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s390/numa: always use logical cpu and core ids
[linux-2.6/btrfs-unstable.git] / drivers / dma / imx-sdma.c
blobb9629b2bfc050b3c6cd4db691da49f99c7d85232
1 /*
2 * drivers/dma/imx-sdma.c
3 *
4 * This file contains a driver for the Freescale Smart DMA engine
5 *
6 * Copyright 2010 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
7 *
8 * Based on code from Freescale:
9 *
10 * Copyright 2004-2009 Freescale Semiconductor, Inc. All Rights Reserved.
11 *
12 * The code contained herein is licensed under the GNU General Public
13 * License. You may obtain a copy of the GNU General Public License
14 * Version 2 or later at the following locations:
15 *
16 * http://www.opensource.org/licenses/gpl-license.html
17 * http://www.gnu.org/copyleft/gpl.html
18 */
19
20 #include <linux/init.h>
21 #include <linux/iopoll.h>
22 #include <linux/module.h>
23 #include <linux/types.h>
24 #include <linux/bitops.h>
25 #include <linux/mm.h>
26 #include <linux/interrupt.h>
27 #include <linux/clk.h>
28 #include <linux/delay.h>
29 #include <linux/sched.h>
30 #include <linux/semaphore.h>
31 #include <linux/spinlock.h>
32 #include <linux/device.h>
33 #include <linux/dma-mapping.h>
34 #include <linux/firmware.h>
35 #include <linux/slab.h>
36 #include <linux/platform_device.h>
37 #include <linux/dmaengine.h>
38 #include <linux/of.h>
39 #include <linux/of_address.h>
40 #include <linux/of_device.h>
41 #include <linux/of_dma.h>
42
43 #include <asm/irq.h>
44 #include <linux/platform_data/dma-imx-sdma.h>
45 #include <linux/platform_data/dma-imx.h>
46 #include <linux/regmap.h>
47 #include <linux/mfd/syscon.h>
48 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
49
50 #include "dmaengine.h"
51
52 /* SDMA registers */
53 #define SDMA_H_C0PTR 0x000
54 #define SDMA_H_INTR 0x004
55 #define SDMA_H_STATSTOP 0x008
56 #define SDMA_H_START 0x00c
57 #define SDMA_H_EVTOVR 0x010
58 #define SDMA_H_DSPOVR 0x014
59 #define SDMA_H_HOSTOVR 0x018
60 #define SDMA_H_EVTPEND 0x01c
61 #define SDMA_H_DSPENBL 0x020
62 #define SDMA_H_RESET 0x024
63 #define SDMA_H_EVTERR 0x028
64 #define SDMA_H_INTRMSK 0x02c
65 #define SDMA_H_PSW 0x030
66 #define SDMA_H_EVTERRDBG 0x034
67 #define SDMA_H_CONFIG 0x038
68 #define SDMA_ONCE_ENB 0x040
69 #define SDMA_ONCE_DATA 0x044
70 #define SDMA_ONCE_INSTR 0x048
71 #define SDMA_ONCE_STAT 0x04c
72 #define SDMA_ONCE_CMD 0x050
73 #define SDMA_EVT_MIRROR 0x054
74 #define SDMA_ILLINSTADDR 0x058
75 #define SDMA_CHN0ADDR 0x05c
76 #define SDMA_ONCE_RTB 0x060
77 #define SDMA_XTRIG_CONF1 0x070
78 #define SDMA_XTRIG_CONF2 0x074
79 #define SDMA_CHNENBL0_IMX35 0x200
80 #define SDMA_CHNENBL0_IMX31 0x080
81 #define SDMA_CHNPRI_0 0x100
82
83 /*
84 * Buffer descriptor status values.
85 */
86 #define BD_DONE 0x01
87 #define BD_WRAP 0x02
88 #define BD_CONT 0x04
89 #define BD_INTR 0x08
90 #define BD_RROR 0x10
91 #define BD_LAST 0x20
92 #define BD_EXTD 0x80
93
94 /*
95 * Data Node descriptor status values.
96 */
97 #define DND_END_OF_FRAME 0x80
98 #define DND_END_OF_XFER 0x40
99 #define DND_DONE 0x20
100 #define DND_UNUSED 0x01
101
102 /*
103 * IPCV2 descriptor status values.
104 */
105 #define BD_IPCV2_END_OF_FRAME 0x40
106
107 #define IPCV2_MAX_NODES 50
108 /*
109 * Error bit set in the CCB status field by the SDMA,
110 * in setbd routine, in case of a transfer error
111 */
112 #define DATA_ERROR 0x10000000
113
114 /*
115 * Buffer descriptor commands.
116 */
117 #define C0_ADDR 0x01
118 #define C0_LOAD 0x02
119 #define C0_DUMP 0x03
120 #define C0_SETCTX 0x07
121 #define C0_GETCTX 0x03
122 #define C0_SETDM 0x01
123 #define C0_SETPM 0x04
124 #define C0_GETDM 0x02
125 #define C0_GETPM 0x08
126 /*
127 * Change endianness indicator in the BD command field
128 */
129 #define CHANGE_ENDIANNESS 0x80
130
131 /*
132 * p_2_p watermark_level description
133 * Bits Name Description
134 * 0-7 Lower WML Lower watermark level
135 * 8 PS 1: Pad Swallowing
136 * 0: No Pad Swallowing
137 * 9 PA 1: Pad Adding
138 * 0: No Pad Adding
139 * 10 SPDIF If this bit is set both source
140 * and destination are on SPBA
141 * 11 Source Bit(SP) 1: Source on SPBA
142 * 0: Source on AIPS
143 * 12 Destination Bit(DP) 1: Destination on SPBA
144 * 0: Destination on AIPS
145 * 13-15 --------- MUST BE 0
146 * 16-23 Higher WML HWML
147 * 24-27 N Total number of samples after
148 * which Pad adding/Swallowing
149 * must be done. It must be odd.
150 * 28 Lower WML Event(LWE) SDMA events reg to check for
151 * LWML event mask
152 * 0: LWE in EVENTS register
153 * 1: LWE in EVENTS2 register
154 * 29 Higher WML Event(HWE) SDMA events reg to check for
155 * HWML event mask
156 * 0: HWE in EVENTS register
157 * 1: HWE in EVENTS2 register
158 * 30 --------- MUST BE 0
159 * 31 CONT 1: Amount of samples to be
160 * transferred is unknown and
161 * script will keep on
162 * transferring samples as long as
163 * both events are detected and
164 * script must be manually stopped
165 * by the application
166 * 0: The amount of samples to be
167 * transferred is equal to the
168 * count field of mode word
169 */
170 #define SDMA_WATERMARK_LEVEL_LWML 0xFF
171 #define SDMA_WATERMARK_LEVEL_PS BIT(8)
172 #define SDMA_WATERMARK_LEVEL_PA BIT(9)
173 #define SDMA_WATERMARK_LEVEL_SPDIF BIT(10)
174 #define SDMA_WATERMARK_LEVEL_SP BIT(11)
175 #define SDMA_WATERMARK_LEVEL_DP BIT(12)
176 #define SDMA_WATERMARK_LEVEL_HWML (0xFF << 16)
177 #define SDMA_WATERMARK_LEVEL_LWE BIT(28)
178 #define SDMA_WATERMARK_LEVEL_HWE BIT(29)
179 #define SDMA_WATERMARK_LEVEL_CONT BIT(31)
180
181 /*
182 * Mode/Count of data node descriptors - IPCv2
183 */
184 struct sdma_mode_count {
185 u32 count : 16; /* size of the buffer pointed by this BD */
186 u32 status : 8; /* E,R,I,C,W,D status bits stored here */
187 u32 command : 8; /* command mostly used for channel 0 */
188 };
189
190 /*
191 * Buffer descriptor
192 */
193 struct sdma_buffer_descriptor {
194 struct sdma_mode_count mode;
195 u32 buffer_addr; /* address of the buffer described */
196 u32 ext_buffer_addr; /* extended buffer address */
197 } __attribute__ ((packed));
198
199 /**
200 * struct sdma_channel_control - Channel control Block
201 *
202 * @current_bd_ptr current buffer descriptor processed
203 * @base_bd_ptr first element of buffer descriptor array
204 * @unused padding. The SDMA engine expects an array of 128 byte
205 * control blocks
206 */
207 struct sdma_channel_control {
208 u32 current_bd_ptr;
209 u32 base_bd_ptr;
210 u32 unused[2];
211 } __attribute__ ((packed));
212
213 /**
214 * struct sdma_state_registers - SDMA context for a channel
215 *
216 * @pc: program counter
217 * @t: test bit: status of arithmetic & test instruction
218 * @rpc: return program counter
219 * @sf: source fault while loading data
220 * @spc: loop start program counter
221 * @df: destination fault while storing data
222 * @epc: loop end program counter
223 * @lm: loop mode
224 */
225 struct sdma_state_registers {
226 u32 pc :14;
227 u32 unused1: 1;
228 u32 t : 1;
229 u32 rpc :14;
230 u32 unused0: 1;
231 u32 sf : 1;
232 u32 spc :14;
233 u32 unused2: 1;
234 u32 df : 1;
235 u32 epc :14;
236 u32 lm : 2;
237 } __attribute__ ((packed));
238
239 /**
240 * struct sdma_context_data - sdma context specific to a channel
241 *
242 * @channel_state: channel state bits
243 * @gReg: general registers
244 * @mda: burst dma destination address register
245 * @msa: burst dma source address register
246 * @ms: burst dma status register
247 * @md: burst dma data register
248 * @pda: peripheral dma destination address register
249 * @psa: peripheral dma source address register
250 * @ps: peripheral dma status register
251 * @pd: peripheral dma data register
252 * @ca: CRC polynomial register
253 * @cs: CRC accumulator register
254 * @dda: dedicated core destination address register
255 * @dsa: dedicated core source address register
256 * @ds: dedicated core status register
257 * @dd: dedicated core data register
258 */
259 struct sdma_context_data {
260 struct sdma_state_registers channel_state;
261 u32 gReg[8];
262 u32 mda;
263 u32 msa;
264 u32 ms;
265 u32 md;
266 u32 pda;
267 u32 psa;
268 u32 ps;
269 u32 pd;
270 u32 ca;
271 u32 cs;
272 u32 dda;
273 u32 dsa;
274 u32 ds;
275 u32 dd;
276 u32 scratch0;
277 u32 scratch1;
278 u32 scratch2;
279 u32 scratch3;
280 u32 scratch4;
281 u32 scratch5;
282 u32 scratch6;
283 u32 scratch7;
284 } __attribute__ ((packed));
285
286 #define NUM_BD (int)(PAGE_SIZE / sizeof(struct sdma_buffer_descriptor))
287
288 struct sdma_engine;
289
290 /**
291 * struct sdma_channel - housekeeping for a SDMA channel
292 *
293 * @sdma pointer to the SDMA engine for this channel
294 * @channel the channel number, matches dmaengine chan_id + 1
295 * @direction transfer type. Needed for setting SDMA script
296 * @peripheral_type Peripheral type. Needed for setting SDMA script
297 * @event_id0 aka dma request line
298 * @event_id1 for channels that use 2 events
299 * @word_size peripheral access size
300 * @buf_tail ID of the buffer that was processed
301 * @num_bd max NUM_BD. number of descriptors currently handling
302 */
303 struct sdma_channel {
304 struct sdma_engine *sdma;
305 unsigned int channel;
306 enum dma_transfer_direction direction;
307 enum sdma_peripheral_type peripheral_type;
308 unsigned int event_id0;
309 unsigned int event_id1;
310 enum dma_slave_buswidth word_size;
311 unsigned int buf_tail;
312 unsigned int num_bd;
313 unsigned int period_len;
314 struct sdma_buffer_descriptor *bd;
315 dma_addr_t bd_phys;
316 unsigned int pc_from_device, pc_to_device;
317 unsigned int device_to_device;
318 unsigned long flags;
319 dma_addr_t per_address, per_address2;
320 unsigned long event_mask[2];
321 unsigned long watermark_level;
322 u32 shp_addr, per_addr;
323 struct dma_chan chan;
324 spinlock_t lock;
325 struct dma_async_tx_descriptor desc;
326 enum dma_status status;
327 unsigned int chn_count;
328 unsigned int chn_real_count;
329 struct tasklet_struct tasklet;
330 struct imx_dma_data data;
331 };
332
333 #define IMX_DMA_SG_LOOP BIT(0)
334
335 #define MAX_DMA_CHANNELS 32
336 #define MXC_SDMA_DEFAULT_PRIORITY 1
337 #define MXC_SDMA_MIN_PRIORITY 1
338 #define MXC_SDMA_MAX_PRIORITY 7
339
340 #define SDMA_FIRMWARE_MAGIC 0x414d4453
341
342 /**
343 * struct sdma_firmware_header - Layout of the firmware image
344 *
345 * @magic "SDMA"
346 * @version_major increased whenever layout of struct sdma_script_start_addrs
347 * changes.
348 * @version_minor firmware minor version (for binary compatible changes)
349 * @script_addrs_start offset of struct sdma_script_start_addrs in this image
350 * @num_script_addrs Number of script addresses in this image
351 * @ram_code_start offset of SDMA ram image in this firmware image
352 * @ram_code_size size of SDMA ram image
353 * @script_addrs Stores the start address of the SDMA scripts
354 * (in SDMA memory space)
355 */
356 struct sdma_firmware_header {
357 u32 magic;
358 u32 version_major;
359 u32 version_minor;
360 u32 script_addrs_start;
361 u32 num_script_addrs;
362 u32 ram_code_start;
363 u32 ram_code_size;
364 };
365
366 struct sdma_driver_data {
367 int chnenbl0;
368 int num_events;
369 struct sdma_script_start_addrs *script_addrs;
370 };
371
372 struct sdma_engine {
373 struct device *dev;
374 struct device_dma_parameters dma_parms;
375 struct sdma_channel channel[MAX_DMA_CHANNELS];
376 struct sdma_channel_control *channel_control;
377 void __iomem *regs;
378 struct sdma_context_data *context;
379 dma_addr_t context_phys;
380 struct dma_device dma_device;
381 struct clk *clk_ipg;
382 struct clk *clk_ahb;
383 spinlock_t channel_0_lock;
384 u32 script_number;
385 struct sdma_script_start_addrs *script_addrs;
386 const struct sdma_driver_data *drvdata;
387 u32 spba_start_addr;
388 u32 spba_end_addr;
389 unsigned int irq;
390 };
391
392 static struct sdma_driver_data sdma_imx31 = {
393 .chnenbl0 = SDMA_CHNENBL0_IMX31,
394 .num_events = 32,
395 };
396
397 static struct sdma_script_start_addrs sdma_script_imx25 = {
398 .ap_2_ap_addr = 729,
399 .uart_2_mcu_addr = 904,
400 .per_2_app_addr = 1255,
401 .mcu_2_app_addr = 834,
402 .uartsh_2_mcu_addr = 1120,
403 .per_2_shp_addr = 1329,
404 .mcu_2_shp_addr = 1048,
405 .ata_2_mcu_addr = 1560,
406 .mcu_2_ata_addr = 1479,
407 .app_2_per_addr = 1189,
408 .app_2_mcu_addr = 770,
409 .shp_2_per_addr = 1407,
410 .shp_2_mcu_addr = 979,
411 };
412
413 static struct sdma_driver_data sdma_imx25 = {
414 .chnenbl0 = SDMA_CHNENBL0_IMX35,
415 .num_events = 48,
416 .script_addrs = &sdma_script_imx25,
417 };
418
419 static struct sdma_driver_data sdma_imx35 = {
420 .chnenbl0 = SDMA_CHNENBL0_IMX35,
421 .num_events = 48,
422 };
423
424 static struct sdma_script_start_addrs sdma_script_imx51 = {
425 .ap_2_ap_addr = 642,
426 .uart_2_mcu_addr = 817,
427 .mcu_2_app_addr = 747,
428 .mcu_2_shp_addr = 961,
429 .ata_2_mcu_addr = 1473,
430 .mcu_2_ata_addr = 1392,
431 .app_2_per_addr = 1033,
432 .app_2_mcu_addr = 683,
433 .shp_2_per_addr = 1251,
434 .shp_2_mcu_addr = 892,
435 };
436
437 static struct sdma_driver_data sdma_imx51 = {
438 .chnenbl0 = SDMA_CHNENBL0_IMX35,
439 .num_events = 48,
440 .script_addrs = &sdma_script_imx51,
441 };
442
443 static struct sdma_script_start_addrs sdma_script_imx53 = {
444 .ap_2_ap_addr = 642,
445 .app_2_mcu_addr = 683,
446 .mcu_2_app_addr = 747,
447 .uart_2_mcu_addr = 817,
448 .shp_2_mcu_addr = 891,
449 .mcu_2_shp_addr = 960,
450 .uartsh_2_mcu_addr = 1032,
451 .spdif_2_mcu_addr = 1100,
452 .mcu_2_spdif_addr = 1134,
453 .firi_2_mcu_addr = 1193,
454 .mcu_2_firi_addr = 1290,
455 };
456
457 static struct sdma_driver_data sdma_imx53 = {
458 .chnenbl0 = SDMA_CHNENBL0_IMX35,
459 .num_events = 48,
460 .script_addrs = &sdma_script_imx53,
461 };
462
463 static struct sdma_script_start_addrs sdma_script_imx6q = {
464 .ap_2_ap_addr = 642,
465 .uart_2_mcu_addr = 817,
466 .mcu_2_app_addr = 747,
467 .per_2_per_addr = 6331,
468 .uartsh_2_mcu_addr = 1032,
469 .mcu_2_shp_addr = 960,
470 .app_2_mcu_addr = 683,
471 .shp_2_mcu_addr = 891,
472 .spdif_2_mcu_addr = 1100,
473 .mcu_2_spdif_addr = 1134,
474 };
475
476 static struct sdma_driver_data sdma_imx6q = {
477 .chnenbl0 = SDMA_CHNENBL0_IMX35,
478 .num_events = 48,
479 .script_addrs = &sdma_script_imx6q,
480 };
481
482 static struct sdma_script_start_addrs sdma_script_imx7d = {
483 .ap_2_ap_addr = 644,
484 .uart_2_mcu_addr = 819,
485 .mcu_2_app_addr = 749,
486 .uartsh_2_mcu_addr = 1034,
487 .mcu_2_shp_addr = 962,
488 .app_2_mcu_addr = 685,
489 .shp_2_mcu_addr = 893,
490 .spdif_2_mcu_addr = 1102,
491 .mcu_2_spdif_addr = 1136,
492 };
493
494 static struct sdma_driver_data sdma_imx7d = {
495 .chnenbl0 = SDMA_CHNENBL0_IMX35,
496 .num_events = 48,
497 .script_addrs = &sdma_script_imx7d,
498 };
499
500 static const struct platform_device_id sdma_devtypes[] = {
501 {
502 .name = "imx25-sdma",
503 .driver_data = (unsigned long)&sdma_imx25,
504 }, {
505 .name = "imx31-sdma",
506 .driver_data = (unsigned long)&sdma_imx31,
507 }, {
508 .name = "imx35-sdma",
509 .driver_data = (unsigned long)&sdma_imx35,
510 }, {
511 .name = "imx51-sdma",
512 .driver_data = (unsigned long)&sdma_imx51,
513 }, {
514 .name = "imx53-sdma",
515 .driver_data = (unsigned long)&sdma_imx53,
516 }, {
517 .name = "imx6q-sdma",
518 .driver_data = (unsigned long)&sdma_imx6q,
519 }, {
520 .name = "imx7d-sdma",
521 .driver_data = (unsigned long)&sdma_imx7d,
522 }, {
523 /* sentinel */
524 }
525 };
526 MODULE_DEVICE_TABLE(platform, sdma_devtypes);
527
528 static const struct of_device_id sdma_dt_ids[] = {
529 { .compatible = "fsl,imx6q-sdma", .data = &sdma_imx6q, },
530 { .compatible = "fsl,imx53-sdma", .data = &sdma_imx53, },
531 { .compatible = "fsl,imx51-sdma", .data = &sdma_imx51, },
532 { .compatible = "fsl,imx35-sdma", .data = &sdma_imx35, },
533 { .compatible = "fsl,imx31-sdma", .data = &sdma_imx31, },
534 { .compatible = "fsl,imx25-sdma", .data = &sdma_imx25, },
535 { .compatible = "fsl,imx7d-sdma", .data = &sdma_imx7d, },
536 { /* sentinel */ }
537 };
538 MODULE_DEVICE_TABLE(of, sdma_dt_ids);
539
540 #define SDMA_H_CONFIG_DSPDMA BIT(12) /* indicates if the DSPDMA is used */
541 #define SDMA_H_CONFIG_RTD_PINS BIT(11) /* indicates if Real-Time Debug pins are enabled */
542 #define SDMA_H_CONFIG_ACR BIT(4) /* indicates if AHB freq /core freq = 2 or 1 */
543 #define SDMA_H_CONFIG_CSM (3) /* indicates which context switch mode is selected*/
544
545 static inline u32 chnenbl_ofs(struct sdma_engine *sdma, unsigned int event)
546 {
547 u32 chnenbl0 = sdma->drvdata->chnenbl0;
548 return chnenbl0 + event * 4;
549 }
550
551 static int sdma_config_ownership(struct sdma_channel *sdmac,
552 bool event_override, bool mcu_override, bool dsp_override)
553 {
554 struct sdma_engine *sdma = sdmac->sdma;
555 int channel = sdmac->channel;
556 unsigned long evt, mcu, dsp;
557
558 if (event_override && mcu_override && dsp_override)
559 return -EINVAL;
560
561 evt = readl_relaxed(sdma->regs + SDMA_H_EVTOVR);
562 mcu = readl_relaxed(sdma->regs + SDMA_H_HOSTOVR);
563 dsp = readl_relaxed(sdma->regs + SDMA_H_DSPOVR);
564
565 if (dsp_override)
566 __clear_bit(channel, &dsp);
567 else
568 __set_bit(channel, &dsp);
569
570 if (event_override)
571 __clear_bit(channel, &evt);
572 else
573 __set_bit(channel, &evt);
574
575 if (mcu_override)
576 __clear_bit(channel, &mcu);
577 else
578 __set_bit(channel, &mcu);
579
580 writel_relaxed(evt, sdma->regs + SDMA_H_EVTOVR);
581 writel_relaxed(mcu, sdma->regs + SDMA_H_HOSTOVR);
582 writel_relaxed(dsp, sdma->regs + SDMA_H_DSPOVR);
583
584 return 0;
585 }
586
587 static void sdma_enable_channel(struct sdma_engine *sdma, int channel)
588 {
589 writel(BIT(channel), sdma->regs + SDMA_H_START);
590 }
591
592 /*
593 * sdma_run_channel0 - run a channel and wait till it's done
594 */
595 static int sdma_run_channel0(struct sdma_engine *sdma)
596 {
597 int ret;
598 u32 reg;
599
600 sdma_enable_channel(sdma, 0);
601
602 ret = readl_relaxed_poll_timeout_atomic(sdma->regs + SDMA_H_STATSTOP,
603 reg, !(reg & 1), 1, 500);
604 if (ret)
605 dev_err(sdma->dev, "Timeout waiting for CH0 ready\n");
606
607 /* Set bits of CONFIG register with dynamic context switching */
608 if (readl(sdma->regs + SDMA_H_CONFIG) == 0)
609 writel_relaxed(SDMA_H_CONFIG_CSM, sdma->regs + SDMA_H_CONFIG);
610
611 return ret;
612 }
613
614 static int sdma_load_script(struct sdma_engine *sdma, void *buf, int size,
615 u32 address)
616 {
617 struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
618 void *buf_virt;
619 dma_addr_t buf_phys;
620 int ret;
621 unsigned long flags;
622
623 buf_virt = dma_alloc_coherent(NULL,
624 size,
625 &buf_phys, GFP_KERNEL);
626 if (!buf_virt) {
627 return -ENOMEM;
628 }
629
630 spin_lock_irqsave(&sdma->channel_0_lock, flags);
631
632 bd0->mode.command = C0_SETPM;
633 bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD;
634 bd0->mode.count = size / 2;
635 bd0->buffer_addr = buf_phys;
636 bd0->ext_buffer_addr = address;
637
638 memcpy(buf_virt, buf, size);
639
640 ret = sdma_run_channel0(sdma);
641
642 spin_unlock_irqrestore(&sdma->channel_0_lock, flags);
643
644 dma_free_coherent(NULL, size, buf_virt, buf_phys);
645
646 return ret;
647 }
648
649 static void sdma_event_enable(struct sdma_channel *sdmac, unsigned int event)
650 {
651 struct sdma_engine *sdma = sdmac->sdma;
652 int channel = sdmac->channel;
653 unsigned long val;
654 u32 chnenbl = chnenbl_ofs(sdma, event);
655
656 val = readl_relaxed(sdma->regs + chnenbl);
657 __set_bit(channel, &val);
658 writel_relaxed(val, sdma->regs + chnenbl);
659 }
660
661 static void sdma_event_disable(struct sdma_channel *sdmac, unsigned int event)
662 {
663 struct sdma_engine *sdma = sdmac->sdma;
664 int channel = sdmac->channel;
665 u32 chnenbl = chnenbl_ofs(sdma, event);
666 unsigned long val;
667
668 val = readl_relaxed(sdma->regs + chnenbl);
669 __clear_bit(channel, &val);
670 writel_relaxed(val, sdma->regs + chnenbl);
671 }
672
673 static void sdma_update_channel_loop(struct sdma_channel *sdmac)
674 {
675 struct sdma_buffer_descriptor *bd;
676 int error = 0;
677 enum dma_status old_status = sdmac->status;
678
679 /*
680 * loop mode. Iterate over descriptors, re-setup them and
681 * call callback function.
682 */
683 while (1) {
684 bd = &sdmac->bd[sdmac->buf_tail];
685
686 if (bd->mode.status & BD_DONE)
687 break;
688
689 if (bd->mode.status & BD_RROR) {
690 bd->mode.status &= ~BD_RROR;
691 sdmac->status = DMA_ERROR;
692 error = -EIO;
693 }
694
695 /*
696 * We use bd->mode.count to calculate the residue, since contains
697 * the number of bytes present in the current buffer descriptor.
698 */
699
700 sdmac->chn_real_count = bd->mode.count;
701 bd->mode.status |= BD_DONE;
702 bd->mode.count = sdmac->period_len;
703
704 /*
705 * The callback is called from the interrupt context in order
706 * to reduce latency and to avoid the risk of altering the
707 * SDMA transaction status by the time the client tasklet is
708 * executed.
709 */
710
711 dmaengine_desc_get_callback_invoke(&sdmac->desc, NULL);
712
713 sdmac->buf_tail++;
714 sdmac->buf_tail %= sdmac->num_bd;
715
716 if (error)
717 sdmac->status = old_status;
718 }
719 }
720
721 static void mxc_sdma_handle_channel_normal(unsigned long data)
722 {
723 struct sdma_channel *sdmac = (struct sdma_channel *) data;
724 struct sdma_buffer_descriptor *bd;
725 int i, error = 0;
726
727 sdmac->chn_real_count = 0;
728 /*
729 * non loop mode. Iterate over all descriptors, collect
730 * errors and call callback function
731 */
732 for (i = 0; i < sdmac->num_bd; i++) {
733 bd = &sdmac->bd[i];
734
735 if (bd->mode.status & (BD_DONE | BD_RROR))
736 error = -EIO;
737 sdmac->chn_real_count += bd->mode.count;
738 }
739
740 if (error)
741 sdmac->status = DMA_ERROR;
742 else
743 sdmac->status = DMA_COMPLETE;
744
745 dma_cookie_complete(&sdmac->desc);
746
747 dmaengine_desc_get_callback_invoke(&sdmac->desc, NULL);
748 }
749
750 static irqreturn_t sdma_int_handler(int irq, void *dev_id)
751 {
752 struct sdma_engine *sdma = dev_id;
753 unsigned long stat;
754
755 stat = readl_relaxed(sdma->regs + SDMA_H_INTR);
756 writel_relaxed(stat, sdma->regs + SDMA_H_INTR);
757 /* channel 0 is special and not handled here, see run_channel0() */
758 stat &= ~1;
759
760 while (stat) {
761 int channel = fls(stat) - 1;
762 struct sdma_channel *sdmac = &sdma->channel[channel];
763
764 if (sdmac->flags & IMX_DMA_SG_LOOP)
765 sdma_update_channel_loop(sdmac);
766 else
767 tasklet_schedule(&sdmac->tasklet);
768
769 __clear_bit(channel, &stat);
770 }
771
772 return IRQ_HANDLED;
773 }
774
775 /*
776 * sets the pc of SDMA script according to the peripheral type
777 */
778 static void sdma_get_pc(struct sdma_channel *sdmac,
779 enum sdma_peripheral_type peripheral_type)
780 {
781 struct sdma_engine *sdma = sdmac->sdma;
782 int per_2_emi = 0, emi_2_per = 0;
783 /*
784 * These are needed once we start to support transfers between
785 * two peripherals or memory-to-memory transfers
786 */
787 int per_2_per = 0;
788
789 sdmac->pc_from_device = 0;
790 sdmac->pc_to_device = 0;
791 sdmac->device_to_device = 0;
792
793 switch (peripheral_type) {
794 case IMX_DMATYPE_MEMORY:
795 break;
796 case IMX_DMATYPE_DSP:
797 emi_2_per = sdma->script_addrs->bp_2_ap_addr;
798 per_2_emi = sdma->script_addrs->ap_2_bp_addr;
799 break;
800 case IMX_DMATYPE_FIRI:
801 per_2_emi = sdma->script_addrs->firi_2_mcu_addr;
802 emi_2_per = sdma->script_addrs->mcu_2_firi_addr;
803 break;
804 case IMX_DMATYPE_UART:
805 per_2_emi = sdma->script_addrs->uart_2_mcu_addr;
806 emi_2_per = sdma->script_addrs->mcu_2_app_addr;
807 break;
808 case IMX_DMATYPE_UART_SP:
809 per_2_emi = sdma->script_addrs->uartsh_2_mcu_addr;
810 emi_2_per = sdma->script_addrs->mcu_2_shp_addr;
811 break;
812 case IMX_DMATYPE_ATA:
813 per_2_emi = sdma->script_addrs->ata_2_mcu_addr;
814 emi_2_per = sdma->script_addrs->mcu_2_ata_addr;
815 break;
816 case IMX_DMATYPE_CSPI:
817 case IMX_DMATYPE_EXT:
818 case IMX_DMATYPE_SSI:
819 case IMX_DMATYPE_SAI:
820 per_2_emi = sdma->script_addrs->app_2_mcu_addr;
821 emi_2_per = sdma->script_addrs->mcu_2_app_addr;
822 break;
823 case IMX_DMATYPE_SSI_DUAL:
824 per_2_emi = sdma->script_addrs->ssish_2_mcu_addr;
825 emi_2_per = sdma->script_addrs->mcu_2_ssish_addr;
826 break;
827 case IMX_DMATYPE_SSI_SP:
828 case IMX_DMATYPE_MMC:
829 case IMX_DMATYPE_SDHC:
830 case IMX_DMATYPE_CSPI_SP:
831 case IMX_DMATYPE_ESAI:
832 case IMX_DMATYPE_MSHC_SP:
833 per_2_emi = sdma->script_addrs->shp_2_mcu_addr;
834 emi_2_per = sdma->script_addrs->mcu_2_shp_addr;
835 break;
836 case IMX_DMATYPE_ASRC:
837 per_2_emi = sdma->script_addrs->asrc_2_mcu_addr;
838 emi_2_per = sdma->script_addrs->asrc_2_mcu_addr;
839 per_2_per = sdma->script_addrs->per_2_per_addr;
840 break;
841 case IMX_DMATYPE_ASRC_SP:
842 per_2_emi = sdma->script_addrs->shp_2_mcu_addr;
843 emi_2_per = sdma->script_addrs->mcu_2_shp_addr;
844 per_2_per = sdma->script_addrs->per_2_per_addr;
845 break;
846 case IMX_DMATYPE_MSHC:
847 per_2_emi = sdma->script_addrs->mshc_2_mcu_addr;
848 emi_2_per = sdma->script_addrs->mcu_2_mshc_addr;
849 break;
850 case IMX_DMATYPE_CCM:
851 per_2_emi = sdma->script_addrs->dptc_dvfs_addr;
852 break;
853 case IMX_DMATYPE_SPDIF:
854 per_2_emi = sdma->script_addrs->spdif_2_mcu_addr;
855 emi_2_per = sdma->script_addrs->mcu_2_spdif_addr;
856 break;
857 case IMX_DMATYPE_IPU_MEMORY:
858 emi_2_per = sdma->script_addrs->ext_mem_2_ipu_addr;
859 break;
860 default:
861 break;
862 }
863
864 sdmac->pc_from_device = per_2_emi;
865 sdmac->pc_to_device = emi_2_per;
866 sdmac->device_to_device = per_2_per;
867 }
868
869 static int sdma_load_context(struct sdma_channel *sdmac)
870 {
871 struct sdma_engine *sdma = sdmac->sdma;
872 int channel = sdmac->channel;
873 int load_address;
874 struct sdma_context_data *context = sdma->context;
875 struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
876 int ret;
877 unsigned long flags;
878
879 if (sdmac->direction == DMA_DEV_TO_MEM)
880 load_address = sdmac->pc_from_device;
881 else if (sdmac->direction == DMA_DEV_TO_DEV)
882 load_address = sdmac->device_to_device;
883 else
884 load_address = sdmac->pc_to_device;
885
886 if (load_address < 0)
887 return load_address;
888
889 dev_dbg(sdma->dev, "load_address = %d\n", load_address);
890 dev_dbg(sdma->dev, "wml = 0x%08x\n", (u32)sdmac->watermark_level);
891 dev_dbg(sdma->dev, "shp_addr = 0x%08x\n", sdmac->shp_addr);
892 dev_dbg(sdma->dev, "per_addr = 0x%08x\n", sdmac->per_addr);
893 dev_dbg(sdma->dev, "event_mask0 = 0x%08x\n", (u32)sdmac->event_mask[0]);
894 dev_dbg(sdma->dev, "event_mask1 = 0x%08x\n", (u32)sdmac->event_mask[1]);
895
896 spin_lock_irqsave(&sdma->channel_0_lock, flags);
897
898 memset(context, 0, sizeof(*context));
899 context->channel_state.pc = load_address;
900
901 /* Send by context the event mask,base address for peripheral
902 * and watermark level
903 */
904 context->gReg[0] = sdmac->event_mask[1];
905 context->gReg[1] = sdmac->event_mask[0];
906 context->gReg[2] = sdmac->per_addr;
907 context->gReg[6] = sdmac->shp_addr;
908 context->gReg[7] = sdmac->watermark_level;
909
910 bd0->mode.command = C0_SETDM;
911 bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD;
912 bd0->mode.count = sizeof(*context) / 4;
913 bd0->buffer_addr = sdma->context_phys;
914 bd0->ext_buffer_addr = 2048 + (sizeof(*context) / 4) * channel;
915 ret = sdma_run_channel0(sdma);
916
917 spin_unlock_irqrestore(&sdma->channel_0_lock, flags);
918
919 return ret;
920 }
921
922 static struct sdma_channel *to_sdma_chan(struct dma_chan *chan)
923 {
924 return container_of(chan, struct sdma_channel, chan);
925 }
926
927 static int sdma_disable_channel(struct dma_chan *chan)
928 {
929 struct sdma_channel *sdmac = to_sdma_chan(chan);
930 struct sdma_engine *sdma = sdmac->sdma;
931 int channel = sdmac->channel;
932
933 writel_relaxed(BIT(channel), sdma->regs + SDMA_H_STATSTOP);
934 sdmac->status = DMA_ERROR;
935
936 return 0;
937 }
938
939 static void sdma_set_watermarklevel_for_p2p(struct sdma_channel *sdmac)
940 {
941 struct sdma_engine *sdma = sdmac->sdma;
942
943 int lwml = sdmac->watermark_level & SDMA_WATERMARK_LEVEL_LWML;
944 int hwml = (sdmac->watermark_level & SDMA_WATERMARK_LEVEL_HWML) >> 16;
945
946 set_bit(sdmac->event_id0 % 32, &sdmac->event_mask[1]);
947 set_bit(sdmac->event_id1 % 32, &sdmac->event_mask[0]);
948
949 if (sdmac->event_id0 > 31)
950 sdmac->watermark_level |= SDMA_WATERMARK_LEVEL_LWE;
951
952 if (sdmac->event_id1 > 31)
953 sdmac->watermark_level |= SDMA_WATERMARK_LEVEL_HWE;
954
955 /*
956 * If LWML(src_maxburst) > HWML(dst_maxburst), we need
957 * swap LWML and HWML of INFO(A.3.2.5.1), also need swap
958 * r0(event_mask[1]) and r1(event_mask[0]).
959 */
960 if (lwml > hwml) {
961 sdmac->watermark_level &= ~(SDMA_WATERMARK_LEVEL_LWML |
962 SDMA_WATERMARK_LEVEL_HWML);
963 sdmac->watermark_level |= hwml;
964 sdmac->watermark_level |= lwml << 16;
965 swap(sdmac->event_mask[0], sdmac->event_mask[1]);
966 }
967
968 if (sdmac->per_address2 >= sdma->spba_start_addr &&
969 sdmac->per_address2 <= sdma->spba_end_addr)
970 sdmac->watermark_level |= SDMA_WATERMARK_LEVEL_SP;
971
972 if (sdmac->per_address >= sdma->spba_start_addr &&
973 sdmac->per_address <= sdma->spba_end_addr)
974 sdmac->watermark_level |= SDMA_WATERMARK_LEVEL_DP;
975
976 sdmac->watermark_level |= SDMA_WATERMARK_LEVEL_CONT;
977 }
978
979 static int sdma_config_channel(struct dma_chan *chan)
980 {
981 struct sdma_channel *sdmac = to_sdma_chan(chan);
982 int ret;
983
984 sdma_disable_channel(chan);
985
986 sdmac->event_mask[0] = 0;
987 sdmac->event_mask[1] = 0;
988 sdmac->shp_addr = 0;
989 sdmac->per_addr = 0;
990
991 if (sdmac->event_id0) {
992 if (sdmac->event_id0 >= sdmac->sdma->drvdata->num_events)
993 return -EINVAL;
994 sdma_event_enable(sdmac, sdmac->event_id0);
995 }
996
997 if (sdmac->event_id1) {
998 if (sdmac->event_id1 >= sdmac->sdma->drvdata->num_events)
999 return -EINVAL;
1000 sdma_event_enable(sdmac, sdmac->event_id1);
1001 }
1002
1003 switch (sdmac->peripheral_type) {
1004 case IMX_DMATYPE_DSP:
1005 sdma_config_ownership(sdmac, false, true, true);
1006 break;
1007 case IMX_DMATYPE_MEMORY:
1008 sdma_config_ownership(sdmac, false, true, false);
1009 break;
1010 default:
1011 sdma_config_ownership(sdmac, true, true, false);
1012 break;
1013 }
1014
1015 sdma_get_pc(sdmac, sdmac->peripheral_type);
1016
1017 if ((sdmac->peripheral_type != IMX_DMATYPE_MEMORY) &&
1018 (sdmac->peripheral_type != IMX_DMATYPE_DSP)) {
1019 /* Handle multiple event channels differently */
1020 if (sdmac->event_id1) {
1021 if (sdmac->peripheral_type == IMX_DMATYPE_ASRC_SP ||
1022 sdmac->peripheral_type == IMX_DMATYPE_ASRC)
1023 sdma_set_watermarklevel_for_p2p(sdmac);
1024 } else
1025 __set_bit(sdmac->event_id0, sdmac->event_mask);
1026
1027 /* Address */
1028 sdmac->shp_addr = sdmac->per_address;
1029 sdmac->per_addr = sdmac->per_address2;
1030 } else {
1031 sdmac->watermark_level = 0; /* FIXME: M3_BASE_ADDRESS */
1032 }
1033
1034 ret = sdma_load_context(sdmac);
1035
1036 return ret;
1037 }
1038
1039 static int sdma_set_channel_priority(struct sdma_channel *sdmac,
1040 unsigned int priority)
1041 {
1042 struct sdma_engine *sdma = sdmac->sdma;
1043 int channel = sdmac->channel;
1044
1045 if (priority < MXC_SDMA_MIN_PRIORITY
1046 || priority > MXC_SDMA_MAX_PRIORITY) {
1047 return -EINVAL;
1048 }
1049
1050 writel_relaxed(priority, sdma->regs + SDMA_CHNPRI_0 + 4 * channel);
1051
1052 return 0;
1053 }
1054
1055 static int sdma_request_channel(struct sdma_channel *sdmac)
1056 {
1057 struct sdma_engine *sdma = sdmac->sdma;
1058 int channel = sdmac->channel;
1059 int ret = -EBUSY;
1060
1061 sdmac->bd = dma_zalloc_coherent(NULL, PAGE_SIZE, &sdmac->bd_phys,
1062 GFP_KERNEL);
1063 if (!sdmac->bd) {
1064 ret = -ENOMEM;
1065 goto out;
1066 }
1067
1068 sdma->channel_control[channel].base_bd_ptr = sdmac->bd_phys;
1069 sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
1070
1071 sdma_set_channel_priority(sdmac, MXC_SDMA_DEFAULT_PRIORITY);
1072 return 0;
1073 out:
1074
1075 return ret;
1076 }
1077
1078 static dma_cookie_t sdma_tx_submit(struct dma_async_tx_descriptor *tx)
1079 {
1080 unsigned long flags;
1081 struct sdma_channel *sdmac = to_sdma_chan(tx->chan);
1082 dma_cookie_t cookie;
1083
1084 spin_lock_irqsave(&sdmac->lock, flags);
1085
1086 cookie = dma_cookie_assign(tx);
1087
1088 spin_unlock_irqrestore(&sdmac->lock, flags);
1089
1090 return cookie;
1091 }
1092
1093 static int sdma_alloc_chan_resources(struct dma_chan *chan)
1094 {
1095 struct sdma_channel *sdmac = to_sdma_chan(chan);
1096 struct imx_dma_data *data = chan->private;
1097 int prio, ret;
1098
1099 if (!data)
1100 return -EINVAL;
1101
1102 switch (data->priority) {
1103 case DMA_PRIO_HIGH:
1104 prio = 3;
1105 break;
1106 case DMA_PRIO_MEDIUM:
1107 prio = 2;
1108 break;
1109 case DMA_PRIO_LOW:
1110 default:
1111 prio = 1;
1112 break;
1113 }
1114
1115 sdmac->peripheral_type = data->peripheral_type;
1116 sdmac->event_id0 = data->dma_request;
1117 sdmac->event_id1 = data->dma_request2;
1118
1119 ret = clk_enable(sdmac->sdma->clk_ipg);
1120 if (ret)
1121 return ret;
1122 ret = clk_enable(sdmac->sdma->clk_ahb);
1123 if (ret)
1124 goto disable_clk_ipg;
1125
1126 ret = sdma_request_channel(sdmac);
1127 if (ret)
1128 goto disable_clk_ahb;
1129
1130 ret = sdma_set_channel_priority(sdmac, prio);
1131 if (ret)
1132 goto disable_clk_ahb;
1133
1134 dma_async_tx_descriptor_init(&sdmac->desc, chan);
1135 sdmac->desc.tx_submit = sdma_tx_submit;
1136 /* txd.flags will be overwritten in prep funcs */
1137 sdmac->desc.flags = DMA_CTRL_ACK;
1138
1139 return 0;
1140
1141 disable_clk_ahb:
1142 clk_disable(sdmac->sdma->clk_ahb);
1143 disable_clk_ipg:
1144 clk_disable(sdmac->sdma->clk_ipg);
1145 return ret;
1146 }
1147
1148 static void sdma_free_chan_resources(struct dma_chan *chan)
1149 {
1150 struct sdma_channel *sdmac = to_sdma_chan(chan);
1151 struct sdma_engine *sdma = sdmac->sdma;
1152
1153 sdma_disable_channel(chan);
1154
1155 if (sdmac->event_id0)
1156 sdma_event_disable(sdmac, sdmac->event_id0);
1157 if (sdmac->event_id1)
1158 sdma_event_disable(sdmac, sdmac->event_id1);
1159
1160 sdmac->event_id0 = 0;
1161 sdmac->event_id1 = 0;
1162
1163 sdma_set_channel_priority(sdmac, 0);
1164
1165 dma_free_coherent(NULL, PAGE_SIZE, sdmac->bd, sdmac->bd_phys);
1166
1167 clk_disable(sdma->clk_ipg);
1168 clk_disable(sdma->clk_ahb);
1169 }
1170
1171 static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
1172 struct dma_chan *chan, struct scatterlist *sgl,
1173 unsigned int sg_len, enum dma_transfer_direction direction,
1174 unsigned long flags, void *context)
1175 {
1176 struct sdma_channel *sdmac = to_sdma_chan(chan);
1177 struct sdma_engine *sdma = sdmac->sdma;
1178 int ret, i, count;
1179 int channel = sdmac->channel;
1180 struct scatterlist *sg;
1181
1182 if (sdmac->status == DMA_IN_PROGRESS)
1183 return NULL;
1184 sdmac->status = DMA_IN_PROGRESS;
1185
1186 sdmac->flags = 0;
1187
1188 sdmac->buf_tail = 0;
1189
1190 dev_dbg(sdma->dev, "setting up %d entries for channel %d.\n",
1191 sg_len, channel);
1192
1193 sdmac->direction = direction;
1194 ret = sdma_load_context(sdmac);
1195 if (ret)
1196 goto err_out;
1197
1198 if (sg_len > NUM_BD) {
1199 dev_err(sdma->dev, "SDMA channel %d: maximum number of sg exceeded: %d > %d\n",
1200 channel, sg_len, NUM_BD);
1201 ret = -EINVAL;
1202 goto err_out;
1203 }
1204
1205 sdmac->chn_count = 0;
1206 for_each_sg(sgl, sg, sg_len, i) {
1207 struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
1208 int param;
1209
1210 bd->buffer_addr = sg->dma_address;
1211
1212 count = sg_dma_len(sg);
1213
1214 if (count > 0xffff) {
1215 dev_err(sdma->dev, "SDMA channel %d: maximum bytes for sg entry exceeded: %d > %d\n",
1216 channel, count, 0xffff);
1217 ret = -EINVAL;
1218 goto err_out;
1219 }
1220
1221 bd->mode.count = count;
1222 sdmac->chn_count += count;
1223
1224 if (sdmac->word_size > DMA_SLAVE_BUSWIDTH_4_BYTES) {
1225 ret = -EINVAL;
1226 goto err_out;
1227 }
1228
1229 switch (sdmac->word_size) {
1230 case DMA_SLAVE_BUSWIDTH_4_BYTES:
1231 bd->mode.command = 0;
1232 if (count & 3 || sg->dma_address & 3)
1233 return NULL;
1234 break;
1235 case DMA_SLAVE_BUSWIDTH_2_BYTES:
1236 bd->mode.command = 2;
1237 if (count & 1 || sg->dma_address & 1)
1238 return NULL;
1239 break;
1240 case DMA_SLAVE_BUSWIDTH_1_BYTE:
1241 bd->mode.command = 1;
1242 break;
1243 default:
1244 return NULL;
1245 }
1246
1247 param = BD_DONE | BD_EXTD | BD_CONT;
1248
1249 if (i + 1 == sg_len) {
1250 param |= BD_INTR;
1251 param |= BD_LAST;
1252 param &= ~BD_CONT;
1253 }
1254
1255 dev_dbg(sdma->dev, "entry %d: count: %d dma: %#llx %s%s\n",
1256 i, count, (u64)sg->dma_address,
1257 param & BD_WRAP ? "wrap" : "",
1258 param & BD_INTR ? " intr" : "");
1259
1260 bd->mode.status = param;
1261 }
1262
1263 sdmac->num_bd = sg_len;
1264 sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
1265
1266 return &sdmac->desc;
1267 err_out:
1268 sdmac->status = DMA_ERROR;
1269 return NULL;
1270 }
1271
1272 static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
1273 struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
1274 size_t period_len, enum dma_transfer_direction direction,
1275 unsigned long flags)
1276 {
1277 struct sdma_channel *sdmac = to_sdma_chan(chan);
1278 struct sdma_engine *sdma = sdmac->sdma;
1279 int num_periods = buf_len / period_len;
1280 int channel = sdmac->channel;
1281 int ret, i = 0, buf = 0;
1282
1283 dev_dbg(sdma->dev, "%s channel: %d\n", __func__, channel);
1284
1285 if (sdmac->status == DMA_IN_PROGRESS)
1286 return NULL;
1287
1288 sdmac->status = DMA_IN_PROGRESS;
1289
1290 sdmac->buf_tail = 0;
1291 sdmac->period_len = period_len;
1292
1293 sdmac->flags |= IMX_DMA_SG_LOOP;
1294 sdmac->direction = direction;
1295 ret = sdma_load_context(sdmac);
1296 if (ret)
1297 goto err_out;
1298
1299 if (num_periods > NUM_BD) {
1300 dev_err(sdma->dev, "SDMA channel %d: maximum number of sg exceeded: %d > %d\n",
1301 channel, num_periods, NUM_BD);
1302 goto err_out;
1303 }
1304
1305 if (period_len > 0xffff) {
1306 dev_err(sdma->dev, "SDMA channel %d: maximum period size exceeded: %d > %d\n",
1307 channel, period_len, 0xffff);
1308 goto err_out;
1309 }
1310
1311 while (buf < buf_len) {
1312 struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
1313 int param;
1314
1315 bd->buffer_addr = dma_addr;
1316
1317 bd->mode.count = period_len;
1318
1319 if (sdmac->word_size > DMA_SLAVE_BUSWIDTH_4_BYTES)
1320 goto err_out;
1321 if (sdmac->word_size == DMA_SLAVE_BUSWIDTH_4_BYTES)
1322 bd->mode.command = 0;
1323 else
1324 bd->mode.command = sdmac->word_size;
1325
1326 param = BD_DONE | BD_EXTD | BD_CONT | BD_INTR;
1327 if (i + 1 == num_periods)
1328 param |= BD_WRAP;
1329
1330 dev_dbg(sdma->dev, "entry %d: count: %d dma: %#llx %s%s\n",
1331 i, period_len, (u64)dma_addr,
1332 param & BD_WRAP ? "wrap" : "",
1333 param & BD_INTR ? " intr" : "");
1334
1335 bd->mode.status = param;
1336
1337 dma_addr += period_len;
1338 buf += period_len;
1339
1340 i++;
1341 }
1342
1343 sdmac->num_bd = num_periods;
1344 sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
1345
1346 return &sdmac->desc;
1347 err_out:
1348 sdmac->status = DMA_ERROR;
1349 return NULL;
1350 }
1351
1352 static int sdma_config(struct dma_chan *chan,
1353 struct dma_slave_config *dmaengine_cfg)
1354 {
1355 struct sdma_channel *sdmac = to_sdma_chan(chan);
1356
1357 if (dmaengine_cfg->direction == DMA_DEV_TO_MEM) {
1358 sdmac->per_address = dmaengine_cfg->src_addr;
1359 sdmac->watermark_level = dmaengine_cfg->src_maxburst *
1360 dmaengine_cfg->src_addr_width;
1361 sdmac->word_size = dmaengine_cfg->src_addr_width;
1362 } else if (dmaengine_cfg->direction == DMA_DEV_TO_DEV) {
1363 sdmac->per_address2 = dmaengine_cfg->src_addr;
1364 sdmac->per_address = dmaengine_cfg->dst_addr;
1365 sdmac->watermark_level = dmaengine_cfg->src_maxburst &
1366 SDMA_WATERMARK_LEVEL_LWML;
1367 sdmac->watermark_level |= (dmaengine_cfg->dst_maxburst << 16) &
1368 SDMA_WATERMARK_LEVEL_HWML;
1369 sdmac->word_size = dmaengine_cfg->dst_addr_width;
1370 } else {
1371 sdmac->per_address = dmaengine_cfg->dst_addr;
1372 sdmac->watermark_level = dmaengine_cfg->dst_maxburst *
1373 dmaengine_cfg->dst_addr_width;
1374 sdmac->word_size = dmaengine_cfg->dst_addr_width;
1375 }
1376 sdmac->direction = dmaengine_cfg->direction;
1377 return sdma_config_channel(chan);
1378 }
1379
1380 static enum dma_status sdma_tx_status(struct dma_chan *chan,
1381 dma_cookie_t cookie,
1382 struct dma_tx_state *txstate)
1383 {
1384 struct sdma_channel *sdmac = to_sdma_chan(chan);
1385 u32 residue;
1386
1387 if (sdmac->flags & IMX_DMA_SG_LOOP)
1388 residue = (sdmac->num_bd - sdmac->buf_tail) *
1389 sdmac->period_len - sdmac->chn_real_count;
1390 else
1391 residue = sdmac->chn_count - sdmac->chn_real_count;
1392
1393 dma_set_tx_state(txstate, chan->completed_cookie, chan->cookie,
1394 residue);
1395
1396 return sdmac->status;
1397 }
1398
1399 static void sdma_issue_pending(struct dma_chan *chan)
1400 {
1401 struct sdma_channel *sdmac = to_sdma_chan(chan);
1402 struct sdma_engine *sdma = sdmac->sdma;
1403
1404 if (sdmac->status == DMA_IN_PROGRESS)
1405 sdma_enable_channel(sdma, sdmac->channel);
1406 }
1407
1408 #define SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V1 34
1409 #define SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V2 38
1410 #define SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V3 41
1411 #define SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V4 42
1412
1413 static void sdma_add_scripts(struct sdma_engine *sdma,
1414 const struct sdma_script_start_addrs *addr)
1415 {
1416 s32 *addr_arr = (u32 *)addr;
1417 s32 *saddr_arr = (u32 *)sdma->script_addrs;
1418 int i;
1419
1420 /* use the default firmware in ROM if missing external firmware */
1421 if (!sdma->script_number)
1422 sdma->script_number = SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V1;
1423
1424 for (i = 0; i < sdma->script_number; i++)
1425 if (addr_arr[i] > 0)
1426 saddr_arr[i] = addr_arr[i];
1427 }
1428
1429 static void sdma_load_firmware(const struct firmware *fw, void *context)
1430 {
1431 struct sdma_engine *sdma = context;
1432 const struct sdma_firmware_header *header;
1433 const struct sdma_script_start_addrs *addr;
1434 unsigned short *ram_code;
1435
1436 if (!fw) {
1437 dev_info(sdma->dev, "external firmware not found, using ROM firmware\n");
1438 /* In this case we just use the ROM firmware. */
1439 return;
1440 }
1441
1442 if (fw->size < sizeof(*header))
1443 goto err_firmware;
1444
1445 header = (struct sdma_firmware_header *)fw->data;
1446
1447 if (header->magic != SDMA_FIRMWARE_MAGIC)
1448 goto err_firmware;
1449 if (header->ram_code_start + header->ram_code_size > fw->size)
1450 goto err_firmware;
1451 switch (header->version_major) {
1452 case 1:
1453 sdma->script_number = SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V1;
1454 break;
1455 case 2:
1456 sdma->script_number = SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V2;
1457 break;
1458 case 3:
1459 sdma->script_number = SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V3;
1460 break;
1461 case 4:
1462 sdma->script_number = SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V4;
1463 break;
1464 default:
1465 dev_err(sdma->dev, "unknown firmware version\n");
1466 goto err_firmware;
1467 }
1468
1469 addr = (void *)header + header->script_addrs_start;
1470 ram_code = (void *)header + header->ram_code_start;
1471
1472 clk_enable(sdma->clk_ipg);
1473 clk_enable(sdma->clk_ahb);
1474 /* download the RAM image for SDMA */
1475 sdma_load_script(sdma, ram_code,
1476 header->ram_code_size,
1477 addr->ram_code_start_addr);
1478 clk_disable(sdma->clk_ipg);
1479 clk_disable(sdma->clk_ahb);
1480
1481 sdma_add_scripts(sdma, addr);
1482
1483 dev_info(sdma->dev, "loaded firmware %d.%d\n",
1484 header->version_major,
1485 header->version_minor);
1486
1487 err_firmware:
1488 release_firmware(fw);
1489 }
1490
1491 #define EVENT_REMAP_CELLS 3
1492
1493 static int sdma_event_remap(struct sdma_engine *sdma)
1494 {
1495 struct device_node *np = sdma->dev->of_node;
1496 struct device_node *gpr_np = of_parse_phandle(np, "gpr", 0);
1497 struct property *event_remap;
1498 struct regmap *gpr;
1499 char propname[] = "fsl,sdma-event-remap";
1500 u32 reg, val, shift, num_map, i;
1501 int ret = 0;
1502
1503 if (IS_ERR(np) || IS_ERR(gpr_np))
1504 goto out;
1505
1506 event_remap = of_find_property(np, propname, NULL);
1507 num_map = event_remap ? (event_remap->length / sizeof(u32)) : 0;
1508 if (!num_map) {
1509 dev_dbg(sdma->dev, "no event needs to be remapped\n");
1510 goto out;
1511 } else if (num_map % EVENT_REMAP_CELLS) {
1512 dev_err(sdma->dev, "the property %s must modulo %d\n",
1513 propname, EVENT_REMAP_CELLS);
1514 ret = -EINVAL;
1515 goto out;
1516 }
1517
1518 gpr = syscon_node_to_regmap(gpr_np);
1519 if (IS_ERR(gpr)) {
1520 dev_err(sdma->dev, "failed to get gpr regmap\n");
1521 ret = PTR_ERR(gpr);
1522 goto out;
1523 }
1524
1525 for (i = 0; i < num_map; i += EVENT_REMAP_CELLS) {
1526 ret = of_property_read_u32_index(np, propname, i, &reg);
1527 if (ret) {
1528 dev_err(sdma->dev, "failed to read property %s index %d\n",
1529 propname, i);
1530 goto out;
1531 }
1532
1533 ret = of_property_read_u32_index(np, propname, i + 1, &shift);
1534 if (ret) {
1535 dev_err(sdma->dev, "failed to read property %s index %d\n",
1536 propname, i + 1);
1537 goto out;
1538 }
1539
1540 ret = of_property_read_u32_index(np, propname, i + 2, &val);
1541 if (ret) {
1542 dev_err(sdma->dev, "failed to read property %s index %d\n",
1543 propname, i + 2);
1544 goto out;
1545 }
1546
1547 regmap_update_bits(gpr, reg, BIT(shift), val << shift);
1548 }
1549
1550 out:
1551 if (!IS_ERR(gpr_np))
1552 of_node_put(gpr_np);
1553
1554 return ret;
1555 }
1556
1557 static int sdma_get_firmware(struct sdma_engine *sdma,
1558 const char *fw_name)
1559 {
1560 int ret;
1561
1562 ret = request_firmware_nowait(THIS_MODULE,
1563 FW_ACTION_HOTPLUG, fw_name, sdma->dev,
1564 GFP_KERNEL, sdma, sdma_load_firmware);
1565
1566 return ret;
1567 }
1568
1569 static int sdma_init(struct sdma_engine *sdma)
1570 {
1571 int i, ret;
1572 dma_addr_t ccb_phys;
1573
1574 ret = clk_enable(sdma->clk_ipg);
1575 if (ret)
1576 return ret;
1577 ret = clk_enable(sdma->clk_ahb);
1578 if (ret)
1579 goto disable_clk_ipg;
1580
1581 /* Be sure SDMA has not started yet */
1582 writel_relaxed(0, sdma->regs + SDMA_H_C0PTR);
1583
1584 sdma->channel_control = dma_alloc_coherent(NULL,
1585 MAX_DMA_CHANNELS * sizeof (struct sdma_channel_control) +
1586 sizeof(struct sdma_context_data),
1587 &ccb_phys, GFP_KERNEL);
1588
1589 if (!sdma->channel_control) {
1590 ret = -ENOMEM;
1591 goto err_dma_alloc;
1592 }
1593
1594 sdma->context = (void *)sdma->channel_control +
1595 MAX_DMA_CHANNELS * sizeof (struct sdma_channel_control);
1596 sdma->context_phys = ccb_phys +
1597 MAX_DMA_CHANNELS * sizeof (struct sdma_channel_control);
1598
1599 /* Zero-out the CCB structures array just allocated */
1600 memset(sdma->channel_control, 0,
1601 MAX_DMA_CHANNELS * sizeof (struct sdma_channel_control));
1602
1603 /* disable all channels */
1604 for (i = 0; i < sdma->drvdata->num_events; i++)
1605 writel_relaxed(0, sdma->regs + chnenbl_ofs(sdma, i));
1606
1607 /* All channels have priority 0 */
1608 for (i = 0; i < MAX_DMA_CHANNELS; i++)
1609 writel_relaxed(0, sdma->regs + SDMA_CHNPRI_0 + i * 4);
1610
1611 ret = sdma_request_channel(&sdma->channel[0]);
1612 if (ret)
1613 goto err_dma_alloc;
1614
1615 sdma_config_ownership(&sdma->channel[0], false, true, false);
1616
1617 /* Set Command Channel (Channel Zero) */
1618 writel_relaxed(0x4050, sdma->regs + SDMA_CHN0ADDR);
1619
1620 /* Set bits of CONFIG register but with static context switching */
1621 /* FIXME: Check whether to set ACR bit depending on clock ratios */
1622 writel_relaxed(0, sdma->regs + SDMA_H_CONFIG);
1623
1624 writel_relaxed(ccb_phys, sdma->regs + SDMA_H_C0PTR);
1625
1626 /* Initializes channel's priorities */
1627 sdma_set_channel_priority(&sdma->channel[0], 7);
1628
1629 clk_disable(sdma->clk_ipg);
1630 clk_disable(sdma->clk_ahb);
1631
1632 return 0;
1633
1634 err_dma_alloc:
1635 clk_disable(sdma->clk_ahb);
1636 disable_clk_ipg:
1637 clk_disable(sdma->clk_ipg);
1638 dev_err(sdma->dev, "initialisation failed with %d\n", ret);
1639 return ret;
1640 }
1641
1642 static bool sdma_filter_fn(struct dma_chan *chan, void *fn_param)
1643 {
1644 struct sdma_channel *sdmac = to_sdma_chan(chan);
1645 struct imx_dma_data *data = fn_param;
1646
1647 if (!imx_dma_is_general_purpose(chan))
1648 return false;
1649
1650 sdmac->data = *data;
1651 chan->private = &sdmac->data;
1652
1653 return true;
1654 }
1655
1656 static struct dma_chan *sdma_xlate(struct of_phandle_args *dma_spec,
1657 struct of_dma *ofdma)
1658 {
1659 struct sdma_engine *sdma = ofdma->of_dma_data;
1660 dma_cap_mask_t mask = sdma->dma_device.cap_mask;
1661 struct imx_dma_data data;
1662
1663 if (dma_spec->args_count != 3)
1664 return NULL;
1665
1666 data.dma_request = dma_spec->args[0];
1667 data.peripheral_type = dma_spec->args[1];
1668 data.priority = dma_spec->args[2];
1669 /*
1670 * init dma_request2 to zero, which is not used by the dts.
1671 * For P2P, dma_request2 is init from dma_request_channel(),
1672 * chan->private will point to the imx_dma_data, and in
1673 * device_alloc_chan_resources(), imx_dma_data.dma_request2 will
1674 * be set to sdmac->event_id1.
1675 */
1676 data.dma_request2 = 0;
1677
1678 return dma_request_channel(mask, sdma_filter_fn, &data);
1679 }
1680
1681 static int sdma_probe(struct platform_device *pdev)
1682 {
1683 const struct of_device_id *of_id =
1684 of_match_device(sdma_dt_ids, &pdev->dev);
1685 struct device_node *np = pdev->dev.of_node;
1686 struct device_node *spba_bus;
1687 const char *fw_name;
1688 int ret;
1689 int irq;
1690 struct resource *iores;
1691 struct resource spba_res;
1692 struct sdma_platform_data *pdata = dev_get_platdata(&pdev->dev);
1693 int i;
1694 struct sdma_engine *sdma;
1695 s32 *saddr_arr;
1696 const struct sdma_driver_data *drvdata = NULL;
1697
1698 if (of_id)
1699 drvdata = of_id->data;
1700 else if (pdev->id_entry)
1701 drvdata = (void *)pdev->id_entry->driver_data;
1702
1703 if (!drvdata) {
1704 dev_err(&pdev->dev, "unable to find driver data\n");
1705 return -EINVAL;
1706 }
1707
1708 ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
1709 if (ret)
1710 return ret;
1711
1712 sdma = devm_kzalloc(&pdev->dev, sizeof(*sdma), GFP_KERNEL);
1713 if (!sdma)
1714 return -ENOMEM;
1715
1716 spin_lock_init(&sdma->channel_0_lock);
1717
1718 sdma->dev = &pdev->dev;
1719 sdma->drvdata = drvdata;
1720
1721 irq = platform_get_irq(pdev, 0);
1722 if (irq < 0)
1723 return irq;
1724
1725 iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1726 sdma->regs = devm_ioremap_resource(&pdev->dev, iores);
1727 if (IS_ERR(sdma->regs))
1728 return PTR_ERR(sdma->regs);
1729
1730 sdma->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1731 if (IS_ERR(sdma->clk_ipg))
1732 return PTR_ERR(sdma->clk_ipg);
1733
1734 sdma->clk_ahb = devm_clk_get(&pdev->dev, "ahb");
1735 if (IS_ERR(sdma->clk_ahb))
1736 return PTR_ERR(sdma->clk_ahb);
1737
1738 clk_prepare(sdma->clk_ipg);
1739 clk_prepare(sdma->clk_ahb);
1740
1741 ret = devm_request_irq(&pdev->dev, irq, sdma_int_handler, 0, "sdma",
1742 sdma);
1743 if (ret)
1744 return ret;
1745
1746 sdma->irq = irq;
1747
1748 sdma->script_addrs = kzalloc(sizeof(*sdma->script_addrs), GFP_KERNEL);
1749 if (!sdma->script_addrs)
1750 return -ENOMEM;
1751
1752 /* initially no scripts available */
1753 saddr_arr = (s32 *)sdma->script_addrs;
1754 for (i = 0; i < SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V1; i++)
1755 saddr_arr[i] = -EINVAL;
1756
1757 dma_cap_set(DMA_SLAVE, sdma->dma_device.cap_mask);
1758 dma_cap_set(DMA_CYCLIC, sdma->dma_device.cap_mask);
1759
1760 INIT_LIST_HEAD(&sdma->dma_device.channels);
1761 /* Initialize channel parameters */
1762 for (i = 0; i < MAX_DMA_CHANNELS; i++) {
1763 struct sdma_channel *sdmac = &sdma->channel[i];
1764
1765 sdmac->sdma = sdma;
1766 spin_lock_init(&sdmac->lock);
1767
1768 sdmac->chan.device = &sdma->dma_device;
1769 dma_cookie_init(&sdmac->chan);
1770 sdmac->channel = i;
1771
1772 tasklet_init(&sdmac->tasklet, mxc_sdma_handle_channel_normal,
1773 (unsigned long) sdmac);
1774 /*
1775 * Add the channel to the DMAC list. Do not add channel 0 though
1776 * because we need it internally in the SDMA driver. This also means
1777 * that channel 0 in dmaengine counting matches sdma channel 1.
1778 */
1779 if (i)
1780 list_add_tail(&sdmac->chan.device_node,
1781 &sdma->dma_device.channels);
1782 }
1783
1784 ret = sdma_init(sdma);
1785 if (ret)
1786 goto err_init;
1787
1788 ret = sdma_event_remap(sdma);
1789 if (ret)
1790 goto err_init;
1791
1792 if (sdma->drvdata->script_addrs)
1793 sdma_add_scripts(sdma, sdma->drvdata->script_addrs);
1794 if (pdata && pdata->script_addrs)
1795 sdma_add_scripts(sdma, pdata->script_addrs);
1796
1797 if (pdata) {
1798 ret = sdma_get_firmware(sdma, pdata->fw_name);
1799 if (ret)
1800 dev_warn(&pdev->dev, "failed to get firmware from platform data\n");
1801 } else {
1802 /*
1803 * Because that device tree does not encode ROM script address,
1804 * the RAM script in firmware is mandatory for device tree
1805 * probe, otherwise it fails.
1806 */
1807 ret = of_property_read_string(np, "fsl,sdma-ram-script-name",
1808 &fw_name);
1809 if (ret)
1810 dev_warn(&pdev->dev, "failed to get firmware name\n");
1811 else {
1812 ret = sdma_get_firmware(sdma, fw_name);
1813 if (ret)
1814 dev_warn(&pdev->dev, "failed to get firmware from device tree\n");
1815 }
1816 }
1817
1818 sdma->dma_device.dev = &pdev->dev;
1819
1820 sdma->dma_device.device_alloc_chan_resources = sdma_alloc_chan_resources;
1821 sdma->dma_device.device_free_chan_resources = sdma_free_chan_resources;
1822 sdma->dma_device.device_tx_status = sdma_tx_status;
1823 sdma->dma_device.device_prep_slave_sg = sdma_prep_slave_sg;
1824 sdma->dma_device.device_prep_dma_cyclic = sdma_prep_dma_cyclic;
1825 sdma->dma_device.device_config = sdma_config;
1826 sdma->dma_device.device_terminate_all = sdma_disable_channel;
1827 sdma->dma_device.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
1828 sdma->dma_device.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
1829 sdma->dma_device.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1830 sdma->dma_device.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1831 sdma->dma_device.device_issue_pending = sdma_issue_pending;
1832 sdma->dma_device.dev->dma_parms = &sdma->dma_parms;
1833 dma_set_max_seg_size(sdma->dma_device.dev, 65535);
1834
1835 platform_set_drvdata(pdev, sdma);
1836
1837 ret = dma_async_device_register(&sdma->dma_device);
1838 if (ret) {
1839 dev_err(&pdev->dev, "unable to register\n");
1840 goto err_init;
1841 }
1842
1843 if (np) {
1844 ret = of_dma_controller_register(np, sdma_xlate, sdma);
1845 if (ret) {
1846 dev_err(&pdev->dev, "failed to register controller\n");
1847 goto err_register;
1848 }
1849
1850 spba_bus = of_find_compatible_node(NULL, NULL, "fsl,spba-bus");
1851 ret = of_address_to_resource(spba_bus, 0, &spba_res);
1852 if (!ret) {
1853 sdma->spba_start_addr = spba_res.start;
1854 sdma->spba_end_addr = spba_res.end;
1855 }
1856 of_node_put(spba_bus);
1857 }
1858
1859 return 0;
1860
1861 err_register:
1862 dma_async_device_unregister(&sdma->dma_device);
1863 err_init:
1864 kfree(sdma->script_addrs);
1865 return ret;
1866 }
1867
1868 static int sdma_remove(struct platform_device *pdev)
1869 {
1870 struct sdma_engine *sdma = platform_get_drvdata(pdev);
1871 int i;
1872
1873 devm_free_irq(&pdev->dev, sdma->irq, sdma);
1874 dma_async_device_unregister(&sdma->dma_device);
1875 kfree(sdma->script_addrs);
1876 /* Kill the tasklet */
1877 for (i = 0; i < MAX_DMA_CHANNELS; i++) {
1878 struct sdma_channel *sdmac = &sdma->channel[i];
1879
1880 tasklet_kill(&sdmac->tasklet);
1881 }
1882
1883 platform_set_drvdata(pdev, NULL);
1884 return 0;
1885 }
1886
1887 static struct platform_driver sdma_driver = {
1888 .driver = {
1889 .name = "imx-sdma",
1890 .of_match_table = sdma_dt_ids,
1891 },
1892 .id_table = sdma_devtypes,
1893 .remove = sdma_remove,
1894 .probe = sdma_probe,
1895 };
1896
1897 module_platform_driver(sdma_driver);
1898
1899 MODULE_AUTHOR("Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>");
1900 MODULE_DESCRIPTION("i.MX SDMA driver");
1901 MODULE_LICENSE("GPL");
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