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"); 549