xref: /openbmc/u-boot/drivers/mmc/pxa_mmc_gen.c (revision e8f80a5a)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2010 Marek Vasut <marek.vasut@gmail.com>
4  *
5  * Loosely based on the old code and Linux's PXA MMC driver
6  */
7 
8 #include <common.h>
9 #include <asm/arch/hardware.h>
10 #include <asm/arch/regs-mmc.h>
11 #include <linux/errno.h>
12 #include <asm/io.h>
13 #include <malloc.h>
14 #include <mmc.h>
15 
16 /* PXAMMC Generic default config for various CPUs */
17 #if defined(CONFIG_CPU_PXA25X)
18 #define PXAMMC_FIFO_SIZE	1
19 #define PXAMMC_MIN_SPEED	312500
20 #define PXAMMC_MAX_SPEED	20000000
21 #define PXAMMC_HOST_CAPS	(0)
22 #elif defined(CONFIG_CPU_PXA27X)
23 #define PXAMMC_CRC_SKIP
24 #define PXAMMC_FIFO_SIZE	32
25 #define PXAMMC_MIN_SPEED	304000
26 #define PXAMMC_MAX_SPEED	19500000
27 #define PXAMMC_HOST_CAPS	(MMC_MODE_4BIT)
28 #elif defined(CONFIG_CPU_MONAHANS)
29 #define PXAMMC_FIFO_SIZE	32
30 #define PXAMMC_MIN_SPEED	304000
31 #define PXAMMC_MAX_SPEED	26000000
32 #define PXAMMC_HOST_CAPS	(MMC_MODE_4BIT | MMC_MODE_HS)
33 #else
34 #error "This CPU isn't supported by PXA MMC!"
35 #endif
36 
37 #define MMC_STAT_ERRORS							\
38 	(MMC_STAT_RES_CRC_ERROR | MMC_STAT_SPI_READ_ERROR_TOKEN |	\
39 	MMC_STAT_CRC_READ_ERROR | MMC_STAT_TIME_OUT_RESPONSE |		\
40 	MMC_STAT_READ_TIME_OUT | MMC_STAT_CRC_WRITE_ERROR)
41 
42 /* 1 millisecond (in wait cycles below it's 100 x 10uS waits) */
43 #define PXA_MMC_TIMEOUT	100
44 
45 struct pxa_mmc_priv {
46 	struct pxa_mmc_regs *regs;
47 };
48 
49 /* Wait for bit to be set */
pxa_mmc_wait(struct mmc * mmc,uint32_t mask)50 static int pxa_mmc_wait(struct mmc *mmc, uint32_t mask)
51 {
52 	struct pxa_mmc_priv *priv = mmc->priv;
53 	struct pxa_mmc_regs *regs = priv->regs;
54 	unsigned int timeout = PXA_MMC_TIMEOUT;
55 
56 	/* Wait for bit to be set */
57 	while (--timeout) {
58 		if (readl(&regs->stat) & mask)
59 			break;
60 		udelay(10);
61 	}
62 
63 	if (!timeout)
64 		return -ETIMEDOUT;
65 
66 	return 0;
67 }
68 
pxa_mmc_stop_clock(struct mmc * mmc)69 static int pxa_mmc_stop_clock(struct mmc *mmc)
70 {
71 	struct pxa_mmc_priv *priv = mmc->priv;
72 	struct pxa_mmc_regs *regs = priv->regs;
73 	unsigned int timeout = PXA_MMC_TIMEOUT;
74 
75 	/* If the clock aren't running, exit */
76 	if (!(readl(&regs->stat) & MMC_STAT_CLK_EN))
77 		return 0;
78 
79 	/* Tell the controller to turn off the clock */
80 	writel(MMC_STRPCL_STOP_CLK, &regs->strpcl);
81 
82 	/* Wait until the clock are off */
83 	while (--timeout) {
84 		if (!(readl(&regs->stat) & MMC_STAT_CLK_EN))
85 			break;
86 		udelay(10);
87 	}
88 
89 	/* The clock refused to stop, scream and die a painful death */
90 	if (!timeout)
91 		return -ETIMEDOUT;
92 
93 	/* The clock stopped correctly */
94 	return 0;
95 }
96 
pxa_mmc_start_cmd(struct mmc * mmc,struct mmc_cmd * cmd,uint32_t cmdat)97 static int pxa_mmc_start_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
98 				uint32_t cmdat)
99 {
100 	struct pxa_mmc_priv *priv = mmc->priv;
101 	struct pxa_mmc_regs *regs = priv->regs;
102 	int ret;
103 
104 	/* The card can send a "busy" response */
105 	if (cmd->resp_type & MMC_RSP_BUSY)
106 		cmdat |= MMC_CMDAT_BUSY;
107 
108 	/* Inform the controller about response type */
109 	switch (cmd->resp_type) {
110 	case MMC_RSP_R1:
111 	case MMC_RSP_R1b:
112 		cmdat |= MMC_CMDAT_R1;
113 		break;
114 	case MMC_RSP_R2:
115 		cmdat |= MMC_CMDAT_R2;
116 		break;
117 	case MMC_RSP_R3:
118 		cmdat |= MMC_CMDAT_R3;
119 		break;
120 	default:
121 		break;
122 	}
123 
124 	/* Load command and it's arguments into the controller */
125 	writel(cmd->cmdidx, &regs->cmd);
126 	writel(cmd->cmdarg >> 16, &regs->argh);
127 	writel(cmd->cmdarg & 0xffff, &regs->argl);
128 	writel(cmdat, &regs->cmdat);
129 
130 	/* Start the controller clock and wait until they are started */
131 	writel(MMC_STRPCL_START_CLK, &regs->strpcl);
132 
133 	ret = pxa_mmc_wait(mmc, MMC_STAT_CLK_EN);
134 	if (ret)
135 		return ret;
136 
137 	/* Correct and happy end */
138 	return 0;
139 }
140 
pxa_mmc_cmd_done(struct mmc * mmc,struct mmc_cmd * cmd)141 static int pxa_mmc_cmd_done(struct mmc *mmc, struct mmc_cmd *cmd)
142 {
143 	struct pxa_mmc_priv *priv = mmc->priv;
144 	struct pxa_mmc_regs *regs = priv->regs;
145 	uint32_t a, b, c;
146 	int i;
147 	int stat;
148 
149 	/* Read the controller status */
150 	stat = readl(&regs->stat);
151 
152 	/*
153 	 * Linux says:
154 	 * Did I mention this is Sick.  We always need to
155 	 * discard the upper 8 bits of the first 16-bit word.
156 	 */
157 	a = readl(&regs->res) & 0xffff;
158 	for (i = 0; i < 4; i++) {
159 		b = readl(&regs->res) & 0xffff;
160 		c = readl(&regs->res) & 0xffff;
161 		cmd->response[i] = (a << 24) | (b << 8) | (c >> 8);
162 		a = c;
163 	}
164 
165 	/* The command response didn't arrive */
166 	if (stat & MMC_STAT_TIME_OUT_RESPONSE)
167 		return -ETIMEDOUT;
168 	else if (stat & MMC_STAT_RES_CRC_ERROR
169 			&& cmd->resp_type & MMC_RSP_CRC) {
170 #ifdef	PXAMMC_CRC_SKIP
171 		if (cmd->resp_type & MMC_RSP_136
172 				&& cmd->response[0] & (1 << 31))
173 			printf("Ignoring CRC, this may be dangerous!\n");
174 		else
175 #endif
176 		return -EILSEQ;
177 	}
178 
179 	/* The command response was successfully read */
180 	return 0;
181 }
182 
pxa_mmc_do_read_xfer(struct mmc * mmc,struct mmc_data * data)183 static int pxa_mmc_do_read_xfer(struct mmc *mmc, struct mmc_data *data)
184 {
185 	struct pxa_mmc_priv *priv = mmc->priv;
186 	struct pxa_mmc_regs *regs = priv->regs;
187 	uint32_t len;
188 	uint32_t *buf = (uint32_t *)data->dest;
189 	int size;
190 	int ret;
191 
192 	len = data->blocks * data->blocksize;
193 
194 	while (len) {
195 		/* The controller has data ready */
196 		if (readl(&regs->i_reg) & MMC_I_REG_RXFIFO_RD_REQ) {
197 			size = min(len, (uint32_t)PXAMMC_FIFO_SIZE);
198 			len -= size;
199 			size /= 4;
200 
201 			/* Read data into the buffer */
202 			while (size--)
203 				*buf++ = readl(&regs->rxfifo);
204 
205 		}
206 
207 		if (readl(&regs->stat) & MMC_STAT_ERRORS)
208 			return -EIO;
209 	}
210 
211 	/* Wait for the transmission-done interrupt */
212 	ret = pxa_mmc_wait(mmc, MMC_STAT_DATA_TRAN_DONE);
213 	if (ret)
214 		return ret;
215 
216 	return 0;
217 }
218 
pxa_mmc_do_write_xfer(struct mmc * mmc,struct mmc_data * data)219 static int pxa_mmc_do_write_xfer(struct mmc *mmc, struct mmc_data *data)
220 {
221 	struct pxa_mmc_priv *priv = mmc->priv;
222 	struct pxa_mmc_regs *regs = priv->regs;
223 	uint32_t len;
224 	uint32_t *buf = (uint32_t *)data->src;
225 	int size;
226 	int ret;
227 
228 	len = data->blocks * data->blocksize;
229 
230 	while (len) {
231 		/* The controller is ready to receive data */
232 		if (readl(&regs->i_reg) & MMC_I_REG_TXFIFO_WR_REQ) {
233 			size = min(len, (uint32_t)PXAMMC_FIFO_SIZE);
234 			len -= size;
235 			size /= 4;
236 
237 			while (size--)
238 				writel(*buf++, &regs->txfifo);
239 
240 			if (min(len, (uint32_t)PXAMMC_FIFO_SIZE) < 32)
241 				writel(MMC_PRTBUF_BUF_PART_FULL, &regs->prtbuf);
242 		}
243 
244 		if (readl(&regs->stat) & MMC_STAT_ERRORS)
245 			return -EIO;
246 	}
247 
248 	/* Wait for the transmission-done interrupt */
249 	ret = pxa_mmc_wait(mmc, MMC_STAT_DATA_TRAN_DONE);
250 	if (ret)
251 		return ret;
252 
253 	/* Wait until the data are really written to the card */
254 	ret = pxa_mmc_wait(mmc, MMC_STAT_PRG_DONE);
255 	if (ret)
256 		return ret;
257 
258 	return 0;
259 }
260 
pxa_mmc_request(struct mmc * mmc,struct mmc_cmd * cmd,struct mmc_data * data)261 static int pxa_mmc_request(struct mmc *mmc, struct mmc_cmd *cmd,
262 				struct mmc_data *data)
263 {
264 	struct pxa_mmc_priv *priv = mmc->priv;
265 	struct pxa_mmc_regs *regs = priv->regs;
266 	uint32_t cmdat = 0;
267 	int ret;
268 
269 	/* Stop the controller */
270 	ret = pxa_mmc_stop_clock(mmc);
271 	if (ret)
272 		return ret;
273 
274 	/* If we're doing data transfer, configure the controller accordingly */
275 	if (data) {
276 		writel(data->blocks, &regs->nob);
277 		writel(data->blocksize, &regs->blklen);
278 		/* This delay can be optimized, but stick with max value */
279 		writel(0xffff, &regs->rdto);
280 		cmdat |= MMC_CMDAT_DATA_EN;
281 		if (data->flags & MMC_DATA_WRITE)
282 			cmdat |= MMC_CMDAT_WRITE;
283 	}
284 
285 	/* Run in 4bit mode if the card can do it */
286 	if (mmc->bus_width == 4)
287 		cmdat |= MMC_CMDAT_SD_4DAT;
288 
289 	/* Execute the command */
290 	ret = pxa_mmc_start_cmd(mmc, cmd, cmdat);
291 	if (ret)
292 		return ret;
293 
294 	/* Wait until the command completes */
295 	ret = pxa_mmc_wait(mmc, MMC_STAT_END_CMD_RES);
296 	if (ret)
297 		return ret;
298 
299 	/* Read back the result */
300 	ret = pxa_mmc_cmd_done(mmc, cmd);
301 	if (ret)
302 		return ret;
303 
304 	/* In case there was a data transfer scheduled, do it */
305 	if (data) {
306 		if (data->flags & MMC_DATA_WRITE)
307 			pxa_mmc_do_write_xfer(mmc, data);
308 		else
309 			pxa_mmc_do_read_xfer(mmc, data);
310 	}
311 
312 	return 0;
313 }
314 
pxa_mmc_set_ios(struct mmc * mmc)315 static int pxa_mmc_set_ios(struct mmc *mmc)
316 {
317 	struct pxa_mmc_priv *priv = mmc->priv;
318 	struct pxa_mmc_regs *regs = priv->regs;
319 	uint32_t tmp;
320 	uint32_t pxa_mmc_clock;
321 
322 	if (!mmc->clock) {
323 		pxa_mmc_stop_clock(mmc);
324 		return 0;
325 	}
326 
327 	/* PXA3xx can do 26MHz with special settings. */
328 	if (mmc->clock == 26000000) {
329 		writel(0x7, &regs->clkrt);
330 		return 0;
331 	}
332 
333 	/* Set clock to the card the usual way. */
334 	pxa_mmc_clock = 0;
335 	tmp = mmc->cfg->f_max / mmc->clock;
336 	tmp += tmp % 2;
337 
338 	while (tmp > 1) {
339 		pxa_mmc_clock++;
340 		tmp >>= 1;
341 	}
342 
343 	writel(pxa_mmc_clock, &regs->clkrt);
344 
345 	return 0;
346 }
347 
pxa_mmc_init(struct mmc * mmc)348 static int pxa_mmc_init(struct mmc *mmc)
349 {
350 	struct pxa_mmc_priv *priv = mmc->priv;
351 	struct pxa_mmc_regs *regs = priv->regs;
352 
353 	/* Make sure the clock are stopped */
354 	pxa_mmc_stop_clock(mmc);
355 
356 	/* Turn off SPI mode */
357 	writel(0, &regs->spi);
358 
359 	/* Set up maximum timeout to wait for command response */
360 	writel(MMC_RES_TO_MAX_MASK, &regs->resto);
361 
362 	/* Mask all interrupts */
363 	writel(~(MMC_I_MASK_TXFIFO_WR_REQ | MMC_I_MASK_RXFIFO_RD_REQ),
364 		&regs->i_mask);
365 	return 0;
366 }
367 
368 static const struct mmc_ops pxa_mmc_ops = {
369 	.send_cmd	= pxa_mmc_request,
370 	.set_ios	= pxa_mmc_set_ios,
371 	.init		= pxa_mmc_init,
372 };
373 
374 static struct mmc_config pxa_mmc_cfg = {
375 	.name		= "PXA MMC",
376 	.ops		= &pxa_mmc_ops,
377 	.voltages	= MMC_VDD_32_33 | MMC_VDD_33_34,
378 	.f_max		= PXAMMC_MAX_SPEED,
379 	.f_min		= PXAMMC_MIN_SPEED,
380 	.host_caps	= PXAMMC_HOST_CAPS,
381 	.b_max		= CONFIG_SYS_MMC_MAX_BLK_COUNT,
382 };
383 
pxa_mmc_register(int card_index)384 int pxa_mmc_register(int card_index)
385 {
386 	struct mmc *mmc;
387 	struct pxa_mmc_priv *priv;
388 	uint32_t reg;
389 	int ret = -ENOMEM;
390 
391 	priv = malloc(sizeof(struct pxa_mmc_priv));
392 	if (!priv)
393 		goto err0;
394 
395 	memset(priv, 0, sizeof(*priv));
396 
397 	switch (card_index) {
398 	case 0:
399 		priv->regs = (struct pxa_mmc_regs *)MMC0_BASE;
400 		break;
401 	case 1:
402 		priv->regs = (struct pxa_mmc_regs *)MMC1_BASE;
403 		break;
404 	default:
405 		ret = -EINVAL;
406 		printf("PXA MMC: Invalid MMC controller ID (card_index = %d)\n",
407 			card_index);
408 		goto err1;
409 	}
410 
411 #ifndef	CONFIG_CPU_MONAHANS	/* PXA2xx */
412 	reg = readl(CKEN);
413 	reg |= CKEN12_MMC;
414 	writel(reg, CKEN);
415 #else				/* PXA3xx */
416 	reg = readl(CKENA);
417 	reg |= CKENA_12_MMC0 | CKENA_13_MMC1;
418 	writel(reg, CKENA);
419 #endif
420 
421 	mmc = mmc_create(&pxa_mmc_cfg, priv);
422 	if (mmc == NULL)
423 		goto err1;
424 
425 	return 0;
426 
427 err1:
428 	free(priv);
429 err0:
430 	return ret;
431 }
432