xref: /openbmc/linux/drivers/mmc/host/davinci_mmc.c (revision 275876e2)
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 stream or block transfer */
350 	if (cmd->flags & MMC_DATA_STREAM)
351 		cmd_reg |= MMCCMD_STRMTP;
352 
353 	/* Setting whether data read or write */
354 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE)
355 		cmd_reg |= MMCCMD_DTRW;
356 
357 	if (host->bus_mode == MMC_BUSMODE_PUSHPULL)
358 		cmd_reg |= MMCCMD_PPLEN;
359 
360 	/* set Command timeout */
361 	writel(0x1FFF, host->base + DAVINCI_MMCTOR);
362 
363 	/* Enable interrupt (calculate here, defer until FIFO is stuffed). */
364 	im_val =  MMCST0_RSPDNE | MMCST0_CRCRS | MMCST0_TOUTRS;
365 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE) {
366 		im_val |= MMCST0_DATDNE | MMCST0_CRCWR;
367 
368 		if (!host->do_dma)
369 			im_val |= MMCST0_DXRDY;
370 	} else if (host->data_dir == DAVINCI_MMC_DATADIR_READ) {
371 		im_val |= MMCST0_DATDNE | MMCST0_CRCRD | MMCST0_TOUTRD;
372 
373 		if (!host->do_dma)
374 			im_val |= MMCST0_DRRDY;
375 	}
376 
377 	/*
378 	 * Before non-DMA WRITE commands the controller needs priming:
379 	 * FIFO should be populated with 32 bytes i.e. whatever is the FIFO size
380 	 */
381 	if (!host->do_dma && (host->data_dir == DAVINCI_MMC_DATADIR_WRITE))
382 		davinci_fifo_data_trans(host, rw_threshold);
383 
384 	writel(cmd->arg, host->base + DAVINCI_MMCARGHL);
385 	writel(cmd_reg,  host->base + DAVINCI_MMCCMD);
386 
387 	host->active_request = true;
388 
389 	if (!host->do_dma && host->bytes_left <= poll_threshold) {
390 		u32 count = poll_loopcount;
391 
392 		while (host->active_request && count--) {
393 			mmc_davinci_irq(0, host);
394 			cpu_relax();
395 		}
396 	}
397 
398 	if (host->active_request)
399 		writel(im_val, host->base + DAVINCI_MMCIM);
400 }
401 
402 /*----------------------------------------------------------------------*/
403 
404 /* DMA infrastructure */
405 
406 static void davinci_abort_dma(struct mmc_davinci_host *host)
407 {
408 	struct dma_chan *sync_dev;
409 
410 	if (host->data_dir == DAVINCI_MMC_DATADIR_READ)
411 		sync_dev = host->dma_rx;
412 	else
413 		sync_dev = host->dma_tx;
414 
415 	dmaengine_terminate_all(sync_dev);
416 }
417 
418 static int mmc_davinci_send_dma_request(struct mmc_davinci_host *host,
419 		struct mmc_data *data)
420 {
421 	struct dma_chan *chan;
422 	struct dma_async_tx_descriptor *desc;
423 	int ret = 0;
424 
425 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE) {
426 		struct dma_slave_config dma_tx_conf = {
427 			.direction = DMA_MEM_TO_DEV,
428 			.dst_addr = host->mem_res->start + DAVINCI_MMCDXR,
429 			.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
430 			.dst_maxburst =
431 				rw_threshold / DMA_SLAVE_BUSWIDTH_4_BYTES,
432 		};
433 		chan = host->dma_tx;
434 		dmaengine_slave_config(host->dma_tx, &dma_tx_conf);
435 
436 		desc = dmaengine_prep_slave_sg(host->dma_tx,
437 				data->sg,
438 				host->sg_len,
439 				DMA_MEM_TO_DEV,
440 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
441 		if (!desc) {
442 			dev_dbg(mmc_dev(host->mmc),
443 				"failed to allocate DMA TX descriptor");
444 			ret = -1;
445 			goto out;
446 		}
447 	} else {
448 		struct dma_slave_config dma_rx_conf = {
449 			.direction = DMA_DEV_TO_MEM,
450 			.src_addr = host->mem_res->start + DAVINCI_MMCDRR,
451 			.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
452 			.src_maxburst =
453 				rw_threshold / DMA_SLAVE_BUSWIDTH_4_BYTES,
454 		};
455 		chan = host->dma_rx;
456 		dmaengine_slave_config(host->dma_rx, &dma_rx_conf);
457 
458 		desc = dmaengine_prep_slave_sg(host->dma_rx,
459 				data->sg,
460 				host->sg_len,
461 				DMA_DEV_TO_MEM,
462 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
463 		if (!desc) {
464 			dev_dbg(mmc_dev(host->mmc),
465 				"failed to allocate DMA RX descriptor");
466 			ret = -1;
467 			goto out;
468 		}
469 	}
470 
471 	dmaengine_submit(desc);
472 	dma_async_issue_pending(chan);
473 
474 out:
475 	return ret;
476 }
477 
478 static int mmc_davinci_start_dma_transfer(struct mmc_davinci_host *host,
479 		struct mmc_data *data)
480 {
481 	int i;
482 	int mask = rw_threshold - 1;
483 	int ret = 0;
484 
485 	host->sg_len = dma_map_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
486 				((data->flags & MMC_DATA_WRITE)
487 				? DMA_TO_DEVICE
488 				: DMA_FROM_DEVICE));
489 
490 	/* no individual DMA segment should need a partial FIFO */
491 	for (i = 0; i < host->sg_len; i++) {
492 		if (sg_dma_len(data->sg + i) & mask) {
493 			dma_unmap_sg(mmc_dev(host->mmc),
494 					data->sg, data->sg_len,
495 					(data->flags & MMC_DATA_WRITE)
496 					? DMA_TO_DEVICE
497 					: DMA_FROM_DEVICE);
498 			return -1;
499 		}
500 	}
501 
502 	host->do_dma = 1;
503 	ret = mmc_davinci_send_dma_request(host, data);
504 
505 	return ret;
506 }
507 
508 static void __init_or_module
509 davinci_release_dma_channels(struct mmc_davinci_host *host)
510 {
511 	if (!host->use_dma)
512 		return;
513 
514 	dma_release_channel(host->dma_tx);
515 	dma_release_channel(host->dma_rx);
516 }
517 
518 static int __init davinci_acquire_dma_channels(struct mmc_davinci_host *host)
519 {
520 	int r;
521 	dma_cap_mask_t mask;
522 
523 	dma_cap_zero(mask);
524 	dma_cap_set(DMA_SLAVE, mask);
525 
526 	host->dma_tx =
527 		dma_request_slave_channel_compat(mask, edma_filter_fn,
528 				&host->txdma, mmc_dev(host->mmc), "tx");
529 	if (!host->dma_tx) {
530 		dev_err(mmc_dev(host->mmc), "Can't get dma_tx channel\n");
531 		return -ENODEV;
532 	}
533 
534 	host->dma_rx =
535 		dma_request_slave_channel_compat(mask, edma_filter_fn,
536 				&host->rxdma, mmc_dev(host->mmc), "rx");
537 	if (!host->dma_rx) {
538 		dev_err(mmc_dev(host->mmc), "Can't get dma_rx channel\n");
539 		r = -ENODEV;
540 		goto free_master_write;
541 	}
542 
543 	return 0;
544 
545 free_master_write:
546 	dma_release_channel(host->dma_tx);
547 
548 	return r;
549 }
550 
551 /*----------------------------------------------------------------------*/
552 
553 static void
554 mmc_davinci_prepare_data(struct mmc_davinci_host *host, struct mmc_request *req)
555 {
556 	int fifo_lev = (rw_threshold == 32) ? MMCFIFOCTL_FIFOLEV : 0;
557 	int timeout;
558 	struct mmc_data *data = req->data;
559 
560 	if (host->version == MMC_CTLR_VERSION_2)
561 		fifo_lev = (rw_threshold == 64) ? MMCFIFOCTL_FIFOLEV : 0;
562 
563 	host->data = data;
564 	if (data == NULL) {
565 		host->data_dir = DAVINCI_MMC_DATADIR_NONE;
566 		writel(0, host->base + DAVINCI_MMCBLEN);
567 		writel(0, host->base + DAVINCI_MMCNBLK);
568 		return;
569 	}
570 
571 	dev_dbg(mmc_dev(host->mmc), "%s %s, %d blocks of %d bytes\n",
572 		(data->flags & MMC_DATA_STREAM) ? "stream" : "block",
573 		(data->flags & MMC_DATA_WRITE) ? "write" : "read",
574 		data->blocks, data->blksz);
575 	dev_dbg(mmc_dev(host->mmc), "  DTO %d cycles + %d ns\n",
576 		data->timeout_clks, data->timeout_ns);
577 	timeout = data->timeout_clks +
578 		(data->timeout_ns / host->ns_in_one_cycle);
579 	if (timeout > 0xffff)
580 		timeout = 0xffff;
581 
582 	writel(timeout, host->base + DAVINCI_MMCTOD);
583 	writel(data->blocks, host->base + DAVINCI_MMCNBLK);
584 	writel(data->blksz, host->base + DAVINCI_MMCBLEN);
585 
586 	/* Configure the FIFO */
587 	switch (data->flags & MMC_DATA_WRITE) {
588 	case MMC_DATA_WRITE:
589 		host->data_dir = DAVINCI_MMC_DATADIR_WRITE;
590 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_WR | MMCFIFOCTL_FIFORST,
591 			host->base + DAVINCI_MMCFIFOCTL);
592 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_WR,
593 			host->base + DAVINCI_MMCFIFOCTL);
594 		break;
595 
596 	default:
597 		host->data_dir = DAVINCI_MMC_DATADIR_READ;
598 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_RD | MMCFIFOCTL_FIFORST,
599 			host->base + DAVINCI_MMCFIFOCTL);
600 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_RD,
601 			host->base + DAVINCI_MMCFIFOCTL);
602 		break;
603 	}
604 
605 	host->buffer = NULL;
606 	host->bytes_left = data->blocks * data->blksz;
607 
608 	/* For now we try to use DMA whenever we won't need partial FIFO
609 	 * reads or writes, either for the whole transfer (as tested here)
610 	 * or for any individual scatterlist segment (tested when we call
611 	 * start_dma_transfer).
612 	 *
613 	 * While we *could* change that, unusual block sizes are rarely
614 	 * used.  The occasional fallback to PIO should't hurt.
615 	 */
616 	if (host->use_dma && (host->bytes_left & (rw_threshold - 1)) == 0
617 			&& mmc_davinci_start_dma_transfer(host, data) == 0) {
618 		/* zero this to ensure we take no PIO paths */
619 		host->bytes_left = 0;
620 	} else {
621 		/* Revert to CPU Copy */
622 		host->sg_len = data->sg_len;
623 		host->sg = host->data->sg;
624 		mmc_davinci_sg_to_buf(host);
625 	}
626 }
627 
628 static void mmc_davinci_request(struct mmc_host *mmc, struct mmc_request *req)
629 {
630 	struct mmc_davinci_host *host = mmc_priv(mmc);
631 	unsigned long timeout = jiffies + msecs_to_jiffies(900);
632 	u32 mmcst1 = 0;
633 
634 	/* Card may still be sending BUSY after a previous operation,
635 	 * typically some kind of write.  If so, we can't proceed yet.
636 	 */
637 	while (time_before(jiffies, timeout)) {
638 		mmcst1  = readl(host->base + DAVINCI_MMCST1);
639 		if (!(mmcst1 & MMCST1_BUSY))
640 			break;
641 		cpu_relax();
642 	}
643 	if (mmcst1 & MMCST1_BUSY) {
644 		dev_err(mmc_dev(host->mmc), "still BUSY? bad ... \n");
645 		req->cmd->error = -ETIMEDOUT;
646 		mmc_request_done(mmc, req);
647 		return;
648 	}
649 
650 	host->do_dma = 0;
651 	mmc_davinci_prepare_data(host, req);
652 	mmc_davinci_start_command(host, req->cmd);
653 }
654 
655 static unsigned int calculate_freq_for_card(struct mmc_davinci_host *host,
656 	unsigned int mmc_req_freq)
657 {
658 	unsigned int mmc_freq = 0, mmc_pclk = 0, mmc_push_pull_divisor = 0;
659 
660 	mmc_pclk = host->mmc_input_clk;
661 	if (mmc_req_freq && mmc_pclk > (2 * mmc_req_freq))
662 		mmc_push_pull_divisor = ((unsigned int)mmc_pclk
663 				/ (2 * mmc_req_freq)) - 1;
664 	else
665 		mmc_push_pull_divisor = 0;
666 
667 	mmc_freq = (unsigned int)mmc_pclk
668 		/ (2 * (mmc_push_pull_divisor + 1));
669 
670 	if (mmc_freq > mmc_req_freq)
671 		mmc_push_pull_divisor = mmc_push_pull_divisor + 1;
672 	/* Convert ns to clock cycles */
673 	if (mmc_req_freq <= 400000)
674 		host->ns_in_one_cycle = (1000000) / (((mmc_pclk
675 				/ (2 * (mmc_push_pull_divisor + 1)))/1000));
676 	else
677 		host->ns_in_one_cycle = (1000000) / (((mmc_pclk
678 				/ (2 * (mmc_push_pull_divisor + 1)))/1000000));
679 
680 	return mmc_push_pull_divisor;
681 }
682 
683 static void calculate_clk_divider(struct mmc_host *mmc, struct mmc_ios *ios)
684 {
685 	unsigned int open_drain_freq = 0, mmc_pclk = 0;
686 	unsigned int mmc_push_pull_freq = 0;
687 	struct mmc_davinci_host *host = mmc_priv(mmc);
688 
689 	if (ios->bus_mode == MMC_BUSMODE_OPENDRAIN) {
690 		u32 temp;
691 
692 		/* Ignoring the init clock value passed for fixing the inter
693 		 * operability with different cards.
694 		 */
695 		open_drain_freq = ((unsigned int)mmc_pclk
696 				/ (2 * MMCSD_INIT_CLOCK)) - 1;
697 
698 		if (open_drain_freq > 0xFF)
699 			open_drain_freq = 0xFF;
700 
701 		temp = readl(host->base + DAVINCI_MMCCLK) & ~MMCCLK_CLKRT_MASK;
702 		temp |= open_drain_freq;
703 		writel(temp, host->base + DAVINCI_MMCCLK);
704 
705 		/* Convert ns to clock cycles */
706 		host->ns_in_one_cycle = (1000000) / (MMCSD_INIT_CLOCK/1000);
707 	} else {
708 		u32 temp;
709 		mmc_push_pull_freq = calculate_freq_for_card(host, ios->clock);
710 
711 		if (mmc_push_pull_freq > 0xFF)
712 			mmc_push_pull_freq = 0xFF;
713 
714 		temp = readl(host->base + DAVINCI_MMCCLK) & ~MMCCLK_CLKEN;
715 		writel(temp, host->base + DAVINCI_MMCCLK);
716 
717 		udelay(10);
718 
719 		temp = readl(host->base + DAVINCI_MMCCLK) & ~MMCCLK_CLKRT_MASK;
720 		temp |= mmc_push_pull_freq;
721 		writel(temp, host->base + DAVINCI_MMCCLK);
722 
723 		writel(temp | MMCCLK_CLKEN, host->base + DAVINCI_MMCCLK);
724 
725 		udelay(10);
726 	}
727 }
728 
729 static void mmc_davinci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
730 {
731 	struct mmc_davinci_host *host = mmc_priv(mmc);
732 	struct platform_device *pdev = to_platform_device(mmc->parent);
733 	struct davinci_mmc_config *config = pdev->dev.platform_data;
734 
735 	dev_dbg(mmc_dev(host->mmc),
736 		"clock %dHz busmode %d powermode %d Vdd %04x\n",
737 		ios->clock, ios->bus_mode, ios->power_mode,
738 		ios->vdd);
739 
740 	switch (ios->power_mode) {
741 	case MMC_POWER_OFF:
742 		if (config && config->set_power)
743 			config->set_power(pdev->id, false);
744 		break;
745 	case MMC_POWER_UP:
746 		if (config && config->set_power)
747 			config->set_power(pdev->id, true);
748 		break;
749 	}
750 
751 	switch (ios->bus_width) {
752 	case MMC_BUS_WIDTH_8:
753 		dev_dbg(mmc_dev(host->mmc), "Enabling 8 bit mode\n");
754 		writel((readl(host->base + DAVINCI_MMCCTL) &
755 			~MMCCTL_WIDTH_4_BIT) | MMCCTL_WIDTH_8_BIT,
756 			host->base + DAVINCI_MMCCTL);
757 		break;
758 	case MMC_BUS_WIDTH_4:
759 		dev_dbg(mmc_dev(host->mmc), "Enabling 4 bit mode\n");
760 		if (host->version == MMC_CTLR_VERSION_2)
761 			writel((readl(host->base + DAVINCI_MMCCTL) &
762 				~MMCCTL_WIDTH_8_BIT) | MMCCTL_WIDTH_4_BIT,
763 				host->base + DAVINCI_MMCCTL);
764 		else
765 			writel(readl(host->base + DAVINCI_MMCCTL) |
766 				MMCCTL_WIDTH_4_BIT,
767 				host->base + DAVINCI_MMCCTL);
768 		break;
769 	case MMC_BUS_WIDTH_1:
770 		dev_dbg(mmc_dev(host->mmc), "Enabling 1 bit mode\n");
771 		if (host->version == MMC_CTLR_VERSION_2)
772 			writel(readl(host->base + DAVINCI_MMCCTL) &
773 				~(MMCCTL_WIDTH_8_BIT | MMCCTL_WIDTH_4_BIT),
774 				host->base + DAVINCI_MMCCTL);
775 		else
776 			writel(readl(host->base + DAVINCI_MMCCTL) &
777 				~MMCCTL_WIDTH_4_BIT,
778 				host->base + DAVINCI_MMCCTL);
779 		break;
780 	}
781 
782 	calculate_clk_divider(mmc, ios);
783 
784 	host->bus_mode = ios->bus_mode;
785 	if (ios->power_mode == MMC_POWER_UP) {
786 		unsigned long timeout = jiffies + msecs_to_jiffies(50);
787 		bool lose = true;
788 
789 		/* Send clock cycles, poll completion */
790 		writel(0, host->base + DAVINCI_MMCARGHL);
791 		writel(MMCCMD_INITCK, host->base + DAVINCI_MMCCMD);
792 		while (time_before(jiffies, timeout)) {
793 			u32 tmp = readl(host->base + DAVINCI_MMCST0);
794 
795 			if (tmp & MMCST0_RSPDNE) {
796 				lose = false;
797 				break;
798 			}
799 			cpu_relax();
800 		}
801 		if (lose)
802 			dev_warn(mmc_dev(host->mmc), "powerup timeout\n");
803 	}
804 
805 	/* FIXME on power OFF, reset things ... */
806 }
807 
808 static void
809 mmc_davinci_xfer_done(struct mmc_davinci_host *host, struct mmc_data *data)
810 {
811 	host->data = NULL;
812 
813 	if (host->mmc->caps & MMC_CAP_SDIO_IRQ) {
814 		/*
815 		 * SDIO Interrupt Detection work-around as suggested by
816 		 * Davinci Errata (TMS320DM355 Silicon Revision 1.1 Errata
817 		 * 2.1.6): Signal SDIO interrupt only if it is enabled by core
818 		 */
819 		if (host->sdio_int && !(readl(host->base + DAVINCI_SDIOST0) &
820 					SDIOST0_DAT1_HI)) {
821 			writel(SDIOIST_IOINT, host->base + DAVINCI_SDIOIST);
822 			mmc_signal_sdio_irq(host->mmc);
823 		}
824 	}
825 
826 	if (host->do_dma) {
827 		davinci_abort_dma(host);
828 
829 		dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
830 			     (data->flags & MMC_DATA_WRITE)
831 			     ? DMA_TO_DEVICE
832 			     : DMA_FROM_DEVICE);
833 		host->do_dma = false;
834 	}
835 	host->data_dir = DAVINCI_MMC_DATADIR_NONE;
836 
837 	if (!data->stop || (host->cmd && host->cmd->error)) {
838 		mmc_request_done(host->mmc, data->mrq);
839 		writel(0, host->base + DAVINCI_MMCIM);
840 		host->active_request = false;
841 	} else
842 		mmc_davinci_start_command(host, data->stop);
843 }
844 
845 static void mmc_davinci_cmd_done(struct mmc_davinci_host *host,
846 				 struct mmc_command *cmd)
847 {
848 	host->cmd = NULL;
849 
850 	if (cmd->flags & MMC_RSP_PRESENT) {
851 		if (cmd->flags & MMC_RSP_136) {
852 			/* response type 2 */
853 			cmd->resp[3] = readl(host->base + DAVINCI_MMCRSP01);
854 			cmd->resp[2] = readl(host->base + DAVINCI_MMCRSP23);
855 			cmd->resp[1] = readl(host->base + DAVINCI_MMCRSP45);
856 			cmd->resp[0] = readl(host->base + DAVINCI_MMCRSP67);
857 		} else {
858 			/* response types 1, 1b, 3, 4, 5, 6 */
859 			cmd->resp[0] = readl(host->base + DAVINCI_MMCRSP67);
860 		}
861 	}
862 
863 	if (host->data == NULL || cmd->error) {
864 		if (cmd->error == -ETIMEDOUT)
865 			cmd->mrq->cmd->retries = 0;
866 		mmc_request_done(host->mmc, cmd->mrq);
867 		writel(0, host->base + DAVINCI_MMCIM);
868 		host->active_request = false;
869 	}
870 }
871 
872 static inline void mmc_davinci_reset_ctrl(struct mmc_davinci_host *host,
873 								int val)
874 {
875 	u32 temp;
876 
877 	temp = readl(host->base + DAVINCI_MMCCTL);
878 	if (val)	/* reset */
879 		temp |= MMCCTL_CMDRST | MMCCTL_DATRST;
880 	else		/* enable */
881 		temp &= ~(MMCCTL_CMDRST | MMCCTL_DATRST);
882 
883 	writel(temp, host->base + DAVINCI_MMCCTL);
884 	udelay(10);
885 }
886 
887 static void
888 davinci_abort_data(struct mmc_davinci_host *host, struct mmc_data *data)
889 {
890 	mmc_davinci_reset_ctrl(host, 1);
891 	mmc_davinci_reset_ctrl(host, 0);
892 }
893 
894 static irqreturn_t mmc_davinci_sdio_irq(int irq, void *dev_id)
895 {
896 	struct mmc_davinci_host *host = dev_id;
897 	unsigned int status;
898 
899 	status = readl(host->base + DAVINCI_SDIOIST);
900 	if (status & SDIOIST_IOINT) {
901 		dev_dbg(mmc_dev(host->mmc),
902 			"SDIO interrupt status %x\n", status);
903 		writel(status | SDIOIST_IOINT, host->base + DAVINCI_SDIOIST);
904 		mmc_signal_sdio_irq(host->mmc);
905 	}
906 	return IRQ_HANDLED;
907 }
908 
909 static irqreturn_t mmc_davinci_irq(int irq, void *dev_id)
910 {
911 	struct mmc_davinci_host *host = (struct mmc_davinci_host *)dev_id;
912 	unsigned int status, qstatus;
913 	int end_command = 0;
914 	int end_transfer = 0;
915 	struct mmc_data *data = host->data;
916 
917 	if (host->cmd == NULL && host->data == NULL) {
918 		status = readl(host->base + DAVINCI_MMCST0);
919 		dev_dbg(mmc_dev(host->mmc),
920 			"Spurious interrupt 0x%04x\n", status);
921 		/* Disable the interrupt from mmcsd */
922 		writel(0, host->base + DAVINCI_MMCIM);
923 		return IRQ_NONE;
924 	}
925 
926 	status = readl(host->base + DAVINCI_MMCST0);
927 	qstatus = status;
928 
929 	/* handle FIFO first when using PIO for data.
930 	 * bytes_left will decrease to zero as I/O progress and status will
931 	 * read zero over iteration because this controller status
932 	 * register(MMCST0) reports any status only once and it is cleared
933 	 * by read. So, it is not unbouned loop even in the case of
934 	 * non-dma.
935 	 */
936 	if (host->bytes_left && (status & (MMCST0_DXRDY | MMCST0_DRRDY))) {
937 		unsigned long im_val;
938 
939 		/*
940 		 * If interrupts fire during the following loop, they will be
941 		 * handled by the handler, but the PIC will still buffer these.
942 		 * As a result, the handler will be called again to serve these
943 		 * needlessly. In order to avoid these spurious interrupts,
944 		 * keep interrupts masked during the loop.
945 		 */
946 		im_val = readl(host->base + DAVINCI_MMCIM);
947 		writel(0, host->base + DAVINCI_MMCIM);
948 
949 		do {
950 			davinci_fifo_data_trans(host, rw_threshold);
951 			status = readl(host->base + DAVINCI_MMCST0);
952 			qstatus |= status;
953 		} while (host->bytes_left &&
954 			 (status & (MMCST0_DXRDY | MMCST0_DRRDY)));
955 
956 		/*
957 		 * If an interrupt is pending, it is assumed it will fire when
958 		 * it is unmasked. This assumption is also taken when the MMCIM
959 		 * is first set. Otherwise, writing to MMCIM after reading the
960 		 * status is race-prone.
961 		 */
962 		writel(im_val, host->base + DAVINCI_MMCIM);
963 	}
964 
965 	if (qstatus & MMCST0_DATDNE) {
966 		/* All blocks sent/received, and CRC checks passed */
967 		if (data != NULL) {
968 			if ((host->do_dma == 0) && (host->bytes_left > 0)) {
969 				/* if datasize < rw_threshold
970 				 * no RX ints are generated
971 				 */
972 				davinci_fifo_data_trans(host, host->bytes_left);
973 			}
974 			end_transfer = 1;
975 			data->bytes_xfered = data->blocks * data->blksz;
976 		} else {
977 			dev_err(mmc_dev(host->mmc),
978 					"DATDNE with no host->data\n");
979 		}
980 	}
981 
982 	if (qstatus & MMCST0_TOUTRD) {
983 		/* Read data timeout */
984 		data->error = -ETIMEDOUT;
985 		end_transfer = 1;
986 
987 		dev_dbg(mmc_dev(host->mmc),
988 			"read data timeout, status %x\n",
989 			qstatus);
990 
991 		davinci_abort_data(host, data);
992 	}
993 
994 	if (qstatus & (MMCST0_CRCWR | MMCST0_CRCRD)) {
995 		/* Data CRC error */
996 		data->error = -EILSEQ;
997 		end_transfer = 1;
998 
999 		/* NOTE:  this controller uses CRCWR to report both CRC
1000 		 * errors and timeouts (on writes).  MMCDRSP values are
1001 		 * only weakly documented, but 0x9f was clearly a timeout
1002 		 * case and the two three-bit patterns in various SD specs
1003 		 * (101, 010) aren't part of it ...
1004 		 */
1005 		if (qstatus & MMCST0_CRCWR) {
1006 			u32 temp = readb(host->base + DAVINCI_MMCDRSP);
1007 
1008 			if (temp == 0x9f)
1009 				data->error = -ETIMEDOUT;
1010 		}
1011 		dev_dbg(mmc_dev(host->mmc), "data %s %s error\n",
1012 			(qstatus & MMCST0_CRCWR) ? "write" : "read",
1013 			(data->error == -ETIMEDOUT) ? "timeout" : "CRC");
1014 
1015 		davinci_abort_data(host, data);
1016 	}
1017 
1018 	if (qstatus & MMCST0_TOUTRS) {
1019 		/* Command timeout */
1020 		if (host->cmd) {
1021 			dev_dbg(mmc_dev(host->mmc),
1022 				"CMD%d timeout, status %x\n",
1023 				host->cmd->opcode, qstatus);
1024 			host->cmd->error = -ETIMEDOUT;
1025 			if (data) {
1026 				end_transfer = 1;
1027 				davinci_abort_data(host, data);
1028 			} else
1029 				end_command = 1;
1030 		}
1031 	}
1032 
1033 	if (qstatus & MMCST0_CRCRS) {
1034 		/* Command CRC error */
1035 		dev_dbg(mmc_dev(host->mmc), "Command CRC error\n");
1036 		if (host->cmd) {
1037 			host->cmd->error = -EILSEQ;
1038 			end_command = 1;
1039 		}
1040 	}
1041 
1042 	if (qstatus & MMCST0_RSPDNE) {
1043 		/* End of command phase */
1044 		end_command = (int) host->cmd;
1045 	}
1046 
1047 	if (end_command)
1048 		mmc_davinci_cmd_done(host, host->cmd);
1049 	if (end_transfer)
1050 		mmc_davinci_xfer_done(host, data);
1051 	return IRQ_HANDLED;
1052 }
1053 
1054 static int mmc_davinci_get_cd(struct mmc_host *mmc)
1055 {
1056 	struct platform_device *pdev = to_platform_device(mmc->parent);
1057 	struct davinci_mmc_config *config = pdev->dev.platform_data;
1058 
1059 	if (!config || !config->get_cd)
1060 		return -ENOSYS;
1061 	return config->get_cd(pdev->id);
1062 }
1063 
1064 static int mmc_davinci_get_ro(struct mmc_host *mmc)
1065 {
1066 	struct platform_device *pdev = to_platform_device(mmc->parent);
1067 	struct davinci_mmc_config *config = pdev->dev.platform_data;
1068 
1069 	if (!config || !config->get_ro)
1070 		return -ENOSYS;
1071 	return config->get_ro(pdev->id);
1072 }
1073 
1074 static void mmc_davinci_enable_sdio_irq(struct mmc_host *mmc, int enable)
1075 {
1076 	struct mmc_davinci_host *host = mmc_priv(mmc);
1077 
1078 	if (enable) {
1079 		if (!(readl(host->base + DAVINCI_SDIOST0) & SDIOST0_DAT1_HI)) {
1080 			writel(SDIOIST_IOINT, host->base + DAVINCI_SDIOIST);
1081 			mmc_signal_sdio_irq(host->mmc);
1082 		} else {
1083 			host->sdio_int = true;
1084 			writel(readl(host->base + DAVINCI_SDIOIEN) |
1085 			       SDIOIEN_IOINTEN, host->base + DAVINCI_SDIOIEN);
1086 		}
1087 	} else {
1088 		host->sdio_int = false;
1089 		writel(readl(host->base + DAVINCI_SDIOIEN) & ~SDIOIEN_IOINTEN,
1090 		       host->base + DAVINCI_SDIOIEN);
1091 	}
1092 }
1093 
1094 static struct mmc_host_ops mmc_davinci_ops = {
1095 	.request	= mmc_davinci_request,
1096 	.set_ios	= mmc_davinci_set_ios,
1097 	.get_cd		= mmc_davinci_get_cd,
1098 	.get_ro		= mmc_davinci_get_ro,
1099 	.enable_sdio_irq = mmc_davinci_enable_sdio_irq,
1100 };
1101 
1102 /*----------------------------------------------------------------------*/
1103 
1104 #ifdef CONFIG_CPU_FREQ
1105 static int mmc_davinci_cpufreq_transition(struct notifier_block *nb,
1106 				     unsigned long val, void *data)
1107 {
1108 	struct mmc_davinci_host *host;
1109 	unsigned int mmc_pclk;
1110 	struct mmc_host *mmc;
1111 	unsigned long flags;
1112 
1113 	host = container_of(nb, struct mmc_davinci_host, freq_transition);
1114 	mmc = host->mmc;
1115 	mmc_pclk = clk_get_rate(host->clk);
1116 
1117 	if (val == CPUFREQ_POSTCHANGE) {
1118 		spin_lock_irqsave(&mmc->lock, flags);
1119 		host->mmc_input_clk = mmc_pclk;
1120 		calculate_clk_divider(mmc, &mmc->ios);
1121 		spin_unlock_irqrestore(&mmc->lock, flags);
1122 	}
1123 
1124 	return 0;
1125 }
1126 
1127 static inline int mmc_davinci_cpufreq_register(struct mmc_davinci_host *host)
1128 {
1129 	host->freq_transition.notifier_call = mmc_davinci_cpufreq_transition;
1130 
1131 	return cpufreq_register_notifier(&host->freq_transition,
1132 					 CPUFREQ_TRANSITION_NOTIFIER);
1133 }
1134 
1135 static inline void mmc_davinci_cpufreq_deregister(struct mmc_davinci_host *host)
1136 {
1137 	cpufreq_unregister_notifier(&host->freq_transition,
1138 				    CPUFREQ_TRANSITION_NOTIFIER);
1139 }
1140 #else
1141 static inline int mmc_davinci_cpufreq_register(struct mmc_davinci_host *host)
1142 {
1143 	return 0;
1144 }
1145 
1146 static inline void mmc_davinci_cpufreq_deregister(struct mmc_davinci_host *host)
1147 {
1148 }
1149 #endif
1150 static void __init init_mmcsd_host(struct mmc_davinci_host *host)
1151 {
1152 
1153 	mmc_davinci_reset_ctrl(host, 1);
1154 
1155 	writel(0, host->base + DAVINCI_MMCCLK);
1156 	writel(MMCCLK_CLKEN, host->base + DAVINCI_MMCCLK);
1157 
1158 	writel(0x1FFF, host->base + DAVINCI_MMCTOR);
1159 	writel(0xFFFF, host->base + DAVINCI_MMCTOD);
1160 
1161 	mmc_davinci_reset_ctrl(host, 0);
1162 }
1163 
1164 static struct platform_device_id davinci_mmc_devtype[] = {
1165 	{
1166 		.name	= "dm6441-mmc",
1167 		.driver_data = MMC_CTLR_VERSION_1,
1168 	}, {
1169 		.name	= "da830-mmc",
1170 		.driver_data = MMC_CTLR_VERSION_2,
1171 	},
1172 	{},
1173 };
1174 MODULE_DEVICE_TABLE(platform, davinci_mmc_devtype);
1175 
1176 static const struct of_device_id davinci_mmc_dt_ids[] = {
1177 	{
1178 		.compatible = "ti,dm6441-mmc",
1179 		.data = &davinci_mmc_devtype[MMC_CTLR_VERSION_1],
1180 	},
1181 	{
1182 		.compatible = "ti,da830-mmc",
1183 		.data = &davinci_mmc_devtype[MMC_CTLR_VERSION_2],
1184 	},
1185 	{},
1186 };
1187 MODULE_DEVICE_TABLE(of, davinci_mmc_dt_ids);
1188 
1189 static struct davinci_mmc_config
1190 	*mmc_parse_pdata(struct platform_device *pdev)
1191 {
1192 	struct device_node *np;
1193 	struct davinci_mmc_config *pdata = pdev->dev.platform_data;
1194 	const struct of_device_id *match =
1195 		of_match_device(davinci_mmc_dt_ids, &pdev->dev);
1196 	u32 data;
1197 
1198 	np = pdev->dev.of_node;
1199 	if (!np)
1200 		return pdata;
1201 
1202 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
1203 	if (!pdata) {
1204 		dev_err(&pdev->dev, "Failed to allocate memory for struct davinci_mmc_config\n");
1205 		goto nodata;
1206 	}
1207 
1208 	if (match)
1209 		pdev->id_entry = match->data;
1210 
1211 	if (of_property_read_u32(np, "max-frequency", &pdata->max_freq))
1212 		dev_info(&pdev->dev, "'max-frequency' property not specified, defaulting to 25MHz\n");
1213 
1214 	of_property_read_u32(np, "bus-width", &data);
1215 	switch (data) {
1216 	case 1:
1217 	case 4:
1218 	case 8:
1219 		pdata->wires = data;
1220 		break;
1221 	default:
1222 		pdata->wires = 1;
1223 		dev_info(&pdev->dev, "Unsupported buswidth, defaulting to 1 bit\n");
1224 	}
1225 nodata:
1226 	return pdata;
1227 }
1228 
1229 static int __init davinci_mmcsd_probe(struct platform_device *pdev)
1230 {
1231 	struct davinci_mmc_config *pdata = NULL;
1232 	struct mmc_davinci_host *host = NULL;
1233 	struct mmc_host *mmc = NULL;
1234 	struct resource *r, *mem = NULL;
1235 	int ret = 0, irq = 0;
1236 	size_t mem_size;
1237 	const struct platform_device_id *id_entry;
1238 
1239 	pdata = mmc_parse_pdata(pdev);
1240 	if (pdata == NULL) {
1241 		dev_err(&pdev->dev, "Couldn't get platform data\n");
1242 		return -ENOENT;
1243 	}
1244 
1245 	ret = -ENODEV;
1246 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1247 	irq = platform_get_irq(pdev, 0);
1248 	if (!r || irq == NO_IRQ)
1249 		goto out;
1250 
1251 	ret = -EBUSY;
1252 	mem_size = resource_size(r);
1253 	mem = request_mem_region(r->start, mem_size, pdev->name);
1254 	if (!mem)
1255 		goto out;
1256 
1257 	ret = -ENOMEM;
1258 	mmc = mmc_alloc_host(sizeof(struct mmc_davinci_host), &pdev->dev);
1259 	if (!mmc)
1260 		goto out;
1261 
1262 	host = mmc_priv(mmc);
1263 	host->mmc = mmc;	/* Important */
1264 
1265 	r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1266 	if (!r)
1267 		dev_warn(&pdev->dev, "RX DMA resource not specified\n");
1268 	else
1269 		host->rxdma = r->start;
1270 
1271 	r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
1272 	if (!r)
1273 		dev_warn(&pdev->dev, "TX DMA resource not specified\n");
1274 	else
1275 		host->txdma = r->start;
1276 
1277 	host->mem_res = mem;
1278 	host->base = ioremap(mem->start, mem_size);
1279 	if (!host->base)
1280 		goto out;
1281 
1282 	ret = -ENXIO;
1283 	host->clk = clk_get(&pdev->dev, "MMCSDCLK");
1284 	if (IS_ERR(host->clk)) {
1285 		ret = PTR_ERR(host->clk);
1286 		goto out;
1287 	}
1288 	clk_enable(host->clk);
1289 	host->mmc_input_clk = clk_get_rate(host->clk);
1290 
1291 	init_mmcsd_host(host);
1292 
1293 	if (pdata->nr_sg)
1294 		host->nr_sg = pdata->nr_sg - 1;
1295 
1296 	if (host->nr_sg > MAX_NR_SG || !host->nr_sg)
1297 		host->nr_sg = MAX_NR_SG;
1298 
1299 	host->use_dma = use_dma;
1300 	host->mmc_irq = irq;
1301 	host->sdio_irq = platform_get_irq(pdev, 1);
1302 
1303 	if (host->use_dma && davinci_acquire_dma_channels(host) != 0)
1304 		host->use_dma = 0;
1305 
1306 	/* REVISIT:  someday, support IRQ-driven card detection.  */
1307 	mmc->caps |= MMC_CAP_NEEDS_POLL;
1308 	mmc->caps |= MMC_CAP_WAIT_WHILE_BUSY;
1309 
1310 	if (pdata && (pdata->wires == 4 || pdata->wires == 0))
1311 		mmc->caps |= MMC_CAP_4_BIT_DATA;
1312 
1313 	if (pdata && (pdata->wires == 8))
1314 		mmc->caps |= (MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA);
1315 
1316 	id_entry = platform_get_device_id(pdev);
1317 	if (id_entry)
1318 		host->version = id_entry->driver_data;
1319 
1320 	mmc->ops = &mmc_davinci_ops;
1321 	mmc->f_min = 312500;
1322 	mmc->f_max = 25000000;
1323 	if (pdata && pdata->max_freq)
1324 		mmc->f_max = pdata->max_freq;
1325 	if (pdata && pdata->caps)
1326 		mmc->caps |= pdata->caps;
1327 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1328 
1329 	/* With no iommu coalescing pages, each phys_seg is a hw_seg.
1330 	 * Each hw_seg uses one EDMA parameter RAM slot, always one
1331 	 * channel and then usually some linked slots.
1332 	 */
1333 	mmc->max_segs		= MAX_NR_SG;
1334 
1335 	/* EDMA limit per hw segment (one or two MBytes) */
1336 	mmc->max_seg_size	= MAX_CCNT * rw_threshold;
1337 
1338 	/* MMC/SD controller limits for multiblock requests */
1339 	mmc->max_blk_size	= 4095;  /* BLEN is 12 bits */
1340 	mmc->max_blk_count	= 65535; /* NBLK is 16 bits */
1341 	mmc->max_req_size	= mmc->max_blk_size * mmc->max_blk_count;
1342 
1343 	dev_dbg(mmc_dev(host->mmc), "max_segs=%d\n", mmc->max_segs);
1344 	dev_dbg(mmc_dev(host->mmc), "max_blk_size=%d\n", mmc->max_blk_size);
1345 	dev_dbg(mmc_dev(host->mmc), "max_req_size=%d\n", mmc->max_req_size);
1346 	dev_dbg(mmc_dev(host->mmc), "max_seg_size=%d\n", mmc->max_seg_size);
1347 
1348 	platform_set_drvdata(pdev, host);
1349 
1350 	ret = mmc_davinci_cpufreq_register(host);
1351 	if (ret) {
1352 		dev_err(&pdev->dev, "failed to register cpufreq\n");
1353 		goto cpu_freq_fail;
1354 	}
1355 
1356 	ret = mmc_add_host(mmc);
1357 	if (ret < 0)
1358 		goto out;
1359 
1360 	ret = request_irq(irq, mmc_davinci_irq, 0, mmc_hostname(mmc), host);
1361 	if (ret)
1362 		goto out;
1363 
1364 	if (host->sdio_irq >= 0) {
1365 		ret = request_irq(host->sdio_irq, mmc_davinci_sdio_irq, 0,
1366 				  mmc_hostname(mmc), host);
1367 		if (!ret)
1368 			mmc->caps |= MMC_CAP_SDIO_IRQ;
1369 	}
1370 
1371 	rename_region(mem, mmc_hostname(mmc));
1372 
1373 	dev_info(mmc_dev(host->mmc), "Using %s, %d-bit mode\n",
1374 		host->use_dma ? "DMA" : "PIO",
1375 		(mmc->caps & MMC_CAP_4_BIT_DATA) ? 4 : 1);
1376 
1377 	return 0;
1378 
1379 out:
1380 	mmc_davinci_cpufreq_deregister(host);
1381 cpu_freq_fail:
1382 	if (host) {
1383 		davinci_release_dma_channels(host);
1384 
1385 		if (host->clk) {
1386 			clk_disable(host->clk);
1387 			clk_put(host->clk);
1388 		}
1389 
1390 		if (host->base)
1391 			iounmap(host->base);
1392 	}
1393 
1394 	if (mmc)
1395 		mmc_free_host(mmc);
1396 
1397 	if (mem)
1398 		release_resource(mem);
1399 
1400 	dev_dbg(&pdev->dev, "probe err %d\n", ret);
1401 
1402 	return ret;
1403 }
1404 
1405 static int __exit davinci_mmcsd_remove(struct platform_device *pdev)
1406 {
1407 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
1408 
1409 	if (host) {
1410 		mmc_davinci_cpufreq_deregister(host);
1411 
1412 		mmc_remove_host(host->mmc);
1413 		free_irq(host->mmc_irq, host);
1414 		if (host->mmc->caps & MMC_CAP_SDIO_IRQ)
1415 			free_irq(host->sdio_irq, host);
1416 
1417 		davinci_release_dma_channels(host);
1418 
1419 		clk_disable(host->clk);
1420 		clk_put(host->clk);
1421 
1422 		iounmap(host->base);
1423 
1424 		release_resource(host->mem_res);
1425 
1426 		mmc_free_host(host->mmc);
1427 	}
1428 
1429 	return 0;
1430 }
1431 
1432 #ifdef CONFIG_PM
1433 static int davinci_mmcsd_suspend(struct device *dev)
1434 {
1435 	struct platform_device *pdev = to_platform_device(dev);
1436 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
1437 
1438 	writel(0, host->base + DAVINCI_MMCIM);
1439 	mmc_davinci_reset_ctrl(host, 1);
1440 	clk_disable(host->clk);
1441 
1442 	return 0;
1443 }
1444 
1445 static int davinci_mmcsd_resume(struct device *dev)
1446 {
1447 	struct platform_device *pdev = to_platform_device(dev);
1448 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
1449 
1450 	clk_enable(host->clk);
1451 	mmc_davinci_reset_ctrl(host, 0);
1452 
1453 	return 0;
1454 }
1455 
1456 static const struct dev_pm_ops davinci_mmcsd_pm = {
1457 	.suspend        = davinci_mmcsd_suspend,
1458 	.resume         = davinci_mmcsd_resume,
1459 };
1460 
1461 #define davinci_mmcsd_pm_ops (&davinci_mmcsd_pm)
1462 #else
1463 #define davinci_mmcsd_pm_ops NULL
1464 #endif
1465 
1466 static struct platform_driver davinci_mmcsd_driver = {
1467 	.driver		= {
1468 		.name	= "davinci_mmc",
1469 		.owner	= THIS_MODULE,
1470 		.pm	= davinci_mmcsd_pm_ops,
1471 		.of_match_table = davinci_mmc_dt_ids,
1472 	},
1473 	.remove		= __exit_p(davinci_mmcsd_remove),
1474 	.id_table	= davinci_mmc_devtype,
1475 };
1476 
1477 module_platform_driver_probe(davinci_mmcsd_driver, davinci_mmcsd_probe);
1478 
1479 MODULE_AUTHOR("Texas Instruments India");
1480 MODULE_LICENSE("GPL");
1481 MODULE_DESCRIPTION("MMC/SD driver for Davinci MMC controller");
1482 MODULE_ALIAS("platform:davinci_mmc");
1483 
1484