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_SMPCMP       0x00C
254 #define SH_MOBILE_SDHI_SCC_TMPPORT2	0x00E
255 
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 #define SH_MOBILE_SDHI_SCC_CKSEL_DTSEL		BIT(0)
261 
262 #define SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN	BIT(0)
263 
264 #define SH_MOBILE_SDHI_SCC_RVSREQ_REQTAPDOWN	BIT(0)
265 #define SH_MOBILE_SDHI_SCC_RVSREQ_REQTAPUP	BIT(1)
266 #define SH_MOBILE_SDHI_SCC_RVSREQ_RVSERR	BIT(2)
267 
268 #define SH_MOBILE_SDHI_SCC_SMPCMP_CMD_REQDOWN	BIT(8)
269 #define SH_MOBILE_SDHI_SCC_SMPCMP_CMD_REQUP	BIT(24)
270 #define SH_MOBILE_SDHI_SCC_SMPCMP_CMD_ERR	(BIT(8) | BIT(24))
271 
272 #define SH_MOBILE_SDHI_SCC_TMPPORT2_HS400OSEL	BIT(4)
273 #define SH_MOBILE_SDHI_SCC_TMPPORT2_HS400EN	BIT(31)
274 
275 static inline u32 sd_scc_read32(struct tmio_mmc_host *host,
276 				struct renesas_sdhi *priv, int addr)
277 {
278 	return readl(priv->scc_ctl + (addr << host->bus_shift));
279 }
280 
281 static inline void sd_scc_write32(struct tmio_mmc_host *host,
282 				  struct renesas_sdhi *priv,
283 				  int addr, u32 val)
284 {
285 	writel(val, priv->scc_ctl + (addr << host->bus_shift));
286 }
287 
288 static unsigned int renesas_sdhi_init_tuning(struct tmio_mmc_host *host)
289 {
290 	struct renesas_sdhi *priv;
291 
292 	priv = host_to_priv(host);
293 
294 	/* Initialize SCC */
295 	sd_ctrl_write32_as_16_and_16(host, CTL_STATUS, 0x0);
296 
297 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
298 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
299 
300 	/* set sampling clock selection range */
301 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL,
302 		       SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN |
303 		       0x8 << SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT);
304 
305 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL,
306 		       SH_MOBILE_SDHI_SCC_CKSEL_DTSEL |
307 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL));
308 
309 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
310 		       ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &
311 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
312 
313 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DT2FF, priv->scc_tappos);
314 
315 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
316 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
317 
318 	/* Read TAPNUM */
319 	return (sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL) >>
320 		SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT) &
321 		SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_MASK;
322 }
323 
324 static void renesas_sdhi_hs400_complete(struct mmc_host *mmc)
325 {
326 	struct tmio_mmc_host *host = mmc_priv(mmc);
327 	struct renesas_sdhi *priv = host_to_priv(host);
328 
329 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
330 		sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
331 
332 	/* Set HS400 mode */
333 	sd_ctrl_write16(host, CTL_SDIF_MODE, 0x0001 |
334 			sd_ctrl_read16(host, CTL_SDIF_MODE));
335 
336 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DT2FF,
337 		       priv->scc_tappos_hs400);
338 
339 	/* Gen3 can't do automatic tap correction with HS400, so disable it */
340 	if (sd_ctrl_read16(host, CTL_VERSION) == SDHI_VER_GEN3_SDMMC)
341 		sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
342 			       ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &
343 			       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
344 
345 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TMPPORT2,
346 		       (SH_MOBILE_SDHI_SCC_TMPPORT2_HS400EN |
347 			SH_MOBILE_SDHI_SCC_TMPPORT2_HS400OSEL) |
348 			sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_TMPPORT2));
349 
350 	/* Set the sampling clock selection range of HS400 mode */
351 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL,
352 		       SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN |
353 		       0x4 << SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT);
354 
355 
356 	if (priv->quirks && priv->quirks->hs400_4taps)
357 		sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET,
358 			       priv->tap_set / 2);
359 
360 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL,
361 		       SH_MOBILE_SDHI_SCC_CKSEL_DTSEL |
362 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL));
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_reset_scc(struct tmio_mmc_host *host,
369 				   struct renesas_sdhi *priv)
370 {
371 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
372 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
373 
374 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL,
375 		       ~SH_MOBILE_SDHI_SCC_CKSEL_DTSEL &
376 		       sd_scc_read32(host, priv,
377 				     SH_MOBILE_SDHI_SCC_CKSEL));
378 }
379 
380 static void renesas_sdhi_disable_scc(struct mmc_host *mmc)
381 {
382 	struct tmio_mmc_host *host = mmc_priv(mmc);
383 	struct renesas_sdhi *priv = host_to_priv(host);
384 
385 	renesas_sdhi_reset_scc(host, priv);
386 
387 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL,
388 		       ~SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN &
389 		       sd_scc_read32(host, priv,
390 				     SH_MOBILE_SDHI_SCC_DTCNTL));
391 
392 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
393 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
394 }
395 
396 static void renesas_sdhi_reset_hs400_mode(struct tmio_mmc_host *host,
397 					  struct renesas_sdhi *priv)
398 {
399 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
400 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
401 
402 	/* Reset HS400 mode */
403 	sd_ctrl_write16(host, CTL_SDIF_MODE, ~0x0001 &
404 			sd_ctrl_read16(host, CTL_SDIF_MODE));
405 
406 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DT2FF, priv->scc_tappos);
407 
408 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TMPPORT2,
409 		       ~(SH_MOBILE_SDHI_SCC_TMPPORT2_HS400EN |
410 			 SH_MOBILE_SDHI_SCC_TMPPORT2_HS400OSEL) &
411 			sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_TMPPORT2));
412 
413 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
414 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
415 }
416 
417 static int renesas_sdhi_prepare_hs400_tuning(struct mmc_host *mmc, struct mmc_ios *ios)
418 {
419 	struct tmio_mmc_host *host = mmc_priv(mmc);
420 
421 	renesas_sdhi_reset_hs400_mode(host, host_to_priv(host));
422 	return 0;
423 }
424 
425 #define SH_MOBILE_SDHI_MAX_TAP 3
426 
427 static int renesas_sdhi_select_tuning(struct tmio_mmc_host *host)
428 {
429 	struct renesas_sdhi *priv = host_to_priv(host);
430 	unsigned long tap_cnt;  /* counter of tuning success */
431 	unsigned long tap_start;/* start position of tuning success */
432 	unsigned long tap_end;  /* end position of tuning success */
433 	unsigned long ntap;     /* temporary counter of tuning success */
434 	unsigned long i;
435 
436 	priv->doing_tune = false;
437 
438 	/* Clear SCC_RVSREQ */
439 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0);
440 
441 	/*
442 	 * When tuning CMD19 is issued twice for each tap, merge the
443 	 * result requiring the tap to be good in both runs before
444 	 * considering it for tuning selection.
445 	 */
446 	for (i = 0; i < priv->tap_num * 2; i++) {
447 		int offset = priv->tap_num * (i < priv->tap_num ? 1 : -1);
448 
449 		if (!test_bit(i, priv->taps))
450 			clear_bit(i + offset, priv->taps);
451 	}
452 
453 	/*
454 	 * Find the longest consecutive run of successful probes.  If that
455 	 * is more than SH_MOBILE_SDHI_MAX_TAP probes long then use the
456 	 * center index as the tap.
457 	 */
458 	tap_cnt = 0;
459 	ntap = 0;
460 	tap_start = 0;
461 	tap_end = 0;
462 	for (i = 0; i < priv->tap_num * 2; i++) {
463 		if (test_bit(i, priv->taps)) {
464 			ntap++;
465 		} else {
466 			if (ntap > tap_cnt) {
467 				tap_start = i - ntap;
468 				tap_end = i - 1;
469 				tap_cnt = ntap;
470 			}
471 			ntap = 0;
472 		}
473 	}
474 
475 	if (ntap > tap_cnt) {
476 		tap_start = i - ntap;
477 		tap_end = i - 1;
478 		tap_cnt = ntap;
479 	}
480 
481 	if (tap_cnt >= SH_MOBILE_SDHI_MAX_TAP)
482 		priv->tap_set = (tap_start + tap_end) / 2 % priv->tap_num;
483 	else
484 		return -EIO;
485 
486 	/* Set SCC */
487 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET, priv->tap_set);
488 
489 	/* Enable auto re-tuning */
490 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
491 		       SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN |
492 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
493 
494 	return 0;
495 }
496 
497 static int renesas_sdhi_execute_tuning(struct tmio_mmc_host *host, u32 opcode)
498 {
499 	struct renesas_sdhi *priv = host_to_priv(host);
500 	int i;
501 
502 	priv->tap_num = renesas_sdhi_init_tuning(host);
503 	if (!priv->tap_num)
504 		return 0; /* Tuning is not supported */
505 
506 	if (priv->tap_num * 2 >= sizeof(priv->taps) * BITS_PER_BYTE) {
507 		dev_err(&host->pdev->dev,
508 			"Too many taps, please update 'taps' in tmio_mmc_host!\n");
509 		return -EINVAL;
510 	}
511 
512 	priv->doing_tune = true;
513 	bitmap_zero(priv->taps, priv->tap_num * 2);
514 
515 	/* Issue CMD19 twice for each tap */
516 	for (i = 0; i < 2 * priv->tap_num; i++) {
517 		/* Set sampling clock position */
518 		sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET, i % priv->tap_num);
519 
520 		if (mmc_send_tuning(host->mmc, opcode, NULL) == 0)
521 			set_bit(i, priv->taps);
522 	}
523 
524 	return renesas_sdhi_select_tuning(host);
525 }
526 
527 static bool renesas_sdhi_manual_correction(struct tmio_mmc_host *host, bool use_4tap)
528 {
529 	struct renesas_sdhi *priv = host_to_priv(host);
530 	unsigned long new_tap = priv->tap_set;
531 	u32 val;
532 
533 	val = sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ);
534 	if (!val)
535 		return false;
536 
537 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0);
538 
539 	/* Change TAP position according to correction status */
540 	if (sd_ctrl_read16(host, CTL_VERSION) == SDHI_VER_GEN3_SDMMC &&
541 	    host->mmc->ios.timing == MMC_TIMING_MMC_HS400) {
542 		/*
543 		 * With HS400, the DAT signal is based on DS, not CLK.
544 		 * Therefore, use only CMD status.
545 		 */
546 		u32 smpcmp = sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_SMPCMP) &
547 					   SH_MOBILE_SDHI_SCC_SMPCMP_CMD_ERR;
548 		if (!smpcmp)
549 			return false;	/* no error in CMD signal */
550 		else if (smpcmp == SH_MOBILE_SDHI_SCC_SMPCMP_CMD_REQUP)
551 			new_tap++;
552 		else if (smpcmp == SH_MOBILE_SDHI_SCC_SMPCMP_CMD_REQDOWN)
553 			new_tap--;
554 		else
555 			return true;	/* need retune */
556 	} else {
557 		if (val & SH_MOBILE_SDHI_SCC_RVSREQ_RVSERR)
558 			return true;    /* need retune */
559 		else if (val & SH_MOBILE_SDHI_SCC_RVSREQ_REQTAPUP)
560 			new_tap++;
561 		else if (val & SH_MOBILE_SDHI_SCC_RVSREQ_REQTAPDOWN)
562 			new_tap--;
563 		else
564 			return false;
565 	}
566 
567 	priv->tap_set = (new_tap % priv->tap_num);
568 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET,
569 		       priv->tap_set / (use_4tap ? 2 : 1));
570 
571 	return false;
572 }
573 
574 static bool renesas_sdhi_auto_correction(struct tmio_mmc_host *host)
575 {
576 	struct renesas_sdhi *priv = host_to_priv(host);
577 
578 	/* Check SCC error */
579 	if (sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ) &
580 	    SH_MOBILE_SDHI_SCC_RVSREQ_RVSERR) {
581 		sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0);
582 		return true;
583 	}
584 
585 	return false;
586 }
587 
588 static bool renesas_sdhi_check_scc_error(struct tmio_mmc_host *host)
589 {
590 	struct renesas_sdhi *priv = host_to_priv(host);
591 	bool use_4tap = priv->quirks && priv->quirks->hs400_4taps;
592 
593 	/*
594 	 * Skip checking SCC errors when running on 4 taps in HS400 mode as
595 	 * any retuning would still result in the same 4 taps being used.
596 	 */
597 	if (!(host->mmc->ios.timing == MMC_TIMING_UHS_SDR104) &&
598 	    !(host->mmc->ios.timing == MMC_TIMING_MMC_HS200) &&
599 	    !(host->mmc->ios.timing == MMC_TIMING_MMC_HS400 && !use_4tap))
600 		return false;
601 
602 	if (mmc_doing_retune(host->mmc) || priv->doing_tune)
603 		return false;
604 
605 	if (sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL) &
606 	    SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN)
607 		return renesas_sdhi_auto_correction(host);
608 
609 	return renesas_sdhi_manual_correction(host, use_4tap);
610 }
611 
612 static void renesas_sdhi_hw_reset(struct tmio_mmc_host *host)
613 {
614 	struct renesas_sdhi *priv;
615 
616 	priv = host_to_priv(host);
617 
618 	renesas_sdhi_reset_scc(host, priv);
619 	renesas_sdhi_reset_hs400_mode(host, priv);
620 
621 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
622 			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
623 
624 	sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
625 		       ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &
626 		       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
627 
628 	if (host->pdata->flags & TMIO_MMC_MIN_RCAR2)
629 		sd_ctrl_write32_as_16_and_16(host, CTL_IRQ_MASK,
630 					     TMIO_MASK_INIT_RCAR2);
631 }
632 
633 static int renesas_sdhi_wait_idle(struct tmio_mmc_host *host, u32 bit)
634 {
635 	int timeout = 1000;
636 	/* CBSY is set when busy, SCLKDIVEN is cleared when busy */
637 	u32 wait_state = (bit == TMIO_STAT_CMD_BUSY ? TMIO_STAT_CMD_BUSY : 0);
638 
639 	while (--timeout && (sd_ctrl_read16_and_16_as_32(host, CTL_STATUS)
640 			      & bit) == wait_state)
641 		udelay(1);
642 
643 	if (!timeout) {
644 		dev_warn(&host->pdev->dev, "timeout waiting for SD bus idle\n");
645 		return -EBUSY;
646 	}
647 
648 	return 0;
649 }
650 
651 static int renesas_sdhi_write16_hook(struct tmio_mmc_host *host, int addr)
652 {
653 	u32 bit = TMIO_STAT_SCLKDIVEN;
654 
655 	switch (addr) {
656 	case CTL_SD_CMD:
657 	case CTL_STOP_INTERNAL_ACTION:
658 	case CTL_XFER_BLK_COUNT:
659 	case CTL_SD_XFER_LEN:
660 	case CTL_SD_MEM_CARD_OPT:
661 	case CTL_TRANSACTION_CTL:
662 	case CTL_DMA_ENABLE:
663 	case HOST_MODE:
664 		if (host->pdata->flags & TMIO_MMC_HAVE_CBSY)
665 			bit = TMIO_STAT_CMD_BUSY;
666 		/* fallthrough */
667 	case CTL_SD_CARD_CLK_CTL:
668 		return renesas_sdhi_wait_idle(host, bit);
669 	}
670 
671 	return 0;
672 }
673 
674 static int renesas_sdhi_multi_io_quirk(struct mmc_card *card,
675 				       unsigned int direction, int blk_size)
676 {
677 	/*
678 	 * In Renesas controllers, when performing a
679 	 * multiple block read of one or two blocks,
680 	 * depending on the timing with which the
681 	 * response register is read, the response
682 	 * value may not be read properly.
683 	 * Use single block read for this HW bug
684 	 */
685 	if ((direction == MMC_DATA_READ) &&
686 	    blk_size == 2)
687 		return 1;
688 
689 	return blk_size;
690 }
691 
692 static void renesas_sdhi_enable_dma(struct tmio_mmc_host *host, bool enable)
693 {
694 	/* Iff regs are 8 byte apart, sdbuf is 64 bit. Otherwise always 32. */
695 	int width = (host->bus_shift == 2) ? 64 : 32;
696 
697 	sd_ctrl_write16(host, CTL_DMA_ENABLE, enable ? DMA_ENABLE_DMASDRW : 0);
698 	renesas_sdhi_sdbuf_width(host, enable ? width : 16);
699 }
700 
701 static const struct renesas_sdhi_quirks sdhi_quirks_4tap_nohs400 = {
702 	.hs400_disabled = true,
703 	.hs400_4taps = true,
704 };
705 
706 static const struct renesas_sdhi_quirks sdhi_quirks_4tap = {
707 	.hs400_4taps = true,
708 };
709 
710 static const struct renesas_sdhi_quirks sdhi_quirks_nohs400 = {
711 	.hs400_disabled = true,
712 };
713 
714 static const struct soc_device_attribute sdhi_quirks_match[]  = {
715 	{ .soc_id = "r8a774a1", .revision = "ES1.[012]", .data = &sdhi_quirks_4tap_nohs400 },
716 	{ .soc_id = "r8a7795", .revision = "ES1.*", .data = &sdhi_quirks_4tap_nohs400 },
717 	{ .soc_id = "r8a7795", .revision = "ES2.0", .data = &sdhi_quirks_4tap },
718 	{ .soc_id = "r8a7796", .revision = "ES1.[012]", .data = &sdhi_quirks_4tap_nohs400 },
719 	{ .soc_id = "r8a77980", .data = &sdhi_quirks_nohs400 },
720 	{ /* Sentinel. */ },
721 };
722 
723 int renesas_sdhi_probe(struct platform_device *pdev,
724 		       const struct tmio_mmc_dma_ops *dma_ops)
725 {
726 	struct tmio_mmc_data *mmd = pdev->dev.platform_data;
727 	const struct renesas_sdhi_quirks *quirks = NULL;
728 	const struct renesas_sdhi_of_data *of_data;
729 	const struct soc_device_attribute *attr;
730 	struct tmio_mmc_data *mmc_data;
731 	struct tmio_mmc_dma *dma_priv;
732 	struct tmio_mmc_host *host;
733 	struct renesas_sdhi *priv;
734 	int num_irqs, irq, ret, i;
735 	struct resource *res;
736 	u16 ver;
737 
738 	of_data = of_device_get_match_data(&pdev->dev);
739 
740 	attr = soc_device_match(sdhi_quirks_match);
741 	if (attr)
742 		quirks = attr->data;
743 
744 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
745 	if (!res)
746 		return -EINVAL;
747 
748 	priv = devm_kzalloc(&pdev->dev, sizeof(struct renesas_sdhi),
749 			    GFP_KERNEL);
750 	if (!priv)
751 		return -ENOMEM;
752 
753 	priv->quirks = quirks;
754 	mmc_data = &priv->mmc_data;
755 	dma_priv = &priv->dma_priv;
756 
757 	priv->clk = devm_clk_get(&pdev->dev, NULL);
758 	if (IS_ERR(priv->clk)) {
759 		ret = PTR_ERR(priv->clk);
760 		dev_err(&pdev->dev, "cannot get clock: %d\n", ret);
761 		return ret;
762 	}
763 
764 	/*
765 	 * Some controllers provide a 2nd clock just to run the internal card
766 	 * detection logic. Unfortunately, the existing driver architecture does
767 	 * not support a separation of clocks for runtime PM usage. When
768 	 * native hotplug is used, the tmio driver assumes that the core
769 	 * must continue to run for card detect to stay active, so we cannot
770 	 * disable it.
771 	 * Additionally, it is prohibited to supply a clock to the core but not
772 	 * to the card detect circuit. That leaves us with if separate clocks
773 	 * are presented, we must treat them both as virtually 1 clock.
774 	 */
775 	priv->clk_cd = devm_clk_get(&pdev->dev, "cd");
776 	if (IS_ERR(priv->clk_cd))
777 		priv->clk_cd = NULL;
778 
779 	priv->pinctrl = devm_pinctrl_get(&pdev->dev);
780 	if (!IS_ERR(priv->pinctrl)) {
781 		priv->pins_default = pinctrl_lookup_state(priv->pinctrl,
782 						PINCTRL_STATE_DEFAULT);
783 		priv->pins_uhs = pinctrl_lookup_state(priv->pinctrl,
784 						"state_uhs");
785 	}
786 
787 	host = tmio_mmc_host_alloc(pdev, mmc_data);
788 	if (IS_ERR(host))
789 		return PTR_ERR(host);
790 
791 	if (of_data) {
792 		mmc_data->flags |= of_data->tmio_flags;
793 		mmc_data->ocr_mask = of_data->tmio_ocr_mask;
794 		mmc_data->capabilities |= of_data->capabilities;
795 		mmc_data->capabilities2 |= of_data->capabilities2;
796 		mmc_data->dma_rx_offset = of_data->dma_rx_offset;
797 		mmc_data->max_blk_count = of_data->max_blk_count;
798 		mmc_data->max_segs = of_data->max_segs;
799 		dma_priv->dma_buswidth = of_data->dma_buswidth;
800 		host->bus_shift = of_data->bus_shift;
801 	}
802 
803 	host->write16_hook	= renesas_sdhi_write16_hook;
804 	host->clk_enable	= renesas_sdhi_clk_enable;
805 	host->clk_disable	= renesas_sdhi_clk_disable;
806 	host->set_clock		= renesas_sdhi_set_clock;
807 	host->multi_io_quirk	= renesas_sdhi_multi_io_quirk;
808 	host->dma_ops		= dma_ops;
809 
810 	if (quirks && quirks->hs400_disabled)
811 		host->mmc->caps2 &= ~(MMC_CAP2_HS400 | MMC_CAP2_HS400_ES);
812 
813 	/* For some SoC, we disable internal WP. GPIO may override this */
814 	if (mmc_can_gpio_ro(host->mmc))
815 		mmc_data->capabilities2 &= ~MMC_CAP2_NO_WRITE_PROTECT;
816 
817 	/* SDR speeds are only available on Gen2+ */
818 	if (mmc_data->flags & TMIO_MMC_MIN_RCAR2) {
819 		/* card_busy caused issues on r8a73a4 (pre-Gen2) CD-less SDHI */
820 		host->ops.card_busy = renesas_sdhi_card_busy;
821 		host->ops.start_signal_voltage_switch =
822 			renesas_sdhi_start_signal_voltage_switch;
823 		host->sdcard_irq_setbit_mask = TMIO_STAT_ALWAYS_SET_27;
824 
825 		/* SDR and HS200/400 registers requires HW reset */
826 		if (of_data && of_data->scc_offset) {
827 			priv->scc_ctl = host->ctl + of_data->scc_offset;
828 			host->mmc->caps |= MMC_CAP_HW_RESET;
829 			host->hw_reset = renesas_sdhi_hw_reset;
830 		}
831 	}
832 
833 	/* Orginally registers were 16 bit apart, could be 32 or 64 nowadays */
834 	if (!host->bus_shift && resource_size(res) > 0x100) /* old way to determine the shift */
835 		host->bus_shift = 1;
836 
837 	if (mmd)
838 		*mmc_data = *mmd;
839 
840 	dma_priv->filter = shdma_chan_filter;
841 	dma_priv->enable = renesas_sdhi_enable_dma;
842 
843 	mmc_data->alignment_shift = 1; /* 2-byte alignment */
844 	mmc_data->capabilities |= MMC_CAP_MMC_HIGHSPEED;
845 
846 	/*
847 	 * All SDHI blocks support 2-byte and larger block sizes in 4-bit
848 	 * bus width mode.
849 	 */
850 	mmc_data->flags |= TMIO_MMC_BLKSZ_2BYTES;
851 
852 	/*
853 	 * All SDHI blocks support SDIO IRQ signalling.
854 	 */
855 	mmc_data->flags |= TMIO_MMC_SDIO_IRQ;
856 
857 	/* All SDHI have CMD12 control bit */
858 	mmc_data->flags |= TMIO_MMC_HAVE_CMD12_CTRL;
859 
860 	/* All SDHI have SDIO status bits which must be 1 */
861 	mmc_data->flags |= TMIO_MMC_SDIO_STATUS_SETBITS;
862 
863 	ret = renesas_sdhi_clk_enable(host);
864 	if (ret)
865 		goto efree;
866 
867 	ver = sd_ctrl_read16(host, CTL_VERSION);
868 	/* GEN2_SDR104 is first known SDHI to use 32bit block count */
869 	if (ver < SDHI_VER_GEN2_SDR104 && mmc_data->max_blk_count > U16_MAX)
870 		mmc_data->max_blk_count = U16_MAX;
871 
872 	/* One Gen2 SDHI incarnation does NOT have a CBSY bit */
873 	if (ver == SDHI_VER_GEN2_SDR50)
874 		mmc_data->flags &= ~TMIO_MMC_HAVE_CBSY;
875 
876 	ret = tmio_mmc_host_probe(host);
877 	if (ret < 0)
878 		goto edisclk;
879 
880 	/* Enable tuning iff we have an SCC and a supported mode */
881 	if (of_data && of_data->scc_offset &&
882 	    (host->mmc->caps & MMC_CAP_UHS_SDR104 ||
883 	     host->mmc->caps2 & (MMC_CAP2_HS200_1_8V_SDR |
884 				 MMC_CAP2_HS400_1_8V))) {
885 		const struct renesas_sdhi_scc *taps = of_data->taps;
886 		bool use_4tap = priv->quirks && priv->quirks->hs400_4taps;
887 		bool hit = false;
888 
889 		for (i = 0; i < of_data->taps_num; i++) {
890 			if (taps[i].clk_rate == 0 ||
891 			    taps[i].clk_rate == host->mmc->f_max) {
892 				priv->scc_tappos = taps->tap;
893 				priv->scc_tappos_hs400 = use_4tap ?
894 							 taps->tap_hs400_4tap :
895 							 taps->tap;
896 				hit = true;
897 				break;
898 			}
899 		}
900 
901 		if (!hit)
902 			dev_warn(&host->pdev->dev, "Unknown clock rate for tuning\n");
903 
904 		host->execute_tuning = renesas_sdhi_execute_tuning;
905 		host->check_retune = renesas_sdhi_check_scc_error;
906 		host->ops.prepare_hs400_tuning = renesas_sdhi_prepare_hs400_tuning;
907 		host->ops.hs400_downgrade = renesas_sdhi_disable_scc;
908 		host->ops.hs400_complete = renesas_sdhi_hs400_complete;
909 	}
910 
911 	num_irqs = platform_irq_count(pdev);
912 	if (num_irqs < 0) {
913 		ret = num_irqs;
914 		goto eirq;
915 	}
916 
917 	/* There must be at least one IRQ source */
918 	if (!num_irqs) {
919 		ret = -ENXIO;
920 		goto eirq;
921 	}
922 
923 	for (i = 0; i < num_irqs; i++) {
924 		irq = platform_get_irq(pdev, i);
925 		if (irq < 0) {
926 			ret = irq;
927 			goto eirq;
928 		}
929 
930 		ret = devm_request_irq(&pdev->dev, irq, tmio_mmc_irq, 0,
931 				       dev_name(&pdev->dev), host);
932 		if (ret)
933 			goto eirq;
934 	}
935 
936 	dev_info(&pdev->dev, "%s base at 0x%08lx max clock rate %u MHz\n",
937 		 mmc_hostname(host->mmc), (unsigned long)
938 		 (platform_get_resource(pdev, IORESOURCE_MEM, 0)->start),
939 		 host->mmc->f_max / 1000000);
940 
941 	return ret;
942 
943 eirq:
944 	tmio_mmc_host_remove(host);
945 edisclk:
946 	renesas_sdhi_clk_disable(host);
947 efree:
948 	tmio_mmc_host_free(host);
949 
950 	return ret;
951 }
952 EXPORT_SYMBOL_GPL(renesas_sdhi_probe);
953 
954 int renesas_sdhi_remove(struct platform_device *pdev)
955 {
956 	struct tmio_mmc_host *host = platform_get_drvdata(pdev);
957 
958 	tmio_mmc_host_remove(host);
959 	renesas_sdhi_clk_disable(host);
960 
961 	return 0;
962 }
963 EXPORT_SYMBOL_GPL(renesas_sdhi_remove);
964 
965 MODULE_LICENSE("GPL v2");
966