mmc: renesas_sdhi: refactor calculation of best TAP
[linux-2.6-microblaze.git] / drivers / mmc / host / renesas_sdhi_core.c
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 int tap_start = 0, tap_end = 0, tap_cnt = 0, rs, re, i;
431         unsigned int taps_size = priv->tap_num * 2;
432
433         priv->doing_tune = false;
434         sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0);
435
436         /*
437          * When tuning CMD19 is issued twice for each tap, merge the
438          * result requiring the tap to be good in both runs before
439          * considering it for tuning selection.
440          */
441         for (i = 0; i < taps_size; i++) {
442                 int offset = priv->tap_num * (i < priv->tap_num ? 1 : -1);
443
444                 if (!test_bit(i, priv->taps))
445                         clear_bit(i + offset, priv->taps);
446         }
447
448         /*
449          * Find the longest consecutive run of successful probes.  If that
450          * is more than SH_MOBILE_SDHI_MAX_TAP probes long then use the
451          * center index as the tap.
452          */
453         bitmap_for_each_set_region(priv->taps, rs, re, 0, taps_size) {
454                 if (re - rs > tap_cnt) {
455                         tap_end = re;
456                         tap_start = rs;
457                         tap_cnt = tap_end - tap_start;
458                 }
459         }
460
461         if (tap_cnt >= SH_MOBILE_SDHI_MAX_TAP)
462                 priv->tap_set = (tap_start + tap_end) / 2 % priv->tap_num;
463         else
464                 return -EIO;
465
466         /* Set SCC */
467         sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET, priv->tap_set);
468
469         /* Enable auto re-tuning */
470         sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
471                        SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN |
472                        sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
473
474         return 0;
475 }
476
477 static int renesas_sdhi_execute_tuning(struct tmio_mmc_host *host, u32 opcode)
478 {
479         struct renesas_sdhi *priv = host_to_priv(host);
480         int i;
481
482         priv->tap_num = renesas_sdhi_init_tuning(host);
483         if (!priv->tap_num)
484                 return 0; /* Tuning is not supported */
485
486         if (priv->tap_num * 2 >= sizeof(priv->taps) * BITS_PER_BYTE) {
487                 dev_err(&host->pdev->dev,
488                         "Too many taps, please update 'taps' in tmio_mmc_host!\n");
489                 return -EINVAL;
490         }
491
492         priv->doing_tune = true;
493         bitmap_zero(priv->taps, priv->tap_num * 2);
494
495         /* Issue CMD19 twice for each tap */
496         for (i = 0; i < 2 * priv->tap_num; i++) {
497                 /* Set sampling clock position */
498                 sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET, i % priv->tap_num);
499
500                 if (mmc_send_tuning(host->mmc, opcode, NULL) == 0)
501                         set_bit(i, priv->taps);
502         }
503
504         return renesas_sdhi_select_tuning(host);
505 }
506
507 static bool renesas_sdhi_manual_correction(struct tmio_mmc_host *host, bool use_4tap)
508 {
509         struct renesas_sdhi *priv = host_to_priv(host);
510         unsigned long new_tap = priv->tap_set;
511         u32 val;
512
513         val = sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ);
514         if (!val)
515                 return false;
516
517         sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0);
518
519         /* Change TAP position according to correction status */
520         if (sd_ctrl_read16(host, CTL_VERSION) == SDHI_VER_GEN3_SDMMC &&
521             host->mmc->ios.timing == MMC_TIMING_MMC_HS400) {
522                 /*
523                  * With HS400, the DAT signal is based on DS, not CLK.
524                  * Therefore, use only CMD status.
525                  */
526                 u32 smpcmp = sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_SMPCMP) &
527                                            SH_MOBILE_SDHI_SCC_SMPCMP_CMD_ERR;
528                 if (!smpcmp)
529                         return false;   /* no error in CMD signal */
530                 else if (smpcmp == SH_MOBILE_SDHI_SCC_SMPCMP_CMD_REQUP)
531                         new_tap++;
532                 else if (smpcmp == SH_MOBILE_SDHI_SCC_SMPCMP_CMD_REQDOWN)
533                         new_tap--;
534                 else
535                         return true;    /* need retune */
536         } else {
537                 if (val & SH_MOBILE_SDHI_SCC_RVSREQ_RVSERR)
538                         return true;    /* need retune */
539                 else if (val & SH_MOBILE_SDHI_SCC_RVSREQ_REQTAPUP)
540                         new_tap++;
541                 else if (val & SH_MOBILE_SDHI_SCC_RVSREQ_REQTAPDOWN)
542                         new_tap--;
543                 else
544                         return false;
545         }
546
547         priv->tap_set = (new_tap % priv->tap_num);
548         sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET,
549                        priv->tap_set / (use_4tap ? 2 : 1));
550
551         return false;
552 }
553
554 static bool renesas_sdhi_auto_correction(struct tmio_mmc_host *host)
555 {
556         struct renesas_sdhi *priv = host_to_priv(host);
557
558         /* Check SCC error */
559         if (sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ) &
560             SH_MOBILE_SDHI_SCC_RVSREQ_RVSERR) {
561                 sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0);
562                 return true;
563         }
564
565         return false;
566 }
567
568 static bool renesas_sdhi_check_scc_error(struct tmio_mmc_host *host)
569 {
570         struct renesas_sdhi *priv = host_to_priv(host);
571         bool use_4tap = priv->quirks && priv->quirks->hs400_4taps;
572
573         /*
574          * Skip checking SCC errors when running on 4 taps in HS400 mode as
575          * any retuning would still result in the same 4 taps being used.
576          */
577         if (!(host->mmc->ios.timing == MMC_TIMING_UHS_SDR104) &&
578             !(host->mmc->ios.timing == MMC_TIMING_MMC_HS200) &&
579             !(host->mmc->ios.timing == MMC_TIMING_MMC_HS400 && !use_4tap))
580                 return false;
581
582         if (mmc_doing_retune(host->mmc) || priv->doing_tune)
583                 return false;
584
585         if (sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL) &
586             SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN)
587                 return renesas_sdhi_auto_correction(host);
588
589         return renesas_sdhi_manual_correction(host, use_4tap);
590 }
591
592 static void renesas_sdhi_hw_reset(struct tmio_mmc_host *host)
593 {
594         struct renesas_sdhi *priv;
595
596         priv = host_to_priv(host);
597
598         renesas_sdhi_reset_scc(host, priv);
599         renesas_sdhi_reset_hs400_mode(host, priv);
600
601         sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
602                         sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
603
604         sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
605                        ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &
606                        sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
607
608         if (host->pdata->flags & TMIO_MMC_MIN_RCAR2)
609                 sd_ctrl_write32_as_16_and_16(host, CTL_IRQ_MASK,
610                                              TMIO_MASK_INIT_RCAR2);
611 }
612
613 static int renesas_sdhi_wait_idle(struct tmio_mmc_host *host, u32 bit)
614 {
615         int timeout = 1000;
616         /* CBSY is set when busy, SCLKDIVEN is cleared when busy */
617         u32 wait_state = (bit == TMIO_STAT_CMD_BUSY ? TMIO_STAT_CMD_BUSY : 0);
618
619         while (--timeout && (sd_ctrl_read16_and_16_as_32(host, CTL_STATUS)
620                               & bit) == wait_state)
621                 udelay(1);
622
623         if (!timeout) {
624                 dev_warn(&host->pdev->dev, "timeout waiting for SD bus idle\n");
625                 return -EBUSY;
626         }
627
628         return 0;
629 }
630
631 static int renesas_sdhi_write16_hook(struct tmio_mmc_host *host, int addr)
632 {
633         u32 bit = TMIO_STAT_SCLKDIVEN;
634
635         switch (addr) {
636         case CTL_SD_CMD:
637         case CTL_STOP_INTERNAL_ACTION:
638         case CTL_XFER_BLK_COUNT:
639         case CTL_SD_XFER_LEN:
640         case CTL_SD_MEM_CARD_OPT:
641         case CTL_TRANSACTION_CTL:
642         case CTL_DMA_ENABLE:
643         case HOST_MODE:
644                 if (host->pdata->flags & TMIO_MMC_HAVE_CBSY)
645                         bit = TMIO_STAT_CMD_BUSY;
646                 /* fallthrough */
647         case CTL_SD_CARD_CLK_CTL:
648                 return renesas_sdhi_wait_idle(host, bit);
649         }
650
651         return 0;
652 }
653
654 static int renesas_sdhi_multi_io_quirk(struct mmc_card *card,
655                                        unsigned int direction, int blk_size)
656 {
657         /*
658          * In Renesas controllers, when performing a
659          * multiple block read of one or two blocks,
660          * depending on the timing with which the
661          * response register is read, the response
662          * value may not be read properly.
663          * Use single block read for this HW bug
664          */
665         if ((direction == MMC_DATA_READ) &&
666             blk_size == 2)
667                 return 1;
668
669         return blk_size;
670 }
671
672 static void renesas_sdhi_enable_dma(struct tmio_mmc_host *host, bool enable)
673 {
674         /* Iff regs are 8 byte apart, sdbuf is 64 bit. Otherwise always 32. */
675         int width = (host->bus_shift == 2) ? 64 : 32;
676
677         sd_ctrl_write16(host, CTL_DMA_ENABLE, enable ? DMA_ENABLE_DMASDRW : 0);
678         renesas_sdhi_sdbuf_width(host, enable ? width : 16);
679 }
680
681 static const struct renesas_sdhi_quirks sdhi_quirks_4tap_nohs400 = {
682         .hs400_disabled = true,
683         .hs400_4taps = true,
684 };
685
686 static const struct renesas_sdhi_quirks sdhi_quirks_4tap = {
687         .hs400_4taps = true,
688 };
689
690 static const struct renesas_sdhi_quirks sdhi_quirks_nohs400 = {
691         .hs400_disabled = true,
692 };
693
694 static const struct soc_device_attribute sdhi_quirks_match[]  = {
695         { .soc_id = "r8a774a1", .revision = "ES1.[012]", .data = &sdhi_quirks_4tap_nohs400 },
696         { .soc_id = "r8a7795", .revision = "ES1.*", .data = &sdhi_quirks_4tap_nohs400 },
697         { .soc_id = "r8a7795", .revision = "ES2.0", .data = &sdhi_quirks_4tap },
698         { .soc_id = "r8a7796", .revision = "ES1.[012]", .data = &sdhi_quirks_4tap_nohs400 },
699         { .soc_id = "r8a77980", .data = &sdhi_quirks_nohs400 },
700         { /* Sentinel. */ },
701 };
702
703 int renesas_sdhi_probe(struct platform_device *pdev,
704                        const struct tmio_mmc_dma_ops *dma_ops)
705 {
706         struct tmio_mmc_data *mmd = pdev->dev.platform_data;
707         const struct renesas_sdhi_quirks *quirks = NULL;
708         const struct renesas_sdhi_of_data *of_data;
709         const struct soc_device_attribute *attr;
710         struct tmio_mmc_data *mmc_data;
711         struct tmio_mmc_dma *dma_priv;
712         struct tmio_mmc_host *host;
713         struct renesas_sdhi *priv;
714         int num_irqs, irq, ret, i;
715         struct resource *res;
716         u16 ver;
717
718         of_data = of_device_get_match_data(&pdev->dev);
719
720         attr = soc_device_match(sdhi_quirks_match);
721         if (attr)
722                 quirks = attr->data;
723
724         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
725         if (!res)
726                 return -EINVAL;
727
728         priv = devm_kzalloc(&pdev->dev, sizeof(struct renesas_sdhi),
729                             GFP_KERNEL);
730         if (!priv)
731                 return -ENOMEM;
732
733         priv->quirks = quirks;
734         mmc_data = &priv->mmc_data;
735         dma_priv = &priv->dma_priv;
736
737         priv->clk = devm_clk_get(&pdev->dev, NULL);
738         if (IS_ERR(priv->clk)) {
739                 ret = PTR_ERR(priv->clk);
740                 dev_err(&pdev->dev, "cannot get clock: %d\n", ret);
741                 return ret;
742         }
743
744         /*
745          * Some controllers provide a 2nd clock just to run the internal card
746          * detection logic. Unfortunately, the existing driver architecture does
747          * not support a separation of clocks for runtime PM usage. When
748          * native hotplug is used, the tmio driver assumes that the core
749          * must continue to run for card detect to stay active, so we cannot
750          * disable it.
751          * Additionally, it is prohibited to supply a clock to the core but not
752          * to the card detect circuit. That leaves us with if separate clocks
753          * are presented, we must treat them both as virtually 1 clock.
754          */
755         priv->clk_cd = devm_clk_get(&pdev->dev, "cd");
756         if (IS_ERR(priv->clk_cd))
757                 priv->clk_cd = NULL;
758
759         priv->pinctrl = devm_pinctrl_get(&pdev->dev);
760         if (!IS_ERR(priv->pinctrl)) {
761                 priv->pins_default = pinctrl_lookup_state(priv->pinctrl,
762                                                 PINCTRL_STATE_DEFAULT);
763                 priv->pins_uhs = pinctrl_lookup_state(priv->pinctrl,
764                                                 "state_uhs");
765         }
766
767         host = tmio_mmc_host_alloc(pdev, mmc_data);
768         if (IS_ERR(host))
769                 return PTR_ERR(host);
770
771         if (of_data) {
772                 mmc_data->flags |= of_data->tmio_flags;
773                 mmc_data->ocr_mask = of_data->tmio_ocr_mask;
774                 mmc_data->capabilities |= of_data->capabilities;
775                 mmc_data->capabilities2 |= of_data->capabilities2;
776                 mmc_data->dma_rx_offset = of_data->dma_rx_offset;
777                 mmc_data->max_blk_count = of_data->max_blk_count;
778                 mmc_data->max_segs = of_data->max_segs;
779                 dma_priv->dma_buswidth = of_data->dma_buswidth;
780                 host->bus_shift = of_data->bus_shift;
781         }
782
783         host->write16_hook      = renesas_sdhi_write16_hook;
784         host->clk_enable        = renesas_sdhi_clk_enable;
785         host->clk_disable       = renesas_sdhi_clk_disable;
786         host->set_clock         = renesas_sdhi_set_clock;
787         host->multi_io_quirk    = renesas_sdhi_multi_io_quirk;
788         host->dma_ops           = dma_ops;
789
790         if (quirks && quirks->hs400_disabled)
791                 host->mmc->caps2 &= ~(MMC_CAP2_HS400 | MMC_CAP2_HS400_ES);
792
793         /* For some SoC, we disable internal WP. GPIO may override this */
794         if (mmc_can_gpio_ro(host->mmc))
795                 mmc_data->capabilities2 &= ~MMC_CAP2_NO_WRITE_PROTECT;
796
797         /* SDR speeds are only available on Gen2+ */
798         if (mmc_data->flags & TMIO_MMC_MIN_RCAR2) {
799                 /* card_busy caused issues on r8a73a4 (pre-Gen2) CD-less SDHI */
800                 host->ops.card_busy = renesas_sdhi_card_busy;
801                 host->ops.start_signal_voltage_switch =
802                         renesas_sdhi_start_signal_voltage_switch;
803                 host->sdcard_irq_setbit_mask = TMIO_STAT_ALWAYS_SET_27;
804
805                 /* SDR and HS200/400 registers requires HW reset */
806                 if (of_data && of_data->scc_offset) {
807                         priv->scc_ctl = host->ctl + of_data->scc_offset;
808                         host->mmc->caps |= MMC_CAP_HW_RESET;
809                         host->hw_reset = renesas_sdhi_hw_reset;
810                 }
811         }
812
813         /* Orginally registers were 16 bit apart, could be 32 or 64 nowadays */
814         if (!host->bus_shift && resource_size(res) > 0x100) /* old way to determine the shift */
815                 host->bus_shift = 1;
816
817         if (mmd)
818                 *mmc_data = *mmd;
819
820         dma_priv->filter = shdma_chan_filter;
821         dma_priv->enable = renesas_sdhi_enable_dma;
822
823         mmc_data->alignment_shift = 1; /* 2-byte alignment */
824         mmc_data->capabilities |= MMC_CAP_MMC_HIGHSPEED;
825
826         /*
827          * All SDHI blocks support 2-byte and larger block sizes in 4-bit
828          * bus width mode.
829          */
830         mmc_data->flags |= TMIO_MMC_BLKSZ_2BYTES;
831
832         /*
833          * All SDHI blocks support SDIO IRQ signalling.
834          */
835         mmc_data->flags |= TMIO_MMC_SDIO_IRQ;
836
837         /* All SDHI have CMD12 control bit */
838         mmc_data->flags |= TMIO_MMC_HAVE_CMD12_CTRL;
839
840         /* All SDHI have SDIO status bits which must be 1 */
841         mmc_data->flags |= TMIO_MMC_SDIO_STATUS_SETBITS;
842
843         ret = renesas_sdhi_clk_enable(host);
844         if (ret)
845                 goto efree;
846
847         ver = sd_ctrl_read16(host, CTL_VERSION);
848         /* GEN2_SDR104 is first known SDHI to use 32bit block count */
849         if (ver < SDHI_VER_GEN2_SDR104 && mmc_data->max_blk_count > U16_MAX)
850                 mmc_data->max_blk_count = U16_MAX;
851
852         /* One Gen2 SDHI incarnation does NOT have a CBSY bit */
853         if (ver == SDHI_VER_GEN2_SDR50)
854                 mmc_data->flags &= ~TMIO_MMC_HAVE_CBSY;
855
856         ret = tmio_mmc_host_probe(host);
857         if (ret < 0)
858                 goto edisclk;
859
860         /* Enable tuning iff we have an SCC and a supported mode */
861         if (of_data && of_data->scc_offset &&
862             (host->mmc->caps & MMC_CAP_UHS_SDR104 ||
863              host->mmc->caps2 & (MMC_CAP2_HS200_1_8V_SDR |
864                                  MMC_CAP2_HS400_1_8V))) {
865                 const struct renesas_sdhi_scc *taps = of_data->taps;
866                 bool use_4tap = priv->quirks && priv->quirks->hs400_4taps;
867                 bool hit = false;
868
869                 for (i = 0; i < of_data->taps_num; i++) {
870                         if (taps[i].clk_rate == 0 ||
871                             taps[i].clk_rate == host->mmc->f_max) {
872                                 priv->scc_tappos = taps->tap;
873                                 priv->scc_tappos_hs400 = use_4tap ?
874                                                          taps->tap_hs400_4tap :
875                                                          taps->tap;
876                                 hit = true;
877                                 break;
878                         }
879                 }
880
881                 if (!hit)
882                         dev_warn(&host->pdev->dev, "Unknown clock rate for tuning\n");
883
884                 host->execute_tuning = renesas_sdhi_execute_tuning;
885                 host->check_retune = renesas_sdhi_check_scc_error;
886                 host->ops.prepare_hs400_tuning = renesas_sdhi_prepare_hs400_tuning;
887                 host->ops.hs400_downgrade = renesas_sdhi_disable_scc;
888                 host->ops.hs400_complete = renesas_sdhi_hs400_complete;
889         }
890
891         num_irqs = platform_irq_count(pdev);
892         if (num_irqs < 0) {
893                 ret = num_irqs;
894                 goto eirq;
895         }
896
897         /* There must be at least one IRQ source */
898         if (!num_irqs) {
899                 ret = -ENXIO;
900                 goto eirq;
901         }
902
903         for (i = 0; i < num_irqs; i++) {
904                 irq = platform_get_irq(pdev, i);
905                 if (irq < 0) {
906                         ret = irq;
907                         goto eirq;
908                 }
909
910                 ret = devm_request_irq(&pdev->dev, irq, tmio_mmc_irq, 0,
911                                        dev_name(&pdev->dev), host);
912                 if (ret)
913                         goto eirq;
914         }
915
916         dev_info(&pdev->dev, "%s base at 0x%08lx max clock rate %u MHz\n",
917                  mmc_hostname(host->mmc), (unsigned long)
918                  (platform_get_resource(pdev, IORESOURCE_MEM, 0)->start),
919                  host->mmc->f_max / 1000000);
920
921         return ret;
922
923 eirq:
924         tmio_mmc_host_remove(host);
925 edisclk:
926         renesas_sdhi_clk_disable(host);
927 efree:
928         tmio_mmc_host_free(host);
929
930         return ret;
931 }
932 EXPORT_SYMBOL_GPL(renesas_sdhi_probe);
933
934 int renesas_sdhi_remove(struct platform_device *pdev)
935 {
936         struct tmio_mmc_host *host = platform_get_drvdata(pdev);
937
938         tmio_mmc_host_remove(host);
939         renesas_sdhi_clk_disable(host);
940
941         return 0;
942 }
943 EXPORT_SYMBOL_GPL(renesas_sdhi_remove);
944
945 MODULE_LICENSE("GPL v2");