1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/arch/arm/plat-omap/dma.c
4 *
5 * Copyright (C) 2003 - 2008 Nokia Corporation
6 * Author: Juha Yrjölä <juha.yrjola@nokia.com>
7 * DMA channel linking for 1610 by Samuel Ortiz <samuel.ortiz@nokia.com>
8 * Graphics DMA and LCD DMA graphics tranformations
9 * by Imre Deak <imre.deak@nokia.com>
10 * OMAP2/3 support Copyright (C) 2004-2007 Texas Instruments, Inc.
11 * Merged to support both OMAP1 and OMAP2 by Tony Lindgren <tony@atomide.com>
12 * Some functions based on earlier dma-omap.c Copyright (C) 2001 RidgeRun, Inc.
13 *
14 * Copyright (C) 2009 Texas Instruments
15 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
16 *
17 * Support functions for the OMAP internal DMA channels.
18 *
19 * Copyright (C) 2010 Texas Instruments Incorporated - https://www.ti.com/
20 * Converted DMA library into DMA platform driver.
21 * - G, Manjunath Kondaiah <manjugk@ti.com>
22 */
23
24 #include <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/sched.h>
27 #include <linux/spinlock.h>
28 #include <linux/errno.h>
29 #include <linux/interrupt.h>
30 #include <linux/irq.h>
31 #include <linux/io.h>
32 #include <linux/slab.h>
33 #include <linux/delay.h>
34
35 #include <linux/omap-dma.h>
36
37 #include <linux/soc/ti/omap1-io.h>
38 #include <linux/soc/ti/omap1-soc.h>
39
40 #include "tc.h"
41
42 /*
43 * MAX_LOGICAL_DMA_CH_COUNT: the maximum number of logical DMA
44 * channels that an instance of the SDMA IP block can support. Used
45 * to size arrays. (The actual maximum on a particular SoC may be less
46 * than this -- for example, OMAP1 SDMA instances only support 17 logical
47 * DMA channels.)
48 */
49 #define MAX_LOGICAL_DMA_CH_COUNT 32
50
51 #undef DEBUG
52
53 #define OMAP_DMA_ACTIVE 0x01
54
55 #define OMAP_FUNC_MUX_ARM_BASE (0xfffe1000 + 0xec)
56
57 static struct omap_system_dma_plat_info *p;
58 static struct omap_dma_dev_attr *d;
59 static int enable_1510_mode;
60 static u32 errata;
61
62 struct dma_link_info {
63 int *linked_dmach_q;
64 int no_of_lchs_linked;
65
66 int q_count;
67 int q_tail;
68 int q_head;
69
70 int chain_state;
71 int chain_mode;
72
73 };
74
75 static int dma_lch_count;
76 static int dma_chan_count;
77 static int omap_dma_reserve_channels;
78
79 static DEFINE_SPINLOCK(dma_chan_lock);
80 static struct omap_dma_lch *dma_chan;
81
omap_disable_channel_irq(int lch)82 static inline void omap_disable_channel_irq(int lch)
83 {
84 /* disable channel interrupts */
85 p->dma_write(0, CICR, lch);
86 /* Clear CSR */
87 p->dma_read(CSR, lch);
88 }
89
set_gdma_dev(int req,int dev)90 static inline void set_gdma_dev(int req, int dev)
91 {
92 u32 reg = OMAP_FUNC_MUX_ARM_BASE + ((req - 1) / 5) * 4;
93 int shift = ((req - 1) % 5) * 6;
94 u32 l;
95
96 l = omap_readl(reg);
97 l &= ~(0x3f << shift);
98 l |= (dev - 1) << shift;
99 omap_writel(l, reg);
100 }
101
102 #if IS_ENABLED(CONFIG_FB_OMAP)
omap_set_dma_priority(int lch,int dst_port,int priority)103 void omap_set_dma_priority(int lch, int dst_port, int priority)
104 {
105 unsigned long reg;
106 u32 l;
107
108 if (dma_omap1()) {
109 switch (dst_port) {
110 case OMAP_DMA_PORT_OCP_T1: /* FFFECC00 */
111 reg = OMAP_TC_OCPT1_PRIOR;
112 break;
113 case OMAP_DMA_PORT_OCP_T2: /* FFFECCD0 */
114 reg = OMAP_TC_OCPT2_PRIOR;
115 break;
116 case OMAP_DMA_PORT_EMIFF: /* FFFECC08 */
117 reg = OMAP_TC_EMIFF_PRIOR;
118 break;
119 case OMAP_DMA_PORT_EMIFS: /* FFFECC04 */
120 reg = OMAP_TC_EMIFS_PRIOR;
121 break;
122 default:
123 BUG();
124 return;
125 }
126 l = omap_readl(reg);
127 l &= ~(0xf << 8);
128 l |= (priority & 0xf) << 8;
129 omap_writel(l, reg);
130 }
131 }
132 EXPORT_SYMBOL(omap_set_dma_priority);
133 #endif
134
135 #if IS_ENABLED(CONFIG_USB_OMAP)
136 #ifdef CONFIG_ARCH_OMAP15XX
137 /* Returns 1 if the DMA module is in OMAP1510-compatible mode, 0 otherwise */
omap_dma_in_1510_mode(void)138 static int omap_dma_in_1510_mode(void)
139 {
140 return enable_1510_mode;
141 }
142 #else
143 #define omap_dma_in_1510_mode() 0
144 #endif
145
omap_set_dma_transfer_params(int lch,int data_type,int elem_count,int frame_count,int sync_mode,int dma_trigger,int src_or_dst_synch)146 void omap_set_dma_transfer_params(int lch, int data_type, int elem_count,
147 int frame_count, int sync_mode,
148 int dma_trigger, int src_or_dst_synch)
149 {
150 u32 l;
151 u16 ccr;
152
153 l = p->dma_read(CSDP, lch);
154 l &= ~0x03;
155 l |= data_type;
156 p->dma_write(l, CSDP, lch);
157
158 ccr = p->dma_read(CCR, lch);
159 ccr &= ~(1 << 5);
160 if (sync_mode == OMAP_DMA_SYNC_FRAME)
161 ccr |= 1 << 5;
162 p->dma_write(ccr, CCR, lch);
163
164 ccr = p->dma_read(CCR2, lch);
165 ccr &= ~(1 << 2);
166 if (sync_mode == OMAP_DMA_SYNC_BLOCK)
167 ccr |= 1 << 2;
168 p->dma_write(ccr, CCR2, lch);
169 p->dma_write(elem_count, CEN, lch);
170 p->dma_write(frame_count, CFN, lch);
171 }
172 EXPORT_SYMBOL(omap_set_dma_transfer_params);
173
omap_set_dma_channel_mode(int lch,enum omap_dma_channel_mode mode)174 void omap_set_dma_channel_mode(int lch, enum omap_dma_channel_mode mode)
175 {
176 if (!dma_omap15xx()) {
177 u32 l;
178
179 l = p->dma_read(LCH_CTRL, lch);
180 l &= ~0x7;
181 l |= mode;
182 p->dma_write(l, LCH_CTRL, lch);
183 }
184 }
185 EXPORT_SYMBOL(omap_set_dma_channel_mode);
186
187 /* Note that src_port is only for omap1 */
omap_set_dma_src_params(int lch,int src_port,int src_amode,unsigned long src_start,int src_ei,int src_fi)188 void omap_set_dma_src_params(int lch, int src_port, int src_amode,
189 unsigned long src_start,
190 int src_ei, int src_fi)
191 {
192 u32 l;
193 u16 w;
194
195 w = p->dma_read(CSDP, lch);
196 w &= ~(0x1f << 2);
197 w |= src_port << 2;
198 p->dma_write(w, CSDP, lch);
199
200 l = p->dma_read(CCR, lch);
201 l &= ~(0x03 << 12);
202 l |= src_amode << 12;
203 p->dma_write(l, CCR, lch);
204
205 p->dma_write(src_start, CSSA, lch);
206
207 p->dma_write(src_ei, CSEI, lch);
208 p->dma_write(src_fi, CSFI, lch);
209 }
210 EXPORT_SYMBOL(omap_set_dma_src_params);
211
omap_set_dma_src_data_pack(int lch,int enable)212 void omap_set_dma_src_data_pack(int lch, int enable)
213 {
214 u32 l;
215
216 l = p->dma_read(CSDP, lch);
217 l &= ~(1 << 6);
218 if (enable)
219 l |= (1 << 6);
220 p->dma_write(l, CSDP, lch);
221 }
222 EXPORT_SYMBOL(omap_set_dma_src_data_pack);
223
omap_set_dma_src_burst_mode(int lch,enum omap_dma_burst_mode burst_mode)224 void omap_set_dma_src_burst_mode(int lch, enum omap_dma_burst_mode burst_mode)
225 {
226 unsigned int burst = 0;
227 u32 l;
228
229 l = p->dma_read(CSDP, lch);
230 l &= ~(0x03 << 7);
231
232 switch (burst_mode) {
233 case OMAP_DMA_DATA_BURST_DIS:
234 break;
235 case OMAP_DMA_DATA_BURST_4:
236 burst = 0x2;
237 break;
238 case OMAP_DMA_DATA_BURST_8:
239 /*
240 * not supported by current hardware on OMAP1
241 * w |= (0x03 << 7);
242 */
243 fallthrough;
244 case OMAP_DMA_DATA_BURST_16:
245 /* OMAP1 don't support burst 16 */
246 fallthrough;
247 default:
248 BUG();
249 }
250
251 l |= (burst << 7);
252 p->dma_write(l, CSDP, lch);
253 }
254 EXPORT_SYMBOL(omap_set_dma_src_burst_mode);
255
256 /* Note that dest_port is only for OMAP1 */
omap_set_dma_dest_params(int lch,int dest_port,int dest_amode,unsigned long dest_start,int dst_ei,int dst_fi)257 void omap_set_dma_dest_params(int lch, int dest_port, int dest_amode,
258 unsigned long dest_start,
259 int dst_ei, int dst_fi)
260 {
261 u32 l;
262
263 l = p->dma_read(CSDP, lch);
264 l &= ~(0x1f << 9);
265 l |= dest_port << 9;
266 p->dma_write(l, CSDP, lch);
267
268 l = p->dma_read(CCR, lch);
269 l &= ~(0x03 << 14);
270 l |= dest_amode << 14;
271 p->dma_write(l, CCR, lch);
272
273 p->dma_write(dest_start, CDSA, lch);
274
275 p->dma_write(dst_ei, CDEI, lch);
276 p->dma_write(dst_fi, CDFI, lch);
277 }
278 EXPORT_SYMBOL(omap_set_dma_dest_params);
279
omap_set_dma_dest_data_pack(int lch,int enable)280 void omap_set_dma_dest_data_pack(int lch, int enable)
281 {
282 u32 l;
283
284 l = p->dma_read(CSDP, lch);
285 l &= ~(1 << 13);
286 if (enable)
287 l |= 1 << 13;
288 p->dma_write(l, CSDP, lch);
289 }
290 EXPORT_SYMBOL(omap_set_dma_dest_data_pack);
291
omap_set_dma_dest_burst_mode(int lch,enum omap_dma_burst_mode burst_mode)292 void omap_set_dma_dest_burst_mode(int lch, enum omap_dma_burst_mode burst_mode)
293 {
294 unsigned int burst = 0;
295 u32 l;
296
297 l = p->dma_read(CSDP, lch);
298 l &= ~(0x03 << 14);
299
300 switch (burst_mode) {
301 case OMAP_DMA_DATA_BURST_DIS:
302 break;
303 case OMAP_DMA_DATA_BURST_4:
304 burst = 0x2;
305 break;
306 case OMAP_DMA_DATA_BURST_8:
307 burst = 0x3;
308 break;
309 case OMAP_DMA_DATA_BURST_16:
310 /* OMAP1 don't support burst 16 */
311 fallthrough;
312 default:
313 printk(KERN_ERR "Invalid DMA burst mode\n");
314 BUG();
315 return;
316 }
317 l |= (burst << 14);
318 p->dma_write(l, CSDP, lch);
319 }
320 EXPORT_SYMBOL(omap_set_dma_dest_burst_mode);
321
omap_enable_channel_irq(int lch)322 static inline void omap_enable_channel_irq(int lch)
323 {
324 /* Clear CSR */
325 p->dma_read(CSR, lch);
326
327 /* Enable some nice interrupts. */
328 p->dma_write(dma_chan[lch].enabled_irqs, CICR, lch);
329 }
330
omap_disable_dma_irq(int lch,u16 bits)331 void omap_disable_dma_irq(int lch, u16 bits)
332 {
333 dma_chan[lch].enabled_irqs &= ~bits;
334 }
335 EXPORT_SYMBOL(omap_disable_dma_irq);
336
enable_lnk(int lch)337 static inline void enable_lnk(int lch)
338 {
339 u32 l;
340
341 l = p->dma_read(CLNK_CTRL, lch);
342
343 l &= ~(1 << 14);
344
345 /* Set the ENABLE_LNK bits */
346 if (dma_chan[lch].next_lch != -1)
347 l = dma_chan[lch].next_lch | (1 << 15);
348
349 p->dma_write(l, CLNK_CTRL, lch);
350 }
351
disable_lnk(int lch)352 static inline void disable_lnk(int lch)
353 {
354 u32 l;
355
356 l = p->dma_read(CLNK_CTRL, lch);
357
358 /* Disable interrupts */
359 omap_disable_channel_irq(lch);
360
361 /* Set the STOP_LNK bit */
362 l |= 1 << 14;
363
364 p->dma_write(l, CLNK_CTRL, lch);
365 dma_chan[lch].flags &= ~OMAP_DMA_ACTIVE;
366 }
367 #endif
368
omap_request_dma(int dev_id,const char * dev_name,void (* callback)(int lch,u16 ch_status,void * data),void * data,int * dma_ch_out)369 int omap_request_dma(int dev_id, const char *dev_name,
370 void (*callback)(int lch, u16 ch_status, void *data),
371 void *data, int *dma_ch_out)
372 {
373 int ch, free_ch = -1;
374 unsigned long flags;
375 struct omap_dma_lch *chan;
376
377 WARN(strcmp(dev_name, "DMA engine"), "Using deprecated platform DMA API - please update to DMA engine");
378
379 spin_lock_irqsave(&dma_chan_lock, flags);
380 for (ch = 0; ch < dma_chan_count; ch++) {
381 if (free_ch == -1 && dma_chan[ch].dev_id == -1) {
382 free_ch = ch;
383 /* Exit after first free channel found */
384 break;
385 }
386 }
387 if (free_ch == -1) {
388 spin_unlock_irqrestore(&dma_chan_lock, flags);
389 return -EBUSY;
390 }
391 chan = dma_chan + free_ch;
392 chan->dev_id = dev_id;
393
394 if (p->clear_lch_regs)
395 p->clear_lch_regs(free_ch);
396
397 spin_unlock_irqrestore(&dma_chan_lock, flags);
398
399 chan->dev_name = dev_name;
400 chan->callback = callback;
401 chan->data = data;
402 chan->flags = 0;
403
404 chan->enabled_irqs = OMAP_DMA_DROP_IRQ | OMAP_DMA_BLOCK_IRQ;
405
406 chan->enabled_irqs |= OMAP1_DMA_TOUT_IRQ;
407
408 if (dma_omap16xx()) {
409 /* If the sync device is set, configure it dynamically. */
410 if (dev_id != 0) {
411 set_gdma_dev(free_ch + 1, dev_id);
412 dev_id = free_ch + 1;
413 }
414 /*
415 * Disable the 1510 compatibility mode and set the sync device
416 * id.
417 */
418 p->dma_write(dev_id | (1 << 10), CCR, free_ch);
419 } else {
420 p->dma_write(dev_id, CCR, free_ch);
421 }
422
423 *dma_ch_out = free_ch;
424
425 return 0;
426 }
427 EXPORT_SYMBOL(omap_request_dma);
428
omap_free_dma(int lch)429 void omap_free_dma(int lch)
430 {
431 unsigned long flags;
432
433 if (dma_chan[lch].dev_id == -1) {
434 pr_err("omap_dma: trying to free unallocated DMA channel %d\n",
435 lch);
436 return;
437 }
438
439 /* Disable all DMA interrupts for the channel. */
440 omap_disable_channel_irq(lch);
441
442 /* Make sure the DMA transfer is stopped. */
443 p->dma_write(0, CCR, lch);
444
445 spin_lock_irqsave(&dma_chan_lock, flags);
446 dma_chan[lch].dev_id = -1;
447 dma_chan[lch].next_lch = -1;
448 dma_chan[lch].callback = NULL;
449 spin_unlock_irqrestore(&dma_chan_lock, flags);
450 }
451 EXPORT_SYMBOL(omap_free_dma);
452
453 /*
454 * Clears any DMA state so the DMA engine is ready to restart with new buffers
455 * through omap_start_dma(). Any buffers in flight are discarded.
456 */
omap_clear_dma(int lch)457 static void omap_clear_dma(int lch)
458 {
459 unsigned long flags;
460
461 local_irq_save(flags);
462 p->clear_dma(lch);
463 local_irq_restore(flags);
464 }
465
466 #if IS_ENABLED(CONFIG_USB_OMAP)
omap_start_dma(int lch)467 void omap_start_dma(int lch)
468 {
469 u32 l;
470
471 /*
472 * The CPC/CDAC register needs to be initialized to zero
473 * before starting dma transfer.
474 */
475 if (dma_omap15xx())
476 p->dma_write(0, CPC, lch);
477 else
478 p->dma_write(0, CDAC, lch);
479
480 if (!omap_dma_in_1510_mode() && dma_chan[lch].next_lch != -1) {
481 int next_lch, cur_lch;
482 char dma_chan_link_map[MAX_LOGICAL_DMA_CH_COUNT];
483
484 /* Set the link register of the first channel */
485 enable_lnk(lch);
486
487 memset(dma_chan_link_map, 0, sizeof(dma_chan_link_map));
488 dma_chan_link_map[lch] = 1;
489
490 cur_lch = dma_chan[lch].next_lch;
491 do {
492 next_lch = dma_chan[cur_lch].next_lch;
493
494 /* The loop case: we've been here already */
495 if (dma_chan_link_map[cur_lch])
496 break;
497 /* Mark the current channel */
498 dma_chan_link_map[cur_lch] = 1;
499
500 enable_lnk(cur_lch);
501 omap_enable_channel_irq(cur_lch);
502
503 cur_lch = next_lch;
504 } while (next_lch != -1);
505 } else if (IS_DMA_ERRATA(DMA_ERRATA_PARALLEL_CHANNELS))
506 p->dma_write(lch, CLNK_CTRL, lch);
507
508 omap_enable_channel_irq(lch);
509
510 l = p->dma_read(CCR, lch);
511
512 if (IS_DMA_ERRATA(DMA_ERRATA_IFRAME_BUFFERING))
513 l |= OMAP_DMA_CCR_BUFFERING_DISABLE;
514 l |= OMAP_DMA_CCR_EN;
515
516 /*
517 * As dma_write() uses IO accessors which are weakly ordered, there
518 * is no guarantee that data in coherent DMA memory will be visible
519 * to the DMA device. Add a memory barrier here to ensure that any
520 * such data is visible prior to enabling DMA.
521 */
522 mb();
523 p->dma_write(l, CCR, lch);
524
525 dma_chan[lch].flags |= OMAP_DMA_ACTIVE;
526 }
527 EXPORT_SYMBOL(omap_start_dma);
528
omap_stop_dma(int lch)529 void omap_stop_dma(int lch)
530 {
531 u32 l;
532
533 /* Disable all interrupts on the channel */
534 omap_disable_channel_irq(lch);
535
536 l = p->dma_read(CCR, lch);
537 if (IS_DMA_ERRATA(DMA_ERRATA_i541) &&
538 (l & OMAP_DMA_CCR_SEL_SRC_DST_SYNC)) {
539 int i = 0;
540 u32 sys_cf;
541
542 /* Configure No-Standby */
543 l = p->dma_read(OCP_SYSCONFIG, lch);
544 sys_cf = l;
545 l &= ~DMA_SYSCONFIG_MIDLEMODE_MASK;
546 l |= DMA_SYSCONFIG_MIDLEMODE(DMA_IDLEMODE_NO_IDLE);
547 p->dma_write(l , OCP_SYSCONFIG, 0);
548
549 l = p->dma_read(CCR, lch);
550 l &= ~OMAP_DMA_CCR_EN;
551 p->dma_write(l, CCR, lch);
552
553 /* Wait for sDMA FIFO drain */
554 l = p->dma_read(CCR, lch);
555 while (i < 100 && (l & (OMAP_DMA_CCR_RD_ACTIVE |
556 OMAP_DMA_CCR_WR_ACTIVE))) {
557 udelay(5);
558 i++;
559 l = p->dma_read(CCR, lch);
560 }
561 if (i >= 100)
562 pr_err("DMA drain did not complete on lch %d\n", lch);
563 /* Restore OCP_SYSCONFIG */
564 p->dma_write(sys_cf, OCP_SYSCONFIG, lch);
565 } else {
566 l &= ~OMAP_DMA_CCR_EN;
567 p->dma_write(l, CCR, lch);
568 }
569
570 /*
571 * Ensure that data transferred by DMA is visible to any access
572 * after DMA has been disabled. This is important for coherent
573 * DMA regions.
574 */
575 mb();
576
577 if (!omap_dma_in_1510_mode() && dma_chan[lch].next_lch != -1) {
578 int next_lch, cur_lch = lch;
579 char dma_chan_link_map[MAX_LOGICAL_DMA_CH_COUNT];
580
581 memset(dma_chan_link_map, 0, sizeof(dma_chan_link_map));
582 do {
583 /* The loop case: we've been here already */
584 if (dma_chan_link_map[cur_lch])
585 break;
586 /* Mark the current channel */
587 dma_chan_link_map[cur_lch] = 1;
588
589 disable_lnk(cur_lch);
590
591 next_lch = dma_chan[cur_lch].next_lch;
592 cur_lch = next_lch;
593 } while (next_lch != -1);
594 }
595
596 dma_chan[lch].flags &= ~OMAP_DMA_ACTIVE;
597 }
598 EXPORT_SYMBOL(omap_stop_dma);
599
600 /*
601 * Allows changing the DMA callback function or data. This may be needed if
602 * the driver shares a single DMA channel for multiple dma triggers.
603 */
604 /*
605 * Returns current physical source address for the given DMA channel.
606 * If the channel is running the caller must disable interrupts prior calling
607 * this function and process the returned value before re-enabling interrupt to
608 * prevent races with the interrupt handler. Note that in continuous mode there
609 * is a chance for CSSA_L register overflow between the two reads resulting
610 * in incorrect return value.
611 */
omap_get_dma_src_pos(int lch)612 dma_addr_t omap_get_dma_src_pos(int lch)
613 {
614 dma_addr_t offset = 0;
615
616 if (dma_omap15xx())
617 offset = p->dma_read(CPC, lch);
618 else
619 offset = p->dma_read(CSAC, lch);
620
621 if (IS_DMA_ERRATA(DMA_ERRATA_3_3) && offset == 0)
622 offset = p->dma_read(CSAC, lch);
623
624 if (!dma_omap15xx()) {
625 /*
626 * CDAC == 0 indicates that the DMA transfer on the channel has
627 * not been started (no data has been transferred so far).
628 * Return the programmed source start address in this case.
629 */
630 if (likely(p->dma_read(CDAC, lch)))
631 offset = p->dma_read(CSAC, lch);
632 else
633 offset = p->dma_read(CSSA, lch);
634 }
635
636 offset |= (p->dma_read(CSSA, lch) & 0xFFFF0000);
637
638 return offset;
639 }
640 EXPORT_SYMBOL(omap_get_dma_src_pos);
641
642 /*
643 * Returns current physical destination address for the given DMA channel.
644 * If the channel is running the caller must disable interrupts prior calling
645 * this function and process the returned value before re-enabling interrupt to
646 * prevent races with the interrupt handler. Note that in continuous mode there
647 * is a chance for CDSA_L register overflow between the two reads resulting
648 * in incorrect return value.
649 */
omap_get_dma_dst_pos(int lch)650 dma_addr_t omap_get_dma_dst_pos(int lch)
651 {
652 dma_addr_t offset = 0;
653
654 if (dma_omap15xx())
655 offset = p->dma_read(CPC, lch);
656 else
657 offset = p->dma_read(CDAC, lch);
658
659 /*
660 * omap 3.2/3.3 erratum: sometimes 0 is returned if CSAC/CDAC is
661 * read before the DMA controller finished disabling the channel.
662 */
663 if (!dma_omap15xx() && offset == 0) {
664 offset = p->dma_read(CDAC, lch);
665 /*
666 * CDAC == 0 indicates that the DMA transfer on the channel has
667 * not been started (no data has been transferred so far).
668 * Return the programmed destination start address in this case.
669 */
670 if (unlikely(!offset))
671 offset = p->dma_read(CDSA, lch);
672 }
673
674 offset |= (p->dma_read(CDSA, lch) & 0xFFFF0000);
675
676 return offset;
677 }
678 EXPORT_SYMBOL(omap_get_dma_dst_pos);
679
omap_get_dma_active_status(int lch)680 int omap_get_dma_active_status(int lch)
681 {
682 return (p->dma_read(CCR, lch) & OMAP_DMA_CCR_EN) != 0;
683 }
684 EXPORT_SYMBOL(omap_get_dma_active_status);
685 #endif
686
omap_dma_running(void)687 int omap_dma_running(void)
688 {
689 int lch;
690
691 if (omap_lcd_dma_running())
692 return 1;
693
694 for (lch = 0; lch < dma_chan_count; lch++)
695 if (p->dma_read(CCR, lch) & OMAP_DMA_CCR_EN)
696 return 1;
697
698 return 0;
699 }
700
701 /*----------------------------------------------------------------------------*/
702
omap1_dma_handle_ch(int ch)703 static int omap1_dma_handle_ch(int ch)
704 {
705 u32 csr;
706
707 if (enable_1510_mode && ch >= 6) {
708 csr = dma_chan[ch].saved_csr;
709 dma_chan[ch].saved_csr = 0;
710 } else
711 csr = p->dma_read(CSR, ch);
712 if (enable_1510_mode && ch <= 2 && (csr >> 7) != 0) {
713 dma_chan[ch + 6].saved_csr = csr >> 7;
714 csr &= 0x7f;
715 }
716 if ((csr & 0x3f) == 0)
717 return 0;
718 if (unlikely(dma_chan[ch].dev_id == -1)) {
719 pr_warn("Spurious interrupt from DMA channel %d (CSR %04x)\n",
720 ch, csr);
721 return 0;
722 }
723 if (unlikely(csr & OMAP1_DMA_TOUT_IRQ))
724 pr_warn("DMA timeout with device %d\n", dma_chan[ch].dev_id);
725 if (unlikely(csr & OMAP_DMA_DROP_IRQ))
726 pr_warn("DMA synchronization event drop occurred with device %d\n",
727 dma_chan[ch].dev_id);
728 if (likely(csr & OMAP_DMA_BLOCK_IRQ))
729 dma_chan[ch].flags &= ~OMAP_DMA_ACTIVE;
730 if (likely(dma_chan[ch].callback != NULL))
731 dma_chan[ch].callback(ch, csr, dma_chan[ch].data);
732
733 return 1;
734 }
735
omap1_dma_irq_handler(int irq,void * dev_id)736 static irqreturn_t omap1_dma_irq_handler(int irq, void *dev_id)
737 {
738 int ch = ((int) dev_id) - 1;
739 int handled = 0;
740
741 for (;;) {
742 int handled_now = 0;
743
744 handled_now += omap1_dma_handle_ch(ch);
745 if (enable_1510_mode && dma_chan[ch + 6].saved_csr)
746 handled_now += omap1_dma_handle_ch(ch + 6);
747 if (!handled_now)
748 break;
749 handled += handled_now;
750 }
751
752 return handled ? IRQ_HANDLED : IRQ_NONE;
753 }
754
omap_get_plat_info(void)755 struct omap_system_dma_plat_info *omap_get_plat_info(void)
756 {
757 return p;
758 }
759 EXPORT_SYMBOL_GPL(omap_get_plat_info);
760
omap_system_dma_probe(struct platform_device * pdev)761 static int omap_system_dma_probe(struct platform_device *pdev)
762 {
763 int ch, ret = 0;
764 int dma_irq;
765 char irq_name[4];
766
767 p = pdev->dev.platform_data;
768 if (!p) {
769 dev_err(&pdev->dev,
770 "%s: System DMA initialized without platform data\n",
771 __func__);
772 return -EINVAL;
773 }
774
775 d = p->dma_attr;
776 errata = p->errata;
777
778 if ((d->dev_caps & RESERVE_CHANNEL) && omap_dma_reserve_channels
779 && (omap_dma_reserve_channels < d->lch_count))
780 d->lch_count = omap_dma_reserve_channels;
781
782 dma_lch_count = d->lch_count;
783 dma_chan_count = dma_lch_count;
784 enable_1510_mode = d->dev_caps & ENABLE_1510_MODE;
785
786 dma_chan = devm_kcalloc(&pdev->dev, dma_lch_count,
787 sizeof(*dma_chan), GFP_KERNEL);
788 if (!dma_chan)
789 return -ENOMEM;
790
791 for (ch = 0; ch < dma_chan_count; ch++) {
792 omap_clear_dma(ch);
793
794 dma_chan[ch].dev_id = -1;
795 dma_chan[ch].next_lch = -1;
796
797 if (ch >= 6 && enable_1510_mode)
798 continue;
799
800 /*
801 * request_irq() doesn't like dev_id (ie. ch) being
802 * zero, so we have to kludge around this.
803 */
804 sprintf(&irq_name[0], "%d", ch);
805 dma_irq = platform_get_irq_byname(pdev, irq_name);
806
807 if (dma_irq < 0) {
808 ret = dma_irq;
809 goto exit_dma_irq_fail;
810 }
811
812 /* INT_DMA_LCD is handled in lcd_dma.c */
813 if (dma_irq == INT_DMA_LCD)
814 continue;
815
816 ret = request_irq(dma_irq,
817 omap1_dma_irq_handler, 0, "DMA",
818 (void *) (ch + 1));
819 if (ret != 0)
820 goto exit_dma_irq_fail;
821 }
822
823 /* reserve dma channels 0 and 1 in high security devices on 34xx */
824 if (d->dev_caps & HS_CHANNELS_RESERVED) {
825 pr_info("Reserving DMA channels 0 and 1 for HS ROM code\n");
826 dma_chan[0].dev_id = 0;
827 dma_chan[1].dev_id = 1;
828 }
829 p->show_dma_caps();
830 return 0;
831
832 exit_dma_irq_fail:
833 return ret;
834 }
835
omap_system_dma_remove(struct platform_device * pdev)836 static void omap_system_dma_remove(struct platform_device *pdev)
837 {
838 int dma_irq, irq_rel = 0;
839
840 for ( ; irq_rel < dma_chan_count; irq_rel++) {
841 dma_irq = platform_get_irq(pdev, irq_rel);
842 free_irq(dma_irq, (void *)(irq_rel + 1));
843 }
844 }
845
846 static struct platform_driver omap_system_dma_driver = {
847 .probe = omap_system_dma_probe,
848 .remove_new = omap_system_dma_remove,
849 .driver = {
850 .name = "omap_dma_system"
851 },
852 };
853
omap_system_dma_init(void)854 static int __init omap_system_dma_init(void)
855 {
856 return platform_driver_register(&omap_system_dma_driver);
857 }
858 arch_initcall(omap_system_dma_init);
859
omap_system_dma_exit(void)860 static void __exit omap_system_dma_exit(void)
861 {
862 platform_driver_unregister(&omap_system_dma_driver);
863 }
864
865 MODULE_DESCRIPTION("OMAP SYSTEM DMA DRIVER");
866 MODULE_LICENSE("GPL");
867 MODULE_AUTHOR("Texas Instruments Inc");
868
869 /*
870 * Reserve the omap SDMA channels using cmdline bootarg
871 * "omap_dma_reserve_ch=". The valid range is 1 to 32
872 */
omap_dma_cmdline_reserve_ch(char * str)873 static int __init omap_dma_cmdline_reserve_ch(char *str)
874 {
875 if (get_option(&str, &omap_dma_reserve_channels) != 1)
876 omap_dma_reserve_channels = 0;
877 return 1;
878 }
879
880 __setup("omap_dma_reserve_ch=", omap_dma_cmdline_reserve_ch);
881
882
883