1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * bcm2835 sdhost driver.
4 *
5 * The 2835 has two SD controllers: The Arasan sdhci controller
6 * (supported by the iproc driver) and a custom sdhost controller
7 * (supported by this driver).
8 *
9 * The sdhci controller supports both sdcard and sdio. The sdhost
10 * controller supports the sdcard only, but has better performance.
11 * Also note that the rpi3 has sdio wifi, so driving the sdcard with
12 * the sdhost controller allows to use the sdhci controller for wifi
13 * support.
14 *
15 * The configuration is done by devicetree via pin muxing. Both
16 * SD controller are available on the same pins (2 pin groups = pin 22
17 * to 27 + pin 48 to 53). So it's possible to use both SD controllers
18 * at the same time with different pin groups.
19 *
20 * Author: Phil Elwell <[email protected]>
21 * Copyright (C) 2015-2016 Raspberry Pi (Trading) Ltd.
22 *
23 * Based on
24 * mmc-bcm2835.c by Gellert Weisz
25 * which is, in turn, based on
26 * sdhci-bcm2708.c by Broadcom
27 * sdhci-bcm2835.c by Stephen Warren and Oleksandr Tymoshenko
28 * sdhci.c and sdhci-pci.c by Pierre Ossman
29 */
30 #include <linux/clk.h>
31 #include <linux/delay.h>
32 #include <linux/device.h>
33 #include <linux/dmaengine.h>
34 #include <linux/dma-mapping.h>
35 #include <linux/err.h>
36 #include <linux/highmem.h>
37 #include <linux/interrupt.h>
38 #include <linux/io.h>
39 #include <linux/iopoll.h>
40 #include <linux/module.h>
41 #include <linux/of_address.h>
42 #include <linux/of_irq.h>
43 #include <linux/platform_device.h>
44 #include <linux/scatterlist.h>
45 #include <linux/time.h>
46 #include <linux/workqueue.h>
47
48 #include <linux/mmc/host.h>
49 #include <linux/mmc/mmc.h>
50 #include <linux/mmc/sd.h>
51
52 #define SDCMD 0x00 /* Command to SD card - 16 R/W */
53 #define SDARG 0x04 /* Argument to SD card - 32 R/W */
54 #define SDTOUT 0x08 /* Start value for timeout counter - 32 R/W */
55 #define SDCDIV 0x0c /* Start value for clock divider - 11 R/W */
56 #define SDRSP0 0x10 /* SD card response (31:0) - 32 R */
57 #define SDRSP1 0x14 /* SD card response (63:32) - 32 R */
58 #define SDRSP2 0x18 /* SD card response (95:64) - 32 R */
59 #define SDRSP3 0x1c /* SD card response (127:96) - 32 R */
60 #define SDHSTS 0x20 /* SD host status - 11 R/W */
61 #define SDVDD 0x30 /* SD card power control - 1 R/W */
62 #define SDEDM 0x34 /* Emergency Debug Mode - 13 R/W */
63 #define SDHCFG 0x38 /* Host configuration - 2 R/W */
64 #define SDHBCT 0x3c /* Host byte count (debug) - 32 R/W */
65 #define SDDATA 0x40 /* Data to/from SD card - 32 R/W */
66 #define SDHBLC 0x50 /* Host block count (SDIO/SDHC) - 9 R/W */
67
68 #define SDCMD_NEW_FLAG 0x8000
69 #define SDCMD_FAIL_FLAG 0x4000
70 #define SDCMD_BUSYWAIT 0x800
71 #define SDCMD_NO_RESPONSE 0x400
72 #define SDCMD_LONG_RESPONSE 0x200
73 #define SDCMD_WRITE_CMD 0x80
74 #define SDCMD_READ_CMD 0x40
75 #define SDCMD_CMD_MASK 0x3f
76
77 #define SDCDIV_MAX_CDIV 0x7ff
78
79 #define SDHSTS_BUSY_IRPT 0x400
80 #define SDHSTS_BLOCK_IRPT 0x200
81 #define SDHSTS_SDIO_IRPT 0x100
82 #define SDHSTS_REW_TIME_OUT 0x80
83 #define SDHSTS_CMD_TIME_OUT 0x40
84 #define SDHSTS_CRC16_ERROR 0x20
85 #define SDHSTS_CRC7_ERROR 0x10
86 #define SDHSTS_FIFO_ERROR 0x08
87 /* Reserved */
88 /* Reserved */
89 #define SDHSTS_DATA_FLAG 0x01
90
91 #define SDHSTS_TRANSFER_ERROR_MASK (SDHSTS_CRC7_ERROR | \
92 SDHSTS_CRC16_ERROR | \
93 SDHSTS_REW_TIME_OUT | \
94 SDHSTS_FIFO_ERROR)
95
96 #define SDHSTS_ERROR_MASK (SDHSTS_CMD_TIME_OUT | \
97 SDHSTS_TRANSFER_ERROR_MASK)
98
99 #define SDHCFG_BUSY_IRPT_EN BIT(10)
100 #define SDHCFG_BLOCK_IRPT_EN BIT(8)
101 #define SDHCFG_SDIO_IRPT_EN BIT(5)
102 #define SDHCFG_DATA_IRPT_EN BIT(4)
103 #define SDHCFG_SLOW_CARD BIT(3)
104 #define SDHCFG_WIDE_EXT_BUS BIT(2)
105 #define SDHCFG_WIDE_INT_BUS BIT(1)
106 #define SDHCFG_REL_CMD_LINE BIT(0)
107
108 #define SDVDD_POWER_OFF 0
109 #define SDVDD_POWER_ON 1
110
111 #define SDEDM_FORCE_DATA_MODE BIT(19)
112 #define SDEDM_CLOCK_PULSE BIT(20)
113 #define SDEDM_BYPASS BIT(21)
114
115 #define SDEDM_WRITE_THRESHOLD_SHIFT 9
116 #define SDEDM_READ_THRESHOLD_SHIFT 14
117 #define SDEDM_THRESHOLD_MASK 0x1f
118
119 #define SDEDM_FSM_MASK 0xf
120 #define SDEDM_FSM_IDENTMODE 0x0
121 #define SDEDM_FSM_DATAMODE 0x1
122 #define SDEDM_FSM_READDATA 0x2
123 #define SDEDM_FSM_WRITEDATA 0x3
124 #define SDEDM_FSM_READWAIT 0x4
125 #define SDEDM_FSM_READCRC 0x5
126 #define SDEDM_FSM_WRITECRC 0x6
127 #define SDEDM_FSM_WRITEWAIT1 0x7
128 #define SDEDM_FSM_POWERDOWN 0x8
129 #define SDEDM_FSM_POWERUP 0x9
130 #define SDEDM_FSM_WRITESTART1 0xa
131 #define SDEDM_FSM_WRITESTART2 0xb
132 #define SDEDM_FSM_GENPULSES 0xc
133 #define SDEDM_FSM_WRITEWAIT2 0xd
134 #define SDEDM_FSM_STARTPOWDOWN 0xf
135
136 #define SDDATA_FIFO_WORDS 16
137
138 #define FIFO_READ_THRESHOLD 4
139 #define FIFO_WRITE_THRESHOLD 4
140 #define SDDATA_FIFO_PIO_BURST 8
141
142 #define PIO_THRESHOLD 1 /* Maximum block count for PIO (0 = always DMA) */
143
144 struct bcm2835_host {
145 spinlock_t lock;
146 struct mutex mutex;
147
148 void __iomem *ioaddr;
149 u32 phys_addr;
150
151 struct clk *clk;
152 struct platform_device *pdev;
153
154 unsigned int clock; /* Current clock speed */
155 unsigned int max_clk; /* Max possible freq */
156 struct work_struct dma_work;
157 struct delayed_work timeout_work; /* Timer for timeouts */
158 struct sg_mapping_iter sg_miter; /* SG state for PIO */
159 unsigned int blocks; /* remaining PIO blocks */
160 int irq; /* Device IRQ */
161
162 u32 ns_per_fifo_word;
163
164 /* cached registers */
165 u32 hcfg;
166 u32 cdiv;
167
168 struct mmc_request *mrq; /* Current request */
169 struct mmc_command *cmd; /* Current command */
170 struct mmc_data *data; /* Current data request */
171 bool data_complete:1;/* Data finished before cmd */
172 bool use_busy:1; /* Wait for busy interrupt */
173 bool use_sbc:1; /* Send CMD23 */
174
175 /* for threaded irq handler */
176 bool irq_block;
177 bool irq_busy;
178 bool irq_data;
179
180 /* DMA part */
181 struct dma_chan *dma_chan_rxtx;
182 struct dma_chan *dma_chan;
183 struct dma_slave_config dma_cfg_rx;
184 struct dma_slave_config dma_cfg_tx;
185 struct dma_async_tx_descriptor *dma_desc;
186 u32 dma_dir;
187 u32 drain_words;
188 struct page *drain_page;
189 u32 drain_offset;
190 bool use_dma;
191 };
192
bcm2835_dumpcmd(struct bcm2835_host * host,struct mmc_command * cmd,const char * label)193 static void bcm2835_dumpcmd(struct bcm2835_host *host, struct mmc_command *cmd,
194 const char *label)
195 {
196 struct device *dev = &host->pdev->dev;
197
198 if (!cmd)
199 return;
200
201 dev_dbg(dev, "%c%s op %d arg 0x%x flags 0x%x - resp %08x %08x %08x %08x, err %d\n",
202 (cmd == host->cmd) ? '>' : ' ',
203 label, cmd->opcode, cmd->arg, cmd->flags,
204 cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3],
205 cmd->error);
206 }
207
bcm2835_dumpregs(struct bcm2835_host * host)208 static void bcm2835_dumpregs(struct bcm2835_host *host)
209 {
210 struct mmc_request *mrq = host->mrq;
211 struct device *dev = &host->pdev->dev;
212
213 if (mrq) {
214 bcm2835_dumpcmd(host, mrq->sbc, "sbc");
215 bcm2835_dumpcmd(host, mrq->cmd, "cmd");
216 if (mrq->data) {
217 dev_dbg(dev, "data blocks %x blksz %x - err %d\n",
218 mrq->data->blocks,
219 mrq->data->blksz,
220 mrq->data->error);
221 }
222 bcm2835_dumpcmd(host, mrq->stop, "stop");
223 }
224
225 dev_dbg(dev, "=========== REGISTER DUMP ===========\n");
226 dev_dbg(dev, "SDCMD 0x%08x\n", readl(host->ioaddr + SDCMD));
227 dev_dbg(dev, "SDARG 0x%08x\n", readl(host->ioaddr + SDARG));
228 dev_dbg(dev, "SDTOUT 0x%08x\n", readl(host->ioaddr + SDTOUT));
229 dev_dbg(dev, "SDCDIV 0x%08x\n", readl(host->ioaddr + SDCDIV));
230 dev_dbg(dev, "SDRSP0 0x%08x\n", readl(host->ioaddr + SDRSP0));
231 dev_dbg(dev, "SDRSP1 0x%08x\n", readl(host->ioaddr + SDRSP1));
232 dev_dbg(dev, "SDRSP2 0x%08x\n", readl(host->ioaddr + SDRSP2));
233 dev_dbg(dev, "SDRSP3 0x%08x\n", readl(host->ioaddr + SDRSP3));
234 dev_dbg(dev, "SDHSTS 0x%08x\n", readl(host->ioaddr + SDHSTS));
235 dev_dbg(dev, "SDVDD 0x%08x\n", readl(host->ioaddr + SDVDD));
236 dev_dbg(dev, "SDEDM 0x%08x\n", readl(host->ioaddr + SDEDM));
237 dev_dbg(dev, "SDHCFG 0x%08x\n", readl(host->ioaddr + SDHCFG));
238 dev_dbg(dev, "SDHBCT 0x%08x\n", readl(host->ioaddr + SDHBCT));
239 dev_dbg(dev, "SDHBLC 0x%08x\n", readl(host->ioaddr + SDHBLC));
240 dev_dbg(dev, "===========================================\n");
241 }
242
bcm2835_reset_internal(struct bcm2835_host * host)243 static void bcm2835_reset_internal(struct bcm2835_host *host)
244 {
245 u32 temp;
246
247 writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD);
248 writel(0, host->ioaddr + SDCMD);
249 writel(0, host->ioaddr + SDARG);
250 writel(0xf00000, host->ioaddr + SDTOUT);
251 writel(0, host->ioaddr + SDCDIV);
252 writel(0x7f8, host->ioaddr + SDHSTS); /* Write 1s to clear */
253 writel(0, host->ioaddr + SDHCFG);
254 writel(0, host->ioaddr + SDHBCT);
255 writel(0, host->ioaddr + SDHBLC);
256
257 /* Limit fifo usage due to silicon bug */
258 temp = readl(host->ioaddr + SDEDM);
259 temp &= ~((SDEDM_THRESHOLD_MASK << SDEDM_READ_THRESHOLD_SHIFT) |
260 (SDEDM_THRESHOLD_MASK << SDEDM_WRITE_THRESHOLD_SHIFT));
261 temp |= (FIFO_READ_THRESHOLD << SDEDM_READ_THRESHOLD_SHIFT) |
262 (FIFO_WRITE_THRESHOLD << SDEDM_WRITE_THRESHOLD_SHIFT);
263 writel(temp, host->ioaddr + SDEDM);
264 msleep(20);
265 writel(SDVDD_POWER_ON, host->ioaddr + SDVDD);
266 msleep(20);
267 host->clock = 0;
268 writel(host->hcfg, host->ioaddr + SDHCFG);
269 writel(host->cdiv, host->ioaddr + SDCDIV);
270 }
271
bcm2835_reset(struct mmc_host * mmc)272 static void bcm2835_reset(struct mmc_host *mmc)
273 {
274 struct bcm2835_host *host = mmc_priv(mmc);
275
276 if (host->dma_chan)
277 dmaengine_terminate_sync(host->dma_chan);
278 host->dma_chan = NULL;
279 bcm2835_reset_internal(host);
280 }
281
282 static void bcm2835_finish_command(struct bcm2835_host *host);
283
bcm2835_wait_transfer_complete(struct bcm2835_host * host)284 static void bcm2835_wait_transfer_complete(struct bcm2835_host *host)
285 {
286 int timediff;
287 u32 alternate_idle;
288
289 alternate_idle = (host->mrq->data->flags & MMC_DATA_READ) ?
290 SDEDM_FSM_READWAIT : SDEDM_FSM_WRITESTART1;
291
292 timediff = 0;
293
294 while (1) {
295 u32 edm, fsm;
296
297 edm = readl(host->ioaddr + SDEDM);
298 fsm = edm & SDEDM_FSM_MASK;
299
300 if ((fsm == SDEDM_FSM_IDENTMODE) ||
301 (fsm == SDEDM_FSM_DATAMODE))
302 break;
303 if (fsm == alternate_idle) {
304 writel(edm | SDEDM_FORCE_DATA_MODE,
305 host->ioaddr + SDEDM);
306 break;
307 }
308
309 timediff++;
310 if (timediff == 100000) {
311 dev_err(&host->pdev->dev,
312 "wait_transfer_complete - still waiting after %d retries\n",
313 timediff);
314 bcm2835_dumpregs(host);
315 host->mrq->data->error = -ETIMEDOUT;
316 return;
317 }
318 cpu_relax();
319 }
320 }
321
bcm2835_dma_complete(void * param)322 static void bcm2835_dma_complete(void *param)
323 {
324 struct bcm2835_host *host = param;
325
326 schedule_work(&host->dma_work);
327 }
328
bcm2835_transfer_block_pio(struct bcm2835_host * host,bool is_read)329 static void bcm2835_transfer_block_pio(struct bcm2835_host *host, bool is_read)
330 {
331 size_t blksize;
332 unsigned long wait_max;
333
334 blksize = host->data->blksz;
335
336 wait_max = jiffies + msecs_to_jiffies(500);
337
338 while (blksize) {
339 int copy_words;
340 u32 hsts = 0;
341 size_t len;
342 u32 *buf;
343
344 if (!sg_miter_next(&host->sg_miter)) {
345 host->data->error = -EINVAL;
346 break;
347 }
348
349 len = min(host->sg_miter.length, blksize);
350 if (len % 4) {
351 host->data->error = -EINVAL;
352 break;
353 }
354
355 blksize -= len;
356 host->sg_miter.consumed = len;
357
358 buf = (u32 *)host->sg_miter.addr;
359
360 copy_words = len / 4;
361
362 while (copy_words) {
363 int burst_words, words;
364 u32 edm;
365
366 burst_words = min(SDDATA_FIFO_PIO_BURST, copy_words);
367 edm = readl(host->ioaddr + SDEDM);
368 if (is_read)
369 words = ((edm >> 4) & 0x1f);
370 else
371 words = SDDATA_FIFO_WORDS - ((edm >> 4) & 0x1f);
372
373 if (words < burst_words) {
374 int fsm_state = (edm & SDEDM_FSM_MASK);
375 struct device *dev = &host->pdev->dev;
376
377 if ((is_read &&
378 (fsm_state != SDEDM_FSM_READDATA &&
379 fsm_state != SDEDM_FSM_READWAIT &&
380 fsm_state != SDEDM_FSM_READCRC)) ||
381 (!is_read &&
382 (fsm_state != SDEDM_FSM_WRITEDATA &&
383 fsm_state != SDEDM_FSM_WRITESTART1 &&
384 fsm_state != SDEDM_FSM_WRITESTART2))) {
385 hsts = readl(host->ioaddr + SDHSTS);
386 dev_err(dev, "fsm %x, hsts %08x\n",
387 fsm_state, hsts);
388 if (hsts & SDHSTS_ERROR_MASK)
389 break;
390 }
391
392 if (time_after(jiffies, wait_max)) {
393 dev_err(dev, "PIO %s timeout - EDM %08x\n",
394 is_read ? "read" : "write",
395 edm);
396 hsts = SDHSTS_REW_TIME_OUT;
397 break;
398 }
399 ndelay((burst_words - words) *
400 host->ns_per_fifo_word);
401 continue;
402 } else if (words > copy_words) {
403 words = copy_words;
404 }
405
406 copy_words -= words;
407
408 while (words) {
409 if (is_read)
410 *(buf++) = readl(host->ioaddr + SDDATA);
411 else
412 writel(*(buf++), host->ioaddr + SDDATA);
413 words--;
414 }
415 }
416
417 if (hsts & SDHSTS_ERROR_MASK)
418 break;
419 }
420
421 sg_miter_stop(&host->sg_miter);
422 }
423
bcm2835_transfer_pio(struct bcm2835_host * host)424 static void bcm2835_transfer_pio(struct bcm2835_host *host)
425 {
426 struct device *dev = &host->pdev->dev;
427 u32 sdhsts;
428 bool is_read;
429
430 is_read = (host->data->flags & MMC_DATA_READ) != 0;
431 bcm2835_transfer_block_pio(host, is_read);
432
433 sdhsts = readl(host->ioaddr + SDHSTS);
434 if (sdhsts & (SDHSTS_CRC16_ERROR |
435 SDHSTS_CRC7_ERROR |
436 SDHSTS_FIFO_ERROR)) {
437 dev_err(dev, "%s transfer error - HSTS %08x\n",
438 is_read ? "read" : "write", sdhsts);
439 host->data->error = -EILSEQ;
440 } else if ((sdhsts & (SDHSTS_CMD_TIME_OUT |
441 SDHSTS_REW_TIME_OUT))) {
442 dev_err(dev, "%s timeout error - HSTS %08x\n",
443 is_read ? "read" : "write", sdhsts);
444 host->data->error = -ETIMEDOUT;
445 }
446 }
447
448 static
bcm2835_prepare_dma(struct bcm2835_host * host,struct mmc_data * data)449 void bcm2835_prepare_dma(struct bcm2835_host *host, struct mmc_data *data)
450 {
451 int sg_len, dir_data, dir_slave;
452 struct dma_async_tx_descriptor *desc = NULL;
453 struct dma_chan *dma_chan;
454
455 dma_chan = host->dma_chan_rxtx;
456 if (data->flags & MMC_DATA_READ) {
457 dir_data = DMA_FROM_DEVICE;
458 dir_slave = DMA_DEV_TO_MEM;
459 } else {
460 dir_data = DMA_TO_DEVICE;
461 dir_slave = DMA_MEM_TO_DEV;
462 }
463
464 /* The block doesn't manage the FIFO DREQs properly for
465 * multi-block transfers, so don't attempt to DMA the final
466 * few words. Unfortunately this requires the final sg entry
467 * to be trimmed. N.B. This code demands that the overspill
468 * is contained in a single sg entry.
469 */
470
471 host->drain_words = 0;
472 if ((data->blocks > 1) && (dir_data == DMA_FROM_DEVICE)) {
473 struct scatterlist *sg;
474 u32 len;
475 int i;
476
477 len = min((u32)(FIFO_READ_THRESHOLD - 1) * 4,
478 (u32)data->blocks * data->blksz);
479
480 for_each_sg(data->sg, sg, data->sg_len, i) {
481 if (sg_is_last(sg)) {
482 WARN_ON(sg->length < len);
483 sg->length -= len;
484 host->drain_page = sg_page(sg);
485 host->drain_offset = sg->offset + sg->length;
486 }
487 }
488 host->drain_words = len / 4;
489 }
490
491 /* The parameters have already been validated, so this will not fail */
492 (void)dmaengine_slave_config(dma_chan,
493 (dir_data == DMA_FROM_DEVICE) ?
494 &host->dma_cfg_rx :
495 &host->dma_cfg_tx);
496
497 sg_len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len,
498 dir_data);
499 if (!sg_len)
500 return;
501
502 desc = dmaengine_prep_slave_sg(dma_chan, data->sg, sg_len, dir_slave,
503 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
504
505 if (!desc) {
506 dma_unmap_sg(dma_chan->device->dev, data->sg, sg_len, dir_data);
507 return;
508 }
509
510 desc->callback = bcm2835_dma_complete;
511 desc->callback_param = host;
512 host->dma_desc = desc;
513 host->dma_chan = dma_chan;
514 host->dma_dir = dir_data;
515 }
516
bcm2835_start_dma(struct bcm2835_host * host)517 static void bcm2835_start_dma(struct bcm2835_host *host)
518 {
519 dmaengine_submit(host->dma_desc);
520 dma_async_issue_pending(host->dma_chan);
521 }
522
bcm2835_set_transfer_irqs(struct bcm2835_host * host)523 static void bcm2835_set_transfer_irqs(struct bcm2835_host *host)
524 {
525 u32 all_irqs = SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN |
526 SDHCFG_BUSY_IRPT_EN;
527
528 if (host->dma_desc) {
529 host->hcfg = (host->hcfg & ~all_irqs) |
530 SDHCFG_BUSY_IRPT_EN;
531 } else {
532 host->hcfg = (host->hcfg & ~all_irqs) |
533 SDHCFG_DATA_IRPT_EN |
534 SDHCFG_BUSY_IRPT_EN;
535 }
536
537 writel(host->hcfg, host->ioaddr + SDHCFG);
538 }
539
540 static
bcm2835_prepare_data(struct bcm2835_host * host,struct mmc_command * cmd)541 void bcm2835_prepare_data(struct bcm2835_host *host, struct mmc_command *cmd)
542 {
543 struct mmc_data *data = cmd->data;
544
545 WARN_ON(host->data);
546
547 host->data = data;
548 if (!data)
549 return;
550
551 host->data_complete = false;
552 host->data->bytes_xfered = 0;
553
554 if (!host->dma_desc) {
555 /* Use PIO */
556 int flags = SG_MITER_ATOMIC;
557
558 if (data->flags & MMC_DATA_READ)
559 flags |= SG_MITER_TO_SG;
560 else
561 flags |= SG_MITER_FROM_SG;
562 sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags);
563 host->blocks = data->blocks;
564 }
565
566 bcm2835_set_transfer_irqs(host);
567
568 writel(data->blksz, host->ioaddr + SDHBCT);
569 writel(data->blocks, host->ioaddr + SDHBLC);
570 }
571
bcm2835_read_wait_sdcmd(struct bcm2835_host * host,u32 max_ms)572 static u32 bcm2835_read_wait_sdcmd(struct bcm2835_host *host, u32 max_ms)
573 {
574 struct device *dev = &host->pdev->dev;
575 u32 value;
576 int ret;
577
578 ret = readl_poll_timeout(host->ioaddr + SDCMD, value,
579 !(value & SDCMD_NEW_FLAG), 1, 10);
580 if (ret == -ETIMEDOUT)
581 /* if it takes a while make poll interval bigger */
582 ret = readl_poll_timeout(host->ioaddr + SDCMD, value,
583 !(value & SDCMD_NEW_FLAG),
584 10, max_ms * 1000);
585 if (ret == -ETIMEDOUT)
586 dev_err(dev, "%s: timeout (%d ms)\n", __func__, max_ms);
587
588 return value;
589 }
590
bcm2835_finish_request(struct bcm2835_host * host)591 static void bcm2835_finish_request(struct bcm2835_host *host)
592 {
593 struct dma_chan *terminate_chan = NULL;
594 struct mmc_request *mrq;
595
596 cancel_delayed_work(&host->timeout_work);
597
598 mrq = host->mrq;
599
600 host->mrq = NULL;
601 host->cmd = NULL;
602 host->data = NULL;
603
604 host->dma_desc = NULL;
605 terminate_chan = host->dma_chan;
606 host->dma_chan = NULL;
607
608 if (terminate_chan) {
609 int err = dmaengine_terminate_all(terminate_chan);
610
611 if (err)
612 dev_err(&host->pdev->dev,
613 "failed to terminate DMA (%d)\n", err);
614 }
615
616 mmc_request_done(mmc_from_priv(host), mrq);
617 }
618
619 static
bcm2835_send_command(struct bcm2835_host * host,struct mmc_command * cmd)620 bool bcm2835_send_command(struct bcm2835_host *host, struct mmc_command *cmd)
621 {
622 struct device *dev = &host->pdev->dev;
623 u32 sdcmd, sdhsts;
624 unsigned long timeout;
625
626 WARN_ON(host->cmd);
627
628 sdcmd = bcm2835_read_wait_sdcmd(host, 100);
629 if (sdcmd & SDCMD_NEW_FLAG) {
630 dev_err(dev, "previous command never completed.\n");
631 bcm2835_dumpregs(host);
632 cmd->error = -EILSEQ;
633 bcm2835_finish_request(host);
634 return false;
635 }
636
637 if (!cmd->data && cmd->busy_timeout > 9000)
638 timeout = DIV_ROUND_UP(cmd->busy_timeout, 1000) * HZ + HZ;
639 else
640 timeout = 10 * HZ;
641 schedule_delayed_work(&host->timeout_work, timeout);
642
643 host->cmd = cmd;
644
645 /* Clear any error flags */
646 sdhsts = readl(host->ioaddr + SDHSTS);
647 if (sdhsts & SDHSTS_ERROR_MASK)
648 writel(sdhsts, host->ioaddr + SDHSTS);
649
650 if ((cmd->flags & MMC_RSP_136) && (cmd->flags & MMC_RSP_BUSY)) {
651 dev_err(dev, "unsupported response type!\n");
652 cmd->error = -EINVAL;
653 bcm2835_finish_request(host);
654 return false;
655 }
656
657 bcm2835_prepare_data(host, cmd);
658
659 writel(cmd->arg, host->ioaddr + SDARG);
660
661 sdcmd = cmd->opcode & SDCMD_CMD_MASK;
662
663 host->use_busy = false;
664 if (!(cmd->flags & MMC_RSP_PRESENT)) {
665 sdcmd |= SDCMD_NO_RESPONSE;
666 } else {
667 if (cmd->flags & MMC_RSP_136)
668 sdcmd |= SDCMD_LONG_RESPONSE;
669 if (cmd->flags & MMC_RSP_BUSY) {
670 sdcmd |= SDCMD_BUSYWAIT;
671 host->use_busy = true;
672 }
673 }
674
675 if (cmd->data) {
676 if (cmd->data->flags & MMC_DATA_WRITE)
677 sdcmd |= SDCMD_WRITE_CMD;
678 if (cmd->data->flags & MMC_DATA_READ)
679 sdcmd |= SDCMD_READ_CMD;
680 }
681
682 writel(sdcmd | SDCMD_NEW_FLAG, host->ioaddr + SDCMD);
683
684 return true;
685 }
686
bcm2835_transfer_complete(struct bcm2835_host * host)687 static void bcm2835_transfer_complete(struct bcm2835_host *host)
688 {
689 struct mmc_data *data;
690
691 WARN_ON(!host->data_complete);
692
693 data = host->data;
694 host->data = NULL;
695
696 /* Need to send CMD12 if -
697 * a) open-ended multiblock transfer (no CMD23)
698 * b) error in multiblock transfer
699 */
700 if (host->mrq->stop && (data->error || !host->use_sbc)) {
701 if (bcm2835_send_command(host, host->mrq->stop)) {
702 /* No busy, so poll for completion */
703 if (!host->use_busy)
704 bcm2835_finish_command(host);
705 }
706 } else {
707 bcm2835_wait_transfer_complete(host);
708 bcm2835_finish_request(host);
709 }
710 }
711
bcm2835_finish_data(struct bcm2835_host * host)712 static void bcm2835_finish_data(struct bcm2835_host *host)
713 {
714 struct device *dev = &host->pdev->dev;
715 struct mmc_data *data;
716
717 data = host->data;
718
719 host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN);
720 writel(host->hcfg, host->ioaddr + SDHCFG);
721
722 data->bytes_xfered = data->error ? 0 : (data->blksz * data->blocks);
723
724 host->data_complete = true;
725
726 if (host->cmd) {
727 /* Data managed to finish before the
728 * command completed. Make sure we do
729 * things in the proper order.
730 */
731 dev_dbg(dev, "Finished early - HSTS %08x\n",
732 readl(host->ioaddr + SDHSTS));
733 } else {
734 bcm2835_transfer_complete(host);
735 }
736 }
737
bcm2835_finish_command(struct bcm2835_host * host)738 static void bcm2835_finish_command(struct bcm2835_host *host)
739 {
740 struct device *dev = &host->pdev->dev;
741 struct mmc_command *cmd = host->cmd;
742 u32 sdcmd;
743
744 sdcmd = bcm2835_read_wait_sdcmd(host, 100);
745
746 /* Check for errors */
747 if (sdcmd & SDCMD_NEW_FLAG) {
748 dev_err(dev, "command never completed.\n");
749 bcm2835_dumpregs(host);
750 host->cmd->error = -EIO;
751 bcm2835_finish_request(host);
752 return;
753 } else if (sdcmd & SDCMD_FAIL_FLAG) {
754 u32 sdhsts = readl(host->ioaddr + SDHSTS);
755
756 /* Clear the errors */
757 writel(SDHSTS_ERROR_MASK, host->ioaddr + SDHSTS);
758
759 if (!(sdhsts & SDHSTS_CRC7_ERROR) ||
760 (host->cmd->opcode != MMC_SEND_OP_COND)) {
761 u32 edm, fsm;
762
763 if (sdhsts & SDHSTS_CMD_TIME_OUT) {
764 host->cmd->error = -ETIMEDOUT;
765 } else {
766 dev_err(dev, "unexpected command %d error\n",
767 host->cmd->opcode);
768 bcm2835_dumpregs(host);
769 host->cmd->error = -EILSEQ;
770 }
771 edm = readl(host->ioaddr + SDEDM);
772 fsm = edm & SDEDM_FSM_MASK;
773 if (fsm == SDEDM_FSM_READWAIT ||
774 fsm == SDEDM_FSM_WRITESTART1)
775 /* Kick the FSM out of its wait */
776 writel(edm | SDEDM_FORCE_DATA_MODE,
777 host->ioaddr + SDEDM);
778 bcm2835_finish_request(host);
779 return;
780 }
781 }
782
783 if (cmd->flags & MMC_RSP_PRESENT) {
784 if (cmd->flags & MMC_RSP_136) {
785 int i;
786
787 for (i = 0; i < 4; i++) {
788 cmd->resp[3 - i] =
789 readl(host->ioaddr + SDRSP0 + i * 4);
790 }
791 } else {
792 cmd->resp[0] = readl(host->ioaddr + SDRSP0);
793 }
794 }
795
796 if (cmd == host->mrq->sbc) {
797 /* Finished CMD23, now send actual command. */
798 host->cmd = NULL;
799 if (bcm2835_send_command(host, host->mrq->cmd)) {
800 if (host->data && host->dma_desc)
801 /* DMA transfer starts now, PIO starts
802 * after irq
803 */
804 bcm2835_start_dma(host);
805
806 if (!host->use_busy)
807 bcm2835_finish_command(host);
808 }
809 } else if (cmd == host->mrq->stop) {
810 /* Finished CMD12 */
811 bcm2835_finish_request(host);
812 } else {
813 /* Processed actual command. */
814 host->cmd = NULL;
815 if (!host->data)
816 bcm2835_finish_request(host);
817 else if (host->data_complete)
818 bcm2835_transfer_complete(host);
819 }
820 }
821
bcm2835_timeout(struct work_struct * work)822 static void bcm2835_timeout(struct work_struct *work)
823 {
824 struct delayed_work *d = to_delayed_work(work);
825 struct bcm2835_host *host =
826 container_of(d, struct bcm2835_host, timeout_work);
827 struct device *dev = &host->pdev->dev;
828
829 mutex_lock(&host->mutex);
830
831 if (host->mrq) {
832 dev_err(dev, "timeout waiting for hardware interrupt.\n");
833 bcm2835_dumpregs(host);
834
835 bcm2835_reset(mmc_from_priv(host));
836
837 if (host->data) {
838 host->data->error = -ETIMEDOUT;
839 bcm2835_finish_data(host);
840 } else {
841 if (host->cmd)
842 host->cmd->error = -ETIMEDOUT;
843 else
844 host->mrq->cmd->error = -ETIMEDOUT;
845
846 bcm2835_finish_request(host);
847 }
848 }
849
850 mutex_unlock(&host->mutex);
851 }
852
bcm2835_check_cmd_error(struct bcm2835_host * host,u32 intmask)853 static bool bcm2835_check_cmd_error(struct bcm2835_host *host, u32 intmask)
854 {
855 struct device *dev = &host->pdev->dev;
856
857 if (!(intmask & SDHSTS_ERROR_MASK))
858 return false;
859
860 if (!host->cmd)
861 return true;
862
863 dev_err(dev, "sdhost_busy_irq: intmask %08x\n", intmask);
864 if (intmask & SDHSTS_CRC7_ERROR) {
865 host->cmd->error = -EILSEQ;
866 } else if (intmask & (SDHSTS_CRC16_ERROR |
867 SDHSTS_FIFO_ERROR)) {
868 if (host->mrq->data)
869 host->mrq->data->error = -EILSEQ;
870 else
871 host->cmd->error = -EILSEQ;
872 } else if (intmask & SDHSTS_REW_TIME_OUT) {
873 if (host->mrq->data)
874 host->mrq->data->error = -ETIMEDOUT;
875 else
876 host->cmd->error = -ETIMEDOUT;
877 } else if (intmask & SDHSTS_CMD_TIME_OUT) {
878 host->cmd->error = -ETIMEDOUT;
879 }
880 bcm2835_dumpregs(host);
881 return true;
882 }
883
bcm2835_check_data_error(struct bcm2835_host * host,u32 intmask)884 static void bcm2835_check_data_error(struct bcm2835_host *host, u32 intmask)
885 {
886 if (!host->data)
887 return;
888 if (intmask & (SDHSTS_CRC16_ERROR | SDHSTS_FIFO_ERROR))
889 host->data->error = -EILSEQ;
890 if (intmask & SDHSTS_REW_TIME_OUT)
891 host->data->error = -ETIMEDOUT;
892 }
893
bcm2835_busy_irq(struct bcm2835_host * host)894 static void bcm2835_busy_irq(struct bcm2835_host *host)
895 {
896 if (WARN_ON(!host->cmd)) {
897 bcm2835_dumpregs(host);
898 return;
899 }
900
901 if (WARN_ON(!host->use_busy)) {
902 bcm2835_dumpregs(host);
903 return;
904 }
905 host->use_busy = false;
906
907 bcm2835_finish_command(host);
908 }
909
bcm2835_data_irq(struct bcm2835_host * host,u32 intmask)910 static void bcm2835_data_irq(struct bcm2835_host *host, u32 intmask)
911 {
912 /* There are no dedicated data/space available interrupt
913 * status bits, so it is necessary to use the single shared
914 * data/space available FIFO status bits. It is therefore not
915 * an error to get here when there is no data transfer in
916 * progress.
917 */
918 if (!host->data)
919 return;
920
921 bcm2835_check_data_error(host, intmask);
922 if (host->data->error)
923 goto finished;
924
925 if (host->data->flags & MMC_DATA_WRITE) {
926 /* Use the block interrupt for writes after the first block */
927 host->hcfg &= ~(SDHCFG_DATA_IRPT_EN);
928 host->hcfg |= SDHCFG_BLOCK_IRPT_EN;
929 writel(host->hcfg, host->ioaddr + SDHCFG);
930 bcm2835_transfer_pio(host);
931 } else {
932 bcm2835_transfer_pio(host);
933 host->blocks--;
934 if ((host->blocks == 0) || host->data->error)
935 goto finished;
936 }
937 return;
938
939 finished:
940 host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN);
941 writel(host->hcfg, host->ioaddr + SDHCFG);
942 }
943
bcm2835_data_threaded_irq(struct bcm2835_host * host)944 static void bcm2835_data_threaded_irq(struct bcm2835_host *host)
945 {
946 if (!host->data)
947 return;
948 if ((host->blocks == 0) || host->data->error)
949 bcm2835_finish_data(host);
950 }
951
bcm2835_block_irq(struct bcm2835_host * host)952 static void bcm2835_block_irq(struct bcm2835_host *host)
953 {
954 if (WARN_ON(!host->data)) {
955 bcm2835_dumpregs(host);
956 return;
957 }
958
959 if (!host->dma_desc) {
960 WARN_ON(!host->blocks);
961 if (host->data->error || (--host->blocks == 0))
962 bcm2835_finish_data(host);
963 else
964 bcm2835_transfer_pio(host);
965 } else if (host->data->flags & MMC_DATA_WRITE) {
966 bcm2835_finish_data(host);
967 }
968 }
969
bcm2835_irq(int irq,void * dev_id)970 static irqreturn_t bcm2835_irq(int irq, void *dev_id)
971 {
972 irqreturn_t result = IRQ_NONE;
973 struct bcm2835_host *host = dev_id;
974 u32 intmask;
975
976 spin_lock(&host->lock);
977
978 intmask = readl(host->ioaddr + SDHSTS);
979
980 writel(SDHSTS_BUSY_IRPT |
981 SDHSTS_BLOCK_IRPT |
982 SDHSTS_SDIO_IRPT |
983 SDHSTS_DATA_FLAG,
984 host->ioaddr + SDHSTS);
985
986 if (intmask & SDHSTS_BLOCK_IRPT) {
987 bcm2835_check_data_error(host, intmask);
988 host->irq_block = true;
989 result = IRQ_WAKE_THREAD;
990 }
991
992 if (intmask & SDHSTS_BUSY_IRPT) {
993 if (!bcm2835_check_cmd_error(host, intmask)) {
994 host->irq_busy = true;
995 result = IRQ_WAKE_THREAD;
996 } else {
997 result = IRQ_HANDLED;
998 }
999 }
1000
1001 /* There is no true data interrupt status bit, so it is
1002 * necessary to qualify the data flag with the interrupt
1003 * enable bit.
1004 */
1005 if ((intmask & SDHSTS_DATA_FLAG) &&
1006 (host->hcfg & SDHCFG_DATA_IRPT_EN)) {
1007 bcm2835_data_irq(host, intmask);
1008 host->irq_data = true;
1009 result = IRQ_WAKE_THREAD;
1010 }
1011
1012 spin_unlock(&host->lock);
1013
1014 return result;
1015 }
1016
bcm2835_threaded_irq(int irq,void * dev_id)1017 static irqreturn_t bcm2835_threaded_irq(int irq, void *dev_id)
1018 {
1019 struct bcm2835_host *host = dev_id;
1020 unsigned long flags;
1021 bool block, busy, data;
1022
1023 spin_lock_irqsave(&host->lock, flags);
1024
1025 block = host->irq_block;
1026 busy = host->irq_busy;
1027 data = host->irq_data;
1028 host->irq_block = false;
1029 host->irq_busy = false;
1030 host->irq_data = false;
1031
1032 spin_unlock_irqrestore(&host->lock, flags);
1033
1034 mutex_lock(&host->mutex);
1035
1036 if (block)
1037 bcm2835_block_irq(host);
1038 if (busy)
1039 bcm2835_busy_irq(host);
1040 if (data)
1041 bcm2835_data_threaded_irq(host);
1042
1043 mutex_unlock(&host->mutex);
1044
1045 return IRQ_HANDLED;
1046 }
1047
bcm2835_dma_complete_work(struct work_struct * work)1048 static void bcm2835_dma_complete_work(struct work_struct *work)
1049 {
1050 struct bcm2835_host *host =
1051 container_of(work, struct bcm2835_host, dma_work);
1052 struct mmc_data *data;
1053
1054 mutex_lock(&host->mutex);
1055
1056 data = host->data;
1057
1058 if (host->dma_chan) {
1059 dma_unmap_sg(host->dma_chan->device->dev,
1060 data->sg, data->sg_len,
1061 host->dma_dir);
1062
1063 host->dma_chan = NULL;
1064 }
1065
1066 if (host->drain_words) {
1067 void *page;
1068 u32 *buf;
1069
1070 if (host->drain_offset & PAGE_MASK) {
1071 host->drain_page += host->drain_offset >> PAGE_SHIFT;
1072 host->drain_offset &= ~PAGE_MASK;
1073 }
1074 page = kmap_local_page(host->drain_page);
1075 buf = page + host->drain_offset;
1076
1077 while (host->drain_words) {
1078 u32 edm = readl(host->ioaddr + SDEDM);
1079
1080 if ((edm >> 4) & 0x1f)
1081 *(buf++) = readl(host->ioaddr + SDDATA);
1082 host->drain_words--;
1083 }
1084
1085 kunmap_local(page);
1086 }
1087
1088 bcm2835_finish_data(host);
1089
1090 mutex_unlock(&host->mutex);
1091 }
1092
bcm2835_set_clock(struct bcm2835_host * host,unsigned int clock)1093 static void bcm2835_set_clock(struct bcm2835_host *host, unsigned int clock)
1094 {
1095 struct mmc_host *mmc = mmc_from_priv(host);
1096 int div;
1097
1098 /* The SDCDIV register has 11 bits, and holds (div - 2). But
1099 * in data mode the max is 50MHz wihout a minimum, and only
1100 * the bottom 3 bits are used. Since the switch over is
1101 * automatic (unless we have marked the card as slow...),
1102 * chosen values have to make sense in both modes. Ident mode
1103 * must be 100-400KHz, so can range check the requested
1104 * clock. CMD15 must be used to return to data mode, so this
1105 * can be monitored.
1106 *
1107 * clock 250MHz -> 0->125MHz, 1->83.3MHz, 2->62.5MHz, 3->50.0MHz
1108 * 4->41.7MHz, 5->35.7MHz, 6->31.3MHz, 7->27.8MHz
1109 *
1110 * 623->400KHz/27.8MHz
1111 * reset value (507)->491159/50MHz
1112 *
1113 * BUT, the 3-bit clock divisor in data mode is too small if
1114 * the core clock is higher than 250MHz, so instead use the
1115 * SLOW_CARD configuration bit to force the use of the ident
1116 * clock divisor at all times.
1117 */
1118
1119 if (clock < 100000) {
1120 /* Can't stop the clock, but make it as slow as possible
1121 * to show willing
1122 */
1123 host->cdiv = SDCDIV_MAX_CDIV;
1124 writel(host->cdiv, host->ioaddr + SDCDIV);
1125 return;
1126 }
1127
1128 div = host->max_clk / clock;
1129 if (div < 2)
1130 div = 2;
1131 if ((host->max_clk / div) > clock)
1132 div++;
1133 div -= 2;
1134
1135 if (div > SDCDIV_MAX_CDIV)
1136 div = SDCDIV_MAX_CDIV;
1137
1138 clock = host->max_clk / (div + 2);
1139 mmc->actual_clock = clock;
1140
1141 /* Calibrate some delays */
1142
1143 host->ns_per_fifo_word = (1000000000 / clock) *
1144 ((mmc->caps & MMC_CAP_4_BIT_DATA) ? 8 : 32);
1145
1146 host->cdiv = div;
1147 writel(host->cdiv, host->ioaddr + SDCDIV);
1148
1149 /* Set the timeout to 500ms */
1150 writel(mmc->actual_clock / 2, host->ioaddr + SDTOUT);
1151 }
1152
bcm2835_request(struct mmc_host * mmc,struct mmc_request * mrq)1153 static void bcm2835_request(struct mmc_host *mmc, struct mmc_request *mrq)
1154 {
1155 struct bcm2835_host *host = mmc_priv(mmc);
1156 struct device *dev = &host->pdev->dev;
1157 u32 edm, fsm;
1158
1159 /* Reset the error statuses in case this is a retry */
1160 if (mrq->sbc)
1161 mrq->sbc->error = 0;
1162 if (mrq->cmd)
1163 mrq->cmd->error = 0;
1164 if (mrq->data)
1165 mrq->data->error = 0;
1166 if (mrq->stop)
1167 mrq->stop->error = 0;
1168
1169 if (mrq->data && !is_power_of_2(mrq->data->blksz)) {
1170 dev_err(dev, "unsupported block size (%d bytes)\n",
1171 mrq->data->blksz);
1172
1173 if (mrq->cmd)
1174 mrq->cmd->error = -EINVAL;
1175
1176 mmc_request_done(mmc, mrq);
1177 return;
1178 }
1179
1180 mutex_lock(&host->mutex);
1181
1182 WARN_ON(host->mrq);
1183 host->mrq = mrq;
1184
1185 edm = readl(host->ioaddr + SDEDM);
1186 fsm = edm & SDEDM_FSM_MASK;
1187
1188 if ((fsm != SDEDM_FSM_IDENTMODE) &&
1189 (fsm != SDEDM_FSM_DATAMODE)) {
1190 dev_err(dev, "previous command (%d) not complete (EDM %08x)\n",
1191 readl(host->ioaddr + SDCMD) & SDCMD_CMD_MASK,
1192 edm);
1193 bcm2835_dumpregs(host);
1194
1195 if (mrq->cmd)
1196 mrq->cmd->error = -EILSEQ;
1197
1198 bcm2835_finish_request(host);
1199 mutex_unlock(&host->mutex);
1200 return;
1201 }
1202
1203 if (host->use_dma && mrq->data && (mrq->data->blocks > PIO_THRESHOLD))
1204 bcm2835_prepare_dma(host, mrq->data);
1205
1206 host->use_sbc = !!mrq->sbc && host->mrq->data &&
1207 (host->mrq->data->flags & MMC_DATA_READ);
1208 if (host->use_sbc) {
1209 if (bcm2835_send_command(host, mrq->sbc)) {
1210 if (!host->use_busy)
1211 bcm2835_finish_command(host);
1212 }
1213 } else if (mrq->cmd && bcm2835_send_command(host, mrq->cmd)) {
1214 if (host->data && host->dma_desc) {
1215 /* DMA transfer starts now, PIO starts after irq */
1216 bcm2835_start_dma(host);
1217 }
1218
1219 if (!host->use_busy)
1220 bcm2835_finish_command(host);
1221 }
1222
1223 mutex_unlock(&host->mutex);
1224 }
1225
bcm2835_set_ios(struct mmc_host * mmc,struct mmc_ios * ios)1226 static void bcm2835_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1227 {
1228 struct bcm2835_host *host = mmc_priv(mmc);
1229
1230 mutex_lock(&host->mutex);
1231
1232 if (!ios->clock || ios->clock != host->clock) {
1233 bcm2835_set_clock(host, ios->clock);
1234 host->clock = ios->clock;
1235 }
1236
1237 /* set bus width */
1238 host->hcfg &= ~SDHCFG_WIDE_EXT_BUS;
1239 if (ios->bus_width == MMC_BUS_WIDTH_4)
1240 host->hcfg |= SDHCFG_WIDE_EXT_BUS;
1241
1242 host->hcfg |= SDHCFG_WIDE_INT_BUS;
1243
1244 /* Disable clever clock switching, to cope with fast core clocks */
1245 host->hcfg |= SDHCFG_SLOW_CARD;
1246
1247 writel(host->hcfg, host->ioaddr + SDHCFG);
1248
1249 mutex_unlock(&host->mutex);
1250 }
1251
1252 static const struct mmc_host_ops bcm2835_ops = {
1253 .request = bcm2835_request,
1254 .set_ios = bcm2835_set_ios,
1255 .card_hw_reset = bcm2835_reset,
1256 };
1257
bcm2835_add_host(struct bcm2835_host * host)1258 static int bcm2835_add_host(struct bcm2835_host *host)
1259 {
1260 struct mmc_host *mmc = mmc_from_priv(host);
1261 struct device *dev = &host->pdev->dev;
1262 char pio_limit_string[20];
1263 int ret;
1264
1265 if (!mmc->f_max || mmc->f_max > host->max_clk)
1266 mmc->f_max = host->max_clk;
1267 mmc->f_min = host->max_clk / SDCDIV_MAX_CDIV;
1268
1269 mmc->max_busy_timeout = ~0 / (mmc->f_max / 1000);
1270
1271 dev_dbg(dev, "f_max %d, f_min %d, max_busy_timeout %d\n",
1272 mmc->f_max, mmc->f_min, mmc->max_busy_timeout);
1273
1274 /* host controller capabilities */
1275 mmc->caps |= MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
1276 MMC_CAP_NEEDS_POLL | MMC_CAP_HW_RESET | MMC_CAP_CMD23;
1277
1278 spin_lock_init(&host->lock);
1279 mutex_init(&host->mutex);
1280
1281 if (!host->dma_chan_rxtx) {
1282 dev_warn(dev, "unable to initialise DMA channel. Falling back to PIO\n");
1283 host->use_dma = false;
1284 } else {
1285 host->use_dma = true;
1286
1287 host->dma_cfg_tx.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1288 host->dma_cfg_tx.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1289 host->dma_cfg_tx.direction = DMA_MEM_TO_DEV;
1290 host->dma_cfg_tx.src_addr = 0;
1291 host->dma_cfg_tx.dst_addr = host->phys_addr + SDDATA;
1292
1293 host->dma_cfg_rx.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1294 host->dma_cfg_rx.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1295 host->dma_cfg_rx.direction = DMA_DEV_TO_MEM;
1296 host->dma_cfg_rx.src_addr = host->phys_addr + SDDATA;
1297 host->dma_cfg_rx.dst_addr = 0;
1298
1299 if (dmaengine_slave_config(host->dma_chan_rxtx,
1300 &host->dma_cfg_tx) != 0 ||
1301 dmaengine_slave_config(host->dma_chan_rxtx,
1302 &host->dma_cfg_rx) != 0)
1303 host->use_dma = false;
1304 }
1305
1306 mmc->max_segs = 128;
1307 mmc->max_req_size = min_t(size_t, 524288, dma_max_mapping_size(dev));
1308 mmc->max_seg_size = mmc->max_req_size;
1309 mmc->max_blk_size = 1024;
1310 mmc->max_blk_count = 65535;
1311
1312 /* report supported voltage ranges */
1313 mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1314
1315 INIT_WORK(&host->dma_work, bcm2835_dma_complete_work);
1316 INIT_DELAYED_WORK(&host->timeout_work, bcm2835_timeout);
1317
1318 /* Set interrupt enables */
1319 host->hcfg = SDHCFG_BUSY_IRPT_EN;
1320
1321 bcm2835_reset_internal(host);
1322
1323 ret = request_threaded_irq(host->irq, bcm2835_irq,
1324 bcm2835_threaded_irq,
1325 0, mmc_hostname(mmc), host);
1326 if (ret) {
1327 dev_err(dev, "failed to request IRQ %d: %d\n", host->irq, ret);
1328 return ret;
1329 }
1330
1331 ret = mmc_add_host(mmc);
1332 if (ret) {
1333 free_irq(host->irq, host);
1334 return ret;
1335 }
1336
1337 pio_limit_string[0] = '\0';
1338 if (host->use_dma && (PIO_THRESHOLD > 0))
1339 sprintf(pio_limit_string, " (>%d)", PIO_THRESHOLD);
1340 dev_info(dev, "loaded - DMA %s%s\n",
1341 host->use_dma ? "enabled" : "disabled", pio_limit_string);
1342
1343 return 0;
1344 }
1345
bcm2835_suspend(struct device * dev)1346 static int bcm2835_suspend(struct device *dev)
1347 {
1348 struct bcm2835_host *host = dev_get_drvdata(dev);
1349
1350 clk_disable_unprepare(host->clk);
1351
1352 return 0;
1353 }
1354
bcm2835_resume(struct device * dev)1355 static int bcm2835_resume(struct device *dev)
1356 {
1357 struct bcm2835_host *host = dev_get_drvdata(dev);
1358
1359 return clk_prepare_enable(host->clk);
1360 }
1361
1362 static DEFINE_SIMPLE_DEV_PM_OPS(bcm2835_pm_ops, bcm2835_suspend,
1363 bcm2835_resume);
1364
bcm2835_probe(struct platform_device * pdev)1365 static int bcm2835_probe(struct platform_device *pdev)
1366 {
1367 struct device *dev = &pdev->dev;
1368 struct bcm2835_host *host;
1369 struct mmc_host *mmc;
1370 const __be32 *regaddr_p;
1371 int ret;
1372
1373 dev_dbg(dev, "%s\n", __func__);
1374 mmc = mmc_alloc_host(sizeof(*host), dev);
1375 if (!mmc)
1376 return -ENOMEM;
1377
1378 mmc->ops = &bcm2835_ops;
1379 host = mmc_priv(mmc);
1380 host->pdev = pdev;
1381 spin_lock_init(&host->lock);
1382
1383 host->ioaddr = devm_platform_ioremap_resource(pdev, 0);
1384 if (IS_ERR(host->ioaddr)) {
1385 ret = PTR_ERR(host->ioaddr);
1386 goto err;
1387 }
1388
1389 /* Parse OF address directly to get the physical address for
1390 * DMA to our registers.
1391 */
1392 regaddr_p = of_get_address(pdev->dev.of_node, 0, NULL, NULL);
1393 if (!regaddr_p) {
1394 dev_err(dev, "Can't get phys address\n");
1395 ret = -EINVAL;
1396 goto err;
1397 }
1398
1399 host->phys_addr = be32_to_cpup(regaddr_p);
1400
1401 host->dma_chan = NULL;
1402 host->dma_desc = NULL;
1403
1404 host->dma_chan_rxtx = dma_request_chan(dev, "rx-tx");
1405 if (IS_ERR(host->dma_chan_rxtx)) {
1406 ret = PTR_ERR(host->dma_chan_rxtx);
1407 host->dma_chan_rxtx = NULL;
1408
1409 if (ret == -EPROBE_DEFER)
1410 goto err;
1411
1412 /* Ignore errors to fall back to PIO mode */
1413 }
1414
1415 host->irq = platform_get_irq(pdev, 0);
1416 if (host->irq < 0) {
1417 ret = host->irq;
1418 goto err;
1419 }
1420
1421 ret = mmc_of_parse(mmc);
1422 if (ret)
1423 goto err;
1424
1425 host->clk = devm_clk_get(dev, NULL);
1426 if (IS_ERR(host->clk)) {
1427 ret = dev_err_probe(dev, PTR_ERR(host->clk), "could not get clk\n");
1428 goto err;
1429 }
1430
1431 ret = clk_prepare_enable(host->clk);
1432 if (ret)
1433 goto err;
1434
1435 host->max_clk = clk_get_rate(host->clk);
1436
1437 ret = bcm2835_add_host(host);
1438 if (ret)
1439 goto err_clk;
1440
1441 platform_set_drvdata(pdev, host);
1442
1443 dev_dbg(dev, "%s -> OK\n", __func__);
1444
1445 return 0;
1446
1447 err_clk:
1448 clk_disable_unprepare(host->clk);
1449 err:
1450 dev_dbg(dev, "%s -> err %d\n", __func__, ret);
1451 if (host->dma_chan_rxtx)
1452 dma_release_channel(host->dma_chan_rxtx);
1453 mmc_free_host(mmc);
1454
1455 return ret;
1456 }
1457
bcm2835_remove(struct platform_device * pdev)1458 static void bcm2835_remove(struct platform_device *pdev)
1459 {
1460 struct bcm2835_host *host = platform_get_drvdata(pdev);
1461 struct mmc_host *mmc = mmc_from_priv(host);
1462
1463 mmc_remove_host(mmc);
1464
1465 writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD);
1466
1467 free_irq(host->irq, host);
1468
1469 cancel_work_sync(&host->dma_work);
1470 cancel_delayed_work_sync(&host->timeout_work);
1471
1472 clk_disable_unprepare(host->clk);
1473
1474 if (host->dma_chan_rxtx)
1475 dma_release_channel(host->dma_chan_rxtx);
1476
1477 mmc_free_host(mmc);
1478 }
1479
1480 static const struct of_device_id bcm2835_match[] = {
1481 { .compatible = "brcm,bcm2835-sdhost" },
1482 { }
1483 };
1484 MODULE_DEVICE_TABLE(of, bcm2835_match);
1485
1486 static struct platform_driver bcm2835_driver = {
1487 .probe = bcm2835_probe,
1488 .remove = bcm2835_remove,
1489 .driver = {
1490 .name = "sdhost-bcm2835",
1491 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1492 .of_match_table = bcm2835_match,
1493 .pm = pm_ptr(&bcm2835_pm_ops),
1494 },
1495 };
1496 module_platform_driver(bcm2835_driver);
1497
1498 MODULE_ALIAS("platform:sdhost-bcm2835");
1499 MODULE_DESCRIPTION("BCM2835 SDHost driver");
1500 MODULE_LICENSE("GPL v2");
1501 MODULE_AUTHOR("Phil Elwell");
1502