEV) {
632 desc->sg[i].src_addr = buf_addr;
633 } else if (direction == DMA_DEV_TO_MEM) {
634 desc->sg[i].dst_addr = buf_addr;
635 } else {
636 dev_err(c->device->dev, "direction type %d error\n",
637 direction);
638 goto free_desc;
639 }
640 desc->sg[i].len = period_len;
641 buf_addr += period_len;
642 }
643
644 desc->num_sgs = num_periods;
645 desc->direction = direction;
646 desc->cyclic = true;
647
648 return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
649
650 free_desc:
651 kfree(desc);
652 return NULL;
653 }
654
655 static enum dma_status gdma_dma_tx_status(struct dma_chan *c,
656 dma_cookie_t cookie,
657 struct dma_tx_state *state)
658 {
659 struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
660 struct virt_dma_desc *vdesc;
661 enum dma_status status;
662 unsigned long flags;
663 struct gdma_dma_desc *desc;
664
665 status = dma_cookie_status(c, cookie, state);
666 if (status == DMA_COMPLETE || !state)
667 return status;
668
669 spin_lock_irqsave(&chan->vchan.lock, flags);
670 desc = chan->desc;
671 if (desc && (cookie == desc->vdesc.tx.cookie)) {
672 /*
673 * We never update edesc->residue in the cyclic case, so we
674 * can tell the remaining room to the end of the circular
675 * buffer.
676 */
677 if (desc->cyclic)
678 state->residue = desc->residue -
679 ((chan->next_sg - 1) * desc->sg[0].len);
680 else
681 state->residue = desc->residue;
682 } else {
683 vdesc = vchan_find_desc(&chan->vchan, cookie);
684 if (vdesc)
685 state->residue = to_gdma_dma_desc(vdesc)->residue;
686 }
687 spin_unlock_irqrestore(&chan->vchan.lock, flags);
688
689 dev_dbg(c->device->dev, "tx residue %d bytes\n", state->residue);
690
691 return status;
692 }
693
694 static void gdma_dma_free_chan_resources(struct dma_chan *c)
695 {
696 vchan_free_chan_resources(to_virt_chan(c));
697 }
698
699 static void gdma_dma_desc_free(struct virt_dma_desc *vdesc)
700 {
701 kfree(container_of(vdesc, struct gdma_dma_desc, vdesc));
702 }
703
704 static void gdma_dma_tasklet(struct tasklet_struct *t)
705 {
706 struct gdma_dma_dev *dma_dev = from_tasklet(dma_dev, t, task);
707 struct gdma_dmaengine_chan *chan;
708 static unsigned int last_chan;
709 unsigned int i, chan_mask;
710
711 /* record last chan to round robin all chans */
712 i = last_chan;
713 chan_mask = dma_dev->data->chancnt - 1;
714 do {
715 /*
716 * on mt7621. when verify with dmatest with all
717 * channel is enable. we need to limit only two
718 * channel is working at the same time. otherwise the
719 * data will have problem.
720 */
721 if (atomic_read(&dma_dev->cnt) >= 2) {
722 last_chan = i;
723 break;
724 }
725
726 if (test_and_clear_bit(i, &dma_dev->chan_issued)) {
727 chan = &dma_dev->chan[i];
728 if (chan->desc) {
729 atomic_inc(&dma_dev->cnt);
730 gdma_start_transfer(dma_dev, chan);
731 } else {
732 dev_dbg(dma_dev->ddev.dev,
733 "chan %d no desc to issue\n",
734 chan->id);
735 }
736 if (!dma_dev->chan_issued)
737 break;
738 }
739
740 i = (i + 1) & chan_mask;
741 } while (i != last_chan);
742 }
743
744 static void rt305x_gdma_init(struct gdma_dma_dev *dma_dev)
745 {
746 u32 gct;
747
748 /* all chans round robin */
749 gdma_dma_write(dma_dev, GDMA_RT305X_GCT, GDMA_REG_GCT_ARBIT_RR);
750
751 gct = gdma_dma_read(dma_dev, GDMA_RT305X_GCT);
752 dev_info(dma_dev->ddev.dev, "revision: %d, channels: %d\n",
753 (gct >> GDMA_REG_GCT_VER_SHIFT) & GDMA_REG_GCT_VER_MASK,
754 8 << ((gct >> GDMA_REG_GCT_CHAN_SHIFT) &
755 GDMA_REG_GCT_CHAN_MASK));
756 }
757
758 static void rt3883_gdma_init(struct gdma_dma_dev *dma_dev)
759 {
760 u32 gct;
761
762 /* all chans round robin */
763 gdma_dma_write(dma_dev, GDMA_REG_GCT, GDMA_REG_GCT_ARBIT_RR);
764
765 gct = gdma_dma_read(dma_dev, GDMA_REG_GCT);
766 dev_info(dma_dev->ddev.dev, "revision: %d, channels: %d\n",
767 (gct >> GDMA_REG_GCT_VER_SHIFT) & GDMA_REG_GCT_VER_MASK,
768 8 << ((gct >> GDMA_REG_GCT_CHAN_SHIFT) &
769 GDMA_REG_GCT_CHAN_MASK));
770 }
771
772 static struct gdma_data rt305x_gdma_data = {
773 .chancnt = 8,
774 .done_int_reg = GDMA_RT305X_STATUS_INT,
775 .init = rt305x_gdma_init,
776 .start_transfer = rt305x_gdma_start_transfer,
777 };
778
779 static struct gdma_data rt3883_gdma_data = {
780 .chancnt = 16,
781 .done_int_reg = GDMA_REG_DONE_INT,
782 .init = rt3883_gdma_init,
783 .start_transfer = rt3883_gdma_start_transfer,
784 };
785
786 static const struct of_device_id gdma_of_match_table[] = {
787 { .compatible = "ralink,rt305x-gdma", .data = &rt305x_gdma_data },
788 { .compatible = "ralink,rt3883-gdma", .data = &rt3883_gdma_data },
789 { },
790 };
791
792 static int gdma_dma_probe(struct platform_device *pdev)
793 {
794 const struct of_device_id *match;
795 struct gdma_dmaengine_chan *chan;
796 struct gdma_dma_dev *dma_dev;
797 struct dma_device *dd;
798 unsigned int i;
799 int ret;
800 int irq;
801 void __iomem *base;
802 struct gdma_data *data;
803
804 ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
805 if (ret)
806 return ret;
807
808 match = of_match_device(gdma_of_match_table, &pdev->dev);
809 if (!match)
810 return -EINVAL;
811 data = (struct gdma_data *)match->data;
812
813 dma_dev = devm_kzalloc(&pdev->dev,
814 struct_size(dma_dev, chan, data->chancnt),
815 GFP_KERNEL);
816 if (!dma_dev)
817 return -EINVAL;
818 dma_dev->data = data;
819
820 base = devm_platform_ioremap_resource(pdev, 0);
821 if (IS_ERR(base))
822 return PTR_ERR(base);
823 dma_dev->base = base;
824 tasklet_setup(&dma_dev->task, gdma_dma_tasklet);
825
826 irq = platform_get_irq(pdev, 0);
827 if (irq < 0)
828 return -EINVAL;
829 ret = devm_request_irq(&pdev->dev, irq, gdma_dma_irq,
830 0, dev_name(&pdev->dev), dma_dev);
831 if (ret) {
832 dev_err(&pdev->dev, "failed to request irq\n");
833 return ret;
834 }
835
836 device_reset(&pdev->dev);
837
838 dd = &dma_dev->ddev;
839 dma_cap_set(DMA_MEMCPY, dd->cap_mask);
840 dma_cap_set(DMA_SLAVE, dd->cap_mask);
841 dma_cap_set(DMA_CYCLIC, dd->cap_mask);
842 dd->device_free_chan_resources = gdma_dma_free_chan_resources;
843 dd->device_prep_dma_memcpy = gdma_dma_prep_dma_memcpy;
844 dd->device_prep_slave_sg = gdma_dma_prep_slave_sg;
845 dd->device_prep_dma_cyclic = gdma_dma_prep_dma_cyclic;
846 dd->device_config = gdma_dma_config;
847 dd->device_terminate_all = gdma_dma_terminate_all;
848 dd->device_tx_status = gdma_dma_tx_status;
849 dd->device_issue_pending = gdma_dma_issue_pending;
850
851 dd->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
852 dd->dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
853 dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
854 dd->residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
855
856 dd->dev = &pdev->dev;
857 dd->dev->dma_parms = &dma_dev->dma_parms;
858 dma_set_max_seg_size(dd->dev, GDMA_REG_CTRL0_TX_MASK);
859 INIT_LIST_HEAD(&dd->channels);
860
861 for (i = 0; i < data->chancnt; i++) {
862 chan = &dma_dev->chan[i];
863 chan->id = i;
864 chan->vchan.desc_free = gdma_dma_desc_free;
865 vchan_init(&chan->vchan, dd);
866 }
867
868 /* init hardware */
869 data->init(dma_dev);
870
871 ret = dma_async_device_register(dd);
872 if (ret) {
873 dev_err(&pdev->dev, "failed to register dma device\n");
874 return ret;
875 }
876
877 ret = of_dma_controller_register(pdev->dev.of_node,
878 of_dma_xlate_by_chan_id, dma_dev);
879 if (ret) {
880 dev_err(&pdev->dev, "failed to register of dma controller\n");
881 goto err_unregister;
882 }
883
884 platform_set_drvdata(pdev, dma_dev);
885
886 return 0;
887
888 err_unregister:
889 dma_async_device_unregister(dd);
890 return ret;
891 }
892
893 static int gdma_dma_remove(struct platform_device *pdev)
894 {
895 struct gdma_dma_dev *dma_dev = platform_get_drvdata(pdev);
896
897 tasklet_kill(&dma_dev->task);
898 of_dma_controller_free(pdev->dev.of_node);
899 dma_async_device_unregister(&dma_dev->ddev);
900
901 return 0;
902 }
903
904 static struct platform_driver gdma_dma_driver = {
905 .probe = gdma_dma_probe,
906 .remove = gdma_dma_remove,
907 .driver = {
908 .name = "gdma-rt2880",
909 .of_match_table = gdma_of_match_table,
910 },
911 };
912 module_platform_driver(gdma_dma_driver);
913
914 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
915 MODULE_DESCRIPTION("Ralink/MTK DMA driver");
916 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support