xref: /openbmc/linux/drivers/mmc/host/davinci_mmc.c (revision bbb66fcb)
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/edma.h>
36 #include <linux/mmc/mmc.h>
37 #include <linux/of.h>
38 #include <linux/of_device.h>
39 
40 #include <linux/platform_data/edma.h>
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 	u32 rxdma, txdma;
206 	struct dma_chan *dma_tx;
207 	struct dma_chan *dma_rx;
208 	bool use_dma;
209 	bool do_dma;
210 	bool sdio_int;
211 	bool active_request;
212 
213 	/* For PIO we walk scatterlists one segment at a time. */
214 	unsigned int		sg_len;
215 	struct scatterlist *sg;
216 
217 	/* Version of the MMC/SD controller */
218 	u8 version;
219 	/* for ns in one cycle calculation */
220 	unsigned ns_in_one_cycle;
221 	/* Number of sg segments */
222 	u8 nr_sg;
223 #ifdef CONFIG_CPU_FREQ
224 	struct notifier_block	freq_transition;
225 #endif
226 };
227 
228 static irqreturn_t mmc_davinci_irq(int irq, void *dev_id);
229 
230 /* PIO only */
231 static void mmc_davinci_sg_to_buf(struct mmc_davinci_host *host)
232 {
233 	host->buffer_bytes_left = sg_dma_len(host->sg);
234 	host->buffer = sg_virt(host->sg);
235 	if (host->buffer_bytes_left > host->bytes_left)
236 		host->buffer_bytes_left = host->bytes_left;
237 }
238 
239 static void davinci_fifo_data_trans(struct mmc_davinci_host *host,
240 					unsigned int n)
241 {
242 	u8 *p;
243 	unsigned int i;
244 
245 	if (host->buffer_bytes_left == 0) {
246 		host->sg = sg_next(host->data->sg);
247 		mmc_davinci_sg_to_buf(host);
248 	}
249 
250 	p = host->buffer;
251 	if (n > host->buffer_bytes_left)
252 		n = host->buffer_bytes_left;
253 	host->buffer_bytes_left -= n;
254 	host->bytes_left -= n;
255 
256 	/* NOTE:  we never transfer more than rw_threshold bytes
257 	 * to/from the fifo here; there's no I/O overlap.
258 	 * This also assumes that access width( i.e. ACCWD) is 4 bytes
259 	 */
260 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE) {
261 		for (i = 0; i < (n >> 2); i++) {
262 			writel(*((u32 *)p), host->base + DAVINCI_MMCDXR);
263 			p = p + 4;
264 		}
265 		if (n & 3) {
266 			iowrite8_rep(host->base + DAVINCI_MMCDXR, p, (n & 3));
267 			p = p + (n & 3);
268 		}
269 	} else {
270 		for (i = 0; i < (n >> 2); i++) {
271 			*((u32 *)p) = readl(host->base + DAVINCI_MMCDRR);
272 			p  = p + 4;
273 		}
274 		if (n & 3) {
275 			ioread8_rep(host->base + DAVINCI_MMCDRR, p, (n & 3));
276 			p = p + (n & 3);
277 		}
278 	}
279 	host->buffer = p;
280 }
281 
282 static void mmc_davinci_start_command(struct mmc_davinci_host *host,
283 		struct mmc_command *cmd)
284 {
285 	u32 cmd_reg = 0;
286 	u32 im_val;
287 
288 	dev_dbg(mmc_dev(host->mmc), "CMD%d, arg 0x%08x%s\n",
289 		cmd->opcode, cmd->arg,
290 		({ char *s;
291 		switch (mmc_resp_type(cmd)) {
292 		case MMC_RSP_R1:
293 			s = ", R1/R5/R6/R7 response";
294 			break;
295 		case MMC_RSP_R1B:
296 			s = ", R1b response";
297 			break;
298 		case MMC_RSP_R2:
299 			s = ", R2 response";
300 			break;
301 		case MMC_RSP_R3:
302 			s = ", R3/R4 response";
303 			break;
304 		default:
305 			s = ", (R? response)";
306 			break;
307 		}; s; }));
308 	host->cmd = cmd;
309 
310 	switch (mmc_resp_type(cmd)) {
311 	case MMC_RSP_R1B:
312 		/* There's some spec confusion about when R1B is
313 		 * allowed, but if the card doesn't issue a BUSY
314 		 * then it's harmless for us to allow it.
315 		 */
316 		cmd_reg |= MMCCMD_BSYEXP;
317 		/* FALLTHROUGH */
318 	case MMC_RSP_R1:		/* 48 bits, CRC */
319 		cmd_reg |= MMCCMD_RSPFMT_R1456;
320 		break;
321 	case MMC_RSP_R2:		/* 136 bits, CRC */
322 		cmd_reg |= MMCCMD_RSPFMT_R2;
323 		break;
324 	case MMC_RSP_R3:		/* 48 bits, no CRC */
325 		cmd_reg |= MMCCMD_RSPFMT_R3;
326 		break;
327 	default:
328 		cmd_reg |= MMCCMD_RSPFMT_NONE;
329 		dev_dbg(mmc_dev(host->mmc), "unknown resp_type %04x\n",
330 			mmc_resp_type(cmd));
331 		break;
332 	}
333 
334 	/* Set command index */
335 	cmd_reg |= cmd->opcode;
336 
337 	/* Enable EDMA transfer triggers */
338 	if (host->do_dma)
339 		cmd_reg |= MMCCMD_DMATRIG;
340 
341 	if (host->version == MMC_CTLR_VERSION_2 && host->data != NULL &&
342 			host->data_dir == DAVINCI_MMC_DATADIR_READ)
343 		cmd_reg |= MMCCMD_DMATRIG;
344 
345 	/* Setting whether command involves data transfer or not */
346 	if (cmd->data)
347 		cmd_reg |= MMCCMD_WDATX;
348 
349 	/* Setting whether data read or write */
350 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE)
351 		cmd_reg |= MMCCMD_DTRW;
352 
353 	if (host->bus_mode == MMC_BUSMODE_PUSHPULL)
354 		cmd_reg |= MMCCMD_PPLEN;
355 
356 	/* set Command timeout */
357 	writel(0x1FFF, host->base + DAVINCI_MMCTOR);
358 
359 	/* Enable interrupt (calculate here, defer until FIFO is stuffed). */
360 	im_val =  MMCST0_RSPDNE | MMCST0_CRCRS | MMCST0_TOUTRS;
361 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE) {
362 		im_val |= MMCST0_DATDNE | MMCST0_CRCWR;
363 
364 		if (!host->do_dma)
365 			im_val |= MMCST0_DXRDY;
366 	} else if (host->data_dir == DAVINCI_MMC_DATADIR_READ) {
367 		im_val |= MMCST0_DATDNE | MMCST0_CRCRD | MMCST0_TOUTRD;
368 
369 		if (!host->do_dma)
370 			im_val |= MMCST0_DRRDY;
371 	}
372 
373 	/*
374 	 * Before non-DMA WRITE commands the controller needs priming:
375 	 * FIFO should be populated with 32 bytes i.e. whatever is the FIFO size
376 	 */
377 	if (!host->do_dma && (host->data_dir == DAVINCI_MMC_DATADIR_WRITE))
378 		davinci_fifo_data_trans(host, rw_threshold);
379 
380 	writel(cmd->arg, host->base + DAVINCI_MMCARGHL);
381 	writel(cmd_reg,  host->base + DAVINCI_MMCCMD);
382 
383 	host->active_request = true;
384 
385 	if (!host->do_dma && host->bytes_left <= poll_threshold) {
386 		u32 count = poll_loopcount;
387 
388 		while (host->active_request && count--) {
389 			mmc_davinci_irq(0, host);
390 			cpu_relax();
391 		}
392 	}
393 
394 	if (host->active_request)
395 		writel(im_val, host->base + DAVINCI_MMCIM);
396 }
397 
398 /*----------------------------------------------------------------------*/
399 
400 /* DMA infrastructure */
401 
402 static void davinci_abort_dma(struct mmc_davinci_host *host)
403 {
404 	struct dma_chan *sync_dev;
405 
406 	if (host->data_dir == DAVINCI_MMC_DATADIR_READ)
407 		sync_dev = host->dma_rx;
408 	else
409 		sync_dev = host->dma_tx;
410 
411 	dmaengine_terminate_all(sync_dev);
412 }
413 
414 static int mmc_davinci_send_dma_request(struct mmc_davinci_host *host,
415 		struct mmc_data *data)
416 {
417 	struct dma_chan *chan;
418 	struct dma_async_tx_descriptor *desc;
419 	int ret = 0;
420 
421 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE) {
422 		struct dma_slave_config dma_tx_conf = {
423 			.direction = DMA_MEM_TO_DEV,
424 			.dst_addr = host->mem_res->start + DAVINCI_MMCDXR,
425 			.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
426 			.dst_maxburst =
427 				rw_threshold / DMA_SLAVE_BUSWIDTH_4_BYTES,
428 		};
429 		chan = host->dma_tx;
430 		dmaengine_slave_config(host->dma_tx, &dma_tx_conf);
431 
432 		desc = dmaengine_prep_slave_sg(host->dma_tx,
433 				data->sg,
434 				host->sg_len,
435 				DMA_MEM_TO_DEV,
436 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
437 		if (!desc) {
438 			dev_dbg(mmc_dev(host->mmc),
439 				"failed to allocate DMA TX descriptor");
440 			ret = -1;
441 			goto out;
442 		}
443 	} else {
444 		struct dma_slave_config dma_rx_conf = {
445 			.direction = DMA_DEV_TO_MEM,
446 			.src_addr = host->mem_res->start + DAVINCI_MMCDRR,
447 			.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
448 			.src_maxburst =
449 				rw_threshold / DMA_SLAVE_BUSWIDTH_4_BYTES,
450 		};
451 		chan = host->dma_rx;
452 		dmaengine_slave_config(host->dma_rx, &dma_rx_conf);
453 
454 		desc = dmaengine_prep_slave_sg(host->dma_rx,
455 				data->sg,
456 				host->sg_len,
457 				DMA_DEV_TO_MEM,
458 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
459 		if (!desc) {
460 			dev_dbg(mmc_dev(host->mmc),
461 				"failed to allocate DMA RX descriptor");
462 			ret = -1;
463 			goto out;
464 		}
465 	}
466 
467 	dmaengine_submit(desc);
468 	dma_async_issue_pending(chan);
469 
470 out:
471 	return ret;
472 }
473 
474 static int mmc_davinci_start_dma_transfer(struct mmc_davinci_host *host,
475 		struct mmc_data *data)
476 {
477 	int i;
478 	int mask = rw_threshold - 1;
479 	int ret = 0;
480 
481 	host->sg_len = dma_map_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
482 				((data->flags & MMC_DATA_WRITE)
483 				? DMA_TO_DEVICE
484 				: DMA_FROM_DEVICE));
485 
486 	/* no individual DMA segment should need a partial FIFO */
487 	for (i = 0; i < host->sg_len; i++) {
488 		if (sg_dma_len(data->sg + i) & mask) {
489 			dma_unmap_sg(mmc_dev(host->mmc),
490 					data->sg, data->sg_len,
491 					(data->flags & MMC_DATA_WRITE)
492 					? DMA_TO_DEVICE
493 					: DMA_FROM_DEVICE);
494 			return -1;
495 		}
496 	}
497 
498 	host->do_dma = 1;
499 	ret = mmc_davinci_send_dma_request(host, data);
500 
501 	return ret;
502 }
503 
504 static void __init_or_module
505 davinci_release_dma_channels(struct mmc_davinci_host *host)
506 {
507 	if (!host->use_dma)
508 		return;
509 
510 	dma_release_channel(host->dma_tx);
511 	dma_release_channel(host->dma_rx);
512 }
513 
514 static int __init davinci_acquire_dma_channels(struct mmc_davinci_host *host)
515 {
516 	int r;
517 	dma_cap_mask_t mask;
518 
519 	dma_cap_zero(mask);
520 	dma_cap_set(DMA_SLAVE, mask);
521 
522 	host->dma_tx =
523 		dma_request_slave_channel_compat(mask, edma_filter_fn,
524 				&host->txdma, mmc_dev(host->mmc), "tx");
525 	if (!host->dma_tx) {
526 		dev_err(mmc_dev(host->mmc), "Can't get dma_tx channel\n");
527 		return -ENODEV;
528 	}
529 
530 	host->dma_rx =
531 		dma_request_slave_channel_compat(mask, edma_filter_fn,
532 				&host->rxdma, mmc_dev(host->mmc), "rx");
533 	if (!host->dma_rx) {
534 		dev_err(mmc_dev(host->mmc), "Can't get dma_rx channel\n");
535 		r = -ENODEV;
536 		goto free_master_write;
537 	}
538 
539 	return 0;
540 
541 free_master_write:
542 	dma_release_channel(host->dma_tx);
543 
544 	return r;
545 }
546 
547 /*----------------------------------------------------------------------*/
548 
549 static void
550 mmc_davinci_prepare_data(struct mmc_davinci_host *host, struct mmc_request *req)
551 {
552 	int fifo_lev = (rw_threshold == 32) ? MMCFIFOCTL_FIFOLEV : 0;
553 	int timeout;
554 	struct mmc_data *data = req->data;
555 
556 	if (host->version == MMC_CTLR_VERSION_2)
557 		fifo_lev = (rw_threshold == 64) ? MMCFIFOCTL_FIFOLEV : 0;
558 
559 	host->data = data;
560 	if (data == NULL) {
561 		host->data_dir = DAVINCI_MMC_DATADIR_NONE;
562 		writel(0, host->base + DAVINCI_MMCBLEN);
563 		writel(0, host->base + DAVINCI_MMCNBLK);
564 		return;
565 	}
566 
567 	dev_dbg(mmc_dev(host->mmc), "%s, %d blocks of %d bytes\n",
568 		(data->flags & MMC_DATA_WRITE) ? "write" : "read",
569 		data->blocks, data->blksz);
570 	dev_dbg(mmc_dev(host->mmc), "  DTO %d cycles + %d ns\n",
571 		data->timeout_clks, data->timeout_ns);
572 	timeout = data->timeout_clks +
573 		(data->timeout_ns / host->ns_in_one_cycle);
574 	if (timeout > 0xffff)
575 		timeout = 0xffff;
576 
577 	writel(timeout, host->base + DAVINCI_MMCTOD);
578 	writel(data->blocks, host->base + DAVINCI_MMCNBLK);
579 	writel(data->blksz, host->base + DAVINCI_MMCBLEN);
580 
581 	/* Configure the FIFO */
582 	if (data->flags & MMC_DATA_WRITE) {
583 		host->data_dir = DAVINCI_MMC_DATADIR_WRITE;
584 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_WR | MMCFIFOCTL_FIFORST,
585 			host->base + DAVINCI_MMCFIFOCTL);
586 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_WR,
587 			host->base + DAVINCI_MMCFIFOCTL);
588 	} else {
589 		host->data_dir = DAVINCI_MMC_DATADIR_READ;
590 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_RD | MMCFIFOCTL_FIFORST,
591 			host->base + DAVINCI_MMCFIFOCTL);
592 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_RD,
593 			host->base + DAVINCI_MMCFIFOCTL);
594 	}
595 
596 	host->buffer = NULL;
597 	host->bytes_left = data->blocks * data->blksz;
598 
599 	/* For now we try to use DMA whenever we won't need partial FIFO
600 	 * reads or writes, either for the whole transfer (as tested here)
601 	 * or for any individual scatterlist segment (tested when we call
602 	 * start_dma_transfer).
603 	 *
604 	 * While we *could* change that, unusual block sizes are rarely
605 	 * used.  The occasional fallback to PIO should't hurt.
606 	 */
607 	if (host->use_dma && (host->bytes_left & (rw_threshold - 1)) == 0
608 			&& mmc_davinci_start_dma_transfer(host, data) == 0) {
609 		/* zero this to ensure we take no PIO paths */
610 		host->bytes_left = 0;
611 	} else {
612 		/* Revert to CPU Copy */
613 		host->sg_len = data->sg_len;
614 		host->sg = host->data->sg;
615 		mmc_davinci_sg_to_buf(host);
616 	}
617 }
618 
619 static void mmc_davinci_request(struct mmc_host *mmc, struct mmc_request *req)
620 {
621 	struct mmc_davinci_host *host = mmc_priv(mmc);
622 	unsigned long timeout = jiffies + msecs_to_jiffies(900);
623 	u32 mmcst1 = 0;
624 
625 	/* Card may still be sending BUSY after a previous operation,
626 	 * typically some kind of write.  If so, we can't proceed yet.
627 	 */
628 	while (time_before(jiffies, timeout)) {
629 		mmcst1  = readl(host->base + DAVINCI_MMCST1);
630 		if (!(mmcst1 & MMCST1_BUSY))
631 			break;
632 		cpu_relax();
633 	}
634 	if (mmcst1 & MMCST1_BUSY) {
635 		dev_err(mmc_dev(host->mmc), "still BUSY? bad ... \n");
636 		req->cmd->error = -ETIMEDOUT;
637 		mmc_request_done(mmc, req);
638 		return;
639 	}
640 
641 	host->do_dma = 0;
642 	mmc_davinci_prepare_data(host, req);
643 	mmc_davinci_start_command(host, req->cmd);
644 }
645 
646 static unsigned int calculate_freq_for_card(struct mmc_davinci_host *host,
647 	unsigned int mmc_req_freq)
648 {
649 	unsigned int mmc_freq = 0, mmc_pclk = 0, mmc_push_pull_divisor = 0;
650 
651 	mmc_pclk = host->mmc_input_clk;
652 	if (mmc_req_freq && mmc_pclk > (2 * mmc_req_freq))
653 		mmc_push_pull_divisor = ((unsigned int)mmc_pclk
654 				/ (2 * mmc_req_freq)) - 1;
655 	else
656 		mmc_push_pull_divisor = 0;
657 
658 	mmc_freq = (unsigned int)mmc_pclk
659 		/ (2 * (mmc_push_pull_divisor + 1));
660 
661 	if (mmc_freq > mmc_req_freq)
662 		mmc_push_pull_divisor = mmc_push_pull_divisor + 1;
663 	/* Convert ns to clock cycles */
664 	if (mmc_req_freq <= 400000)
665 		host->ns_in_one_cycle = (1000000) / (((mmc_pclk
666 				/ (2 * (mmc_push_pull_divisor + 1)))/1000));
667 	else
668 		host->ns_in_one_cycle = (1000000) / (((mmc_pclk
669 				/ (2 * (mmc_push_pull_divisor + 1)))/1000000));
670 
671 	return mmc_push_pull_divisor;
672 }
673 
674 static void calculate_clk_divider(struct mmc_host *mmc, struct mmc_ios *ios)
675 {
676 	unsigned int open_drain_freq = 0, mmc_pclk = 0;
677 	unsigned int mmc_push_pull_freq = 0;
678 	struct mmc_davinci_host *host = mmc_priv(mmc);
679 
680 	if (ios->bus_mode == MMC_BUSMODE_OPENDRAIN) {
681 		u32 temp;
682 
683 		/* Ignoring the init clock value passed for fixing the inter
684 		 * operability with different cards.
685 		 */
686 		open_drain_freq = ((unsigned int)mmc_pclk
687 				/ (2 * MMCSD_INIT_CLOCK)) - 1;
688 
689 		if (open_drain_freq > 0xFF)
690 			open_drain_freq = 0xFF;
691 
692 		temp = readl(host->base + DAVINCI_MMCCLK) & ~MMCCLK_CLKRT_MASK;
693 		temp |= open_drain_freq;
694 		writel(temp, host->base + DAVINCI_MMCCLK);
695 
696 		/* Convert ns to clock cycles */
697 		host->ns_in_one_cycle = (1000000) / (MMCSD_INIT_CLOCK/1000);
698 	} else {
699 		u32 temp;
700 		mmc_push_pull_freq = calculate_freq_for_card(host, ios->clock);
701 
702 		if (mmc_push_pull_freq > 0xFF)
703 			mmc_push_pull_freq = 0xFF;
704 
705 		temp = readl(host->base + DAVINCI_MMCCLK) & ~MMCCLK_CLKEN;
706 		writel(temp, host->base + DAVINCI_MMCCLK);
707 
708 		udelay(10);
709 
710 		temp = readl(host->base + DAVINCI_MMCCLK) & ~MMCCLK_CLKRT_MASK;
711 		temp |= mmc_push_pull_freq;
712 		writel(temp, host->base + DAVINCI_MMCCLK);
713 
714 		writel(temp | MMCCLK_CLKEN, host->base + DAVINCI_MMCCLK);
715 
716 		udelay(10);
717 	}
718 }
719 
720 static void mmc_davinci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
721 {
722 	struct mmc_davinci_host *host = mmc_priv(mmc);
723 	struct platform_device *pdev = to_platform_device(mmc->parent);
724 	struct davinci_mmc_config *config = pdev->dev.platform_data;
725 
726 	dev_dbg(mmc_dev(host->mmc),
727 		"clock %dHz busmode %d powermode %d Vdd %04x\n",
728 		ios->clock, ios->bus_mode, ios->power_mode,
729 		ios->vdd);
730 
731 	switch (ios->power_mode) {
732 	case MMC_POWER_OFF:
733 		if (config && config->set_power)
734 			config->set_power(pdev->id, false);
735 		break;
736 	case MMC_POWER_UP:
737 		if (config && config->set_power)
738 			config->set_power(pdev->id, true);
739 		break;
740 	}
741 
742 	switch (ios->bus_width) {
743 	case MMC_BUS_WIDTH_8:
744 		dev_dbg(mmc_dev(host->mmc), "Enabling 8 bit mode\n");
745 		writel((readl(host->base + DAVINCI_MMCCTL) &
746 			~MMCCTL_WIDTH_4_BIT) | MMCCTL_WIDTH_8_BIT,
747 			host->base + DAVINCI_MMCCTL);
748 		break;
749 	case MMC_BUS_WIDTH_4:
750 		dev_dbg(mmc_dev(host->mmc), "Enabling 4 bit mode\n");
751 		if (host->version == MMC_CTLR_VERSION_2)
752 			writel((readl(host->base + DAVINCI_MMCCTL) &
753 				~MMCCTL_WIDTH_8_BIT) | MMCCTL_WIDTH_4_BIT,
754 				host->base + DAVINCI_MMCCTL);
755 		else
756 			writel(readl(host->base + DAVINCI_MMCCTL) |
757 				MMCCTL_WIDTH_4_BIT,
758 				host->base + DAVINCI_MMCCTL);
759 		break;
760 	case MMC_BUS_WIDTH_1:
761 		dev_dbg(mmc_dev(host->mmc), "Enabling 1 bit mode\n");
762 		if (host->version == MMC_CTLR_VERSION_2)
763 			writel(readl(host->base + DAVINCI_MMCCTL) &
764 				~(MMCCTL_WIDTH_8_BIT | MMCCTL_WIDTH_4_BIT),
765 				host->base + DAVINCI_MMCCTL);
766 		else
767 			writel(readl(host->base + DAVINCI_MMCCTL) &
768 				~MMCCTL_WIDTH_4_BIT,
769 				host->base + DAVINCI_MMCCTL);
770 		break;
771 	}
772 
773 	calculate_clk_divider(mmc, ios);
774 
775 	host->bus_mode = ios->bus_mode;
776 	if (ios->power_mode == MMC_POWER_UP) {
777 		unsigned long timeout = jiffies + msecs_to_jiffies(50);
778 		bool lose = true;
779 
780 		/* Send clock cycles, poll completion */
781 		writel(0, host->base + DAVINCI_MMCARGHL);
782 		writel(MMCCMD_INITCK, host->base + DAVINCI_MMCCMD);
783 		while (time_before(jiffies, timeout)) {
784 			u32 tmp = readl(host->base + DAVINCI_MMCST0);
785 
786 			if (tmp & MMCST0_RSPDNE) {
787 				lose = false;
788 				break;
789 			}
790 			cpu_relax();
791 		}
792 		if (lose)
793 			dev_warn(mmc_dev(host->mmc), "powerup timeout\n");
794 	}
795 
796 	/* FIXME on power OFF, reset things ... */
797 }
798 
799 static void
800 mmc_davinci_xfer_done(struct mmc_davinci_host *host, struct mmc_data *data)
801 {
802 	host->data = NULL;
803 
804 	if (host->mmc->caps & MMC_CAP_SDIO_IRQ) {
805 		/*
806 		 * SDIO Interrupt Detection work-around as suggested by
807 		 * Davinci Errata (TMS320DM355 Silicon Revision 1.1 Errata
808 		 * 2.1.6): Signal SDIO interrupt only if it is enabled by core
809 		 */
810 		if (host->sdio_int && !(readl(host->base + DAVINCI_SDIOST0) &
811 					SDIOST0_DAT1_HI)) {
812 			writel(SDIOIST_IOINT, host->base + DAVINCI_SDIOIST);
813 			mmc_signal_sdio_irq(host->mmc);
814 		}
815 	}
816 
817 	if (host->do_dma) {
818 		davinci_abort_dma(host);
819 
820 		dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
821 			     (data->flags & MMC_DATA_WRITE)
822 			     ? DMA_TO_DEVICE
823 			     : DMA_FROM_DEVICE);
824 		host->do_dma = false;
825 	}
826 	host->data_dir = DAVINCI_MMC_DATADIR_NONE;
827 
828 	if (!data->stop || (host->cmd && host->cmd->error)) {
829 		mmc_request_done(host->mmc, data->mrq);
830 		writel(0, host->base + DAVINCI_MMCIM);
831 		host->active_request = false;
832 	} else
833 		mmc_davinci_start_command(host, data->stop);
834 }
835 
836 static void mmc_davinci_cmd_done(struct mmc_davinci_host *host,
837 				 struct mmc_command *cmd)
838 {
839 	host->cmd = NULL;
840 
841 	if (cmd->flags & MMC_RSP_PRESENT) {
842 		if (cmd->flags & MMC_RSP_136) {
843 			/* response type 2 */
844 			cmd->resp[3] = readl(host->base + DAVINCI_MMCRSP01);
845 			cmd->resp[2] = readl(host->base + DAVINCI_MMCRSP23);
846 			cmd->resp[1] = readl(host->base + DAVINCI_MMCRSP45);
847 			cmd->resp[0] = readl(host->base + DAVINCI_MMCRSP67);
848 		} else {
849 			/* response types 1, 1b, 3, 4, 5, 6 */
850 			cmd->resp[0] = readl(host->base + DAVINCI_MMCRSP67);
851 		}
852 	}
853 
854 	if (host->data == NULL || cmd->error) {
855 		if (cmd->error == -ETIMEDOUT)
856 			cmd->mrq->cmd->retries = 0;
857 		mmc_request_done(host->mmc, cmd->mrq);
858 		writel(0, host->base + DAVINCI_MMCIM);
859 		host->active_request = false;
860 	}
861 }
862 
863 static inline void mmc_davinci_reset_ctrl(struct mmc_davinci_host *host,
864 								int val)
865 {
866 	u32 temp;
867 
868 	temp = readl(host->base + DAVINCI_MMCCTL);
869 	if (val)	/* reset */
870 		temp |= MMCCTL_CMDRST | MMCCTL_DATRST;
871 	else		/* enable */
872 		temp &= ~(MMCCTL_CMDRST | MMCCTL_DATRST);
873 
874 	writel(temp, host->base + DAVINCI_MMCCTL);
875 	udelay(10);
876 }
877 
878 static void
879 davinci_abort_data(struct mmc_davinci_host *host, struct mmc_data *data)
880 {
881 	mmc_davinci_reset_ctrl(host, 1);
882 	mmc_davinci_reset_ctrl(host, 0);
883 }
884 
885 static irqreturn_t mmc_davinci_sdio_irq(int irq, void *dev_id)
886 {
887 	struct mmc_davinci_host *host = dev_id;
888 	unsigned int status;
889 
890 	status = readl(host->base + DAVINCI_SDIOIST);
891 	if (status & SDIOIST_IOINT) {
892 		dev_dbg(mmc_dev(host->mmc),
893 			"SDIO interrupt status %x\n", status);
894 		writel(status | SDIOIST_IOINT, host->base + DAVINCI_SDIOIST);
895 		mmc_signal_sdio_irq(host->mmc);
896 	}
897 	return IRQ_HANDLED;
898 }
899 
900 static irqreturn_t mmc_davinci_irq(int irq, void *dev_id)
901 {
902 	struct mmc_davinci_host *host = (struct mmc_davinci_host *)dev_id;
903 	unsigned int status, qstatus;
904 	int end_command = 0;
905 	int end_transfer = 0;
906 	struct mmc_data *data = host->data;
907 
908 	if (host->cmd == NULL && host->data == NULL) {
909 		status = readl(host->base + DAVINCI_MMCST0);
910 		dev_dbg(mmc_dev(host->mmc),
911 			"Spurious interrupt 0x%04x\n", status);
912 		/* Disable the interrupt from mmcsd */
913 		writel(0, host->base + DAVINCI_MMCIM);
914 		return IRQ_NONE;
915 	}
916 
917 	status = readl(host->base + DAVINCI_MMCST0);
918 	qstatus = status;
919 
920 	/* handle FIFO first when using PIO for data.
921 	 * bytes_left will decrease to zero as I/O progress and status will
922 	 * read zero over iteration because this controller status
923 	 * register(MMCST0) reports any status only once and it is cleared
924 	 * by read. So, it is not unbouned loop even in the case of
925 	 * non-dma.
926 	 */
927 	if (host->bytes_left && (status & (MMCST0_DXRDY | MMCST0_DRRDY))) {
928 		unsigned long im_val;
929 
930 		/*
931 		 * If interrupts fire during the following loop, they will be
932 		 * handled by the handler, but the PIC will still buffer these.
933 		 * As a result, the handler will be called again to serve these
934 		 * needlessly. In order to avoid these spurious interrupts,
935 		 * keep interrupts masked during the loop.
936 		 */
937 		im_val = readl(host->base + DAVINCI_MMCIM);
938 		writel(0, host->base + DAVINCI_MMCIM);
939 
940 		do {
941 			davinci_fifo_data_trans(host, rw_threshold);
942 			status = readl(host->base + DAVINCI_MMCST0);
943 			qstatus |= status;
944 		} while (host->bytes_left &&
945 			 (status & (MMCST0_DXRDY | MMCST0_DRRDY)));
946 
947 		/*
948 		 * If an interrupt is pending, it is assumed it will fire when
949 		 * it is unmasked. This assumption is also taken when the MMCIM
950 		 * is first set. Otherwise, writing to MMCIM after reading the
951 		 * status is race-prone.
952 		 */
953 		writel(im_val, host->base + DAVINCI_MMCIM);
954 	}
955 
956 	if (qstatus & MMCST0_DATDNE) {
957 		/* All blocks sent/received, and CRC checks passed */
958 		if (data != NULL) {
959 			if ((host->do_dma == 0) && (host->bytes_left > 0)) {
960 				/* if datasize < rw_threshold
961 				 * no RX ints are generated
962 				 */
963 				davinci_fifo_data_trans(host, host->bytes_left);
964 			}
965 			end_transfer = 1;
966 			data->bytes_xfered = data->blocks * data->blksz;
967 		} else {
968 			dev_err(mmc_dev(host->mmc),
969 					"DATDNE with no host->data\n");
970 		}
971 	}
972 
973 	if (qstatus & MMCST0_TOUTRD) {
974 		/* Read data timeout */
975 		data->error = -ETIMEDOUT;
976 		end_transfer = 1;
977 
978 		dev_dbg(mmc_dev(host->mmc),
979 			"read data timeout, status %x\n",
980 			qstatus);
981 
982 		davinci_abort_data(host, data);
983 	}
984 
985 	if (qstatus & (MMCST0_CRCWR | MMCST0_CRCRD)) {
986 		/* Data CRC error */
987 		data->error = -EILSEQ;
988 		end_transfer = 1;
989 
990 		/* NOTE:  this controller uses CRCWR to report both CRC
991 		 * errors and timeouts (on writes).  MMCDRSP values are
992 		 * only weakly documented, but 0x9f was clearly a timeout
993 		 * case and the two three-bit patterns in various SD specs
994 		 * (101, 010) aren't part of it ...
995 		 */
996 		if (qstatus & MMCST0_CRCWR) {
997 			u32 temp = readb(host->base + DAVINCI_MMCDRSP);
998 
999 			if (temp == 0x9f)
1000 				data->error = -ETIMEDOUT;
1001 		}
1002 		dev_dbg(mmc_dev(host->mmc), "data %s %s error\n",
1003 			(qstatus & MMCST0_CRCWR) ? "write" : "read",
1004 			(data->error == -ETIMEDOUT) ? "timeout" : "CRC");
1005 
1006 		davinci_abort_data(host, data);
1007 	}
1008 
1009 	if (qstatus & MMCST0_TOUTRS) {
1010 		/* Command timeout */
1011 		if (host->cmd) {
1012 			dev_dbg(mmc_dev(host->mmc),
1013 				"CMD%d timeout, status %x\n",
1014 				host->cmd->opcode, qstatus);
1015 			host->cmd->error = -ETIMEDOUT;
1016 			if (data) {
1017 				end_transfer = 1;
1018 				davinci_abort_data(host, data);
1019 			} else
1020 				end_command = 1;
1021 		}
1022 	}
1023 
1024 	if (qstatus & MMCST0_CRCRS) {
1025 		/* Command CRC error */
1026 		dev_dbg(mmc_dev(host->mmc), "Command CRC error\n");
1027 		if (host->cmd) {
1028 			host->cmd->error = -EILSEQ;
1029 			end_command = 1;
1030 		}
1031 	}
1032 
1033 	if (qstatus & MMCST0_RSPDNE) {
1034 		/* End of command phase */
1035 		end_command = (int) host->cmd;
1036 	}
1037 
1038 	if (end_command)
1039 		mmc_davinci_cmd_done(host, host->cmd);
1040 	if (end_transfer)
1041 		mmc_davinci_xfer_done(host, data);
1042 	return IRQ_HANDLED;
1043 }
1044 
1045 static int mmc_davinci_get_cd(struct mmc_host *mmc)
1046 {
1047 	struct platform_device *pdev = to_platform_device(mmc->parent);
1048 	struct davinci_mmc_config *config = pdev->dev.platform_data;
1049 
1050 	if (!config || !config->get_cd)
1051 		return -ENOSYS;
1052 	return config->get_cd(pdev->id);
1053 }
1054 
1055 static int mmc_davinci_get_ro(struct mmc_host *mmc)
1056 {
1057 	struct platform_device *pdev = to_platform_device(mmc->parent);
1058 	struct davinci_mmc_config *config = pdev->dev.platform_data;
1059 
1060 	if (!config || !config->get_ro)
1061 		return -ENOSYS;
1062 	return config->get_ro(pdev->id);
1063 }
1064 
1065 static void mmc_davinci_enable_sdio_irq(struct mmc_host *mmc, int enable)
1066 {
1067 	struct mmc_davinci_host *host = mmc_priv(mmc);
1068 
1069 	if (enable) {
1070 		if (!(readl(host->base + DAVINCI_SDIOST0) & SDIOST0_DAT1_HI)) {
1071 			writel(SDIOIST_IOINT, host->base + DAVINCI_SDIOIST);
1072 			mmc_signal_sdio_irq(host->mmc);
1073 		} else {
1074 			host->sdio_int = true;
1075 			writel(readl(host->base + DAVINCI_SDIOIEN) |
1076 			       SDIOIEN_IOINTEN, host->base + DAVINCI_SDIOIEN);
1077 		}
1078 	} else {
1079 		host->sdio_int = false;
1080 		writel(readl(host->base + DAVINCI_SDIOIEN) & ~SDIOIEN_IOINTEN,
1081 		       host->base + DAVINCI_SDIOIEN);
1082 	}
1083 }
1084 
1085 static struct mmc_host_ops mmc_davinci_ops = {
1086 	.request	= mmc_davinci_request,
1087 	.set_ios	= mmc_davinci_set_ios,
1088 	.get_cd		= mmc_davinci_get_cd,
1089 	.get_ro		= mmc_davinci_get_ro,
1090 	.enable_sdio_irq = mmc_davinci_enable_sdio_irq,
1091 };
1092 
1093 /*----------------------------------------------------------------------*/
1094 
1095 #ifdef CONFIG_CPU_FREQ
1096 static int mmc_davinci_cpufreq_transition(struct notifier_block *nb,
1097 				     unsigned long val, void *data)
1098 {
1099 	struct mmc_davinci_host *host;
1100 	unsigned int mmc_pclk;
1101 	struct mmc_host *mmc;
1102 	unsigned long flags;
1103 
1104 	host = container_of(nb, struct mmc_davinci_host, freq_transition);
1105 	mmc = host->mmc;
1106 	mmc_pclk = clk_get_rate(host->clk);
1107 
1108 	if (val == CPUFREQ_POSTCHANGE) {
1109 		spin_lock_irqsave(&mmc->lock, flags);
1110 		host->mmc_input_clk = mmc_pclk;
1111 		calculate_clk_divider(mmc, &mmc->ios);
1112 		spin_unlock_irqrestore(&mmc->lock, flags);
1113 	}
1114 
1115 	return 0;
1116 }
1117 
1118 static inline int mmc_davinci_cpufreq_register(struct mmc_davinci_host *host)
1119 {
1120 	host->freq_transition.notifier_call = mmc_davinci_cpufreq_transition;
1121 
1122 	return cpufreq_register_notifier(&host->freq_transition,
1123 					 CPUFREQ_TRANSITION_NOTIFIER);
1124 }
1125 
1126 static inline void mmc_davinci_cpufreq_deregister(struct mmc_davinci_host *host)
1127 {
1128 	cpufreq_unregister_notifier(&host->freq_transition,
1129 				    CPUFREQ_TRANSITION_NOTIFIER);
1130 }
1131 #else
1132 static inline int mmc_davinci_cpufreq_register(struct mmc_davinci_host *host)
1133 {
1134 	return 0;
1135 }
1136 
1137 static inline void mmc_davinci_cpufreq_deregister(struct mmc_davinci_host *host)
1138 {
1139 }
1140 #endif
1141 static void __init init_mmcsd_host(struct mmc_davinci_host *host)
1142 {
1143 
1144 	mmc_davinci_reset_ctrl(host, 1);
1145 
1146 	writel(0, host->base + DAVINCI_MMCCLK);
1147 	writel(MMCCLK_CLKEN, host->base + DAVINCI_MMCCLK);
1148 
1149 	writel(0x1FFF, host->base + DAVINCI_MMCTOR);
1150 	writel(0xFFFF, host->base + DAVINCI_MMCTOD);
1151 
1152 	mmc_davinci_reset_ctrl(host, 0);
1153 }
1154 
1155 static const struct platform_device_id davinci_mmc_devtype[] = {
1156 	{
1157 		.name	= "dm6441-mmc",
1158 		.driver_data = MMC_CTLR_VERSION_1,
1159 	}, {
1160 		.name	= "da830-mmc",
1161 		.driver_data = MMC_CTLR_VERSION_2,
1162 	},
1163 	{},
1164 };
1165 MODULE_DEVICE_TABLE(platform, davinci_mmc_devtype);
1166 
1167 static const struct of_device_id davinci_mmc_dt_ids[] = {
1168 	{
1169 		.compatible = "ti,dm6441-mmc",
1170 		.data = &davinci_mmc_devtype[MMC_CTLR_VERSION_1],
1171 	},
1172 	{
1173 		.compatible = "ti,da830-mmc",
1174 		.data = &davinci_mmc_devtype[MMC_CTLR_VERSION_2],
1175 	},
1176 	{},
1177 };
1178 MODULE_DEVICE_TABLE(of, davinci_mmc_dt_ids);
1179 
1180 static struct davinci_mmc_config
1181 	*mmc_parse_pdata(struct platform_device *pdev)
1182 {
1183 	struct device_node *np;
1184 	struct davinci_mmc_config *pdata = pdev->dev.platform_data;
1185 	const struct of_device_id *match =
1186 		of_match_device(davinci_mmc_dt_ids, &pdev->dev);
1187 	u32 data;
1188 
1189 	np = pdev->dev.of_node;
1190 	if (!np)
1191 		return pdata;
1192 
1193 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
1194 	if (!pdata) {
1195 		dev_err(&pdev->dev, "Failed to allocate memory for struct davinci_mmc_config\n");
1196 		goto nodata;
1197 	}
1198 
1199 	if (match)
1200 		pdev->id_entry = match->data;
1201 
1202 	if (of_property_read_u32(np, "max-frequency", &pdata->max_freq))
1203 		dev_info(&pdev->dev, "'max-frequency' property not specified, defaulting to 25MHz\n");
1204 
1205 	of_property_read_u32(np, "bus-width", &data);
1206 	switch (data) {
1207 	case 1:
1208 	case 4:
1209 	case 8:
1210 		pdata->wires = data;
1211 		break;
1212 	default:
1213 		pdata->wires = 1;
1214 		dev_info(&pdev->dev, "Unsupported buswidth, defaulting to 1 bit\n");
1215 	}
1216 nodata:
1217 	return pdata;
1218 }
1219 
1220 static int __init davinci_mmcsd_probe(struct platform_device *pdev)
1221 {
1222 	struct davinci_mmc_config *pdata = NULL;
1223 	struct mmc_davinci_host *host = NULL;
1224 	struct mmc_host *mmc = NULL;
1225 	struct resource *r, *mem = NULL;
1226 	int ret = 0, irq = 0;
1227 	size_t mem_size;
1228 	const struct platform_device_id *id_entry;
1229 
1230 	pdata = mmc_parse_pdata(pdev);
1231 	if (pdata == NULL) {
1232 		dev_err(&pdev->dev, "Couldn't get platform data\n");
1233 		return -ENOENT;
1234 	}
1235 
1236 	ret = -ENODEV;
1237 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1238 	irq = platform_get_irq(pdev, 0);
1239 	if (!r || irq == NO_IRQ)
1240 		goto out;
1241 
1242 	ret = -EBUSY;
1243 	mem_size = resource_size(r);
1244 	mem = request_mem_region(r->start, mem_size, pdev->name);
1245 	if (!mem)
1246 		goto out;
1247 
1248 	ret = -ENOMEM;
1249 	mmc = mmc_alloc_host(sizeof(struct mmc_davinci_host), &pdev->dev);
1250 	if (!mmc)
1251 		goto out;
1252 
1253 	host = mmc_priv(mmc);
1254 	host->mmc = mmc;	/* Important */
1255 
1256 	r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1257 	if (!r)
1258 		dev_warn(&pdev->dev, "RX DMA resource not specified\n");
1259 	else
1260 		host->rxdma = r->start;
1261 
1262 	r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
1263 	if (!r)
1264 		dev_warn(&pdev->dev, "TX DMA resource not specified\n");
1265 	else
1266 		host->txdma = r->start;
1267 
1268 	host->mem_res = mem;
1269 	host->base = ioremap(mem->start, mem_size);
1270 	if (!host->base)
1271 		goto out;
1272 
1273 	ret = -ENXIO;
1274 	host->clk = clk_get(&pdev->dev, "MMCSDCLK");
1275 	if (IS_ERR(host->clk)) {
1276 		ret = PTR_ERR(host->clk);
1277 		goto out;
1278 	}
1279 	clk_enable(host->clk);
1280 	host->mmc_input_clk = clk_get_rate(host->clk);
1281 
1282 	init_mmcsd_host(host);
1283 
1284 	if (pdata->nr_sg)
1285 		host->nr_sg = pdata->nr_sg - 1;
1286 
1287 	if (host->nr_sg > MAX_NR_SG || !host->nr_sg)
1288 		host->nr_sg = MAX_NR_SG;
1289 
1290 	host->use_dma = use_dma;
1291 	host->mmc_irq = irq;
1292 	host->sdio_irq = platform_get_irq(pdev, 1);
1293 
1294 	if (host->use_dma && davinci_acquire_dma_channels(host) != 0)
1295 		host->use_dma = 0;
1296 
1297 	/* REVISIT:  someday, support IRQ-driven card detection.  */
1298 	mmc->caps |= MMC_CAP_NEEDS_POLL;
1299 	mmc->caps |= MMC_CAP_WAIT_WHILE_BUSY;
1300 
1301 	if (pdata && (pdata->wires == 4 || pdata->wires == 0))
1302 		mmc->caps |= MMC_CAP_4_BIT_DATA;
1303 
1304 	if (pdata && (pdata->wires == 8))
1305 		mmc->caps |= (MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA);
1306 
1307 	id_entry = platform_get_device_id(pdev);
1308 	if (id_entry)
1309 		host->version = id_entry->driver_data;
1310 
1311 	mmc->ops = &mmc_davinci_ops;
1312 	mmc->f_min = 312500;
1313 	mmc->f_max = 25000000;
1314 	if (pdata && pdata->max_freq)
1315 		mmc->f_max = pdata->max_freq;
1316 	if (pdata && pdata->caps)
1317 		mmc->caps |= pdata->caps;
1318 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1319 
1320 	/* With no iommu coalescing pages, each phys_seg is a hw_seg.
1321 	 * Each hw_seg uses one EDMA parameter RAM slot, always one
1322 	 * channel and then usually some linked slots.
1323 	 */
1324 	mmc->max_segs		= MAX_NR_SG;
1325 
1326 	/* EDMA limit per hw segment (one or two MBytes) */
1327 	mmc->max_seg_size	= MAX_CCNT * rw_threshold;
1328 
1329 	/* MMC/SD controller limits for multiblock requests */
1330 	mmc->max_blk_size	= 4095;  /* BLEN is 12 bits */
1331 	mmc->max_blk_count	= 65535; /* NBLK is 16 bits */
1332 	mmc->max_req_size	= mmc->max_blk_size * mmc->max_blk_count;
1333 
1334 	dev_dbg(mmc_dev(host->mmc), "max_segs=%d\n", mmc->max_segs);
1335 	dev_dbg(mmc_dev(host->mmc), "max_blk_size=%d\n", mmc->max_blk_size);
1336 	dev_dbg(mmc_dev(host->mmc), "max_req_size=%d\n", mmc->max_req_size);
1337 	dev_dbg(mmc_dev(host->mmc), "max_seg_size=%d\n", mmc->max_seg_size);
1338 
1339 	platform_set_drvdata(pdev, host);
1340 
1341 	ret = mmc_davinci_cpufreq_register(host);
1342 	if (ret) {
1343 		dev_err(&pdev->dev, "failed to register cpufreq\n");
1344 		goto cpu_freq_fail;
1345 	}
1346 
1347 	ret = mmc_add_host(mmc);
1348 	if (ret < 0)
1349 		goto out;
1350 
1351 	ret = request_irq(irq, mmc_davinci_irq, 0, mmc_hostname(mmc), host);
1352 	if (ret)
1353 		goto out;
1354 
1355 	if (host->sdio_irq >= 0) {
1356 		ret = request_irq(host->sdio_irq, mmc_davinci_sdio_irq, 0,
1357 				  mmc_hostname(mmc), host);
1358 		if (!ret)
1359 			mmc->caps |= MMC_CAP_SDIO_IRQ;
1360 	}
1361 
1362 	rename_region(mem, mmc_hostname(mmc));
1363 
1364 	dev_info(mmc_dev(host->mmc), "Using %s, %d-bit mode\n",
1365 		host->use_dma ? "DMA" : "PIO",
1366 		(mmc->caps & MMC_CAP_4_BIT_DATA) ? 4 : 1);
1367 
1368 	return 0;
1369 
1370 out:
1371 	mmc_davinci_cpufreq_deregister(host);
1372 cpu_freq_fail:
1373 	if (host) {
1374 		davinci_release_dma_channels(host);
1375 
1376 		if (host->clk) {
1377 			clk_disable(host->clk);
1378 			clk_put(host->clk);
1379 		}
1380 
1381 		if (host->base)
1382 			iounmap(host->base);
1383 	}
1384 
1385 	if (mmc)
1386 		mmc_free_host(mmc);
1387 
1388 	if (mem)
1389 		release_resource(mem);
1390 
1391 	dev_dbg(&pdev->dev, "probe err %d\n", ret);
1392 
1393 	return ret;
1394 }
1395 
1396 static int __exit davinci_mmcsd_remove(struct platform_device *pdev)
1397 {
1398 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
1399 
1400 	if (host) {
1401 		mmc_davinci_cpufreq_deregister(host);
1402 
1403 		mmc_remove_host(host->mmc);
1404 		free_irq(host->mmc_irq, host);
1405 		if (host->mmc->caps & MMC_CAP_SDIO_IRQ)
1406 			free_irq(host->sdio_irq, host);
1407 
1408 		davinci_release_dma_channels(host);
1409 
1410 		clk_disable(host->clk);
1411 		clk_put(host->clk);
1412 
1413 		iounmap(host->base);
1414 
1415 		release_resource(host->mem_res);
1416 
1417 		mmc_free_host(host->mmc);
1418 	}
1419 
1420 	return 0;
1421 }
1422 
1423 #ifdef CONFIG_PM
1424 static int davinci_mmcsd_suspend(struct device *dev)
1425 {
1426 	struct platform_device *pdev = to_platform_device(dev);
1427 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
1428 
1429 	writel(0, host->base + DAVINCI_MMCIM);
1430 	mmc_davinci_reset_ctrl(host, 1);
1431 	clk_disable(host->clk);
1432 
1433 	return 0;
1434 }
1435 
1436 static int davinci_mmcsd_resume(struct device *dev)
1437 {
1438 	struct platform_device *pdev = to_platform_device(dev);
1439 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
1440 
1441 	clk_enable(host->clk);
1442 	mmc_davinci_reset_ctrl(host, 0);
1443 
1444 	return 0;
1445 }
1446 
1447 static const struct dev_pm_ops davinci_mmcsd_pm = {
1448 	.suspend        = davinci_mmcsd_suspend,
1449 	.resume         = davinci_mmcsd_resume,
1450 };
1451 
1452 #define davinci_mmcsd_pm_ops (&davinci_mmcsd_pm)
1453 #else
1454 #define davinci_mmcsd_pm_ops NULL
1455 #endif
1456 
1457 static struct platform_driver davinci_mmcsd_driver = {
1458 	.driver		= {
1459 		.name	= "davinci_mmc",
1460 		.pm	= davinci_mmcsd_pm_ops,
1461 		.of_match_table = davinci_mmc_dt_ids,
1462 	},
1463 	.remove		= __exit_p(davinci_mmcsd_remove),
1464 	.id_table	= davinci_mmc_devtype,
1465 };
1466 
1467 module_platform_driver_probe(davinci_mmcsd_driver, davinci_mmcsd_probe);
1468 
1469 MODULE_AUTHOR("Texas Instruments India");
1470 MODULE_LICENSE("GPL");
1471 MODULE_DESCRIPTION("MMC/SD driver for Davinci MMC controller");
1472 MODULE_ALIAS("platform:davinci_mmc");
1473 
1474