1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Renesas SDHI
4  *
5  * Copyright (C) 2015-19 Renesas Electronics Corporation
6  * Copyright (C) 2016-19 Sang Engineering, Wolfram Sang
7  * Copyright (C) 2016-17 Horms Solutions, Simon Horman
8  * Copyright (C) 2009 Magnus Damm
9  *
10  * Based on "Compaq ASIC3 support":
11  *
12  * Copyright 2001 Compaq Computer Corporation.
13  * Copyright 2004-2005 Phil Blundell
14  * Copyright 2007-2008 OpenedHand Ltd.
15  *
16  * Authors: Phil Blundell <pb@handhelds.org>,
17  *	    Samuel Ortiz <sameo@openedhand.com>
18  *
19  */
20 
21 #include <linux/kernel.h>
22 #include <linux/clk.h>
23 #include <linux/slab.h>
24 #include <linux/module.h>
25 #include <linux/of_device.h>
26 #include <linux/platform_device.h>
27 #include <linux/mmc/host.h>
28 #include <linux/mmc/slot-gpio.h>
29 #include <linux/mfd/tmio.h>
30 #include <linux/sh_dma.h>
31 #include <linux/delay.h>
32 #include <linux/pinctrl/consumer.h>
33 #include <linux/pinctrl/pinctrl-state.h>
34 #include <linux/regulator/consumer.h>
35 #include <linux/sys_soc.h>
36 
37 #include "renesas_sdhi.h"
38 #include "tmio_mmc.h"
39 
40 #define HOST_MODE		0xe4
41 
42 #define SDHI_VER_GEN2_SDR50	0x490c
43 #define SDHI_VER_RZ_A1		0x820b
44 /* very old datasheets said 0x490c for SDR104, too. They are wrong! */
45 #define SDHI_VER_GEN2_SDR104	0xcb0d
46 #define SDHI_VER_GEN3_SD	0xcc10
47 #define SDHI_VER_GEN3_SDMMC	0xcd10
48 
49 static void renesas_sdhi_sdbuf_width(struct tmio_mmc_host *host, int width)
50 {
51 	u32 val;
52 
53 	/*
54 	 * see also
55 	 *	renesas_sdhi_of_data :: dma_buswidth
56 	 */
57 	switch (sd_ctrl_read16(host, CTL_VERSION)) {
58 	case SDHI_VER_GEN2_SDR50:
59 		val = (width == 32) ? 0x0001 : 0x0000;
60 		break;
61 	case SDHI_VER_GEN2_SDR104:
62 		val = (width == 32) ? 0x0000 : 0x0001;
63 		break;
64 	case SDHI_VER_GEN3_SD:
65 	case SDHI_VER_GEN3_SDMMC:
66 		if (width == 64)
67 			val = 0x0000;
68 		else if (width == 32)
69 			val = 0x0101;
70 		else
71 			val = 0x0001;
72 		break;
73 	default:
74 		/* nothing to do */
75 		return;
76 	}
77 
78 	sd_ctrl_write16(host, HOST_MODE, val);
79 }
80 
81 static int renesas_sdhi_clk_enable(struct tmio_mmc_host *host)
82 {
83 	struct mmc_host *mmc = host->mmc;
84 	struct renesas_sdhi *priv = host_to_priv(host);
85 	int ret = clk_prepare_enable(priv->clk);
86 
87 	if (ret < 0)
88 		return ret;
89 
90 	ret = clk_prepare_enable(priv->clk_cd);
91 	if (ret < 0) {
92 		clk_disable_unprepare(priv->clk);
93 		return ret;
94 	}
95 
96 	/*
97 	 * The clock driver may not know what maximum frequency
98 	 * actually works, so it should be set with the max-frequency
99 	 * property which will already have been read to f_max.  If it
100 	 * was missing, assume the current frequency is the maximum.
101 	 */
102 	if (!mmc->f_max)
103 		mmc->f_max = clk_get_rate(priv->clk);
104 
105 	/*
106 	 * Minimum frequency is the minimum input clock frequency
107 	 * divided by our maximum divider.
108 	 */
109 	mmc->f_min = max(clk_round_rate(priv->clk, 1) / 512, 1L);
110 
111 	/* enable 16bit data access on SDBUF as default */
112 	renesas_sdhi_sdbuf_width(host, 16);
113 
114 	return 0;
115 }
116 
117 static unsigned int renesas_sdhi_clk_update(struct tmio_mmc_host *host,
118 					    unsigned int new_clock)
119 {
120 	struct renesas_sdhi *priv = host_to_priv(host);
121 	unsigned int freq, diff, best_freq = 0, diff_min = ~0;
122 	int i;
123 
124 	/* tested only on R-Car Gen2+ currently; may work for others */
125 	if (!(host->pdata->flags & TMIO_MMC_MIN_RCAR2))
126 		return clk_get_rate(priv->clk);
127 
128 	/*
129 	 * We want the bus clock to be as close as possible to, but no
130 	 * greater than, new_clock.  As we can divide by 1 << i for
131 	 * any i in [0, 9] we want the input clock to be as close as
132 	 * possible, but no greater than, new_clock << i.
133 	 */
134 	for (i = min(9, ilog2(UINT_MAX / new_clock)); i >= 0; i--) {
135 		freq = clk_round_rate(priv->clk, new_clock << i);
136 		if (freq > (new_clock << i)) {
137 			/* Too fast; look for a slightly slower option */
138 			freq = clk_round_rate(priv->clk,
139 					      (new_clock << i) / 4 * 3);
140 			if (freq > (new_clock << i))
141 				continue;
142 		}
143 
144 		diff = new_clock - (freq >> i);
145 		if (diff <= diff_min) {
146 			best_freq = freq;
147 			diff_min = diff;
148 		}
149 	}
150 
151 	clk_set_rate(priv->clk, best_freq);
152 
153 	return clk_get_rate(priv->clk);
154 }
155 
156 static void renesas_sdhi_set_clock(struct tmio_mmc_host *host,
157 				   unsigned int new_clock)
158 {
159 	u32 clk = 0, clock;
160 
161 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
162 		sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
163 
164 	if (new_clock == 0) {
165 		host->mmc->actual_clock = 0;
166 		goto out;
167 	}
168 
169 	host->mmc->actual_clock = renesas_sdhi_clk_update(host, new_clock);
170 	clock = host->mmc->actual_clock / 512;
171 
172 	for (clk = 0x80000080; new_clock >= (clock << 1); clk >>= 1)
173 		clock <<= 1;
174 
175 	/* 1/1 clock is option */
176 	if ((host->pdata->flags & TMIO_MMC_CLK_ACTUAL) && ((clk >> 22) & 0x1)) {
177 		if (!(host->mmc->ios.timing == MMC_TIMING_MMC_HS400))
178 			clk |= 0xff;
179 		else
180 			clk &= ~0xff;
181 	}
182 
183 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, clk & CLK_CTL_DIV_MASK);
184 	if (!(host->pdata->flags & TMIO_MMC_MIN_RCAR2))
185 		usleep_range(10000, 11000);
186 
187 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
188 		sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
189 
190 out:
191 	/* HW engineers overrode docs: no sleep needed on R-Car2+ */
192 	if (!(host->pdata->flags & TMIO_MMC_MIN_RCAR2))
193 		usleep_range(10000, 11000);
194 }
195 
196 static void renesas_sdhi_clk_disable(struct tmio_mmc_host *host)
197 {
198 	struct renesas_sdhi *priv = host_to_priv(host);
199 
200 	clk_disable_unprepare(priv->clk);
201 	clk_disable_unprepare(priv->clk_cd);
202 }
203 
204 static int renesas_sdhi_card_busy(struct mmc_host *mmc)
205 {
206 	struct tmio_mmc_host *host = mmc_priv(mmc);
207 
208 	return !(sd_ctrl_read16_and_16_as_32(host, CTL_STATUS) &
209 		 TMIO_STAT_DAT0);
210 }
211 
212 static int renesas_sdhi_start_signal_voltage_switch(struct mmc_host *mmc,
213 						    struct mmc_ios *ios)
214 {
215 	struct tmio_mmc_host *host = mmc_priv(mmc);
216 	struct renesas_sdhi *priv = host_to_priv(host);
217 	struct pinctrl_state *pin_state;
218 	int ret;
219 
220 	switch (ios->signal_voltage) {
221 	case MMC_SIGNAL_VOLTAGE_330:
222 		pin_state = priv->pins_default;
223 		break;
224 	case MMC_SIGNAL_VOLTAGE_180:
225 		pin_state = priv->pins_uhs;
226 		break;
227 	default:
228 		return -EINVAL;
229 	}
230 
231 	/*
232 	 * If anything is missing, assume signal voltage is fixed at
233 	 * 3.3V and succeed/fail accordingly.
234 	 */
235 	if (IS_ERR(priv->pinctrl) || IS_ERR(pin_state))
236 		return ios->signal_voltage ==
237 			MMC_SIGNAL_VOLTAGE_330 ? 0 : -EINVAL;
238 
239 	ret = mmc_regulator_set_vqmmc(host->mmc, ios);
240 	if (ret)
241 		return ret;
242 
243 	return pinctrl_select_state(priv->pinctrl, pin_state);
244 }
245 
246 /* SCC registers */
247 #define SH_MOBILE_SDHI_SCC_DTCNTL	0x000
248 #define SH_MOBILE_SDHI_SCC_TAPSET	0x002
249 #define SH_MOBILE_SDHI_SCC_DT2FF	0x004
250 #define SH_MOBILE_SDHI_SCC_CKSEL	0x006
251 #define SH_MOBILE_SDHI_SCC_RVSCNTL	0x008
252 #define SH_MOBILE_SDHI_SCC_RVSREQ	0x00A
253 #define SH_MOBILE_SDHI_SCC_TMPPORT2	0x00E
254 
255 /* Definitions for values the SH_MOBILE_SDHI_SCC_DTCNTL register */
256 #define SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN		BIT(0)
257 #define SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT	16
258 #define SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_MASK	0xff
259 
260 /* Definitions for values the SH_MOBILE_SDHI_SCC_CKSEL register */
261 #define SH_MOBILE_SDHI_SCC_CKSEL_DTSEL		BIT(0)
262 /* Definitions for values the SH_MOBILE_SDHI_SCC_RVSCNTL register */
263 #define SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN	BIT(0)
264 /* Definitions for values the SH_MOBILE_SDHI_SCC_RVSREQ register */
265 #define SH_MOBILE_SDHI_SCC_RVSREQ_RVSERR	BIT(2)
266 /* Definitions for values the SH_MOBILE_SDHI_SCC_TMPPORT2 register */
267 #define SH_MOBILE_SDHI_SCC_TMPPORT2_HS400OSEL	BIT(4)
268 #define SH_MOBILE_SDHI_SCC_TMPPORT2_HS400EN	BIT(31)
269 
270 static inline u32 sd_scc_read32(struct tmio_mmc_host *host,
271 				struct renesas_sdhi *priv, int addr)
272 {
273 	return readl(priv->scc_ctl + (addr << host->bus_shift));
274 }
275 
276 static inline void sd_scc_write32(struct tmio_mmc_host *host,
277 				  struct renesas_sdhi *priv,
278 				  int addr, u32 val)
279 {
280 	writel(val, priv->scc_ctl + (addr << host->bus_shift));
281 }
282 
283 static unsigned int renesas_sdhi_init_tuning(struct tmio_mmc_host *host)
284 {
285 	struct renesas_sdhi *priv;
286 
287 	priv = host_to_priv(host);
288 
289 	/* Initialize SCC */
290 	sd_ctrl_write32_as_16_and_16(host, CTL_STATUS, 0x0);
291 
292 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
293 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
294 
295 	/* set sampling clock selection range */
296 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL,
297 		       SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN |
298 		       0x8 << SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT);
299 
300 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL,
301 		       SH_MOBILE_SDHI_SCC_CKSEL_DTSEL |
302 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL));
303 
304 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
305 		       ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &
306 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
307 
308 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DT2FF, priv->scc_tappos);
309 
310 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
311 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
312 
313 	/* Read TAPNUM */
314 	return (sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL) >>
315 		SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT) &
316 		SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_MASK;
317 }
318 
319 static void renesas_sdhi_prepare_tuning(struct tmio_mmc_host *host,
320 					unsigned long tap)
321 {
322 	struct renesas_sdhi *priv = host_to_priv(host);
323 
324 	/* Set sampling clock position */
325 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET, tap);
326 }
327 
328 static void renesas_sdhi_hs400_complete(struct tmio_mmc_host *host)
329 {
330 	struct renesas_sdhi *priv = host_to_priv(host);
331 
332 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
333 		sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
334 
335 	/* Set HS400 mode */
336 	sd_ctrl_write16(host, CTL_SDIF_MODE, 0x0001 |
337 			sd_ctrl_read16(host, CTL_SDIF_MODE));
338 
339 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DT2FF,
340 		       priv->scc_tappos_hs400);
341 
342 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TMPPORT2,
343 		       (SH_MOBILE_SDHI_SCC_TMPPORT2_HS400EN |
344 			SH_MOBILE_SDHI_SCC_TMPPORT2_HS400OSEL) |
345 			sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_TMPPORT2));
346 
347 	/* Set the sampling clock selection range of HS400 mode */
348 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL,
349 		       SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN |
350 		       0x4 << SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT);
351 
352 
353 	if (priv->quirks && priv->quirks->hs400_4taps)
354 		sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET,
355 			       host->tap_set / 2);
356 
357 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL,
358 		       SH_MOBILE_SDHI_SCC_CKSEL_DTSEL |
359 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL));
360 
361 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
362 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
363 }
364 
365 static void renesas_sdhi_reset_scc(struct tmio_mmc_host *host,
366 				   struct renesas_sdhi *priv)
367 {
368 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
369 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
370 
371 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL,
372 		       ~SH_MOBILE_SDHI_SCC_CKSEL_DTSEL &
373 		       sd_scc_read32(host, priv,
374 				     SH_MOBILE_SDHI_SCC_CKSEL));
375 }
376 
377 static void renesas_sdhi_disable_scc(struct tmio_mmc_host *host)
378 {
379 	struct renesas_sdhi *priv = host_to_priv(host);
380 
381 	renesas_sdhi_reset_scc(host, priv);
382 
383 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL,
384 		       ~SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN &
385 		       sd_scc_read32(host, priv,
386 				     SH_MOBILE_SDHI_SCC_DTCNTL));
387 
388 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
389 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
390 }
391 
392 static void renesas_sdhi_reset_hs400_mode(struct tmio_mmc_host *host,
393 					  struct renesas_sdhi *priv)
394 {
395 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
396 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
397 
398 	/* Reset HS400 mode */
399 	sd_ctrl_write16(host, CTL_SDIF_MODE, ~0x0001 &
400 			sd_ctrl_read16(host, CTL_SDIF_MODE));
401 
402 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DT2FF, priv->scc_tappos);
403 
404 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TMPPORT2,
405 		       ~(SH_MOBILE_SDHI_SCC_TMPPORT2_HS400EN |
406 			 SH_MOBILE_SDHI_SCC_TMPPORT2_HS400OSEL) &
407 			sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_TMPPORT2));
408 
409 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
410 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
411 }
412 
413 static void renesas_sdhi_prepare_hs400_tuning(struct tmio_mmc_host *host)
414 {
415 	renesas_sdhi_reset_hs400_mode(host, host_to_priv(host));
416 }
417 
418 #define SH_MOBILE_SDHI_MAX_TAP 3
419 
420 static int renesas_sdhi_select_tuning(struct tmio_mmc_host *host)
421 {
422 	struct renesas_sdhi *priv = host_to_priv(host);
423 	unsigned long tap_cnt;  /* counter of tuning success */
424 	unsigned long tap_start;/* start position of tuning success */
425 	unsigned long tap_end;  /* end position of tuning success */
426 	unsigned long ntap;     /* temporary counter of tuning success */
427 	unsigned long i;
428 
429 	/* Clear SCC_RVSREQ */
430 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0);
431 
432 	/*
433 	 * When tuning CMD19 is issued twice for each tap, merge the
434 	 * result requiring the tap to be good in both runs before
435 	 * considering it for tuning selection.
436 	 */
437 	for (i = 0; i < host->tap_num * 2; i++) {
438 		int offset = host->tap_num * (i < host->tap_num ? 1 : -1);
439 
440 		if (!test_bit(i, host->taps))
441 			clear_bit(i + offset, host->taps);
442 	}
443 
444 	/*
445 	 * Find the longest consecutive run of successful probes.  If that
446 	 * is more than SH_MOBILE_SDHI_MAX_TAP probes long then use the
447 	 * center index as the tap.
448 	 */
449 	tap_cnt = 0;
450 	ntap = 0;
451 	tap_start = 0;
452 	tap_end = 0;
453 	for (i = 0; i < host->tap_num * 2; i++) {
454 		if (test_bit(i, host->taps)) {
455 			ntap++;
456 		} else {
457 			if (ntap > tap_cnt) {
458 				tap_start = i - ntap;
459 				tap_end = i - 1;
460 				tap_cnt = ntap;
461 			}
462 			ntap = 0;
463 		}
464 	}
465 
466 	if (ntap > tap_cnt) {
467 		tap_start = i - ntap;
468 		tap_end = i - 1;
469 		tap_cnt = ntap;
470 	}
471 
472 	if (tap_cnt >= SH_MOBILE_SDHI_MAX_TAP)
473 		host->tap_set = (tap_start + tap_end) / 2 % host->tap_num;
474 	else
475 		return -EIO;
476 
477 	/* Set SCC */
478 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET, host->tap_set);
479 
480 	/* Enable auto re-tuning */
481 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
482 		       SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN |
483 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
484 
485 	return 0;
486 }
487 
488 static bool renesas_sdhi_check_scc_error(struct tmio_mmc_host *host)
489 {
490 	struct renesas_sdhi *priv = host_to_priv(host);
491 	bool use_4tap = priv->quirks && priv->quirks->hs400_4taps;
492 
493 	/*
494 	 * Skip checking SCC errors when running on 4 taps in HS400 mode as
495 	 * any retuning would still result in the same 4 taps being used.
496 	 */
497 	if (!(host->mmc->ios.timing == MMC_TIMING_UHS_SDR104) &&
498 	    !(host->mmc->ios.timing == MMC_TIMING_MMC_HS200) &&
499 	    !(host->mmc->ios.timing == MMC_TIMING_MMC_HS400 && !use_4tap))
500 		return false;
501 
502 	if (mmc_doing_retune(host->mmc))
503 		return false;
504 
505 	/* Check SCC error */
506 	if (sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL) &
507 	    SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &&
508 	    sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ) &
509 	    SH_MOBILE_SDHI_SCC_RVSREQ_RVSERR) {
510 		/* Clear SCC error */
511 		sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0);
512 		return true;
513 	}
514 
515 	return false;
516 }
517 
518 static void renesas_sdhi_hw_reset(struct tmio_mmc_host *host)
519 {
520 	struct renesas_sdhi *priv;
521 
522 	priv = host_to_priv(host);
523 
524 	renesas_sdhi_reset_scc(host, priv);
525 	renesas_sdhi_reset_hs400_mode(host, priv);
526 
527 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
528 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
529 
530 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
531 		       ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &
532 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
533 
534 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
535 		       ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &
536 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
537 
538 	if (host->pdata->flags & TMIO_MMC_MIN_RCAR2)
539 		sd_ctrl_write32_as_16_and_16(host, CTL_IRQ_MASK,
540 					     TMIO_MASK_INIT_RCAR2);
541 }
542 
543 static int renesas_sdhi_wait_idle(struct tmio_mmc_host *host, u32 bit)
544 {
545 	int timeout = 1000;
546 	/* CBSY is set when busy, SCLKDIVEN is cleared when busy */
547 	u32 wait_state = (bit == TMIO_STAT_CMD_BUSY ? TMIO_STAT_CMD_BUSY : 0);
548 
549 	while (--timeout && (sd_ctrl_read16_and_16_as_32(host, CTL_STATUS)
550 			      & bit) == wait_state)
551 		udelay(1);
552 
553 	if (!timeout) {
554 		dev_warn(&host->pdev->dev, "timeout waiting for SD bus idle\n");
555 		return -EBUSY;
556 	}
557 
558 	return 0;
559 }
560 
561 static int renesas_sdhi_write16_hook(struct tmio_mmc_host *host, int addr)
562 {
563 	u32 bit = TMIO_STAT_SCLKDIVEN;
564 
565 	switch (addr) {
566 	case CTL_SD_CMD:
567 	case CTL_STOP_INTERNAL_ACTION:
568 	case CTL_XFER_BLK_COUNT:
569 	case CTL_SD_XFER_LEN:
570 	case CTL_SD_MEM_CARD_OPT:
571 	case CTL_TRANSACTION_CTL:
572 	case CTL_DMA_ENABLE:
573 	case HOST_MODE:
574 		if (host->pdata->flags & TMIO_MMC_HAVE_CBSY)
575 			bit = TMIO_STAT_CMD_BUSY;
576 		/* fallthrough */
577 	case CTL_SD_CARD_CLK_CTL:
578 		return renesas_sdhi_wait_idle(host, bit);
579 	}
580 
581 	return 0;
582 }
583 
584 static int renesas_sdhi_multi_io_quirk(struct mmc_card *card,
585 				       unsigned int direction, int blk_size)
586 {
587 	/*
588 	 * In Renesas controllers, when performing a
589 	 * multiple block read of one or two blocks,
590 	 * depending on the timing with which the
591 	 * response register is read, the response
592 	 * value may not be read properly.
593 	 * Use single block read for this HW bug
594 	 */
595 	if ((direction == MMC_DATA_READ) &&
596 	    blk_size == 2)
597 		return 1;
598 
599 	return blk_size;
600 }
601 
602 static void renesas_sdhi_enable_dma(struct tmio_mmc_host *host, bool enable)
603 {
604 	/* Iff regs are 8 byte apart, sdbuf is 64 bit. Otherwise always 32. */
605 	int width = (host->bus_shift == 2) ? 64 : 32;
606 
607 	sd_ctrl_write16(host, CTL_DMA_ENABLE, enable ? DMA_ENABLE_DMASDRW : 0);
608 	renesas_sdhi_sdbuf_width(host, enable ? width : 16);
609 }
610 
611 static const struct renesas_sdhi_quirks sdhi_quirks_4tap_nohs400 = {
612 	.hs400_disabled = true,
613 	.hs400_4taps = true,
614 };
615 
616 static const struct renesas_sdhi_quirks sdhi_quirks_4tap = {
617 	.hs400_4taps = true,
618 };
619 
620 static const struct renesas_sdhi_quirks sdhi_quirks_nohs400 = {
621 	.hs400_disabled = true,
622 };
623 
624 static const struct soc_device_attribute sdhi_quirks_match[]  = {
625 	{ .soc_id = "r8a774a1", .revision = "ES1.[012]", .data = &sdhi_quirks_4tap_nohs400 },
626 	{ .soc_id = "r8a7795", .revision = "ES1.*", .data = &sdhi_quirks_4tap_nohs400 },
627 	{ .soc_id = "r8a7795", .revision = "ES2.0", .data = &sdhi_quirks_4tap },
628 	{ .soc_id = "r8a7796", .revision = "ES1.[012]", .data = &sdhi_quirks_4tap_nohs400 },
629 	{ .soc_id = "r8a77980", .data = &sdhi_quirks_nohs400 },
630 	{ /* Sentinel. */ },
631 };
632 
633 int renesas_sdhi_probe(struct platform_device *pdev,
634 		       const struct tmio_mmc_dma_ops *dma_ops)
635 {
636 	struct tmio_mmc_data *mmd = pdev->dev.platform_data;
637 	const struct renesas_sdhi_quirks *quirks = NULL;
638 	const struct renesas_sdhi_of_data *of_data;
639 	const struct soc_device_attribute *attr;
640 	struct tmio_mmc_data *mmc_data;
641 	struct tmio_mmc_dma *dma_priv;
642 	struct tmio_mmc_host *host;
643 	struct renesas_sdhi *priv;
644 	int num_irqs, irq, ret, i;
645 	struct resource *res;
646 	u16 ver;
647 
648 	of_data = of_device_get_match_data(&pdev->dev);
649 
650 	attr = soc_device_match(sdhi_quirks_match);
651 	if (attr)
652 		quirks = attr->data;
653 
654 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
655 	if (!res)
656 		return -EINVAL;
657 
658 	priv = devm_kzalloc(&pdev->dev, sizeof(struct renesas_sdhi),
659 			    GFP_KERNEL);
660 	if (!priv)
661 		return -ENOMEM;
662 
663 	priv->quirks = quirks;
664 	mmc_data = &priv->mmc_data;
665 	dma_priv = &priv->dma_priv;
666 
667 	priv->clk = devm_clk_get(&pdev->dev, NULL);
668 	if (IS_ERR(priv->clk)) {
669 		ret = PTR_ERR(priv->clk);
670 		dev_err(&pdev->dev, "cannot get clock: %d\n", ret);
671 		return ret;
672 	}
673 
674 	/*
675 	 * Some controllers provide a 2nd clock just to run the internal card
676 	 * detection logic. Unfortunately, the existing driver architecture does
677 	 * not support a separation of clocks for runtime PM usage. When
678 	 * native hotplug is used, the tmio driver assumes that the core
679 	 * must continue to run for card detect to stay active, so we cannot
680 	 * disable it.
681 	 * Additionally, it is prohibited to supply a clock to the core but not
682 	 * to the card detect circuit. That leaves us with if separate clocks
683 	 * are presented, we must treat them both as virtually 1 clock.
684 	 */
685 	priv->clk_cd = devm_clk_get(&pdev->dev, "cd");
686 	if (IS_ERR(priv->clk_cd))
687 		priv->clk_cd = NULL;
688 
689 	priv->pinctrl = devm_pinctrl_get(&pdev->dev);
690 	if (!IS_ERR(priv->pinctrl)) {
691 		priv->pins_default = pinctrl_lookup_state(priv->pinctrl,
692 						PINCTRL_STATE_DEFAULT);
693 		priv->pins_uhs = pinctrl_lookup_state(priv->pinctrl,
694 						"state_uhs");
695 	}
696 
697 	host = tmio_mmc_host_alloc(pdev, mmc_data);
698 	if (IS_ERR(host))
699 		return PTR_ERR(host);
700 
701 	if (of_data) {
702 		mmc_data->flags |= of_data->tmio_flags;
703 		mmc_data->ocr_mask = of_data->tmio_ocr_mask;
704 		mmc_data->capabilities |= of_data->capabilities;
705 		mmc_data->capabilities2 |= of_data->capabilities2;
706 		mmc_data->dma_rx_offset = of_data->dma_rx_offset;
707 		mmc_data->max_blk_count = of_data->max_blk_count;
708 		mmc_data->max_segs = of_data->max_segs;
709 		dma_priv->dma_buswidth = of_data->dma_buswidth;
710 		host->bus_shift = of_data->bus_shift;
711 	}
712 
713 	host->write16_hook	= renesas_sdhi_write16_hook;
714 	host->clk_enable	= renesas_sdhi_clk_enable;
715 	host->clk_disable	= renesas_sdhi_clk_disable;
716 	host->set_clock		= renesas_sdhi_set_clock;
717 	host->multi_io_quirk	= renesas_sdhi_multi_io_quirk;
718 	host->dma_ops		= dma_ops;
719 
720 	if (quirks && quirks->hs400_disabled)
721 		host->mmc->caps2 &= ~(MMC_CAP2_HS400 | MMC_CAP2_HS400_ES);
722 
723 	/* For some SoC, we disable internal WP. GPIO may override this */
724 	if (mmc_can_gpio_ro(host->mmc))
725 		mmc_data->capabilities2 &= ~MMC_CAP2_NO_WRITE_PROTECT;
726 
727 	/* SDR speeds are only available on Gen2+ */
728 	if (mmc_data->flags & TMIO_MMC_MIN_RCAR2) {
729 		/* card_busy caused issues on r8a73a4 (pre-Gen2) CD-less SDHI */
730 		host->ops.card_busy = renesas_sdhi_card_busy;
731 		host->ops.start_signal_voltage_switch =
732 			renesas_sdhi_start_signal_voltage_switch;
733 		host->sdcard_irq_setbit_mask = TMIO_STAT_ALWAYS_SET_27;
734 
735 		/* SDR and HS200/400 registers requires HW reset */
736 		if (of_data && of_data->scc_offset) {
737 			priv->scc_ctl = host->ctl + of_data->scc_offset;
738 			host->mmc->caps |= MMC_CAP_HW_RESET;
739 			host->hw_reset = renesas_sdhi_hw_reset;
740 		}
741 	}
742 
743 	/* Orginally registers were 16 bit apart, could be 32 or 64 nowadays */
744 	if (!host->bus_shift && resource_size(res) > 0x100) /* old way to determine the shift */
745 		host->bus_shift = 1;
746 
747 	if (mmd)
748 		*mmc_data = *mmd;
749 
750 	dma_priv->filter = shdma_chan_filter;
751 	dma_priv->enable = renesas_sdhi_enable_dma;
752 
753 	mmc_data->alignment_shift = 1; /* 2-byte alignment */
754 	mmc_data->capabilities |= MMC_CAP_MMC_HIGHSPEED;
755 
756 	/*
757 	 * All SDHI blocks support 2-byte and larger block sizes in 4-bit
758 	 * bus width mode.
759 	 */
760 	mmc_data->flags |= TMIO_MMC_BLKSZ_2BYTES;
761 
762 	/*
763 	 * All SDHI blocks support SDIO IRQ signalling.
764 	 */
765 	mmc_data->flags |= TMIO_MMC_SDIO_IRQ;
766 
767 	/* All SDHI have CMD12 control bit */
768 	mmc_data->flags |= TMIO_MMC_HAVE_CMD12_CTRL;
769 
770 	/* All SDHI have SDIO status bits which must be 1 */
771 	mmc_data->flags |= TMIO_MMC_SDIO_STATUS_SETBITS;
772 
773 	ret = renesas_sdhi_clk_enable(host);
774 	if (ret)
775 		goto efree;
776 
777 	ver = sd_ctrl_read16(host, CTL_VERSION);
778 	/* GEN2_SDR104 is first known SDHI to use 32bit block count */
779 	if (ver < SDHI_VER_GEN2_SDR104 && mmc_data->max_blk_count > U16_MAX)
780 		mmc_data->max_blk_count = U16_MAX;
781 
782 	/* One Gen2 SDHI incarnation does NOT have a CBSY bit */
783 	if (ver == SDHI_VER_GEN2_SDR50)
784 		mmc_data->flags &= ~TMIO_MMC_HAVE_CBSY;
785 
786 	ret = tmio_mmc_host_probe(host);
787 	if (ret < 0)
788 		goto edisclk;
789 
790 	/* Enable tuning iff we have an SCC and a supported mode */
791 	if (of_data && of_data->scc_offset &&
792 	    (host->mmc->caps & MMC_CAP_UHS_SDR104 ||
793 	     host->mmc->caps2 & (MMC_CAP2_HS200_1_8V_SDR |
794 				 MMC_CAP2_HS400_1_8V))) {
795 		const struct renesas_sdhi_scc *taps = of_data->taps;
796 		bool use_4tap = priv->quirks && priv->quirks->hs400_4taps;
797 		bool hit = false;
798 
799 		for (i = 0; i < of_data->taps_num; i++) {
800 			if (taps[i].clk_rate == 0 ||
801 			    taps[i].clk_rate == host->mmc->f_max) {
802 				priv->scc_tappos = taps->tap;
803 				priv->scc_tappos_hs400 = use_4tap ?
804 							 taps->tap_hs400_4tap :
805 							 taps->tap;
806 				hit = true;
807 				break;
808 			}
809 		}
810 
811 		if (!hit)
812 			dev_warn(&host->pdev->dev, "Unknown clock rate for tuning\n");
813 
814 		host->init_tuning = renesas_sdhi_init_tuning;
815 		host->prepare_tuning = renesas_sdhi_prepare_tuning;
816 		host->select_tuning = renesas_sdhi_select_tuning;
817 		host->check_scc_error = renesas_sdhi_check_scc_error;
818 		host->prepare_hs400_tuning =
819 			renesas_sdhi_prepare_hs400_tuning;
820 		host->hs400_downgrade = renesas_sdhi_disable_scc;
821 		host->hs400_complete = renesas_sdhi_hs400_complete;
822 	}
823 
824 	num_irqs = platform_irq_count(pdev);
825 	if (num_irqs < 0) {
826 		ret = num_irqs;
827 		goto eirq;
828 	}
829 
830 	/* There must be at least one IRQ source */
831 	if (!num_irqs) {
832 		ret = -ENXIO;
833 		goto eirq;
834 	}
835 
836 	for (i = 0; i < num_irqs; i++) {
837 		irq = platform_get_irq(pdev, i);
838 		if (irq < 0) {
839 			ret = irq;
840 			goto eirq;
841 		}
842 
843 		ret = devm_request_irq(&pdev->dev, irq, tmio_mmc_irq, 0,
844 				       dev_name(&pdev->dev), host);
845 		if (ret)
846 			goto eirq;
847 	}
848 
849 	dev_info(&pdev->dev, "%s base at 0x%08lx max clock rate %u MHz\n",
850 		 mmc_hostname(host->mmc), (unsigned long)
851 		 (platform_get_resource(pdev, IORESOURCE_MEM, 0)->start),
852 		 host->mmc->f_max / 1000000);
853 
854 	return ret;
855 
856 eirq:
857 	tmio_mmc_host_remove(host);
858 edisclk:
859 	renesas_sdhi_clk_disable(host);
860 efree:
861 	tmio_mmc_host_free(host);
862 
863 	return ret;
864 }
865 EXPORT_SYMBOL_GPL(renesas_sdhi_probe);
866 
867 int renesas_sdhi_remove(struct platform_device *pdev)
868 {
869 	struct tmio_mmc_host *host = platform_get_drvdata(pdev);
870 
871 	tmio_mmc_host_remove(host);
872 	renesas_sdhi_clk_disable(host);
873 
874 	return 0;
875 }
876 EXPORT_SYMBOL_GPL(renesas_sdhi_remove);
877 
878 MODULE_LICENSE("GPL v2");
879