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 #ifdef CONFIG_PM_SLEEP 151 static int dw_mci_exynos_suspend(struct device *dev) 152 { 153 struct dw_mci *host = dev_get_drvdata(dev); 154 155 return dw_mci_suspend(host); 156 } 157 158 static int dw_mci_exynos_resume(struct device *dev) 159 { 160 struct dw_mci *host = dev_get_drvdata(dev); 161 162 dw_mci_exynos_priv_init(host); 163 return dw_mci_resume(host); 164 } 165 166 /** 167 * dw_mci_exynos_resume_noirq - Exynos-specific resume code 168 * 169 * On exynos5420 there is a silicon errata that will sometimes leave the 170 * WAKEUP_INT bit in the CLKSEL register asserted. This bit is 1 to indicate 171 * that it fired and we can clear it by writing a 1 back. Clear it to prevent 172 * interrupts from going off constantly. 173 * 174 * We run this code on all exynos variants because it doesn't hurt. 175 */ 176 177 static int dw_mci_exynos_resume_noirq(struct device *dev) 178 { 179 struct dw_mci *host = dev_get_drvdata(dev); 180 struct dw_mci_exynos_priv_data *priv = host->priv; 181 u32 clksel; 182 183 if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 || 184 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU) 185 clksel = mci_readl(host, CLKSEL64); 186 else 187 clksel = mci_readl(host, CLKSEL); 188 189 if (clksel & SDMMC_CLKSEL_WAKEUP_INT) { 190 if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 || 191 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU) 192 mci_writel(host, CLKSEL64, clksel); 193 else 194 mci_writel(host, CLKSEL, clksel); 195 } 196 197 return 0; 198 } 199 #else 200 #define dw_mci_exynos_suspend NULL 201 #define dw_mci_exynos_resume NULL 202 #define dw_mci_exynos_resume_noirq NULL 203 #endif /* CONFIG_PM_SLEEP */ 204 205 static void dw_mci_exynos_prepare_command(struct dw_mci *host, u32 *cmdr) 206 { 207 struct dw_mci_exynos_priv_data *priv = host->priv; 208 /* 209 * Exynos4412 and Exynos5250 extends the use of CMD register with the 210 * use of bit 29 (which is reserved on standard MSHC controllers) for 211 * optionally bypassing the HOLD register for command and data. The 212 * HOLD register should be bypassed in case there is no phase shift 213 * applied on CMD/DATA that is sent to the card. 214 */ 215 if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 || 216 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU) { 217 if (SDMMC_CLKSEL_GET_DRV_WD3(mci_readl(host, CLKSEL64))) 218 *cmdr |= SDMMC_CMD_USE_HOLD_REG; 219 } else { 220 if (SDMMC_CLKSEL_GET_DRV_WD3(mci_readl(host, CLKSEL))) 221 *cmdr |= SDMMC_CMD_USE_HOLD_REG; 222 } 223 } 224 225 static void dw_mci_exynos_config_hs400(struct dw_mci *host, u32 timing) 226 { 227 struct dw_mci_exynos_priv_data *priv = host->priv; 228 u32 dqs, strobe; 229 230 /* 231 * Not supported to configure register 232 * related to HS400 233 */ 234 if (priv->ctrl_type < DW_MCI_TYPE_EXYNOS5420) 235 return; 236 237 dqs = priv->saved_dqs_en; 238 strobe = priv->saved_strobe_ctrl; 239 240 if (timing == MMC_TIMING_MMC_HS400) { 241 dqs |= DATA_STROBE_EN; 242 strobe = DQS_CTRL_RD_DELAY(strobe, priv->dqs_delay); 243 } else { 244 dqs &= ~DATA_STROBE_EN; 245 } 246 247 mci_writel(host, HS400_DQS_EN, dqs); 248 mci_writel(host, HS400_DLINE_CTRL, strobe); 249 } 250 251 static void dw_mci_exynos_adjust_clock(struct dw_mci *host, unsigned int wanted) 252 { 253 struct dw_mci_exynos_priv_data *priv = host->priv; 254 unsigned long actual; 255 u8 div; 256 int ret; 257 /* 258 * Don't care if wanted clock is zero or 259 * ciu clock is unavailable 260 */ 261 if (!wanted || IS_ERR(host->ciu_clk)) 262 return; 263 264 /* Guaranteed minimum frequency for cclkin */ 265 if (wanted < EXYNOS_CCLKIN_MIN) 266 wanted = EXYNOS_CCLKIN_MIN; 267 268 if (wanted == priv->cur_speed) 269 return; 270 271 div = dw_mci_exynos_get_ciu_div(host); 272 ret = clk_set_rate(host->ciu_clk, wanted * div); 273 if (ret) 274 dev_warn(host->dev, 275 "failed to set clk-rate %u error: %d\n", 276 wanted * div, ret); 277 actual = clk_get_rate(host->ciu_clk); 278 host->bus_hz = actual / div; 279 priv->cur_speed = wanted; 280 host->current_speed = 0; 281 } 282 283 static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios) 284 { 285 struct dw_mci_exynos_priv_data *priv = host->priv; 286 unsigned int wanted = ios->clock; 287 u32 timing = ios->timing, clksel; 288 289 switch (timing) { 290 case MMC_TIMING_MMC_HS400: 291 /* Update tuned sample timing */ 292 clksel = SDMMC_CLKSEL_UP_SAMPLE( 293 priv->hs400_timing, priv->tuned_sample); 294 wanted <<= 1; 295 break; 296 case MMC_TIMING_MMC_DDR52: 297 clksel = priv->ddr_timing; 298 /* Should be double rate for DDR mode */ 299 if (ios->bus_width == MMC_BUS_WIDTH_8) 300 wanted <<= 1; 301 break; 302 default: 303 clksel = priv->sdr_timing; 304 } 305 306 /* Set clock timing for the requested speed mode*/ 307 dw_mci_exynos_set_clksel_timing(host, clksel); 308 309 /* Configure setting for HS400 */ 310 dw_mci_exynos_config_hs400(host, timing); 311 312 /* Configure clock rate */ 313 dw_mci_exynos_adjust_clock(host, wanted); 314 } 315 316 static int dw_mci_exynos_parse_dt(struct dw_mci *host) 317 { 318 struct dw_mci_exynos_priv_data *priv; 319 struct device_node *np = host->dev->of_node; 320 u32 timing[2]; 321 u32 div = 0; 322 int idx; 323 int ret; 324 325 priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL); 326 if (!priv) 327 return -ENOMEM; 328 329 for (idx = 0; idx < ARRAY_SIZE(exynos_compat); idx++) { 330 if (of_device_is_compatible(np, exynos_compat[idx].compatible)) 331 priv->ctrl_type = exynos_compat[idx].ctrl_type; 332 } 333 334 if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412) 335 priv->ciu_div = EXYNOS4412_FIXED_CIU_CLK_DIV - 1; 336 else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210) 337 priv->ciu_div = EXYNOS4210_FIXED_CIU_CLK_DIV - 1; 338 else { 339 of_property_read_u32(np, "samsung,dw-mshc-ciu-div", &div); 340 priv->ciu_div = div; 341 } 342 343 ret = of_property_read_u32_array(np, 344 "samsung,dw-mshc-sdr-timing", timing, 2); 345 if (ret) 346 return ret; 347 348 priv->sdr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div); 349 350 ret = of_property_read_u32_array(np, 351 "samsung,dw-mshc-ddr-timing", timing, 2); 352 if (ret) 353 return ret; 354 355 priv->ddr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div); 356 357 ret = of_property_read_u32_array(np, 358 "samsung,dw-mshc-hs400-timing", timing, 2); 359 if (!ret && of_property_read_u32(np, 360 "samsung,read-strobe-delay", &priv->dqs_delay)) 361 dev_dbg(host->dev, 362 "read-strobe-delay is not found, assuming usage of default value\n"); 363 364 priv->hs400_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], 365 HS400_FIXED_CIU_CLK_DIV); 366 host->priv = priv; 367 return 0; 368 } 369 370 static inline u8 dw_mci_exynos_get_clksmpl(struct dw_mci *host) 371 { 372 struct dw_mci_exynos_priv_data *priv = host->priv; 373 374 if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 || 375 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU) 376 return SDMMC_CLKSEL_CCLK_SAMPLE(mci_readl(host, CLKSEL64)); 377 else 378 return SDMMC_CLKSEL_CCLK_SAMPLE(mci_readl(host, CLKSEL)); 379 } 380 381 static inline void dw_mci_exynos_set_clksmpl(struct dw_mci *host, u8 sample) 382 { 383 u32 clksel; 384 struct dw_mci_exynos_priv_data *priv = host->priv; 385 386 if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 || 387 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU) 388 clksel = mci_readl(host, CLKSEL64); 389 else 390 clksel = mci_readl(host, CLKSEL); 391 clksel = SDMMC_CLKSEL_UP_SAMPLE(clksel, sample); 392 if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 || 393 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU) 394 mci_writel(host, CLKSEL64, clksel); 395 else 396 mci_writel(host, CLKSEL, clksel); 397 } 398 399 static inline u8 dw_mci_exynos_move_next_clksmpl(struct dw_mci *host) 400 { 401 struct dw_mci_exynos_priv_data *priv = host->priv; 402 u32 clksel; 403 u8 sample; 404 405 if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 || 406 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU) 407 clksel = mci_readl(host, CLKSEL64); 408 else 409 clksel = mci_readl(host, CLKSEL); 410 411 sample = (clksel + 1) & 0x7; 412 clksel = SDMMC_CLKSEL_UP_SAMPLE(clksel, sample); 413 414 if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 || 415 priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU) 416 mci_writel(host, CLKSEL64, clksel); 417 else 418 mci_writel(host, CLKSEL, clksel); 419 420 return sample; 421 } 422 423 static s8 dw_mci_exynos_get_best_clksmpl(u8 candiates) 424 { 425 const u8 iter = 8; 426 u8 __c; 427 s8 i, loc = -1; 428 429 for (i = 0; i < iter; i++) { 430 __c = ror8(candiates, i); 431 if ((__c & 0xc7) == 0xc7) { 432 loc = i; 433 goto out; 434 } 435 } 436 437 for (i = 0; i < iter; i++) { 438 __c = ror8(candiates, i); 439 if ((__c & 0x83) == 0x83) { 440 loc = i; 441 goto out; 442 } 443 } 444 445 out: 446 return loc; 447 } 448 449 static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot) 450 { 451 struct dw_mci *host = slot->host; 452 struct dw_mci_exynos_priv_data *priv = host->priv; 453 struct mmc_host *mmc = slot->mmc; 454 u8 start_smpl, smpl, candiates = 0; 455 s8 found = -1; 456 int ret = 0; 457 458 start_smpl = dw_mci_exynos_get_clksmpl(host); 459 460 do { 461 mci_writel(host, TMOUT, ~0); 462 smpl = dw_mci_exynos_move_next_clksmpl(host); 463 464 if (!mmc_send_tuning(mmc)) 465 candiates |= (1 << smpl); 466 467 } while (start_smpl != smpl); 468 469 found = dw_mci_exynos_get_best_clksmpl(candiates); 470 if (found >= 0) { 471 dw_mci_exynos_set_clksmpl(host, found); 472 priv->tuned_sample = found; 473 } else { 474 ret = -EIO; 475 } 476 477 return ret; 478 } 479 480 static int dw_mci_exynos_prepare_hs400_tuning(struct dw_mci *host, 481 struct mmc_ios *ios) 482 { 483 struct dw_mci_exynos_priv_data *priv = host->priv; 484 485 dw_mci_exynos_set_clksel_timing(host, priv->hs400_timing); 486 dw_mci_exynos_adjust_clock(host, (ios->clock) << 1); 487 488 return 0; 489 } 490 491 /* Common capabilities of Exynos4/Exynos5 SoC */ 492 static unsigned long exynos_dwmmc_caps[4] = { 493 MMC_CAP_1_8V_DDR | MMC_CAP_8_BIT_DATA | MMC_CAP_CMD23, 494 MMC_CAP_CMD23, 495 MMC_CAP_CMD23, 496 MMC_CAP_CMD23, 497 }; 498 499 static const struct dw_mci_drv_data exynos_drv_data = { 500 .caps = exynos_dwmmc_caps, 501 .init = dw_mci_exynos_priv_init, 502 .setup_clock = dw_mci_exynos_setup_clock, 503 .prepare_command = dw_mci_exynos_prepare_command, 504 .set_ios = dw_mci_exynos_set_ios, 505 .parse_dt = dw_mci_exynos_parse_dt, 506 .execute_tuning = dw_mci_exynos_execute_tuning, 507 .prepare_hs400_tuning = dw_mci_exynos_prepare_hs400_tuning, 508 }; 509 510 static const struct of_device_id dw_mci_exynos_match[] = { 511 { .compatible = "samsung,exynos4412-dw-mshc", 512 .data = &exynos_drv_data, }, 513 { .compatible = "samsung,exynos5250-dw-mshc", 514 .data = &exynos_drv_data, }, 515 { .compatible = "samsung,exynos5420-dw-mshc", 516 .data = &exynos_drv_data, }, 517 { .compatible = "samsung,exynos5420-dw-mshc-smu", 518 .data = &exynos_drv_data, }, 519 { .compatible = "samsung,exynos7-dw-mshc", 520 .data = &exynos_drv_data, }, 521 { .compatible = "samsung,exynos7-dw-mshc-smu", 522 .data = &exynos_drv_data, }, 523 {}, 524 }; 525 MODULE_DEVICE_TABLE(of, dw_mci_exynos_match); 526 527 static int dw_mci_exynos_probe(struct platform_device *pdev) 528 { 529 const struct dw_mci_drv_data *drv_data; 530 const struct of_device_id *match; 531 532 match = of_match_node(dw_mci_exynos_match, pdev->dev.of_node); 533 drv_data = match->data; 534 return dw_mci_pltfm_register(pdev, drv_data); 535 } 536 537 static const struct dev_pm_ops dw_mci_exynos_pmops = { 538 SET_SYSTEM_SLEEP_PM_OPS(dw_mci_exynos_suspend, dw_mci_exynos_resume) 539 .resume_noirq = dw_mci_exynos_resume_noirq, 540 .thaw_noirq = dw_mci_exynos_resume_noirq, 541 .restore_noirq = dw_mci_exynos_resume_noirq, 542 }; 543 544 static struct platform_driver dw_mci_exynos_pltfm_driver = { 545 .probe = dw_mci_exynos_probe, 546 .remove = dw_mci_pltfm_remove, 547 .driver = { 548 .name = "dwmmc_exynos", 549 .of_match_table = dw_mci_exynos_match, 550 .pm = &dw_mci_exynos_pmops, 551 }, 552 }; 553 554 module_platform_driver(dw_mci_exynos_pltfm_driver); 555 556 MODULE_DESCRIPTION("Samsung Specific DW-MSHC Driver Extension"); 557 MODULE_AUTHOR("Thomas Abraham <thomas.ab@samsung.com"); 558 MODULE_LICENSE("GPL v2"); 559 MODULE_ALIAS("platform:dwmmc-exynos"); 560