xref: /openbmc/u-boot/drivers/mmc/mxsmmc.c (revision 14824105)
1 /*
2  * Freescale i.MX28 SSP MMC driver
3  *
4  * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
5  * on behalf of DENX Software Engineering GmbH
6  *
7  * Based on code from LTIB:
8  * (C) Copyright 2008-2010 Freescale Semiconductor, Inc.
9  * Terry Lv
10  *
11  * Copyright 2007, Freescale Semiconductor, Inc
12  * Andy Fleming
13  *
14  * Based vaguely on the pxa mmc code:
15  * (C) Copyright 2003
16  * Kyle Harris, Nexus Technologies, Inc. kharris@nexus-tech.net
17  *
18  * See file CREDITS for list of people who contributed to this
19  * project.
20  *
21  * This program is free software; you can redistribute it and/or
22  * modify it under the terms of the GNU General Public License as
23  * published by the Free Software Foundation; either version 2 of
24  * the License, or (at your option) any later version.
25  *
26  * This program is distributed in the hope that it will be useful,
27  * but WITHOUT ANY WARRANTY; without even the implied warranty of
28  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
29  * GNU General Public License for more details.
30  *
31  * You should have received a copy of the GNU General Public License
32  * along with this program; if not, write to the Free Software
33  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
34  * MA 02111-1307 USA
35  */
36 #include <common.h>
37 #include <malloc.h>
38 #include <mmc.h>
39 #include <asm/errno.h>
40 #include <asm/io.h>
41 #include <asm/arch/clock.h>
42 #include <asm/arch/imx-regs.h>
43 #include <asm/arch/sys_proto.h>
44 #include <asm/arch/dma.h>
45 
46 struct mxsmmc_priv {
47 	int			id;
48 	struct mx28_ssp_regs	*regs;
49 	uint32_t		clkseq_bypass;
50 	uint32_t		*clkctrl_ssp;
51 	uint32_t		buswidth;
52 	int			(*mmc_is_wp)(int);
53 	struct mxs_dma_desc	*desc;
54 };
55 
56 #define	MXSMMC_MAX_TIMEOUT	10000
57 
58 /*
59  * Sends a command out on the bus.  Takes the mmc pointer,
60  * a command pointer, and an optional data pointer.
61  */
62 static int
63 mxsmmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data)
64 {
65 	struct mxsmmc_priv *priv = (struct mxsmmc_priv *)mmc->priv;
66 	struct mx28_ssp_regs *ssp_regs = priv->regs;
67 	uint32_t reg;
68 	int timeout;
69 	uint32_t data_count, cache_data_count;
70 	uint32_t ctrl0;
71 
72 	debug("MMC%d: CMD%d\n", mmc->block_dev.dev, cmd->cmdidx);
73 
74 	/* Check bus busy */
75 	timeout = MXSMMC_MAX_TIMEOUT;
76 	while (--timeout) {
77 		udelay(1000);
78 		reg = readl(&ssp_regs->hw_ssp_status);
79 		if (!(reg &
80 			(SSP_STATUS_BUSY | SSP_STATUS_DATA_BUSY |
81 			SSP_STATUS_CMD_BUSY))) {
82 			break;
83 		}
84 	}
85 
86 	if (!timeout) {
87 		printf("MMC%d: Bus busy timeout!\n", mmc->block_dev.dev);
88 		return TIMEOUT;
89 	}
90 
91 	/* See if card is present */
92 	if (readl(&ssp_regs->hw_ssp_status) & SSP_STATUS_CARD_DETECT) {
93 		printf("MMC%d: No card detected!\n", mmc->block_dev.dev);
94 		return NO_CARD_ERR;
95 	}
96 
97 	/* Start building CTRL0 contents */
98 	ctrl0 = priv->buswidth;
99 
100 	/* Set up command */
101 	if (!(cmd->resp_type & MMC_RSP_CRC))
102 		ctrl0 |= SSP_CTRL0_IGNORE_CRC;
103 	if (cmd->resp_type & MMC_RSP_PRESENT)	/* Need to get response */
104 		ctrl0 |= SSP_CTRL0_GET_RESP;
105 	if (cmd->resp_type & MMC_RSP_136)	/* It's a 136 bits response */
106 		ctrl0 |= SSP_CTRL0_LONG_RESP;
107 
108 	/* Command index */
109 	reg = readl(&ssp_regs->hw_ssp_cmd0);
110 	reg &= ~(SSP_CMD0_CMD_MASK | SSP_CMD0_APPEND_8CYC);
111 	reg |= cmd->cmdidx << SSP_CMD0_CMD_OFFSET;
112 	if (cmd->cmdidx == MMC_CMD_STOP_TRANSMISSION)
113 		reg |= SSP_CMD0_APPEND_8CYC;
114 	writel(reg, &ssp_regs->hw_ssp_cmd0);
115 
116 	/* Command argument */
117 	writel(cmd->cmdarg, &ssp_regs->hw_ssp_cmd1);
118 
119 	/* Set up data */
120 	if (data) {
121 		/* READ or WRITE */
122 		if (data->flags & MMC_DATA_READ) {
123 			ctrl0 |= SSP_CTRL0_READ;
124 		} else if (priv->mmc_is_wp(mmc->block_dev.dev)) {
125 			printf("MMC%d: Can not write a locked card!\n",
126 				mmc->block_dev.dev);
127 			return UNUSABLE_ERR;
128 		}
129 
130 		ctrl0 |= SSP_CTRL0_DATA_XFER;
131 		reg = ((data->blocks - 1) <<
132 			SSP_BLOCK_SIZE_BLOCK_COUNT_OFFSET) |
133 			((ffs(data->blocksize) - 1) <<
134 			SSP_BLOCK_SIZE_BLOCK_SIZE_OFFSET);
135 		writel(reg, &ssp_regs->hw_ssp_block_size);
136 
137 		reg = data->blocksize * data->blocks;
138 		writel(reg, &ssp_regs->hw_ssp_xfer_size);
139 	}
140 
141 	/* Kick off the command */
142 	ctrl0 |= SSP_CTRL0_WAIT_FOR_IRQ | SSP_CTRL0_ENABLE | SSP_CTRL0_RUN;
143 	writel(ctrl0, &ssp_regs->hw_ssp_ctrl0);
144 
145 	/* Wait for the command to complete */
146 	timeout = MXSMMC_MAX_TIMEOUT;
147 	while (--timeout) {
148 		udelay(1000);
149 		reg = readl(&ssp_regs->hw_ssp_status);
150 		if (!(reg & SSP_STATUS_CMD_BUSY))
151 			break;
152 	}
153 
154 	if (!timeout) {
155 		printf("MMC%d: Command %d busy\n",
156 			mmc->block_dev.dev, cmd->cmdidx);
157 		return TIMEOUT;
158 	}
159 
160 	/* Check command timeout */
161 	if (reg & SSP_STATUS_RESP_TIMEOUT) {
162 		printf("MMC%d: Command %d timeout (status 0x%08x)\n",
163 			mmc->block_dev.dev, cmd->cmdidx, reg);
164 		return TIMEOUT;
165 	}
166 
167 	/* Check command errors */
168 	if (reg & (SSP_STATUS_RESP_CRC_ERR | SSP_STATUS_RESP_ERR)) {
169 		printf("MMC%d: Command %d error (status 0x%08x)!\n",
170 			mmc->block_dev.dev, cmd->cmdidx, reg);
171 		return COMM_ERR;
172 	}
173 
174 	/* Copy response to response buffer */
175 	if (cmd->resp_type & MMC_RSP_136) {
176 		cmd->response[3] = readl(&ssp_regs->hw_ssp_sdresp0);
177 		cmd->response[2] = readl(&ssp_regs->hw_ssp_sdresp1);
178 		cmd->response[1] = readl(&ssp_regs->hw_ssp_sdresp2);
179 		cmd->response[0] = readl(&ssp_regs->hw_ssp_sdresp3);
180 	} else
181 		cmd->response[0] = readl(&ssp_regs->hw_ssp_sdresp0);
182 
183 	/* Return if no data to process */
184 	if (!data)
185 		return 0;
186 
187 	data_count = data->blocksize * data->blocks;
188 
189 	if (data_count % ARCH_DMA_MINALIGN)
190 		cache_data_count = roundup(data_count, ARCH_DMA_MINALIGN);
191 	else
192 		cache_data_count = data_count;
193 
194 	if (data->flags & MMC_DATA_READ) {
195 		priv->desc->cmd.data = MXS_DMA_DESC_COMMAND_DMA_WRITE;
196 		priv->desc->cmd.address = (dma_addr_t)data->dest;
197 	} else {
198 		priv->desc->cmd.data = MXS_DMA_DESC_COMMAND_DMA_READ;
199 		priv->desc->cmd.address = (dma_addr_t)data->src;
200 
201 		/* Flush data to DRAM so DMA can pick them up */
202 		flush_dcache_range((uint32_t)priv->desc->cmd.address,
203 			(uint32_t)(priv->desc->cmd.address + cache_data_count));
204 	}
205 
206 	priv->desc->cmd.data |= MXS_DMA_DESC_IRQ | MXS_DMA_DESC_DEC_SEM |
207 				(data_count << MXS_DMA_DESC_BYTES_OFFSET);
208 
209 
210 	mxs_dma_desc_append(MXS_DMA_CHANNEL_AHB_APBH_SSP0, priv->desc);
211 	if (mxs_dma_go(MXS_DMA_CHANNEL_AHB_APBH_SSP0)) {
212 		printf("MMC%d: DMA transfer failed\n", mmc->block_dev.dev);
213 		return COMM_ERR;
214 	}
215 
216 	/* The data arrived into DRAM, invalidate cache over them */
217 	if (data->flags & MMC_DATA_READ) {
218 		invalidate_dcache_range((uint32_t)priv->desc->cmd.address,
219 			(uint32_t)(priv->desc->cmd.address + cache_data_count));
220 	}
221 
222 	/* Check data errors */
223 	reg = readl(&ssp_regs->hw_ssp_status);
224 	if (reg &
225 		(SSP_STATUS_TIMEOUT | SSP_STATUS_DATA_CRC_ERR |
226 		SSP_STATUS_FIFO_OVRFLW | SSP_STATUS_FIFO_UNDRFLW)) {
227 		printf("MMC%d: Data error with command %d (status 0x%08x)!\n",
228 			mmc->block_dev.dev, cmd->cmdidx, reg);
229 		return COMM_ERR;
230 	}
231 
232 	return 0;
233 }
234 
235 static void mxsmmc_set_ios(struct mmc *mmc)
236 {
237 	struct mxsmmc_priv *priv = (struct mxsmmc_priv *)mmc->priv;
238 	struct mx28_ssp_regs *ssp_regs = priv->regs;
239 
240 	/* Set the clock speed */
241 	if (mmc->clock)
242 		mx28_set_ssp_busclock(priv->id, mmc->clock / 1000);
243 
244 	switch (mmc->bus_width) {
245 	case 1:
246 		priv->buswidth = SSP_CTRL0_BUS_WIDTH_ONE_BIT;
247 		break;
248 	case 4:
249 		priv->buswidth = SSP_CTRL0_BUS_WIDTH_FOUR_BIT;
250 		break;
251 	case 8:
252 		priv->buswidth = SSP_CTRL0_BUS_WIDTH_EIGHT_BIT;
253 		break;
254 	}
255 
256 	/* Set the bus width */
257 	clrsetbits_le32(&ssp_regs->hw_ssp_ctrl0,
258 			SSP_CTRL0_BUS_WIDTH_MASK, priv->buswidth);
259 
260 	debug("MMC%d: Set %d bits bus width\n",
261 		mmc->block_dev.dev, mmc->bus_width);
262 }
263 
264 static int mxsmmc_init(struct mmc *mmc)
265 {
266 	struct mxsmmc_priv *priv = (struct mxsmmc_priv *)mmc->priv;
267 	struct mx28_ssp_regs *ssp_regs = priv->regs;
268 
269 	/* Reset SSP */
270 	mx28_reset_block(&ssp_regs->hw_ssp_ctrl0_reg);
271 
272 	/* 8 bits word length in MMC mode */
273 	clrsetbits_le32(&ssp_regs->hw_ssp_ctrl1,
274 		SSP_CTRL1_SSP_MODE_MASK | SSP_CTRL1_WORD_LENGTH_MASK,
275 		SSP_CTRL1_SSP_MODE_SD_MMC | SSP_CTRL1_WORD_LENGTH_EIGHT_BITS |
276 		SSP_CTRL1_DMA_ENABLE);
277 
278 	/* Set initial bit clock 400 KHz */
279 	mx28_set_ssp_busclock(priv->id, 400);
280 
281 	/* Send initial 74 clock cycles (185 us @ 400 KHz)*/
282 	writel(SSP_CMD0_CONT_CLKING_EN, &ssp_regs->hw_ssp_cmd0_set);
283 	udelay(200);
284 	writel(SSP_CMD0_CONT_CLKING_EN, &ssp_regs->hw_ssp_cmd0_clr);
285 
286 	return 0;
287 }
288 
289 int mxsmmc_initialize(bd_t *bis, int id, int (*wp)(int))
290 {
291 	struct mx28_clkctrl_regs *clkctrl_regs =
292 		(struct mx28_clkctrl_regs *)MXS_CLKCTRL_BASE;
293 	struct mmc *mmc = NULL;
294 	struct mxsmmc_priv *priv = NULL;
295 
296 	mmc = malloc(sizeof(struct mmc));
297 	if (!mmc)
298 		return -ENOMEM;
299 
300 	priv = malloc(sizeof(struct mxsmmc_priv));
301 	if (!priv) {
302 		free(mmc);
303 		return -ENOMEM;
304 	}
305 
306 	priv->desc = mxs_dma_desc_alloc();
307 	if (!priv->desc) {
308 		free(priv);
309 		free(mmc);
310 		return -ENOMEM;
311 	}
312 
313 	priv->mmc_is_wp = wp;
314 	priv->id = id;
315 	switch (id) {
316 	case 0:
317 		priv->regs = (struct mx28_ssp_regs *)MXS_SSP0_BASE;
318 		priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP0;
319 		priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp0;
320 		break;
321 	case 1:
322 		priv->regs = (struct mx28_ssp_regs *)MXS_SSP1_BASE;
323 		priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP1;
324 		priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp1;
325 		break;
326 	case 2:
327 		priv->regs = (struct mx28_ssp_regs *)MXS_SSP2_BASE;
328 		priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP2;
329 		priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp2;
330 		break;
331 	case 3:
332 		priv->regs = (struct mx28_ssp_regs *)MXS_SSP3_BASE;
333 		priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP3;
334 		priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp3;
335 		break;
336 	}
337 
338 	sprintf(mmc->name, "MXS MMC");
339 	mmc->send_cmd = mxsmmc_send_cmd;
340 	mmc->set_ios = mxsmmc_set_ios;
341 	mmc->init = mxsmmc_init;
342 	mmc->getcd = NULL;
343 	mmc->priv = priv;
344 
345 	mmc->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
346 
347 	mmc->host_caps = MMC_MODE_4BIT | MMC_MODE_8BIT |
348 			 MMC_MODE_HS_52MHz | MMC_MODE_HS;
349 
350 	/*
351 	 * SSPCLK = 480 * 18 / 29 / 1 = 297.731 MHz
352 	 * SSP bit rate = SSPCLK / (CLOCK_DIVIDE * (1 + CLOCK_RATE)),
353 	 * CLOCK_DIVIDE has to be an even value from 2 to 254, and
354 	 * CLOCK_RATE could be any integer from 0 to 255.
355 	 */
356 	mmc->f_min = 400000;
357 	mmc->f_max = mxc_get_clock(MXC_SSP0_CLK + id) * 1000 / 2;
358 	mmc->b_max = 0x40;
359 
360 	mmc_register(mmc);
361 	return 0;
362 }
363