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Merge commit 'v2.6.34-rc5' into oprofile/core
[deliverable/linux.git] / arch / arm / plat-mxc / dma-mx1-mx2.c
CommitLineData
58a85f46
SH		 1/*
2 * linux/arch/arm/plat-mxc/dma-mx1-mx2.c
3 *
4 * i.MX DMA registration and IRQ dispatching
5 *
6 * Copyright 2006 Pavel Pisa <pisa@cmp.felk.cvut.cz>
7 * Copyright 2008 Juergen Beisert, <kernel@pengutronix.de>
8 * Copyright 2008 Sascha Hauer, <s.hauer@pengutronix.de>
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version 2
13 * of the License, or (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
22 * MA 02110-1301, USA.
23 */
24
25#include <linux/module.h>
26#include <linux/init.h>
27#include <linux/kernel.h>
28#include <linux/interrupt.h>
29#include <linux/errno.h>
30#include <linux/clk.h>
31#include <linux/scatterlist.h>
32#include <linux/io.h>
33
34#include <asm/system.h>
35#include <asm/irq.h>
36#include <mach/hardware.h>
58a85f46
SH		 37#include <mach/dma-mx1-mx2.h>
38
39#define DMA_DCR 0x00 /* Control Register */
40#define DMA_DISR 0x04 /* Interrupt status Register */
41#define DMA_DIMR 0x08 /* Interrupt mask Register */
42#define DMA_DBTOSR 0x0c /* Burst timeout status Register */
43#define DMA_DRTOSR 0x10 /* Request timeout Register */
44#define DMA_DSESR 0x14 /* Transfer Error Status Register */
45#define DMA_DBOSR 0x18 /* Buffer overflow status Register */
46#define DMA_DBTOCR 0x1c /* Burst timeout control Register */
47#define DMA_WSRA 0x40 /* W-Size Register A */
48#define DMA_XSRA 0x44 /* X-Size Register A */
49#define DMA_YSRA 0x48 /* Y-Size Register A */
50#define DMA_WSRB 0x4c /* W-Size Register B */
51#define DMA_XSRB 0x50 /* X-Size Register B */
52#define DMA_YSRB 0x54 /* Y-Size Register B */
53#define DMA_SAR(x) (0x80 + ((x) << 6)) /* Source Address Registers */
54#define DMA_DAR(x) (0x84 + ((x) << 6)) /* Destination Address Registers */
55#define DMA_CNTR(x) (0x88 + ((x) << 6)) /* Count Registers */
56#define DMA_CCR(x) (0x8c + ((x) << 6)) /* Control Registers */
57#define DMA_RSSR(x) (0x90 + ((x) << 6)) /* Request source select Registers */
58#define DMA_BLR(x) (0x94 + ((x) << 6)) /* Burst length Registers */
59#define DMA_RTOR(x) (0x98 + ((x) << 6)) /* Request timeout Registers */
60#define DMA_BUCR(x) (0x98 + ((x) << 6)) /* Bus Utilization Registers */
61#define DMA_CCNR(x) (0x9C + ((x) << 6)) /* Channel counter Registers */
62
63#define DCR_DRST (1<<1)
64#define DCR_DEN (1<<0)
65#define DBTOCR_EN (1<<15)
66#define DBTOCR_CNT(x) ((x) & 0x7fff)
67#define CNTR_CNT(x) ((x) & 0xffffff)
68#define CCR_ACRPT (1<<14)
69#define CCR_DMOD_LINEAR (0x0 << 12)
70#define CCR_DMOD_2D (0x1 << 12)
71#define CCR_DMOD_FIFO (0x2 << 12)
72#define CCR_DMOD_EOBFIFO (0x3 << 12)
73#define CCR_SMOD_LINEAR (0x0 << 10)
74#define CCR_SMOD_2D (0x1 << 10)
75#define CCR_SMOD_FIFO (0x2 << 10)
76#define CCR_SMOD_EOBFIFO (0x3 << 10)
77#define CCR_MDIR_DEC (1<<9)
78#define CCR_MSEL_B (1<<8)
79#define CCR_DSIZ_32 (0x0 << 6)
80#define CCR_DSIZ_8 (0x1 << 6)
81#define CCR_DSIZ_16 (0x2 << 6)
82#define CCR_SSIZ_32 (0x0 << 4)
83#define CCR_SSIZ_8 (0x1 << 4)
84#define CCR_SSIZ_16 (0x2 << 4)
85#define CCR_REN (1<<3)
86#define CCR_RPT (1<<2)
87#define CCR_FRC (1<<1)
88#define CCR_CEN (1<<0)
89#define RTOR_EN (1<<15)
90#define RTOR_CLK (1<<14)
91#define RTOR_PSC (1<<13)
92
93/*
94 * struct imx_dma_channel - i.MX specific DMA extension
95 * @name: name specified by DMA client
96 * @irq_handler: client callback for end of transfer
97 * @err_handler: client callback for error condition
98 * @data: clients context data for callbacks
99 * @dma_mode: direction of the transfer %DMA_MODE_READ or %DMA_MODE_WRITE
100 * @sg: pointer to the actual read/written chunk for scatter-gather emulation
101 * @resbytes: total residual number of bytes to transfer
102 * (it can be lower or same as sum of SG mapped chunk sizes)
103 * @sgcount: number of chunks to be read/written
104 *
105 * Structure is used for IMX DMA processing. It would be probably good
106 * @struct dma_struct in the future for external interfacing and use
107 * @struct imx_dma_channel only as extension to it.
108 */
109
110struct imx_dma_channel {
111 const char *name;
112 void (*irq_handler) (int, void *);
113 void (*err_handler) (int, void *, int errcode);
114 void (*prog_handler) (int, void *, struct scatterlist *);
115 void *data;
4e57ea9a 116 unsigned int dma_mode;
58a85f46
SH		 117 struct scatterlist *sg;
118 unsigned int resbytes;
119 int dma_num;
120
121 int in_use;
122
123 u32 ccr_from_device;
124 u32 ccr_to_device;
125
126 struct timer_list watchdog;
127
128 int hw_chaining;
129};
130
e9f49d41
UKK		 131static void __iomem *imx_dmav1_baseaddr;
132
133static void imx_dmav1_writel(unsigned val, unsigned offset)
134{
135 __raw_writel(val, imx_dmav1_baseaddr + offset);
136}
137
138static unsigned imx_dmav1_readl(unsigned offset)
139{
140 return __raw_readl(imx_dmav1_baseaddr + offset);
141}
142
58a85f46
SH		 143static struct imx_dma_channel imx_dma_channels[IMX_DMA_CHANNELS];
144
145static struct clk *dma_clk;
146
147static int imx_dma_hw_chain(struct imx_dma_channel *imxdma)
148{
149 if (cpu_is_mx27())
150 return imxdma->hw_chaining;
151 else
152 return 0;
153}
154
58a85f46
SH		 155/*
156 * imx_dma_sg_next - prepare next chunk for scatter-gather DMA emulation
157 */
158static inline int imx_dma_sg_next(int channel, struct scatterlist *sg)
159{
160 struct imx_dma_channel *imxdma = &imx_dma_channels[channel];
161 unsigned long now;
162
163 if (!imxdma->name) {
164 printk(KERN_CRIT "%s: called for not allocated channel %d\n",
165 __func__, channel);
166 return 0;
167 }
168
169 now = min(imxdma->resbytes, sg->length);
4998f1a3
SH		 170 if (imxdma->resbytes != IMX_DMA_LENGTH_LOOP)
171 imxdma->resbytes -= now;
58a85f46
SH		 172
173 if ((imxdma->dma_mode & DMA_MODE_MASK) == DMA_MODE_READ)
e9f49d41 174 imx_dmav1_writel(sg->dma_address, DMA_DAR(channel));
58a85f46 175 else
e9f49d41 176 imx_dmav1_writel(sg->dma_address, DMA_SAR(channel));
58a85f46 177
e9f49d41 178 imx_dmav1_writel(now, DMA_CNTR(channel));
58a85f46
SH		 179
180 pr_debug("imxdma%d: next sg chunk dst 0x%08x, src 0x%08x, "
181 "size 0x%08x\n", channel,
e9f49d41
UKK		 182 imx_dmav1_readl(DMA_DAR(channel)),
183 imx_dmav1_readl(DMA_SAR(channel)),
184 imx_dmav1_readl(DMA_CNTR(channel)));
58a85f46
SH		 185
186 return now;
187}
188
189/**
190 * imx_dma_setup_single - setup i.MX DMA channel for linear memory to/from
191 * device transfer
192 *
193 * @channel: i.MX DMA channel number
194 * @dma_address: the DMA/physical memory address of the linear data block
195 * to transfer
196 * @dma_length: length of the data block in bytes
197 * @dev_addr: physical device port address
198 * @dmamode: DMA transfer mode, %DMA_MODE_READ from the device to the memory
199 * or %DMA_MODE_WRITE from memory to the device
200 *
201 * Return value: if incorrect parameters are provided -%EINVAL.
202 * Zero indicates success.
203 */
204int
205imx_dma_setup_single(int channel, dma_addr_t dma_address,
206 unsigned int dma_length, unsigned int dev_addr,
33ebc19d 207 unsigned int dmamode)
58a85f46
SH		 208{
209 struct imx_dma_channel *imxdma = &imx_dma_channels[channel];
210
211 imxdma->sg = NULL;
212 imxdma->dma_mode = dmamode;
213
214 if (!dma_address) {
215 printk(KERN_ERR "imxdma%d: imx_dma_setup_single null address\n",
216 channel);
217 return -EINVAL;
218 }
219
220 if (!dma_length) {
221 printk(KERN_ERR "imxdma%d: imx_dma_setup_single zero length\n",
222 channel);
223 return -EINVAL;
224 }
225
226 if ((dmamode & DMA_MODE_MASK) == DMA_MODE_READ) {
227 pr_debug("imxdma%d: %s dma_addressg=0x%08x dma_length=%d "
228 "dev_addr=0x%08x for read\n",
229 channel, __func__, (unsigned int)dma_address,
230 dma_length, dev_addr);
231
e9f49d41
UKK		 232 imx_dmav1_writel(dev_addr, DMA_SAR(channel));
233 imx_dmav1_writel(dma_address, DMA_DAR(channel));
234 imx_dmav1_writel(imxdma->ccr_from_device, DMA_CCR(channel));
58a85f46
SH		 235 } else if ((dmamode & DMA_MODE_MASK) == DMA_MODE_WRITE) {
236 pr_debug("imxdma%d: %s dma_addressg=0x%08x dma_length=%d "
237 "dev_addr=0x%08x for write\n",
238 channel, __func__, (unsigned int)dma_address,
239 dma_length, dev_addr);
240
e9f49d41
UKK		 241 imx_dmav1_writel(dma_address, DMA_SAR(channel));
242 imx_dmav1_writel(dev_addr, DMA_DAR(channel));
243 imx_dmav1_writel(imxdma->ccr_to_device,
244 DMA_CCR(channel));
58a85f46
SH		 245 } else {
246 printk(KERN_ERR "imxdma%d: imx_dma_setup_single bad dmamode\n",
247 channel);
248 return -EINVAL;
249 }
250
e9f49d41 251 imx_dmav1_writel(dma_length, DMA_CNTR(channel));
58a85f46
SH		 252
253 return 0;
254}
255EXPORT_SYMBOL(imx_dma_setup_single);
256
257/**
258 * imx_dma_setup_sg - setup i.MX DMA channel SG list to/from device transfer
259 * @channel: i.MX DMA channel number
260 * @sg: pointer to the scatter-gather list/vector
261 * @sgcount: scatter-gather list hungs count
262 * @dma_length: total length of the transfer request in bytes
263 * @dev_addr: physical device port address
264 * @dmamode: DMA transfer mode, %DMA_MODE_READ from the device to the memory
265 * or %DMA_MODE_WRITE from memory to the device
266 *
267 * The function sets up DMA channel state and registers to be ready for
268 * transfer specified by provided parameters. The scatter-gather emulation
269 * is set up according to the parameters.
270 *
271 * The full preparation of the transfer requires setup of more register
272 * by the caller before imx_dma_enable() can be called.
273 *
274 * %BLR(channel) holds transfer burst length in bytes, 0 means 64 bytes
275 *
276 * %RSSR(channel) has to be set to the DMA request line source %DMA_REQ_xxx
277 *
278 * %CCR(channel) has to specify transfer parameters, the next settings is
279 * typical for linear or simple scatter-gather transfers if %DMA_MODE_READ is
280 * specified
281 *
282 * %CCR_DMOD_LINEAR | %CCR_DSIZ_32 | %CCR_SMOD_FIFO | %CCR_SSIZ_x
283 *
284 * The typical setup for %DMA_MODE_WRITE is specified by next options
285 * combination
286 *
287 * %CCR_SMOD_LINEAR | %CCR_SSIZ_32 | %CCR_DMOD_FIFO | %CCR_DSIZ_x
288 *
289 * Be careful here and do not mistakenly mix source and target device
290 * port sizes constants, they are really different:
291 * %CCR_SSIZ_8, %CCR_SSIZ_16, %CCR_SSIZ_32,
292 * %CCR_DSIZ_8, %CCR_DSIZ_16, %CCR_DSIZ_32
293 *
294 * Return value: if incorrect parameters are provided -%EINVAL.
295 * Zero indicates success.
296 */
297int
298imx_dma_setup_sg(int channel,
299 struct scatterlist *sg, unsigned int sgcount,
300 unsigned int dma_length, unsigned int dev_addr,
33ebc19d 301 unsigned int dmamode)
58a85f46
SH		 302{
303 struct imx_dma_channel *imxdma = &imx_dma_channels[channel];
304
305 if (imxdma->in_use)
306 return -EBUSY;
307
308 imxdma->sg = sg;
309 imxdma->dma_mode = dmamode;
310 imxdma->resbytes = dma_length;
311
312 if (!sg || !sgcount) {
313 printk(KERN_ERR "imxdma%d: imx_dma_setup_sg epty sg list\n",
314 channel);
315 return -EINVAL;
316 }
317
318 if (!sg->length) {
319 printk(KERN_ERR "imxdma%d: imx_dma_setup_sg zero length\n",
320 channel);
321 return -EINVAL;
322 }
323
324 if ((dmamode & DMA_MODE_MASK) == DMA_MODE_READ) {
325 pr_debug("imxdma%d: %s sg=%p sgcount=%d total length=%d "
326 "dev_addr=0x%08x for read\n",
327 channel, __func__, sg, sgcount, dma_length, dev_addr);
328
e9f49d41
UKK		 329 imx_dmav1_writel(dev_addr, DMA_SAR(channel));
330 imx_dmav1_writel(imxdma->ccr_from_device, DMA_CCR(channel));
58a85f46
SH		 331 } else if ((dmamode & DMA_MODE_MASK) == DMA_MODE_WRITE) {
332 pr_debug("imxdma%d: %s sg=%p sgcount=%d total length=%d "
333 "dev_addr=0x%08x for write\n",
334 channel, __func__, sg, sgcount, dma_length, dev_addr);
335
e9f49d41
UKK		 336 imx_dmav1_writel(dev_addr, DMA_DAR(channel));
337 imx_dmav1_writel(imxdma->ccr_to_device, DMA_CCR(channel));
58a85f46
SH		 338 } else {
339 printk(KERN_ERR "imxdma%d: imx_dma_setup_sg bad dmamode\n",
340 channel);
341 return -EINVAL;
342 }
343
344 imx_dma_sg_next(channel, sg);
345
346 return 0;
347}
348EXPORT_SYMBOL(imx_dma_setup_sg);
349
350int
351imx_dma_config_channel(int channel, unsigned int config_port,
352 unsigned int config_mem, unsigned int dmareq, int hw_chaining)
353{
354 struct imx_dma_channel *imxdma = &imx_dma_channels[channel];
355 u32 dreq = 0;
356
357 imxdma->hw_chaining = 0;
358
359 if (hw_chaining) {
360 imxdma->hw_chaining = 1;
361 if (!imx_dma_hw_chain(imxdma))
362 return -EINVAL;
363 }
364
365 if (dmareq)
366 dreq = CCR_REN;
367
368 imxdma->ccr_from_device = config_port | (config_mem << 2) | dreq;
369 imxdma->ccr_to_device = config_mem | (config_port << 2) | dreq;
370
e9f49d41 371 imx_dmav1_writel(dmareq, DMA_RSSR(channel));
58a85f46
SH		 372
373 return 0;
374}
375EXPORT_SYMBOL(imx_dma_config_channel);
376
377void imx_dma_config_burstlen(int channel, unsigned int burstlen)
378{
e9f49d41 379 imx_dmav1_writel(burstlen, DMA_BLR(channel));
58a85f46
SH		 380}
381EXPORT_SYMBOL(imx_dma_config_burstlen);
382
383/**
384 * imx_dma_setup_handlers - setup i.MX DMA channel end and error notification
385 * handlers
386 * @channel: i.MX DMA channel number
387 * @irq_handler: the pointer to the function called if the transfer
388 * ends successfully
389 * @err_handler: the pointer to the function called if the premature
390 * end caused by error occurs
391 * @data: user specified value to be passed to the handlers
392 */
393int
394imx_dma_setup_handlers(int channel,
395 void (*irq_handler) (int, void *),
396 void (*err_handler) (int, void *, int),
397 void *data)
398{
399 struct imx_dma_channel *imxdma = &imx_dma_channels[channel];
400 unsigned long flags;
401
402 if (!imxdma->name) {
403 printk(KERN_CRIT "%s: called for not allocated channel %d\n",
404 __func__, channel);
405 return -ENODEV;
406 }
407
408 local_irq_save(flags);
e9f49d41 409 imx_dmav1_writel(1 << channel, DMA_DISR);
58a85f46
SH		 410 imxdma->irq_handler = irq_handler;
411 imxdma->err_handler = err_handler;
412 imxdma->data = data;
413 local_irq_restore(flags);
414 return 0;
415}
416EXPORT_SYMBOL(imx_dma_setup_handlers);
417
418/**
419 * imx_dma_setup_progression_handler - setup i.MX DMA channel progression
420 * handlers
421 * @channel: i.MX DMA channel number
422 * @prog_handler: the pointer to the function called if the transfer progresses
423 */
424int
425imx_dma_setup_progression_handler(int channel,
426 void (*prog_handler) (int, void*, struct scatterlist*))
427{
428 struct imx_dma_channel *imxdma = &imx_dma_channels[channel];
429 unsigned long flags;
430
431 if (!imxdma->name) {
432 printk(KERN_CRIT "%s: called for not allocated channel %d\n",
433 __func__, channel);
434 return -ENODEV;
435 }
436
437 local_irq_save(flags);
438 imxdma->prog_handler = prog_handler;
439 local_irq_restore(flags);
440 return 0;
441}
442EXPORT_SYMBOL(imx_dma_setup_progression_handler);
443
444/**
445 * imx_dma_enable - function to start i.MX DMA channel operation
446 * @channel: i.MX DMA channel number
447 *
448 * The channel has to be allocated by driver through imx_dma_request()
449 * or imx_dma_request_by_prio() function.
450 * The transfer parameters has to be set to the channel registers through
451 * call of the imx_dma_setup_single() or imx_dma_setup_sg() function
452 * and registers %BLR(channel), %RSSR(channel) and %CCR(channel) has to
453 * be set prior this function call by the channel user.
454 */
455void imx_dma_enable(int channel)
456{
457 struct imx_dma_channel *imxdma = &imx_dma_channels[channel];
458 unsigned long flags;
459
460 pr_debug("imxdma%d: imx_dma_enable\n", channel);
461
462 if (!imxdma->name) {
463 printk(KERN_CRIT "%s: called for not allocated channel %d\n",
464 __func__, channel);
465 return;
466 }
467
468 if (imxdma->in_use)
469 return;
470
471 local_irq_save(flags);
472
e9f49d41
UKK		 473 imx_dmav1_writel(1 << channel, DMA_DISR);
474 imx_dmav1_writel(imx_dmav1_readl(DMA_DIMR) & ~(1 << channel), DMA_DIMR);
475 imx_dmav1_writel(imx_dmav1_readl(DMA_CCR(channel)) | CCR_CEN |
476 CCR_ACRPT, DMA_CCR(channel));
58a85f46
SH		 477
478#ifdef CONFIG_ARCH_MX2
8735fde2
UKK		 479 if ((cpu_is_mx21() || cpu_is_mx27()) &&
480 imxdma->sg && imx_dma_hw_chain(imxdma)) {
58a85f46
SH		 481 imxdma->sg = sg_next(imxdma->sg);
482 if (imxdma->sg) {
483 u32 tmp;
484 imx_dma_sg_next(channel, imxdma->sg);
e9f49d41
UKK		 485 tmp = imx_dmav1_readl(DMA_CCR(channel));
486 imx_dmav1_writel(tmp | CCR_RPT | CCR_ACRPT,
487 DMA_CCR(channel));
58a85f46
SH		 488 }
489 }
490#endif
491 imxdma->in_use = 1;
492
493 local_irq_restore(flags);
494}
495EXPORT_SYMBOL(imx_dma_enable);
496
497/**
498 * imx_dma_disable - stop, finish i.MX DMA channel operatin
499 * @channel: i.MX DMA channel number
500 */
501void imx_dma_disable(int channel)
502{
503 struct imx_dma_channel *imxdma = &imx_dma_channels[channel];
504 unsigned long flags;
505
506 pr_debug("imxdma%d: imx_dma_disable\n", channel);
507
508 if (imx_dma_hw_chain(imxdma))
509 del_timer(&imxdma->watchdog);
510
511 local_irq_save(flags);
e9f49d41
UKK		 512 imx_dmav1_writel(imx_dmav1_readl(DMA_DIMR) | (1 << channel), DMA_DIMR);
513 imx_dmav1_writel(imx_dmav1_readl(DMA_CCR(channel)) & ~CCR_CEN,
514 DMA_CCR(channel));
515 imx_dmav1_writel(1 << channel, DMA_DISR);
58a85f46
SH		 516 imxdma->in_use = 0;
517 local_irq_restore(flags);
518}
519EXPORT_SYMBOL(imx_dma_disable);
520
7c995023 521#ifdef CONFIG_ARCH_MX2
58a85f46
SH		 522static void imx_dma_watchdog(unsigned long chno)
523{
524 struct imx_dma_channel *imxdma = &imx_dma_channels[chno];
525
e9f49d41 526 imx_dmav1_writel(0, DMA_CCR(chno));
58a85f46
SH		 527 imxdma->in_use = 0;
528 imxdma->sg = NULL;
529
530 if (imxdma->err_handler)
531 imxdma->err_handler(chno, imxdma->data, IMX_DMA_ERR_TIMEOUT);
532}
7c995023 533#endif
58a85f46
SH		 534
535static irqreturn_t dma_err_handler(int irq, void *dev_id)
536{
537 int i, disr;
538 struct imx_dma_channel *imxdma;
539 unsigned int err_mask;
540 int errcode;
541
e9f49d41 542 disr = imx_dmav1_readl(DMA_DISR);
58a85f46 543
e9f49d41
UKK		 544 err_mask = imx_dmav1_readl(DMA_DBTOSR) |
545 imx_dmav1_readl(DMA_DRTOSR) |
546 imx_dmav1_readl(DMA_DSESR) |
547 imx_dmav1_readl(DMA_DBOSR);
58a85f46
SH		 548
549 if (!err_mask)
550 return IRQ_HANDLED;
551
e9f49d41 552 imx_dmav1_writel(disr & err_mask, DMA_DISR);
58a85f46
SH		 553
554 for (i = 0; i < IMX_DMA_CHANNELS; i++) {
555 if (!(err_mask & (1 << i)))
556 continue;
557 imxdma = &imx_dma_channels[i];
558 errcode = 0;
559
e9f49d41
UKK		 560 if (imx_dmav1_readl(DMA_DBTOSR) & (1 << i)) {
561 imx_dmav1_writel(1 << i, DMA_DBTOSR);
58a85f46
SH		 562 errcode |= IMX_DMA_ERR_BURST;
563 }
e9f49d41
UKK		 564 if (imx_dmav1_readl(DMA_DRTOSR) & (1 << i)) {
565 imx_dmav1_writel(1 << i, DMA_DRTOSR);
58a85f46
SH		 566 errcode |= IMX_DMA_ERR_REQUEST;
567 }
e9f49d41
UKK		 568 if (imx_dmav1_readl(DMA_DSESR) & (1 << i)) {
569 imx_dmav1_writel(1 << i, DMA_DSESR);
58a85f46
SH		 570 errcode |= IMX_DMA_ERR_TRANSFER;
571 }
e9f49d41
UKK		 572 if (imx_dmav1_readl(DMA_DBOSR) & (1 << i)) {
573 imx_dmav1_writel(1 << i, DMA_DBOSR);
58a85f46
SH		 574 errcode |= IMX_DMA_ERR_BUFFER;
575 }
576 if (imxdma->name && imxdma->err_handler) {
577 imxdma->err_handler(i, imxdma->data, errcode);
578 continue;
579 }
580
581 imx_dma_channels[i].sg = NULL;
582
583 printk(KERN_WARNING
584 "DMA timeout on channel %d (%s) -%s%s%s%s\n",
585 i, imxdma->name,
586 errcode & IMX_DMA_ERR_BURST ? " burst" : "",
587 errcode & IMX_DMA_ERR_REQUEST ? " request" : "",
588 errcode & IMX_DMA_ERR_TRANSFER ? " transfer" : "",
589 errcode & IMX_DMA_ERR_BUFFER ? " buffer" : "");
590 }
591 return IRQ_HANDLED;
592}
593
594static void dma_irq_handle_channel(int chno)
595{
596 struct imx_dma_channel *imxdma = &imx_dma_channels[chno];
597
598 if (!imxdma->name) {
599 /*
600 * IRQ for an unregistered DMA channel:
601 * let's clear the interrupts and disable it.
602 */
603 printk(KERN_WARNING
604 "spurious IRQ for DMA channel %d\n", chno);
605 return;
606 }
607
608 if (imxdma->sg) {
609 u32 tmp;
610 struct scatterlist *current_sg = imxdma->sg;
611 imxdma->sg = sg_next(imxdma->sg);
612
613 if (imxdma->sg) {
614 imx_dma_sg_next(chno, imxdma->sg);
615
e9f49d41 616 tmp = imx_dmav1_readl(DMA_CCR(chno));
58a85f46
SH		 617
618 if (imx_dma_hw_chain(imxdma)) {
619 /* FIXME: The timeout should probably be
620 * configurable
621 */
622 mod_timer(&imxdma->watchdog,
623 jiffies + msecs_to_jiffies(500));
624
625 tmp |= CCR_CEN | CCR_RPT | CCR_ACRPT;
e9f49d41 626 imx_dmav1_writel(tmp, DMA_CCR(chno));
58a85f46 627 } else {
e9f49d41 628 imx_dmav1_writel(tmp & ~CCR_CEN, DMA_CCR(chno));
58a85f46
SH		 629 tmp |= CCR_CEN;
630 }
631
e9f49d41 632 imx_dmav1_writel(tmp, DMA_CCR(chno));
58a85f46
SH		 633
634 if (imxdma->prog_handler)
635 imxdma->prog_handler(chno, imxdma->data,
636 current_sg);
637
638 return;
639 }
640
641 if (imx_dma_hw_chain(imxdma)) {
642 del_timer(&imxdma->watchdog);
643 return;
644 }
645 }
646
e9f49d41 647 imx_dmav1_writel(0, DMA_CCR(chno));
58a85f46
SH		 648 imxdma->in_use = 0;
649 if (imxdma->irq_handler)
650 imxdma->irq_handler(chno, imxdma->data);
651}
652
653static irqreturn_t dma_irq_handler(int irq, void *dev_id)
654{
655 int i, disr;
656
657#ifdef CONFIG_ARCH_MX2
8735fde2
UKK		 658 if (cpu_is_mx21() || cpu_is_mx27())
659 dma_err_handler(irq, dev_id);
58a85f46
SH		 660#endif
661
e9f49d41 662 disr = imx_dmav1_readl(DMA_DISR);
58a85f46
SH		 663
664 pr_debug("imxdma: dma_irq_handler called, disr=0x%08x\n",
665 disr);
666
e9f49d41 667 imx_dmav1_writel(disr, DMA_DISR);
58a85f46
SH		 668 for (i = 0; i < IMX_DMA_CHANNELS; i++) {
669 if (disr & (1 << i))
670 dma_irq_handle_channel(i);
671 }
672
673 return IRQ_HANDLED;
674}
675
676/**
677 * imx_dma_request - request/allocate specified channel number
678 * @channel: i.MX DMA channel number
679 * @name: the driver/caller own non-%NULL identification
680 */
681int imx_dma_request(int channel, const char *name)
682{
683 struct imx_dma_channel *imxdma = &imx_dma_channels[channel];
684 unsigned long flags;
7c995023 685 int ret = 0;
58a85f46
SH		 686
687 /* basic sanity checks */
688 if (!name)
689 return -EINVAL;
690
691 if (channel >= IMX_DMA_CHANNELS) {
692 printk(KERN_CRIT "%s: called for non-existed channel %d\n",
693 __func__, channel);
694 return -EINVAL;
695 }
696
697 local_irq_save(flags);
698 if (imxdma->name) {
699 local_irq_restore(flags);
700 return -EBUSY;
701 }
f2292532
MF		 702 memset(imxdma, 0, sizeof(imxdma));
703 imxdma->name = name;
704 local_irq_restore(flags); /* request_irq() can block */
58a85f46
SH		 705
706#ifdef CONFIG_ARCH_MX2
8735fde2
UKK		 707 if (cpu_is_mx21() || cpu_is_mx27()) {
708 ret = request_irq(MX2x_INT_DMACH0 + channel,
709 dma_irq_handler, 0, "DMA", NULL);
710 if (ret) {
711 imxdma->name = NULL;
712 pr_crit("Can't register IRQ %d for DMA channel %d\n",
713 MX2x_INT_DMACH0 + channel, channel);
714 return ret;
715 }
716 init_timer(&imxdma->watchdog);
717 imxdma->watchdog.function = &imx_dma_watchdog;
718 imxdma->watchdog.data = channel;
58a85f46 719 }
58a85f46
SH		 720#endif
721
7c995023 722 return ret;
58a85f46
SH		 723}
724EXPORT_SYMBOL(imx_dma_request);
725
726/**
727 * imx_dma_free - release previously acquired channel
728 * @channel: i.MX DMA channel number
729 */
730void imx_dma_free(int channel)
731{
732 unsigned long flags;
733 struct imx_dma_channel *imxdma = &imx_dma_channels[channel];
734
735 if (!imxdma->name) {
736 printk(KERN_CRIT
737 "%s: trying to free free channel %d\n",
738 __func__, channel);
739 return;
740 }
741
742 local_irq_save(flags);
743 /* Disable interrupts */
de0096d8 744 imx_dma_disable(channel);
58a85f46
SH		 745 imxdma->name = NULL;
746
747#ifdef CONFIG_ARCH_MX2
8735fde2
UKK		 748 if (cpu_is_mx21() || cpu_is_mx27())
749 free_irq(MX2x_INT_DMACH0 + channel, NULL);
58a85f46
SH		 750#endif
751
752 local_irq_restore(flags);
753}
754EXPORT_SYMBOL(imx_dma_free);
755
756/**
757 * imx_dma_request_by_prio - find and request some of free channels best
758 * suiting requested priority
759 * @channel: i.MX DMA channel number
760 * @name: the driver/caller own non-%NULL identification
761 *
762 * This function tries to find a free channel in the specified priority group
763 * This function tries to find a free channel in the specified priority group
764 * if the priority cannot be achieved it tries to look for free channel
765 * in the higher and then even lower priority groups.
766 *
767 * Return value: If there is no free channel to allocate, -%ENODEV is returned.
768 * On successful allocation channel is returned.
769 */
770int imx_dma_request_by_prio(const char *name, enum imx_dma_prio prio)
771{
772 int i;
773 int best;
774
775 switch (prio) {
776 case (DMA_PRIO_HIGH):
777 best = 8;
778 break;
779 case (DMA_PRIO_MEDIUM):
780 best = 4;
781 break;
782 case (DMA_PRIO_LOW):
783 default:
784 best = 0;
785 break;
786 }
787
788 for (i = best; i < IMX_DMA_CHANNELS; i++)
789 if (!imx_dma_request(i, name))
790 return i;
791
792 for (i = best - 1; i >= 0; i--)
793 if (!imx_dma_request(i, name))
794 return i;
795
796 printk(KERN_ERR "%s: no free DMA channel found\n", __func__);
797
798 return -ENODEV;
799}
800EXPORT_SYMBOL(imx_dma_request_by_prio);
801
802static int __init imx_dma_init(void)
803{
804 int ret = 0;
805 int i;
806
e9f49d41
UKK		 807#ifdef CONFIG_ARCH_MX1
808 if (cpu_is_mx1())
809 imx_dmav1_baseaddr = MX1_IO_ADDRESS(MX1_DMA_BASE_ADDR);
810 else
811#endif
812#ifdef CONFIG_MACH_MX21
813 if (cpu_is_mx21())
814 imx_dmav1_baseaddr = MX21_IO_ADDRESS(MX21_DMA_BASE_ADDR);
815 else
816#endif
817#ifdef CONFIG_MACH_MX27
818 if (cpu_is_mx27())
819 imx_dmav1_baseaddr = MX27_IO_ADDRESS(MX27_DMA_BASE_ADDR);
820 else
821#endif
822 BUG();
823
e65fb009 824 dma_clk = clk_get(NULL, "dma");
58a85f46
SH		 825 clk_enable(dma_clk);
826
827 /* reset DMA module */
e9f49d41 828 imx_dmav1_writel(DCR_DRST, DMA_DCR);
58a85f46
SH		 829
830#ifdef CONFIG_ARCH_MX1
8735fde2
UKK		 831 if (cpu_is_mx1()) {
832 ret = request_irq(MX1_DMA_INT, dma_irq_handler, 0, "DMA", NULL);
833 if (ret) {
834 pr_crit("Wow! Can't register IRQ for DMA\n");
835 return ret;
836 }
58a85f46 837
8735fde2
UKK		 838 ret = request_irq(MX1_DMA_ERR, dma_err_handler, 0, "DMA", NULL);
839 if (ret) {
840 pr_crit("Wow! Can't register ERRIRQ for DMA\n");
841 free_irq(MX1_DMA_INT, NULL);
842 return ret;
843 }
58a85f46
SH		 844 }
845#endif
846 /* enable DMA module */
e9f49d41 847 imx_dmav1_writel(DCR_DEN, DMA_DCR);
58a85f46
SH		 848
849 /* clear all interrupts */
e9f49d41 850 imx_dmav1_writel((1 << IMX_DMA_CHANNELS) - 1, DMA_DISR);
58a85f46
SH		 851
852 /* disable interrupts */
e9f49d41 853 imx_dmav1_writel((1 << IMX_DMA_CHANNELS) - 1, DMA_DIMR);
58a85f46
SH		 854
855 for (i = 0; i < IMX_DMA_CHANNELS; i++) {
856 imx_dma_channels[i].sg = NULL;
857 imx_dma_channels[i].dma_num = i;
858 }
859
860 return ret;
861}
862
863arch_initcall(imx_dma_init);
Linux kernel - Deliverables
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