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proc: use "unsigned int" for sigqueue length
[linux/fpc-iii.git] / drivers / dma / tegra20-apb-dma.c
blob9a558e30c461c4f5b9d26ecf4b8602e05a3a2e85
1 /*
2 * DMA driver for Nvidia's Tegra20 APB DMA controller.
3 *
4 * Copyright (c) 2012-2013, NVIDIA CORPORATION. All rights reserved.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
17 */
18
19 #include <linux/bitops.h>
20 #include <linux/clk.h>
21 #include <linux/delay.h>
22 #include <linux/dmaengine.h>
23 #include <linux/dma-mapping.h>
24 #include <linux/err.h>
25 #include <linux/init.h>
26 #include <linux/interrupt.h>
27 #include <linux/io.h>
28 #include <linux/mm.h>
29 #include <linux/module.h>
30 #include <linux/of.h>
31 #include <linux/of_device.h>
32 #include <linux/of_dma.h>
33 #include <linux/platform_device.h>
34 #include <linux/pm.h>
35 #include <linux/pm_runtime.h>
36 #include <linux/reset.h>
37 #include <linux/slab.h>
38
39 #include "dmaengine.h"
40
41 #define TEGRA_APBDMA_GENERAL 0x0
42 #define TEGRA_APBDMA_GENERAL_ENABLE BIT(31)
43
44 #define TEGRA_APBDMA_CONTROL 0x010
45 #define TEGRA_APBDMA_IRQ_MASK 0x01c
46 #define TEGRA_APBDMA_IRQ_MASK_SET 0x020
47
48 /* CSR register */
49 #define TEGRA_APBDMA_CHAN_CSR 0x00
50 #define TEGRA_APBDMA_CSR_ENB BIT(31)
51 #define TEGRA_APBDMA_CSR_IE_EOC BIT(30)
52 #define TEGRA_APBDMA_CSR_HOLD BIT(29)
53 #define TEGRA_APBDMA_CSR_DIR BIT(28)
54 #define TEGRA_APBDMA_CSR_ONCE BIT(27)
55 #define TEGRA_APBDMA_CSR_FLOW BIT(21)
56 #define TEGRA_APBDMA_CSR_REQ_SEL_SHIFT 16
57 #define TEGRA_APBDMA_CSR_REQ_SEL_MASK 0x1F
58 #define TEGRA_APBDMA_CSR_WCOUNT_MASK 0xFFFC
59
60 /* STATUS register */
61 #define TEGRA_APBDMA_CHAN_STATUS 0x004
62 #define TEGRA_APBDMA_STATUS_BUSY BIT(31)
63 #define TEGRA_APBDMA_STATUS_ISE_EOC BIT(30)
64 #define TEGRA_APBDMA_STATUS_HALT BIT(29)
65 #define TEGRA_APBDMA_STATUS_PING_PONG BIT(28)
66 #define TEGRA_APBDMA_STATUS_COUNT_SHIFT 2
67 #define TEGRA_APBDMA_STATUS_COUNT_MASK 0xFFFC
68
69 #define TEGRA_APBDMA_CHAN_CSRE 0x00C
70 #define TEGRA_APBDMA_CHAN_CSRE_PAUSE (1 << 31)
71
72 /* AHB memory address */
73 #define TEGRA_APBDMA_CHAN_AHBPTR 0x010
74
75 /* AHB sequence register */
76 #define TEGRA_APBDMA_CHAN_AHBSEQ 0x14
77 #define TEGRA_APBDMA_AHBSEQ_INTR_ENB BIT(31)
78 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_8 (0 << 28)
79 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_16 (1 << 28)
80 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32 (2 << 28)
81 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_64 (3 << 28)
82 #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_128 (4 << 28)
83 #define TEGRA_APBDMA_AHBSEQ_DATA_SWAP BIT(27)
84 #define TEGRA_APBDMA_AHBSEQ_BURST_1 (4 << 24)
85 #define TEGRA_APBDMA_AHBSEQ_BURST_4 (5 << 24)
86 #define TEGRA_APBDMA_AHBSEQ_BURST_8 (6 << 24)
87 #define TEGRA_APBDMA_AHBSEQ_DBL_BUF BIT(19)
88 #define TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT 16
89 #define TEGRA_APBDMA_AHBSEQ_WRAP_NONE 0
90
91 /* APB address */
92 #define TEGRA_APBDMA_CHAN_APBPTR 0x018
93
94 /* APB sequence register */
95 #define TEGRA_APBDMA_CHAN_APBSEQ 0x01c
96 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8 (0 << 28)
97 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16 (1 << 28)
98 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32 (2 << 28)
99 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64 (3 << 28)
100 #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_128 (4 << 28)
101 #define TEGRA_APBDMA_APBSEQ_DATA_SWAP BIT(27)
102 #define TEGRA_APBDMA_APBSEQ_WRAP_WORD_1 (1 << 16)
103
104 /* Tegra148 specific registers */
105 #define TEGRA_APBDMA_CHAN_WCOUNT 0x20
106
107 #define TEGRA_APBDMA_CHAN_WORD_TRANSFER 0x24
108
109 /*
110 * If any burst is in flight and DMA paused then this is the time to complete
111 * on-flight burst and update DMA status register.
112 */
113 #define TEGRA_APBDMA_BURST_COMPLETE_TIME 20
114
115 /* Channel base address offset from APBDMA base address */
116 #define TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET 0x1000
117
118 #define TEGRA_APBDMA_SLAVE_ID_INVALID (TEGRA_APBDMA_CSR_REQ_SEL_MASK + 1)
119
120 struct tegra_dma;
121
122 /*
123 * tegra_dma_chip_data Tegra chip specific DMA data
124 * @nr_channels: Number of channels available in the controller.
125 * @channel_reg_size: Channel register size/stride.
126 * @max_dma_count: Maximum DMA transfer count supported by DMA controller.
127 * @support_channel_pause: Support channel wise pause of dma.
128 * @support_separate_wcount_reg: Support separate word count register.
129 */
130 struct tegra_dma_chip_data {
131 int nr_channels;
132 int channel_reg_size;
133 int max_dma_count;
134 bool support_channel_pause;
135 bool support_separate_wcount_reg;
136 };
137
138 /* DMA channel registers */
139 struct tegra_dma_channel_regs {
140 unsigned long csr;
141 unsigned long ahb_ptr;
142 unsigned long apb_ptr;
143 unsigned long ahb_seq;
144 unsigned long apb_seq;
145 unsigned long wcount;
146 };
147
148 /*
149 * tegra_dma_sg_req: Dma request details to configure hardware. This
150 * contains the details for one transfer to configure DMA hw.
151 * The client's request for data transfer can be broken into multiple
152 * sub-transfer as per requester details and hw support.
153 * This sub transfer get added in the list of transfer and point to Tegra
154 * DMA descriptor which manages the transfer details.
155 */
156 struct tegra_dma_sg_req {
157 struct tegra_dma_channel_regs ch_regs;
158 int req_len;
159 bool configured;
160 bool last_sg;
161 struct list_head node;
162 struct tegra_dma_desc *dma_desc;
163 };
164
165 /*
166 * tegra_dma_desc: Tegra DMA descriptors which manages the client requests.
167 * This descriptor keep track of transfer status, callbacks and request
168 * counts etc.
169 */
170 struct tegra_dma_desc {
171 struct dma_async_tx_descriptor txd;
172 int bytes_requested;
173 int bytes_transferred;
174 enum dma_status dma_status;
175 struct list_head node;
176 struct list_head tx_list;
177 struct list_head cb_node;
178 int cb_count;
179 };
180
181 struct tegra_dma_channel;
182
183 typedef void (*dma_isr_handler)(struct tegra_dma_channel *tdc,
184 bool to_terminate);
185
186 /* tegra_dma_channel: Channel specific information */
187 struct tegra_dma_channel {
188 struct dma_chan dma_chan;
189 char name[30];
190 bool config_init;
191 int id;
192 int irq;
193 void __iomem *chan_addr;
194 spinlock_t lock;
195 bool busy;
196 struct tegra_dma *tdma;
197 bool cyclic;
198
199 /* Different lists for managing the requests */
200 struct list_head free_sg_req;
201 struct list_head pending_sg_req;
202 struct list_head free_dma_desc;
203 struct list_head cb_desc;
204
205 /* ISR handler and tasklet for bottom half of isr handling */
206 dma_isr_handler isr_handler;
207 struct tasklet_struct tasklet;
208
209 /* Channel-slave specific configuration */
210 unsigned int slave_id;
211 struct dma_slave_config dma_sconfig;
212 struct tegra_dma_channel_regs channel_reg;
213 };
214
215 /* tegra_dma: Tegra DMA specific information */
216 struct tegra_dma {
217 struct dma_device dma_dev;
218 struct device *dev;
219 struct clk *dma_clk;
220 struct reset_control *rst;
221 spinlock_t global_lock;
222 void __iomem *base_addr;
223 const struct tegra_dma_chip_data *chip_data;
224
225 /*
226 * Counter for managing global pausing of the DMA controller.
227 * Only applicable for devices that don't support individual
228 * channel pausing.
229 */
230 u32 global_pause_count;
231
232 /* Some register need to be cache before suspend */
233 u32 reg_gen;
234
235 /* Last member of the structure */
236 struct tegra_dma_channel channels[0];
237 };
238
239 static inline void tdma_write(struct tegra_dma *tdma, u32 reg, u32 val)
240 {
241 writel(val, tdma->base_addr + reg);
242 }
243
244 static inline u32 tdma_read(struct tegra_dma *tdma, u32 reg)
245 {
246 return readl(tdma->base_addr + reg);
247 }
248
249 static inline void tdc_write(struct tegra_dma_channel *tdc,
250 u32 reg, u32 val)
251 {
252 writel(val, tdc->chan_addr + reg);
253 }
254
255 static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg)
256 {
257 return readl(tdc->chan_addr + reg);
258 }
259
260 static inline struct tegra_dma_channel *to_tegra_dma_chan(struct dma_chan *dc)
261 {
262 return container_of(dc, struct tegra_dma_channel, dma_chan);
263 }
264
265 static inline struct tegra_dma_desc *txd_to_tegra_dma_desc(
266 struct dma_async_tx_descriptor *td)
267 {
268 return container_of(td, struct tegra_dma_desc, txd);
269 }
270
271 static inline struct device *tdc2dev(struct tegra_dma_channel *tdc)
272 {
273 return &tdc->dma_chan.dev->device;
274 }
275
276 static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *tx);
277 static int tegra_dma_runtime_suspend(struct device *dev);
278 static int tegra_dma_runtime_resume(struct device *dev);
279
280 /* Get DMA desc from free list, if not there then allocate it. */
281 static struct tegra_dma_desc *tegra_dma_desc_get(
282 struct tegra_dma_channel *tdc)
283 {
284 struct tegra_dma_desc *dma_desc;
285 unsigned long flags;
286
287 spin_lock_irqsave(&tdc->lock, flags);
288
289 /* Do not allocate if desc are waiting for ack */
290 list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
291 if (async_tx_test_ack(&dma_desc->txd)) {
292 list_del(&dma_desc->node);
293 spin_unlock_irqrestore(&tdc->lock, flags);
294 dma_desc->txd.flags = 0;
295 return dma_desc;
296 }
297 }
298
299 spin_unlock_irqrestore(&tdc->lock, flags);
300
301 /* Allocate DMA desc */
302 dma_desc = kzalloc(sizeof(*dma_desc), GFP_NOWAIT);
303 if (!dma_desc)
304 return NULL;
305
306 dma_async_tx_descriptor_init(&dma_desc->txd, &tdc->dma_chan);
307 dma_desc->txd.tx_submit = tegra_dma_tx_submit;
308 dma_desc->txd.flags = 0;
309 return dma_desc;
310 }
311
312 static void tegra_dma_desc_put(struct tegra_dma_channel *tdc,
313 struct tegra_dma_desc *dma_desc)
314 {
315 unsigned long flags;
316
317 spin_lock_irqsave(&tdc->lock, flags);
318 if (!list_empty(&dma_desc->tx_list))
319 list_splice_init(&dma_desc->tx_list, &tdc->free_sg_req);
320 list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
321 spin_unlock_irqrestore(&tdc->lock, flags);
322 }
323
324 static struct tegra_dma_sg_req *tegra_dma_sg_req_get(
325 struct tegra_dma_channel *tdc)
326 {
327 struct tegra_dma_sg_req *sg_req = NULL;
328 unsigned long flags;
329
330 spin_lock_irqsave(&tdc->lock, flags);
331 if (!list_empty(&tdc->free_sg_req)) {
332 sg_req = list_first_entry(&tdc->free_sg_req,
333 typeof(*sg_req), node);
334 list_del(&sg_req->node);
335 spin_unlock_irqrestore(&tdc->lock, flags);
336 return sg_req;
337 }
338 spin_unlock_irqrestore(&tdc->lock, flags);
339
340 sg_req = kzalloc(sizeof(struct tegra_dma_sg_req), GFP_NOWAIT);
341
342 return sg_req;
343 }
344
345 static int tegra_dma_slave_config(struct dma_chan *dc,
346 struct dma_slave_config *sconfig)
347 {
348 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
349
350 if (!list_empty(&tdc->pending_sg_req)) {
351 dev_err(tdc2dev(tdc), "Configuration not allowed\n");
352 return -EBUSY;
353 }
354
355 memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig));
356 if (tdc->slave_id == TEGRA_APBDMA_SLAVE_ID_INVALID &&
357 sconfig->device_fc) {
358 if (sconfig->slave_id > TEGRA_APBDMA_CSR_REQ_SEL_MASK)
359 return -EINVAL;
360 tdc->slave_id = sconfig->slave_id;
361 }
362 tdc->config_init = true;
363 return 0;
364 }
365
366 static void tegra_dma_global_pause(struct tegra_dma_channel *tdc,
367 bool wait_for_burst_complete)
368 {
369 struct tegra_dma *tdma = tdc->tdma;
370
371 spin_lock(&tdma->global_lock);
372
373 if (tdc->tdma->global_pause_count == 0) {
374 tdma_write(tdma, TEGRA_APBDMA_GENERAL, 0);
375 if (wait_for_burst_complete)
376 udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
377 }
378
379 tdc->tdma->global_pause_count++;
380
381 spin_unlock(&tdma->global_lock);
382 }
383
384 static void tegra_dma_global_resume(struct tegra_dma_channel *tdc)
385 {
386 struct tegra_dma *tdma = tdc->tdma;
387
388 spin_lock(&tdma->global_lock);
389
390 if (WARN_ON(tdc->tdma->global_pause_count == 0))
391 goto out;
392
393 if (--tdc->tdma->global_pause_count == 0)
394 tdma_write(tdma, TEGRA_APBDMA_GENERAL,
395 TEGRA_APBDMA_GENERAL_ENABLE);
396
397 out:
398 spin_unlock(&tdma->global_lock);
399 }
400
401 static void tegra_dma_pause(struct tegra_dma_channel *tdc,
402 bool wait_for_burst_complete)
403 {
404 struct tegra_dma *tdma = tdc->tdma;
405
406 if (tdma->chip_data->support_channel_pause) {
407 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE,
408 TEGRA_APBDMA_CHAN_CSRE_PAUSE);
409 if (wait_for_burst_complete)
410 udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
411 } else {
412 tegra_dma_global_pause(tdc, wait_for_burst_complete);
413 }
414 }
415
416 static void tegra_dma_resume(struct tegra_dma_channel *tdc)
417 {
418 struct tegra_dma *tdma = tdc->tdma;
419
420 if (tdma->chip_data->support_channel_pause) {
421 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE, 0);
422 } else {
423 tegra_dma_global_resume(tdc);
424 }
425 }
426
427 static void tegra_dma_stop(struct tegra_dma_channel *tdc)
428 {
429 u32 csr;
430 u32 status;
431
432 /* Disable interrupts */
433 csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR);
434 csr &= ~TEGRA_APBDMA_CSR_IE_EOC;
435 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr);
436
437 /* Disable DMA */
438 csr &= ~TEGRA_APBDMA_CSR_ENB;
439 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr);
440
441 /* Clear interrupt status if it is there */
442 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
443 if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
444 dev_dbg(tdc2dev(tdc), "%s():clearing interrupt\n", __func__);
445 tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status);
446 }
447 tdc->busy = false;
448 }
449
450 static void tegra_dma_start(struct tegra_dma_channel *tdc,
451 struct tegra_dma_sg_req *sg_req)
452 {
453 struct tegra_dma_channel_regs *ch_regs = &sg_req->ch_regs;
454
455 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, ch_regs->csr);
456 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_regs->apb_seq);
457 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_regs->apb_ptr);
458 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_regs->ahb_seq);
459 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_regs->ahb_ptr);
460 if (tdc->tdma->chip_data->support_separate_wcount_reg)
461 tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT, ch_regs->wcount);
462
463 /* Start DMA */
464 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
465 ch_regs->csr | TEGRA_APBDMA_CSR_ENB);
466 }
467
468 static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc,
469 struct tegra_dma_sg_req *nsg_req)
470 {
471 unsigned long status;
472
473 /*
474 * The DMA controller reloads the new configuration for next transfer
475 * after last burst of current transfer completes.
476 * If there is no IEC status then this makes sure that last burst
477 * has not be completed. There may be case that last burst is on
478 * flight and so it can complete but because DMA is paused, it
479 * will not generates interrupt as well as not reload the new
480 * configuration.
481 * If there is already IEC status then interrupt handler need to
482 * load new configuration.
483 */
484 tegra_dma_pause(tdc, false);
485 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
486
487 /*
488 * If interrupt is pending then do nothing as the ISR will handle
489 * the programing for new request.
490 */
491 if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
492 dev_err(tdc2dev(tdc),
493 "Skipping new configuration as interrupt is pending\n");
494 tegra_dma_resume(tdc);
495 return;
496 }
497
498 /* Safe to program new configuration */
499 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, nsg_req->ch_regs.apb_ptr);
500 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, nsg_req->ch_regs.ahb_ptr);
501 if (tdc->tdma->chip_data->support_separate_wcount_reg)
502 tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT,
503 nsg_req->ch_regs.wcount);
504 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
505 nsg_req->ch_regs.csr | TEGRA_APBDMA_CSR_ENB);
506 nsg_req->configured = true;
507
508 tegra_dma_resume(tdc);
509 }
510
511 static void tdc_start_head_req(struct tegra_dma_channel *tdc)
512 {
513 struct tegra_dma_sg_req *sg_req;
514
515 if (list_empty(&tdc->pending_sg_req))
516 return;
517
518 sg_req = list_first_entry(&tdc->pending_sg_req,
519 typeof(*sg_req), node);
520 tegra_dma_start(tdc, sg_req);
521 sg_req->configured = true;
522 tdc->busy = true;
523 }
524
525 static void tdc_configure_next_head_desc(struct tegra_dma_channel *tdc)
526 {
527 struct tegra_dma_sg_req *hsgreq;
528 struct tegra_dma_sg_req *hnsgreq;
529
530 if (list_empty(&tdc->pending_sg_req))
531 return;
532
533 hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
534 if (!list_is_last(&hsgreq->node, &tdc->pending_sg_req)) {
535 hnsgreq = list_first_entry(&hsgreq->node,
536 typeof(*hnsgreq), node);
537 tegra_dma_configure_for_next(tdc, hnsgreq);
538 }
539 }
540
541 static inline int get_current_xferred_count(struct tegra_dma_channel *tdc,
542 struct tegra_dma_sg_req *sg_req, unsigned long status)
543 {
544 return sg_req->req_len - (status & TEGRA_APBDMA_STATUS_COUNT_MASK) - 4;
545 }
546
547 static void tegra_dma_abort_all(struct tegra_dma_channel *tdc)
548 {
549 struct tegra_dma_sg_req *sgreq;
550 struct tegra_dma_desc *dma_desc;
551
552 while (!list_empty(&tdc->pending_sg_req)) {
553 sgreq = list_first_entry(&tdc->pending_sg_req,
554 typeof(*sgreq), node);
555 list_move_tail(&sgreq->node, &tdc->free_sg_req);
556 if (sgreq->last_sg) {
557 dma_desc = sgreq->dma_desc;
558 dma_desc->dma_status = DMA_ERROR;
559 list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
560
561 /* Add in cb list if it is not there. */
562 if (!dma_desc->cb_count)
563 list_add_tail(&dma_desc->cb_node,
564 &tdc->cb_desc);
565 dma_desc->cb_count++;
566 }
567 }
568 tdc->isr_handler = NULL;
569 }
570
571 static bool handle_continuous_head_request(struct tegra_dma_channel *tdc,
572 struct tegra_dma_sg_req *last_sg_req, bool to_terminate)
573 {
574 struct tegra_dma_sg_req *hsgreq = NULL;
575
576 if (list_empty(&tdc->pending_sg_req)) {
577 dev_err(tdc2dev(tdc), "Dma is running without req\n");
578 tegra_dma_stop(tdc);
579 return false;
580 }
581
582 /*
583 * Check that head req on list should be in flight.
584 * If it is not in flight then abort transfer as
585 * looping of transfer can not continue.
586 */
587 hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
588 if (!hsgreq->configured) {
589 tegra_dma_stop(tdc);
590 dev_err(tdc2dev(tdc), "Error in dma transfer, aborting dma\n");
591 tegra_dma_abort_all(tdc);
592 return false;
593 }
594
595 /* Configure next request */
596 if (!to_terminate)
597 tdc_configure_next_head_desc(tdc);
598 return true;
599 }
600
601 static void handle_once_dma_done(struct tegra_dma_channel *tdc,
602 bool to_terminate)
603 {
604 struct tegra_dma_sg_req *sgreq;
605 struct tegra_dma_desc *dma_desc;
606
607 tdc->busy = false;
608 sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
609 dma_desc = sgreq->dma_desc;
610 dma_desc->bytes_transferred += sgreq->req_len;
611
612 list_del(&sgreq->node);
613 if (sgreq->last_sg) {
614 dma_desc->dma_status = DMA_COMPLETE;
615 dma_cookie_complete(&dma_desc->txd);
616 if (!dma_desc->cb_count)
617 list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
618 dma_desc->cb_count++;
619 list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
620 }
621 list_add_tail(&sgreq->node, &tdc->free_sg_req);
622
623 /* Do not start DMA if it is going to be terminate */
624 if (to_terminate || list_empty(&tdc->pending_sg_req))
625 return;
626
627 tdc_start_head_req(tdc);
628 }
629
630 static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc,
631 bool to_terminate)
632 {
633 struct tegra_dma_sg_req *sgreq;
634 struct tegra_dma_desc *dma_desc;
635 bool st;
636
637 sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
638 dma_desc = sgreq->dma_desc;
639 dma_desc->bytes_transferred += sgreq->req_len;
640
641 /* Callback need to be call */
642 if (!dma_desc->cb_count)
643 list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
644 dma_desc->cb_count++;
645
646 /* If not last req then put at end of pending list */
647 if (!list_is_last(&sgreq->node, &tdc->pending_sg_req)) {
648 list_move_tail(&sgreq->node, &tdc->pending_sg_req);
649 sgreq->configured = false;
650 st = handle_continuous_head_request(tdc, sgreq, to_terminate);
651 if (!st)
652 dma_desc->dma_status = DMA_ERROR;
653 }
654 }
655
656 static void tegra_dma_tasklet(unsigned long data)
657 {
658 struct tegra_dma_channel *tdc = (struct tegra_dma_channel *)data;
659 struct dmaengine_desc_callback cb;
660 struct tegra_dma_desc *dma_desc;
661 unsigned long flags;
662 int cb_count;
663
664 spin_lock_irqsave(&tdc->lock, flags);
665 while (!list_empty(&tdc->cb_desc)) {
666 dma_desc = list_first_entry(&tdc->cb_desc,
667 typeof(*dma_desc), cb_node);
668 list_del(&dma_desc->cb_node);
669 dmaengine_desc_get_callback(&dma_desc->txd, &cb);
670 cb_count = dma_desc->cb_count;
671 dma_desc->cb_count = 0;
672 spin_unlock_irqrestore(&tdc->lock, flags);
673 while (cb_count--)
674 dmaengine_desc_callback_invoke(&cb, NULL);
675 spin_lock_irqsave(&tdc->lock, flags);
676 }
677 spin_unlock_irqrestore(&tdc->lock, flags);
678 }
679
680 static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
681 {
682 struct tegra_dma_channel *tdc = dev_id;
683 unsigned long status;
684 unsigned long flags;
685
686 spin_lock_irqsave(&tdc->lock, flags);
687
688 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
689 if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
690 tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status);
691 tdc->isr_handler(tdc, false);
692 tasklet_schedule(&tdc->tasklet);
693 spin_unlock_irqrestore(&tdc->lock, flags);
694 return IRQ_HANDLED;
695 }
696
697 spin_unlock_irqrestore(&tdc->lock, flags);
698 dev_info(tdc2dev(tdc),
699 "Interrupt already served status 0x%08lx\n", status);
700 return IRQ_NONE;
701 }
702
703 static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *txd)
704 {
705 struct tegra_dma_desc *dma_desc = txd_to_tegra_dma_desc(txd);
706 struct tegra_dma_channel *tdc = to_tegra_dma_chan(txd->chan);
707 unsigned long flags;
708 dma_cookie_t cookie;
709
710 spin_lock_irqsave(&tdc->lock, flags);
711 dma_desc->dma_status = DMA_IN_PROGRESS;
712 cookie = dma_cookie_assign(&dma_desc->txd);
713 list_splice_tail_init(&dma_desc->tx_list, &tdc->pending_sg_req);
714 spin_unlock_irqrestore(&tdc->lock, flags);
715 return cookie;
716 }
717
718 static void tegra_dma_issue_pending(struct dma_chan *dc)
719 {
720 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
721 unsigned long flags;
722
723 spin_lock_irqsave(&tdc->lock, flags);
724 if (list_empty(&tdc->pending_sg_req)) {
725 dev_err(tdc2dev(tdc), "No DMA request\n");
726 goto end;
727 }
728 if (!tdc->busy) {
729 tdc_start_head_req(tdc);
730
731 /* Continuous single mode: Configure next req */
732 if (tdc->cyclic) {
733 /*
734 * Wait for 1 burst time for configure DMA for
735 * next transfer.
736 */
737 udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
738 tdc_configure_next_head_desc(tdc);
739 }
740 }
741 end:
742 spin_unlock_irqrestore(&tdc->lock, flags);
743 }
744
745 static int tegra_dma_terminate_all(struct dma_chan *dc)
746 {
747 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
748 struct tegra_dma_sg_req *sgreq;
749 struct tegra_dma_desc *dma_desc;
750 unsigned long flags;
751 unsigned long status;
752 unsigned long wcount;
753 bool was_busy;
754
755 spin_lock_irqsave(&tdc->lock, flags);
756 if (list_empty(&tdc->pending_sg_req)) {
757 spin_unlock_irqrestore(&tdc->lock, flags);
758 return 0;
759 }
760
761 if (!tdc->busy)
762 goto skip_dma_stop;
763
764 /* Pause DMA before checking the queue status */
765 tegra_dma_pause(tdc, true);
766
767 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
768 if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
769 dev_dbg(tdc2dev(tdc), "%s():handling isr\n", __func__);
770 tdc->isr_handler(tdc, true);
771 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
772 }
773 if (tdc->tdma->chip_data->support_separate_wcount_reg)
774 wcount = tdc_read(tdc, TEGRA_APBDMA_CHAN_WORD_TRANSFER);
775 else
776 wcount = status;
777
778 was_busy = tdc->busy;
779 tegra_dma_stop(tdc);
780
781 if (!list_empty(&tdc->pending_sg_req) && was_busy) {
782 sgreq = list_first_entry(&tdc->pending_sg_req,
783 typeof(*sgreq), node);
784 sgreq->dma_desc->bytes_transferred +=
785 get_current_xferred_count(tdc, sgreq, wcount);
786 }
787 tegra_dma_resume(tdc);
788
789 skip_dma_stop:
790 tegra_dma_abort_all(tdc);
791
792 while (!list_empty(&tdc->cb_desc)) {
793 dma_desc = list_first_entry(&tdc->cb_desc,
794 typeof(*dma_desc), cb_node);
795 list_del(&dma_desc->cb_node);
796 dma_desc->cb_count = 0;
797 }
798 spin_unlock_irqrestore(&tdc->lock, flags);
799 return 0;
800 }
801
802 static enum dma_status tegra_dma_tx_status(struct dma_chan *dc,
803 dma_cookie_t cookie, struct dma_tx_state *txstate)
804 {
805 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
806 struct tegra_dma_desc *dma_desc;
807 struct tegra_dma_sg_req *sg_req;
808 enum dma_status ret;
809 unsigned long flags;
810 unsigned int residual;
811
812 ret = dma_cookie_status(dc, cookie, txstate);
813 if (ret == DMA_COMPLETE)
814 return ret;
815
816 spin_lock_irqsave(&tdc->lock, flags);
817
818 /* Check on wait_ack desc status */
819 list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
820 if (dma_desc->txd.cookie == cookie) {
821 ret = dma_desc->dma_status;
822 goto found;
823 }
824 }
825
826 /* Check in pending list */
827 list_for_each_entry(sg_req, &tdc->pending_sg_req, node) {
828 dma_desc = sg_req->dma_desc;
829 if (dma_desc->txd.cookie == cookie) {
830 ret = dma_desc->dma_status;
831 goto found;
832 }
833 }
834
835 dev_dbg(tdc2dev(tdc), "cookie %d not found\n", cookie);
836 dma_desc = NULL;
837
838 found:
839 if (dma_desc && txstate) {
840 residual = dma_desc->bytes_requested -
841 (dma_desc->bytes_transferred %
842 dma_desc->bytes_requested);
843 dma_set_residue(txstate, residual);
844 }
845
846 spin_unlock_irqrestore(&tdc->lock, flags);
847 return ret;
848 }
849
850 static inline int get_bus_width(struct tegra_dma_channel *tdc,
851 enum dma_slave_buswidth slave_bw)
852 {
853 switch (slave_bw) {
854 case DMA_SLAVE_BUSWIDTH_1_BYTE:
855 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8;
856 case DMA_SLAVE_BUSWIDTH_2_BYTES:
857 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16;
858 case DMA_SLAVE_BUSWIDTH_4_BYTES:
859 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32;
860 case DMA_SLAVE_BUSWIDTH_8_BYTES:
861 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64;
862 default:
863 dev_warn(tdc2dev(tdc),
864 "slave bw is not supported, using 32bits\n");
865 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32;
866 }
867 }
868
869 static inline int get_burst_size(struct tegra_dma_channel *tdc,
870 u32 burst_size, enum dma_slave_buswidth slave_bw, int len)
871 {
872 int burst_byte;
873 int burst_ahb_width;
874
875 /*
876 * burst_size from client is in terms of the bus_width.
877 * convert them into AHB memory width which is 4 byte.
878 */
879 burst_byte = burst_size * slave_bw;
880 burst_ahb_width = burst_byte / 4;
881
882 /* If burst size is 0 then calculate the burst size based on length */
883 if (!burst_ahb_width) {
884 if (len & 0xF)
885 return TEGRA_APBDMA_AHBSEQ_BURST_1;
886 else if ((len >> 4) & 0x1)
887 return TEGRA_APBDMA_AHBSEQ_BURST_4;
888 else
889 return TEGRA_APBDMA_AHBSEQ_BURST_8;
890 }
891 if (burst_ahb_width < 4)
892 return TEGRA_APBDMA_AHBSEQ_BURST_1;
893 else if (burst_ahb_width < 8)
894 return TEGRA_APBDMA_AHBSEQ_BURST_4;
895 else
896 return TEGRA_APBDMA_AHBSEQ_BURST_8;
897 }
898
899 static int get_transfer_param(struct tegra_dma_channel *tdc,
900 enum dma_transfer_direction direction, unsigned long *apb_addr,
901 unsigned long *apb_seq, unsigned long *csr, unsigned int *burst_size,
902 enum dma_slave_buswidth *slave_bw)
903 {
904 switch (direction) {
905 case DMA_MEM_TO_DEV:
906 *apb_addr = tdc->dma_sconfig.dst_addr;
907 *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.dst_addr_width);
908 *burst_size = tdc->dma_sconfig.dst_maxburst;
909 *slave_bw = tdc->dma_sconfig.dst_addr_width;
910 *csr = TEGRA_APBDMA_CSR_DIR;
911 return 0;
912
913 case DMA_DEV_TO_MEM:
914 *apb_addr = tdc->dma_sconfig.src_addr;
915 *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.src_addr_width);
916 *burst_size = tdc->dma_sconfig.src_maxburst;
917 *slave_bw = tdc->dma_sconfig.src_addr_width;
918 *csr = 0;
919 return 0;
920
921 default:
922 dev_err(tdc2dev(tdc), "Dma direction is not supported\n");
923 return -EINVAL;
924 }
925 return -EINVAL;
926 }
927
928 static void tegra_dma_prep_wcount(struct tegra_dma_channel *tdc,
929 struct tegra_dma_channel_regs *ch_regs, u32 len)
930 {
931 u32 len_field = (len - 4) & 0xFFFC;
932
933 if (tdc->tdma->chip_data->support_separate_wcount_reg)
934 ch_regs->wcount = len_field;
935 else
936 ch_regs->csr |= len_field;
937 }
938
939 static struct dma_async_tx_descriptor *tegra_dma_prep_slave_sg(
940 struct dma_chan *dc, struct scatterlist *sgl, unsigned int sg_len,
941 enum dma_transfer_direction direction, unsigned long flags,
942 void *context)
943 {
944 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
945 struct tegra_dma_desc *dma_desc;
946 unsigned int i;
947 struct scatterlist *sg;
948 unsigned long csr, ahb_seq, apb_ptr, apb_seq;
949 struct list_head req_list;
950 struct tegra_dma_sg_req *sg_req = NULL;
951 u32 burst_size;
952 enum dma_slave_buswidth slave_bw;
953
954 if (!tdc->config_init) {
955 dev_err(tdc2dev(tdc), "dma channel is not configured\n");
956 return NULL;
957 }
958 if (sg_len < 1) {
959 dev_err(tdc2dev(tdc), "Invalid segment length %d\n", sg_len);
960 return NULL;
961 }
962
963 if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr,
964 &burst_size, &slave_bw) < 0)
965 return NULL;
966
967 INIT_LIST_HEAD(&req_list);
968
969 ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB;
970 ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE <<
971 TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT;
972 ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32;
973
974 csr |= TEGRA_APBDMA_CSR_ONCE;
975
976 if (tdc->slave_id != TEGRA_APBDMA_SLAVE_ID_INVALID) {
977 csr |= TEGRA_APBDMA_CSR_FLOW;
978 csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
979 }
980
981 if (flags & DMA_PREP_INTERRUPT)
982 csr |= TEGRA_APBDMA_CSR_IE_EOC;
983
984 apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1;
985
986 dma_desc = tegra_dma_desc_get(tdc);
987 if (!dma_desc) {
988 dev_err(tdc2dev(tdc), "Dma descriptors not available\n");
989 return NULL;
990 }
991 INIT_LIST_HEAD(&dma_desc->tx_list);
992 INIT_LIST_HEAD(&dma_desc->cb_node);
993 dma_desc->cb_count = 0;
994 dma_desc->bytes_requested = 0;
995 dma_desc->bytes_transferred = 0;
996 dma_desc->dma_status = DMA_IN_PROGRESS;
997
998 /* Make transfer requests */
999 for_each_sg(sgl, sg, sg_len, i) {
1000 u32 len, mem;
1001
1002 mem = sg_dma_address(sg);
1003 len = sg_dma_len(sg);
1004
1005 if ((len & 3) || (mem & 3) ||
1006 (len > tdc->tdma->chip_data->max_dma_count)) {
1007 dev_err(tdc2dev(tdc),
1008 "Dma length/memory address is not supported\n");
1009 tegra_dma_desc_put(tdc, dma_desc);
1010 return NULL;
1011 }
1012
1013 sg_req = tegra_dma_sg_req_get(tdc);
1014 if (!sg_req) {
1015 dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
1016 tegra_dma_desc_put(tdc, dma_desc);
1017 return NULL;
1018 }
1019
1020 ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
1021 dma_desc->bytes_requested += len;
1022
1023 sg_req->ch_regs.apb_ptr = apb_ptr;
1024 sg_req->ch_regs.ahb_ptr = mem;
1025 sg_req->ch_regs.csr = csr;
1026 tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len);
1027 sg_req->ch_regs.apb_seq = apb_seq;
1028 sg_req->ch_regs.ahb_seq = ahb_seq;
1029 sg_req->configured = false;
1030 sg_req->last_sg = false;
1031 sg_req->dma_desc = dma_desc;
1032 sg_req->req_len = len;
1033
1034 list_add_tail(&sg_req->node, &dma_desc->tx_list);
1035 }
1036 sg_req->last_sg = true;
1037 if (flags & DMA_CTRL_ACK)
1038 dma_desc->txd.flags = DMA_CTRL_ACK;
1039
1040 /*
1041 * Make sure that mode should not be conflicting with currently
1042 * configured mode.
1043 */
1044 if (!tdc->isr_handler) {
1045 tdc->isr_handler = handle_once_dma_done;
1046 tdc->cyclic = false;
1047 } else {
1048 if (tdc->cyclic) {
1049 dev_err(tdc2dev(tdc), "DMA configured in cyclic mode\n");
1050 tegra_dma_desc_put(tdc, dma_desc);
1051 return NULL;
1052 }
1053 }
1054
1055 return &dma_desc->txd;
1056 }
1057
1058 static struct dma_async_tx_descriptor *tegra_dma_prep_dma_cyclic(
1059 struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len,
1060 size_t period_len, enum dma_transfer_direction direction,
1061 unsigned long flags)
1062 {
1063 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1064 struct tegra_dma_desc *dma_desc = NULL;
1065 struct tegra_dma_sg_req *sg_req = NULL;
1066 unsigned long csr, ahb_seq, apb_ptr, apb_seq;
1067 int len;
1068 size_t remain_len;
1069 dma_addr_t mem = buf_addr;
1070 u32 burst_size;
1071 enum dma_slave_buswidth slave_bw;
1072
1073 if (!buf_len || !period_len) {
1074 dev_err(tdc2dev(tdc), "Invalid buffer/period len\n");
1075 return NULL;
1076 }
1077
1078 if (!tdc->config_init) {
1079 dev_err(tdc2dev(tdc), "DMA slave is not configured\n");
1080 return NULL;
1081 }
1082
1083 /*
1084 * We allow to take more number of requests till DMA is
1085 * not started. The driver will loop over all requests.
1086 * Once DMA is started then new requests can be queued only after
1087 * terminating the DMA.
1088 */
1089 if (tdc->busy) {
1090 dev_err(tdc2dev(tdc), "Request not allowed when dma running\n");
1091 return NULL;
1092 }
1093
1094 /*
1095 * We only support cycle transfer when buf_len is multiple of
1096 * period_len.
1097 */
1098 if (buf_len % period_len) {
1099 dev_err(tdc2dev(tdc), "buf_len is not multiple of period_len\n");
1100 return NULL;
1101 }
1102
1103 len = period_len;
1104 if ((len & 3) || (buf_addr & 3) ||
1105 (len > tdc->tdma->chip_data->max_dma_count)) {
1106 dev_err(tdc2dev(tdc), "Req len/mem address is not correct\n");
1107 return NULL;
1108 }
1109
1110 if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr,
1111 &burst_size, &slave_bw) < 0)
1112 return NULL;
1113
1114 ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB;
1115 ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE <<
1116 TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT;
1117 ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32;
1118
1119 if (tdc->slave_id != TEGRA_APBDMA_SLAVE_ID_INVALID) {
1120 csr |= TEGRA_APBDMA_CSR_FLOW;
1121 csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
1122 }
1123
1124 if (flags & DMA_PREP_INTERRUPT)
1125 csr |= TEGRA_APBDMA_CSR_IE_EOC;
1126
1127 apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1;
1128
1129 dma_desc = tegra_dma_desc_get(tdc);
1130 if (!dma_desc) {
1131 dev_err(tdc2dev(tdc), "not enough descriptors available\n");
1132 return NULL;
1133 }
1134
1135 INIT_LIST_HEAD(&dma_desc->tx_list);
1136 INIT_LIST_HEAD(&dma_desc->cb_node);
1137 dma_desc->cb_count = 0;
1138
1139 dma_desc->bytes_transferred = 0;
1140 dma_desc->bytes_requested = buf_len;
1141 remain_len = buf_len;
1142
1143 /* Split transfer equal to period size */
1144 while (remain_len) {
1145 sg_req = tegra_dma_sg_req_get(tdc);
1146 if (!sg_req) {
1147 dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
1148 tegra_dma_desc_put(tdc, dma_desc);
1149 return NULL;
1150 }
1151
1152 ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
1153 sg_req->ch_regs.apb_ptr = apb_ptr;
1154 sg_req->ch_regs.ahb_ptr = mem;
1155 sg_req->ch_regs.csr = csr;
1156 tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len);
1157 sg_req->ch_regs.apb_seq = apb_seq;
1158 sg_req->ch_regs.ahb_seq = ahb_seq;
1159 sg_req->configured = false;
1160 sg_req->last_sg = false;
1161 sg_req->dma_desc = dma_desc;
1162 sg_req->req_len = len;
1163
1164 list_add_tail(&sg_req->node, &dma_desc->tx_list);
1165 remain_len -= len;
1166 mem += len;
1167 }
1168 sg_req->last_sg = true;
1169 if (flags & DMA_CTRL_ACK)
1170 dma_desc->txd.flags = DMA_CTRL_ACK;
1171
1172 /*
1173 * Make sure that mode should not be conflicting with currently
1174 * configured mode.
1175 */
1176 if (!tdc->isr_handler) {
1177 tdc->isr_handler = handle_cont_sngl_cycle_dma_done;
1178 tdc->cyclic = true;
1179 } else {
1180 if (!tdc->cyclic) {
1181 dev_err(tdc2dev(tdc), "DMA configuration conflict\n");
1182 tegra_dma_desc_put(tdc, dma_desc);
1183 return NULL;
1184 }
1185 }
1186
1187 return &dma_desc->txd;
1188 }
1189
1190 static int tegra_dma_alloc_chan_resources(struct dma_chan *dc)
1191 {
1192 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1193 struct tegra_dma *tdma = tdc->tdma;
1194 int ret;
1195
1196 dma_cookie_init(&tdc->dma_chan);
1197 tdc->config_init = false;
1198
1199 ret = pm_runtime_get_sync(tdma->dev);
1200 if (ret < 0)
1201 return ret;
1202
1203 return 0;
1204 }
1205
1206 static void tegra_dma_free_chan_resources(struct dma_chan *dc)
1207 {
1208 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1209 struct tegra_dma *tdma = tdc->tdma;
1210 struct tegra_dma_desc *dma_desc;
1211 struct tegra_dma_sg_req *sg_req;
1212 struct list_head dma_desc_list;
1213 struct list_head sg_req_list;
1214 unsigned long flags;
1215
1216 INIT_LIST_HEAD(&dma_desc_list);
1217 INIT_LIST_HEAD(&sg_req_list);
1218
1219 dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id);
1220
1221 if (tdc->busy)
1222 tegra_dma_terminate_all(dc);
1223
1224 spin_lock_irqsave(&tdc->lock, flags);
1225 list_splice_init(&tdc->pending_sg_req, &sg_req_list);
1226 list_splice_init(&tdc->free_sg_req, &sg_req_list);
1227 list_splice_init(&tdc->free_dma_desc, &dma_desc_list);
1228 INIT_LIST_HEAD(&tdc->cb_desc);
1229 tdc->config_init = false;
1230 tdc->isr_handler = NULL;
1231 spin_unlock_irqrestore(&tdc->lock, flags);
1232
1233 while (!list_empty(&dma_desc_list)) {
1234 dma_desc = list_first_entry(&dma_desc_list,
1235 typeof(*dma_desc), node);
1236 list_del(&dma_desc->node);
1237 kfree(dma_desc);
1238 }
1239
1240 while (!list_empty(&sg_req_list)) {
1241 sg_req = list_first_entry(&sg_req_list, typeof(*sg_req), node);
1242 list_del(&sg_req->node);
1243 kfree(sg_req);
1244 }
1245 pm_runtime_put(tdma->dev);
1246
1247 tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID;
1248 }
1249
1250 static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
1251 struct of_dma *ofdma)
1252 {
1253 struct tegra_dma *tdma = ofdma->of_dma_data;
1254 struct dma_chan *chan;
1255 struct tegra_dma_channel *tdc;
1256
1257 if (dma_spec->args[0] > TEGRA_APBDMA_CSR_REQ_SEL_MASK) {
1258 dev_err(tdma->dev, "Invalid slave id: %d\n", dma_spec->args[0]);
1259 return NULL;
1260 }
1261
1262 chan = dma_get_any_slave_channel(&tdma->dma_dev);
1263 if (!chan)
1264 return NULL;
1265
1266 tdc = to_tegra_dma_chan(chan);
1267 tdc->slave_id = dma_spec->args[0];
1268
1269 return chan;
1270 }
1271
1272 /* Tegra20 specific DMA controller information */
1273 static const struct tegra_dma_chip_data tegra20_dma_chip_data = {
1274 .nr_channels = 16,
1275 .channel_reg_size = 0x20,
1276 .max_dma_count = 1024UL * 64,
1277 .support_channel_pause = false,
1278 .support_separate_wcount_reg = false,
1279 };
1280
1281 /* Tegra30 specific DMA controller information */
1282 static const struct tegra_dma_chip_data tegra30_dma_chip_data = {
1283 .nr_channels = 32,
1284 .channel_reg_size = 0x20,
1285 .max_dma_count = 1024UL * 64,
1286 .support_channel_pause = false,
1287 .support_separate_wcount_reg = false,
1288 };
1289
1290 /* Tegra114 specific DMA controller information */
1291 static const struct tegra_dma_chip_data tegra114_dma_chip_data = {
1292 .nr_channels = 32,
1293 .channel_reg_size = 0x20,
1294 .max_dma_count = 1024UL * 64,
1295 .support_channel_pause = true,
1296 .support_separate_wcount_reg = false,
1297 };
1298
1299 /* Tegra148 specific DMA controller information */
1300 static const struct tegra_dma_chip_data tegra148_dma_chip_data = {
1301 .nr_channels = 32,
1302 .channel_reg_size = 0x40,
1303 .max_dma_count = 1024UL * 64,
1304 .support_channel_pause = true,
1305 .support_separate_wcount_reg = true,
1306 };
1307
1308 static int tegra_dma_probe(struct platform_device *pdev)
1309 {
1310 struct resource *res;
1311 struct tegra_dma *tdma;
1312 int ret;
1313 int i;
1314 const struct tegra_dma_chip_data *cdata;
1315
1316 cdata = of_device_get_match_data(&pdev->dev);
1317 if (!cdata) {
1318 dev_err(&pdev->dev, "Error: No device match data found\n");
1319 return -ENODEV;
1320 }
1321
1322 tdma = devm_kzalloc(&pdev->dev, sizeof(*tdma) + cdata->nr_channels *
1323 sizeof(struct tegra_dma_channel), GFP_KERNEL);
1324 if (!tdma)
1325 return -ENOMEM;
1326
1327 tdma->dev = &pdev->dev;
1328 tdma->chip_data = cdata;
1329 platform_set_drvdata(pdev, tdma);
1330
1331 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1332 tdma->base_addr = devm_ioremap_resource(&pdev->dev, res);
1333 if (IS_ERR(tdma->base_addr))
1334 return PTR_ERR(tdma->base_addr);
1335
1336 tdma->dma_clk = devm_clk_get(&pdev->dev, NULL);
1337 if (IS_ERR(tdma->dma_clk)) {
1338 dev_err(&pdev->dev, "Error: Missing controller clock\n");
1339 return PTR_ERR(tdma->dma_clk);
1340 }
1341
1342 tdma->rst = devm_reset_control_get(&pdev->dev, "dma");
1343 if (IS_ERR(tdma->rst)) {
1344 dev_err(&pdev->dev, "Error: Missing reset\n");
1345 return PTR_ERR(tdma->rst);
1346 }
1347
1348 spin_lock_init(&tdma->global_lock);
1349
1350 pm_runtime_enable(&pdev->dev);
1351 if (!pm_runtime_enabled(&pdev->dev))
1352 ret = tegra_dma_runtime_resume(&pdev->dev);
1353 else
1354 ret = pm_runtime_get_sync(&pdev->dev);
1355
1356 if (ret < 0) {
1357 pm_runtime_disable(&pdev->dev);
1358 return ret;
1359 }
1360
1361 /* Reset DMA controller */
1362 reset_control_assert(tdma->rst);
1363 udelay(2);
1364 reset_control_deassert(tdma->rst);
1365
1366 /* Enable global DMA registers */
1367 tdma_write(tdma, TEGRA_APBDMA_GENERAL, TEGRA_APBDMA_GENERAL_ENABLE);
1368 tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0);
1369 tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul);
1370
1371 pm_runtime_put(&pdev->dev);
1372
1373 INIT_LIST_HEAD(&tdma->dma_dev.channels);
1374 for (i = 0; i < cdata->nr_channels; i++) {
1375 struct tegra_dma_channel *tdc = &tdma->channels[i];
1376
1377 tdc->chan_addr = tdma->base_addr +
1378 TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET +
1379 (i * cdata->channel_reg_size);
1380
1381 res = platform_get_resource(pdev, IORESOURCE_IRQ, i);
1382 if (!res) {
1383 ret = -EINVAL;
1384 dev_err(&pdev->dev, "No irq resource for chan %d\n", i);
1385 goto err_irq;
1386 }
1387 tdc->irq = res->start;
1388 snprintf(tdc->name, sizeof(tdc->name), "apbdma.%d", i);
1389 ret = request_irq(tdc->irq, tegra_dma_isr, 0, tdc->name, tdc);
1390 if (ret) {
1391 dev_err(&pdev->dev,
1392 "request_irq failed with err %d channel %d\n",
1393 ret, i);
1394 goto err_irq;
1395 }
1396
1397 tdc->dma_chan.device = &tdma->dma_dev;
1398 dma_cookie_init(&tdc->dma_chan);
1399 list_add_tail(&tdc->dma_chan.device_node,
1400 &tdma->dma_dev.channels);
1401 tdc->tdma = tdma;
1402 tdc->id = i;
1403 tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID;
1404
1405 tasklet_init(&tdc->tasklet, tegra_dma_tasklet,
1406 (unsigned long)tdc);
1407 spin_lock_init(&tdc->lock);
1408
1409 INIT_LIST_HEAD(&tdc->pending_sg_req);
1410 INIT_LIST_HEAD(&tdc->free_sg_req);
1411 INIT_LIST_HEAD(&tdc->free_dma_desc);
1412 INIT_LIST_HEAD(&tdc->cb_desc);
1413 }
1414
1415 dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask);
1416 dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask);
1417 dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask);
1418
1419 tdma->global_pause_count = 0;
1420 tdma->dma_dev.dev = &pdev->dev;
1421 tdma->dma_dev.device_alloc_chan_resources =
1422 tegra_dma_alloc_chan_resources;
1423 tdma->dma_dev.device_free_chan_resources =
1424 tegra_dma_free_chan_resources;
1425 tdma->dma_dev.device_prep_slave_sg = tegra_dma_prep_slave_sg;
1426 tdma->dma_dev.device_prep_dma_cyclic = tegra_dma_prep_dma_cyclic;
1427 tdma->dma_dev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1428 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1429 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1430 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
1431 tdma->dma_dev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1432 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1433 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1434 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
1435 tdma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1436 /*
1437 * XXX The hardware appears to support
1438 * DMA_RESIDUE_GRANULARITY_BURST-level reporting, but it's
1439 * only used by this driver during tegra_dma_terminate_all()
1440 */
1441 tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
1442 tdma->dma_dev.device_config = tegra_dma_slave_config;
1443 tdma->dma_dev.device_terminate_all = tegra_dma_terminate_all;
1444 tdma->dma_dev.device_tx_status = tegra_dma_tx_status;
1445 tdma->dma_dev.device_issue_pending = tegra_dma_issue_pending;
1446
1447 ret = dma_async_device_register(&tdma->dma_dev);
1448 if (ret < 0) {
1449 dev_err(&pdev->dev,
1450 "Tegra20 APB DMA driver registration failed %d\n", ret);
1451 goto err_irq;
1452 }
1453
1454 ret = of_dma_controller_register(pdev->dev.of_node,
1455 tegra_dma_of_xlate, tdma);
1456 if (ret < 0) {
1457 dev_err(&pdev->dev,
1458 "Tegra20 APB DMA OF registration failed %d\n", ret);
1459 goto err_unregister_dma_dev;
1460 }
1461
1462 dev_info(&pdev->dev, "Tegra20 APB DMA driver register %d channels\n",
1463 cdata->nr_channels);
1464 return 0;
1465
1466 err_unregister_dma_dev:
1467 dma_async_device_unregister(&tdma->dma_dev);
1468 err_irq:
1469 while (--i >= 0) {
1470 struct tegra_dma_channel *tdc = &tdma->channels[i];
1471
1472 free_irq(tdc->irq, tdc);
1473 tasklet_kill(&tdc->tasklet);
1474 }
1475
1476 pm_runtime_disable(&pdev->dev);
1477 if (!pm_runtime_status_suspended(&pdev->dev))
1478 tegra_dma_runtime_suspend(&pdev->dev);
1479 return ret;
1480 }
1481
1482 static int tegra_dma_remove(struct platform_device *pdev)
1483 {
1484 struct tegra_dma *tdma = platform_get_drvdata(pdev);
1485 int i;
1486 struct tegra_dma_channel *tdc;
1487
1488 dma_async_device_unregister(&tdma->dma_dev);
1489
1490 for (i = 0; i < tdma->chip_data->nr_channels; ++i) {
1491 tdc = &tdma->channels[i];
1492 free_irq(tdc->irq, tdc);
1493 tasklet_kill(&tdc->tasklet);
1494 }
1495
1496 pm_runtime_disable(&pdev->dev);
1497 if (!pm_runtime_status_suspended(&pdev->dev))
1498 tegra_dma_runtime_suspend(&pdev->dev);
1499
1500 return 0;
1501 }
1502
1503 static int tegra_dma_runtime_suspend(struct device *dev)
1504 {
1505 struct tegra_dma *tdma = dev_get_drvdata(dev);
1506 int i;
1507
1508 tdma->reg_gen = tdma_read(tdma, TEGRA_APBDMA_GENERAL);
1509 for (i = 0; i < tdma->chip_data->nr_channels; i++) {
1510 struct tegra_dma_channel *tdc = &tdma->channels[i];
1511 struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg;
1512
1513 /* Only save the state of DMA channels that are in use */
1514 if (!tdc->config_init)
1515 continue;
1516
1517 ch_reg->csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR);
1518 ch_reg->ahb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBPTR);
1519 ch_reg->apb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBPTR);
1520 ch_reg->ahb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBSEQ);
1521 ch_reg->apb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBSEQ);
1522 if (tdma->chip_data->support_separate_wcount_reg)
1523 ch_reg->wcount = tdc_read(tdc,
1524 TEGRA_APBDMA_CHAN_WCOUNT);
1525 }
1526
1527 clk_disable_unprepare(tdma->dma_clk);
1528
1529 return 0;
1530 }
1531
1532 static int tegra_dma_runtime_resume(struct device *dev)
1533 {
1534 struct tegra_dma *tdma = dev_get_drvdata(dev);
1535 int i, ret;
1536
1537 ret = clk_prepare_enable(tdma->dma_clk);
1538 if (ret < 0) {
1539 dev_err(dev, "clk_enable failed: %d\n", ret);
1540 return ret;
1541 }
1542
1543 tdma_write(tdma, TEGRA_APBDMA_GENERAL, tdma->reg_gen);
1544 tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0);
1545 tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul);
1546
1547 for (i = 0; i < tdma->chip_data->nr_channels; i++) {
1548 struct tegra_dma_channel *tdc = &tdma->channels[i];
1549 struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg;
1550
1551 /* Only restore the state of DMA channels that are in use */
1552 if (!tdc->config_init)
1553 continue;
1554
1555 if (tdma->chip_data->support_separate_wcount_reg)
1556 tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT,
1557 ch_reg->wcount);
1558 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_reg->apb_seq);
1559 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_reg->apb_ptr);
1560 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_reg->ahb_seq);
1561 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_reg->ahb_ptr);
1562 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
1563 (ch_reg->csr & ~TEGRA_APBDMA_CSR_ENB));
1564 }
1565
1566 return 0;
1567 }
1568
1569 static const struct dev_pm_ops tegra_dma_dev_pm_ops = {
1570 SET_RUNTIME_PM_OPS(tegra_dma_runtime_suspend, tegra_dma_runtime_resume,
1571 NULL)
1572 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
1573 pm_runtime_force_resume)
1574 };
1575
1576 static const struct of_device_id tegra_dma_of_match[] = {
1577 {
1578 .compatible = "nvidia,tegra148-apbdma",
1579 .data = &tegra148_dma_chip_data,
1580 }, {
1581 .compatible = "nvidia,tegra114-apbdma",
1582 .data = &tegra114_dma_chip_data,
1583 }, {
1584 .compatible = "nvidia,tegra30-apbdma",
1585 .data = &tegra30_dma_chip_data,
1586 }, {
1587 .compatible = "nvidia,tegra20-apbdma",
1588 .data = &tegra20_dma_chip_data,
1589 }, {
1590 },
1591 };
1592 MODULE_DEVICE_TABLE(of, tegra_dma_of_match);
1593
1594 static struct platform_driver tegra_dmac_driver = {
1595 .driver = {
1596 .name = "tegra-apbdma",
1597 .pm = &tegra_dma_dev_pm_ops,
1598 .of_match_table = tegra_dma_of_match,
1599 },
1600 .probe = tegra_dma_probe,
1601 .remove = tegra_dma_remove,
1602 };
1603
1604 module_platform_driver(tegra_dmac_driver);
1605
1606 MODULE_ALIAS("platform:tegra20-apbdma");
1607 MODULE_DESCRIPTION("NVIDIA Tegra APB DMA Controller driver");
1608 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
1609 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support