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Merge tag 'staging-3.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh...
[linux-2.6.git] / drivers / dma / mxs-dma.c
blob719593002ab7866051aa9cf7c52633ce60000ba6
1 /*
2 * Copyright 2011 Freescale Semiconductor, Inc. All Rights Reserved.
3 *
4 * Refer to drivers/dma/imx-sdma.c
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11 #include <linux/init.h>
12 #include <linux/types.h>
13 #include <linux/mm.h>
14 #include <linux/interrupt.h>
15 #include <linux/clk.h>
16 #include <linux/wait.h>
17 #include <linux/sched.h>
18 #include <linux/semaphore.h>
19 #include <linux/device.h>
20 #include <linux/dma-mapping.h>
21 #include <linux/slab.h>
22 #include <linux/platform_device.h>
23 #include <linux/dmaengine.h>
24 #include <linux/delay.h>
25 #include <linux/module.h>
26 #include <linux/fsl/mxs-dma.h>
27 #include <linux/stmp_device.h>
28 #include <linux/of.h>
29 #include <linux/of_device.h>
30 #include <linux/of_dma.h>
31
32 #include <asm/irq.h>
33
34 #include "dmaengine.h"
35
36 /*
37 * NOTE: The term "PIO" throughout the mxs-dma implementation means
38 * PIO mode of mxs apbh-dma and apbx-dma. With this working mode,
39 * dma can program the controller registers of peripheral devices.
40 */
41
42 #define dma_is_apbh(mxs_dma) ((mxs_dma)->type == MXS_DMA_APBH)
43 #define apbh_is_old(mxs_dma) ((mxs_dma)->dev_id == IMX23_DMA)
44
45 #define HW_APBHX_CTRL0 0x000
46 #define BM_APBH_CTRL0_APB_BURST8_EN (1 << 29)
47 #define BM_APBH_CTRL0_APB_BURST_EN (1 << 28)
48 #define BP_APBH_CTRL0_RESET_CHANNEL 16
49 #define HW_APBHX_CTRL1 0x010
50 #define HW_APBHX_CTRL2 0x020
51 #define HW_APBHX_CHANNEL_CTRL 0x030
52 #define BP_APBHX_CHANNEL_CTRL_RESET_CHANNEL 16
53 /*
54 * The offset of NXTCMDAR register is different per both dma type and version,
55 * while stride for each channel is all the same 0x70.
56 */
57 #define HW_APBHX_CHn_NXTCMDAR(d, n) \
58 (((dma_is_apbh(d) && apbh_is_old(d)) ? 0x050 : 0x110) + (n) * 0x70)
59 #define HW_APBHX_CHn_SEMA(d, n) \
60 (((dma_is_apbh(d) && apbh_is_old(d)) ? 0x080 : 0x140) + (n) * 0x70)
61
62 /*
63 * ccw bits definitions
64 *
65 * COMMAND: 0..1 (2)
66 * CHAIN: 2 (1)
67 * IRQ: 3 (1)
68 * NAND_LOCK: 4 (1) - not implemented
69 * NAND_WAIT4READY: 5 (1) - not implemented
70 * DEC_SEM: 6 (1)
71 * WAIT4END: 7 (1)
72 * HALT_ON_TERMINATE: 8 (1)
73 * TERMINATE_FLUSH: 9 (1)
74 * RESERVED: 10..11 (2)
75 * PIO_NUM: 12..15 (4)
76 */
77 #define BP_CCW_COMMAND 0
78 #define BM_CCW_COMMAND (3 << 0)
79 #define CCW_CHAIN (1 << 2)
80 #define CCW_IRQ (1 << 3)
81 #define CCW_DEC_SEM (1 << 6)
82 #define CCW_WAIT4END (1 << 7)
83 #define CCW_HALT_ON_TERM (1 << 8)
84 #define CCW_TERM_FLUSH (1 << 9)
85 #define BP_CCW_PIO_NUM 12
86 #define BM_CCW_PIO_NUM (0xf << 12)
87
88 #define BF_CCW(value, field) (((value) << BP_CCW_##field) & BM_CCW_##field)
89
90 #define MXS_DMA_CMD_NO_XFER 0
91 #define MXS_DMA_CMD_WRITE 1
92 #define MXS_DMA_CMD_READ 2
93 #define MXS_DMA_CMD_DMA_SENSE 3 /* not implemented */
94
95 struct mxs_dma_ccw {
96 u32 next;
97 u16 bits;
98 u16 xfer_bytes;
99 #define MAX_XFER_BYTES 0xff00
100 u32 bufaddr;
101 #define MXS_PIO_WORDS 16
102 u32 pio_words[MXS_PIO_WORDS];
103 };
104
105 #define CCW_BLOCK_SIZE (4 * PAGE_SIZE)
106 #define NUM_CCW (int)(CCW_BLOCK_SIZE / sizeof(struct mxs_dma_ccw))
107
108 struct mxs_dma_chan {
109 struct mxs_dma_engine *mxs_dma;
110 struct dma_chan chan;
111 struct dma_async_tx_descriptor desc;
112 struct tasklet_struct tasklet;
113 unsigned int chan_irq;
114 struct mxs_dma_ccw *ccw;
115 dma_addr_t ccw_phys;
116 int desc_count;
117 enum dma_status status;
118 unsigned int flags;
119 #define MXS_DMA_SG_LOOP (1 << 0)
120 };
121
122 #define MXS_DMA_CHANNELS 16
123 #define MXS_DMA_CHANNELS_MASK 0xffff
124
125 enum mxs_dma_devtype {
126 MXS_DMA_APBH,
127 MXS_DMA_APBX,
128 };
129
130 enum mxs_dma_id {
131 IMX23_DMA,
132 IMX28_DMA,
133 };
134
135 struct mxs_dma_engine {
136 enum mxs_dma_id dev_id;
137 enum mxs_dma_devtype type;
138 void __iomem *base;
139 struct clk *clk;
140 struct dma_device dma_device;
141 struct device_dma_parameters dma_parms;
142 struct mxs_dma_chan mxs_chans[MXS_DMA_CHANNELS];
143 struct platform_device *pdev;
144 unsigned int nr_channels;
145 };
146
147 struct mxs_dma_type {
148 enum mxs_dma_id id;
149 enum mxs_dma_devtype type;
150 };
151
152 static struct mxs_dma_type mxs_dma_types[] = {
153 {
154 .id = IMX23_DMA,
155 .type = MXS_DMA_APBH,
156 }, {
157 .id = IMX23_DMA,
158 .type = MXS_DMA_APBX,
159 }, {
160 .id = IMX28_DMA,
161 .type = MXS_DMA_APBH,
162 }, {
163 .id = IMX28_DMA,
164 .type = MXS_DMA_APBX,
165 }
166 };
167
168 static struct platform_device_id mxs_dma_ids[] = {
169 {
170 .name = "imx23-dma-apbh",
171 .driver_data = (kernel_ulong_t) &mxs_dma_types[0],
172 }, {
173 .name = "imx23-dma-apbx",
174 .driver_data = (kernel_ulong_t) &mxs_dma_types[1],
175 }, {
176 .name = "imx28-dma-apbh",
177 .driver_data = (kernel_ulong_t) &mxs_dma_types[2],
178 }, {
179 .name = "imx28-dma-apbx",
180 .driver_data = (kernel_ulong_t) &mxs_dma_types[3],
181 }, {
182 /* end of list */
183 }
184 };
185
186 static const struct of_device_id mxs_dma_dt_ids[] = {
187 { .compatible = "fsl,imx23-dma-apbh", .data = &mxs_dma_ids[0], },
188 { .compatible = "fsl,imx23-dma-apbx", .data = &mxs_dma_ids[1], },
189 { .compatible = "fsl,imx28-dma-apbh", .data = &mxs_dma_ids[2], },
190 { .compatible = "fsl,imx28-dma-apbx", .data = &mxs_dma_ids[3], },
191 { /* sentinel */ }
192 };
193 MODULE_DEVICE_TABLE(of, mxs_dma_dt_ids);
194
195 static struct mxs_dma_chan *to_mxs_dma_chan(struct dma_chan *chan)
196 {
197 return container_of(chan, struct mxs_dma_chan, chan);
198 }
199
200 int mxs_dma_is_apbh(struct dma_chan *chan)
201 {
202 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
203 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
204
205 return dma_is_apbh(mxs_dma);
206 }
207 EXPORT_SYMBOL_GPL(mxs_dma_is_apbh);
208
209 int mxs_dma_is_apbx(struct dma_chan *chan)
210 {
211 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
212 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
213
214 return !dma_is_apbh(mxs_dma);
215 }
216 EXPORT_SYMBOL_GPL(mxs_dma_is_apbx);
217
218 static void mxs_dma_reset_chan(struct mxs_dma_chan *mxs_chan)
219 {
220 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
221 int chan_id = mxs_chan->chan.chan_id;
222
223 if (dma_is_apbh(mxs_dma) && apbh_is_old(mxs_dma))
224 writel(1 << (chan_id + BP_APBH_CTRL0_RESET_CHANNEL),
225 mxs_dma->base + HW_APBHX_CTRL0 + STMP_OFFSET_REG_SET);
226 else
227 writel(1 << (chan_id + BP_APBHX_CHANNEL_CTRL_RESET_CHANNEL),
228 mxs_dma->base + HW_APBHX_CHANNEL_CTRL + STMP_OFFSET_REG_SET);
229 }
230
231 static void mxs_dma_enable_chan(struct mxs_dma_chan *mxs_chan)
232 {
233 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
234 int chan_id = mxs_chan->chan.chan_id;
235
236 /* set cmd_addr up */
237 writel(mxs_chan->ccw_phys,
238 mxs_dma->base + HW_APBHX_CHn_NXTCMDAR(mxs_dma, chan_id));
239
240 /* write 1 to SEMA to kick off the channel */
241 writel(1, mxs_dma->base + HW_APBHX_CHn_SEMA(mxs_dma, chan_id));
242 }
243
244 static void mxs_dma_disable_chan(struct mxs_dma_chan *mxs_chan)
245 {
246 mxs_chan->status = DMA_SUCCESS;
247 }
248
249 static void mxs_dma_pause_chan(struct mxs_dma_chan *mxs_chan)
250 {
251 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
252 int chan_id = mxs_chan->chan.chan_id;
253
254 /* freeze the channel */
255 if (dma_is_apbh(mxs_dma) && apbh_is_old(mxs_dma))
256 writel(1 << chan_id,
257 mxs_dma->base + HW_APBHX_CTRL0 + STMP_OFFSET_REG_SET);
258 else
259 writel(1 << chan_id,
260 mxs_dma->base + HW_APBHX_CHANNEL_CTRL + STMP_OFFSET_REG_SET);
261
262 mxs_chan->status = DMA_PAUSED;
263 }
264
265 static void mxs_dma_resume_chan(struct mxs_dma_chan *mxs_chan)
266 {
267 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
268 int chan_id = mxs_chan->chan.chan_id;
269
270 /* unfreeze the channel */
271 if (dma_is_apbh(mxs_dma) && apbh_is_old(mxs_dma))
272 writel(1 << chan_id,
273 mxs_dma->base + HW_APBHX_CTRL0 + STMP_OFFSET_REG_CLR);
274 else
275 writel(1 << chan_id,
276 mxs_dma->base + HW_APBHX_CHANNEL_CTRL + STMP_OFFSET_REG_CLR);
277
278 mxs_chan->status = DMA_IN_PROGRESS;
279 }
280
281 static dma_cookie_t mxs_dma_tx_submit(struct dma_async_tx_descriptor *tx)
282 {
283 return dma_cookie_assign(tx);
284 }
285
286 static void mxs_dma_tasklet(unsigned long data)
287 {
288 struct mxs_dma_chan *mxs_chan = (struct mxs_dma_chan *) data;
289
290 if (mxs_chan->desc.callback)
291 mxs_chan->desc.callback(mxs_chan->desc.callback_param);
292 }
293
294 static irqreturn_t mxs_dma_int_handler(int irq, void *dev_id)
295 {
296 struct mxs_dma_engine *mxs_dma = dev_id;
297 u32 stat1, stat2;
298
299 /* completion status */
300 stat1 = readl(mxs_dma->base + HW_APBHX_CTRL1);
301 stat1 &= MXS_DMA_CHANNELS_MASK;
302 writel(stat1, mxs_dma->base + HW_APBHX_CTRL1 + STMP_OFFSET_REG_CLR);
303
304 /* error status */
305 stat2 = readl(mxs_dma->base + HW_APBHX_CTRL2);
306 writel(stat2, mxs_dma->base + HW_APBHX_CTRL2 + STMP_OFFSET_REG_CLR);
307
308 /*
309 * When both completion and error of termination bits set at the
310 * same time, we do not take it as an error. IOW, it only becomes
311 * an error we need to handle here in case of either it's (1) a bus
312 * error or (2) a termination error with no completion.
313 */
314 stat2 = ((stat2 >> MXS_DMA_CHANNELS) & stat2) | /* (1) */
315 (~(stat2 >> MXS_DMA_CHANNELS) & stat2 & ~stat1); /* (2) */
316
317 /* combine error and completion status for checking */
318 stat1 = (stat2 << MXS_DMA_CHANNELS) | stat1;
319 while (stat1) {
320 int channel = fls(stat1) - 1;
321 struct mxs_dma_chan *mxs_chan =
322 &mxs_dma->mxs_chans[channel % MXS_DMA_CHANNELS];
323
324 if (channel >= MXS_DMA_CHANNELS) {
325 dev_dbg(mxs_dma->dma_device.dev,
326 "%s: error in channel %d\n", __func__,
327 channel - MXS_DMA_CHANNELS);
328 mxs_chan->status = DMA_ERROR;
329 mxs_dma_reset_chan(mxs_chan);
330 } else {
331 if (mxs_chan->flags & MXS_DMA_SG_LOOP)
332 mxs_chan->status = DMA_IN_PROGRESS;
333 else
334 mxs_chan->status = DMA_SUCCESS;
335 }
336
337 stat1 &= ~(1 << channel);
338
339 if (mxs_chan->status == DMA_SUCCESS)
340 dma_cookie_complete(&mxs_chan->desc);
341
342 /* schedule tasklet on this channel */
343 tasklet_schedule(&mxs_chan->tasklet);
344 }
345
346 return IRQ_HANDLED;
347 }
348
349 static int mxs_dma_alloc_chan_resources(struct dma_chan *chan)
350 {
351 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
352 struct mxs_dma_data *data = chan->private;
353 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
354 int ret;
355
356 if (data)
357 mxs_chan->chan_irq = data->chan_irq;
358
359 mxs_chan->ccw = dma_alloc_coherent(mxs_dma->dma_device.dev,
360 CCW_BLOCK_SIZE, &mxs_chan->ccw_phys,
361 GFP_KERNEL);
362 if (!mxs_chan->ccw) {
363 ret = -ENOMEM;
364 goto err_alloc;
365 }
366
367 memset(mxs_chan->ccw, 0, CCW_BLOCK_SIZE);
368
369 if (mxs_chan->chan_irq != NO_IRQ) {
370 ret = request_irq(mxs_chan->chan_irq, mxs_dma_int_handler,
371 0, "mxs-dma", mxs_dma);
372 if (ret)
373 goto err_irq;
374 }
375
376 ret = clk_prepare_enable(mxs_dma->clk);
377 if (ret)
378 goto err_clk;
379
380 mxs_dma_reset_chan(mxs_chan);
381
382 dma_async_tx_descriptor_init(&mxs_chan->desc, chan);
383 mxs_chan->desc.tx_submit = mxs_dma_tx_submit;
384
385 /* the descriptor is ready */
386 async_tx_ack(&mxs_chan->desc);
387
388 return 0;
389
390 err_clk:
391 free_irq(mxs_chan->chan_irq, mxs_dma);
392 err_irq:
393 dma_free_coherent(mxs_dma->dma_device.dev, CCW_BLOCK_SIZE,
394 mxs_chan->ccw, mxs_chan->ccw_phys);
395 err_alloc:
396 return ret;
397 }
398
399 static void mxs_dma_free_chan_resources(struct dma_chan *chan)
400 {
401 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
402 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
403
404 mxs_dma_disable_chan(mxs_chan);
405
406 free_irq(mxs_chan->chan_irq, mxs_dma);
407
408 dma_free_coherent(mxs_dma->dma_device.dev, CCW_BLOCK_SIZE,
409 mxs_chan->ccw, mxs_chan->ccw_phys);
410
411 clk_disable_unprepare(mxs_dma->clk);
412 }
413
414 /*
415 * How to use the flags for ->device_prep_slave_sg() :
416 * [1] If there is only one DMA command in the DMA chain, the code should be:
417 * ......
418 * ->device_prep_slave_sg(DMA_CTRL_ACK);
419 * ......
420 * [2] If there are two DMA commands in the DMA chain, the code should be
421 * ......
422 * ->device_prep_slave_sg(0);
423 * ......
424 * ->device_prep_slave_sg(DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
425 * ......
426 * [3] If there are more than two DMA commands in the DMA chain, the code
427 * should be:
428 * ......
429 * ->device_prep_slave_sg(0); // First
430 * ......
431 * ->device_prep_slave_sg(DMA_PREP_INTERRUPT [| DMA_CTRL_ACK]);
432 * ......
433 * ->device_prep_slave_sg(DMA_PREP_INTERRUPT | DMA_CTRL_ACK); // Last
434 * ......
435 */
436 static struct dma_async_tx_descriptor *mxs_dma_prep_slave_sg(
437 struct dma_chan *chan, struct scatterlist *sgl,
438 unsigned int sg_len, enum dma_transfer_direction direction,
439 unsigned long flags, void *context)
440 {
441 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
442 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
443 struct mxs_dma_ccw *ccw;
444 struct scatterlist *sg;
445 u32 i, j;
446 u32 *pio;
447 bool append = flags & DMA_PREP_INTERRUPT;
448 int idx = append ? mxs_chan->desc_count : 0;
449
450 if (mxs_chan->status == DMA_IN_PROGRESS && !append)
451 return NULL;
452
453 if (sg_len + (append ? idx : 0) > NUM_CCW) {
454 dev_err(mxs_dma->dma_device.dev,
455 "maximum number of sg exceeded: %d > %d\n",
456 sg_len, NUM_CCW);
457 goto err_out;
458 }
459
460 mxs_chan->status = DMA_IN_PROGRESS;
461 mxs_chan->flags = 0;
462
463 /*
464 * If the sg is prepared with append flag set, the sg
465 * will be appended to the last prepared sg.
466 */
467 if (append) {
468 BUG_ON(idx < 1);
469 ccw = &mxs_chan->ccw[idx - 1];
470 ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * idx;
471 ccw->bits |= CCW_CHAIN;
472 ccw->bits &= ~CCW_IRQ;
473 ccw->bits &= ~CCW_DEC_SEM;
474 } else {
475 idx = 0;
476 }
477
478 if (direction == DMA_TRANS_NONE) {
479 ccw = &mxs_chan->ccw[idx++];
480 pio = (u32 *) sgl;
481
482 for (j = 0; j < sg_len;)
483 ccw->pio_words[j++] = *pio++;
484
485 ccw->bits = 0;
486 ccw->bits |= CCW_IRQ;
487 ccw->bits |= CCW_DEC_SEM;
488 if (flags & DMA_CTRL_ACK)
489 ccw->bits |= CCW_WAIT4END;
490 ccw->bits |= CCW_HALT_ON_TERM;
491 ccw->bits |= CCW_TERM_FLUSH;
492 ccw->bits |= BF_CCW(sg_len, PIO_NUM);
493 ccw->bits |= BF_CCW(MXS_DMA_CMD_NO_XFER, COMMAND);
494 } else {
495 for_each_sg(sgl, sg, sg_len, i) {
496 if (sg_dma_len(sg) > MAX_XFER_BYTES) {
497 dev_err(mxs_dma->dma_device.dev, "maximum bytes for sg entry exceeded: %d > %d\n",
498 sg_dma_len(sg), MAX_XFER_BYTES);
499 goto err_out;
500 }
501
502 ccw = &mxs_chan->ccw[idx++];
503
504 ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * idx;
505 ccw->bufaddr = sg->dma_address;
506 ccw->xfer_bytes = sg_dma_len(sg);
507
508 ccw->bits = 0;
509 ccw->bits |= CCW_CHAIN;
510 ccw->bits |= CCW_HALT_ON_TERM;
511 ccw->bits |= CCW_TERM_FLUSH;
512 ccw->bits |= BF_CCW(direction == DMA_DEV_TO_MEM ?
513 MXS_DMA_CMD_WRITE : MXS_DMA_CMD_READ,
514 COMMAND);
515
516 if (i + 1 == sg_len) {
517 ccw->bits &= ~CCW_CHAIN;
518 ccw->bits |= CCW_IRQ;
519 ccw->bits |= CCW_DEC_SEM;
520 if (flags & DMA_CTRL_ACK)
521 ccw->bits |= CCW_WAIT4END;
522 }
523 }
524 }
525 mxs_chan->desc_count = idx;
526
527 return &mxs_chan->desc;
528
529 err_out:
530 mxs_chan->status = DMA_ERROR;
531 return NULL;
532 }
533
534 static struct dma_async_tx_descriptor *mxs_dma_prep_dma_cyclic(
535 struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
536 size_t period_len, enum dma_transfer_direction direction,
537 unsigned long flags, void *context)
538 {
539 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
540 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
541 u32 num_periods = buf_len / period_len;
542 u32 i = 0, buf = 0;
543
544 if (mxs_chan->status == DMA_IN_PROGRESS)
545 return NULL;
546
547 mxs_chan->status = DMA_IN_PROGRESS;
548 mxs_chan->flags |= MXS_DMA_SG_LOOP;
549
550 if (num_periods > NUM_CCW) {
551 dev_err(mxs_dma->dma_device.dev,
552 "maximum number of sg exceeded: %d > %d\n",
553 num_periods, NUM_CCW);
554 goto err_out;
555 }
556
557 if (period_len > MAX_XFER_BYTES) {
558 dev_err(mxs_dma->dma_device.dev,
559 "maximum period size exceeded: %d > %d\n",
560 period_len, MAX_XFER_BYTES);
561 goto err_out;
562 }
563
564 while (buf < buf_len) {
565 struct mxs_dma_ccw *ccw = &mxs_chan->ccw[i];
566
567 if (i + 1 == num_periods)
568 ccw->next = mxs_chan->ccw_phys;
569 else
570 ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * (i + 1);
571
572 ccw->bufaddr = dma_addr;
573 ccw->xfer_bytes = period_len;
574
575 ccw->bits = 0;
576 ccw->bits |= CCW_CHAIN;
577 ccw->bits |= CCW_IRQ;
578 ccw->bits |= CCW_HALT_ON_TERM;
579 ccw->bits |= CCW_TERM_FLUSH;
580 ccw->bits |= BF_CCW(direction == DMA_DEV_TO_MEM ?
581 MXS_DMA_CMD_WRITE : MXS_DMA_CMD_READ, COMMAND);
582
583 dma_addr += period_len;
584 buf += period_len;
585
586 i++;
587 }
588 mxs_chan->desc_count = i;
589
590 return &mxs_chan->desc;
591
592 err_out:
593 mxs_chan->status = DMA_ERROR;
594 return NULL;
595 }
596
597 static int mxs_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
598 unsigned long arg)
599 {
600 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
601 int ret = 0;
602
603 switch (cmd) {
604 case DMA_TERMINATE_ALL:
605 mxs_dma_reset_chan(mxs_chan);
606 mxs_dma_disable_chan(mxs_chan);
607 break;
608 case DMA_PAUSE:
609 mxs_dma_pause_chan(mxs_chan);
610 break;
611 case DMA_RESUME:
612 mxs_dma_resume_chan(mxs_chan);
613 break;
614 default:
615 ret = -ENOSYS;
616 }
617
618 return ret;
619 }
620
621 static enum dma_status mxs_dma_tx_status(struct dma_chan *chan,
622 dma_cookie_t cookie, struct dma_tx_state *txstate)
623 {
624 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
625 dma_cookie_t last_used;
626
627 last_used = chan->cookie;
628 dma_set_tx_state(txstate, chan->completed_cookie, last_used, 0);
629
630 return mxs_chan->status;
631 }
632
633 static void mxs_dma_issue_pending(struct dma_chan *chan)
634 {
635 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
636
637 mxs_dma_enable_chan(mxs_chan);
638 }
639
640 static int __init mxs_dma_init(struct mxs_dma_engine *mxs_dma)
641 {
642 int ret;
643
644 ret = clk_prepare_enable(mxs_dma->clk);
645 if (ret)
646 return ret;
647
648 ret = stmp_reset_block(mxs_dma->base);
649 if (ret)
650 goto err_out;
651
652 /* enable apbh burst */
653 if (dma_is_apbh(mxs_dma)) {
654 writel(BM_APBH_CTRL0_APB_BURST_EN,
655 mxs_dma->base + HW_APBHX_CTRL0 + STMP_OFFSET_REG_SET);
656 writel(BM_APBH_CTRL0_APB_BURST8_EN,
657 mxs_dma->base + HW_APBHX_CTRL0 + STMP_OFFSET_REG_SET);
658 }
659
660 /* enable irq for all the channels */
661 writel(MXS_DMA_CHANNELS_MASK << MXS_DMA_CHANNELS,
662 mxs_dma->base + HW_APBHX_CTRL1 + STMP_OFFSET_REG_SET);
663
664 err_out:
665 clk_disable_unprepare(mxs_dma->clk);
666 return ret;
667 }
668
669 struct mxs_dma_filter_param {
670 struct device_node *of_node;
671 unsigned int chan_id;
672 };
673
674 static bool mxs_dma_filter_fn(struct dma_chan *chan, void *fn_param)
675 {
676 struct mxs_dma_filter_param *param = fn_param;
677 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
678 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
679 int chan_irq;
680
681 if (mxs_dma->dma_device.dev->of_node != param->of_node)
682 return false;
683
684 if (chan->chan_id != param->chan_id)
685 return false;
686
687 chan_irq = platform_get_irq(mxs_dma->pdev, param->chan_id);
688 if (chan_irq < 0)
689 return false;
690
691 mxs_chan->chan_irq = chan_irq;
692
693 return true;
694 }
695
696 static struct dma_chan *mxs_dma_xlate(struct of_phandle_args *dma_spec,
697 struct of_dma *ofdma)
698 {
699 struct mxs_dma_engine *mxs_dma = ofdma->of_dma_data;
700 dma_cap_mask_t mask = mxs_dma->dma_device.cap_mask;
701 struct mxs_dma_filter_param param;
702
703 if (dma_spec->args_count != 1)
704 return NULL;
705
706 param.of_node = ofdma->of_node;
707 param.chan_id = dma_spec->args[0];
708
709 if (param.chan_id >= mxs_dma->nr_channels)
710 return NULL;
711
712 return dma_request_channel(mask, mxs_dma_filter_fn, &param);
713 }
714
715 static int __init mxs_dma_probe(struct platform_device *pdev)
716 {
717 struct device_node *np = pdev->dev.of_node;
718 const struct platform_device_id *id_entry;
719 const struct of_device_id *of_id;
720 const struct mxs_dma_type *dma_type;
721 struct mxs_dma_engine *mxs_dma;
722 struct resource *iores;
723 int ret, i;
724
725 mxs_dma = devm_kzalloc(&pdev->dev, sizeof(*mxs_dma), GFP_KERNEL);
726 if (!mxs_dma)
727 return -ENOMEM;
728
729 ret = of_property_read_u32(np, "dma-channels", &mxs_dma->nr_channels);
730 if (ret) {
731 dev_err(&pdev->dev, "failed to read dma-channels\n");
732 return ret;
733 }
734
735 of_id = of_match_device(mxs_dma_dt_ids, &pdev->dev);
736 if (of_id)
737 id_entry = of_id->data;
738 else
739 id_entry = platform_get_device_id(pdev);
740
741 dma_type = (struct mxs_dma_type *)id_entry->driver_data;
742 mxs_dma->type = dma_type->type;
743 mxs_dma->dev_id = dma_type->id;
744
745 iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
746 mxs_dma->base = devm_ioremap_resource(&pdev->dev, iores);
747 if (IS_ERR(mxs_dma->base))
748 return PTR_ERR(mxs_dma->base);
749
750 mxs_dma->clk = devm_clk_get(&pdev->dev, NULL);
751 if (IS_ERR(mxs_dma->clk))
752 return PTR_ERR(mxs_dma->clk);
753
754 dma_cap_set(DMA_SLAVE, mxs_dma->dma_device.cap_mask);
755 dma_cap_set(DMA_CYCLIC, mxs_dma->dma_device.cap_mask);
756
757 INIT_LIST_HEAD(&mxs_dma->dma_device.channels);
758
759 /* Initialize channel parameters */
760 for (i = 0; i < MXS_DMA_CHANNELS; i++) {
761 struct mxs_dma_chan *mxs_chan = &mxs_dma->mxs_chans[i];
762
763 mxs_chan->mxs_dma = mxs_dma;
764 mxs_chan->chan.device = &mxs_dma->dma_device;
765 dma_cookie_init(&mxs_chan->chan);
766
767 tasklet_init(&mxs_chan->tasklet, mxs_dma_tasklet,
768 (unsigned long) mxs_chan);
769
770
771 /* Add the channel to mxs_chan list */
772 list_add_tail(&mxs_chan->chan.device_node,
773 &mxs_dma->dma_device.channels);
774 }
775
776 ret = mxs_dma_init(mxs_dma);
777 if (ret)
778 return ret;
779
780 mxs_dma->pdev = pdev;
781 mxs_dma->dma_device.dev = &pdev->dev;
782
783 /* mxs_dma gets 65535 bytes maximum sg size */
784 mxs_dma->dma_device.dev->dma_parms = &mxs_dma->dma_parms;
785 dma_set_max_seg_size(mxs_dma->dma_device.dev, MAX_XFER_BYTES);
786
787 mxs_dma->dma_device.device_alloc_chan_resources = mxs_dma_alloc_chan_resources;
788 mxs_dma->dma_device.device_free_chan_resources = mxs_dma_free_chan_resources;
789 mxs_dma->dma_device.device_tx_status = mxs_dma_tx_status;
790 mxs_dma->dma_device.device_prep_slave_sg = mxs_dma_prep_slave_sg;
791 mxs_dma->dma_device.device_prep_dma_cyclic = mxs_dma_prep_dma_cyclic;
792 mxs_dma->dma_device.device_control = mxs_dma_control;
793 mxs_dma->dma_device.device_issue_pending = mxs_dma_issue_pending;
794
795 ret = dma_async_device_register(&mxs_dma->dma_device);
796 if (ret) {
797 dev_err(mxs_dma->dma_device.dev, "unable to register\n");
798 return ret;
799 }
800
801 ret = of_dma_controller_register(np, mxs_dma_xlate, mxs_dma);
802 if (ret) {
803 dev_err(mxs_dma->dma_device.dev,
804 "failed to register controller\n");
805 dma_async_device_unregister(&mxs_dma->dma_device);
806 }
807
808 dev_info(mxs_dma->dma_device.dev, "initialized\n");
809
810 return 0;
811 }
812
813 static struct platform_driver mxs_dma_driver = {
814 .driver = {
815 .name = "mxs-dma",
816 .of_match_table = mxs_dma_dt_ids,
817 },
818 .id_table = mxs_dma_ids,
819 };
820
821 static int __init mxs_dma_module_init(void)
822 {
823 return platform_driver_probe(&mxs_dma_driver, mxs_dma_probe);
824 }
825 subsys_initcall(mxs_dma_module_init);
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