xref: /openbmc/u-boot/drivers/mmc/gen_atmel_mci.c (revision 68e7999b)
1 /*
2  * Copyright (C) 2010
3  * Rob Emanuele <rob@emanuele.us>
4  * Reinhard Meyer, EMK Elektronik <reinhard.meyer@emk-elektronik.de>
5  *
6  * Original Driver:
7  * Copyright (C) 2004-2006 Atmel Corporation
8  *
9  * SPDX-License-Identifier:	GPL-2.0+
10  */
11 
12 #include <common.h>
13 #include <mmc.h>
14 #include <part.h>
15 #include <malloc.h>
16 #include <asm/io.h>
17 #include <linux/errno.h>
18 #include <asm/byteorder.h>
19 #include <asm/arch/clk.h>
20 #include <asm/arch/hardware.h>
21 #include "atmel_mci.h"
22 
23 #ifndef CONFIG_SYS_MMC_CLK_OD
24 # define CONFIG_SYS_MMC_CLK_OD	150000
25 #endif
26 
27 #define MMC_DEFAULT_BLKLEN	512
28 
29 #if defined(CONFIG_ATMEL_MCI_PORTB)
30 # define MCI_BUS 1
31 #else
32 # define MCI_BUS 0
33 #endif
34 
35 struct atmel_mci_priv {
36 	struct mmc_config	cfg;
37 	struct atmel_mci	*mci;
38 	unsigned int		initialized:1;
39 	unsigned int		curr_clk;
40 };
41 
42 /* Read Atmel MCI IP version */
43 static unsigned int atmel_mci_get_version(struct atmel_mci *mci)
44 {
45 	return readl(&mci->version) & 0x00000fff;
46 }
47 
48 /*
49  * Print command and status:
50  *
51  * - always when DEBUG is defined
52  * - on command errors
53  */
54 static void dump_cmd(u32 cmdr, u32 arg, u32 status, const char* msg)
55 {
56 	debug("gen_atmel_mci: CMDR %08x (%2u) ARGR %08x (SR: %08x) %s\n",
57 	      cmdr, cmdr & 0x3F, arg, status, msg);
58 }
59 
60 /* Setup for MCI Clock and Block Size */
61 static void mci_set_mode(struct mmc *mmc, u32 hz, u32 blklen)
62 {
63 	struct atmel_mci_priv *priv = mmc->priv;
64 	atmel_mci_t *mci = priv->mci;
65 	u32 bus_hz = get_mci_clk_rate();
66 	u32 clkdiv = 255;
67 	unsigned int version = atmel_mci_get_version(mci);
68 	u32 clkodd = 0;
69 	u32 mr;
70 
71 	debug("mci: bus_hz is %u, setting clock %u Hz, block size %u\n",
72 		bus_hz, hz, blklen);
73 	if (hz > 0) {
74 		if (version >= 0x500) {
75 			clkdiv = DIV_ROUND_UP(bus_hz, hz) - 2;
76 			if (clkdiv > 511)
77 				clkdiv = 511;
78 
79 			clkodd = clkdiv & 1;
80 			clkdiv >>= 1;
81 
82 			debug("mci: setting clock %u Hz, block size %u\n",
83 			      bus_hz / (clkdiv * 2 + clkodd + 2), blklen);
84 		} else {
85 			/* find clkdiv yielding a rate <= than requested */
86 			for (clkdiv = 0; clkdiv < 255; clkdiv++) {
87 				if ((bus_hz / (clkdiv + 1) / 2) <= hz)
88 					break;
89 			}
90 			debug("mci: setting clock %u Hz, block size %u\n",
91 			      (bus_hz / (clkdiv + 1)) / 2, blklen);
92 
93 		}
94 	}
95 	if (version >= 0x500)
96 		priv->curr_clk = bus_hz / (clkdiv * 2 + clkodd + 2);
97 	else
98 		priv->curr_clk = (bus_hz / (clkdiv + 1)) / 2;
99 	blklen &= 0xfffc;
100 
101 	mr = MMCI_BF(CLKDIV, clkdiv);
102 
103 	/* MCI IP version >= 0x200 has R/WPROOF */
104 	if (version >= 0x200)
105 		mr |= MMCI_BIT(RDPROOF) | MMCI_BIT(WRPROOF);
106 
107 	/*
108 	 * MCI IP version >= 0x500 use bit 16 as clkodd.
109 	 * MCI IP version < 0x500 use upper 16 bits for blklen.
110 	 */
111 	if (version >= 0x500)
112 		mr |= MMCI_BF(CLKODD, clkodd);
113 	else
114 		mr |= MMCI_BF(BLKLEN, blklen);
115 
116 	writel(mr, &mci->mr);
117 
118 	/* MCI IP version >= 0x200 has blkr */
119 	if (version >= 0x200)
120 		writel(MMCI_BF(BLKLEN, blklen), &mci->blkr);
121 
122 	if (mmc->card_caps & mmc->cfg->host_caps & MMC_MODE_HS)
123 		writel(MMCI_BIT(HSMODE), &mci->cfg);
124 
125 	priv->initialized = 1;
126 }
127 
128 /* Return the CMDR with flags for a given command and data packet */
129 static u32 mci_encode_cmd(
130 	struct mmc_cmd *cmd, struct mmc_data *data, u32* error_flags)
131 {
132 	u32 cmdr = 0;
133 
134 	/* Default Flags for Errors */
135 	*error_flags |= (MMCI_BIT(DTOE) | MMCI_BIT(RDIRE) | MMCI_BIT(RENDE) |
136 		MMCI_BIT(RINDE) | MMCI_BIT(RTOE));
137 
138 	/* Default Flags for the Command */
139 	cmdr |= MMCI_BIT(MAXLAT);
140 
141 	if (data) {
142 		cmdr |= MMCI_BF(TRCMD, 1);
143 		if (data->blocks > 1)
144 			cmdr |= MMCI_BF(TRTYP, 1);
145 		if (data->flags & MMC_DATA_READ)
146 			cmdr |= MMCI_BIT(TRDIR);
147 	}
148 
149 	if (cmd->resp_type & MMC_RSP_CRC)
150 		*error_flags |= MMCI_BIT(RCRCE);
151 	if (cmd->resp_type & MMC_RSP_136)
152 		cmdr |= MMCI_BF(RSPTYP, 2);
153 	else if (cmd->resp_type & MMC_RSP_BUSY)
154 		cmdr |= MMCI_BF(RSPTYP, 3);
155 	else if (cmd->resp_type & MMC_RSP_PRESENT)
156 		cmdr |= MMCI_BF(RSPTYP, 1);
157 
158 	return cmdr | MMCI_BF(CMDNB, cmd->cmdidx);
159 }
160 
161 /* Entered into function pointer in mci_send_cmd */
162 static u32 mci_data_read(atmel_mci_t *mci, u32* data, u32 error_flags)
163 {
164 	u32 status;
165 
166 	do {
167 		status = readl(&mci->sr);
168 		if (status & (error_flags | MMCI_BIT(OVRE)))
169 			goto io_fail;
170 	} while (!(status & MMCI_BIT(RXRDY)));
171 
172 	if (status & MMCI_BIT(RXRDY)) {
173 		*data = readl(&mci->rdr);
174 		status = 0;
175 	}
176 io_fail:
177 	return status;
178 }
179 
180 /* Entered into function pointer in mci_send_cmd */
181 static u32 mci_data_write(atmel_mci_t *mci, u32* data, u32 error_flags)
182 {
183 	u32 status;
184 
185 	do {
186 		status = readl(&mci->sr);
187 		if (status & (error_flags | MMCI_BIT(UNRE)))
188 			goto io_fail;
189 	} while (!(status & MMCI_BIT(TXRDY)));
190 
191 	if (status & MMCI_BIT(TXRDY)) {
192 		writel(*data, &mci->tdr);
193 		status = 0;
194 	}
195 io_fail:
196 	return status;
197 }
198 
199 /*
200  * Entered into mmc structure during driver init
201  *
202  * Sends a command out on the bus and deals with the block data.
203  * Takes the mmc pointer, a command pointer, and an optional data pointer.
204  */
205 static int
206 mci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data)
207 {
208 	struct atmel_mci_priv *priv = mmc->priv;
209 	atmel_mci_t *mci = priv->mci;
210 	u32 cmdr;
211 	u32 error_flags = 0;
212 	u32 status;
213 
214 	if (!priv->initialized) {
215 		puts ("MCI not initialized!\n");
216 		return -ECOMM;
217 	}
218 
219 	/* Figure out the transfer arguments */
220 	cmdr = mci_encode_cmd(cmd, data, &error_flags);
221 
222 	/* For multi blocks read/write, set the block register */
223 	if ((cmd->cmdidx == MMC_CMD_READ_MULTIPLE_BLOCK)
224 			|| (cmd->cmdidx == MMC_CMD_WRITE_MULTIPLE_BLOCK))
225 		writel(data->blocks | MMCI_BF(BLKLEN, mmc->read_bl_len),
226 			&mci->blkr);
227 
228 	/* Send the command */
229 	writel(cmd->cmdarg, &mci->argr);
230 	writel(cmdr, &mci->cmdr);
231 
232 #ifdef DEBUG
233 	dump_cmd(cmdr, cmd->cmdarg, 0, "DEBUG");
234 #endif
235 
236 	/* Wait for the command to complete */
237 	while (!((status = readl(&mci->sr)) & MMCI_BIT(CMDRDY)));
238 
239 	if ((status & error_flags) & MMCI_BIT(RTOE)) {
240 		dump_cmd(cmdr, cmd->cmdarg, status, "Command Time Out");
241 		return -ETIMEDOUT;
242 	} else if (status & error_flags) {
243 		dump_cmd(cmdr, cmd->cmdarg, status, "Command Failed");
244 		return -ECOMM;
245 	}
246 
247 	/* Copy the response to the response buffer */
248 	if (cmd->resp_type & MMC_RSP_136) {
249 		cmd->response[0] = readl(&mci->rspr);
250 		cmd->response[1] = readl(&mci->rspr1);
251 		cmd->response[2] = readl(&mci->rspr2);
252 		cmd->response[3] = readl(&mci->rspr3);
253 	} else
254 		cmd->response[0] = readl(&mci->rspr);
255 
256 	/* transfer all of the blocks */
257 	if (data) {
258 		u32 word_count, block_count;
259 		u32* ioptr;
260 		u32 sys_blocksize, dummy, i;
261 		u32 (*mci_data_op)
262 			(atmel_mci_t *mci, u32* data, u32 error_flags);
263 
264 		if (data->flags & MMC_DATA_READ) {
265 			mci_data_op = mci_data_read;
266 			sys_blocksize = mmc->read_bl_len;
267 			ioptr = (u32*)data->dest;
268 		} else {
269 			mci_data_op = mci_data_write;
270 			sys_blocksize = mmc->write_bl_len;
271 			ioptr = (u32*)data->src;
272 		}
273 
274 		status = 0;
275 		for (block_count = 0;
276 				block_count < data->blocks && !status;
277 				block_count++) {
278 			word_count = 0;
279 			do {
280 				status = mci_data_op(mci, ioptr, error_flags);
281 				word_count++;
282 				ioptr++;
283 			} while (!status && word_count < (data->blocksize/4));
284 #ifdef DEBUG
285 			if (data->flags & MMC_DATA_READ)
286 			{
287 				u32 cnt = word_count * 4;
288 				printf("Read Data:\n");
289 				print_buffer(0, data->dest + cnt * block_count,
290 					     1, cnt, 0);
291 			}
292 #endif
293 #ifdef DEBUG
294 			if (!status && word_count < (sys_blocksize / 4))
295 				printf("filling rest of block...\n");
296 #endif
297 			/* fill the rest of a full block */
298 			while (!status && word_count < (sys_blocksize / 4)) {
299 				status = mci_data_op(mci, &dummy,
300 					error_flags);
301 				word_count++;
302 			}
303 			if (status) {
304 				dump_cmd(cmdr, cmd->cmdarg, status,
305 					"Data Transfer Failed");
306 				return -ECOMM;
307 			}
308 		}
309 
310 		/* Wait for Transfer End */
311 		i = 0;
312 		do {
313 			status = readl(&mci->sr);
314 
315 			if (status & error_flags) {
316 				dump_cmd(cmdr, cmd->cmdarg, status,
317 					"DTIP Wait Failed");
318 				return -ECOMM;
319 			}
320 			i++;
321 		} while ((status & MMCI_BIT(DTIP)) && i < 10000);
322 		if (status & MMCI_BIT(DTIP)) {
323 			dump_cmd(cmdr, cmd->cmdarg, status,
324 				"XFER DTIP never unset, ignoring");
325 		}
326 	}
327 
328 	/*
329 	 * After the switch command, wait for 8 clocks before the next
330 	 * command
331 	 */
332 	if (cmd->cmdidx == MMC_CMD_SWITCH)
333 		udelay(8*1000000 / priv->curr_clk); /* 8 clk in us */
334 
335 	return 0;
336 }
337 
338 /* Entered into mmc structure during driver init */
339 static int mci_set_ios(struct mmc *mmc)
340 {
341 	struct atmel_mci_priv *priv = mmc->priv;
342 	atmel_mci_t *mci = priv->mci;
343 	int bus_width = mmc->bus_width;
344 	unsigned int version = atmel_mci_get_version(mci);
345 	int busw;
346 
347 	/* Set the clock speed */
348 	mci_set_mode(mmc, mmc->clock, MMC_DEFAULT_BLKLEN);
349 
350 	/*
351 	 * set the bus width and select slot for this interface
352 	 * there is no capability for multiple slots on the same interface yet
353 	 */
354 	if ((version & 0xf00) >= 0x300) {
355 		switch (bus_width) {
356 		case 8:
357 			busw = 3;
358 			break;
359 		case 4:
360 			busw = 2;
361 			break;
362 		default:
363 			busw = 0;
364 			break;
365 		}
366 
367 		writel(busw << 6 | MMCI_BF(SCDSEL, MCI_BUS), &mci->sdcr);
368 	} else {
369 		busw = (bus_width == 4) ? 1 : 0;
370 
371 		writel(busw << 7 | MMCI_BF(SCDSEL, MCI_BUS), &mci->sdcr);
372 	}
373 
374 	return 0;
375 }
376 
377 /* Entered into mmc structure during driver init */
378 static int mci_init(struct mmc *mmc)
379 {
380 	struct atmel_mci_priv *priv = mmc->priv;
381 	atmel_mci_t *mci = priv->mci;
382 
383 	/* Initialize controller */
384 	writel(MMCI_BIT(SWRST), &mci->cr);	/* soft reset */
385 	writel(MMCI_BIT(PWSDIS), &mci->cr);	/* disable power save */
386 	writel(MMCI_BIT(MCIEN), &mci->cr);	/* enable mci */
387 	writel(MMCI_BF(SCDSEL, MCI_BUS), &mci->sdcr);	/* select port */
388 
389 	/* This delay can be optimized, but stick with max value */
390 	writel(0x7f, &mci->dtor);
391 	/* Disable Interrupts */
392 	writel(~0UL, &mci->idr);
393 
394 	/* Set default clocks and blocklen */
395 	mci_set_mode(mmc, CONFIG_SYS_MMC_CLK_OD, MMC_DEFAULT_BLKLEN);
396 
397 	return 0;
398 }
399 
400 static const struct mmc_ops atmel_mci_ops = {
401 	.send_cmd	= mci_send_cmd,
402 	.set_ios	= mci_set_ios,
403 	.init		= mci_init,
404 };
405 
406 /*
407  * This is the only exported function
408  *
409  * Call it with the MCI register base address
410  */
411 int atmel_mci_init(void *regs)
412 {
413 	struct mmc *mmc;
414 	struct mmc_config *cfg;
415 	struct atmel_mci_priv *priv;
416 	unsigned int version;
417 
418 	priv = calloc(1, sizeof(*priv));
419 	if (!priv)
420 		return -ENOMEM;
421 
422 	cfg = &priv->cfg;
423 
424 	cfg->name = "mci";
425 	cfg->ops = &atmel_mci_ops;
426 
427 	priv->mci = (struct atmel_mci *)regs;
428 	priv->initialized = 0;
429 
430 	/* need to be able to pass these in on a board by board basis */
431 	cfg->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
432 	version = atmel_mci_get_version(priv->mci);
433 	if ((version & 0xf00) >= 0x300) {
434 		cfg->host_caps = MMC_MODE_8BIT;
435 		cfg->host_caps |= MMC_MODE_HS | MMC_MODE_HS_52MHz;
436 	}
437 
438 	cfg->host_caps |= MMC_MODE_4BIT;
439 
440 	/*
441 	 * min and max frequencies determined by
442 	 * max and min of clock divider
443 	 */
444 	cfg->f_min = get_mci_clk_rate() / (2*256);
445 	cfg->f_max = get_mci_clk_rate() / (2*1);
446 
447 	cfg->b_max = CONFIG_SYS_MMC_MAX_BLK_COUNT;
448 
449 	mmc = mmc_create(cfg, priv);
450 
451 	if (mmc == NULL) {
452 		free(priv);
453 		return -ENODEV;
454 	}
455 	/* NOTE: possibly leaking the priv structure */
456 
457 	return 0;
458 }
459