xref: /openbmc/u-boot/drivers/mmc/gen_atmel_mci.c (revision 7ca6f363)
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 <asm/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 static int initialized = 0;
36 
37 /* Read Atmel MCI IP version */
38 static unsigned int atmel_mci_get_version(struct atmel_mci *mci)
39 {
40 	return readl(&mci->version) & 0x00000fff;
41 }
42 
43 /*
44  * Print command and status:
45  *
46  * - always when DEBUG is defined
47  * - on command errors
48  */
49 static void dump_cmd(u32 cmdr, u32 arg, u32 status, const char* msg)
50 {
51 	printf("gen_atmel_mci: CMDR %08x (%2u) ARGR %08x (SR: %08x) %s\n",
52 		cmdr, cmdr&0x3F, arg, status, msg);
53 }
54 
55 /* Setup for MCI Clock and Block Size */
56 static void mci_set_mode(struct mmc *mmc, u32 hz, u32 blklen)
57 {
58 	atmel_mci_t *mci = (atmel_mci_t *)mmc->priv;
59 	u32 bus_hz = get_mci_clk_rate();
60 	u32 clkdiv = 255;
61 
62 	debug("mci: bus_hz is %u, setting clock %u Hz, block size %u\n",
63 		bus_hz, hz, blklen);
64 	if (hz > 0) {
65 		/* find lowest clkdiv yielding a rate <= than requested */
66 		for (clkdiv=0; clkdiv<255; clkdiv++) {
67 			if ((bus_hz / (clkdiv+1) / 2) <= hz)
68 				break;
69 		}
70 	}
71 	printf("mci: setting clock %u Hz, block size %u\n",
72 		(bus_hz / (clkdiv+1)) / 2, blklen);
73 
74 	blklen &= 0xfffc;
75 	/* On some platforms RDPROOF and WRPROOF are ignored */
76 	writel((MMCI_BF(CLKDIV, clkdiv)
77 		 | MMCI_BF(BLKLEN, blklen)
78 		 | MMCI_BIT(RDPROOF)
79 		 | MMCI_BIT(WRPROOF)), &mci->mr);
80 	/*
81 	 * On some new platforms BLKLEN in mci->mr is ignored.
82 	 * Should use the BLKLEN in the block register.
83 	 */
84 	writel(MMCI_BF(BLKLEN, blklen), &mci->blkr);
85 	initialized = 1;
86 }
87 
88 /* Return the CMDR with flags for a given command and data packet */
89 static u32 mci_encode_cmd(
90 	struct mmc_cmd *cmd, struct mmc_data *data, u32* error_flags)
91 {
92 	u32 cmdr = 0;
93 
94 	/* Default Flags for Errors */
95 	*error_flags |= (MMCI_BIT(DTOE) | MMCI_BIT(RDIRE) | MMCI_BIT(RENDE) |
96 		MMCI_BIT(RINDE) | MMCI_BIT(RTOE));
97 
98 	/* Default Flags for the Command */
99 	cmdr |= MMCI_BIT(MAXLAT);
100 
101 	if (data) {
102 		cmdr |= MMCI_BF(TRCMD, 1);
103 		if (data->blocks > 1)
104 			cmdr |= MMCI_BF(TRTYP, 1);
105 		if (data->flags & MMC_DATA_READ)
106 			cmdr |= MMCI_BIT(TRDIR);
107 	}
108 
109 	if (cmd->resp_type & MMC_RSP_CRC)
110 		*error_flags |= MMCI_BIT(RCRCE);
111 	if (cmd->resp_type & MMC_RSP_136)
112 		cmdr |= MMCI_BF(RSPTYP, 2);
113 	else if (cmd->resp_type & MMC_RSP_BUSY)
114 		cmdr |= MMCI_BF(RSPTYP, 3);
115 	else if (cmd->resp_type & MMC_RSP_PRESENT)
116 		cmdr |= MMCI_BF(RSPTYP, 1);
117 
118 	return cmdr | MMCI_BF(CMDNB, cmd->cmdidx);
119 }
120 
121 /* Entered into function pointer in mci_send_cmd */
122 static u32 mci_data_read(atmel_mci_t *mci, u32* data, u32 error_flags)
123 {
124 	u32 status;
125 
126 	do {
127 		status = readl(&mci->sr);
128 		if (status & (error_flags | MMCI_BIT(OVRE)))
129 			goto io_fail;
130 	} while (!(status & MMCI_BIT(RXRDY)));
131 
132 	if (status & MMCI_BIT(RXRDY)) {
133 		*data = readl(&mci->rdr);
134 		status = 0;
135 	}
136 io_fail:
137 	return status;
138 }
139 
140 /* Entered into function pointer in mci_send_cmd */
141 static u32 mci_data_write(atmel_mci_t *mci, u32* data, u32 error_flags)
142 {
143 	u32 status;
144 
145 	do {
146 		status = readl(&mci->sr);
147 		if (status & (error_flags | MMCI_BIT(UNRE)))
148 			goto io_fail;
149 	} while (!(status & MMCI_BIT(TXRDY)));
150 
151 	if (status & MMCI_BIT(TXRDY)) {
152 		writel(*data, &mci->tdr);
153 		status = 0;
154 	}
155 io_fail:
156 	return status;
157 }
158 
159 /*
160  * Entered into mmc structure during driver init
161  *
162  * Sends a command out on the bus and deals with the block data.
163  * Takes the mmc pointer, a command pointer, and an optional data pointer.
164  */
165 static int
166 mci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data)
167 {
168 	atmel_mci_t *mci = (atmel_mci_t *)mmc->priv;
169 	u32 cmdr;
170 	u32 error_flags = 0;
171 	u32 status;
172 
173 	if (!initialized) {
174 		puts ("MCI not initialized!\n");
175 		return COMM_ERR;
176 	}
177 
178 	/* Figure out the transfer arguments */
179 	cmdr = mci_encode_cmd(cmd, data, &error_flags);
180 
181 	/* For multi blocks read/write, set the block register */
182 	if ((cmd->cmdidx == MMC_CMD_READ_MULTIPLE_BLOCK)
183 			|| (cmd->cmdidx == MMC_CMD_WRITE_MULTIPLE_BLOCK))
184 		writel(data->blocks | MMCI_BF(BLKLEN, mmc->read_bl_len),
185 			&mci->blkr);
186 
187 	/* Send the command */
188 	writel(cmd->cmdarg, &mci->argr);
189 	writel(cmdr, &mci->cmdr);
190 
191 #ifdef DEBUG
192 	dump_cmd(cmdr, cmd->cmdarg, 0, "DEBUG");
193 #endif
194 
195 	/* Wait for the command to complete */
196 	while (!((status = readl(&mci->sr)) & MMCI_BIT(CMDRDY)));
197 
198 	if ((status & error_flags) & MMCI_BIT(RTOE)) {
199 		dump_cmd(cmdr, cmd->cmdarg, status, "Command Time Out");
200 		return TIMEOUT;
201 	} else if (status & error_flags) {
202 		dump_cmd(cmdr, cmd->cmdarg, status, "Command Failed");
203 		return COMM_ERR;
204 	}
205 
206 	/* Copy the response to the response buffer */
207 	if (cmd->resp_type & MMC_RSP_136) {
208 		cmd->response[0] = readl(&mci->rspr);
209 		cmd->response[1] = readl(&mci->rspr1);
210 		cmd->response[2] = readl(&mci->rspr2);
211 		cmd->response[3] = readl(&mci->rspr3);
212 	} else
213 		cmd->response[0] = readl(&mci->rspr);
214 
215 	/* transfer all of the blocks */
216 	if (data) {
217 		u32 word_count, block_count;
218 		u32* ioptr;
219 		u32 sys_blocksize, dummy, i;
220 		u32 (*mci_data_op)
221 			(atmel_mci_t *mci, u32* data, u32 error_flags);
222 
223 		if (data->flags & MMC_DATA_READ) {
224 			mci_data_op = mci_data_read;
225 			sys_blocksize = mmc->read_bl_len;
226 			ioptr = (u32*)data->dest;
227 		} else {
228 			mci_data_op = mci_data_write;
229 			sys_blocksize = mmc->write_bl_len;
230 			ioptr = (u32*)data->src;
231 		}
232 
233 		status = 0;
234 		for (block_count = 0;
235 				block_count < data->blocks && !status;
236 				block_count++) {
237 			word_count = 0;
238 			do {
239 				status = mci_data_op(mci, ioptr, error_flags);
240 				word_count++;
241 				ioptr++;
242 			} while (!status && word_count < (data->blocksize/4));
243 #ifdef DEBUG
244 			if (data->flags & MMC_DATA_READ)
245 			{
246 				printf("Read Data:\n");
247 				print_buffer(0, data->dest, 1,
248 					word_count*4, 0);
249 			}
250 #endif
251 #ifdef DEBUG
252 			if (!status && word_count < (sys_blocksize / 4))
253 				printf("filling rest of block...\n");
254 #endif
255 			/* fill the rest of a full block */
256 			while (!status && word_count < (sys_blocksize / 4)) {
257 				status = mci_data_op(mci, &dummy,
258 					error_flags);
259 				word_count++;
260 			}
261 			if (status) {
262 				dump_cmd(cmdr, cmd->cmdarg, status,
263 					"Data Transfer Failed");
264 				return COMM_ERR;
265 			}
266 		}
267 
268 		/* Wait for Transfer End */
269 		i = 0;
270 		do {
271 			status = readl(&mci->sr);
272 
273 			if (status & error_flags) {
274 				dump_cmd(cmdr, cmd->cmdarg, status,
275 					"DTIP Wait Failed");
276 				return COMM_ERR;
277 			}
278 			i++;
279 		} while ((status & MMCI_BIT(DTIP)) && i < 10000);
280 		if (status & MMCI_BIT(DTIP)) {
281 			dump_cmd(cmdr, cmd->cmdarg, status,
282 				"XFER DTIP never unset, ignoring");
283 		}
284 	}
285 
286 	return 0;
287 }
288 
289 /* Entered into mmc structure during driver init */
290 static void mci_set_ios(struct mmc *mmc)
291 {
292 	atmel_mci_t *mci = (atmel_mci_t *)mmc->priv;
293 	int bus_width = mmc->bus_width;
294 	unsigned int version = atmel_mci_get_version(mci);
295 	int busw;
296 
297 	/* Set the clock speed */
298 	mci_set_mode(mmc, mmc->clock, MMC_DEFAULT_BLKLEN);
299 
300 	/*
301 	 * set the bus width and select slot for this interface
302 	 * there is no capability for multiple slots on the same interface yet
303 	 */
304 	if ((version & 0xf00) >= 0x300) {
305 		switch (bus_width) {
306 		case 8:
307 			busw = 3;
308 			break;
309 		case 4:
310 			busw = 2;
311 			break;
312 		default:
313 			busw = 0;
314 			break;
315 		}
316 
317 		writel(busw << 6 | MMCI_BF(SCDSEL, MCI_BUS), &mci->sdcr);
318 	} else {
319 		busw = (bus_width == 4) ? 1 : 0;
320 
321 		writel(busw << 7 | MMCI_BF(SCDSEL, MCI_BUS), &mci->sdcr);
322 	}
323 }
324 
325 /* Entered into mmc structure during driver init */
326 static int mci_init(struct mmc *mmc)
327 {
328 	atmel_mci_t *mci = (atmel_mci_t *)mmc->priv;
329 
330 	/* Initialize controller */
331 	writel(MMCI_BIT(SWRST), &mci->cr);	/* soft reset */
332 	writel(MMCI_BIT(PWSDIS), &mci->cr);	/* disable power save */
333 	writel(MMCI_BIT(MCIEN), &mci->cr);	/* enable mci */
334 	writel(MMCI_BF(SCDSEL, MCI_BUS), &mci->sdcr);	/* select port */
335 
336 	/* This delay can be optimized, but stick with max value */
337 	writel(0x7f, &mci->dtor);
338 	/* Disable Interrupts */
339 	writel(~0UL, &mci->idr);
340 
341 	/* Set default clocks and blocklen */
342 	mci_set_mode(mmc, CONFIG_SYS_MMC_CLK_OD, MMC_DEFAULT_BLKLEN);
343 
344 	return 0;
345 }
346 
347 /*
348  * This is the only exported function
349  *
350  * Call it with the MCI register base address
351  */
352 int atmel_mci_init(void *regs)
353 {
354 	struct mmc *mmc = malloc(sizeof(struct mmc));
355 	struct atmel_mci *mci;
356 	unsigned int version;
357 
358 	if (!mmc)
359 		return -1;
360 
361 	strcpy(mmc->name, "mci");
362 	mmc->priv = regs;
363 	mmc->send_cmd = mci_send_cmd;
364 	mmc->set_ios = mci_set_ios;
365 	mmc->init = mci_init;
366 	mmc->getcd = NULL;
367 	mmc->getwp = NULL;
368 
369 	/* need to be able to pass these in on a board by board basis */
370 	mmc->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
371 	mci = (struct atmel_mci *)mmc->priv;
372 	version = atmel_mci_get_version(mci);
373 	if ((version & 0xf00) >= 0x300)
374 		mmc->host_caps = MMC_MODE_8BIT;
375 
376 	mmc->host_caps |= MMC_MODE_4BIT;
377 
378 	/*
379 	 * min and max frequencies determined by
380 	 * max and min of clock divider
381 	 */
382 	mmc->f_min = get_mci_clk_rate() / (2*256);
383 	mmc->f_max = get_mci_clk_rate() / (2*1);
384 
385 	mmc->b_max = 0;
386 
387 	mmc_register(mmc);
388 
389 	return 0;
390 }
391