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  * This code was ported to U-Boot by
21  *  Alexander Graf <agraf@suse.de>
22  * and is based on drivers/mmc/host/bcm2835.c in Linux which is written by
23  *  Phil Elwell <phil@raspberrypi.org>
24  *  Copyright (C) 2015-2016 Raspberry Pi (Trading) Ltd.
25  * which is based on
26  *  mmc-bcm2835.c by Gellert Weisz
27  * which is, in turn, based on
28  *  sdhci-bcm2708.c by Broadcom
29  *  sdhci-bcm2835.c by Stephen Warren and Oleksandr Tymoshenko
30  *  sdhci.c and sdhci-pci.c by Pierre Ossman
31  */
32 #include <clk.h>
33 #include <common.h>
34 #include <dm.h>
35 #include <mmc.h>
36 #include <asm/arch/msg.h>
37 #include <asm/arch/mbox.h>
38 #include <asm/unaligned.h>
39 #include <dm/device_compat.h>
40 #include <linux/bitops.h>
41 #include <linux/bug.h>
42 #include <linux/compat.h>
43 #include <linux/delay.h>
44 #include <linux/io.h>
45 #include <linux/iopoll.h>
46 #include <linux/sizes.h>
47 #include <mach/gpio.h>
48 #include <power/regulator.h>
49 
50 #define msleep(a) udelay(a * 1000)
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 #define SDHSTS_DATA_FLAG		0x01
88 
89 #define SDHSTS_CLEAR_MASK		(SDHSTS_BUSY_IRPT | \
90 					 SDHSTS_BLOCK_IRPT | \
91 					 SDHSTS_SDIO_IRPT | \
92 					 SDHSTS_REW_TIME_OUT | \
93 					 SDHSTS_CMD_TIME_OUT | \
94 					 SDHSTS_CRC16_ERROR | \
95 					 SDHSTS_CRC7_ERROR | \
96 					 SDHSTS_FIFO_ERROR)
97 
98 #define SDHSTS_TRANSFER_ERROR_MASK	(SDHSTS_CRC7_ERROR | \
99 					 SDHSTS_CRC16_ERROR | \
100 					 SDHSTS_REW_TIME_OUT | \
101 					 SDHSTS_FIFO_ERROR)
102 
103 #define SDHSTS_ERROR_MASK		(SDHSTS_CMD_TIME_OUT | \
104 					 SDHSTS_TRANSFER_ERROR_MASK)
105 
106 #define SDHCFG_BUSY_IRPT_EN	BIT(10)
107 #define SDHCFG_BLOCK_IRPT_EN	BIT(8)
108 #define SDHCFG_SDIO_IRPT_EN	BIT(5)
109 #define SDHCFG_DATA_IRPT_EN	BIT(4)
110 #define SDHCFG_SLOW_CARD	BIT(3)
111 #define SDHCFG_WIDE_EXT_BUS	BIT(2)
112 #define SDHCFG_WIDE_INT_BUS	BIT(1)
113 #define SDHCFG_REL_CMD_LINE	BIT(0)
114 
115 #define SDVDD_POWER_OFF		0
116 #define SDVDD_POWER_ON		1
117 
118 #define SDEDM_FORCE_DATA_MODE	BIT(19)
119 #define SDEDM_CLOCK_PULSE	BIT(20)
120 #define SDEDM_BYPASS		BIT(21)
121 
122 #define SDEDM_FIFO_FILL_SHIFT	4
123 #define SDEDM_FIFO_FILL_MASK	0x1f
edm_fifo_fill(u32 edm)124 static u32 edm_fifo_fill(u32 edm)
125 {
126 	return (edm >> SDEDM_FIFO_FILL_SHIFT) & SDEDM_FIFO_FILL_MASK;
127 }
128 
129 #define SDEDM_WRITE_THRESHOLD_SHIFT	9
130 #define SDEDM_READ_THRESHOLD_SHIFT	14
131 #define SDEDM_THRESHOLD_MASK		0x1f
132 
133 #define SDEDM_FSM_MASK		0xf
134 #define SDEDM_FSM_IDENTMODE	0x0
135 #define SDEDM_FSM_DATAMODE	0x1
136 #define SDEDM_FSM_READDATA	0x2
137 #define SDEDM_FSM_WRITEDATA	0x3
138 #define SDEDM_FSM_READWAIT	0x4
139 #define SDEDM_FSM_READCRC	0x5
140 #define SDEDM_FSM_WRITECRC	0x6
141 #define SDEDM_FSM_WRITEWAIT1	0x7
142 #define SDEDM_FSM_POWERDOWN	0x8
143 #define SDEDM_FSM_POWERUP	0x9
144 #define SDEDM_FSM_WRITESTART1	0xa
145 #define SDEDM_FSM_WRITESTART2	0xb
146 #define SDEDM_FSM_GENPULSES	0xc
147 #define SDEDM_FSM_WRITEWAIT2	0xd
148 #define SDEDM_FSM_STARTPOWDOWN	0xf
149 
150 #define SDDATA_FIFO_WORDS	16
151 
152 #define FIFO_READ_THRESHOLD	4
153 #define FIFO_WRITE_THRESHOLD	4
154 #define SDDATA_FIFO_PIO_BURST	8
155 
156 #define SDHST_TIMEOUT_MAX_USEC	100000
157 
158 struct bcm2835_plat {
159 	struct mmc_config cfg;
160 	struct mmc mmc;
161 };
162 
163 struct bcm2835_host {
164 	void __iomem		*ioaddr;
165 	u32			phys_addr;
166 
167 	int			clock;		/* Current clock speed */
168 	unsigned int		max_clk;	/* Max possible freq */
169 	unsigned int		blocks;		/* remaining PIO blocks */
170 
171 	u32			ns_per_fifo_word;
172 
173 	/* cached registers */
174 	u32			hcfg;
175 	u32			cdiv;
176 
177 	struct mmc_cmd	*cmd;		/* Current command */
178 	struct mmc_data		*data;		/* Current data request */
179 	bool			use_busy:1;	/* Wait for busy interrupt */
180 
181 	struct udevice		*dev;
182 	struct mmc		*mmc;
183 	struct bcm2835_plat	*plat;
184 };
185 
bcm2835_dumpregs(struct bcm2835_host * host)186 static void bcm2835_dumpregs(struct bcm2835_host *host)
187 {
188 	dev_dbg(host->dev, "=========== REGISTER DUMP ===========\n");
189 	dev_dbg(host->dev, "SDCMD  0x%08x\n", readl(host->ioaddr + SDCMD));
190 	dev_dbg(host->dev, "SDARG  0x%08x\n", readl(host->ioaddr + SDARG));
191 	dev_dbg(host->dev, "SDTOUT 0x%08x\n", readl(host->ioaddr + SDTOUT));
192 	dev_dbg(host->dev, "SDCDIV 0x%08x\n", readl(host->ioaddr + SDCDIV));
193 	dev_dbg(host->dev, "SDRSP0 0x%08x\n", readl(host->ioaddr + SDRSP0));
194 	dev_dbg(host->dev, "SDRSP1 0x%08x\n", readl(host->ioaddr + SDRSP1));
195 	dev_dbg(host->dev, "SDRSP2 0x%08x\n", readl(host->ioaddr + SDRSP2));
196 	dev_dbg(host->dev, "SDRSP3 0x%08x\n", readl(host->ioaddr + SDRSP3));
197 	dev_dbg(host->dev, "SDHSTS 0x%08x\n", readl(host->ioaddr + SDHSTS));
198 	dev_dbg(host->dev, "SDVDD  0x%08x\n", readl(host->ioaddr + SDVDD));
199 	dev_dbg(host->dev, "SDEDM  0x%08x\n", readl(host->ioaddr + SDEDM));
200 	dev_dbg(host->dev, "SDHCFG 0x%08x\n", readl(host->ioaddr + SDHCFG));
201 	dev_dbg(host->dev, "SDHBCT 0x%08x\n", readl(host->ioaddr + SDHBCT));
202 	dev_dbg(host->dev, "SDHBLC 0x%08x\n", readl(host->ioaddr + SDHBLC));
203 	dev_dbg(host->dev, "===========================================\n");
204 }
205 
bcm2835_reset_internal(struct bcm2835_host * host)206 static void bcm2835_reset_internal(struct bcm2835_host *host)
207 {
208 	u32 temp;
209 
210 	writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD);
211 	writel(0, host->ioaddr + SDCMD);
212 	writel(0, host->ioaddr + SDARG);
213 	/* Set timeout to a big enough value so we don't hit it */
214 	writel(0xf00000, host->ioaddr + SDTOUT);
215 	writel(0, host->ioaddr + SDCDIV);
216 	/* Clear status register */
217 	writel(SDHSTS_CLEAR_MASK, host->ioaddr + SDHSTS);
218 	writel(0, host->ioaddr + SDHCFG);
219 	writel(0, host->ioaddr + SDHBCT);
220 	writel(0, host->ioaddr + SDHBLC);
221 
222 	/* Limit fifo usage due to silicon bug */
223 	temp = readl(host->ioaddr + SDEDM);
224 	temp &= ~((SDEDM_THRESHOLD_MASK << SDEDM_READ_THRESHOLD_SHIFT) |
225 		  (SDEDM_THRESHOLD_MASK << SDEDM_WRITE_THRESHOLD_SHIFT));
226 	temp |= (FIFO_READ_THRESHOLD << SDEDM_READ_THRESHOLD_SHIFT) |
227 		(FIFO_WRITE_THRESHOLD << SDEDM_WRITE_THRESHOLD_SHIFT);
228 	writel(temp, host->ioaddr + SDEDM);
229 	/* Wait for FIFO threshold to populate */
230 	msleep(20);
231 	writel(SDVDD_POWER_ON, host->ioaddr + SDVDD);
232 	/* Wait for all components to go through power on cycle */
233 	msleep(20);
234 	host->clock = 0;
235 	writel(host->hcfg, host->ioaddr + SDHCFG);
236 	writel(host->cdiv, host->ioaddr + SDCDIV);
237 }
238 
bcm2835_wait_transfer_complete(struct bcm2835_host * host)239 static int bcm2835_wait_transfer_complete(struct bcm2835_host *host)
240 {
241 	ulong tstart_ms = get_timer(0);
242 
243 	while (1) {
244 		u32 edm, fsm;
245 
246 		edm = readl(host->ioaddr + SDEDM);
247 		fsm = edm & SDEDM_FSM_MASK;
248 
249 		if ((fsm == SDEDM_FSM_IDENTMODE) ||
250 		    (fsm == SDEDM_FSM_DATAMODE))
251 			break;
252 
253 		if ((fsm == SDEDM_FSM_READWAIT) ||
254 		    (fsm == SDEDM_FSM_WRITESTART1) ||
255 		    (fsm == SDEDM_FSM_READDATA)) {
256 			writel(edm | SDEDM_FORCE_DATA_MODE,
257 			       host->ioaddr + SDEDM);
258 			break;
259 		}
260 
261 		/* Error out after ~1s */
262 		ulong tlapse_ms = get_timer(tstart_ms);
263 		if ( tlapse_ms > 1000 /* ms */ ) {
264 
265 			dev_err(host->dev,
266 				"wait_transfer_complete - still waiting after %lu ms\n",
267 				tlapse_ms);
268 			bcm2835_dumpregs(host);
269 			return -ETIMEDOUT;
270 		}
271 	}
272 
273 	return 0;
274 }
275 
bcm2835_transfer_block_pio(struct bcm2835_host * host,bool is_read)276 static int bcm2835_transfer_block_pio(struct bcm2835_host *host, bool is_read)
277 {
278 	struct mmc_data *data = host->data;
279 	size_t blksize = data->blocksize;
280 	int copy_words;
281 	u32 hsts = 0;
282 	u32 *buf;
283 
284 	if (blksize % sizeof(u32))
285 		return -EINVAL;
286 
287 	buf = is_read ? (u32 *)data->dest : (u32 *)data->src;
288 
289 	if (is_read)
290 		data->dest += blksize;
291 	else
292 		data->src += blksize;
293 
294 	copy_words = blksize / sizeof(u32);
295 
296 	/*
297 	 * Copy all contents from/to the FIFO as far as it reaches,
298 	 * then wait for it to fill/empty again and rewind.
299 	 */
300 	while (copy_words) {
301 		int burst_words, words;
302 		u32 edm;
303 
304 		burst_words = min(SDDATA_FIFO_PIO_BURST, copy_words);
305 		edm = readl(host->ioaddr + SDEDM);
306 		if (is_read)
307 			words = edm_fifo_fill(edm);
308 		else
309 			words = SDDATA_FIFO_WORDS - edm_fifo_fill(edm);
310 
311 		if (words < burst_words) {
312 			int fsm_state = (edm & SDEDM_FSM_MASK);
313 
314 			if ((is_read &&
315 			     (fsm_state != SDEDM_FSM_READDATA &&
316 			      fsm_state != SDEDM_FSM_READWAIT &&
317 			      fsm_state != SDEDM_FSM_READCRC)) ||
318 			    (!is_read &&
319 			     (fsm_state != SDEDM_FSM_WRITEDATA &&
320 			      fsm_state != SDEDM_FSM_WRITEWAIT1 &&
321 			      fsm_state != SDEDM_FSM_WRITEWAIT2 &&
322 			      fsm_state != SDEDM_FSM_WRITECRC &&
323 			      fsm_state != SDEDM_FSM_WRITESTART1 &&
324 			      fsm_state != SDEDM_FSM_WRITESTART2))) {
325 				hsts = readl(host->ioaddr + SDHSTS);
326 				printf("fsm %x, hsts %08x\n", fsm_state, hsts);
327 				if (hsts & SDHSTS_ERROR_MASK)
328 					break;
329 			}
330 
331 			continue;
332 		} else if (words > copy_words) {
333 			words = copy_words;
334 		}
335 
336 		copy_words -= words;
337 
338 		/* Copy current chunk to/from the FIFO */
339 		while (words) {
340 			if (is_read)
341 				*(buf++) = readl(host->ioaddr + SDDATA);
342 			else
343 				writel(*(buf++), host->ioaddr + SDDATA);
344 			words--;
345 		}
346 	}
347 
348 	return 0;
349 }
350 
bcm2835_transfer_pio(struct bcm2835_host * host)351 static int bcm2835_transfer_pio(struct bcm2835_host *host)
352 {
353 	u32 sdhsts;
354 	bool is_read;
355 	int ret = 0;
356 
357 	is_read = (host->data->flags & MMC_DATA_READ) != 0;
358 	ret = bcm2835_transfer_block_pio(host, is_read);
359 	if (ret)
360 		return ret;
361 
362 	sdhsts = readl(host->ioaddr + SDHSTS);
363 	if (sdhsts & (SDHSTS_CRC16_ERROR |
364 		      SDHSTS_CRC7_ERROR |
365 		      SDHSTS_FIFO_ERROR)) {
366 		printf("%s transfer error - HSTS %08x\n",
367 		       is_read ? "read" : "write", sdhsts);
368 		ret =  -EILSEQ;
369 	} else if ((sdhsts & (SDHSTS_CMD_TIME_OUT |
370 			      SDHSTS_REW_TIME_OUT))) {
371 		printf("%s timeout error - HSTS %08x\n",
372 		       is_read ? "read" : "write", sdhsts);
373 		ret = -ETIMEDOUT;
374 	}
375 
376 	return ret;
377 }
378 
bcm2835_prepare_data(struct bcm2835_host * host,struct mmc_cmd * cmd,struct mmc_data * data)379 static void bcm2835_prepare_data(struct bcm2835_host *host, struct mmc_cmd *cmd,
380 				 struct mmc_data *data)
381 {
382 	WARN_ON(host->data);
383 
384 	host->data = data;
385 	if (!data)
386 		return;
387 
388 	/* Use PIO */
389 	host->blocks = data->blocks;
390 
391 	writel(data->blocksize, host->ioaddr + SDHBCT);
392 	writel(data->blocks, host->ioaddr + SDHBLC);
393 }
394 
bcm2835_read_wait_sdcmd(struct bcm2835_host * host)395 static u32 bcm2835_read_wait_sdcmd(struct bcm2835_host *host)
396 {
397 	u32 value;
398 	int ret;
399 	int timeout_us = SDHST_TIMEOUT_MAX_USEC;
400 
401 	ret = readl_poll_timeout(host->ioaddr + SDCMD, value,
402 				 !(value & SDCMD_NEW_FLAG), timeout_us);
403 	if (ret == -ETIMEDOUT)
404 		printf("%s: timeout (%d us)\n", __func__, timeout_us);
405 
406 	return value;
407 }
408 
bcm2835_send_command(struct bcm2835_host * host,struct mmc_cmd * cmd,struct mmc_data * data)409 static int bcm2835_send_command(struct bcm2835_host *host, struct mmc_cmd *cmd,
410 				struct mmc_data *data)
411 {
412 	u32 sdcmd, sdhsts;
413 
414 	WARN_ON(host->cmd);
415 
416 	if ((cmd->resp_type & MMC_RSP_136) && (cmd->resp_type & MMC_RSP_BUSY)) {
417 		printf("unsupported response type!\n");
418 		return -EINVAL;
419 	}
420 
421 	sdcmd = bcm2835_read_wait_sdcmd(host);
422 	if (sdcmd & SDCMD_NEW_FLAG) {
423 		printf("previous command never completed.\n");
424 		bcm2835_dumpregs(host);
425 		return -EBUSY;
426 	}
427 
428 	host->cmd = cmd;
429 
430 	/* Clear any error flags */
431 	sdhsts = readl(host->ioaddr + SDHSTS);
432 	if (sdhsts & SDHSTS_ERROR_MASK)
433 		writel(sdhsts, host->ioaddr + SDHSTS);
434 
435 	bcm2835_prepare_data(host, cmd, data);
436 
437 	writel(cmd->cmdarg, host->ioaddr + SDARG);
438 
439 	sdcmd = cmd->cmdidx & SDCMD_CMD_MASK;
440 
441 	host->use_busy = false;
442 	if (!(cmd->resp_type & MMC_RSP_PRESENT)) {
443 		sdcmd |= SDCMD_NO_RESPONSE;
444 	} else {
445 		if (cmd->resp_type & MMC_RSP_136)
446 			sdcmd |= SDCMD_LONG_RESPONSE;
447 		if (cmd->resp_type & MMC_RSP_BUSY) {
448 			sdcmd |= SDCMD_BUSYWAIT;
449 			host->use_busy = true;
450 		}
451 	}
452 
453 	if (data) {
454 		if (data->flags & MMC_DATA_WRITE)
455 			sdcmd |= SDCMD_WRITE_CMD;
456 		if (data->flags & MMC_DATA_READ)
457 			sdcmd |= SDCMD_READ_CMD;
458 	}
459 
460 	writel(sdcmd | SDCMD_NEW_FLAG, host->ioaddr + SDCMD);
461 
462 	return 0;
463 }
464 
bcm2835_finish_command(struct bcm2835_host * host)465 static int bcm2835_finish_command(struct bcm2835_host *host)
466 {
467 	struct mmc_cmd *cmd = host->cmd;
468 	u32 sdcmd;
469 	int ret = 0;
470 
471 	sdcmd = bcm2835_read_wait_sdcmd(host);
472 
473 	/* Check for errors */
474 	if (sdcmd & SDCMD_NEW_FLAG) {
475 		printf("command never completed.\n");
476 		bcm2835_dumpregs(host);
477 		return -EIO;
478 	} else if (sdcmd & SDCMD_FAIL_FLAG) {
479 		u32 sdhsts = readl(host->ioaddr + SDHSTS);
480 
481 		/* Clear the errors */
482 		writel(SDHSTS_ERROR_MASK, host->ioaddr + SDHSTS);
483 
484 		if (!(sdhsts & SDHSTS_CRC7_ERROR) ||
485 		    (host->cmd->cmdidx != MMC_CMD_SEND_OP_COND)) {
486 			if (sdhsts & SDHSTS_CMD_TIME_OUT) {
487 				ret = -ETIMEDOUT;
488 			} else {
489 				printf("unexpected command %d error\n",
490 				       host->cmd->cmdidx);
491 				bcm2835_dumpregs(host);
492 				ret = -EILSEQ;
493 			}
494 
495 			return ret;
496 		}
497 	}
498 
499 	if (cmd->resp_type & MMC_RSP_PRESENT) {
500 		if (cmd->resp_type & MMC_RSP_136) {
501 			int i;
502 
503 			for (i = 0; i < 4; i++) {
504 				cmd->response[3 - i] =
505 					readl(host->ioaddr + SDRSP0 + i * 4);
506 			}
507 		} else {
508 			cmd->response[0] = readl(host->ioaddr + SDRSP0);
509 		}
510 	}
511 
512 	/* Processed actual command. */
513 	host->cmd = NULL;
514 
515 	return ret;
516 }
517 
bcm2835_check_cmd_error(struct bcm2835_host * host,u32 intmask)518 static int bcm2835_check_cmd_error(struct bcm2835_host *host, u32 intmask)
519 {
520 	int ret = -EINVAL;
521 
522 	if (!(intmask & SDHSTS_ERROR_MASK))
523 		return 0;
524 
525 	if (!host->cmd)
526 		return -EINVAL;
527 
528 	printf("sdhost_busy_irq: intmask %08x\n", intmask);
529 	if (intmask & SDHSTS_CRC7_ERROR) {
530 		ret = -EILSEQ;
531 	} else if (intmask & (SDHSTS_CRC16_ERROR |
532 			      SDHSTS_FIFO_ERROR)) {
533 		ret = -EILSEQ;
534 	} else if (intmask & (SDHSTS_REW_TIME_OUT | SDHSTS_CMD_TIME_OUT)) {
535 		ret = -ETIMEDOUT;
536 	}
537 	bcm2835_dumpregs(host);
538 	return ret;
539 }
540 
bcm2835_check_data_error(struct bcm2835_host * host,u32 intmask)541 static int bcm2835_check_data_error(struct bcm2835_host *host, u32 intmask)
542 {
543 	int ret = 0;
544 
545 	if (!host->data)
546 		return 0;
547 	if (intmask & (SDHSTS_CRC16_ERROR | SDHSTS_FIFO_ERROR))
548 		ret = -EILSEQ;
549 	if (intmask & SDHSTS_REW_TIME_OUT)
550 		ret = -ETIMEDOUT;
551 
552 	if (ret)
553 		printf("%s:%d %d\n", __func__, __LINE__, ret);
554 
555 	return ret;
556 }
557 
bcm2835_transmit(struct bcm2835_host * host)558 static int bcm2835_transmit(struct bcm2835_host *host)
559 {
560 	u32 intmask = readl(host->ioaddr + SDHSTS);
561 	int ret;
562 
563 	/* Check for errors */
564 	ret = bcm2835_check_data_error(host, intmask);
565 	if (ret)
566 		return ret;
567 
568 	ret = bcm2835_check_cmd_error(host, intmask);
569 	if (ret)
570 		return ret;
571 
572 	/* Handle wait for busy end */
573 	if (host->use_busy && (intmask & SDHSTS_BUSY_IRPT)) {
574 		writel(SDHSTS_BUSY_IRPT, host->ioaddr + SDHSTS);
575 		host->use_busy = false;
576 		bcm2835_finish_command(host);
577 	}
578 
579 	/* Handle PIO data transfer */
580 	if (host->data) {
581 		ret = bcm2835_transfer_pio(host);
582 		if (ret)
583 			return ret;
584 		host->blocks--;
585 		if (host->blocks == 0) {
586 			/* Wait for command to complete for real */
587 			ret = bcm2835_wait_transfer_complete(host);
588 			if (ret)
589 				return ret;
590 			/* Transfer complete */
591 			host->data = NULL;
592 		}
593 	}
594 
595 	return 0;
596 }
597 
bcm2835_set_clock(struct bcm2835_host * host,unsigned int clock)598 static void bcm2835_set_clock(struct bcm2835_host *host, unsigned int clock)
599 {
600 	int div;
601 
602 	/* The SDCDIV register has 11 bits, and holds (div - 2).  But
603 	 * in data mode the max is 50MHz wihout a minimum, and only
604 	 * the bottom 3 bits are used. Since the switch over is
605 	 * automatic (unless we have marked the card as slow...),
606 	 * chosen values have to make sense in both modes.  Ident mode
607 	 * must be 100-400KHz, so can range check the requested
608 	 * clock. CMD15 must be used to return to data mode, so this
609 	 * can be monitored.
610 	 *
611 	 * clock 250MHz -> 0->125MHz, 1->83.3MHz, 2->62.5MHz, 3->50.0MHz
612 	 *                 4->41.7MHz, 5->35.7MHz, 6->31.3MHz, 7->27.8MHz
613 	 *
614 	 *		 623->400KHz/27.8MHz
615 	 *		 reset value (507)->491159/50MHz
616 	 *
617 	 * BUT, the 3-bit clock divisor in data mode is too small if
618 	 * the core clock is higher than 250MHz, so instead use the
619 	 * SLOW_CARD configuration bit to force the use of the ident
620 	 * clock divisor at all times.
621 	 */
622 
623 	if (clock < 100000) {
624 		/* Can't stop the clock, but make it as slow as possible
625 		 * to show willing
626 		 */
627 		host->cdiv = SDCDIV_MAX_CDIV;
628 		writel(host->cdiv, host->ioaddr + SDCDIV);
629 		return;
630 	}
631 
632 	div = host->max_clk / clock;
633 	if (div < 2)
634 		div = 2;
635 	if ((host->max_clk / div) > clock)
636 		div++;
637 	div -= 2;
638 
639 	if (div > SDCDIV_MAX_CDIV)
640 		div = SDCDIV_MAX_CDIV;
641 
642 	clock = host->max_clk / (div + 2);
643 	host->mmc->clock = clock;
644 
645 	/* Calibrate some delays */
646 
647 	host->ns_per_fifo_word = (1000000000 / clock) *
648 		((host->mmc->card_caps & MMC_MODE_4BIT) ? 8 : 32);
649 
650 	host->cdiv = div;
651 	writel(host->cdiv, host->ioaddr + SDCDIV);
652 
653 	/* Set the timeout to 500ms */
654 	writel(host->mmc->clock / 2, host->ioaddr + SDTOUT);
655 }
656 
is_power_of_2(u64 x)657 static inline int is_power_of_2(u64 x)
658 {
659 	return !(x & (x - 1));
660 }
661 
bcm2835_send_cmd(struct udevice * dev,struct mmc_cmd * cmd,struct mmc_data * data)662 static int bcm2835_send_cmd(struct udevice *dev, struct mmc_cmd *cmd,
663 			    struct mmc_data *data)
664 {
665 	struct bcm2835_host *host = dev_get_priv(dev);
666 	u32 edm, fsm;
667 	int ret = 0;
668 
669 	if (data && !is_power_of_2(data->blocksize)) {
670 		printf("unsupported block size (%d bytes)\n", data->blocksize);
671 
672 		if (cmd)
673 			return -EINVAL;
674 	}
675 
676 	edm = readl(host->ioaddr + SDEDM);
677 	fsm = edm & SDEDM_FSM_MASK;
678 
679 	if ((fsm != SDEDM_FSM_IDENTMODE) &&
680 	    (fsm != SDEDM_FSM_DATAMODE) &&
681 	    (cmd && cmd->cmdidx != MMC_CMD_STOP_TRANSMISSION)) {
682 		printf("previous command (%d) not complete (EDM %08x)\n",
683 		       readl(host->ioaddr + SDCMD) & SDCMD_CMD_MASK, edm);
684 		bcm2835_dumpregs(host);
685 
686 		if (cmd)
687 			return -EILSEQ;
688 
689 		return 0;
690 	}
691 
692 	if (cmd) {
693 		ret = bcm2835_send_command(host, cmd, data);
694 		if (!ret && !host->use_busy)
695 			ret = bcm2835_finish_command(host);
696 	}
697 
698 	/* Wait for completion of busy signal or data transfer */
699 	while (host->use_busy || host->data) {
700 		ret = bcm2835_transmit(host);
701 		if (ret)
702 			break;
703 	}
704 
705 	return ret;
706 }
707 
bcm2835_set_ios(struct udevice * dev)708 static int bcm2835_set_ios(struct udevice *dev)
709 {
710 	struct bcm2835_host *host = dev_get_priv(dev);
711 	struct mmc *mmc = mmc_get_mmc_dev(dev);
712 
713 	if (!mmc->clock || mmc->clock != host->clock) {
714 		bcm2835_set_clock(host, mmc->clock);
715 		host->clock = mmc->clock;
716 	}
717 
718 	/* set bus width */
719 	host->hcfg &= ~SDHCFG_WIDE_EXT_BUS;
720 	if (mmc->bus_width == 4)
721 		host->hcfg |= SDHCFG_WIDE_EXT_BUS;
722 
723 	host->hcfg |= SDHCFG_WIDE_INT_BUS;
724 
725 	/* Disable clever clock switching, to cope with fast core clocks */
726 	host->hcfg |= SDHCFG_SLOW_CARD;
727 
728 	writel(host->hcfg, host->ioaddr + SDHCFG);
729 
730 	return 0;
731 }
732 
bcm2835_add_host(struct bcm2835_host * host)733 static void bcm2835_add_host(struct bcm2835_host *host)
734 {
735 	struct mmc_config *cfg = &host->plat->cfg;
736 
737 	cfg->f_max = host->max_clk;
738 	cfg->f_min = host->max_clk / SDCDIV_MAX_CDIV;
739 	cfg->b_max = 65535;
740 
741 	dev_dbg(host->dev, "f_max %d, f_min %d\n",
742 		cfg->f_max, cfg->f_min);
743 
744 	/* host controller capabilities */
745 	cfg->host_caps = MMC_MODE_4BIT | MMC_MODE_HS | MMC_MODE_HS_52MHz;
746 
747 	/* report supported voltage ranges */
748 	cfg->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
749 
750 	/* Set interrupt enables */
751 	host->hcfg = SDHCFG_BUSY_IRPT_EN;
752 
753 	bcm2835_reset_internal(host);
754 }
755 
bcm2835_probe(struct udevice * dev)756 static int bcm2835_probe(struct udevice *dev)
757 {
758 	struct bcm2835_plat *plat = dev_get_plat(dev);
759 	struct bcm2835_host *host = dev_get_priv(dev);
760 	struct mmc *mmc = mmc_get_mmc_dev(dev);
761 	struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
762 
763 	host->dev = dev;
764 	host->mmc = mmc;
765 	host->plat = plat;
766 	upriv->mmc = &plat->mmc;
767 	plat->cfg.name = dev->name;
768 
769 	host->phys_addr = dev_read_addr(dev);
770 	if (host->phys_addr == FDT_ADDR_T_NONE)
771 		return -EINVAL;
772 
773 	host->ioaddr = devm_ioremap(dev, host->phys_addr, SZ_256);
774 	if (!host->ioaddr)
775 		return -ENOMEM;
776 
777 	host->max_clk = bcm2835_get_mmc_clock(BCM2835_MBOX_CLOCK_ID_CORE);
778 
779 	bcm2835_add_host(host);
780 
781 	dev_dbg(dev, "%s -> OK\n", __func__);
782 
783 	return 0;
784 }
785 
786 static const struct udevice_id bcm2835_match[] = {
787 	{ .compatible = "brcm,bcm2835-sdhost" },
788 	{ }
789 };
790 
791 static const struct dm_mmc_ops bcm2835_ops = {
792 	.send_cmd = bcm2835_send_cmd,
793 	.set_ios = bcm2835_set_ios,
794 };
795 
bcm2835_bind(struct udevice * dev)796 static int bcm2835_bind(struct udevice *dev)
797 {
798 	struct bcm2835_plat *plat = dev_get_plat(dev);
799 
800 	return mmc_bind(dev, &plat->mmc, &plat->cfg);
801 }
802 
803 U_BOOT_DRIVER(bcm2835_sdhost) = {
804 	.name = "bcm2835-sdhost",
805 	.id = UCLASS_MMC,
806 	.of_match = bcm2835_match,
807 	.bind = bcm2835_bind,
808 	.probe = bcm2835_probe,
809 	.priv_auto	= sizeof(struct bcm2835_host),
810 	.plat_auto	= sizeof(struct bcm2835_plat),
811 	.ops = &bcm2835_ops,
812 };
813