1 /*
2  * Renesas SDHI
3  *
4  * Copyright (C) 2015-17 Renesas Electronics Corporation
5  * Copyright (C) 2016-17 Sang Engineering, Wolfram Sang
6  * Copyright (C) 2016-17 Horms Solutions, Simon Horman
7  * Copyright (C) 2009 Magnus Damm
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  *
13  * Based on "Compaq ASIC3 support":
14  *
15  * Copyright 2001 Compaq Computer Corporation.
16  * Copyright 2004-2005 Phil Blundell
17  * Copyright 2007-2008 OpenedHand Ltd.
18  *
19  * Authors: Phil Blundell <pb@handhelds.org>,
20  *	    Samuel Ortiz <sameo@openedhand.com>
21  *
22  */
23 
24 #include <linux/kernel.h>
25 #include <linux/clk.h>
26 #include <linux/slab.h>
27 #include <linux/module.h>
28 #include <linux/of_device.h>
29 #include <linux/platform_device.h>
30 #include <linux/mmc/host.h>
31 #include <linux/mmc/slot-gpio.h>
32 #include <linux/mfd/tmio.h>
33 #include <linux/sh_dma.h>
34 #include <linux/delay.h>
35 #include <linux/pinctrl/consumer.h>
36 #include <linux/pinctrl/pinctrl-state.h>
37 #include <linux/regulator/consumer.h>
38 
39 #include "renesas_sdhi.h"
40 #include "tmio_mmc.h"
41 
42 #define HOST_MODE		0xe4
43 
44 #define SDHI_VER_GEN2_SDR50	0x490c
45 #define SDHI_VER_RZ_A1		0x820b
46 /* very old datasheets said 0x490c for SDR104, too. They are wrong! */
47 #define SDHI_VER_GEN2_SDR104	0xcb0d
48 #define SDHI_VER_GEN3_SD	0xcc10
49 #define SDHI_VER_GEN3_SDMMC	0xcd10
50 
51 static void renesas_sdhi_sdbuf_width(struct tmio_mmc_host *host, int width)
52 {
53 	u32 val;
54 
55 	/*
56 	 * see also
57 	 *	renesas_sdhi_of_data :: dma_buswidth
58 	 */
59 	switch (sd_ctrl_read16(host, CTL_VERSION)) {
60 	case SDHI_VER_GEN2_SDR50:
61 		val = (width == 32) ? 0x0001 : 0x0000;
62 		break;
63 	case SDHI_VER_GEN2_SDR104:
64 		val = (width == 32) ? 0x0000 : 0x0001;
65 		break;
66 	case SDHI_VER_GEN3_SD:
67 	case SDHI_VER_GEN3_SDMMC:
68 		if (width == 64)
69 			val = 0x0000;
70 		else if (width == 32)
71 			val = 0x0101;
72 		else
73 			val = 0x0001;
74 		break;
75 	default:
76 		/* nothing to do */
77 		return;
78 	}
79 
80 	sd_ctrl_write16(host, HOST_MODE, val);
81 }
82 
83 static int renesas_sdhi_clk_enable(struct tmio_mmc_host *host)
84 {
85 	struct mmc_host *mmc = host->mmc;
86 	struct renesas_sdhi *priv = host_to_priv(host);
87 	int ret = clk_prepare_enable(priv->clk);
88 
89 	if (ret < 0)
90 		return ret;
91 
92 	ret = clk_prepare_enable(priv->clk_cd);
93 	if (ret < 0) {
94 		clk_disable_unprepare(priv->clk);
95 		return ret;
96 	}
97 
98 	/*
99 	 * The clock driver may not know what maximum frequency
100 	 * actually works, so it should be set with the max-frequency
101 	 * property which will already have been read to f_max.  If it
102 	 * was missing, assume the current frequency is the maximum.
103 	 */
104 	if (!mmc->f_max)
105 		mmc->f_max = clk_get_rate(priv->clk);
106 
107 	/*
108 	 * Minimum frequency is the minimum input clock frequency
109 	 * divided by our maximum divider.
110 	 */
111 	mmc->f_min = max(clk_round_rate(priv->clk, 1) / 512, 1L);
112 
113 	/* enable 16bit data access on SDBUF as default */
114 	renesas_sdhi_sdbuf_width(host, 16);
115 
116 	return 0;
117 }
118 
119 static unsigned int renesas_sdhi_clk_update(struct tmio_mmc_host *host,
120 					    unsigned int new_clock)
121 {
122 	struct renesas_sdhi *priv = host_to_priv(host);
123 	unsigned int freq, diff, best_freq = 0, diff_min = ~0;
124 	int i, ret;
125 
126 	/* tested only on R-Car Gen2+ currently; may work for others */
127 	if (!(host->pdata->flags & TMIO_MMC_MIN_RCAR2))
128 		return clk_get_rate(priv->clk);
129 
130 	/*
131 	 * We want the bus clock to be as close as possible to, but no
132 	 * greater than, new_clock.  As we can divide by 1 << i for
133 	 * any i in [0, 9] we want the input clock to be as close as
134 	 * possible, but no greater than, new_clock << i.
135 	 */
136 	for (i = min(9, ilog2(UINT_MAX / new_clock)); i >= 0; i--) {
137 		freq = clk_round_rate(priv->clk, new_clock << i);
138 		if (freq > (new_clock << i)) {
139 			/* Too fast; look for a slightly slower option */
140 			freq = clk_round_rate(priv->clk,
141 					      (new_clock << i) / 4 * 3);
142 			if (freq > (new_clock << i))
143 				continue;
144 		}
145 
146 		diff = new_clock - (freq >> i);
147 		if (diff <= diff_min) {
148 			best_freq = freq;
149 			diff_min = diff;
150 		}
151 	}
152 
153 	ret = clk_set_rate(priv->clk, best_freq);
154 
155 	return ret == 0 ? best_freq : clk_get_rate(priv->clk);
156 }
157 
158 static void renesas_sdhi_clk_disable(struct tmio_mmc_host *host)
159 {
160 	struct renesas_sdhi *priv = host_to_priv(host);
161 
162 	clk_disable_unprepare(priv->clk);
163 	clk_disable_unprepare(priv->clk_cd);
164 }
165 
166 static int renesas_sdhi_card_busy(struct mmc_host *mmc)
167 {
168 	struct tmio_mmc_host *host = mmc_priv(mmc);
169 
170 	return !(sd_ctrl_read16_and_16_as_32(host, CTL_STATUS) &
171 		 TMIO_STAT_DAT0);
172 }
173 
174 static int renesas_sdhi_start_signal_voltage_switch(struct mmc_host *mmc,
175 						    struct mmc_ios *ios)
176 {
177 	struct tmio_mmc_host *host = mmc_priv(mmc);
178 	struct renesas_sdhi *priv = host_to_priv(host);
179 	struct pinctrl_state *pin_state;
180 	int ret;
181 
182 	switch (ios->signal_voltage) {
183 	case MMC_SIGNAL_VOLTAGE_330:
184 		pin_state = priv->pins_default;
185 		break;
186 	case MMC_SIGNAL_VOLTAGE_180:
187 		pin_state = priv->pins_uhs;
188 		break;
189 	default:
190 		return -EINVAL;
191 	}
192 
193 	/*
194 	 * If anything is missing, assume signal voltage is fixed at
195 	 * 3.3V and succeed/fail accordingly.
196 	 */
197 	if (IS_ERR(priv->pinctrl) || IS_ERR(pin_state))
198 		return ios->signal_voltage ==
199 			MMC_SIGNAL_VOLTAGE_330 ? 0 : -EINVAL;
200 
201 	ret = mmc_regulator_set_vqmmc(host->mmc, ios);
202 	if (ret)
203 		return ret;
204 
205 	return pinctrl_select_state(priv->pinctrl, pin_state);
206 }
207 
208 /* SCC registers */
209 #define SH_MOBILE_SDHI_SCC_DTCNTL	0x000
210 #define SH_MOBILE_SDHI_SCC_TAPSET	0x002
211 #define SH_MOBILE_SDHI_SCC_DT2FF	0x004
212 #define SH_MOBILE_SDHI_SCC_CKSEL	0x006
213 #define SH_MOBILE_SDHI_SCC_RVSCNTL	0x008
214 #define SH_MOBILE_SDHI_SCC_RVSREQ	0x00A
215 #define SH_MOBILE_SDHI_SCC_TMPPORT2	0x00E
216 
217 /* Definitions for values the SH_MOBILE_SDHI_SCC_DTCNTL register */
218 #define SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN		BIT(0)
219 #define SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT	16
220 #define SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_MASK	0xff
221 
222 /* Definitions for values the SH_MOBILE_SDHI_SCC_CKSEL register */
223 #define SH_MOBILE_SDHI_SCC_CKSEL_DTSEL		BIT(0)
224 /* Definitions for values the SH_MOBILE_SDHI_SCC_RVSCNTL register */
225 #define SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN	BIT(0)
226 /* Definitions for values the SH_MOBILE_SDHI_SCC_RVSREQ register */
227 #define SH_MOBILE_SDHI_SCC_RVSREQ_RVSERR	BIT(2)
228 /* Definitions for values the SH_MOBILE_SDHI_SCC_TMPPORT2 register */
229 #define SH_MOBILE_SDHI_SCC_TMPPORT2_HS400OSEL	BIT(4)
230 #define SH_MOBILE_SDHI_SCC_TMPPORT2_HS400EN	BIT(31)
231 
232 static inline u32 sd_scc_read32(struct tmio_mmc_host *host,
233 				struct renesas_sdhi *priv, int addr)
234 {
235 	return readl(priv->scc_ctl + (addr << host->bus_shift));
236 }
237 
238 static inline void sd_scc_write32(struct tmio_mmc_host *host,
239 				  struct renesas_sdhi *priv,
240 				  int addr, u32 val)
241 {
242 	writel(val, priv->scc_ctl + (addr << host->bus_shift));
243 }
244 
245 static unsigned int renesas_sdhi_init_tuning(struct tmio_mmc_host *host)
246 {
247 	struct renesas_sdhi *priv;
248 
249 	priv = host_to_priv(host);
250 
251 	/* Initialize SCC */
252 	sd_ctrl_write32_as_16_and_16(host, CTL_STATUS, 0x0);
253 
254 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
255 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
256 
257 	/* set sampling clock selection range */
258 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL,
259 		       SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN |
260 		       0x8 << SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT);
261 
262 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL,
263 		       SH_MOBILE_SDHI_SCC_CKSEL_DTSEL |
264 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL));
265 
266 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
267 		       ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &
268 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
269 
270 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DT2FF, priv->scc_tappos);
271 
272 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
273 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
274 
275 	/* Read TAPNUM */
276 	return (sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL) >>
277 		SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT) &
278 		SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_MASK;
279 }
280 
281 static void renesas_sdhi_prepare_tuning(struct tmio_mmc_host *host,
282 					unsigned long tap)
283 {
284 	struct renesas_sdhi *priv = host_to_priv(host);
285 
286 	/* Set sampling clock position */
287 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET, tap);
288 }
289 
290 static void renesas_sdhi_hs400_complete(struct tmio_mmc_host *host)
291 {
292 	struct renesas_sdhi *priv = host_to_priv(host);
293 
294 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
295 		sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
296 
297 	/* Set HS400 mode */
298 	sd_ctrl_write16(host, CTL_SDIF_MODE, 0x0001 |
299 			sd_ctrl_read16(host, CTL_SDIF_MODE));
300 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TMPPORT2,
301 		       (SH_MOBILE_SDHI_SCC_TMPPORT2_HS400EN |
302 			SH_MOBILE_SDHI_SCC_TMPPORT2_HS400OSEL) |
303 			sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_TMPPORT2));
304 
305 	/* Set the sampling clock selection range of HS400 mode */
306 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL,
307 		       SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN |
308 		       0x4 << SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT);
309 
310 
311 	if (host->pdata->flags & TMIO_MMC_HAVE_4TAP_HS400)
312 		sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET,
313 			       host->tap_set / 2);
314 
315 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL,
316 		       SH_MOBILE_SDHI_SCC_CKSEL_DTSEL |
317 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL));
318 
319 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
320 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
321 }
322 
323 static void renesas_sdhi_reset_scc(struct tmio_mmc_host *host,
324 				   struct renesas_sdhi *priv)
325 {
326 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
327 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
328 
329 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL,
330 		       ~SH_MOBILE_SDHI_SCC_CKSEL_DTSEL &
331 		       sd_scc_read32(host, priv,
332 				     SH_MOBILE_SDHI_SCC_CKSEL));
333 }
334 
335 static void renesas_sdhi_disable_scc(struct tmio_mmc_host *host)
336 {
337 	struct renesas_sdhi *priv = host_to_priv(host);
338 
339 	renesas_sdhi_reset_scc(host, priv);
340 
341 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL,
342 		       ~SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN &
343 		       sd_scc_read32(host, priv,
344 				     SH_MOBILE_SDHI_SCC_DTCNTL));
345 
346 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
347 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
348 }
349 
350 static void renesas_sdhi_reset_hs400_mode(struct tmio_mmc_host *host,
351 					  struct renesas_sdhi *priv)
352 {
353 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
354 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
355 
356 	/* Reset HS400 mode */
357 	sd_ctrl_write16(host, CTL_SDIF_MODE, ~0x0001 &
358 			sd_ctrl_read16(host, CTL_SDIF_MODE));
359 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TMPPORT2,
360 		       ~(SH_MOBILE_SDHI_SCC_TMPPORT2_HS400EN |
361 			 SH_MOBILE_SDHI_SCC_TMPPORT2_HS400OSEL) &
362 			sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_TMPPORT2));
363 
364 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
365 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
366 }
367 
368 static void renesas_sdhi_prepare_hs400_tuning(struct tmio_mmc_host *host)
369 {
370 	renesas_sdhi_reset_hs400_mode(host, host_to_priv(host));
371 }
372 
373 #define SH_MOBILE_SDHI_MAX_TAP 3
374 
375 static int renesas_sdhi_select_tuning(struct tmio_mmc_host *host)
376 {
377 	struct renesas_sdhi *priv = host_to_priv(host);
378 	unsigned long tap_cnt;  /* counter of tuning success */
379 	unsigned long tap_start;/* start position of tuning success */
380 	unsigned long tap_end;  /* end position of tuning success */
381 	unsigned long ntap;     /* temporary counter of tuning success */
382 	unsigned long i;
383 
384 	/* Clear SCC_RVSREQ */
385 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0);
386 
387 	/*
388 	 * When tuning CMD19 is issued twice for each tap, merge the
389 	 * result requiring the tap to be good in both runs before
390 	 * considering it for tuning selection.
391 	 */
392 	for (i = 0; i < host->tap_num * 2; i++) {
393 		int offset = host->tap_num * (i < host->tap_num ? 1 : -1);
394 
395 		if (!test_bit(i, host->taps))
396 			clear_bit(i + offset, host->taps);
397 	}
398 
399 	/*
400 	 * Find the longest consecutive run of successful probes.  If that
401 	 * is more than SH_MOBILE_SDHI_MAX_TAP probes long then use the
402 	 * center index as the tap.
403 	 */
404 	tap_cnt = 0;
405 	ntap = 0;
406 	tap_start = 0;
407 	tap_end = 0;
408 	for (i = 0; i < host->tap_num * 2; i++) {
409 		if (test_bit(i, host->taps)) {
410 			ntap++;
411 		} else {
412 			if (ntap > tap_cnt) {
413 				tap_start = i - ntap;
414 				tap_end = i - 1;
415 				tap_cnt = ntap;
416 			}
417 			ntap = 0;
418 		}
419 	}
420 
421 	if (ntap > tap_cnt) {
422 		tap_start = i - ntap;
423 		tap_end = i - 1;
424 		tap_cnt = ntap;
425 	}
426 
427 	if (tap_cnt >= SH_MOBILE_SDHI_MAX_TAP)
428 		host->tap_set = (tap_start + tap_end) / 2 % host->tap_num;
429 	else
430 		return -EIO;
431 
432 	/* Set SCC */
433 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET, host->tap_set);
434 
435 	/* Enable auto re-tuning */
436 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
437 		       SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN |
438 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
439 
440 	return 0;
441 }
442 
443 static bool renesas_sdhi_check_scc_error(struct tmio_mmc_host *host)
444 {
445 	struct renesas_sdhi *priv = host_to_priv(host);
446 
447 	/* Check SCC error */
448 	if (sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL) &
449 	    SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &&
450 	    sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ) &
451 	    SH_MOBILE_SDHI_SCC_RVSREQ_RVSERR) {
452 		/* Clear SCC error */
453 		sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0);
454 		return true;
455 	}
456 
457 	return false;
458 }
459 
460 static void renesas_sdhi_hw_reset(struct tmio_mmc_host *host)
461 {
462 	struct renesas_sdhi *priv;
463 
464 	priv = host_to_priv(host);
465 
466 	renesas_sdhi_reset_scc(host, priv);
467 	renesas_sdhi_reset_hs400_mode(host, priv);
468 
469 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
470 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
471 
472 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
473 		       ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &
474 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
475 
476 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
477 		       ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &
478 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
479 }
480 
481 static int renesas_sdhi_wait_idle(struct tmio_mmc_host *host, u32 bit)
482 {
483 	int timeout = 1000;
484 	/* CBSY is set when busy, SCLKDIVEN is cleared when busy */
485 	u32 wait_state = (bit == TMIO_STAT_CMD_BUSY ? TMIO_STAT_CMD_BUSY : 0);
486 
487 	while (--timeout && (sd_ctrl_read16_and_16_as_32(host, CTL_STATUS)
488 			      & bit) == wait_state)
489 		udelay(1);
490 
491 	if (!timeout) {
492 		dev_warn(&host->pdev->dev, "timeout waiting for SD bus idle\n");
493 		return -EBUSY;
494 	}
495 
496 	return 0;
497 }
498 
499 static int renesas_sdhi_write16_hook(struct tmio_mmc_host *host, int addr)
500 {
501 	u32 bit = TMIO_STAT_SCLKDIVEN;
502 
503 	switch (addr) {
504 	case CTL_SD_CMD:
505 	case CTL_STOP_INTERNAL_ACTION:
506 	case CTL_XFER_BLK_COUNT:
507 	case CTL_SD_XFER_LEN:
508 	case CTL_SD_MEM_CARD_OPT:
509 	case CTL_TRANSACTION_CTL:
510 	case CTL_DMA_ENABLE:
511 	case HOST_MODE:
512 		if (host->pdata->flags & TMIO_MMC_HAVE_CBSY)
513 			bit = TMIO_STAT_CMD_BUSY;
514 		/* fallthrough */
515 	case CTL_SD_CARD_CLK_CTL:
516 		return renesas_sdhi_wait_idle(host, bit);
517 	}
518 
519 	return 0;
520 }
521 
522 static int renesas_sdhi_multi_io_quirk(struct mmc_card *card,
523 				       unsigned int direction, int blk_size)
524 {
525 	/*
526 	 * In Renesas controllers, when performing a
527 	 * multiple block read of one or two blocks,
528 	 * depending on the timing with which the
529 	 * response register is read, the response
530 	 * value may not be read properly.
531 	 * Use single block read for this HW bug
532 	 */
533 	if ((direction == MMC_DATA_READ) &&
534 	    blk_size == 2)
535 		return 1;
536 
537 	return blk_size;
538 }
539 
540 static void renesas_sdhi_enable_dma(struct tmio_mmc_host *host, bool enable)
541 {
542 	/* Iff regs are 8 byte apart, sdbuf is 64 bit. Otherwise always 32. */
543 	int width = (host->bus_shift == 2) ? 64 : 32;
544 
545 	sd_ctrl_write16(host, CTL_DMA_ENABLE, enable ? DMA_ENABLE_DMASDRW : 0);
546 	renesas_sdhi_sdbuf_width(host, enable ? width : 16);
547 }
548 
549 int renesas_sdhi_probe(struct platform_device *pdev,
550 		       const struct tmio_mmc_dma_ops *dma_ops)
551 {
552 	struct tmio_mmc_data *mmd = pdev->dev.platform_data;
553 	const struct renesas_sdhi_of_data *of_data;
554 	struct tmio_mmc_data *mmc_data;
555 	struct tmio_mmc_dma *dma_priv;
556 	struct tmio_mmc_host *host;
557 	struct renesas_sdhi *priv;
558 	struct resource *res;
559 	int irq, ret, i;
560 
561 	of_data = of_device_get_match_data(&pdev->dev);
562 
563 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
564 	if (!res)
565 		return -EINVAL;
566 
567 	priv = devm_kzalloc(&pdev->dev, sizeof(struct renesas_sdhi),
568 			    GFP_KERNEL);
569 	if (!priv)
570 		return -ENOMEM;
571 
572 	mmc_data = &priv->mmc_data;
573 	dma_priv = &priv->dma_priv;
574 
575 	priv->clk = devm_clk_get(&pdev->dev, NULL);
576 	if (IS_ERR(priv->clk)) {
577 		ret = PTR_ERR(priv->clk);
578 		dev_err(&pdev->dev, "cannot get clock: %d\n", ret);
579 		return ret;
580 	}
581 
582 	/*
583 	 * Some controllers provide a 2nd clock just to run the internal card
584 	 * detection logic. Unfortunately, the existing driver architecture does
585 	 * not support a separation of clocks for runtime PM usage. When
586 	 * native hotplug is used, the tmio driver assumes that the core
587 	 * must continue to run for card detect to stay active, so we cannot
588 	 * disable it.
589 	 * Additionally, it is prohibited to supply a clock to the core but not
590 	 * to the card detect circuit. That leaves us with if separate clocks
591 	 * are presented, we must treat them both as virtually 1 clock.
592 	 */
593 	priv->clk_cd = devm_clk_get(&pdev->dev, "cd");
594 	if (IS_ERR(priv->clk_cd))
595 		priv->clk_cd = NULL;
596 
597 	priv->pinctrl = devm_pinctrl_get(&pdev->dev);
598 	if (!IS_ERR(priv->pinctrl)) {
599 		priv->pins_default = pinctrl_lookup_state(priv->pinctrl,
600 						PINCTRL_STATE_DEFAULT);
601 		priv->pins_uhs = pinctrl_lookup_state(priv->pinctrl,
602 						"state_uhs");
603 	}
604 
605 	host = tmio_mmc_host_alloc(pdev, mmc_data);
606 	if (IS_ERR(host))
607 		return PTR_ERR(host);
608 
609 	if (of_data) {
610 		mmc_data->flags |= of_data->tmio_flags;
611 		mmc_data->ocr_mask = of_data->tmio_ocr_mask;
612 		mmc_data->capabilities |= of_data->capabilities;
613 		mmc_data->capabilities2 |= of_data->capabilities2;
614 		mmc_data->dma_rx_offset = of_data->dma_rx_offset;
615 		mmc_data->max_blk_count = of_data->max_blk_count;
616 		mmc_data->max_segs = of_data->max_segs;
617 		dma_priv->dma_buswidth = of_data->dma_buswidth;
618 		host->bus_shift = of_data->bus_shift;
619 	}
620 
621 	host->write16_hook	= renesas_sdhi_write16_hook;
622 	host->clk_enable	= renesas_sdhi_clk_enable;
623 	host->clk_update	= renesas_sdhi_clk_update;
624 	host->clk_disable	= renesas_sdhi_clk_disable;
625 	host->multi_io_quirk	= renesas_sdhi_multi_io_quirk;
626 	host->dma_ops		= dma_ops;
627 
628 	/* For some SoC, we disable internal WP. GPIO may override this */
629 	if (mmc_can_gpio_ro(host->mmc))
630 		mmc_data->capabilities2 &= ~MMC_CAP2_NO_WRITE_PROTECT;
631 
632 	/* SDR speeds are only available on Gen2+ */
633 	if (mmc_data->flags & TMIO_MMC_MIN_RCAR2) {
634 		/* card_busy caused issues on r8a73a4 (pre-Gen2) CD-less SDHI */
635 		host->ops.card_busy = renesas_sdhi_card_busy;
636 		host->ops.start_signal_voltage_switch =
637 			renesas_sdhi_start_signal_voltage_switch;
638 	}
639 
640 	/* Orginally registers were 16 bit apart, could be 32 or 64 nowadays */
641 	if (!host->bus_shift && resource_size(res) > 0x100) /* old way to determine the shift */
642 		host->bus_shift = 1;
643 
644 	if (mmd)
645 		*mmc_data = *mmd;
646 
647 	dma_priv->filter = shdma_chan_filter;
648 	dma_priv->enable = renesas_sdhi_enable_dma;
649 
650 	mmc_data->alignment_shift = 1; /* 2-byte alignment */
651 	mmc_data->capabilities |= MMC_CAP_MMC_HIGHSPEED;
652 
653 	/*
654 	 * All SDHI blocks support 2-byte and larger block sizes in 4-bit
655 	 * bus width mode.
656 	 */
657 	mmc_data->flags |= TMIO_MMC_BLKSZ_2BYTES;
658 
659 	/*
660 	 * All SDHI blocks support SDIO IRQ signalling.
661 	 */
662 	mmc_data->flags |= TMIO_MMC_SDIO_IRQ;
663 
664 	/* All SDHI have CMD12 control bit */
665 	mmc_data->flags |= TMIO_MMC_HAVE_CMD12_CTRL;
666 
667 	/* All SDHI have SDIO status bits which must be 1 */
668 	mmc_data->flags |= TMIO_MMC_SDIO_STATUS_SETBITS;
669 
670 	ret = renesas_sdhi_clk_enable(host);
671 	if (ret)
672 		goto efree;
673 
674 	ret = tmio_mmc_host_probe(host);
675 	if (ret < 0)
676 		goto edisclk;
677 
678 	/* One Gen2 SDHI incarnation does NOT have a CBSY bit */
679 	if (sd_ctrl_read16(host, CTL_VERSION) == SDHI_VER_GEN2_SDR50)
680 		mmc_data->flags &= ~TMIO_MMC_HAVE_CBSY;
681 
682 	/* Enable tuning iff we have an SCC and a supported mode */
683 	if (of_data && of_data->scc_offset &&
684 	    (host->mmc->caps & MMC_CAP_UHS_SDR104 ||
685 	     host->mmc->caps2 & (MMC_CAP2_HS200_1_8V_SDR |
686 				 MMC_CAP2_HS400_1_8V))) {
687 		const struct renesas_sdhi_scc *taps = of_data->taps;
688 		bool hit = false;
689 
690 		host->mmc->caps |= MMC_CAP_HW_RESET;
691 
692 		for (i = 0; i < of_data->taps_num; i++) {
693 			if (taps[i].clk_rate == 0 ||
694 			    taps[i].clk_rate == host->mmc->f_max) {
695 				priv->scc_tappos = taps->tap;
696 				hit = true;
697 				break;
698 			}
699 		}
700 
701 		if (!hit)
702 			dev_warn(&host->pdev->dev, "Unknown clock rate for SDR104\n");
703 
704 		priv->scc_ctl = host->ctl + of_data->scc_offset;
705 		host->init_tuning = renesas_sdhi_init_tuning;
706 		host->prepare_tuning = renesas_sdhi_prepare_tuning;
707 		host->select_tuning = renesas_sdhi_select_tuning;
708 		host->check_scc_error = renesas_sdhi_check_scc_error;
709 		host->hw_reset = renesas_sdhi_hw_reset;
710 		host->prepare_hs400_tuning =
711 			renesas_sdhi_prepare_hs400_tuning;
712 		host->hs400_downgrade = renesas_sdhi_disable_scc;
713 		host->hs400_complete = renesas_sdhi_hs400_complete;
714 	}
715 
716 	i = 0;
717 	while (1) {
718 		irq = platform_get_irq(pdev, i);
719 		if (irq < 0)
720 			break;
721 		i++;
722 		ret = devm_request_irq(&pdev->dev, irq, tmio_mmc_irq, 0,
723 				       dev_name(&pdev->dev), host);
724 		if (ret)
725 			goto eirq;
726 	}
727 
728 	/* There must be at least one IRQ source */
729 	if (!i) {
730 		ret = irq;
731 		goto eirq;
732 	}
733 
734 	dev_info(&pdev->dev, "%s base at 0x%08lx max clock rate %u MHz\n",
735 		 mmc_hostname(host->mmc), (unsigned long)
736 		 (platform_get_resource(pdev, IORESOURCE_MEM, 0)->start),
737 		 host->mmc->f_max / 1000000);
738 
739 	return ret;
740 
741 eirq:
742 	tmio_mmc_host_remove(host);
743 edisclk:
744 	renesas_sdhi_clk_disable(host);
745 efree:
746 	tmio_mmc_host_free(host);
747 
748 	return ret;
749 }
750 EXPORT_SYMBOL_GPL(renesas_sdhi_probe);
751 
752 int renesas_sdhi_remove(struct platform_device *pdev)
753 {
754 	struct tmio_mmc_host *host = platform_get_drvdata(pdev);
755 
756 	tmio_mmc_host_remove(host);
757 	renesas_sdhi_clk_disable(host);
758 
759 	return 0;
760 }
761 EXPORT_SYMBOL_GPL(renesas_sdhi_remove);
762 
763 MODULE_LICENSE("GPL v2");
764