drivers/mmc/host/dw_mmc-exynos.c

   1 /*
   2  * Exynos Specific Extensions for Synopsys DW Multimedia Card Interface driver
   3  *
   4  * Copyright (C) 2012, Samsung Electronics Co., Ltd.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/clk.h>
  15 #include <linux/mmc/host.h>
  16 #include <linux/mmc/dw_mmc.h>
  17 #include <linux/mmc/mmc.h>
  18 #include <linux/of.h>
  19 #include <linux/of_gpio.h>
  20 #include <linux/slab.h>
  21
  22 #include "dw_mmc.h"
  23 #include "dw_mmc-pltfm.h"
  24 #include "dw_mmc-exynos.h"
  25
  26 /* Variations in Exynos specific dw-mshc controller */
  27 enum dw_mci_exynos_type {
  28         DW_MCI_TYPE_EXYNOS4210,
  29         DW_MCI_TYPE_EXYNOS4412,
  30         DW_MCI_TYPE_EXYNOS5250,
  31         DW_MCI_TYPE_EXYNOS5420,
  32         DW_MCI_TYPE_EXYNOS5420_SMU,
  33         DW_MCI_TYPE_EXYNOS7,
  34         DW_MCI_TYPE_EXYNOS7_SMU,
  35 };
  36
  37 /* Exynos implementation specific driver private data */
  38 struct dw_mci_exynos_priv_data {
  39         enum dw_mci_exynos_type         ctrl_type;
  40         u8                              ciu_div;
  41         u32                             sdr_timing;
  42         u32                             ddr_timing;
  43         u32                             hs400_timing;
  44         u32                             tuned_sample;
  45         u32                             cur_speed;
  46         u32                             dqs_delay;
  47         u32                             saved_dqs_en;
  48         u32                             saved_strobe_ctrl;
  49 };
  50
  51 static struct dw_mci_exynos_compatible {
  52         char                            *compatible;
  53         enum dw_mci_exynos_type         ctrl_type;
  54 } exynos_compat[] = {
  55         {
  56                 .compatible     = "samsung,exynos4210-dw-mshc",
  57                 .ctrl_type      = DW_MCI_TYPE_EXYNOS4210,
  58         }, {
  59                 .compatible     = "samsung,exynos4412-dw-mshc",
  60                 .ctrl_type      = DW_MCI_TYPE_EXYNOS4412,
  61         }, {
  62                 .compatible     = "samsung,exynos5250-dw-mshc",
  63                 .ctrl_type      = DW_MCI_TYPE_EXYNOS5250,
  64         }, {
  65                 .compatible     = "samsung,exynos5420-dw-mshc",
  66                 .ctrl_type      = DW_MCI_TYPE_EXYNOS5420,
  67         }, {
  68                 .compatible     = "samsung,exynos5420-dw-mshc-smu",
  69                 .ctrl_type      = DW_MCI_TYPE_EXYNOS5420_SMU,
  70         }, {
  71                 .compatible     = "samsung,exynos7-dw-mshc",
  72                 .ctrl_type      = DW_MCI_TYPE_EXYNOS7,
  73         }, {
  74                 .compatible     = "samsung,exynos7-dw-mshc-smu",
  75                 .ctrl_type      = DW_MCI_TYPE_EXYNOS7_SMU,
  76         },
  77 };
  78
  79 static inline u8 dw_mci_exynos_get_ciu_div(struct dw_mci *host)
  80 {
  81         struct dw_mci_exynos_priv_data *priv = host->priv;
  82
  83         if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
  84                 return EXYNOS4412_FIXED_CIU_CLK_DIV;
  85         else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
  86                 return EXYNOS4210_FIXED_CIU_CLK_DIV;
  87         else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
  88                         priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
  89                 return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL64)) + 1;
  90         else
  91                 return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL)) + 1;
  92 }
  93
  94 static int dw_mci_exynos_priv_init(struct dw_mci *host)
  95 {
  96         struct dw_mci_exynos_priv_data *priv = host->priv;
  97
  98         if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS5420_SMU ||
  99                 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU) {
 100                 mci_writel(host, MPSBEGIN0, 0);
 101                 mci_writel(host, MPSEND0, SDMMC_ENDING_SEC_NR_MAX);
 102                 mci_writel(host, MPSCTRL0, SDMMC_MPSCTRL_SECURE_WRITE_BIT |
 103                            SDMMC_MPSCTRL_NON_SECURE_READ_BIT |
 104                            SDMMC_MPSCTRL_VALID |
 105                            SDMMC_MPSCTRL_NON_SECURE_WRITE_BIT);
 106         }
 107
 108         if (priv->ctrl_type >= DW_MCI_TYPE_EXYNOS5420) {
 109                 priv->saved_strobe_ctrl = mci_readl(host, HS400_DLINE_CTRL);
 110                 priv->saved_dqs_en = mci_readl(host, HS400_DQS_EN);
 111                 priv->saved_dqs_en |= AXI_NON_BLOCKING_WR;
 112                 mci_writel(host, HS400_DQS_EN, priv->saved_dqs_en);
 113                 if (!priv->dqs_delay)
 114                         priv->dqs_delay =
 115                                 DQS_CTRL_GET_RD_DELAY(priv->saved_strobe_ctrl);
 116         }
 117
 118         return 0;
 119 }
 120
 121 static int dw_mci_exynos_setup_clock(struct dw_mci *host)
 122 {
 123         struct dw_mci_exynos_priv_data *priv = host->priv;
 124
 125         host->bus_hz /= (priv->ciu_div + 1);
 126
 127         return 0;
 128 }
 129
 130 static void dw_mci_exynos_set_clksel_timing(struct dw_mci *host, u32 timing)
 131 {
 132         struct dw_mci_exynos_priv_data *priv = host->priv;
 133         u32 clksel;
 134
 135         if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 136                 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
 137                 clksel = mci_readl(host, CLKSEL64);
 138         else
 139                 clksel = mci_readl(host, CLKSEL);
 140
 141         clksel = (clksel & ~SDMMC_CLKSEL_TIMING_MASK) | timing;
 142
 143         if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 144                 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
 145                 mci_writel(host, CLKSEL64, clksel);
 146         else
 147                 mci_writel(host, CLKSEL, clksel);
 148
 149         /*
 150          * Exynos4412 and Exynos5250 extends the use of CMD register with the
 151          * use of bit 29 (which is reserved on standard MSHC controllers) for
 152          * optionally bypassing the HOLD register for command and data. The
 153          * HOLD register should be bypassed in case there is no phase shift
 154          * applied on CMD/DATA that is sent to the card.
 155          */
 156         if (!SDMMC_CLKSEL_GET_DRV_WD3(clksel))
 157                 set_bit(DW_MMC_CARD_NO_USE_HOLD, &host->cur_slot->flags);
 158 }
 159
 160 #ifdef CONFIG_PM_SLEEP
 161 static int dw_mci_exynos_suspend(struct device *dev)
 162 {
 163         struct dw_mci *host = dev_get_drvdata(dev);
 164
 165         return dw_mci_suspend(host);
 166 }
 167
 168 static int dw_mci_exynos_resume(struct device *dev)
 169 {
 170         struct dw_mci *host = dev_get_drvdata(dev);
 171
 172         dw_mci_exynos_priv_init(host);
 173         return dw_mci_resume(host);
 174 }
 175
 176 /**
 177  * dw_mci_exynos_resume_noirq - Exynos-specific resume code
 178  *
 179  * On exynos5420 there is a silicon errata that will sometimes leave the
 180  * WAKEUP_INT bit in the CLKSEL register asserted.  This bit is 1 to indicate
 181  * that it fired and we can clear it by writing a 1 back.  Clear it to prevent
 182  * interrupts from going off constantly.
 183  *
 184  * We run this code on all exynos variants because it doesn't hurt.
 185  */
 186
 187 static int dw_mci_exynos_resume_noirq(struct device *dev)
 188 {
 189         struct dw_mci *host = dev_get_drvdata(dev);
 190         struct dw_mci_exynos_priv_data *priv = host->priv;
 191         u32 clksel;
 192
 193         if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 194                 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
 195                 clksel = mci_readl(host, CLKSEL64);
 196         else
 197                 clksel = mci_readl(host, CLKSEL);
 198
 199         if (clksel & SDMMC_CLKSEL_WAKEUP_INT) {
 200                 if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 201                         priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
 202                         mci_writel(host, CLKSEL64, clksel);
 203                 else
 204                         mci_writel(host, CLKSEL, clksel);
 205         }
 206
 207         return 0;
 208 }
 209 #else
 210 #define dw_mci_exynos_suspend           NULL
 211 #define dw_mci_exynos_resume            NULL
 212 #define dw_mci_exynos_resume_noirq      NULL
 213 #endif /* CONFIG_PM_SLEEP */
 214
 215 static void dw_mci_exynos_config_hs400(struct dw_mci *host, u32 timing)
 216 {
 217         struct dw_mci_exynos_priv_data *priv = host->priv;
 218         u32 dqs, strobe;
 219
 220         /*
 221          * Not supported to configure register
 222          * related to HS400
 223          */
 224         if (priv->ctrl_type < DW_MCI_TYPE_EXYNOS5420)
 225                 return;
 226
 227         dqs = priv->saved_dqs_en;
 228         strobe = priv->saved_strobe_ctrl;
 229
 230         if (timing == MMC_TIMING_MMC_HS400) {
 231                 dqs |= DATA_STROBE_EN;
 232                 strobe = DQS_CTRL_RD_DELAY(strobe, priv->dqs_delay);
 233         } else {
 234                 dqs &= ~DATA_STROBE_EN;
 235         }
 236
 237         mci_writel(host, HS400_DQS_EN, dqs);
 238         mci_writel(host, HS400_DLINE_CTRL, strobe);
 239 }
 240
 241 static void dw_mci_exynos_adjust_clock(struct dw_mci *host, unsigned int wanted)
 242 {
 243         struct dw_mci_exynos_priv_data *priv = host->priv;
 244         unsigned long actual;
 245         u8 div;
 246         int ret;
 247         /*
 248          * Don't care if wanted clock is zero or
 249          * ciu clock is unavailable
 250          */
 251         if (!wanted || IS_ERR(host->ciu_clk))
 252                 return;
 253
 254         /* Guaranteed minimum frequency for cclkin */
 255         if (wanted < EXYNOS_CCLKIN_MIN)
 256                 wanted = EXYNOS_CCLKIN_MIN;
 257
 258         if (wanted == priv->cur_speed)
 259                 return;
 260
 261         div = dw_mci_exynos_get_ciu_div(host);
 262         ret = clk_set_rate(host->ciu_clk, wanted * div);
 263         if (ret)
 264                 dev_warn(host->dev,
 265                         "failed to set clk-rate %u error: %d\n",
 266                         wanted * div, ret);
 267         actual = clk_get_rate(host->ciu_clk);
 268         host->bus_hz = actual / div;
 269         priv->cur_speed = wanted;
 270         host->current_speed = 0;
 271 }
 272
 273 static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
 274 {
 275         struct dw_mci_exynos_priv_data *priv = host->priv;
 276         unsigned int wanted = ios->clock;
 277         u32 timing = ios->timing, clksel;
 278
 279         switch (timing) {
 280         case MMC_TIMING_MMC_HS400:
 281                 /* Update tuned sample timing */
 282                 clksel = SDMMC_CLKSEL_UP_SAMPLE(
 283                                 priv->hs400_timing, priv->tuned_sample);
 284                 wanted <<= 1;
 285                 break;
 286         case MMC_TIMING_MMC_DDR52:
 287                 clksel = priv->ddr_timing;
 288                 /* Should be double rate for DDR mode */
 289                 if (ios->bus_width == MMC_BUS_WIDTH_8)
 290                         wanted <<= 1;
 291                 break;
 292         default:
 293                 clksel = priv->sdr_timing;
 294         }
 295
 296         /* Set clock timing for the requested speed mode*/
 297         dw_mci_exynos_set_clksel_timing(host, clksel);
 298
 299         /* Configure setting for HS400 */
 300         dw_mci_exynos_config_hs400(host, timing);
 301
 302         /* Configure clock rate */
 303         dw_mci_exynos_adjust_clock(host, wanted);
 304 }
 305
 306 static int dw_mci_exynos_parse_dt(struct dw_mci *host)
 307 {
 308         struct dw_mci_exynos_priv_data *priv;
 309         struct device_node *np = host->dev->of_node;
 310         u32 timing[2];
 311         u32 div = 0;
 312         int idx;
 313         int ret;
 314
 315         priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
 316         if (!priv)
 317                 return -ENOMEM;
 318
 319         for (idx = 0; idx < ARRAY_SIZE(exynos_compat); idx++) {
 320                 if (of_device_is_compatible(np, exynos_compat[idx].compatible))
 321                         priv->ctrl_type = exynos_compat[idx].ctrl_type;
 322         }
 323
 324         if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
 325                 priv->ciu_div = EXYNOS4412_FIXED_CIU_CLK_DIV - 1;
 326         else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
 327                 priv->ciu_div = EXYNOS4210_FIXED_CIU_CLK_DIV - 1;
 328         else {
 329                 of_property_read_u32(np, "samsung,dw-mshc-ciu-div", &div);
 330                 priv->ciu_div = div;
 331         }
 332
 333         ret = of_property_read_u32_array(np,
 334                         "samsung,dw-mshc-sdr-timing", timing, 2);
 335         if (ret)
 336                 return ret;
 337
 338         priv->sdr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
 339
 340         ret = of_property_read_u32_array(np,
 341                         "samsung,dw-mshc-ddr-timing", timing, 2);
 342         if (ret)
 343                 return ret;
 344
 345         priv->ddr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
 346
 347         ret = of_property_read_u32_array(np,
 348                         "samsung,dw-mshc-hs400-timing", timing, 2);
 349         if (!ret && of_property_read_u32(np,
 350                                 "samsung,read-strobe-delay", &priv->dqs_delay))
 351                 dev_dbg(host->dev,
 352                         "read-strobe-delay is not found, assuming usage of default value\n");
 353
 354         priv->hs400_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1],
 355                                                 HS400_FIXED_CIU_CLK_DIV);
 356         host->priv = priv;
 357         return 0;
 358 }
 359
 360 static inline u8 dw_mci_exynos_get_clksmpl(struct dw_mci *host)
 361 {
 362         struct dw_mci_exynos_priv_data *priv = host->priv;
 363
 364         if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 365                 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
 366                 return SDMMC_CLKSEL_CCLK_SAMPLE(mci_readl(host, CLKSEL64));
 367         else
 368                 return SDMMC_CLKSEL_CCLK_SAMPLE(mci_readl(host, CLKSEL));
 369 }
 370
 371 static inline void dw_mci_exynos_set_clksmpl(struct dw_mci *host, u8 sample)
 372 {
 373         u32 clksel;
 374         struct dw_mci_exynos_priv_data *priv = host->priv;
 375
 376         if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 377                 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
 378                 clksel = mci_readl(host, CLKSEL64);
 379         else
 380                 clksel = mci_readl(host, CLKSEL);
 381         clksel = SDMMC_CLKSEL_UP_SAMPLE(clksel, sample);
 382         if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 383                 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
 384                 mci_writel(host, CLKSEL64, clksel);
 385         else
 386                 mci_writel(host, CLKSEL, clksel);
 387 }
 388
 389 static inline u8 dw_mci_exynos_move_next_clksmpl(struct dw_mci *host)
 390 {
 391         struct dw_mci_exynos_priv_data *priv = host->priv;
 392         u32 clksel;
 393         u8 sample;
 394
 395         if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 396                 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
 397                 clksel = mci_readl(host, CLKSEL64);
 398         else
 399                 clksel = mci_readl(host, CLKSEL);
 400
 401         sample = (clksel + 1) & 0x7;
 402         clksel = SDMMC_CLKSEL_UP_SAMPLE(clksel, sample);
 403
 404         if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 405                 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
 406                 mci_writel(host, CLKSEL64, clksel);
 407         else
 408                 mci_writel(host, CLKSEL, clksel);
 409
 410         return sample;
 411 }
 412
 413 static s8 dw_mci_exynos_get_best_clksmpl(u8 candiates)
 414 {
 415         const u8 iter = 8;
 416         u8 __c;
 417         s8 i, loc = -1;
 418
 419         for (i = 0; i < iter; i++) {
 420                 __c = ror8(candiates, i);
 421                 if ((__c & 0xc7) == 0xc7) {
 422                         loc = i;
 423                         goto out;
 424                 }
 425         }
 426
 427         for (i = 0; i < iter; i++) {
 428                 __c = ror8(candiates, i);
 429                 if ((__c & 0x83) == 0x83) {
 430                         loc = i;
 431                         goto out;
 432                 }
 433         }
 434
 435 out:
 436         return loc;
 437 }
 438
 439 static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot, u32 opcode)
 440 {
 441         struct dw_mci *host = slot->host;
 442         struct dw_mci_exynos_priv_data *priv = host->priv;
 443         struct mmc_host *mmc = slot->mmc;
 444         u8 start_smpl, smpl, candiates = 0;
 445         s8 found = -1;
 446         int ret = 0;
 447
 448         start_smpl = dw_mci_exynos_get_clksmpl(host);
 449
 450         do {
 451                 mci_writel(host, TMOUT, ~0);
 452                 smpl = dw_mci_exynos_move_next_clksmpl(host);
 453
 454                 if (!mmc_send_tuning(mmc, opcode, NULL))
 455                         candiates |= (1 << smpl);
 456
 457         } while (start_smpl != smpl);
 458
 459         found = dw_mci_exynos_get_best_clksmpl(candiates);
 460         if (found >= 0) {
 461                 dw_mci_exynos_set_clksmpl(host, found);
 462                 priv->tuned_sample = found;
 463         } else {
 464                 ret = -EIO;
 465         }
 466
 467         return ret;
 468 }
 469
 470 static int dw_mci_exynos_prepare_hs400_tuning(struct dw_mci *host,
 471                                         struct mmc_ios *ios)
 472 {
 473         struct dw_mci_exynos_priv_data *priv = host->priv;
 474
 475         dw_mci_exynos_set_clksel_timing(host, priv->hs400_timing);
 476         dw_mci_exynos_adjust_clock(host, (ios->clock) << 1);
 477
 478         return 0;
 479 }
 480
 481 /* Common capabilities of Exynos4/Exynos5 SoC */
 482 static unsigned long exynos_dwmmc_caps[4] = {
 483         MMC_CAP_1_8V_DDR | MMC_CAP_8_BIT_DATA | MMC_CAP_CMD23,
 484         MMC_CAP_CMD23,
 485         MMC_CAP_CMD23,
 486         MMC_CAP_CMD23,
 487 };
 488
 489 static const struct dw_mci_drv_data exynos_drv_data = {
 490         .caps                   = exynos_dwmmc_caps,
 491         .init                   = dw_mci_exynos_priv_init,
 492         .setup_clock            = dw_mci_exynos_setup_clock,
 493         .set_ios                = dw_mci_exynos_set_ios,
 494         .parse_dt               = dw_mci_exynos_parse_dt,
 495         .execute_tuning         = dw_mci_exynos_execute_tuning,
 496         .prepare_hs400_tuning   = dw_mci_exynos_prepare_hs400_tuning,
 497 };
 498
 499 static const struct of_device_id dw_mci_exynos_match[] = {
 500         { .compatible = "samsung,exynos4412-dw-mshc",
 501                         .data = &exynos_drv_data, },
 502         { .compatible = "samsung,exynos5250-dw-mshc",
 503                         .data = &exynos_drv_data, },
 504         { .compatible = "samsung,exynos5420-dw-mshc",
 505                         .data = &exynos_drv_data, },
 506         { .compatible = "samsung,exynos5420-dw-mshc-smu",
 507                         .data = &exynos_drv_data, },
 508         { .compatible = "samsung,exynos7-dw-mshc",
 509                         .data = &exynos_drv_data, },
 510         { .compatible = "samsung,exynos7-dw-mshc-smu",
 511                         .data = &exynos_drv_data, },
 512         {},
 513 };
 514 MODULE_DEVICE_TABLE(of, dw_mci_exynos_match);
 515
 516 static int dw_mci_exynos_probe(struct platform_device *pdev)
 517 {
 518         const struct dw_mci_drv_data *drv_data;
 519         const struct of_device_id *match;
 520
 521         match = of_match_node(dw_mci_exynos_match, pdev->dev.of_node);
 522         drv_data = match->data;
 523         return dw_mci_pltfm_register(pdev, drv_data);
 524 }
 525
 526 static const struct dev_pm_ops dw_mci_exynos_pmops = {
 527         SET_SYSTEM_SLEEP_PM_OPS(dw_mci_exynos_suspend, dw_mci_exynos_resume)
 528         .resume_noirq = dw_mci_exynos_resume_noirq,
 529         .thaw_noirq = dw_mci_exynos_resume_noirq,
 530         .restore_noirq = dw_mci_exynos_resume_noirq,
 531 };
 532
 533 static struct platform_driver dw_mci_exynos_pltfm_driver = {
 534         .probe          = dw_mci_exynos_probe,
 535         .remove         = dw_mci_pltfm_remove,
 536         .driver         = {
 537                 .name           = "dwmmc_exynos",
 538                 .of_match_table = dw_mci_exynos_match,
 539                 .pm             = &dw_mci_exynos_pmops,
 540         },
 541 };
 542
 543 module_platform_driver(dw_mci_exynos_pltfm_driver);
 544
 545 MODULE_DESCRIPTION("Samsung Specific DW-MSHC Driver Extension");
 546 MODULE_AUTHOR("Thomas Abraham <thomas.ab@samsung.com");
 547 MODULE_LICENSE("GPL v2");
 548 MODULE_ALIAS("platform:dwmmc_exynos");