1 /* 2 * drivers/mmc/host/sdhci-msm.c - Qualcomm SDHCI Platform driver 3 * 4 * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved. 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 version 2 and 8 * only version 2 as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 */ 16 17 #include <linux/module.h> 18 #include <linux/of_device.h> 19 #include <linux/delay.h> 20 #include <linux/mmc/mmc.h> 21 #include <linux/slab.h> 22 23 #include "sdhci-pltfm.h" 24 25 #define CORE_HC_MODE 0x78 26 #define HC_MODE_EN 0x1 27 #define CORE_POWER 0x0 28 #define CORE_SW_RST BIT(7) 29 30 #define MAX_PHASES 16 31 #define CORE_DLL_LOCK BIT(7) 32 #define CORE_DLL_EN BIT(16) 33 #define CORE_CDR_EN BIT(17) 34 #define CORE_CK_OUT_EN BIT(18) 35 #define CORE_CDR_EXT_EN BIT(19) 36 #define CORE_DLL_PDN BIT(29) 37 #define CORE_DLL_RST BIT(30) 38 #define CORE_DLL_CONFIG 0x100 39 #define CORE_DLL_STATUS 0x108 40 41 #define CORE_VENDOR_SPEC 0x10c 42 #define CORE_CLK_PWRSAVE BIT(1) 43 44 #define CDR_SELEXT_SHIFT 20 45 #define CDR_SELEXT_MASK (0xf << CDR_SELEXT_SHIFT) 46 #define CMUX_SHIFT_PHASE_SHIFT 24 47 #define CMUX_SHIFT_PHASE_MASK (7 << CMUX_SHIFT_PHASE_SHIFT) 48 49 struct sdhci_msm_host { 50 struct platform_device *pdev; 51 void __iomem *core_mem; /* MSM SDCC mapped address */ 52 struct clk *clk; /* main SD/MMC bus clock */ 53 struct clk *pclk; /* SDHC peripheral bus clock */ 54 struct clk *bus_clk; /* SDHC bus voter clock */ 55 struct mmc_host *mmc; 56 struct sdhci_pltfm_data sdhci_msm_pdata; 57 }; 58 59 /* Platform specific tuning */ 60 static inline int msm_dll_poll_ck_out_en(struct sdhci_host *host, u8 poll) 61 { 62 u32 wait_cnt = 50; 63 u8 ck_out_en; 64 struct mmc_host *mmc = host->mmc; 65 66 /* Poll for CK_OUT_EN bit. max. poll time = 50us */ 67 ck_out_en = !!(readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) & 68 CORE_CK_OUT_EN); 69 70 while (ck_out_en != poll) { 71 if (--wait_cnt == 0) { 72 dev_err(mmc_dev(mmc), "%s: CK_OUT_EN bit is not %d\n", 73 mmc_hostname(mmc), poll); 74 return -ETIMEDOUT; 75 } 76 udelay(1); 77 78 ck_out_en = !!(readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) & 79 CORE_CK_OUT_EN); 80 } 81 82 return 0; 83 } 84 85 static int msm_config_cm_dll_phase(struct sdhci_host *host, u8 phase) 86 { 87 int rc; 88 static const u8 grey_coded_phase_table[] = { 89 0x0, 0x1, 0x3, 0x2, 0x6, 0x7, 0x5, 0x4, 90 0xc, 0xd, 0xf, 0xe, 0xa, 0xb, 0x9, 0x8 91 }; 92 unsigned long flags; 93 u32 config; 94 struct mmc_host *mmc = host->mmc; 95 96 spin_lock_irqsave(&host->lock, flags); 97 98 config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG); 99 config &= ~(CORE_CDR_EN | CORE_CK_OUT_EN); 100 config |= (CORE_CDR_EXT_EN | CORE_DLL_EN); 101 writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG); 102 103 /* Wait until CK_OUT_EN bit of DLL_CONFIG register becomes '0' */ 104 rc = msm_dll_poll_ck_out_en(host, 0); 105 if (rc) 106 goto err_out; 107 108 /* 109 * Write the selected DLL clock output phase (0 ... 15) 110 * to CDR_SELEXT bit field of DLL_CONFIG register. 111 */ 112 config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG); 113 config &= ~CDR_SELEXT_MASK; 114 config |= grey_coded_phase_table[phase] << CDR_SELEXT_SHIFT; 115 writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG); 116 117 /* Set CK_OUT_EN bit of DLL_CONFIG register to 1. */ 118 writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) 119 | CORE_CK_OUT_EN), host->ioaddr + CORE_DLL_CONFIG); 120 121 /* Wait until CK_OUT_EN bit of DLL_CONFIG register becomes '1' */ 122 rc = msm_dll_poll_ck_out_en(host, 1); 123 if (rc) 124 goto err_out; 125 126 config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG); 127 config |= CORE_CDR_EN; 128 config &= ~CORE_CDR_EXT_EN; 129 writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG); 130 goto out; 131 132 err_out: 133 dev_err(mmc_dev(mmc), "%s: Failed to set DLL phase: %d\n", 134 mmc_hostname(mmc), phase); 135 out: 136 spin_unlock_irqrestore(&host->lock, flags); 137 return rc; 138 } 139 140 /* 141 * Find out the greatest range of consecuitive selected 142 * DLL clock output phases that can be used as sampling 143 * setting for SD3.0 UHS-I card read operation (in SDR104 144 * timing mode) or for eMMC4.5 card read operation (in HS200 145 * timing mode). 146 * Select the 3/4 of the range and configure the DLL with the 147 * selected DLL clock output phase. 148 */ 149 150 static int msm_find_most_appropriate_phase(struct sdhci_host *host, 151 u8 *phase_table, u8 total_phases) 152 { 153 int ret; 154 u8 ranges[MAX_PHASES][MAX_PHASES] = { {0}, {0} }; 155 u8 phases_per_row[MAX_PHASES] = { 0 }; 156 int row_index = 0, col_index = 0, selected_row_index = 0, curr_max = 0; 157 int i, cnt, phase_0_raw_index = 0, phase_15_raw_index = 0; 158 bool phase_0_found = false, phase_15_found = false; 159 struct mmc_host *mmc = host->mmc; 160 161 if (!total_phases || (total_phases > MAX_PHASES)) { 162 dev_err(mmc_dev(mmc), "%s: Invalid argument: total_phases=%d\n", 163 mmc_hostname(mmc), total_phases); 164 return -EINVAL; 165 } 166 167 for (cnt = 0; cnt < total_phases; cnt++) { 168 ranges[row_index][col_index] = phase_table[cnt]; 169 phases_per_row[row_index] += 1; 170 col_index++; 171 172 if ((cnt + 1) == total_phases) { 173 continue; 174 /* check if next phase in phase_table is consecutive or not */ 175 } else if ((phase_table[cnt] + 1) != phase_table[cnt + 1]) { 176 row_index++; 177 col_index = 0; 178 } 179 } 180 181 if (row_index >= MAX_PHASES) 182 return -EINVAL; 183 184 /* Check if phase-0 is present in first valid window? */ 185 if (!ranges[0][0]) { 186 phase_0_found = true; 187 phase_0_raw_index = 0; 188 /* Check if cycle exist between 2 valid windows */ 189 for (cnt = 1; cnt <= row_index; cnt++) { 190 if (phases_per_row[cnt]) { 191 for (i = 0; i < phases_per_row[cnt]; i++) { 192 if (ranges[cnt][i] == 15) { 193 phase_15_found = true; 194 phase_15_raw_index = cnt; 195 break; 196 } 197 } 198 } 199 } 200 } 201 202 /* If 2 valid windows form cycle then merge them as single window */ 203 if (phase_0_found && phase_15_found) { 204 /* number of phases in raw where phase 0 is present */ 205 u8 phases_0 = phases_per_row[phase_0_raw_index]; 206 /* number of phases in raw where phase 15 is present */ 207 u8 phases_15 = phases_per_row[phase_15_raw_index]; 208 209 if (phases_0 + phases_15 >= MAX_PHASES) 210 /* 211 * If there are more than 1 phase windows then total 212 * number of phases in both the windows should not be 213 * more than or equal to MAX_PHASES. 214 */ 215 return -EINVAL; 216 217 /* Merge 2 cyclic windows */ 218 i = phases_15; 219 for (cnt = 0; cnt < phases_0; cnt++) { 220 ranges[phase_15_raw_index][i] = 221 ranges[phase_0_raw_index][cnt]; 222 if (++i >= MAX_PHASES) 223 break; 224 } 225 226 phases_per_row[phase_0_raw_index] = 0; 227 phases_per_row[phase_15_raw_index] = phases_15 + phases_0; 228 } 229 230 for (cnt = 0; cnt <= row_index; cnt++) { 231 if (phases_per_row[cnt] > curr_max) { 232 curr_max = phases_per_row[cnt]; 233 selected_row_index = cnt; 234 } 235 } 236 237 i = (curr_max * 3) / 4; 238 if (i) 239 i--; 240 241 ret = ranges[selected_row_index][i]; 242 243 if (ret >= MAX_PHASES) { 244 ret = -EINVAL; 245 dev_err(mmc_dev(mmc), "%s: Invalid phase selected=%d\n", 246 mmc_hostname(mmc), ret); 247 } 248 249 return ret; 250 } 251 252 static inline void msm_cm_dll_set_freq(struct sdhci_host *host) 253 { 254 u32 mclk_freq = 0, config; 255 256 /* Program the MCLK value to MCLK_FREQ bit field */ 257 if (host->clock <= 112000000) 258 mclk_freq = 0; 259 else if (host->clock <= 125000000) 260 mclk_freq = 1; 261 else if (host->clock <= 137000000) 262 mclk_freq = 2; 263 else if (host->clock <= 150000000) 264 mclk_freq = 3; 265 else if (host->clock <= 162000000) 266 mclk_freq = 4; 267 else if (host->clock <= 175000000) 268 mclk_freq = 5; 269 else if (host->clock <= 187000000) 270 mclk_freq = 6; 271 else if (host->clock <= 200000000) 272 mclk_freq = 7; 273 274 config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG); 275 config &= ~CMUX_SHIFT_PHASE_MASK; 276 config |= mclk_freq << CMUX_SHIFT_PHASE_SHIFT; 277 writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG); 278 } 279 280 /* Initialize the DLL (Programmable Delay Line) */ 281 static int msm_init_cm_dll(struct sdhci_host *host) 282 { 283 struct mmc_host *mmc = host->mmc; 284 int wait_cnt = 50; 285 unsigned long flags; 286 287 spin_lock_irqsave(&host->lock, flags); 288 289 /* 290 * Make sure that clock is always enabled when DLL 291 * tuning is in progress. Keeping PWRSAVE ON may 292 * turn off the clock. 293 */ 294 writel_relaxed((readl_relaxed(host->ioaddr + CORE_VENDOR_SPEC) 295 & ~CORE_CLK_PWRSAVE), host->ioaddr + CORE_VENDOR_SPEC); 296 297 /* Write 1 to DLL_RST bit of DLL_CONFIG register */ 298 writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) 299 | CORE_DLL_RST), host->ioaddr + CORE_DLL_CONFIG); 300 301 /* Write 1 to DLL_PDN bit of DLL_CONFIG register */ 302 writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) 303 | CORE_DLL_PDN), host->ioaddr + CORE_DLL_CONFIG); 304 msm_cm_dll_set_freq(host); 305 306 /* Write 0 to DLL_RST bit of DLL_CONFIG register */ 307 writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) 308 & ~CORE_DLL_RST), host->ioaddr + CORE_DLL_CONFIG); 309 310 /* Write 0 to DLL_PDN bit of DLL_CONFIG register */ 311 writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) 312 & ~CORE_DLL_PDN), host->ioaddr + CORE_DLL_CONFIG); 313 314 /* Set DLL_EN bit to 1. */ 315 writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) 316 | CORE_DLL_EN), host->ioaddr + CORE_DLL_CONFIG); 317 318 /* Set CK_OUT_EN bit to 1. */ 319 writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) 320 | CORE_CK_OUT_EN), host->ioaddr + CORE_DLL_CONFIG); 321 322 /* Wait until DLL_LOCK bit of DLL_STATUS register becomes '1' */ 323 while (!(readl_relaxed(host->ioaddr + CORE_DLL_STATUS) & 324 CORE_DLL_LOCK)) { 325 /* max. wait for 50us sec for LOCK bit to be set */ 326 if (--wait_cnt == 0) { 327 dev_err(mmc_dev(mmc), "%s: DLL failed to LOCK\n", 328 mmc_hostname(mmc)); 329 spin_unlock_irqrestore(&host->lock, flags); 330 return -ETIMEDOUT; 331 } 332 udelay(1); 333 } 334 335 spin_unlock_irqrestore(&host->lock, flags); 336 return 0; 337 } 338 339 static int sdhci_msm_execute_tuning(struct sdhci_host *host, u32 opcode) 340 { 341 int tuning_seq_cnt = 3; 342 u8 phase, tuned_phases[16], tuned_phase_cnt = 0; 343 int rc; 344 struct mmc_host *mmc = host->mmc; 345 struct mmc_ios ios = host->mmc->ios; 346 347 /* 348 * Tuning is required for SDR104, HS200 and HS400 cards and 349 * if clock frequency is greater than 100MHz in these modes. 350 */ 351 if (host->clock <= 100 * 1000 * 1000 || 352 !((ios.timing == MMC_TIMING_MMC_HS200) || 353 (ios.timing == MMC_TIMING_UHS_SDR104))) 354 return 0; 355 356 retry: 357 /* First of all reset the tuning block */ 358 rc = msm_init_cm_dll(host); 359 if (rc) 360 return rc; 361 362 phase = 0; 363 do { 364 /* Set the phase in delay line hw block */ 365 rc = msm_config_cm_dll_phase(host, phase); 366 if (rc) 367 return rc; 368 369 rc = mmc_send_tuning(mmc); 370 if (!rc) { 371 /* Tuning is successful at this tuning point */ 372 tuned_phases[tuned_phase_cnt++] = phase; 373 dev_dbg(mmc_dev(mmc), "%s: Found good phase = %d\n", 374 mmc_hostname(mmc), phase); 375 } 376 } while (++phase < ARRAY_SIZE(tuned_phases)); 377 378 if (tuned_phase_cnt) { 379 rc = msm_find_most_appropriate_phase(host, tuned_phases, 380 tuned_phase_cnt); 381 if (rc < 0) 382 return rc; 383 else 384 phase = rc; 385 386 /* 387 * Finally set the selected phase in delay 388 * line hw block. 389 */ 390 rc = msm_config_cm_dll_phase(host, phase); 391 if (rc) 392 return rc; 393 dev_dbg(mmc_dev(mmc), "%s: Setting the tuning phase to %d\n", 394 mmc_hostname(mmc), phase); 395 } else { 396 if (--tuning_seq_cnt) 397 goto retry; 398 /* Tuning failed */ 399 dev_dbg(mmc_dev(mmc), "%s: No tuning point found\n", 400 mmc_hostname(mmc)); 401 rc = -EIO; 402 } 403 404 return rc; 405 } 406 407 static const struct of_device_id sdhci_msm_dt_match[] = { 408 { .compatible = "qcom,sdhci-msm-v4" }, 409 {}, 410 }; 411 412 MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match); 413 414 static struct sdhci_ops sdhci_msm_ops = { 415 .platform_execute_tuning = sdhci_msm_execute_tuning, 416 .reset = sdhci_reset, 417 .set_clock = sdhci_set_clock, 418 .set_bus_width = sdhci_set_bus_width, 419 .set_uhs_signaling = sdhci_set_uhs_signaling, 420 }; 421 422 static int sdhci_msm_probe(struct platform_device *pdev) 423 { 424 struct sdhci_host *host; 425 struct sdhci_pltfm_host *pltfm_host; 426 struct sdhci_msm_host *msm_host; 427 struct resource *core_memres; 428 int ret; 429 u16 host_version; 430 431 msm_host = devm_kzalloc(&pdev->dev, sizeof(*msm_host), GFP_KERNEL); 432 if (!msm_host) 433 return -ENOMEM; 434 435 msm_host->sdhci_msm_pdata.ops = &sdhci_msm_ops; 436 host = sdhci_pltfm_init(pdev, &msm_host->sdhci_msm_pdata, 0); 437 if (IS_ERR(host)) 438 return PTR_ERR(host); 439 440 pltfm_host = sdhci_priv(host); 441 pltfm_host->priv = msm_host; 442 msm_host->mmc = host->mmc; 443 msm_host->pdev = pdev; 444 445 ret = mmc_of_parse(host->mmc); 446 if (ret) 447 goto pltfm_free; 448 449 sdhci_get_of_property(pdev); 450 451 /* Setup SDCC bus voter clock. */ 452 msm_host->bus_clk = devm_clk_get(&pdev->dev, "bus"); 453 if (!IS_ERR(msm_host->bus_clk)) { 454 /* Vote for max. clk rate for max. performance */ 455 ret = clk_set_rate(msm_host->bus_clk, INT_MAX); 456 if (ret) 457 goto pltfm_free; 458 ret = clk_prepare_enable(msm_host->bus_clk); 459 if (ret) 460 goto pltfm_free; 461 } 462 463 /* Setup main peripheral bus clock */ 464 msm_host->pclk = devm_clk_get(&pdev->dev, "iface"); 465 if (IS_ERR(msm_host->pclk)) { 466 ret = PTR_ERR(msm_host->pclk); 467 dev_err(&pdev->dev, "Perpheral clk setup failed (%d)\n", ret); 468 goto bus_clk_disable; 469 } 470 471 ret = clk_prepare_enable(msm_host->pclk); 472 if (ret) 473 goto bus_clk_disable; 474 475 /* Setup SDC MMC clock */ 476 msm_host->clk = devm_clk_get(&pdev->dev, "core"); 477 if (IS_ERR(msm_host->clk)) { 478 ret = PTR_ERR(msm_host->clk); 479 dev_err(&pdev->dev, "SDC MMC clk setup failed (%d)\n", ret); 480 goto pclk_disable; 481 } 482 483 ret = clk_prepare_enable(msm_host->clk); 484 if (ret) 485 goto pclk_disable; 486 487 core_memres = platform_get_resource(pdev, IORESOURCE_MEM, 1); 488 msm_host->core_mem = devm_ioremap_resource(&pdev->dev, core_memres); 489 490 if (IS_ERR(msm_host->core_mem)) { 491 dev_err(&pdev->dev, "Failed to remap registers\n"); 492 ret = PTR_ERR(msm_host->core_mem); 493 goto clk_disable; 494 } 495 496 /* Reset the core and Enable SDHC mode */ 497 writel_relaxed(readl_relaxed(msm_host->core_mem + CORE_POWER) | 498 CORE_SW_RST, msm_host->core_mem + CORE_POWER); 499 500 /* SW reset can take upto 10HCLK + 15MCLK cycles. (min 40us) */ 501 usleep_range(1000, 5000); 502 if (readl(msm_host->core_mem + CORE_POWER) & CORE_SW_RST) { 503 dev_err(&pdev->dev, "Stuck in reset\n"); 504 ret = -ETIMEDOUT; 505 goto clk_disable; 506 } 507 508 /* Set HC_MODE_EN bit in HC_MODE register */ 509 writel_relaxed(HC_MODE_EN, (msm_host->core_mem + CORE_HC_MODE)); 510 511 host->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION; 512 host->quirks |= SDHCI_QUIRK_SINGLE_POWER_WRITE; 513 514 host_version = readw_relaxed((host->ioaddr + SDHCI_HOST_VERSION)); 515 dev_dbg(&pdev->dev, "Host Version: 0x%x Vendor Version 0x%x\n", 516 host_version, ((host_version & SDHCI_VENDOR_VER_MASK) >> 517 SDHCI_VENDOR_VER_SHIFT)); 518 519 ret = sdhci_add_host(host); 520 if (ret) 521 goto clk_disable; 522 523 return 0; 524 525 clk_disable: 526 clk_disable_unprepare(msm_host->clk); 527 pclk_disable: 528 clk_disable_unprepare(msm_host->pclk); 529 bus_clk_disable: 530 if (!IS_ERR(msm_host->bus_clk)) 531 clk_disable_unprepare(msm_host->bus_clk); 532 pltfm_free: 533 sdhci_pltfm_free(pdev); 534 return ret; 535 } 536 537 static int sdhci_msm_remove(struct platform_device *pdev) 538 { 539 struct sdhci_host *host = platform_get_drvdata(pdev); 540 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); 541 struct sdhci_msm_host *msm_host = pltfm_host->priv; 542 int dead = (readl_relaxed(host->ioaddr + SDHCI_INT_STATUS) == 543 0xffffffff); 544 545 sdhci_remove_host(host, dead); 546 sdhci_pltfm_free(pdev); 547 clk_disable_unprepare(msm_host->clk); 548 clk_disable_unprepare(msm_host->pclk); 549 if (!IS_ERR(msm_host->bus_clk)) 550 clk_disable_unprepare(msm_host->bus_clk); 551 return 0; 552 } 553 554 static struct platform_driver sdhci_msm_driver = { 555 .probe = sdhci_msm_probe, 556 .remove = sdhci_msm_remove, 557 .driver = { 558 .name = "sdhci_msm", 559 .of_match_table = sdhci_msm_dt_match, 560 }, 561 }; 562 563 module_platform_driver(sdhci_msm_driver); 564 565 MODULE_DESCRIPTION("Qualcomm Secure Digital Host Controller Interface driver"); 566 MODULE_LICENSE("GPL v2"); 567