1 /*
2 * Texas Instruments CPDMA Driver
3 *
4 * Copyright (C) 2010 Texas Instruments
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation version 2.
9 *
10 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
11 * kind, whether express or implied; without even the implied warranty
12 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15 #include <linux/kernel.h>
16 #include <linux/spinlock.h>
17 #include <linux/device.h>
18 #include <linux/slab.h>
19 #include <linux/err.h>
20 #include <linux/dma-mapping.h>
21 #include <linux/io.h>
22
23 #include "davinci_cpdma.h"
24
25 /* DMA Registers */
26 #define CPDMA_TXIDVER 0x00
27 #define CPDMA_TXCONTROL 0x04
28 #define CPDMA_TXTEARDOWN 0x08
29 #define CPDMA_RXIDVER 0x10
30 #define CPDMA_RXCONTROL 0x14
31 #define CPDMA_SOFTRESET 0x1c
32 #define CPDMA_RXTEARDOWN 0x18
33 #define CPDMA_TXINTSTATRAW 0x80
34 #define CPDMA_TXINTSTATMASKED 0x84
35 #define CPDMA_TXINTMASKSET 0x88
36 #define CPDMA_TXINTMASKCLEAR 0x8c
37 #define CPDMA_MACINVECTOR 0x90
38 #define CPDMA_MACEOIVECTOR 0x94
39 #define CPDMA_RXINTSTATRAW 0xa0
40 #define CPDMA_RXINTSTATMASKED 0xa4
41 #define CPDMA_RXINTMASKSET 0xa8
42 #define CPDMA_RXINTMASKCLEAR 0xac
43 #define CPDMA_DMAINTSTATRAW 0xb0
44 #define CPDMA_DMAINTSTATMASKED 0xb4
45 #define CPDMA_DMAINTMASKSET 0xb8
46 #define CPDMA_DMAINTMASKCLEAR 0xbc
47 #define CPDMA_DMAINT_HOSTERR BIT(1)
48
49 /* the following exist only if has_ext_regs is set */
50 #define CPDMA_DMACONTROL 0x20
51 #define CPDMA_DMASTATUS 0x24
52 #define CPDMA_RXBUFFOFS 0x28
53 #define CPDMA_EM_CONTROL 0x2c
54
55 /* Descriptor mode bits */
56 #define CPDMA_DESC_SOP BIT(31)
57 #define CPDMA_DESC_EOP BIT(30)
58 #define CPDMA_DESC_OWNER BIT(29)
59 #define CPDMA_DESC_EOQ BIT(28)
60 #define CPDMA_DESC_TD_COMPLETE BIT(27)
61 #define CPDMA_DESC_PASS_CRC BIT(26)
62
63 #define CPDMA_TEARDOWN_VALUE 0xfffffffc
64
65 struct cpdma_desc {
66 /* hardware fields */
67 u32 hw_next;
68 u32 hw_buffer;
69 u32 hw_len;
70 u32 hw_mode;
71 /* software fields */
72 void *sw_token;
73 u32 sw_buffer;
74 u32 sw_len;
75 };
76
77 struct cpdma_desc_pool {
78 u32 phys;
79 u32 hw_addr;
80 void __iomem *iomap; /* ioremap map */
81 void *cpumap; /* dma_alloc map */
82 int desc_size, mem_size;
83 int num_desc, used_desc;
84 unsigned long *bitmap;
85 struct device *dev;
86 spinlock_t lock;
87 };
88
89 enum cpdma_state {
90 CPDMA_STATE_IDLE,
91 CPDMA_STATE_ACTIVE,
92 CPDMA_STATE_TEARDOWN,
93 };
94
95 const char *cpdma_state_str[] = { "idle", "active", "teardown" };
96
97 struct cpdma_ctlr {
98 enum cpdma_state state;
99 struct cpdma_params params;
100 struct device *dev;
101 struct cpdma_desc_pool *pool;
102 spinlock_t lock;
103 struct cpdma_chan *channels[2 * CPDMA_MAX_CHANNELS];
104 };
105
106 struct cpdma_chan {
107 enum cpdma_state state;
108 struct cpdma_ctlr *ctlr;
109 int chan_num;
110 spinlock_t lock;
111 struct cpdma_desc __iomem *head, *tail;
112 int count;
113 void __iomem *hdp, *cp, *rxfree;
114 u32 mask;
115 cpdma_handler_fn handler;
116 enum dma_data_direction dir;
117 struct cpdma_chan_stats stats;
118 /* offsets into dmaregs */
119 int int_set, int_clear, td;
120 };
121
122 /* The following make access to common cpdma_ctlr params more readable */
123 #define dmaregs params.dmaregs
124 #define num_chan params.num_chan
125
126 /* various accessors */
127 #define dma_reg_read(ctlr, ofs) __raw_readl((ctlr)->dmaregs + (ofs))
128 #define chan_read(chan, fld) __raw_readl((chan)->fld)
129 #define desc_read(desc, fld) __raw_readl(&(desc)->fld)
130 #define dma_reg_write(ctlr, ofs, v) __raw_writel(v, (ctlr)->dmaregs + (ofs))
131 #define chan_write(chan, fld, v) __raw_writel(v, (chan)->fld)
132 #define desc_write(desc, fld, v) __raw_writel((u32)(v), &(desc)->fld)
133
134 /*
135 * Utility constructs for a cpdma descriptor pool. Some devices (e.g. davinci
136 * emac) have dedicated on-chip memory for these descriptors. Some other
137 * devices (e.g. cpsw switches) use plain old memory. Descriptor pools
138 * abstract out these details
139 */
140 static struct cpdma_desc_pool *
cpdma_desc_pool_create(struct device * dev,u32 phys,u32 hw_addr,int size,int align)141 cpdma_desc_pool_create(struct device *dev, u32 phys, u32 hw_addr,
142 int size, int align)
143 {
144 int bitmap_size;
145 struct cpdma_desc_pool *pool;
146
147 pool = kzalloc(sizeof(*pool), GFP_KERNEL);
148 if (!pool)
149 return NULL;
150
151 spin_lock_init(&pool->lock);
152
153 pool->dev = dev;
154 pool->mem_size = size;
155 pool->desc_size = ALIGN(sizeof(struct cpdma_desc), align);
156 pool->num_desc = size / pool->desc_size;
157
158 bitmap_size = (pool->num_desc / BITS_PER_LONG) * sizeof(long);
159 pool->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
160 if (!pool->bitmap)
161 goto fail;
162
163 if (phys) {
164 pool->phys = phys;
165 pool->iomap = ioremap(phys, size);
166 pool->hw_addr = hw_addr;
167 } else {
168 pool->cpumap = dma_alloc_coherent(dev, size, &pool->phys,
169 GFP_KERNEL);
170 pool->iomap = pool->cpumap;
171 pool->hw_addr = pool->phys;
172 }
173
174 if (pool->iomap)
175 return pool;
176
177 fail:
178 kfree(pool->bitmap);
179 kfree(pool);
180 return NULL;
181 }
182
cpdma_desc_pool_destroy(struct cpdma_desc_pool * pool)183 static void cpdma_desc_pool_destroy(struct cpdma_desc_pool *pool)
184 {
185 unsigned long flags;
186
187 if (!pool)
188 return;
189
190 spin_lock_irqsave(&pool->lock, flags);
191 WARN_ON(pool->used_desc);
192 kfree(pool->bitmap);
193 if (pool->cpumap) {
194 dma_free_coherent(pool->dev, pool->mem_size, pool->cpumap,
195 pool->phys);
196 } else {
197 iounmap(pool->iomap);
198 }
199 spin_unlock_irqrestore(&pool->lock, flags);
200 kfree(pool);
201 }
202
desc_phys(struct cpdma_desc_pool * pool,struct cpdma_desc __iomem * desc)203 static inline dma_addr_t desc_phys(struct cpdma_desc_pool *pool,
204 struct cpdma_desc __iomem *desc)
205 {
206 if (!desc)
207 return 0;
208 return pool->hw_addr + (__force dma_addr_t)desc -
209 (__force dma_addr_t)pool->iomap;
210 }
211
212 static inline struct cpdma_desc __iomem *
desc_from_phys(struct cpdma_desc_pool * pool,dma_addr_t dma)213 desc_from_phys(struct cpdma_desc_pool *pool, dma_addr_t dma)
214 {
215 return dma ? pool->iomap + dma - pool->hw_addr : NULL;
216 }
217
218 static struct cpdma_desc __iomem *
cpdma_desc_alloc(struct cpdma_desc_pool * pool,int num_desc)219 cpdma_desc_alloc(struct cpdma_desc_pool *pool, int num_desc)
220 {
221 unsigned long flags;
222 int index;
223 struct cpdma_desc __iomem *desc = NULL;
224
225 spin_lock_irqsave(&pool->lock, flags);
226
227 index = bitmap_find_next_zero_area(pool->bitmap, pool->num_desc, 0,
228 num_desc, 0);
229 if (index < pool->num_desc) {
230 bitmap_set(pool->bitmap, index, num_desc);
231 desc = pool->iomap + pool->desc_size * index;
232 pool->used_desc++;
233 }
234
235 spin_unlock_irqrestore(&pool->lock, flags);
236 return desc;
237 }
238
cpdma_desc_free(struct cpdma_desc_pool * pool,struct cpdma_desc __iomem * desc,int num_desc)239 static void cpdma_desc_free(struct cpdma_desc_pool *pool,
240 struct cpdma_desc __iomem *desc, int num_desc)
241 {
242 unsigned long flags, index;
243
244 index = ((unsigned long)desc - (unsigned long)pool->iomap) /
245 pool->desc_size;
246 spin_lock_irqsave(&pool->lock, flags);
247 bitmap_clear(pool->bitmap, index, num_desc);
248 pool->used_desc--;
249 spin_unlock_irqrestore(&pool->lock, flags);
250 }
251
cpdma_ctlr_create(struct cpdma_params * params)252 struct cpdma_ctlr *cpdma_ctlr_create(struct cpdma_params *params)
253 {
254 struct cpdma_ctlr *ctlr;
255
256 ctlr = kzalloc(sizeof(*ctlr), GFP_KERNEL);
257 if (!ctlr)
258 return NULL;
259
260 ctlr->state = CPDMA_STATE_IDLE;
261 ctlr->params = *params;
262 ctlr->dev = params->dev;
263 spin_lock_init(&ctlr->lock);
264
265 ctlr->pool = cpdma_desc_pool_create(ctlr->dev,
266 ctlr->params.desc_mem_phys,
267 ctlr->params.desc_hw_addr,
268 ctlr->params.desc_mem_size,
269 ctlr->params.desc_align);
270 if (!ctlr->pool) {
271 kfree(ctlr);
272 return NULL;
273 }
274
275 if (WARN_ON(ctlr->num_chan > CPDMA_MAX_CHANNELS))
276 ctlr->num_chan = CPDMA_MAX_CHANNELS;
277 return ctlr;
278 }
279
cpdma_ctlr_start(struct cpdma_ctlr * ctlr)280 int cpdma_ctlr_start(struct cpdma_ctlr *ctlr)
281 {
282 unsigned long flags;
283 int i;
284
285 spin_lock_irqsave(&ctlr->lock, flags);
286 if (ctlr->state != CPDMA_STATE_IDLE) {
287 spin_unlock_irqrestore(&ctlr->lock, flags);
288 return -EBUSY;
289 }
290
291 if (ctlr->params.has_soft_reset) {
292 unsigned long timeout = jiffies + HZ/10;
293
294 dma_reg_write(ctlr, CPDMA_SOFTRESET, 1);
295 while (time_before(jiffies, timeout)) {
296 if (dma_reg_read(ctlr, CPDMA_SOFTRESET) == 0)
297 break;
298 }
299 WARN_ON(!time_before(jiffies, timeout));
300 }
301
302 for (i = 0; i < ctlr->num_chan; i++) {
303 __raw_writel(0, ctlr->params.txhdp + 4 * i);
304 __raw_writel(0, ctlr->params.rxhdp + 4 * i);
305 __raw_writel(0, ctlr->params.txcp + 4 * i);
306 __raw_writel(0, ctlr->params.rxcp + 4 * i);
307 }
308
309 dma_reg_write(ctlr, CPDMA_RXINTMASKCLEAR, 0xffffffff);
310 dma_reg_write(ctlr, CPDMA_TXINTMASKCLEAR, 0xffffffff);
311
312 dma_reg_write(ctlr, CPDMA_TXCONTROL, 1);
313 dma_reg_write(ctlr, CPDMA_RXCONTROL, 1);
314
315 ctlr->state = CPDMA_STATE_ACTIVE;
316
317 for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
318 if (ctlr->channels[i])
319 cpdma_chan_start(ctlr->channels[i]);
320 }
321 spin_unlock_irqrestore(&ctlr->lock, flags);
322 return 0;
323 }
324
cpdma_ctlr_stop(struct cpdma_ctlr * ctlr)325 int cpdma_ctlr_stop(struct cpdma_ctlr *ctlr)
326 {
327 unsigned long flags;
328 int i;
329
330 spin_lock_irqsave(&ctlr->lock, flags);
331 if (ctlr->state != CPDMA_STATE_ACTIVE) {
332 spin_unlock_irqrestore(&ctlr->lock, flags);
333 return -EINVAL;
334 }
335
336 ctlr->state = CPDMA_STATE_TEARDOWN;
337
338 for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
339 if (ctlr->channels[i])
340 cpdma_chan_stop(ctlr->channels[i]);
341 }
342
343 dma_reg_write(ctlr, CPDMA_RXINTMASKCLEAR, 0xffffffff);
344 dma_reg_write(ctlr, CPDMA_TXINTMASKCLEAR, 0xffffffff);
345
346 dma_reg_write(ctlr, CPDMA_TXCONTROL, 0);
347 dma_reg_write(ctlr, CPDMA_RXCONTROL, 0);
348
349 ctlr->state = CPDMA_STATE_IDLE;
350
351 spin_unlock_irqrestore(&ctlr->lock, flags);
352 return 0;
353 }
354
cpdma_ctlr_dump(struct cpdma_ctlr * ctlr)355 int cpdma_ctlr_dump(struct cpdma_ctlr *ctlr)
356 {
357 struct device *dev = ctlr->dev;
358 unsigned long flags;
359 int i;
360
361 spin_lock_irqsave(&ctlr->lock, flags);
362
363 dev_info(dev, "CPDMA: state: %s", cpdma_state_str[ctlr->state]);
364
365 dev_info(dev, "CPDMA: txidver: %x",
366 dma_reg_read(ctlr, CPDMA_TXIDVER));
367 dev_info(dev, "CPDMA: txcontrol: %x",
368 dma_reg_read(ctlr, CPDMA_TXCONTROL));
369 dev_info(dev, "CPDMA: txteardown: %x",
370 dma_reg_read(ctlr, CPDMA_TXTEARDOWN));
371 dev_info(dev, "CPDMA: rxidver: %x",
372 dma_reg_read(ctlr, CPDMA_RXIDVER));
373 dev_info(dev, "CPDMA: rxcontrol: %x",
374 dma_reg_read(ctlr, CPDMA_RXCONTROL));
375 dev_info(dev, "CPDMA: softreset: %x",
376 dma_reg_read(ctlr, CPDMA_SOFTRESET));
377 dev_info(dev, "CPDMA: rxteardown: %x",
378 dma_reg_read(ctlr, CPDMA_RXTEARDOWN));
379 dev_info(dev, "CPDMA: txintstatraw: %x",
380 dma_reg_read(ctlr, CPDMA_TXINTSTATRAW));
381 dev_info(dev, "CPDMA: txintstatmasked: %x",
382 dma_reg_read(ctlr, CPDMA_TXINTSTATMASKED));
383 dev_info(dev, "CPDMA: txintmaskset: %x",
384 dma_reg_read(ctlr, CPDMA_TXINTMASKSET));
385 dev_info(dev, "CPDMA: txintmaskclear: %x",
386 dma_reg_read(ctlr, CPDMA_TXINTMASKCLEAR));
387 dev_info(dev, "CPDMA: macinvector: %x",
388 dma_reg_read(ctlr, CPDMA_MACINVECTOR));
389 dev_info(dev, "CPDMA: maceoivector: %x",
390 dma_reg_read(ctlr, CPDMA_MACEOIVECTOR));
391 dev_info(dev, "CPDMA: rxintstatraw: %x",
392 dma_reg_read(ctlr, CPDMA_RXINTSTATRAW));
393 dev_info(dev, "CPDMA: rxintstatmasked: %x",
394 dma_reg_read(ctlr, CPDMA_RXINTSTATMASKED));
395 dev_info(dev, "CPDMA: rxintmaskset: %x",
396 dma_reg_read(ctlr, CPDMA_RXINTMASKSET));
397 dev_info(dev, "CPDMA: rxintmaskclear: %x",
398 dma_reg_read(ctlr, CPDMA_RXINTMASKCLEAR));
399 dev_info(dev, "CPDMA: dmaintstatraw: %x",
400 dma_reg_read(ctlr, CPDMA_DMAINTSTATRAW));
401 dev_info(dev, "CPDMA: dmaintstatmasked: %x",
402 dma_reg_read(ctlr, CPDMA_DMAINTSTATMASKED));
403 dev_info(dev, "CPDMA: dmaintmaskset: %x",
404 dma_reg_read(ctlr, CPDMA_DMAINTMASKSET));
405 dev_info(dev, "CPDMA: dmaintmaskclear: %x",
406 dma_reg_read(ctlr, CPDMA_DMAINTMASKCLEAR));
407
408 if (!ctlr->params.has_ext_regs) {
409 dev_info(dev, "CPDMA: dmacontrol: %x",
410 dma_reg_read(ctlr, CPDMA_DMACONTROL));
411 dev_info(dev, "CPDMA: dmastatus: %x",
412 dma_reg_read(ctlr, CPDMA_DMASTATUS));
413 dev_info(dev, "CPDMA: rxbuffofs: %x",
414 dma_reg_read(ctlr, CPDMA_RXBUFFOFS));
415 }
416
417 for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++)
418 if (ctlr->channels[i])
419 cpdma_chan_dump(ctlr->channels[i]);
420
421 spin_unlock_irqrestore(&ctlr->lock, flags);
422 return 0;
423 }
424
cpdma_ctlr_destroy(struct cpdma_ctlr * ctlr)425 int cpdma_ctlr_destroy(struct cpdma_ctlr *ctlr)
426 {
427 unsigned long flags;
428 int ret = 0, i;
429
430 if (!ctlr)
431 return -EINVAL;
432
433 spin_lock_irqsave(&ctlr->lock, flags);
434 if (ctlr->state != CPDMA_STATE_IDLE)
435 cpdma_ctlr_stop(ctlr);
436
437 for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
438 if (ctlr->channels[i])
439 cpdma_chan_destroy(ctlr->channels[i]);
440 }
441
442 cpdma_desc_pool_destroy(ctlr->pool);
443 spin_unlock_irqrestore(&ctlr->lock, flags);
444 kfree(ctlr);
445 return ret;
446 }
447
cpdma_ctlr_int_ctrl(struct cpdma_ctlr * ctlr,bool enable)448 int cpdma_ctlr_int_ctrl(struct cpdma_ctlr *ctlr, bool enable)
449 {
450 unsigned long flags;
451 int i, reg;
452
453 spin_lock_irqsave(&ctlr->lock, flags);
454 if (ctlr->state != CPDMA_STATE_ACTIVE) {
455 spin_unlock_irqrestore(&ctlr->lock, flags);
456 return -EINVAL;
457 }
458
459 reg = enable ? CPDMA_DMAINTMASKSET : CPDMA_DMAINTMASKCLEAR;
460 dma_reg_write(ctlr, reg, CPDMA_DMAINT_HOSTERR);
461
462 for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
463 if (ctlr->channels[i])
464 cpdma_chan_int_ctrl(ctlr->channels[i], enable);
465 }
466
467 spin_unlock_irqrestore(&ctlr->lock, flags);
468 return 0;
469 }
470
cpdma_ctlr_eoi(struct cpdma_ctlr * ctlr)471 void cpdma_ctlr_eoi(struct cpdma_ctlr *ctlr)
472 {
473 dma_reg_write(ctlr, CPDMA_MACEOIVECTOR, 0);
474 }
475
cpdma_chan_create(struct cpdma_ctlr * ctlr,int chan_num,cpdma_handler_fn handler)476 struct cpdma_chan *cpdma_chan_create(struct cpdma_ctlr *ctlr, int chan_num,
477 cpdma_handler_fn handler)
478 {
479 struct cpdma_chan *chan;
480 int ret, offset = (chan_num % CPDMA_MAX_CHANNELS) * 4;
481 unsigned long flags;
482
483 if (__chan_linear(chan_num) >= ctlr->num_chan)
484 return NULL;
485
486 ret = -ENOMEM;
487 chan = kzalloc(sizeof(*chan), GFP_KERNEL);
488 if (!chan)
489 goto err_chan_alloc;
490
491 spin_lock_irqsave(&ctlr->lock, flags);
492 ret = -EBUSY;
493 if (ctlr->channels[chan_num])
494 goto err_chan_busy;
495
496 chan->ctlr = ctlr;
497 chan->state = CPDMA_STATE_IDLE;
498 chan->chan_num = chan_num;
499 chan->handler = handler;
500
501 if (is_rx_chan(chan)) {
502 chan->hdp = ctlr->params.rxhdp + offset;
503 chan->cp = ctlr->params.rxcp + offset;
504 chan->rxfree = ctlr->params.rxfree + offset;
505 chan->int_set = CPDMA_RXINTMASKSET;
506 chan->int_clear = CPDMA_RXINTMASKCLEAR;
507 chan->td = CPDMA_RXTEARDOWN;
508 chan->dir = DMA_FROM_DEVICE;
509 } else {
510 chan->hdp = ctlr->params.txhdp + offset;
511 chan->cp = ctlr->params.txcp + offset;
512 chan->int_set = CPDMA_TXINTMASKSET;
513 chan->int_clear = CPDMA_TXINTMASKCLEAR;
514 chan->td = CPDMA_TXTEARDOWN;
515 chan->dir = DMA_TO_DEVICE;
516 }
517 chan->mask = BIT(chan_linear(chan));
518
519 spin_lock_init(&chan->lock);
520
521 ctlr->channels[chan_num] = chan;
522 spin_unlock_irqrestore(&ctlr->lock, flags);
523 return chan;
524
525 err_chan_busy:
526 spin_unlock_irqrestore(&ctlr->lock, flags);
527 kfree(chan);
528 err_chan_alloc:
529 return ERR_PTR(ret);
530 }
531
cpdma_chan_destroy(struct cpdma_chan * chan)532 int cpdma_chan_destroy(struct cpdma_chan *chan)
533 {
534 struct cpdma_ctlr *ctlr = chan->ctlr;
535 unsigned long flags;
536
537 if (!chan)
538 return -EINVAL;
539
540 spin_lock_irqsave(&ctlr->lock, flags);
541 if (chan->state != CPDMA_STATE_IDLE)
542 cpdma_chan_stop(chan);
543 ctlr->channels[chan->chan_num] = NULL;
544 spin_unlock_irqrestore(&ctlr->lock, flags);
545 kfree(chan);
546 return 0;
547 }
548
cpdma_chan_get_stats(struct cpdma_chan * chan,struct cpdma_chan_stats * stats)549 int cpdma_chan_get_stats(struct cpdma_chan *chan,
550 struct cpdma_chan_stats *stats)
551 {
552 unsigned long flags;
553 if (!chan)
554 return -EINVAL;
555 spin_lock_irqsave(&chan->lock, flags);
556 memcpy(stats, &chan->stats, sizeof(*stats));
557 spin_unlock_irqrestore(&chan->lock, flags);
558 return 0;
559 }
560
cpdma_chan_dump(struct cpdma_chan * chan)561 int cpdma_chan_dump(struct cpdma_chan *chan)
562 {
563 unsigned long flags;
564 struct device *dev = chan->ctlr->dev;
565
566 spin_lock_irqsave(&chan->lock, flags);
567
568 dev_info(dev, "channel %d (%s %d) state %s",
569 chan->chan_num, is_rx_chan(chan) ? "rx" : "tx",
570 chan_linear(chan), cpdma_state_str[chan->state]);
571 dev_info(dev, "\thdp: %x\n", chan_read(chan, hdp));
572 dev_info(dev, "\tcp: %x\n", chan_read(chan, cp));
573 if (chan->rxfree) {
574 dev_info(dev, "\trxfree: %x\n",
575 chan_read(chan, rxfree));
576 }
577
578 dev_info(dev, "\tstats head_enqueue: %d\n",
579 chan->stats.head_enqueue);
580 dev_info(dev, "\tstats tail_enqueue: %d\n",
581 chan->stats.tail_enqueue);
582 dev_info(dev, "\tstats pad_enqueue: %d\n",
583 chan->stats.pad_enqueue);
584 dev_info(dev, "\tstats misqueued: %d\n",
585 chan->stats.misqueued);
586 dev_info(dev, "\tstats desc_alloc_fail: %d\n",
587 chan->stats.desc_alloc_fail);
588 dev_info(dev, "\tstats pad_alloc_fail: %d\n",
589 chan->stats.pad_alloc_fail);
590 dev_info(dev, "\tstats runt_receive_buff: %d\n",
591 chan->stats.runt_receive_buff);
592 dev_info(dev, "\tstats runt_transmit_buff: %d\n",
593 chan->stats.runt_transmit_buff);
594 dev_info(dev, "\tstats empty_dequeue: %d\n",
595 chan->stats.empty_dequeue);
596 dev_info(dev, "\tstats busy_dequeue: %d\n",
597 chan->stats.busy_dequeue);
598 dev_info(dev, "\tstats good_dequeue: %d\n",
599 chan->stats.good_dequeue);
600 dev_info(dev, "\tstats requeue: %d\n",
601 chan->stats.requeue);
602 dev_info(dev, "\tstats teardown_dequeue: %d\n",
603 chan->stats.teardown_dequeue);
604
605 spin_unlock_irqrestore(&chan->lock, flags);
606 return 0;
607 }
608
__cpdma_chan_submit(struct cpdma_chan * chan,struct cpdma_desc __iomem * desc)609 static void __cpdma_chan_submit(struct cpdma_chan *chan,
610 struct cpdma_desc __iomem *desc)
611 {
612 struct cpdma_ctlr *ctlr = chan->ctlr;
613 struct cpdma_desc __iomem *prev = chan->tail;
614 struct cpdma_desc_pool *pool = ctlr->pool;
615 dma_addr_t desc_dma;
616 u32 mode;
617
618 desc_dma = desc_phys(pool, desc);
619
620 /* simple case - idle channel */
621 if (!chan->head) {
622 chan->stats.head_enqueue++;
623 chan->head = desc;
624 chan->tail = desc;
625 if (chan->state == CPDMA_STATE_ACTIVE)
626 chan_write(chan, hdp, desc_dma);
627 return;
628 }
629
630 /* first chain the descriptor at the tail of the list */
631 desc_write(prev, hw_next, desc_dma);
632 chan->tail = desc;
633 chan->stats.tail_enqueue++;
634
635 /* next check if EOQ has been triggered already */
636 mode = desc_read(prev, hw_mode);
637 if (((mode & (CPDMA_DESC_EOQ | CPDMA_DESC_OWNER)) == CPDMA_DESC_EOQ) &&
638 (chan->state == CPDMA_STATE_ACTIVE)) {
639 desc_write(prev, hw_mode, mode & ~CPDMA_DESC_EOQ);
640 chan_write(chan, hdp, desc_dma);
641 chan->stats.misqueued++;
642 }
643 }
644
cpdma_chan_submit(struct cpdma_chan * chan,void * token,void * data,int len,gfp_t gfp_mask)645 int cpdma_chan_submit(struct cpdma_chan *chan, void *token, void *data,
646 int len, gfp_t gfp_mask)
647 {
648 struct cpdma_ctlr *ctlr = chan->ctlr;
649 struct cpdma_desc __iomem *desc;
650 dma_addr_t buffer;
651 unsigned long flags;
652 u32 mode;
653 int ret = 0;
654
655 spin_lock_irqsave(&chan->lock, flags);
656
657 if (chan->state == CPDMA_STATE_TEARDOWN) {
658 ret = -EINVAL;
659 goto unlock_ret;
660 }
661
662 desc = cpdma_desc_alloc(ctlr->pool, 1);
663 if (!desc) {
664 chan->stats.desc_alloc_fail++;
665 ret = -ENOMEM;
666 goto unlock_ret;
667 }
668
669 if (len < ctlr->params.min_packet_size) {
670 len = ctlr->params.min_packet_size;
671 chan->stats.runt_transmit_buff++;
672 }
673
674 buffer = dma_map_single(ctlr->dev, data, len, chan->dir);
675 mode = CPDMA_DESC_OWNER | CPDMA_DESC_SOP | CPDMA_DESC_EOP;
676
677 desc_write(desc, hw_next, 0);
678 desc_write(desc, hw_buffer, buffer);
679 desc_write(desc, hw_len, len);
680 desc_write(desc, hw_mode, mode | len);
681 desc_write(desc, sw_token, token);
682 desc_write(desc, sw_buffer, buffer);
683 desc_write(desc, sw_len, len);
684
685 __cpdma_chan_submit(chan, desc);
686
687 if (chan->state == CPDMA_STATE_ACTIVE && chan->rxfree)
688 chan_write(chan, rxfree, 1);
689
690 chan->count++;
691
692 unlock_ret:
693 spin_unlock_irqrestore(&chan->lock, flags);
694 return ret;
695 }
696
__cpdma_chan_free(struct cpdma_chan * chan,struct cpdma_desc __iomem * desc,int outlen,int status)697 static void __cpdma_chan_free(struct cpdma_chan *chan,
698 struct cpdma_desc __iomem *desc,
699 int outlen, int status)
700 {
701 struct cpdma_ctlr *ctlr = chan->ctlr;
702 struct cpdma_desc_pool *pool = ctlr->pool;
703 dma_addr_t buff_dma;
704 int origlen;
705 void *token;
706
707 token = (void *)desc_read(desc, sw_token);
708 buff_dma = desc_read(desc, sw_buffer);
709 origlen = desc_read(desc, sw_len);
710
711 dma_unmap_single(ctlr->dev, buff_dma, origlen, chan->dir);
712 cpdma_desc_free(pool, desc, 1);
713 (*chan->handler)(token, outlen, status);
714 }
715
__cpdma_chan_process(struct cpdma_chan * chan)716 static int __cpdma_chan_process(struct cpdma_chan *chan)
717 {
718 struct cpdma_ctlr *ctlr = chan->ctlr;
719 struct cpdma_desc __iomem *desc;
720 int status, outlen;
721 struct cpdma_desc_pool *pool = ctlr->pool;
722 dma_addr_t desc_dma;
723 unsigned long flags;
724
725 spin_lock_irqsave(&chan->lock, flags);
726
727 desc = chan->head;
728 if (!desc) {
729 chan->stats.empty_dequeue++;
730 status = -ENOENT;
731 goto unlock_ret;
732 }
733 desc_dma = desc_phys(pool, desc);
734
735 status = __raw_readl(&desc->hw_mode);
736 outlen = status & 0x7ff;
737 if (status & CPDMA_DESC_OWNER) {
738 chan->stats.busy_dequeue++;
739 status = -EBUSY;
740 goto unlock_ret;
741 }
742 status = status & (CPDMA_DESC_EOQ | CPDMA_DESC_TD_COMPLETE);
743
744 chan->head = desc_from_phys(pool, desc_read(desc, hw_next));
745 chan_write(chan, cp, desc_dma);
746 chan->count--;
747 chan->stats.good_dequeue++;
748
749 if (status & CPDMA_DESC_EOQ) {
750 chan->stats.requeue++;
751 chan_write(chan, hdp, desc_phys(pool, chan->head));
752 }
753
754 spin_unlock_irqrestore(&chan->lock, flags);
755
756 __cpdma_chan_free(chan, desc, outlen, status);
757 return status;
758
759 unlock_ret:
760 spin_unlock_irqrestore(&chan->lock, flags);
761 return status;
762 }
763
cpdma_chan_process(struct cpdma_chan * chan,int quota)764 int cpdma_chan_process(struct cpdma_chan *chan, int quota)
765 {
766 int used = 0, ret = 0;
767
768 if (chan->state != CPDMA_STATE_ACTIVE)
769 return -EINVAL;
770
771 while (used < quota) {
772 ret = __cpdma_chan_process(chan);
773 if (ret < 0)
774 break;
775 used++;
776 }
777 return used;
778 }
779
cpdma_chan_start(struct cpdma_chan * chan)780 int cpdma_chan_start(struct cpdma_chan *chan)
781 {
782 struct cpdma_ctlr *ctlr = chan->ctlr;
783 struct cpdma_desc_pool *pool = ctlr->pool;
784 unsigned long flags;
785
786 spin_lock_irqsave(&chan->lock, flags);
787 if (chan->state != CPDMA_STATE_IDLE) {
788 spin_unlock_irqrestore(&chan->lock, flags);
789 return -EBUSY;
790 }
791 if (ctlr->state != CPDMA_STATE_ACTIVE) {
792 spin_unlock_irqrestore(&chan->lock, flags);
793 return -EINVAL;
794 }
795 dma_reg_write(ctlr, chan->int_set, chan->mask);
796 chan->state = CPDMA_STATE_ACTIVE;
797 if (chan->head) {
798 chan_write(chan, hdp, desc_phys(pool, chan->head));
799 if (chan->rxfree)
800 chan_write(chan, rxfree, chan->count);
801 }
802
803 spin_unlock_irqrestore(&chan->lock, flags);
804 return 0;
805 }
806
cpdma_chan_stop(struct cpdma_chan * chan)807 int cpdma_chan_stop(struct cpdma_chan *chan)
808 {
809 struct cpdma_ctlr *ctlr = chan->ctlr;
810 struct cpdma_desc_pool *pool = ctlr->pool;
811 unsigned long flags;
812 int ret;
813 unsigned long timeout;
814
815 spin_lock_irqsave(&chan->lock, flags);
816 if (chan->state != CPDMA_STATE_ACTIVE) {
817 spin_unlock_irqrestore(&chan->lock, flags);
818 return -EINVAL;
819 }
820
821 chan->state = CPDMA_STATE_TEARDOWN;
822 dma_reg_write(ctlr, chan->int_clear, chan->mask);
823
824 /* trigger teardown */
825 dma_reg_write(ctlr, chan->td, chan_linear(chan));
826
827 /* wait for teardown complete */
828 timeout = jiffies + HZ/10; /* 100 msec */
829 while (time_before(jiffies, timeout)) {
830 u32 cp = chan_read(chan, cp);
831 if ((cp & CPDMA_TEARDOWN_VALUE) == CPDMA_TEARDOWN_VALUE)
832 break;
833 cpu_relax();
834 }
835 WARN_ON(!time_before(jiffies, timeout));
836 chan_write(chan, cp, CPDMA_TEARDOWN_VALUE);
837
838 /* handle completed packets */
839 spin_unlock_irqrestore(&chan->lock, flags);
840 do {
841 ret = __cpdma_chan_process(chan);
842 if (ret < 0)
843 break;
844 } while ((ret & CPDMA_DESC_TD_COMPLETE) == 0);
845 spin_lock_irqsave(&chan->lock, flags);
846
847 /* remaining packets haven't been tx/rx'ed, clean them up */
848 while (chan->head) {
849 struct cpdma_desc __iomem *desc = chan->head;
850 dma_addr_t next_dma;
851
852 next_dma = desc_read(desc, hw_next);
853 chan->head = desc_from_phys(pool, next_dma);
854 chan->count--;
855 chan->stats.teardown_dequeue++;
856
857 /* issue callback without locks held */
858 spin_unlock_irqrestore(&chan->lock, flags);
859 __cpdma_chan_free(chan, desc, 0, -ENOSYS);
860 spin_lock_irqsave(&chan->lock, flags);
861 }
862
863 chan->state = CPDMA_STATE_IDLE;
864 spin_unlock_irqrestore(&chan->lock, flags);
865 return 0;
866 }
867
cpdma_chan_int_ctrl(struct cpdma_chan * chan,bool enable)868 int cpdma_chan_int_ctrl(struct cpdma_chan *chan, bool enable)
869 {
870 unsigned long flags;
871
872 spin_lock_irqsave(&chan->lock, flags);
873 if (chan->state != CPDMA_STATE_ACTIVE) {
874 spin_unlock_irqrestore(&chan->lock, flags);
875 return -EINVAL;
876 }
877
878 dma_reg_write(chan->ctlr, enable ? chan->int_set : chan->int_clear,
879 chan->mask);
880 spin_unlock_irqrestore(&chan->lock, flags);
881
882 return 0;
883 }
884
885 struct cpdma_control_info {
886 u32 reg;
887 u32 shift, mask;
888 int access;
889 #define ACCESS_RO BIT(0)
890 #define ACCESS_WO BIT(1)
891 #define ACCESS_RW (ACCESS_RO | ACCESS_WO)
892 };
893
894 struct cpdma_control_info controls[] = {
895 [CPDMA_CMD_IDLE] = {CPDMA_DMACONTROL, 3, 1, ACCESS_WO},
896 [CPDMA_COPY_ERROR_FRAMES] = {CPDMA_DMACONTROL, 4, 1, ACCESS_RW},
897 [CPDMA_RX_OFF_LEN_UPDATE] = {CPDMA_DMACONTROL, 2, 1, ACCESS_RW},
898 [CPDMA_RX_OWNERSHIP_FLIP] = {CPDMA_DMACONTROL, 1, 1, ACCESS_RW},
899 [CPDMA_TX_PRIO_FIXED] = {CPDMA_DMACONTROL, 0, 1, ACCESS_RW},
900 [CPDMA_STAT_IDLE] = {CPDMA_DMASTATUS, 31, 1, ACCESS_RO},
901 [CPDMA_STAT_TX_ERR_CODE] = {CPDMA_DMASTATUS, 20, 0xf, ACCESS_RW},
902 [CPDMA_STAT_TX_ERR_CHAN] = {CPDMA_DMASTATUS, 16, 0x7, ACCESS_RW},
903 [CPDMA_STAT_RX_ERR_CODE] = {CPDMA_DMASTATUS, 12, 0xf, ACCESS_RW},
904 [CPDMA_STAT_RX_ERR_CHAN] = {CPDMA_DMASTATUS, 8, 0x7, ACCESS_RW},
905 [CPDMA_RX_BUFFER_OFFSET] = {CPDMA_RXBUFFOFS, 0, 0xffff, ACCESS_RW},
906 };
907
cpdma_control_get(struct cpdma_ctlr * ctlr,int control)908 int cpdma_control_get(struct cpdma_ctlr *ctlr, int control)
909 {
910 unsigned long flags;
911 struct cpdma_control_info *info = &controls[control];
912 int ret;
913
914 spin_lock_irqsave(&ctlr->lock, flags);
915
916 ret = -ENOTSUPP;
917 if (!ctlr->params.has_ext_regs)
918 goto unlock_ret;
919
920 ret = -EINVAL;
921 if (ctlr->state != CPDMA_STATE_ACTIVE)
922 goto unlock_ret;
923
924 ret = -ENOENT;
925 if (control < 0 || control >= ARRAY_SIZE(controls))
926 goto unlock_ret;
927
928 ret = -EPERM;
929 if ((info->access & ACCESS_RO) != ACCESS_RO)
930 goto unlock_ret;
931
932 ret = (dma_reg_read(ctlr, info->reg) >> info->shift) & info->mask;
933
934 unlock_ret:
935 spin_unlock_irqrestore(&ctlr->lock, flags);
936 return ret;
937 }
938
cpdma_control_set(struct cpdma_ctlr * ctlr,int control,int value)939 int cpdma_control_set(struct cpdma_ctlr *ctlr, int control, int value)
940 {
941 unsigned long flags;
942 struct cpdma_control_info *info = &controls[control];
943 int ret;
944 u32 val;
945
946 spin_lock_irqsave(&ctlr->lock, flags);
947
948 ret = -ENOTSUPP;
949 if (!ctlr->params.has_ext_regs)
950 goto unlock_ret;
951
952 ret = -EINVAL;
953 if (ctlr->state != CPDMA_STATE_ACTIVE)
954 goto unlock_ret;
955
956 ret = -ENOENT;
957 if (control < 0 || control >= ARRAY_SIZE(controls))
958 goto unlock_ret;
959
960 ret = -EPERM;
961 if ((info->access & ACCESS_WO) != ACCESS_WO)
962 goto unlock_ret;
963
964 val = dma_reg_read(ctlr, info->reg);
965 val &= ~(info->mask << info->shift);
966 val |= (value & info->mask) << info->shift;
967 dma_reg_write(ctlr, info->reg, val);
968 ret = 0;
969
970 unlock_ret:
971 spin_unlock_irqrestore(&ctlr->lock, flags);
972 return ret;
973 }
974