diff options
Diffstat (limited to 'firmware/target/arm')
-rw-r--r-- | firmware/target/arm/s5l8702/pl080.c | 580 |
1 files changed, 580 insertions, 0 deletions
diff --git a/firmware/target/arm/s5l8702/pl080.c b/firmware/target/arm/s5l8702/pl080.c new file mode 100644 index 0000000000..d7b3a3173f --- /dev/null +++ b/firmware/target/arm/s5l8702/pl080.c | |||
@@ -0,0 +1,580 @@ | |||
1 | /*************************************************************************** | ||
2 | * __________ __ ___. | ||
3 | * Open \______ \ ____ ____ | | _\_ |__ _______ ___ | ||
4 | * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / | ||
5 | * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < | ||
6 | * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ | ||
7 | * \/ \/ \/ \/ \/ | ||
8 | * $Id$ | ||
9 | * | ||
10 | * Copyright (C) 2014 by Cástor Muñoz | ||
11 | * | ||
12 | * This program is free software; you can redistribute it and/or | ||
13 | * modify it under the terms of the GNU General Public License | ||
14 | * as published by the Free Software Foundation; either version 2 | ||
15 | * of the License, or (at your option) any later version. | ||
16 | * | ||
17 | * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY | ||
18 | * KIND, either express or implied. | ||
19 | * | ||
20 | ****************************************************************************/ | ||
21 | #include "config.h" | ||
22 | #include <stddef.h> | ||
23 | #include "system.h" | ||
24 | #include "pl080.h" | ||
25 | #include "panic.h" | ||
26 | |||
27 | /* | ||
28 | * ARM PrimeCell PL080 Multiple Master DMA controller | ||
29 | */ | ||
30 | |||
31 | /*#define PANIC_DEBUG*/ | ||
32 | #ifdef PANIC_DEBUG | ||
33 | void dmac_ch_panicf(const char *fn, struct dmac_ch* ch) | ||
34 | { | ||
35 | char *err = NULL; | ||
36 | |||
37 | if (!ch) | ||
38 | err = "NULL channel"; | ||
39 | else if (!ch->dmac) | ||
40 | err = "NULL ch->dmac"; | ||
41 | else if (ch->dmac->ch_l[ch->prio] != ch) | ||
42 | err = "not initialized channel"; | ||
43 | |||
44 | if (err) | ||
45 | panicf("%s(): <%d> %s", fn, ch ? (int)ch->prio : -1, err); | ||
46 | } | ||
47 | #define PANIC_DEBUG_CHANNEL(ch) dmac_ch_panicf(__func__,(ch)) | ||
48 | #else | ||
49 | #define PANIC_DEBUG_CHANNEL(ch) {} | ||
50 | #endif | ||
51 | |||
52 | /* task helpers */ | ||
53 | static inline struct dmac_tsk *dmac_ch_tsk_by_idx( | ||
54 | struct dmac_ch *ch, uint32_t idx) | ||
55 | { | ||
56 | return ch->tskbuf + (idx & ch->tskbuf_mask); | ||
57 | } | ||
58 | #define CH_TSK_TOP(ch) dmac_ch_tsk_by_idx((ch), (ch)->tasks_queued) | ||
59 | #define CH_TSK_TAIL(ch) dmac_ch_tsk_by_idx((ch), (ch)->tasks_done) | ||
60 | |||
61 | static inline bool dmac_ch_task_queue_empty(struct dmac_ch *ch) | ||
62 | { | ||
63 | return (ch->tasks_done == ch->tasks_queued); | ||
64 | } | ||
65 | |||
66 | /* enable/disable DMA controller */ | ||
67 | static inline void dmac_hw_enable(struct dmac *dmac) | ||
68 | { | ||
69 | DMACCONFIG(dmac->baddr) |= DMACCONFIG_E_BIT; | ||
70 | } | ||
71 | |||
72 | static inline void dmac_hw_disable(struct dmac *dmac) | ||
73 | { | ||
74 | DMACCONFIG(dmac->baddr) &= ~DMACCONFIG_E_BIT; | ||
75 | } | ||
76 | |||
77 | /* enable/disable DMA channel */ | ||
78 | static inline void dmac_ch_enable(struct dmac_ch *ch) | ||
79 | { | ||
80 | DMACCxCONFIG(ch->baddr) |= DMACCxCONFIG_E_BIT; | ||
81 | } | ||
82 | |||
83 | static inline void dmac_ch_disable(struct dmac_ch *ch) | ||
84 | { | ||
85 | uint32_t baddr = ch->baddr; | ||
86 | |||
87 | /* Disable the channel, clears the FIFO after | ||
88 | completing current AHB transfer */ | ||
89 | DMACCxCONFIG(baddr) &= ~DMACCxCONFIG_E_BIT; | ||
90 | /* Wait for it to go inactive */ | ||
91 | while (DMACCxCONFIG(baddr) & DMACCxCONFIG_A_BIT); | ||
92 | } | ||
93 | |||
94 | #if 0 | ||
95 | static void dmac_ch_halt(struct dmac_ch *ch) | ||
96 | { | ||
97 | uint32_t baddr = ch->baddr; | ||
98 | |||
99 | /* Halt the channel, ignores subsequent DMA requests, | ||
100 | the contents of the FIFO are drained */ | ||
101 | DMACCxCONFIG(baddr) |= DMACCxCONFIG_H_BIT; | ||
102 | /* Wait for it to go inactive */ | ||
103 | while (DMACCxCONFIG(baddr) & DMACCxCONFIG_A_BIT); | ||
104 | /* Disable channel and restore Halt bit */ | ||
105 | DMACCxCONFIG(baddr) &= ~(DMACCxCONFIG_H_BIT | DMACCxCONFIG_E_BIT); | ||
106 | } | ||
107 | #endif | ||
108 | |||
109 | /* launch next task in queue */ | ||
110 | static void ICODE_ATTR dmac_ch_run(struct dmac_ch *ch) | ||
111 | { | ||
112 | struct dmac *dmac = ch->dmac; | ||
113 | |||
114 | if (!dmac->ch_run_status) | ||
115 | dmac_hw_enable(dmac); | ||
116 | dmac->ch_run_status |= (1 << ch->prio); | ||
117 | |||
118 | /* Clear any pending interrupts leftover from previous operation */ | ||
119 | /*DMACINTTCCLR(dmac->baddr) = (1 << ch->prio);*/ /* not needed */ | ||
120 | |||
121 | /* copy whole LLI to HW registers */ | ||
122 | *DMACCxLLI(ch->baddr) = *(CH_TSK_TAIL(ch)->start_lli); | ||
123 | |||
124 | dmac_ch_enable(ch); | ||
125 | } | ||
126 | |||
127 | static void ICODE_ATTR dmac_ch_abort(struct dmac_ch* ch) | ||
128 | { | ||
129 | struct dmac *dmac = ch->dmac; | ||
130 | |||
131 | dmac_ch_disable(ch); | ||
132 | |||
133 | /* Clear any pending interrupt */ | ||
134 | DMACINTTCCLR(dmac->baddr) = (1 << ch->prio); | ||
135 | |||
136 | dmac->ch_run_status &= ~(1 << ch->prio); | ||
137 | if (!dmac->ch_run_status) | ||
138 | dmac_hw_disable(dmac); | ||
139 | } | ||
140 | |||
141 | /* ISR */ | ||
142 | static inline void dmac_ch_callback(struct dmac_ch *ch) | ||
143 | { | ||
144 | PANIC_DEBUG_CHANNEL(ch); | ||
145 | |||
146 | /* backup current task cb_data */ | ||
147 | void *cb_data = CH_TSK_TAIL(ch)->cb_data; | ||
148 | |||
149 | /* mark current task as finished (resources can be reused) */ | ||
150 | ch->tasks_done++; | ||
151 | |||
152 | /* launch next DMA task */ | ||
153 | if (ch->queue_mode == QUEUE_NORMAL) | ||
154 | if (!dmac_ch_task_queue_empty(ch)) | ||
155 | dmac_ch_run(ch); | ||
156 | |||
157 | /* run user callback, new tasks could be launched/queued here */ | ||
158 | if (ch->cb_fn) | ||
159 | ch->cb_fn(cb_data); | ||
160 | |||
161 | /* disable DMA channel if there are no running tasks */ | ||
162 | if (dmac_ch_task_queue_empty(ch)) | ||
163 | dmac_ch_abort(ch); | ||
164 | } | ||
165 | |||
166 | void ICODE_ATTR dmac_callback(struct dmac *dmac) | ||
167 | { | ||
168 | #ifdef PANIC_DEBUG | ||
169 | if (!dmac) | ||
170 | panicf("dmac_callback(): NULL dmac"); | ||
171 | #endif | ||
172 | |||
173 | unsigned int ch_n; | ||
174 | uint32_t baddr = dmac->baddr; | ||
175 | uint32_t intsts = DMACINTSTS(baddr); | ||
176 | |||
177 | /* Lowest channel index is serviced first */ | ||
178 | for (ch_n = 0; ch_n < DMAC_CH_COUNT; ch_n++) { | ||
179 | if ((intsts & (1 << ch_n))) { | ||
180 | if (DMACINTERRSTS(baddr) & (1 << ch_n)) | ||
181 | panicf("DMA ch%d: HW error", ch_n); | ||
182 | |||
183 | /* clear terminal count interrupt */ | ||
184 | DMACINTTCCLR(baddr) = (1 << ch_n); | ||
185 | |||
186 | dmac_ch_callback(dmac->ch_l[ch_n]); | ||
187 | } | ||
188 | } | ||
189 | } | ||
190 | |||
191 | /* | ||
192 | * API | ||
193 | */ | ||
194 | void dmac_open(struct dmac *dmac) | ||
195 | { | ||
196 | uint32_t baddr = dmac->baddr; | ||
197 | int ch_n; | ||
198 | |||
199 | dmac_hw_enable(dmac); | ||
200 | |||
201 | DMACCONFIG(baddr) = ((dmac->m1 & DMACCONFIG_M1_MSK) << DMACCONFIG_M1_POS) | ||
202 | | ((dmac->m2 & DMACCONFIG_M2_MSK) << DMACCONFIG_M2_POS); | ||
203 | |||
204 | for (ch_n = 0; ch_n < DMAC_CH_COUNT; ch_n++) { | ||
205 | DMACCxCONFIG(DMAC_CH_BASE(baddr, ch_n)) = 0; /* disable channel */ | ||
206 | dmac->ch_l[ch_n] = NULL; | ||
207 | } | ||
208 | dmac->ch_run_status = 0; | ||
209 | |||
210 | /* clear channel interrupts */ | ||
211 | DMACINTTCCLR(baddr) = 0xff; | ||
212 | DMACINTERRCLR(baddr) = 0xff; | ||
213 | |||
214 | dmac_hw_disable(dmac); | ||
215 | } | ||
216 | |||
217 | void dmac_ch_init(struct dmac_ch *ch, struct dmac_ch_cfg *cfg) | ||
218 | { | ||
219 | #ifdef PANIC_DEBUG | ||
220 | if (!ch) | ||
221 | panicf("%s(): NULL channel", __func__); | ||
222 | else if (!ch->dmac) | ||
223 | panicf("%s(): NULL ch->dmac", __func__); | ||
224 | else if (ch->dmac->ch_l[ch->prio]) | ||
225 | panicf("%s(): channel %d already initilized", __func__, ch->prio); | ||
226 | uint32_t align_mask = (1 << MIN(cfg->swidth, cfg->dwidth)) - 1; | ||
227 | if (ch->cfg->lli_xfer_max_count & align_mask) | ||
228 | panicf("%s(): bad bus width: sw=%u dw=%u max_cnt=%u", __func__, | ||
229 | cfg->swidth, cfg->dwidth, ch->cfg->lli_xfer_max_count); | ||
230 | #endif | ||
231 | |||
232 | struct dmac *dmac = ch->dmac; | ||
233 | int ch_n = ch->prio; | ||
234 | |||
235 | dmac->ch_l[ch_n] = ch; | ||
236 | |||
237 | ch->baddr = DMAC_CH_BASE(dmac->baddr, ch_n); | ||
238 | ch->llibuf_top = ch->llibuf; | ||
239 | ch->tasks_queued = 0; | ||
240 | ch->tasks_done = 0; | ||
241 | ch->cfg = cfg; | ||
242 | |||
243 | ch->control = | ||
244 | ((cfg->sbsize & DMACCxCONTROL_SBSIZE_MSK) << DMACCxCONTROL_SBSIZE_POS) | | ||
245 | ((cfg->dbsize & DMACCxCONTROL_DBSIZE_MSK) << DMACCxCONTROL_DBSIZE_POS) | | ||
246 | ((cfg->swidth & DMACCxCONTROL_SWIDTH_MSK) << DMACCxCONTROL_SWIDTH_POS) | | ||
247 | ((cfg->dwidth & DMACCxCONTROL_DWIDTH_MSK) << DMACCxCONTROL_DWIDTH_POS) | | ||
248 | ((cfg->sbus & DMACCxCONTROL_S_MSK) << DMACCxCONTROL_S_POS) | | ||
249 | ((cfg->dbus & DMACCxCONTROL_D_MSK) << DMACCxCONTROL_D_POS) | | ||
250 | ((cfg->sinc & DMACCxCONTROL_SI_MSK) << DMACCxCONTROL_SI_POS) | | ||
251 | ((cfg->dinc & DMACCxCONTROL_DI_MSK) << DMACCxCONTROL_DI_POS) | | ||
252 | ((cfg->prot & DMACCxCONTROL_PROT_MSK) << DMACCxCONTROL_PROT_POS); | ||
253 | |||
254 | /* flow control notes: | ||
255 | * - currently only master modes are supported (FLOWCNTRL_x_DMA). | ||
256 | * - must use DMAC_PERI_NONE when srcperi and/or dstperi are memory. | ||
257 | */ | ||
258 | uint32_t flowcntrl = (((cfg->srcperi != DMAC_PERI_NONE) << 1) | | ||
259 | (cfg->dstperi != DMAC_PERI_NONE)) << DMACCxCONFIG_FLOWCNTRL_POS; | ||
260 | |||
261 | DMACCxCONFIG(ch->baddr) = | ||
262 | ((cfg->srcperi & DMACCxCONFIG_SRCPERI_MSK) << DMACCxCONFIG_SRCPERI_POS) | | ||
263 | ((cfg->dstperi & DMACCxCONFIG_DESTPERI_MSK) << DMACCxCONFIG_DESTPERI_POS) | | ||
264 | flowcntrl | DMACCxCONFIG_IE_BIT | DMACCxCONFIG_ITC_BIT; | ||
265 | } | ||
266 | |||
267 | void dmac_ch_lock_int(struct dmac_ch *ch) | ||
268 | { | ||
269 | PANIC_DEBUG_CHANNEL(ch); | ||
270 | |||
271 | int flags = disable_irq_save(); | ||
272 | DMACCxCONFIG(ch->baddr) &= ~DMACCxCONFIG_ITC_BIT; | ||
273 | restore_irq(flags); | ||
274 | } | ||
275 | |||
276 | void dmac_ch_unlock_int(struct dmac_ch *ch) | ||
277 | { | ||
278 | PANIC_DEBUG_CHANNEL(ch); | ||
279 | |||
280 | int flags = disable_irq_save(); | ||
281 | DMACCxCONFIG(ch->baddr) |= DMACCxCONFIG_ITC_BIT; | ||
282 | restore_irq(flags); | ||
283 | } | ||
284 | |||
285 | /* 1D->2D DMA transfers: | ||
286 | * | ||
287 | * srcaddr: aaaaaaaaaaabbbbbbbbbbbccccccc | ||
288 | * <- size -> | ||
289 | * <- width -><- width -><- r -> | ||
290 | * | ||
291 | * dstaddr: aaaaaaaaaaa..... | ||
292 | * dstaddr + stride: bbbbbbbbbbb..... | ||
293 | * dstaddr + 2*stride: ccccccc......... | ||
294 | * <- stride -> | ||
295 | * <- width -> | ||
296 | * | ||
297 | * 1D->1D DMA transfers: | ||
298 | * | ||
299 | * If 'width'=='stride', uses 'lli_xfer_max_count' for LLI count. | ||
300 | * | ||
301 | * Queue modes: | ||
302 | * | ||
303 | * QUEUE_NORMAL: each task in the queue is launched using a new | ||
304 | * DMA transfer once previous task is finished. | ||
305 | * | ||
306 | * QUEUE_LINK: when a task is queued, it is linked with the last | ||
307 | * queued task, creating a single continuous DMA transfer. New | ||
308 | * tasks must be queued while the channel is running, otherwise | ||
309 | * the continuous DMA transfer will be broken. | ||
310 | * | ||
311 | * Misc notes: | ||
312 | * | ||
313 | * Arguments 'size', 'width' and 'stride' are in bytes. | ||
314 | * | ||
315 | * Maximum supported 'width' depends on bus 'swidth' size, it is: | ||
316 | * maximum width = DMAC_LLI_MAX_COUNT << swidth | ||
317 | * | ||
318 | * User must supply 'srcaddr', 'dstaddr', 'width', 'size', 'stride' | ||
319 | * and 'lli_xfer_max_count' aligned to configured source and | ||
320 | * destination bus widths, otherwise transfers will be internally | ||
321 | * aligned by DMA hardware. | ||
322 | */ | ||
323 | #define LLI_COUNT(lli) ((lli)->control & DMACCxCONTROL_COUNT_MSK) | ||
324 | #define LNK2LLI(link) ((struct dmac_lli*) ((link) & ~3)) | ||
325 | |||
326 | static inline void drain_write_buffer(void) | ||
327 | { | ||
328 | asm volatile ( | ||
329 | "mcr p15, 0, %0, c7, c10, 4\n" | ||
330 | : : "r"(0)); | ||
331 | } | ||
332 | |||
333 | static inline void clean_dcache_line(void volatile *addr) | ||
334 | { | ||
335 | asm volatile ( | ||
336 | "mcr p15, 0, %0, c7, c10, 1\n" /* clean d-cache line by MVA */ | ||
337 | : : "r"((uint32_t)addr & ~(CACHEALIGN_SIZE - 1))); | ||
338 | } | ||
339 | |||
340 | void ICODE_ATTR dmac_ch_queue_2d( | ||
341 | struct dmac_ch *ch, void *srcaddr, void *dstaddr, | ||
342 | size_t size, size_t width, size_t stride, void *cb_data) | ||
343 | { | ||
344 | #ifdef PANIC_DEBUG | ||
345 | PANIC_DEBUG_CHANNEL(ch); | ||
346 | uint32_t align = (1 << MIN(ch->cfg->swidth, ch->cfg->dwidth)) - 1; | ||
347 | if (((uint32_t)srcaddr | (uint32_t)dstaddr | size | width | stride) & align) | ||
348 | panicf("dmac_ch_queue_2d(): %d,%p,%p,%u,%u,%u: bad alignment?", | ||
349 | ch->prio, srcaddr, dstaddr, size, width, stride); | ||
350 | #endif | ||
351 | |||
352 | struct dmac_tsk *tsk; | ||
353 | unsigned int srcinc, dstinc; | ||
354 | uint32_t control, llibuf_idx; | ||
355 | struct dmac_lli volatile *lli, *next_lli; | ||
356 | |||
357 | /* get and fill new task */ | ||
358 | tsk = CH_TSK_TOP(ch); | ||
359 | tsk->start_lli = ch->llibuf_top; | ||
360 | tsk->size = size; | ||
361 | tsk->cb_data = cb_data; | ||
362 | |||
363 | /* use maximum LLI transfer count for 1D->1D transfers */ | ||
364 | if (width == stride) | ||
365 | width = stride = ch->cfg->lli_xfer_max_count << ch->cfg->swidth; | ||
366 | |||
367 | srcinc = (ch->cfg->sinc) ? stride : 0; | ||
368 | dstinc = (ch->cfg->dinc) ? width : 0; | ||
369 | |||
370 | size >>= ch->cfg->swidth; | ||
371 | width >>= ch->cfg->swidth; | ||
372 | |||
373 | /* fill LLI circular buffer */ | ||
374 | control = ch->control | width; | ||
375 | lli = ch->llibuf_top; | ||
376 | llibuf_idx = lli - ch->llibuf; | ||
377 | |||
378 | while (1) | ||
379 | { | ||
380 | llibuf_idx = (llibuf_idx + 1) & ch->llibuf_mask; | ||
381 | next_lli = ch->llibuf + llibuf_idx; | ||
382 | |||
383 | lli->srcaddr = srcaddr; | ||
384 | lli->dstaddr = dstaddr; | ||
385 | |||
386 | if (size <= width) | ||
387 | break; | ||
388 | |||
389 | lli->link = (uint32_t)next_lli | ch->llibuf_bus; | ||
390 | lli->control = control; | ||
391 | |||
392 | srcaddr += srcinc; | ||
393 | dstaddr += dstinc; | ||
394 | size -= width; | ||
395 | |||
396 | /* clean dcache after completing a line */ | ||
397 | if (((uint32_t)next_lli & (CACHEALIGN_SIZE - 1)) == 0) | ||
398 | clean_dcache_line(lli); | ||
399 | |||
400 | lli = next_lli; | ||
401 | } | ||
402 | /* last lli, enable terminal count interrupt */ | ||
403 | lli->link = 0; | ||
404 | lli->control = ch->control | size | DMACCxCONTROL_I_BIT; | ||
405 | clean_dcache_line(lli); | ||
406 | drain_write_buffer(); | ||
407 | |||
408 | tsk->end_lli = lli; | ||
409 | |||
410 | /* previous code is not protected against IRQs, it is fine to | ||
411 | enter the DMA interrupt handler while an application is | ||
412 | queuing a task, but the aplication must be protected when | ||
413 | doing concurrent queueing. */ | ||
414 | |||
415 | int flags = disable_irq_save(); | ||
416 | |||
417 | ch->llibuf_top = next_lli; | ||
418 | |||
419 | /* queue new task, launch it if it is the only queued task */ | ||
420 | if (ch->tasks_done == ch->tasks_queued++) | ||
421 | { | ||
422 | dmac_ch_run(ch); | ||
423 | } | ||
424 | else if (ch->queue_mode == QUEUE_LINK) | ||
425 | { | ||
426 | uint32_t baddr = ch->baddr; | ||
427 | uint32_t link, hw_link; | ||
428 | |||
429 | link = (uint32_t)tsk->start_lli | ch->llibuf_bus; | ||
430 | hw_link = DMACCxLINK(baddr); | ||
431 | |||
432 | /* if it is a direct HW link, do it ASAP */ | ||
433 | if (!hw_link) { | ||
434 | DMACCxLINK(baddr) = link; | ||
435 | /* check if the link was successful */ | ||
436 | link = DMACCxLINK(baddr); /* dummy read for delay */ | ||
437 | if (!(DMACCxCONFIG(baddr) & DMACCxCONFIG_E_BIT)) | ||
438 | panicf("DMA ch%d: link error", ch->prio); | ||
439 | } | ||
440 | |||
441 | /* Locate the LLI where the new task must be linked. Link it even | ||
442 | if it was a direct HW link, dmac_ch_get_info() needs it. */ | ||
443 | lli = dmac_ch_tsk_by_idx(ch, ch->tasks_queued-2)->end_lli; | ||
444 | lli->link = link; | ||
445 | clean_dcache_line(lli); | ||
446 | drain_write_buffer(); | ||
447 | |||
448 | /* If the updated LLI was loaded by the HW while it was being | ||
449 | modified, verify that the HW link is correct. */ | ||
450 | if (LNK2LLI(hw_link) == lli) { | ||
451 | uint32_t cur_hw_link = DMACCxLINK(baddr); | ||
452 | if ((cur_hw_link != hw_link) && (cur_hw_link != link)) | ||
453 | DMACCxLINK(baddr) = link; | ||
454 | } | ||
455 | } | ||
456 | |||
457 | restore_irq(flags); | ||
458 | } | ||
459 | |||
460 | void dmac_ch_stop(struct dmac_ch* ch) | ||
461 | { | ||
462 | PANIC_DEBUG_CHANNEL(ch); | ||
463 | |||
464 | int flags = disable_irq_save(); | ||
465 | dmac_ch_abort(ch); | ||
466 | ch->tasks_done = ch->tasks_queued; /* clear queue */ | ||
467 | restore_irq(flags); | ||
468 | } | ||
469 | |||
470 | bool dmac_ch_running(struct dmac_ch *ch) | ||
471 | { | ||
472 | PANIC_DEBUG_CHANNEL(ch); | ||
473 | |||
474 | int flags = disable_irq_save(); | ||
475 | bool running = !dmac_ch_task_queue_empty(ch); | ||
476 | restore_irq(flags); | ||
477 | return running; | ||
478 | } | ||
479 | |||
480 | /* returns source or destination address of the actual LLI transfer, | ||
481 | remaining bytes for current task, and total remaining bytes */ | ||
482 | void *dmac_ch_get_info(struct dmac_ch *ch, size_t *bytes, size_t *t_bytes) | ||
483 | { | ||
484 | PANIC_DEBUG_CHANNEL(ch); | ||
485 | |||
486 | void *cur_addr = NULL; | ||
487 | size_t count = 0, t_count = 0; | ||
488 | |||
489 | int flags = disable_irq_save(); | ||
490 | |||
491 | if (!dmac_ch_task_queue_empty(ch)) | ||
492 | { | ||
493 | struct dmac_lli volatile *cur_lli; | ||
494 | struct dmac_tsk *tsk; | ||
495 | uint32_t cur_task; /* index */ | ||
496 | uint32_t baddr = ch->baddr; | ||
497 | |||
498 | /* Read DMA transfer progress: | ||
499 | * | ||
500 | * The recommended procedure (stop channel -> read progress -> | ||
501 | * relaunch channel) is problematic for real time transfers, | ||
502 | * specially when fast sample rates are combined with small | ||
503 | * pheripheral FIFOs. | ||
504 | * | ||
505 | * An experimental method is used, it is based on the results | ||
506 | * observed when reading the LLI registers at the instant they | ||
507 | * are being updated by the HW (using s5l8702, 2:1 CPU/AHB | ||
508 | * clock ratio): | ||
509 | * - SRCADDR may return erroneous/corrupted data | ||
510 | * - LINK and COUNT always returns valid data | ||
511 | * - it seems that HW internally updates LINK and COUNT | ||
512 | * 'atomically', this means that reading twice using the | ||
513 | * sequence LINK1->COUNT1->LINK2->COUNT2: | ||
514 | * if LINK1 == LINK2 then COUNT1 is consistent with LINK | ||
515 | * if LINK1 <> LINK2 then COUNT2 is consistent with LINK2 | ||
516 | */ | ||
517 | uint32_t link, link2, control, control2; | ||
518 | |||
519 | /* HW read sequence */ | ||
520 | link = DMACCxLINK(baddr); | ||
521 | control = DMACCxCONTROL(baddr); | ||
522 | link2 = DMACCxLINK(baddr); | ||
523 | control2 = DMACCxCONTROL(baddr); | ||
524 | |||
525 | if (link != link2) { | ||
526 | link = link2; | ||
527 | control = control2; | ||
528 | } | ||
529 | |||
530 | count = control & DMACCxCONTROL_COUNT_MSK; /* HW count */ | ||
531 | |||
532 | cur_task = ch->tasks_done; | ||
533 | |||
534 | /* In QUEUE_LINK mode, when the task has just finished and is | ||
535 | * waiting to enter the interrupt handler, the readed HW data | ||
536 | * may correspont to the next linked task. Check it and update | ||
537 | * real cur_task accordly. | ||
538 | */ | ||
539 | struct dmac_lli *next_start_lli = LNK2LLI( | ||
540 | dmac_ch_tsk_by_idx(ch, cur_task)->end_lli->link); | ||
541 | if (next_start_lli && (next_start_lli->link == link)) | ||
542 | cur_task++; | ||
543 | |||
544 | tsk = dmac_ch_tsk_by_idx(ch, cur_task); | ||
545 | |||
546 | /* get previous to next LLI in the circular buffer */ | ||
547 | cur_lli = (link) ? ch->llibuf + (ch->llibuf_mask & | ||
548 | (LNK2LLI(link) - ch->llibuf - 1)) : tsk->end_lli; | ||
549 | |||
550 | /* Calculate current address, choose destination address when | ||
551 | * dest increment is set (usually MEMMEM or PERIMEM transfers), | ||
552 | * otherwise use source address (usually MEMPERI transfers). | ||
553 | */ | ||
554 | void *start_addr; | ||
555 | if (ch->control & (1 << DMACCxCONTROL_DI_POS)) { | ||
556 | cur_addr = cur_lli->dstaddr; | ||
557 | start_addr = tsk->start_lli->dstaddr; | ||
558 | } | ||
559 | else { | ||
560 | cur_addr = cur_lli->srcaddr; | ||
561 | start_addr = tsk->start_lli->srcaddr; | ||
562 | } | ||
563 | cur_addr += (LLI_COUNT(cur_lli) - count) << ch->cfg->swidth; | ||
564 | |||
565 | /* calculate bytes for current task */ | ||
566 | count = tsk->size - (cur_addr - start_addr); | ||
567 | |||
568 | /* count bytes for the remaining tasks */ | ||
569 | if (t_bytes) | ||
570 | while (++cur_task != ch->tasks_queued) | ||
571 | t_count += dmac_ch_tsk_by_idx(ch, cur_task)->size; | ||
572 | } | ||
573 | |||
574 | restore_irq(flags); | ||
575 | |||
576 | if (bytes) *bytes = count; | ||
577 | if (t_bytes) *t_bytes = count + t_count; | ||
578 | |||
579 | return cur_addr; | ||
580 | } | ||