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ceph: choose readdir frag based on previous readdir reply
[linux/fpc-iii.git] / drivers / dma / tegra20-apb-dma.c
blob3722b9d8d9fe203124ead98c5fc823da84d4bf84
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 if (sconfig->slave_id > TEGRA_APBDMA_CSR_REQ_SEL_MASK)
358 return -EINVAL;
359 tdc->slave_id = sconfig->slave_id;
360 }
361 tdc->config_init = true;
362 return 0;
363 }
364
365 static void tegra_dma_global_pause(struct tegra_dma_channel *tdc,
366 bool wait_for_burst_complete)
367 {
368 struct tegra_dma *tdma = tdc->tdma;
369
370 spin_lock(&tdma->global_lock);
371
372 if (tdc->tdma->global_pause_count == 0) {
373 tdma_write(tdma, TEGRA_APBDMA_GENERAL, 0);
374 if (wait_for_burst_complete)
375 udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
376 }
377
378 tdc->tdma->global_pause_count++;
379
380 spin_unlock(&tdma->global_lock);
381 }
382
383 static void tegra_dma_global_resume(struct tegra_dma_channel *tdc)
384 {
385 struct tegra_dma *tdma = tdc->tdma;
386
387 spin_lock(&tdma->global_lock);
388
389 if (WARN_ON(tdc->tdma->global_pause_count == 0))
390 goto out;
391
392 if (--tdc->tdma->global_pause_count == 0)
393 tdma_write(tdma, TEGRA_APBDMA_GENERAL,
394 TEGRA_APBDMA_GENERAL_ENABLE);
395
396 out:
397 spin_unlock(&tdma->global_lock);
398 }
399
400 static void tegra_dma_pause(struct tegra_dma_channel *tdc,
401 bool wait_for_burst_complete)
402 {
403 struct tegra_dma *tdma = tdc->tdma;
404
405 if (tdma->chip_data->support_channel_pause) {
406 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE,
407 TEGRA_APBDMA_CHAN_CSRE_PAUSE);
408 if (wait_for_burst_complete)
409 udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
410 } else {
411 tegra_dma_global_pause(tdc, wait_for_burst_complete);
412 }
413 }
414
415 static void tegra_dma_resume(struct tegra_dma_channel *tdc)
416 {
417 struct tegra_dma *tdma = tdc->tdma;
418
419 if (tdma->chip_data->support_channel_pause) {
420 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE, 0);
421 } else {
422 tegra_dma_global_resume(tdc);
423 }
424 }
425
426 static void tegra_dma_stop(struct tegra_dma_channel *tdc)
427 {
428 u32 csr;
429 u32 status;
430
431 /* Disable interrupts */
432 csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR);
433 csr &= ~TEGRA_APBDMA_CSR_IE_EOC;
434 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr);
435
436 /* Disable DMA */
437 csr &= ~TEGRA_APBDMA_CSR_ENB;
438 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr);
439
440 /* Clear interrupt status if it is there */
441 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
442 if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
443 dev_dbg(tdc2dev(tdc), "%s():clearing interrupt\n", __func__);
444 tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status);
445 }
446 tdc->busy = false;
447 }
448
449 static void tegra_dma_start(struct tegra_dma_channel *tdc,
450 struct tegra_dma_sg_req *sg_req)
451 {
452 struct tegra_dma_channel_regs *ch_regs = &sg_req->ch_regs;
453
454 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, ch_regs->csr);
455 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_regs->apb_seq);
456 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_regs->apb_ptr);
457 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_regs->ahb_seq);
458 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_regs->ahb_ptr);
459 if (tdc->tdma->chip_data->support_separate_wcount_reg)
460 tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT, ch_regs->wcount);
461
462 /* Start DMA */
463 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
464 ch_regs->csr | TEGRA_APBDMA_CSR_ENB);
465 }
466
467 static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc,
468 struct tegra_dma_sg_req *nsg_req)
469 {
470 unsigned long status;
471
472 /*
473 * The DMA controller reloads the new configuration for next transfer
474 * after last burst of current transfer completes.
475 * If there is no IEC status then this makes sure that last burst
476 * has not be completed. There may be case that last burst is on
477 * flight and so it can complete but because DMA is paused, it
478 * will not generates interrupt as well as not reload the new
479 * configuration.
480 * If there is already IEC status then interrupt handler need to
481 * load new configuration.
482 */
483 tegra_dma_pause(tdc, false);
484 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
485
486 /*
487 * If interrupt is pending then do nothing as the ISR will handle
488 * the programing for new request.
489 */
490 if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
491 dev_err(tdc2dev(tdc),
492 "Skipping new configuration as interrupt is pending\n");
493 tegra_dma_resume(tdc);
494 return;
495 }
496
497 /* Safe to program new configuration */
498 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, nsg_req->ch_regs.apb_ptr);
499 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, nsg_req->ch_regs.ahb_ptr);
500 if (tdc->tdma->chip_data->support_separate_wcount_reg)
501 tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT,
502 nsg_req->ch_regs.wcount);
503 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
504 nsg_req->ch_regs.csr | TEGRA_APBDMA_CSR_ENB);
505 nsg_req->configured = true;
506
507 tegra_dma_resume(tdc);
508 }
509
510 static void tdc_start_head_req(struct tegra_dma_channel *tdc)
511 {
512 struct tegra_dma_sg_req *sg_req;
513
514 if (list_empty(&tdc->pending_sg_req))
515 return;
516
517 sg_req = list_first_entry(&tdc->pending_sg_req,
518 typeof(*sg_req), node);
519 tegra_dma_start(tdc, sg_req);
520 sg_req->configured = true;
521 tdc->busy = true;
522 }
523
524 static void tdc_configure_next_head_desc(struct tegra_dma_channel *tdc)
525 {
526 struct tegra_dma_sg_req *hsgreq;
527 struct tegra_dma_sg_req *hnsgreq;
528
529 if (list_empty(&tdc->pending_sg_req))
530 return;
531
532 hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
533 if (!list_is_last(&hsgreq->node, &tdc->pending_sg_req)) {
534 hnsgreq = list_first_entry(&hsgreq->node,
535 typeof(*hnsgreq), node);
536 tegra_dma_configure_for_next(tdc, hnsgreq);
537 }
538 }
539
540 static inline int get_current_xferred_count(struct tegra_dma_channel *tdc,
541 struct tegra_dma_sg_req *sg_req, unsigned long status)
542 {
543 return sg_req->req_len - (status & TEGRA_APBDMA_STATUS_COUNT_MASK) - 4;
544 }
545
546 static void tegra_dma_abort_all(struct tegra_dma_channel *tdc)
547 {
548 struct tegra_dma_sg_req *sgreq;
549 struct tegra_dma_desc *dma_desc;
550
551 while (!list_empty(&tdc->pending_sg_req)) {
552 sgreq = list_first_entry(&tdc->pending_sg_req,
553 typeof(*sgreq), node);
554 list_move_tail(&sgreq->node, &tdc->free_sg_req);
555 if (sgreq->last_sg) {
556 dma_desc = sgreq->dma_desc;
557 dma_desc->dma_status = DMA_ERROR;
558 list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
559
560 /* Add in cb list if it is not there. */
561 if (!dma_desc->cb_count)
562 list_add_tail(&dma_desc->cb_node,
563 &tdc->cb_desc);
564 dma_desc->cb_count++;
565 }
566 }
567 tdc->isr_handler = NULL;
568 }
569
570 static bool handle_continuous_head_request(struct tegra_dma_channel *tdc,
571 struct tegra_dma_sg_req *last_sg_req, bool to_terminate)
572 {
573 struct tegra_dma_sg_req *hsgreq = NULL;
574
575 if (list_empty(&tdc->pending_sg_req)) {
576 dev_err(tdc2dev(tdc), "Dma is running without req\n");
577 tegra_dma_stop(tdc);
578 return false;
579 }
580
581 /*
582 * Check that head req on list should be in flight.
583 * If it is not in flight then abort transfer as
584 * looping of transfer can not continue.
585 */
586 hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
587 if (!hsgreq->configured) {
588 tegra_dma_stop(tdc);
589 dev_err(tdc2dev(tdc), "Error in dma transfer, aborting dma\n");
590 tegra_dma_abort_all(tdc);
591 return false;
592 }
593
594 /* Configure next request */
595 if (!to_terminate)
596 tdc_configure_next_head_desc(tdc);
597 return true;
598 }
599
600 static void handle_once_dma_done(struct tegra_dma_channel *tdc,
601 bool to_terminate)
602 {
603 struct tegra_dma_sg_req *sgreq;
604 struct tegra_dma_desc *dma_desc;
605
606 tdc->busy = false;
607 sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
608 dma_desc = sgreq->dma_desc;
609 dma_desc->bytes_transferred += sgreq->req_len;
610
611 list_del(&sgreq->node);
612 if (sgreq->last_sg) {
613 dma_desc->dma_status = DMA_COMPLETE;
614 dma_cookie_complete(&dma_desc->txd);
615 if (!dma_desc->cb_count)
616 list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
617 dma_desc->cb_count++;
618 list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
619 }
620 list_add_tail(&sgreq->node, &tdc->free_sg_req);
621
622 /* Do not start DMA if it is going to be terminate */
623 if (to_terminate || list_empty(&tdc->pending_sg_req))
624 return;
625
626 tdc_start_head_req(tdc);
627 }
628
629 static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc,
630 bool to_terminate)
631 {
632 struct tegra_dma_sg_req *sgreq;
633 struct tegra_dma_desc *dma_desc;
634 bool st;
635
636 sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
637 dma_desc = sgreq->dma_desc;
638 dma_desc->bytes_transferred += sgreq->req_len;
639
640 /* Callback need to be call */
641 if (!dma_desc->cb_count)
642 list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
643 dma_desc->cb_count++;
644
645 /* If not last req then put at end of pending list */
646 if (!list_is_last(&sgreq->node, &tdc->pending_sg_req)) {
647 list_move_tail(&sgreq->node, &tdc->pending_sg_req);
648 sgreq->configured = false;
649 st = handle_continuous_head_request(tdc, sgreq, to_terminate);
650 if (!st)
651 dma_desc->dma_status = DMA_ERROR;
652 }
653 }
654
655 static void tegra_dma_tasklet(unsigned long data)
656 {
657 struct tegra_dma_channel *tdc = (struct tegra_dma_channel *)data;
658 struct dmaengine_desc_callback cb;
659 struct tegra_dma_desc *dma_desc;
660 unsigned long flags;
661 int cb_count;
662
663 spin_lock_irqsave(&tdc->lock, flags);
664 while (!list_empty(&tdc->cb_desc)) {
665 dma_desc = list_first_entry(&tdc->cb_desc,
666 typeof(*dma_desc), cb_node);
667 list_del(&dma_desc->cb_node);
668 dmaengine_desc_get_callback(&dma_desc->txd, &cb);
669 cb_count = dma_desc->cb_count;
670 dma_desc->cb_count = 0;
671 spin_unlock_irqrestore(&tdc->lock, flags);
672 while (cb_count--)
673 dmaengine_desc_callback_invoke(&cb, NULL);
674 spin_lock_irqsave(&tdc->lock, flags);
675 }
676 spin_unlock_irqrestore(&tdc->lock, flags);
677 }
678
679 static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
680 {
681 struct tegra_dma_channel *tdc = dev_id;
682 unsigned long status;
683 unsigned long flags;
684
685 spin_lock_irqsave(&tdc->lock, flags);
686
687 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
688 if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
689 tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status);
690 tdc->isr_handler(tdc, false);
691 tasklet_schedule(&tdc->tasklet);
692 spin_unlock_irqrestore(&tdc->lock, flags);
693 return IRQ_HANDLED;
694 }
695
696 spin_unlock_irqrestore(&tdc->lock, flags);
697 dev_info(tdc2dev(tdc),
698 "Interrupt already served status 0x%08lx\n", status);
699 return IRQ_NONE;
700 }
701
702 static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *txd)
703 {
704 struct tegra_dma_desc *dma_desc = txd_to_tegra_dma_desc(txd);
705 struct tegra_dma_channel *tdc = to_tegra_dma_chan(txd->chan);
706 unsigned long flags;
707 dma_cookie_t cookie;
708
709 spin_lock_irqsave(&tdc->lock, flags);
710 dma_desc->dma_status = DMA_IN_PROGRESS;
711 cookie = dma_cookie_assign(&dma_desc->txd);
712 list_splice_tail_init(&dma_desc->tx_list, &tdc->pending_sg_req);
713 spin_unlock_irqrestore(&tdc->lock, flags);
714 return cookie;
715 }
716
717 static void tegra_dma_issue_pending(struct dma_chan *dc)
718 {
719 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
720 unsigned long flags;
721
722 spin_lock_irqsave(&tdc->lock, flags);
723 if (list_empty(&tdc->pending_sg_req)) {
724 dev_err(tdc2dev(tdc), "No DMA request\n");
725 goto end;
726 }
727 if (!tdc->busy) {
728 tdc_start_head_req(tdc);
729
730 /* Continuous single mode: Configure next req */
731 if (tdc->cyclic) {
732 /*
733 * Wait for 1 burst time for configure DMA for
734 * next transfer.
735 */
736 udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
737 tdc_configure_next_head_desc(tdc);
738 }
739 }
740 end:
741 spin_unlock_irqrestore(&tdc->lock, flags);
742 }
743
744 static int tegra_dma_terminate_all(struct dma_chan *dc)
745 {
746 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
747 struct tegra_dma_sg_req *sgreq;
748 struct tegra_dma_desc *dma_desc;
749 unsigned long flags;
750 unsigned long status;
751 unsigned long wcount;
752 bool was_busy;
753
754 spin_lock_irqsave(&tdc->lock, flags);
755 if (list_empty(&tdc->pending_sg_req)) {
756 spin_unlock_irqrestore(&tdc->lock, flags);
757 return 0;
758 }
759
760 if (!tdc->busy)
761 goto skip_dma_stop;
762
763 /* Pause DMA before checking the queue status */
764 tegra_dma_pause(tdc, true);
765
766 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
767 if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
768 dev_dbg(tdc2dev(tdc), "%s():handling isr\n", __func__);
769 tdc->isr_handler(tdc, true);
770 status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
771 }
772 if (tdc->tdma->chip_data->support_separate_wcount_reg)
773 wcount = tdc_read(tdc, TEGRA_APBDMA_CHAN_WORD_TRANSFER);
774 else
775 wcount = status;
776
777 was_busy = tdc->busy;
778 tegra_dma_stop(tdc);
779
780 if (!list_empty(&tdc->pending_sg_req) && was_busy) {
781 sgreq = list_first_entry(&tdc->pending_sg_req,
782 typeof(*sgreq), node);
783 sgreq->dma_desc->bytes_transferred +=
784 get_current_xferred_count(tdc, sgreq, wcount);
785 }
786 tegra_dma_resume(tdc);
787
788 skip_dma_stop:
789 tegra_dma_abort_all(tdc);
790
791 while (!list_empty(&tdc->cb_desc)) {
792 dma_desc = list_first_entry(&tdc->cb_desc,
793 typeof(*dma_desc), cb_node);
794 list_del(&dma_desc->cb_node);
795 dma_desc->cb_count = 0;
796 }
797 spin_unlock_irqrestore(&tdc->lock, flags);
798 return 0;
799 }
800
801 static enum dma_status tegra_dma_tx_status(struct dma_chan *dc,
802 dma_cookie_t cookie, struct dma_tx_state *txstate)
803 {
804 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
805 struct tegra_dma_desc *dma_desc;
806 struct tegra_dma_sg_req *sg_req;
807 enum dma_status ret;
808 unsigned long flags;
809 unsigned int residual;
810
811 ret = dma_cookie_status(dc, cookie, txstate);
812 if (ret == DMA_COMPLETE)
813 return ret;
814
815 spin_lock_irqsave(&tdc->lock, flags);
816
817 /* Check on wait_ack desc status */
818 list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
819 if (dma_desc->txd.cookie == cookie) {
820 ret = dma_desc->dma_status;
821 goto found;
822 }
823 }
824
825 /* Check in pending list */
826 list_for_each_entry(sg_req, &tdc->pending_sg_req, node) {
827 dma_desc = sg_req->dma_desc;
828 if (dma_desc->txd.cookie == cookie) {
829 ret = dma_desc->dma_status;
830 goto found;
831 }
832 }
833
834 dev_dbg(tdc2dev(tdc), "cookie %d not found\n", cookie);
835 dma_desc = NULL;
836
837 found:
838 if (dma_desc && txstate) {
839 residual = dma_desc->bytes_requested -
840 (dma_desc->bytes_transferred %
841 dma_desc->bytes_requested);
842 dma_set_residue(txstate, residual);
843 }
844
845 spin_unlock_irqrestore(&tdc->lock, flags);
846 return ret;
847 }
848
849 static inline int get_bus_width(struct tegra_dma_channel *tdc,
850 enum dma_slave_buswidth slave_bw)
851 {
852 switch (slave_bw) {
853 case DMA_SLAVE_BUSWIDTH_1_BYTE:
854 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8;
855 case DMA_SLAVE_BUSWIDTH_2_BYTES:
856 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16;
857 case DMA_SLAVE_BUSWIDTH_4_BYTES:
858 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32;
859 case DMA_SLAVE_BUSWIDTH_8_BYTES:
860 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64;
861 default:
862 dev_warn(tdc2dev(tdc),
863 "slave bw is not supported, using 32bits\n");
864 return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32;
865 }
866 }
867
868 static inline int get_burst_size(struct tegra_dma_channel *tdc,
869 u32 burst_size, enum dma_slave_buswidth slave_bw, int len)
870 {
871 int burst_byte;
872 int burst_ahb_width;
873
874 /*
875 * burst_size from client is in terms of the bus_width.
876 * convert them into AHB memory width which is 4 byte.
877 */
878 burst_byte = burst_size * slave_bw;
879 burst_ahb_width = burst_byte / 4;
880
881 /* If burst size is 0 then calculate the burst size based on length */
882 if (!burst_ahb_width) {
883 if (len & 0xF)
884 return TEGRA_APBDMA_AHBSEQ_BURST_1;
885 else if ((len >> 4) & 0x1)
886 return TEGRA_APBDMA_AHBSEQ_BURST_4;
887 else
888 return TEGRA_APBDMA_AHBSEQ_BURST_8;
889 }
890 if (burst_ahb_width < 4)
891 return TEGRA_APBDMA_AHBSEQ_BURST_1;
892 else if (burst_ahb_width < 8)
893 return TEGRA_APBDMA_AHBSEQ_BURST_4;
894 else
895 return TEGRA_APBDMA_AHBSEQ_BURST_8;
896 }
897
898 static int get_transfer_param(struct tegra_dma_channel *tdc,
899 enum dma_transfer_direction direction, unsigned long *apb_addr,
900 unsigned long *apb_seq, unsigned long *csr, unsigned int *burst_size,
901 enum dma_slave_buswidth *slave_bw)
902 {
903 switch (direction) {
904 case DMA_MEM_TO_DEV:
905 *apb_addr = tdc->dma_sconfig.dst_addr;
906 *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.dst_addr_width);
907 *burst_size = tdc->dma_sconfig.dst_maxburst;
908 *slave_bw = tdc->dma_sconfig.dst_addr_width;
909 *csr = TEGRA_APBDMA_CSR_DIR;
910 return 0;
911
912 case DMA_DEV_TO_MEM:
913 *apb_addr = tdc->dma_sconfig.src_addr;
914 *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.src_addr_width);
915 *burst_size = tdc->dma_sconfig.src_maxburst;
916 *slave_bw = tdc->dma_sconfig.src_addr_width;
917 *csr = 0;
918 return 0;
919
920 default:
921 dev_err(tdc2dev(tdc), "Dma direction is not supported\n");
922 return -EINVAL;
923 }
924 return -EINVAL;
925 }
926
927 static void tegra_dma_prep_wcount(struct tegra_dma_channel *tdc,
928 struct tegra_dma_channel_regs *ch_regs, u32 len)
929 {
930 u32 len_field = (len - 4) & 0xFFFC;
931
932 if (tdc->tdma->chip_data->support_separate_wcount_reg)
933 ch_regs->wcount = len_field;
934 else
935 ch_regs->csr |= len_field;
936 }
937
938 static struct dma_async_tx_descriptor *tegra_dma_prep_slave_sg(
939 struct dma_chan *dc, struct scatterlist *sgl, unsigned int sg_len,
940 enum dma_transfer_direction direction, unsigned long flags,
941 void *context)
942 {
943 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
944 struct tegra_dma_desc *dma_desc;
945 unsigned int i;
946 struct scatterlist *sg;
947 unsigned long csr, ahb_seq, apb_ptr, apb_seq;
948 struct list_head req_list;
949 struct tegra_dma_sg_req *sg_req = NULL;
950 u32 burst_size;
951 enum dma_slave_buswidth slave_bw;
952
953 if (!tdc->config_init) {
954 dev_err(tdc2dev(tdc), "dma channel is not configured\n");
955 return NULL;
956 }
957 if (sg_len < 1) {
958 dev_err(tdc2dev(tdc), "Invalid segment length %d\n", sg_len);
959 return NULL;
960 }
961
962 if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr,
963 &burst_size, &slave_bw) < 0)
964 return NULL;
965
966 INIT_LIST_HEAD(&req_list);
967
968 ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB;
969 ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE <<
970 TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT;
971 ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32;
972
973 csr |= TEGRA_APBDMA_CSR_ONCE | TEGRA_APBDMA_CSR_FLOW;
974 csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
975 if (flags & DMA_PREP_INTERRUPT)
976 csr |= TEGRA_APBDMA_CSR_IE_EOC;
977
978 apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1;
979
980 dma_desc = tegra_dma_desc_get(tdc);
981 if (!dma_desc) {
982 dev_err(tdc2dev(tdc), "Dma descriptors not available\n");
983 return NULL;
984 }
985 INIT_LIST_HEAD(&dma_desc->tx_list);
986 INIT_LIST_HEAD(&dma_desc->cb_node);
987 dma_desc->cb_count = 0;
988 dma_desc->bytes_requested = 0;
989 dma_desc->bytes_transferred = 0;
990 dma_desc->dma_status = DMA_IN_PROGRESS;
991
992 /* Make transfer requests */
993 for_each_sg(sgl, sg, sg_len, i) {
994 u32 len, mem;
995
996 mem = sg_dma_address(sg);
997 len = sg_dma_len(sg);
998
999 if ((len & 3) || (mem & 3) ||
1000 (len > tdc->tdma->chip_data->max_dma_count)) {
1001 dev_err(tdc2dev(tdc),
1002 "Dma length/memory address is not supported\n");
1003 tegra_dma_desc_put(tdc, dma_desc);
1004 return NULL;
1005 }
1006
1007 sg_req = tegra_dma_sg_req_get(tdc);
1008 if (!sg_req) {
1009 dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
1010 tegra_dma_desc_put(tdc, dma_desc);
1011 return NULL;
1012 }
1013
1014 ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
1015 dma_desc->bytes_requested += len;
1016
1017 sg_req->ch_regs.apb_ptr = apb_ptr;
1018 sg_req->ch_regs.ahb_ptr = mem;
1019 sg_req->ch_regs.csr = csr;
1020 tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len);
1021 sg_req->ch_regs.apb_seq = apb_seq;
1022 sg_req->ch_regs.ahb_seq = ahb_seq;
1023 sg_req->configured = false;
1024 sg_req->last_sg = false;
1025 sg_req->dma_desc = dma_desc;
1026 sg_req->req_len = len;
1027
1028 list_add_tail(&sg_req->node, &dma_desc->tx_list);
1029 }
1030 sg_req->last_sg = true;
1031 if (flags & DMA_CTRL_ACK)
1032 dma_desc->txd.flags = DMA_CTRL_ACK;
1033
1034 /*
1035 * Make sure that mode should not be conflicting with currently
1036 * configured mode.
1037 */
1038 if (!tdc->isr_handler) {
1039 tdc->isr_handler = handle_once_dma_done;
1040 tdc->cyclic = false;
1041 } else {
1042 if (tdc->cyclic) {
1043 dev_err(tdc2dev(tdc), "DMA configured in cyclic mode\n");
1044 tegra_dma_desc_put(tdc, dma_desc);
1045 return NULL;
1046 }
1047 }
1048
1049 return &dma_desc->txd;
1050 }
1051
1052 static struct dma_async_tx_descriptor *tegra_dma_prep_dma_cyclic(
1053 struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len,
1054 size_t period_len, enum dma_transfer_direction direction,
1055 unsigned long flags)
1056 {
1057 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1058 struct tegra_dma_desc *dma_desc = NULL;
1059 struct tegra_dma_sg_req *sg_req = NULL;
1060 unsigned long csr, ahb_seq, apb_ptr, apb_seq;
1061 int len;
1062 size_t remain_len;
1063 dma_addr_t mem = buf_addr;
1064 u32 burst_size;
1065 enum dma_slave_buswidth slave_bw;
1066
1067 if (!buf_len || !period_len) {
1068 dev_err(tdc2dev(tdc), "Invalid buffer/period len\n");
1069 return NULL;
1070 }
1071
1072 if (!tdc->config_init) {
1073 dev_err(tdc2dev(tdc), "DMA slave is not configured\n");
1074 return NULL;
1075 }
1076
1077 /*
1078 * We allow to take more number of requests till DMA is
1079 * not started. The driver will loop over all requests.
1080 * Once DMA is started then new requests can be queued only after
1081 * terminating the DMA.
1082 */
1083 if (tdc->busy) {
1084 dev_err(tdc2dev(tdc), "Request not allowed when dma running\n");
1085 return NULL;
1086 }
1087
1088 /*
1089 * We only support cycle transfer when buf_len is multiple of
1090 * period_len.
1091 */
1092 if (buf_len % period_len) {
1093 dev_err(tdc2dev(tdc), "buf_len is not multiple of period_len\n");
1094 return NULL;
1095 }
1096
1097 len = period_len;
1098 if ((len & 3) || (buf_addr & 3) ||
1099 (len > tdc->tdma->chip_data->max_dma_count)) {
1100 dev_err(tdc2dev(tdc), "Req len/mem address is not correct\n");
1101 return NULL;
1102 }
1103
1104 if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr,
1105 &burst_size, &slave_bw) < 0)
1106 return NULL;
1107
1108 ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB;
1109 ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE <<
1110 TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT;
1111 ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32;
1112
1113 csr |= TEGRA_APBDMA_CSR_FLOW;
1114 if (flags & DMA_PREP_INTERRUPT)
1115 csr |= TEGRA_APBDMA_CSR_IE_EOC;
1116 csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
1117
1118 apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1;
1119
1120 dma_desc = tegra_dma_desc_get(tdc);
1121 if (!dma_desc) {
1122 dev_err(tdc2dev(tdc), "not enough descriptors available\n");
1123 return NULL;
1124 }
1125
1126 INIT_LIST_HEAD(&dma_desc->tx_list);
1127 INIT_LIST_HEAD(&dma_desc->cb_node);
1128 dma_desc->cb_count = 0;
1129
1130 dma_desc->bytes_transferred = 0;
1131 dma_desc->bytes_requested = buf_len;
1132 remain_len = buf_len;
1133
1134 /* Split transfer equal to period size */
1135 while (remain_len) {
1136 sg_req = tegra_dma_sg_req_get(tdc);
1137 if (!sg_req) {
1138 dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
1139 tegra_dma_desc_put(tdc, dma_desc);
1140 return NULL;
1141 }
1142
1143 ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
1144 sg_req->ch_regs.apb_ptr = apb_ptr;
1145 sg_req->ch_regs.ahb_ptr = mem;
1146 sg_req->ch_regs.csr = csr;
1147 tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len);
1148 sg_req->ch_regs.apb_seq = apb_seq;
1149 sg_req->ch_regs.ahb_seq = ahb_seq;
1150 sg_req->configured = false;
1151 sg_req->last_sg = false;
1152 sg_req->dma_desc = dma_desc;
1153 sg_req->req_len = len;
1154
1155 list_add_tail(&sg_req->node, &dma_desc->tx_list);
1156 remain_len -= len;
1157 mem += len;
1158 }
1159 sg_req->last_sg = true;
1160 if (flags & DMA_CTRL_ACK)
1161 dma_desc->txd.flags = DMA_CTRL_ACK;
1162
1163 /*
1164 * Make sure that mode should not be conflicting with currently
1165 * configured mode.
1166 */
1167 if (!tdc->isr_handler) {
1168 tdc->isr_handler = handle_cont_sngl_cycle_dma_done;
1169 tdc->cyclic = true;
1170 } else {
1171 if (!tdc->cyclic) {
1172 dev_err(tdc2dev(tdc), "DMA configuration conflict\n");
1173 tegra_dma_desc_put(tdc, dma_desc);
1174 return NULL;
1175 }
1176 }
1177
1178 return &dma_desc->txd;
1179 }
1180
1181 static int tegra_dma_alloc_chan_resources(struct dma_chan *dc)
1182 {
1183 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1184 struct tegra_dma *tdma = tdc->tdma;
1185 int ret;
1186
1187 dma_cookie_init(&tdc->dma_chan);
1188 tdc->config_init = false;
1189
1190 ret = pm_runtime_get_sync(tdma->dev);
1191 if (ret < 0)
1192 return ret;
1193
1194 return 0;
1195 }
1196
1197 static void tegra_dma_free_chan_resources(struct dma_chan *dc)
1198 {
1199 struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1200 struct tegra_dma *tdma = tdc->tdma;
1201 struct tegra_dma_desc *dma_desc;
1202 struct tegra_dma_sg_req *sg_req;
1203 struct list_head dma_desc_list;
1204 struct list_head sg_req_list;
1205 unsigned long flags;
1206
1207 INIT_LIST_HEAD(&dma_desc_list);
1208 INIT_LIST_HEAD(&sg_req_list);
1209
1210 dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id);
1211
1212 if (tdc->busy)
1213 tegra_dma_terminate_all(dc);
1214
1215 spin_lock_irqsave(&tdc->lock, flags);
1216 list_splice_init(&tdc->pending_sg_req, &sg_req_list);
1217 list_splice_init(&tdc->free_sg_req, &sg_req_list);
1218 list_splice_init(&tdc->free_dma_desc, &dma_desc_list);
1219 INIT_LIST_HEAD(&tdc->cb_desc);
1220 tdc->config_init = false;
1221 tdc->isr_handler = NULL;
1222 spin_unlock_irqrestore(&tdc->lock, flags);
1223
1224 while (!list_empty(&dma_desc_list)) {
1225 dma_desc = list_first_entry(&dma_desc_list,
1226 typeof(*dma_desc), node);
1227 list_del(&dma_desc->node);
1228 kfree(dma_desc);
1229 }
1230
1231 while (!list_empty(&sg_req_list)) {
1232 sg_req = list_first_entry(&sg_req_list, typeof(*sg_req), node);
1233 list_del(&sg_req->node);
1234 kfree(sg_req);
1235 }
1236 pm_runtime_put(tdma->dev);
1237
1238 tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID;
1239 }
1240
1241 static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
1242 struct of_dma *ofdma)
1243 {
1244 struct tegra_dma *tdma = ofdma->of_dma_data;
1245 struct dma_chan *chan;
1246 struct tegra_dma_channel *tdc;
1247
1248 if (dma_spec->args[0] > TEGRA_APBDMA_CSR_REQ_SEL_MASK) {
1249 dev_err(tdma->dev, "Invalid slave id: %d\n", dma_spec->args[0]);
1250 return NULL;
1251 }
1252
1253 chan = dma_get_any_slave_channel(&tdma->dma_dev);
1254 if (!chan)
1255 return NULL;
1256
1257 tdc = to_tegra_dma_chan(chan);
1258 tdc->slave_id = dma_spec->args[0];
1259
1260 return chan;
1261 }
1262
1263 /* Tegra20 specific DMA controller information */
1264 static const struct tegra_dma_chip_data tegra20_dma_chip_data = {
1265 .nr_channels = 16,
1266 .channel_reg_size = 0x20,
1267 .max_dma_count = 1024UL * 64,
1268 .support_channel_pause = false,
1269 .support_separate_wcount_reg = false,
1270 };
1271
1272 /* Tegra30 specific DMA controller information */
1273 static const struct tegra_dma_chip_data tegra30_dma_chip_data = {
1274 .nr_channels = 32,
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 /* Tegra114 specific DMA controller information */
1282 static const struct tegra_dma_chip_data tegra114_dma_chip_data = {
1283 .nr_channels = 32,
1284 .channel_reg_size = 0x20,
1285 .max_dma_count = 1024UL * 64,
1286 .support_channel_pause = true,
1287 .support_separate_wcount_reg = false,
1288 };
1289
1290 /* Tegra148 specific DMA controller information */
1291 static const struct tegra_dma_chip_data tegra148_dma_chip_data = {
1292 .nr_channels = 32,
1293 .channel_reg_size = 0x40,
1294 .max_dma_count = 1024UL * 64,
1295 .support_channel_pause = true,
1296 .support_separate_wcount_reg = true,
1297 };
1298
1299 static int tegra_dma_probe(struct platform_device *pdev)
1300 {
1301 struct resource *res;
1302 struct tegra_dma *tdma;
1303 int ret;
1304 int i;
1305 const struct tegra_dma_chip_data *cdata;
1306
1307 cdata = of_device_get_match_data(&pdev->dev);
1308 if (!cdata) {
1309 dev_err(&pdev->dev, "Error: No device match data found\n");
1310 return -ENODEV;
1311 }
1312
1313 tdma = devm_kzalloc(&pdev->dev, sizeof(*tdma) + cdata->nr_channels *
1314 sizeof(struct tegra_dma_channel), GFP_KERNEL);
1315 if (!tdma)
1316 return -ENOMEM;
1317
1318 tdma->dev = &pdev->dev;
1319 tdma->chip_data = cdata;
1320 platform_set_drvdata(pdev, tdma);
1321
1322 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1323 tdma->base_addr = devm_ioremap_resource(&pdev->dev, res);
1324 if (IS_ERR(tdma->base_addr))
1325 return PTR_ERR(tdma->base_addr);
1326
1327 tdma->dma_clk = devm_clk_get(&pdev->dev, NULL);
1328 if (IS_ERR(tdma->dma_clk)) {
1329 dev_err(&pdev->dev, "Error: Missing controller clock\n");
1330 return PTR_ERR(tdma->dma_clk);
1331 }
1332
1333 tdma->rst = devm_reset_control_get(&pdev->dev, "dma");
1334 if (IS_ERR(tdma->rst)) {
1335 dev_err(&pdev->dev, "Error: Missing reset\n");
1336 return PTR_ERR(tdma->rst);
1337 }
1338
1339 spin_lock_init(&tdma->global_lock);
1340
1341 pm_runtime_enable(&pdev->dev);
1342 if (!pm_runtime_enabled(&pdev->dev))
1343 ret = tegra_dma_runtime_resume(&pdev->dev);
1344 else
1345 ret = pm_runtime_get_sync(&pdev->dev);
1346
1347 if (ret < 0) {
1348 pm_runtime_disable(&pdev->dev);
1349 return ret;
1350 }
1351
1352 /* Reset DMA controller */
1353 reset_control_assert(tdma->rst);
1354 udelay(2);
1355 reset_control_deassert(tdma->rst);
1356
1357 /* Enable global DMA registers */
1358 tdma_write(tdma, TEGRA_APBDMA_GENERAL, TEGRA_APBDMA_GENERAL_ENABLE);
1359 tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0);
1360 tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul);
1361
1362 pm_runtime_put(&pdev->dev);
1363
1364 INIT_LIST_HEAD(&tdma->dma_dev.channels);
1365 for (i = 0; i < cdata->nr_channels; i++) {
1366 struct tegra_dma_channel *tdc = &tdma->channels[i];
1367
1368 tdc->chan_addr = tdma->base_addr +
1369 TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET +
1370 (i * cdata->channel_reg_size);
1371
1372 res = platform_get_resource(pdev, IORESOURCE_IRQ, i);
1373 if (!res) {
1374 ret = -EINVAL;
1375 dev_err(&pdev->dev, "No irq resource for chan %d\n", i);
1376 goto err_irq;
1377 }
1378 tdc->irq = res->start;
1379 snprintf(tdc->name, sizeof(tdc->name), "apbdma.%d", i);
1380 ret = request_irq(tdc->irq, tegra_dma_isr, 0, tdc->name, tdc);
1381 if (ret) {
1382 dev_err(&pdev->dev,
1383 "request_irq failed with err %d channel %d\n",
1384 ret, i);
1385 goto err_irq;
1386 }
1387
1388 tdc->dma_chan.device = &tdma->dma_dev;
1389 dma_cookie_init(&tdc->dma_chan);
1390 list_add_tail(&tdc->dma_chan.device_node,
1391 &tdma->dma_dev.channels);
1392 tdc->tdma = tdma;
1393 tdc->id = i;
1394 tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID;
1395
1396 tasklet_init(&tdc->tasklet, tegra_dma_tasklet,
1397 (unsigned long)tdc);
1398 spin_lock_init(&tdc->lock);
1399
1400 INIT_LIST_HEAD(&tdc->pending_sg_req);
1401 INIT_LIST_HEAD(&tdc->free_sg_req);
1402 INIT_LIST_HEAD(&tdc->free_dma_desc);
1403 INIT_LIST_HEAD(&tdc->cb_desc);
1404 }
1405
1406 dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask);
1407 dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask);
1408 dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask);
1409
1410 tdma->global_pause_count = 0;
1411 tdma->dma_dev.dev = &pdev->dev;
1412 tdma->dma_dev.device_alloc_chan_resources =
1413 tegra_dma_alloc_chan_resources;
1414 tdma->dma_dev.device_free_chan_resources =
1415 tegra_dma_free_chan_resources;
1416 tdma->dma_dev.device_prep_slave_sg = tegra_dma_prep_slave_sg;
1417 tdma->dma_dev.device_prep_dma_cyclic = tegra_dma_prep_dma_cyclic;
1418 tdma->dma_dev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1419 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1420 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1421 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
1422 tdma->dma_dev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1423 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1424 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1425 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
1426 tdma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1427 /*
1428 * XXX The hardware appears to support
1429 * DMA_RESIDUE_GRANULARITY_BURST-level reporting, but it's
1430 * only used by this driver during tegra_dma_terminate_all()
1431 */
1432 tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
1433 tdma->dma_dev.device_config = tegra_dma_slave_config;
1434 tdma->dma_dev.device_terminate_all = tegra_dma_terminate_all;
1435 tdma->dma_dev.device_tx_status = tegra_dma_tx_status;
1436 tdma->dma_dev.device_issue_pending = tegra_dma_issue_pending;
1437
1438 ret = dma_async_device_register(&tdma->dma_dev);
1439 if (ret < 0) {
1440 dev_err(&pdev->dev,
1441 "Tegra20 APB DMA driver registration failed %d\n", ret);
1442 goto err_irq;
1443 }
1444
1445 ret = of_dma_controller_register(pdev->dev.of_node,
1446 tegra_dma_of_xlate, tdma);
1447 if (ret < 0) {
1448 dev_err(&pdev->dev,
1449 "Tegra20 APB DMA OF registration failed %d\n", ret);
1450 goto err_unregister_dma_dev;
1451 }
1452
1453 dev_info(&pdev->dev, "Tegra20 APB DMA driver register %d channels\n",
1454 cdata->nr_channels);
1455 return 0;
1456
1457 err_unregister_dma_dev:
1458 dma_async_device_unregister(&tdma->dma_dev);
1459 err_irq:
1460 while (--i >= 0) {
1461 struct tegra_dma_channel *tdc = &tdma->channels[i];
1462
1463 free_irq(tdc->irq, tdc);
1464 tasklet_kill(&tdc->tasklet);
1465 }
1466
1467 pm_runtime_disable(&pdev->dev);
1468 if (!pm_runtime_status_suspended(&pdev->dev))
1469 tegra_dma_runtime_suspend(&pdev->dev);
1470 return ret;
1471 }
1472
1473 static int tegra_dma_remove(struct platform_device *pdev)
1474 {
1475 struct tegra_dma *tdma = platform_get_drvdata(pdev);
1476 int i;
1477 struct tegra_dma_channel *tdc;
1478
1479 dma_async_device_unregister(&tdma->dma_dev);
1480
1481 for (i = 0; i < tdma->chip_data->nr_channels; ++i) {
1482 tdc = &tdma->channels[i];
1483 free_irq(tdc->irq, tdc);
1484 tasklet_kill(&tdc->tasklet);
1485 }
1486
1487 pm_runtime_disable(&pdev->dev);
1488 if (!pm_runtime_status_suspended(&pdev->dev))
1489 tegra_dma_runtime_suspend(&pdev->dev);
1490
1491 return 0;
1492 }
1493
1494 static int tegra_dma_runtime_suspend(struct device *dev)
1495 {
1496 struct tegra_dma *tdma = dev_get_drvdata(dev);
1497
1498 clk_disable_unprepare(tdma->dma_clk);
1499 return 0;
1500 }
1501
1502 static int tegra_dma_runtime_resume(struct device *dev)
1503 {
1504 struct tegra_dma *tdma = dev_get_drvdata(dev);
1505 int ret;
1506
1507 ret = clk_prepare_enable(tdma->dma_clk);
1508 if (ret < 0) {
1509 dev_err(dev, "clk_enable failed: %d\n", ret);
1510 return ret;
1511 }
1512 return 0;
1513 }
1514
1515 #ifdef CONFIG_PM_SLEEP
1516 static int tegra_dma_pm_suspend(struct device *dev)
1517 {
1518 struct tegra_dma *tdma = dev_get_drvdata(dev);
1519 int i;
1520 int ret;
1521
1522 /* Enable clock before accessing register */
1523 ret = pm_runtime_get_sync(dev);
1524 if (ret < 0)
1525 return ret;
1526
1527 tdma->reg_gen = tdma_read(tdma, TEGRA_APBDMA_GENERAL);
1528 for (i = 0; i < tdma->chip_data->nr_channels; i++) {
1529 struct tegra_dma_channel *tdc = &tdma->channels[i];
1530 struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg;
1531
1532 /* Only save the state of DMA channels that are in use */
1533 if (!tdc->config_init)
1534 continue;
1535
1536 ch_reg->csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR);
1537 ch_reg->ahb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBPTR);
1538 ch_reg->apb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBPTR);
1539 ch_reg->ahb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBSEQ);
1540 ch_reg->apb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBSEQ);
1541 if (tdma->chip_data->support_separate_wcount_reg)
1542 ch_reg->wcount = tdc_read(tdc,
1543 TEGRA_APBDMA_CHAN_WCOUNT);
1544 }
1545
1546 /* Disable clock */
1547 pm_runtime_put(dev);
1548 return 0;
1549 }
1550
1551 static int tegra_dma_pm_resume(struct device *dev)
1552 {
1553 struct tegra_dma *tdma = dev_get_drvdata(dev);
1554 int i;
1555 int ret;
1556
1557 /* Enable clock before accessing register */
1558 ret = pm_runtime_get_sync(dev);
1559 if (ret < 0)
1560 return ret;
1561
1562 tdma_write(tdma, TEGRA_APBDMA_GENERAL, tdma->reg_gen);
1563 tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0);
1564 tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul);
1565
1566 for (i = 0; i < tdma->chip_data->nr_channels; i++) {
1567 struct tegra_dma_channel *tdc = &tdma->channels[i];
1568 struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg;
1569
1570 /* Only restore the state of DMA channels that are in use */
1571 if (!tdc->config_init)
1572 continue;
1573
1574 if (tdma->chip_data->support_separate_wcount_reg)
1575 tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT,
1576 ch_reg->wcount);
1577 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_reg->apb_seq);
1578 tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_reg->apb_ptr);
1579 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_reg->ahb_seq);
1580 tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_reg->ahb_ptr);
1581 tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
1582 (ch_reg->csr & ~TEGRA_APBDMA_CSR_ENB));
1583 }
1584
1585 /* Disable clock */
1586 pm_runtime_put(dev);
1587 return 0;
1588 }
1589 #endif
1590
1591 static const struct dev_pm_ops tegra_dma_dev_pm_ops = {
1592 SET_RUNTIME_PM_OPS(tegra_dma_runtime_suspend, tegra_dma_runtime_resume,
1593 NULL)
1594 SET_SYSTEM_SLEEP_PM_OPS(tegra_dma_pm_suspend, tegra_dma_pm_resume)
1595 };
1596
1597 static const struct of_device_id tegra_dma_of_match[] = {
1598 {
1599 .compatible = "nvidia,tegra148-apbdma",
1600 .data = &tegra148_dma_chip_data,
1601 }, {
1602 .compatible = "nvidia,tegra114-apbdma",
1603 .data = &tegra114_dma_chip_data,
1604 }, {
1605 .compatible = "nvidia,tegra30-apbdma",
1606 .data = &tegra30_dma_chip_data,
1607 }, {
1608 .compatible = "nvidia,tegra20-apbdma",
1609 .data = &tegra20_dma_chip_data,
1610 }, {
1611 },
1612 };
1613 MODULE_DEVICE_TABLE(of, tegra_dma_of_match);
1614
1615 static struct platform_driver tegra_dmac_driver = {
1616 .driver = {
1617 .name = "tegra-apbdma",
1618 .pm = &tegra_dma_dev_pm_ops,
1619 .of_match_table = tegra_dma_of_match,
1620 },
1621 .probe = tegra_dma_probe,
1622 .remove = tegra_dma_remove,
1623 };
1624
1625 module_platform_driver(tegra_dmac_driver);
1626
1627 MODULE_ALIAS("platform:tegra20-apbdma");
1628 MODULE_DESCRIPTION("NVIDIA Tegra APB DMA Controller driver");
1629 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
1630 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support