xref: /linux/drivers/mmc/host/davinci_mmc.c (revision e24bce8fb4c26bd0d8eca74cbbee1ad049246be3)
1 /*
2  * davinci_mmc.c - TI DaVinci MMC/SD/SDIO driver
3  *
4  * Copyright (C) 2006 Texas Instruments.
5  *       Original author: Purushotam Kumar
6  * Copyright (C) 2009 David Brownell
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  */
22 
23 #include <linux/module.h>
24 #include <linux/ioport.h>
25 #include <linux/platform_device.h>
26 #include <linux/clk.h>
27 #include <linux/err.h>
28 #include <linux/cpufreq.h>
29 #include <linux/mmc/host.h>
30 #include <linux/io.h>
31 #include <linux/irq.h>
32 #include <linux/delay.h>
33 #include <linux/dmaengine.h>
34 #include <linux/dma-mapping.h>
35 #include <linux/mmc/mmc.h>
36 #include <linux/of.h>
37 #include <linux/of_device.h>
38 #include <linux/mmc/slot-gpio.h>
39 #include <linux/interrupt.h>
40 
41 #include <linux/platform_data/mmc-davinci.h>
42 
43 /*
44  * Register Definitions
45  */
46 #define DAVINCI_MMCCTL       0x00 /* Control Register                  */
47 #define DAVINCI_MMCCLK       0x04 /* Memory Clock Control Register     */
48 #define DAVINCI_MMCST0       0x08 /* Status Register 0                 */
49 #define DAVINCI_MMCST1       0x0C /* Status Register 1                 */
50 #define DAVINCI_MMCIM        0x10 /* Interrupt Mask Register           */
51 #define DAVINCI_MMCTOR       0x14 /* Response Time-Out Register        */
52 #define DAVINCI_MMCTOD       0x18 /* Data Read Time-Out Register       */
53 #define DAVINCI_MMCBLEN      0x1C /* Block Length Register             */
54 #define DAVINCI_MMCNBLK      0x20 /* Number of Blocks Register         */
55 #define DAVINCI_MMCNBLC      0x24 /* Number of Blocks Counter Register */
56 #define DAVINCI_MMCDRR       0x28 /* Data Receive Register             */
57 #define DAVINCI_MMCDXR       0x2C /* Data Transmit Register            */
58 #define DAVINCI_MMCCMD       0x30 /* Command Register                  */
59 #define DAVINCI_MMCARGHL     0x34 /* Argument Register                 */
60 #define DAVINCI_MMCRSP01     0x38 /* Response Register 0 and 1         */
61 #define DAVINCI_MMCRSP23     0x3C /* Response Register 0 and 1         */
62 #define DAVINCI_MMCRSP45     0x40 /* Response Register 0 and 1         */
63 #define DAVINCI_MMCRSP67     0x44 /* Response Register 0 and 1         */
64 #define DAVINCI_MMCDRSP      0x48 /* Data Response Register            */
65 #define DAVINCI_MMCETOK      0x4C
66 #define DAVINCI_MMCCIDX      0x50 /* Command Index Register            */
67 #define DAVINCI_MMCCKC       0x54
68 #define DAVINCI_MMCTORC      0x58
69 #define DAVINCI_MMCTODC      0x5C
70 #define DAVINCI_MMCBLNC      0x60
71 #define DAVINCI_SDIOCTL      0x64
72 #define DAVINCI_SDIOST0      0x68
73 #define DAVINCI_SDIOIEN      0x6C
74 #define DAVINCI_SDIOIST      0x70
75 #define DAVINCI_MMCFIFOCTL   0x74 /* FIFO Control Register             */
76 
77 /* DAVINCI_MMCCTL definitions */
78 #define MMCCTL_DATRST         (1 << 0)
79 #define MMCCTL_CMDRST         (1 << 1)
80 #define MMCCTL_WIDTH_8_BIT    (1 << 8)
81 #define MMCCTL_WIDTH_4_BIT    (1 << 2)
82 #define MMCCTL_DATEG_DISABLED (0 << 6)
83 #define MMCCTL_DATEG_RISING   (1 << 6)
84 #define MMCCTL_DATEG_FALLING  (2 << 6)
85 #define MMCCTL_DATEG_BOTH     (3 << 6)
86 #define MMCCTL_PERMDR_LE      (0 << 9)
87 #define MMCCTL_PERMDR_BE      (1 << 9)
88 #define MMCCTL_PERMDX_LE      (0 << 10)
89 #define MMCCTL_PERMDX_BE      (1 << 10)
90 
91 /* DAVINCI_MMCCLK definitions */
92 #define MMCCLK_CLKEN          (1 << 8)
93 #define MMCCLK_CLKRT_MASK     (0xFF << 0)
94 
95 /* IRQ bit definitions, for DAVINCI_MMCST0 and DAVINCI_MMCIM */
96 #define MMCST0_DATDNE         BIT(0)	/* data done */
97 #define MMCST0_BSYDNE         BIT(1)	/* busy done */
98 #define MMCST0_RSPDNE         BIT(2)	/* command done */
99 #define MMCST0_TOUTRD         BIT(3)	/* data read timeout */
100 #define MMCST0_TOUTRS         BIT(4)	/* command response timeout */
101 #define MMCST0_CRCWR          BIT(5)	/* data write CRC error */
102 #define MMCST0_CRCRD          BIT(6)	/* data read CRC error */
103 #define MMCST0_CRCRS          BIT(7)	/* command response CRC error */
104 #define MMCST0_DXRDY          BIT(9)	/* data transmit ready (fifo empty) */
105 #define MMCST0_DRRDY          BIT(10)	/* data receive ready (data in fifo)*/
106 #define MMCST0_DATED          BIT(11)	/* DAT3 edge detect */
107 #define MMCST0_TRNDNE         BIT(12)	/* transfer done */
108 
109 /* DAVINCI_MMCST1 definitions */
110 #define MMCST1_BUSY           (1 << 0)
111 
112 /* DAVINCI_MMCCMD definitions */
113 #define MMCCMD_CMD_MASK       (0x3F << 0)
114 #define MMCCMD_PPLEN          (1 << 7)
115 #define MMCCMD_BSYEXP         (1 << 8)
116 #define MMCCMD_RSPFMT_MASK    (3 << 9)
117 #define MMCCMD_RSPFMT_NONE    (0 << 9)
118 #define MMCCMD_RSPFMT_R1456   (1 << 9)
119 #define MMCCMD_RSPFMT_R2      (2 << 9)
120 #define MMCCMD_RSPFMT_R3      (3 << 9)
121 #define MMCCMD_DTRW           (1 << 11)
122 #define MMCCMD_STRMTP         (1 << 12)
123 #define MMCCMD_WDATX          (1 << 13)
124 #define MMCCMD_INITCK         (1 << 14)
125 #define MMCCMD_DCLR           (1 << 15)
126 #define MMCCMD_DMATRIG        (1 << 16)
127 
128 /* DAVINCI_MMCFIFOCTL definitions */
129 #define MMCFIFOCTL_FIFORST    (1 << 0)
130 #define MMCFIFOCTL_FIFODIR_WR (1 << 1)
131 #define MMCFIFOCTL_FIFODIR_RD (0 << 1)
132 #define MMCFIFOCTL_FIFOLEV    (1 << 2) /* 0 = 128 bits, 1 = 256 bits */
133 #define MMCFIFOCTL_ACCWD_4    (0 << 3) /* access width of 4 bytes    */
134 #define MMCFIFOCTL_ACCWD_3    (1 << 3) /* access width of 3 bytes    */
135 #define MMCFIFOCTL_ACCWD_2    (2 << 3) /* access width of 2 bytes    */
136 #define MMCFIFOCTL_ACCWD_1    (3 << 3) /* access width of 1 byte     */
137 
138 /* DAVINCI_SDIOST0 definitions */
139 #define SDIOST0_DAT1_HI       BIT(0)
140 
141 /* DAVINCI_SDIOIEN definitions */
142 #define SDIOIEN_IOINTEN       BIT(0)
143 
144 /* DAVINCI_SDIOIST definitions */
145 #define SDIOIST_IOINT         BIT(0)
146 
147 /* MMCSD Init clock in Hz in opendrain mode */
148 #define MMCSD_INIT_CLOCK		200000
149 
150 /*
151  * One scatterlist dma "segment" is at most MAX_CCNT rw_threshold units,
152  * and we handle up to MAX_NR_SG segments.  MMC_BLOCK_BOUNCE kicks in only
153  * for drivers with max_segs == 1, making the segments bigger (64KB)
154  * than the page or two that's otherwise typical. nr_sg (passed from
155  * platform data) == 16 gives at least the same throughput boost, using
156  * EDMA transfer linkage instead of spending CPU time copying pages.
157  */
158 #define MAX_CCNT	((1 << 16) - 1)
159 
160 #define MAX_NR_SG	16
161 
162 static unsigned rw_threshold = 32;
163 module_param(rw_threshold, uint, S_IRUGO);
164 MODULE_PARM_DESC(rw_threshold,
165 		"Read/Write threshold. Default = 32");
166 
167 static unsigned poll_threshold = 128;
168 module_param(poll_threshold, uint, S_IRUGO);
169 MODULE_PARM_DESC(poll_threshold,
170 		 "Polling transaction size threshold. Default = 128");
171 
172 static unsigned poll_loopcount = 32;
173 module_param(poll_loopcount, uint, S_IRUGO);
174 MODULE_PARM_DESC(poll_loopcount,
175 		 "Maximum polling loop count. Default = 32");
176 
177 static unsigned __initdata use_dma = 1;
178 module_param(use_dma, uint, 0);
179 MODULE_PARM_DESC(use_dma, "Whether to use DMA or not. Default = 1");
180 
181 struct mmc_davinci_host {
182 	struct mmc_command *cmd;
183 	struct mmc_data *data;
184 	struct mmc_host *mmc;
185 	struct clk *clk;
186 	unsigned int mmc_input_clk;
187 	void __iomem *base;
188 	struct resource *mem_res;
189 	int mmc_irq, sdio_irq;
190 	unsigned char bus_mode;
191 
192 #define DAVINCI_MMC_DATADIR_NONE	0
193 #define DAVINCI_MMC_DATADIR_READ	1
194 #define DAVINCI_MMC_DATADIR_WRITE	2
195 	unsigned char data_dir;
196 
197 	/* buffer is used during PIO of one scatterlist segment, and
198 	 * is updated along with buffer_bytes_left.  bytes_left applies
199 	 * to all N blocks of the PIO transfer.
200 	 */
201 	u8 *buffer;
202 	u32 buffer_bytes_left;
203 	u32 bytes_left;
204 
205 	struct dma_chan *dma_tx;
206 	struct dma_chan *dma_rx;
207 	bool use_dma;
208 	bool do_dma;
209 	bool sdio_int;
210 	bool active_request;
211 
212 	/* For PIO we walk scatterlists one segment at a time. */
213 	unsigned int		sg_len;
214 	struct scatterlist *sg;
215 
216 	/* Version of the MMC/SD controller */
217 	u8 version;
218 	/* for ns in one cycle calculation */
219 	unsigned ns_in_one_cycle;
220 	/* Number of sg segments */
221 	u8 nr_sg;
222 #ifdef CONFIG_CPU_FREQ
223 	struct notifier_block	freq_transition;
224 #endif
225 };
226 
227 static irqreturn_t mmc_davinci_irq(int irq, void *dev_id);
228 
229 /* PIO only */
230 static void mmc_davinci_sg_to_buf(struct mmc_davinci_host *host)
231 {
232 	host->buffer_bytes_left = sg_dma_len(host->sg);
233 	host->buffer = sg_virt(host->sg);
234 	if (host->buffer_bytes_left > host->bytes_left)
235 		host->buffer_bytes_left = host->bytes_left;
236 }
237 
238 static void davinci_fifo_data_trans(struct mmc_davinci_host *host,
239 					unsigned int n)
240 {
241 	u8 *p;
242 	unsigned int i;
243 
244 	if (host->buffer_bytes_left == 0) {
245 		host->sg = sg_next(host->data->sg);
246 		mmc_davinci_sg_to_buf(host);
247 	}
248 
249 	p = host->buffer;
250 	if (n > host->buffer_bytes_left)
251 		n = host->buffer_bytes_left;
252 	host->buffer_bytes_left -= n;
253 	host->bytes_left -= n;
254 
255 	/* NOTE:  we never transfer more than rw_threshold bytes
256 	 * to/from the fifo here; there's no I/O overlap.
257 	 * This also assumes that access width( i.e. ACCWD) is 4 bytes
258 	 */
259 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE) {
260 		for (i = 0; i < (n >> 2); i++) {
261 			writel(*((u32 *)p), host->base + DAVINCI_MMCDXR);
262 			p = p + 4;
263 		}
264 		if (n & 3) {
265 			iowrite8_rep(host->base + DAVINCI_MMCDXR, p, (n & 3));
266 			p = p + (n & 3);
267 		}
268 	} else {
269 		for (i = 0; i < (n >> 2); i++) {
270 			*((u32 *)p) = readl(host->base + DAVINCI_MMCDRR);
271 			p  = p + 4;
272 		}
273 		if (n & 3) {
274 			ioread8_rep(host->base + DAVINCI_MMCDRR, p, (n & 3));
275 			p = p + (n & 3);
276 		}
277 	}
278 	host->buffer = p;
279 }
280 
281 static void mmc_davinci_start_command(struct mmc_davinci_host *host,
282 		struct mmc_command *cmd)
283 {
284 	u32 cmd_reg = 0;
285 	u32 im_val;
286 
287 	dev_dbg(mmc_dev(host->mmc), "CMD%d, arg 0x%08x%s\n",
288 		cmd->opcode, cmd->arg,
289 		({ char *s;
290 		switch (mmc_resp_type(cmd)) {
291 		case MMC_RSP_R1:
292 			s = ", R1/R5/R6/R7 response";
293 			break;
294 		case MMC_RSP_R1B:
295 			s = ", R1b response";
296 			break;
297 		case MMC_RSP_R2:
298 			s = ", R2 response";
299 			break;
300 		case MMC_RSP_R3:
301 			s = ", R3/R4 response";
302 			break;
303 		default:
304 			s = ", (R? response)";
305 			break;
306 		}; s; }));
307 	host->cmd = cmd;
308 
309 	switch (mmc_resp_type(cmd)) {
310 	case MMC_RSP_R1B:
311 		/* There's some spec confusion about when R1B is
312 		 * allowed, but if the card doesn't issue a BUSY
313 		 * then it's harmless for us to allow it.
314 		 */
315 		cmd_reg |= MMCCMD_BSYEXP;
316 		/* FALLTHROUGH */
317 	case MMC_RSP_R1:		/* 48 bits, CRC */
318 		cmd_reg |= MMCCMD_RSPFMT_R1456;
319 		break;
320 	case MMC_RSP_R2:		/* 136 bits, CRC */
321 		cmd_reg |= MMCCMD_RSPFMT_R2;
322 		break;
323 	case MMC_RSP_R3:		/* 48 bits, no CRC */
324 		cmd_reg |= MMCCMD_RSPFMT_R3;
325 		break;
326 	default:
327 		cmd_reg |= MMCCMD_RSPFMT_NONE;
328 		dev_dbg(mmc_dev(host->mmc), "unknown resp_type %04x\n",
329 			mmc_resp_type(cmd));
330 		break;
331 	}
332 
333 	/* Set command index */
334 	cmd_reg |= cmd->opcode;
335 
336 	/* Enable EDMA transfer triggers */
337 	if (host->do_dma)
338 		cmd_reg |= MMCCMD_DMATRIG;
339 
340 	if (host->version == MMC_CTLR_VERSION_2 && host->data != NULL &&
341 			host->data_dir == DAVINCI_MMC_DATADIR_READ)
342 		cmd_reg |= MMCCMD_DMATRIG;
343 
344 	/* Setting whether command involves data transfer or not */
345 	if (cmd->data)
346 		cmd_reg |= MMCCMD_WDATX;
347 
348 	/* Setting whether data read or write */
349 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE)
350 		cmd_reg |= MMCCMD_DTRW;
351 
352 	if (host->bus_mode == MMC_BUSMODE_PUSHPULL)
353 		cmd_reg |= MMCCMD_PPLEN;
354 
355 	/* set Command timeout */
356 	writel(0x1FFF, host->base + DAVINCI_MMCTOR);
357 
358 	/* Enable interrupt (calculate here, defer until FIFO is stuffed). */
359 	im_val =  MMCST0_RSPDNE | MMCST0_CRCRS | MMCST0_TOUTRS;
360 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE) {
361 		im_val |= MMCST0_DATDNE | MMCST0_CRCWR;
362 
363 		if (!host->do_dma)
364 			im_val |= MMCST0_DXRDY;
365 	} else if (host->data_dir == DAVINCI_MMC_DATADIR_READ) {
366 		im_val |= MMCST0_DATDNE | MMCST0_CRCRD | MMCST0_TOUTRD;
367 
368 		if (!host->do_dma)
369 			im_val |= MMCST0_DRRDY;
370 	}
371 
372 	/*
373 	 * Before non-DMA WRITE commands the controller needs priming:
374 	 * FIFO should be populated with 32 bytes i.e. whatever is the FIFO size
375 	 */
376 	if (!host->do_dma && (host->data_dir == DAVINCI_MMC_DATADIR_WRITE))
377 		davinci_fifo_data_trans(host, rw_threshold);
378 
379 	writel(cmd->arg, host->base + DAVINCI_MMCARGHL);
380 	writel(cmd_reg,  host->base + DAVINCI_MMCCMD);
381 
382 	host->active_request = true;
383 
384 	if (!host->do_dma && host->bytes_left <= poll_threshold) {
385 		u32 count = poll_loopcount;
386 
387 		while (host->active_request && count--) {
388 			mmc_davinci_irq(0, host);
389 			cpu_relax();
390 		}
391 	}
392 
393 	if (host->active_request)
394 		writel(im_val, host->base + DAVINCI_MMCIM);
395 }
396 
397 /*----------------------------------------------------------------------*/
398 
399 /* DMA infrastructure */
400 
401 static void davinci_abort_dma(struct mmc_davinci_host *host)
402 {
403 	struct dma_chan *sync_dev;
404 
405 	if (host->data_dir == DAVINCI_MMC_DATADIR_READ)
406 		sync_dev = host->dma_rx;
407 	else
408 		sync_dev = host->dma_tx;
409 
410 	dmaengine_terminate_all(sync_dev);
411 }
412 
413 static int mmc_davinci_send_dma_request(struct mmc_davinci_host *host,
414 		struct mmc_data *data)
415 {
416 	struct dma_chan *chan;
417 	struct dma_async_tx_descriptor *desc;
418 	int ret = 0;
419 
420 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE) {
421 		struct dma_slave_config dma_tx_conf = {
422 			.direction = DMA_MEM_TO_DEV,
423 			.dst_addr = host->mem_res->start + DAVINCI_MMCDXR,
424 			.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
425 			.dst_maxburst =
426 				rw_threshold / DMA_SLAVE_BUSWIDTH_4_BYTES,
427 		};
428 		chan = host->dma_tx;
429 		dmaengine_slave_config(host->dma_tx, &dma_tx_conf);
430 
431 		desc = dmaengine_prep_slave_sg(host->dma_tx,
432 				data->sg,
433 				host->sg_len,
434 				DMA_MEM_TO_DEV,
435 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
436 		if (!desc) {
437 			dev_dbg(mmc_dev(host->mmc),
438 				"failed to allocate DMA TX descriptor");
439 			ret = -1;
440 			goto out;
441 		}
442 	} else {
443 		struct dma_slave_config dma_rx_conf = {
444 			.direction = DMA_DEV_TO_MEM,
445 			.src_addr = host->mem_res->start + DAVINCI_MMCDRR,
446 			.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
447 			.src_maxburst =
448 				rw_threshold / DMA_SLAVE_BUSWIDTH_4_BYTES,
449 		};
450 		chan = host->dma_rx;
451 		dmaengine_slave_config(host->dma_rx, &dma_rx_conf);
452 
453 		desc = dmaengine_prep_slave_sg(host->dma_rx,
454 				data->sg,
455 				host->sg_len,
456 				DMA_DEV_TO_MEM,
457 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
458 		if (!desc) {
459 			dev_dbg(mmc_dev(host->mmc),
460 				"failed to allocate DMA RX descriptor");
461 			ret = -1;
462 			goto out;
463 		}
464 	}
465 
466 	dmaengine_submit(desc);
467 	dma_async_issue_pending(chan);
468 
469 out:
470 	return ret;
471 }
472 
473 static int mmc_davinci_start_dma_transfer(struct mmc_davinci_host *host,
474 		struct mmc_data *data)
475 {
476 	int i;
477 	int mask = rw_threshold - 1;
478 	int ret = 0;
479 
480 	host->sg_len = dma_map_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
481 				((data->flags & MMC_DATA_WRITE)
482 				? DMA_TO_DEVICE
483 				: DMA_FROM_DEVICE));
484 
485 	/* no individual DMA segment should need a partial FIFO */
486 	for (i = 0; i < host->sg_len; i++) {
487 		if (sg_dma_len(data->sg + i) & mask) {
488 			dma_unmap_sg(mmc_dev(host->mmc),
489 					data->sg, data->sg_len,
490 					(data->flags & MMC_DATA_WRITE)
491 					? DMA_TO_DEVICE
492 					: DMA_FROM_DEVICE);
493 			return -1;
494 		}
495 	}
496 
497 	host->do_dma = 1;
498 	ret = mmc_davinci_send_dma_request(host, data);
499 
500 	return ret;
501 }
502 
503 static void __init_or_module
504 davinci_release_dma_channels(struct mmc_davinci_host *host)
505 {
506 	if (!host->use_dma)
507 		return;
508 
509 	dma_release_channel(host->dma_tx);
510 	dma_release_channel(host->dma_rx);
511 }
512 
513 static int __init davinci_acquire_dma_channels(struct mmc_davinci_host *host)
514 {
515 	host->dma_tx = dma_request_chan(mmc_dev(host->mmc), "tx");
516 	if (IS_ERR(host->dma_tx)) {
517 		dev_err(mmc_dev(host->mmc), "Can't get dma_tx channel\n");
518 		return PTR_ERR(host->dma_tx);
519 	}
520 
521 	host->dma_rx = dma_request_chan(mmc_dev(host->mmc), "rx");
522 	if (IS_ERR(host->dma_rx)) {
523 		dev_err(mmc_dev(host->mmc), "Can't get dma_rx channel\n");
524 		dma_release_channel(host->dma_tx);
525 		return PTR_ERR(host->dma_rx);
526 	}
527 
528 	return 0;
529 }
530 
531 /*----------------------------------------------------------------------*/
532 
533 static void
534 mmc_davinci_prepare_data(struct mmc_davinci_host *host, struct mmc_request *req)
535 {
536 	int fifo_lev = (rw_threshold == 32) ? MMCFIFOCTL_FIFOLEV : 0;
537 	int timeout;
538 	struct mmc_data *data = req->data;
539 
540 	if (host->version == MMC_CTLR_VERSION_2)
541 		fifo_lev = (rw_threshold == 64) ? MMCFIFOCTL_FIFOLEV : 0;
542 
543 	host->data = data;
544 	if (data == NULL) {
545 		host->data_dir = DAVINCI_MMC_DATADIR_NONE;
546 		writel(0, host->base + DAVINCI_MMCBLEN);
547 		writel(0, host->base + DAVINCI_MMCNBLK);
548 		return;
549 	}
550 
551 	dev_dbg(mmc_dev(host->mmc), "%s, %d blocks of %d bytes\n",
552 		(data->flags & MMC_DATA_WRITE) ? "write" : "read",
553 		data->blocks, data->blksz);
554 	dev_dbg(mmc_dev(host->mmc), "  DTO %d cycles + %d ns\n",
555 		data->timeout_clks, data->timeout_ns);
556 	timeout = data->timeout_clks +
557 		(data->timeout_ns / host->ns_in_one_cycle);
558 	if (timeout > 0xffff)
559 		timeout = 0xffff;
560 
561 	writel(timeout, host->base + DAVINCI_MMCTOD);
562 	writel(data->blocks, host->base + DAVINCI_MMCNBLK);
563 	writel(data->blksz, host->base + DAVINCI_MMCBLEN);
564 
565 	/* Configure the FIFO */
566 	if (data->flags & MMC_DATA_WRITE) {
567 		host->data_dir = DAVINCI_MMC_DATADIR_WRITE;
568 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_WR | MMCFIFOCTL_FIFORST,
569 			host->base + DAVINCI_MMCFIFOCTL);
570 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_WR,
571 			host->base + DAVINCI_MMCFIFOCTL);
572 	} else {
573 		host->data_dir = DAVINCI_MMC_DATADIR_READ;
574 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_RD | MMCFIFOCTL_FIFORST,
575 			host->base + DAVINCI_MMCFIFOCTL);
576 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_RD,
577 			host->base + DAVINCI_MMCFIFOCTL);
578 	}
579 
580 	host->buffer = NULL;
581 	host->bytes_left = data->blocks * data->blksz;
582 
583 	/* For now we try to use DMA whenever we won't need partial FIFO
584 	 * reads or writes, either for the whole transfer (as tested here)
585 	 * or for any individual scatterlist segment (tested when we call
586 	 * start_dma_transfer).
587 	 *
588 	 * While we *could* change that, unusual block sizes are rarely
589 	 * used.  The occasional fallback to PIO should't hurt.
590 	 */
591 	if (host->use_dma && (host->bytes_left & (rw_threshold - 1)) == 0
592 			&& mmc_davinci_start_dma_transfer(host, data) == 0) {
593 		/* zero this to ensure we take no PIO paths */
594 		host->bytes_left = 0;
595 	} else {
596 		/* Revert to CPU Copy */
597 		host->sg_len = data->sg_len;
598 		host->sg = host->data->sg;
599 		mmc_davinci_sg_to_buf(host);
600 	}
601 }
602 
603 static void mmc_davinci_request(struct mmc_host *mmc, struct mmc_request *req)
604 {
605 	struct mmc_davinci_host *host = mmc_priv(mmc);
606 	unsigned long timeout = jiffies + msecs_to_jiffies(900);
607 	u32 mmcst1 = 0;
608 
609 	/* Card may still be sending BUSY after a previous operation,
610 	 * typically some kind of write.  If so, we can't proceed yet.
611 	 */
612 	while (time_before(jiffies, timeout)) {
613 		mmcst1  = readl(host->base + DAVINCI_MMCST1);
614 		if (!(mmcst1 & MMCST1_BUSY))
615 			break;
616 		cpu_relax();
617 	}
618 	if (mmcst1 & MMCST1_BUSY) {
619 		dev_err(mmc_dev(host->mmc), "still BUSY? bad ... \n");
620 		req->cmd->error = -ETIMEDOUT;
621 		mmc_request_done(mmc, req);
622 		return;
623 	}
624 
625 	host->do_dma = 0;
626 	mmc_davinci_prepare_data(host, req);
627 	mmc_davinci_start_command(host, req->cmd);
628 }
629 
630 static unsigned int calculate_freq_for_card(struct mmc_davinci_host *host,
631 	unsigned int mmc_req_freq)
632 {
633 	unsigned int mmc_freq = 0, mmc_pclk = 0, mmc_push_pull_divisor = 0;
634 
635 	mmc_pclk = host->mmc_input_clk;
636 	if (mmc_req_freq && mmc_pclk > (2 * mmc_req_freq))
637 		mmc_push_pull_divisor = ((unsigned int)mmc_pclk
638 				/ (2 * mmc_req_freq)) - 1;
639 	else
640 		mmc_push_pull_divisor = 0;
641 
642 	mmc_freq = (unsigned int)mmc_pclk
643 		/ (2 * (mmc_push_pull_divisor + 1));
644 
645 	if (mmc_freq > mmc_req_freq)
646 		mmc_push_pull_divisor = mmc_push_pull_divisor + 1;
647 	/* Convert ns to clock cycles */
648 	if (mmc_req_freq <= 400000)
649 		host->ns_in_one_cycle = (1000000) / (((mmc_pclk
650 				/ (2 * (mmc_push_pull_divisor + 1)))/1000));
651 	else
652 		host->ns_in_one_cycle = (1000000) / (((mmc_pclk
653 				/ (2 * (mmc_push_pull_divisor + 1)))/1000000));
654 
655 	return mmc_push_pull_divisor;
656 }
657 
658 static void calculate_clk_divider(struct mmc_host *mmc, struct mmc_ios *ios)
659 {
660 	unsigned int open_drain_freq = 0, mmc_pclk = 0;
661 	unsigned int mmc_push_pull_freq = 0;
662 	struct mmc_davinci_host *host = mmc_priv(mmc);
663 
664 	if (ios->bus_mode == MMC_BUSMODE_OPENDRAIN) {
665 		u32 temp;
666 
667 		/* Ignoring the init clock value passed for fixing the inter
668 		 * operability with different cards.
669 		 */
670 		open_drain_freq = ((unsigned int)mmc_pclk
671 				/ (2 * MMCSD_INIT_CLOCK)) - 1;
672 
673 		if (open_drain_freq > 0xFF)
674 			open_drain_freq = 0xFF;
675 
676 		temp = readl(host->base + DAVINCI_MMCCLK) & ~MMCCLK_CLKRT_MASK;
677 		temp |= open_drain_freq;
678 		writel(temp, host->base + DAVINCI_MMCCLK);
679 
680 		/* Convert ns to clock cycles */
681 		host->ns_in_one_cycle = (1000000) / (MMCSD_INIT_CLOCK/1000);
682 	} else {
683 		u32 temp;
684 		mmc_push_pull_freq = calculate_freq_for_card(host, ios->clock);
685 
686 		if (mmc_push_pull_freq > 0xFF)
687 			mmc_push_pull_freq = 0xFF;
688 
689 		temp = readl(host->base + DAVINCI_MMCCLK) & ~MMCCLK_CLKEN;
690 		writel(temp, host->base + DAVINCI_MMCCLK);
691 
692 		udelay(10);
693 
694 		temp = readl(host->base + DAVINCI_MMCCLK) & ~MMCCLK_CLKRT_MASK;
695 		temp |= mmc_push_pull_freq;
696 		writel(temp, host->base + DAVINCI_MMCCLK);
697 
698 		writel(temp | MMCCLK_CLKEN, host->base + DAVINCI_MMCCLK);
699 
700 		udelay(10);
701 	}
702 }
703 
704 static void mmc_davinci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
705 {
706 	struct mmc_davinci_host *host = mmc_priv(mmc);
707 	struct platform_device *pdev = to_platform_device(mmc->parent);
708 	struct davinci_mmc_config *config = pdev->dev.platform_data;
709 
710 	dev_dbg(mmc_dev(host->mmc),
711 		"clock %dHz busmode %d powermode %d Vdd %04x\n",
712 		ios->clock, ios->bus_mode, ios->power_mode,
713 		ios->vdd);
714 
715 	switch (ios->power_mode) {
716 	case MMC_POWER_OFF:
717 		if (config && config->set_power)
718 			config->set_power(pdev->id, false);
719 		break;
720 	case MMC_POWER_UP:
721 		if (config && config->set_power)
722 			config->set_power(pdev->id, true);
723 		break;
724 	}
725 
726 	switch (ios->bus_width) {
727 	case MMC_BUS_WIDTH_8:
728 		dev_dbg(mmc_dev(host->mmc), "Enabling 8 bit mode\n");
729 		writel((readl(host->base + DAVINCI_MMCCTL) &
730 			~MMCCTL_WIDTH_4_BIT) | MMCCTL_WIDTH_8_BIT,
731 			host->base + DAVINCI_MMCCTL);
732 		break;
733 	case MMC_BUS_WIDTH_4:
734 		dev_dbg(mmc_dev(host->mmc), "Enabling 4 bit mode\n");
735 		if (host->version == MMC_CTLR_VERSION_2)
736 			writel((readl(host->base + DAVINCI_MMCCTL) &
737 				~MMCCTL_WIDTH_8_BIT) | MMCCTL_WIDTH_4_BIT,
738 				host->base + DAVINCI_MMCCTL);
739 		else
740 			writel(readl(host->base + DAVINCI_MMCCTL) |
741 				MMCCTL_WIDTH_4_BIT,
742 				host->base + DAVINCI_MMCCTL);
743 		break;
744 	case MMC_BUS_WIDTH_1:
745 		dev_dbg(mmc_dev(host->mmc), "Enabling 1 bit mode\n");
746 		if (host->version == MMC_CTLR_VERSION_2)
747 			writel(readl(host->base + DAVINCI_MMCCTL) &
748 				~(MMCCTL_WIDTH_8_BIT | MMCCTL_WIDTH_4_BIT),
749 				host->base + DAVINCI_MMCCTL);
750 		else
751 			writel(readl(host->base + DAVINCI_MMCCTL) &
752 				~MMCCTL_WIDTH_4_BIT,
753 				host->base + DAVINCI_MMCCTL);
754 		break;
755 	}
756 
757 	calculate_clk_divider(mmc, ios);
758 
759 	host->bus_mode = ios->bus_mode;
760 	if (ios->power_mode == MMC_POWER_UP) {
761 		unsigned long timeout = jiffies + msecs_to_jiffies(50);
762 		bool lose = true;
763 
764 		/* Send clock cycles, poll completion */
765 		writel(0, host->base + DAVINCI_MMCARGHL);
766 		writel(MMCCMD_INITCK, host->base + DAVINCI_MMCCMD);
767 		while (time_before(jiffies, timeout)) {
768 			u32 tmp = readl(host->base + DAVINCI_MMCST0);
769 
770 			if (tmp & MMCST0_RSPDNE) {
771 				lose = false;
772 				break;
773 			}
774 			cpu_relax();
775 		}
776 		if (lose)
777 			dev_warn(mmc_dev(host->mmc), "powerup timeout\n");
778 	}
779 
780 	/* FIXME on power OFF, reset things ... */
781 }
782 
783 static void
784 mmc_davinci_xfer_done(struct mmc_davinci_host *host, struct mmc_data *data)
785 {
786 	host->data = NULL;
787 
788 	if (host->mmc->caps & MMC_CAP_SDIO_IRQ) {
789 		/*
790 		 * SDIO Interrupt Detection work-around as suggested by
791 		 * Davinci Errata (TMS320DM355 Silicon Revision 1.1 Errata
792 		 * 2.1.6): Signal SDIO interrupt only if it is enabled by core
793 		 */
794 		if (host->sdio_int && !(readl(host->base + DAVINCI_SDIOST0) &
795 					SDIOST0_DAT1_HI)) {
796 			writel(SDIOIST_IOINT, host->base + DAVINCI_SDIOIST);
797 			mmc_signal_sdio_irq(host->mmc);
798 		}
799 	}
800 
801 	if (host->do_dma) {
802 		davinci_abort_dma(host);
803 
804 		dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
805 			     (data->flags & MMC_DATA_WRITE)
806 			     ? DMA_TO_DEVICE
807 			     : DMA_FROM_DEVICE);
808 		host->do_dma = false;
809 	}
810 	host->data_dir = DAVINCI_MMC_DATADIR_NONE;
811 
812 	if (!data->stop || (host->cmd && host->cmd->error)) {
813 		mmc_request_done(host->mmc, data->mrq);
814 		writel(0, host->base + DAVINCI_MMCIM);
815 		host->active_request = false;
816 	} else
817 		mmc_davinci_start_command(host, data->stop);
818 }
819 
820 static void mmc_davinci_cmd_done(struct mmc_davinci_host *host,
821 				 struct mmc_command *cmd)
822 {
823 	host->cmd = NULL;
824 
825 	if (cmd->flags & MMC_RSP_PRESENT) {
826 		if (cmd->flags & MMC_RSP_136) {
827 			/* response type 2 */
828 			cmd->resp[3] = readl(host->base + DAVINCI_MMCRSP01);
829 			cmd->resp[2] = readl(host->base + DAVINCI_MMCRSP23);
830 			cmd->resp[1] = readl(host->base + DAVINCI_MMCRSP45);
831 			cmd->resp[0] = readl(host->base + DAVINCI_MMCRSP67);
832 		} else {
833 			/* response types 1, 1b, 3, 4, 5, 6 */
834 			cmd->resp[0] = readl(host->base + DAVINCI_MMCRSP67);
835 		}
836 	}
837 
838 	if (host->data == NULL || cmd->error) {
839 		if (cmd->error == -ETIMEDOUT)
840 			cmd->mrq->cmd->retries = 0;
841 		mmc_request_done(host->mmc, cmd->mrq);
842 		writel(0, host->base + DAVINCI_MMCIM);
843 		host->active_request = false;
844 	}
845 }
846 
847 static inline void mmc_davinci_reset_ctrl(struct mmc_davinci_host *host,
848 								int val)
849 {
850 	u32 temp;
851 
852 	temp = readl(host->base + DAVINCI_MMCCTL);
853 	if (val)	/* reset */
854 		temp |= MMCCTL_CMDRST | MMCCTL_DATRST;
855 	else		/* enable */
856 		temp &= ~(MMCCTL_CMDRST | MMCCTL_DATRST);
857 
858 	writel(temp, host->base + DAVINCI_MMCCTL);
859 	udelay(10);
860 }
861 
862 static void
863 davinci_abort_data(struct mmc_davinci_host *host, struct mmc_data *data)
864 {
865 	mmc_davinci_reset_ctrl(host, 1);
866 	mmc_davinci_reset_ctrl(host, 0);
867 }
868 
869 static irqreturn_t mmc_davinci_sdio_irq(int irq, void *dev_id)
870 {
871 	struct mmc_davinci_host *host = dev_id;
872 	unsigned int status;
873 
874 	status = readl(host->base + DAVINCI_SDIOIST);
875 	if (status & SDIOIST_IOINT) {
876 		dev_dbg(mmc_dev(host->mmc),
877 			"SDIO interrupt status %x\n", status);
878 		writel(status | SDIOIST_IOINT, host->base + DAVINCI_SDIOIST);
879 		mmc_signal_sdio_irq(host->mmc);
880 	}
881 	return IRQ_HANDLED;
882 }
883 
884 static irqreturn_t mmc_davinci_irq(int irq, void *dev_id)
885 {
886 	struct mmc_davinci_host *host = (struct mmc_davinci_host *)dev_id;
887 	unsigned int status, qstatus;
888 	int end_command = 0;
889 	int end_transfer = 0;
890 	struct mmc_data *data = host->data;
891 
892 	if (host->cmd == NULL && host->data == NULL) {
893 		status = readl(host->base + DAVINCI_MMCST0);
894 		dev_dbg(mmc_dev(host->mmc),
895 			"Spurious interrupt 0x%04x\n", status);
896 		/* Disable the interrupt from mmcsd */
897 		writel(0, host->base + DAVINCI_MMCIM);
898 		return IRQ_NONE;
899 	}
900 
901 	status = readl(host->base + DAVINCI_MMCST0);
902 	qstatus = status;
903 
904 	/* handle FIFO first when using PIO for data.
905 	 * bytes_left will decrease to zero as I/O progress and status will
906 	 * read zero over iteration because this controller status
907 	 * register(MMCST0) reports any status only once and it is cleared
908 	 * by read. So, it is not unbouned loop even in the case of
909 	 * non-dma.
910 	 */
911 	if (host->bytes_left && (status & (MMCST0_DXRDY | MMCST0_DRRDY))) {
912 		unsigned long im_val;
913 
914 		/*
915 		 * If interrupts fire during the following loop, they will be
916 		 * handled by the handler, but the PIC will still buffer these.
917 		 * As a result, the handler will be called again to serve these
918 		 * needlessly. In order to avoid these spurious interrupts,
919 		 * keep interrupts masked during the loop.
920 		 */
921 		im_val = readl(host->base + DAVINCI_MMCIM);
922 		writel(0, host->base + DAVINCI_MMCIM);
923 
924 		do {
925 			davinci_fifo_data_trans(host, rw_threshold);
926 			status = readl(host->base + DAVINCI_MMCST0);
927 			qstatus |= status;
928 		} while (host->bytes_left &&
929 			 (status & (MMCST0_DXRDY | MMCST0_DRRDY)));
930 
931 		/*
932 		 * If an interrupt is pending, it is assumed it will fire when
933 		 * it is unmasked. This assumption is also taken when the MMCIM
934 		 * is first set. Otherwise, writing to MMCIM after reading the
935 		 * status is race-prone.
936 		 */
937 		writel(im_val, host->base + DAVINCI_MMCIM);
938 	}
939 
940 	if (qstatus & MMCST0_DATDNE) {
941 		/* All blocks sent/received, and CRC checks passed */
942 		if (data != NULL) {
943 			if ((host->do_dma == 0) && (host->bytes_left > 0)) {
944 				/* if datasize < rw_threshold
945 				 * no RX ints are generated
946 				 */
947 				davinci_fifo_data_trans(host, host->bytes_left);
948 			}
949 			end_transfer = 1;
950 			data->bytes_xfered = data->blocks * data->blksz;
951 		} else {
952 			dev_err(mmc_dev(host->mmc),
953 					"DATDNE with no host->data\n");
954 		}
955 	}
956 
957 	if (qstatus & MMCST0_TOUTRD) {
958 		/* Read data timeout */
959 		data->error = -ETIMEDOUT;
960 		end_transfer = 1;
961 
962 		dev_dbg(mmc_dev(host->mmc),
963 			"read data timeout, status %x\n",
964 			qstatus);
965 
966 		davinci_abort_data(host, data);
967 	}
968 
969 	if (qstatus & (MMCST0_CRCWR | MMCST0_CRCRD)) {
970 		/* Data CRC error */
971 		data->error = -EILSEQ;
972 		end_transfer = 1;
973 
974 		/* NOTE:  this controller uses CRCWR to report both CRC
975 		 * errors and timeouts (on writes).  MMCDRSP values are
976 		 * only weakly documented, but 0x9f was clearly a timeout
977 		 * case and the two three-bit patterns in various SD specs
978 		 * (101, 010) aren't part of it ...
979 		 */
980 		if (qstatus & MMCST0_CRCWR) {
981 			u32 temp = readb(host->base + DAVINCI_MMCDRSP);
982 
983 			if (temp == 0x9f)
984 				data->error = -ETIMEDOUT;
985 		}
986 		dev_dbg(mmc_dev(host->mmc), "data %s %s error\n",
987 			(qstatus & MMCST0_CRCWR) ? "write" : "read",
988 			(data->error == -ETIMEDOUT) ? "timeout" : "CRC");
989 
990 		davinci_abort_data(host, data);
991 	}
992 
993 	if (qstatus & MMCST0_TOUTRS) {
994 		/* Command timeout */
995 		if (host->cmd) {
996 			dev_dbg(mmc_dev(host->mmc),
997 				"CMD%d timeout, status %x\n",
998 				host->cmd->opcode, qstatus);
999 			host->cmd->error = -ETIMEDOUT;
1000 			if (data) {
1001 				end_transfer = 1;
1002 				davinci_abort_data(host, data);
1003 			} else
1004 				end_command = 1;
1005 		}
1006 	}
1007 
1008 	if (qstatus & MMCST0_CRCRS) {
1009 		/* Command CRC error */
1010 		dev_dbg(mmc_dev(host->mmc), "Command CRC error\n");
1011 		if (host->cmd) {
1012 			host->cmd->error = -EILSEQ;
1013 			end_command = 1;
1014 		}
1015 	}
1016 
1017 	if (qstatus & MMCST0_RSPDNE) {
1018 		/* End of command phase */
1019 		end_command = (int) host->cmd;
1020 	}
1021 
1022 	if (end_command)
1023 		mmc_davinci_cmd_done(host, host->cmd);
1024 	if (end_transfer)
1025 		mmc_davinci_xfer_done(host, data);
1026 	return IRQ_HANDLED;
1027 }
1028 
1029 static int mmc_davinci_get_cd(struct mmc_host *mmc)
1030 {
1031 	struct platform_device *pdev = to_platform_device(mmc->parent);
1032 	struct davinci_mmc_config *config = pdev->dev.platform_data;
1033 
1034 	if (config && config->get_cd)
1035 		return config->get_cd(pdev->id);
1036 
1037 	return mmc_gpio_get_cd(mmc);
1038 }
1039 
1040 static int mmc_davinci_get_ro(struct mmc_host *mmc)
1041 {
1042 	struct platform_device *pdev = to_platform_device(mmc->parent);
1043 	struct davinci_mmc_config *config = pdev->dev.platform_data;
1044 
1045 	if (config && config->get_ro)
1046 		return config->get_ro(pdev->id);
1047 
1048 	return mmc_gpio_get_ro(mmc);
1049 }
1050 
1051 static void mmc_davinci_enable_sdio_irq(struct mmc_host *mmc, int enable)
1052 {
1053 	struct mmc_davinci_host *host = mmc_priv(mmc);
1054 
1055 	if (enable) {
1056 		if (!(readl(host->base + DAVINCI_SDIOST0) & SDIOST0_DAT1_HI)) {
1057 			writel(SDIOIST_IOINT, host->base + DAVINCI_SDIOIST);
1058 			mmc_signal_sdio_irq(host->mmc);
1059 		} else {
1060 			host->sdio_int = true;
1061 			writel(readl(host->base + DAVINCI_SDIOIEN) |
1062 			       SDIOIEN_IOINTEN, host->base + DAVINCI_SDIOIEN);
1063 		}
1064 	} else {
1065 		host->sdio_int = false;
1066 		writel(readl(host->base + DAVINCI_SDIOIEN) & ~SDIOIEN_IOINTEN,
1067 		       host->base + DAVINCI_SDIOIEN);
1068 	}
1069 }
1070 
1071 static struct mmc_host_ops mmc_davinci_ops = {
1072 	.request	= mmc_davinci_request,
1073 	.set_ios	= mmc_davinci_set_ios,
1074 	.get_cd		= mmc_davinci_get_cd,
1075 	.get_ro		= mmc_davinci_get_ro,
1076 	.enable_sdio_irq = mmc_davinci_enable_sdio_irq,
1077 };
1078 
1079 /*----------------------------------------------------------------------*/
1080 
1081 #ifdef CONFIG_CPU_FREQ
1082 static int mmc_davinci_cpufreq_transition(struct notifier_block *nb,
1083 				     unsigned long val, void *data)
1084 {
1085 	struct mmc_davinci_host *host;
1086 	unsigned int mmc_pclk;
1087 	struct mmc_host *mmc;
1088 	unsigned long flags;
1089 
1090 	host = container_of(nb, struct mmc_davinci_host, freq_transition);
1091 	mmc = host->mmc;
1092 	mmc_pclk = clk_get_rate(host->clk);
1093 
1094 	if (val == CPUFREQ_POSTCHANGE) {
1095 		spin_lock_irqsave(&mmc->lock, flags);
1096 		host->mmc_input_clk = mmc_pclk;
1097 		calculate_clk_divider(mmc, &mmc->ios);
1098 		spin_unlock_irqrestore(&mmc->lock, flags);
1099 	}
1100 
1101 	return 0;
1102 }
1103 
1104 static inline int mmc_davinci_cpufreq_register(struct mmc_davinci_host *host)
1105 {
1106 	host->freq_transition.notifier_call = mmc_davinci_cpufreq_transition;
1107 
1108 	return cpufreq_register_notifier(&host->freq_transition,
1109 					 CPUFREQ_TRANSITION_NOTIFIER);
1110 }
1111 
1112 static inline void mmc_davinci_cpufreq_deregister(struct mmc_davinci_host *host)
1113 {
1114 	cpufreq_unregister_notifier(&host->freq_transition,
1115 				    CPUFREQ_TRANSITION_NOTIFIER);
1116 }
1117 #else
1118 static inline int mmc_davinci_cpufreq_register(struct mmc_davinci_host *host)
1119 {
1120 	return 0;
1121 }
1122 
1123 static inline void mmc_davinci_cpufreq_deregister(struct mmc_davinci_host *host)
1124 {
1125 }
1126 #endif
1127 static void __init init_mmcsd_host(struct mmc_davinci_host *host)
1128 {
1129 
1130 	mmc_davinci_reset_ctrl(host, 1);
1131 
1132 	writel(0, host->base + DAVINCI_MMCCLK);
1133 	writel(MMCCLK_CLKEN, host->base + DAVINCI_MMCCLK);
1134 
1135 	writel(0x1FFF, host->base + DAVINCI_MMCTOR);
1136 	writel(0xFFFF, host->base + DAVINCI_MMCTOD);
1137 
1138 	mmc_davinci_reset_ctrl(host, 0);
1139 }
1140 
1141 static const struct platform_device_id davinci_mmc_devtype[] = {
1142 	{
1143 		.name	= "dm6441-mmc",
1144 		.driver_data = MMC_CTLR_VERSION_1,
1145 	}, {
1146 		.name	= "da830-mmc",
1147 		.driver_data = MMC_CTLR_VERSION_2,
1148 	},
1149 	{},
1150 };
1151 MODULE_DEVICE_TABLE(platform, davinci_mmc_devtype);
1152 
1153 static const struct of_device_id davinci_mmc_dt_ids[] = {
1154 	{
1155 		.compatible = "ti,dm6441-mmc",
1156 		.data = &davinci_mmc_devtype[MMC_CTLR_VERSION_1],
1157 	},
1158 	{
1159 		.compatible = "ti,da830-mmc",
1160 		.data = &davinci_mmc_devtype[MMC_CTLR_VERSION_2],
1161 	},
1162 	{},
1163 };
1164 MODULE_DEVICE_TABLE(of, davinci_mmc_dt_ids);
1165 
1166 static int mmc_davinci_parse_pdata(struct mmc_host *mmc)
1167 {
1168 	struct platform_device *pdev = to_platform_device(mmc->parent);
1169 	struct davinci_mmc_config *pdata = pdev->dev.platform_data;
1170 	struct mmc_davinci_host *host;
1171 	int ret;
1172 
1173 	if (!pdata)
1174 		return -EINVAL;
1175 
1176 	host = mmc_priv(mmc);
1177 	if (!host)
1178 		return -EINVAL;
1179 
1180 	if (pdata && pdata->nr_sg)
1181 		host->nr_sg = pdata->nr_sg - 1;
1182 
1183 	if (pdata && (pdata->wires == 4 || pdata->wires == 0))
1184 		mmc->caps |= MMC_CAP_4_BIT_DATA;
1185 
1186 	if (pdata && (pdata->wires == 8))
1187 		mmc->caps |= (MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA);
1188 
1189 	mmc->f_min = 312500;
1190 	mmc->f_max = 25000000;
1191 	if (pdata && pdata->max_freq)
1192 		mmc->f_max = pdata->max_freq;
1193 	if (pdata && pdata->caps)
1194 		mmc->caps |= pdata->caps;
1195 
1196 	/* Register a cd gpio, if there is not one, enable polling */
1197 	ret = mmc_gpiod_request_cd(mmc, "cd", 0, false, 0, NULL);
1198 	if (ret == -EPROBE_DEFER)
1199 		return ret;
1200 	else if (ret)
1201 		mmc->caps |= MMC_CAP_NEEDS_POLL;
1202 
1203 	ret = mmc_gpiod_request_ro(mmc, "wp", 0, false, 0, NULL);
1204 	if (ret == -EPROBE_DEFER)
1205 		return ret;
1206 
1207 	return 0;
1208 }
1209 
1210 static int __init davinci_mmcsd_probe(struct platform_device *pdev)
1211 {
1212 	const struct of_device_id *match;
1213 	struct mmc_davinci_host *host = NULL;
1214 	struct mmc_host *mmc = NULL;
1215 	struct resource *r, *mem = NULL;
1216 	int ret, irq;
1217 	size_t mem_size;
1218 	const struct platform_device_id *id_entry;
1219 
1220 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1221 	if (!r)
1222 		return -ENODEV;
1223 	irq = platform_get_irq(pdev, 0);
1224 	if (irq < 0)
1225 		return irq;
1226 
1227 	mem_size = resource_size(r);
1228 	mem = devm_request_mem_region(&pdev->dev, r->start, mem_size,
1229 				      pdev->name);
1230 	if (!mem)
1231 		return -EBUSY;
1232 
1233 	mmc = mmc_alloc_host(sizeof(struct mmc_davinci_host), &pdev->dev);
1234 	if (!mmc)
1235 		return -ENOMEM;
1236 
1237 	host = mmc_priv(mmc);
1238 	host->mmc = mmc;	/* Important */
1239 
1240 	host->mem_res = mem;
1241 	host->base = devm_ioremap(&pdev->dev, mem->start, mem_size);
1242 	if (!host->base) {
1243 		ret = -ENOMEM;
1244 		goto ioremap_fail;
1245 	}
1246 
1247 	host->clk = devm_clk_get(&pdev->dev, NULL);
1248 	if (IS_ERR(host->clk)) {
1249 		ret = PTR_ERR(host->clk);
1250 		goto clk_get_fail;
1251 	}
1252 	ret = clk_prepare_enable(host->clk);
1253 	if (ret)
1254 		goto clk_prepare_enable_fail;
1255 
1256 	host->mmc_input_clk = clk_get_rate(host->clk);
1257 
1258 	match = of_match_device(davinci_mmc_dt_ids, &pdev->dev);
1259 	if (match) {
1260 		pdev->id_entry = match->data;
1261 		ret = mmc_of_parse(mmc);
1262 		if (ret) {
1263 			dev_err(&pdev->dev,
1264 				"could not parse of data: %d\n", ret);
1265 			goto parse_fail;
1266 		}
1267 	} else {
1268 		ret = mmc_davinci_parse_pdata(mmc);
1269 		if (ret) {
1270 			dev_err(&pdev->dev,
1271 				"could not parse platform data: %d\n", ret);
1272 			goto parse_fail;
1273 	}	}
1274 
1275 	if (host->nr_sg > MAX_NR_SG || !host->nr_sg)
1276 		host->nr_sg = MAX_NR_SG;
1277 
1278 	init_mmcsd_host(host);
1279 
1280 	host->use_dma = use_dma;
1281 	host->mmc_irq = irq;
1282 	host->sdio_irq = platform_get_irq(pdev, 1);
1283 
1284 	if (host->use_dma) {
1285 		ret = davinci_acquire_dma_channels(host);
1286 		if (ret == -EPROBE_DEFER)
1287 			goto dma_probe_defer;
1288 		else if (ret)
1289 			host->use_dma = 0;
1290 	}
1291 
1292 	mmc->caps |= MMC_CAP_WAIT_WHILE_BUSY;
1293 
1294 	id_entry = platform_get_device_id(pdev);
1295 	if (id_entry)
1296 		host->version = id_entry->driver_data;
1297 
1298 	mmc->ops = &mmc_davinci_ops;
1299 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1300 
1301 	/* With no iommu coalescing pages, each phys_seg is a hw_seg.
1302 	 * Each hw_seg uses one EDMA parameter RAM slot, always one
1303 	 * channel and then usually some linked slots.
1304 	 */
1305 	mmc->max_segs		= MAX_NR_SG;
1306 
1307 	/* EDMA limit per hw segment (one or two MBytes) */
1308 	mmc->max_seg_size	= MAX_CCNT * rw_threshold;
1309 
1310 	/* MMC/SD controller limits for multiblock requests */
1311 	mmc->max_blk_size	= 4095;  /* BLEN is 12 bits */
1312 	mmc->max_blk_count	= 65535; /* NBLK is 16 bits */
1313 	mmc->max_req_size	= mmc->max_blk_size * mmc->max_blk_count;
1314 
1315 	dev_dbg(mmc_dev(host->mmc), "max_segs=%d\n", mmc->max_segs);
1316 	dev_dbg(mmc_dev(host->mmc), "max_blk_size=%d\n", mmc->max_blk_size);
1317 	dev_dbg(mmc_dev(host->mmc), "max_req_size=%d\n", mmc->max_req_size);
1318 	dev_dbg(mmc_dev(host->mmc), "max_seg_size=%d\n", mmc->max_seg_size);
1319 
1320 	platform_set_drvdata(pdev, host);
1321 
1322 	ret = mmc_davinci_cpufreq_register(host);
1323 	if (ret) {
1324 		dev_err(&pdev->dev, "failed to register cpufreq\n");
1325 		goto cpu_freq_fail;
1326 	}
1327 
1328 	ret = mmc_add_host(mmc);
1329 	if (ret < 0)
1330 		goto mmc_add_host_fail;
1331 
1332 	ret = devm_request_irq(&pdev->dev, irq, mmc_davinci_irq, 0,
1333 			       mmc_hostname(mmc), host);
1334 	if (ret)
1335 		goto request_irq_fail;
1336 
1337 	if (host->sdio_irq >= 0) {
1338 		ret = devm_request_irq(&pdev->dev, host->sdio_irq,
1339 				       mmc_davinci_sdio_irq, 0,
1340 				       mmc_hostname(mmc), host);
1341 		if (!ret)
1342 			mmc->caps |= MMC_CAP_SDIO_IRQ;
1343 	}
1344 
1345 	rename_region(mem, mmc_hostname(mmc));
1346 
1347 	dev_info(mmc_dev(host->mmc), "Using %s, %d-bit mode\n",
1348 		host->use_dma ? "DMA" : "PIO",
1349 		(mmc->caps & MMC_CAP_4_BIT_DATA) ? 4 : 1);
1350 
1351 	return 0;
1352 
1353 request_irq_fail:
1354 	mmc_remove_host(mmc);
1355 mmc_add_host_fail:
1356 	mmc_davinci_cpufreq_deregister(host);
1357 cpu_freq_fail:
1358 	davinci_release_dma_channels(host);
1359 parse_fail:
1360 dma_probe_defer:
1361 	clk_disable_unprepare(host->clk);
1362 clk_prepare_enable_fail:
1363 clk_get_fail:
1364 ioremap_fail:
1365 	mmc_free_host(mmc);
1366 
1367 	return ret;
1368 }
1369 
1370 static int __exit davinci_mmcsd_remove(struct platform_device *pdev)
1371 {
1372 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
1373 
1374 	mmc_remove_host(host->mmc);
1375 	mmc_davinci_cpufreq_deregister(host);
1376 	davinci_release_dma_channels(host);
1377 	clk_disable_unprepare(host->clk);
1378 	mmc_free_host(host->mmc);
1379 
1380 	return 0;
1381 }
1382 
1383 #ifdef CONFIG_PM
1384 static int davinci_mmcsd_suspend(struct device *dev)
1385 {
1386 	struct platform_device *pdev = to_platform_device(dev);
1387 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
1388 
1389 	writel(0, host->base + DAVINCI_MMCIM);
1390 	mmc_davinci_reset_ctrl(host, 1);
1391 	clk_disable(host->clk);
1392 
1393 	return 0;
1394 }
1395 
1396 static int davinci_mmcsd_resume(struct device *dev)
1397 {
1398 	struct platform_device *pdev = to_platform_device(dev);
1399 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
1400 
1401 	clk_enable(host->clk);
1402 	mmc_davinci_reset_ctrl(host, 0);
1403 
1404 	return 0;
1405 }
1406 
1407 static const struct dev_pm_ops davinci_mmcsd_pm = {
1408 	.suspend        = davinci_mmcsd_suspend,
1409 	.resume         = davinci_mmcsd_resume,
1410 };
1411 
1412 #define davinci_mmcsd_pm_ops (&davinci_mmcsd_pm)
1413 #else
1414 #define davinci_mmcsd_pm_ops NULL
1415 #endif
1416 
1417 static struct platform_driver davinci_mmcsd_driver = {
1418 	.driver		= {
1419 		.name	= "davinci_mmc",
1420 		.pm	= davinci_mmcsd_pm_ops,
1421 		.of_match_table = davinci_mmc_dt_ids,
1422 	},
1423 	.remove		= __exit_p(davinci_mmcsd_remove),
1424 	.id_table	= davinci_mmc_devtype,
1425 };
1426 
1427 module_platform_driver_probe(davinci_mmcsd_driver, davinci_mmcsd_probe);
1428 
1429 MODULE_AUTHOR("Texas Instruments India");
1430 MODULE_LICENSE("GPL");
1431 MODULE_DESCRIPTION("MMC/SD driver for Davinci MMC controller");
1432 MODULE_ALIAS("platform:davinci_mmc");
1433 
1434