1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) STMicroelectronics 2018 - All Rights Reserved 4 * Author: Ludovic.barre@st.com for STMicroelectronics. 5 */ 6 #include <linux/bitfield.h> 7 #include <linux/delay.h> 8 #include <linux/dma-mapping.h> 9 #include <linux/iopoll.h> 10 #include <linux/mmc/host.h> 11 #include <linux/mmc/card.h> 12 #include <linux/of_address.h> 13 #include <linux/reset.h> 14 #include <linux/scatterlist.h> 15 #include "mmci.h" 16 17 #define SDMMC_LLI_BUF_LEN PAGE_SIZE 18 #define SDMMC_IDMA_BURST BIT(MMCI_STM32_IDMABNDT_SHIFT) 19 20 #define DLYB_CR 0x0 21 #define DLYB_CR_DEN BIT(0) 22 #define DLYB_CR_SEN BIT(1) 23 24 #define DLYB_CFGR 0x4 25 #define DLYB_CFGR_SEL_MASK GENMASK(3, 0) 26 #define DLYB_CFGR_UNIT_MASK GENMASK(14, 8) 27 #define DLYB_CFGR_LNG_MASK GENMASK(27, 16) 28 #define DLYB_CFGR_LNGF BIT(31) 29 30 #define DLYB_NB_DELAY 11 31 #define DLYB_CFGR_SEL_MAX (DLYB_NB_DELAY + 1) 32 #define DLYB_CFGR_UNIT_MAX 127 33 34 #define DLYB_LNG_TIMEOUT_US 1000 35 #define SDMMC_VSWEND_TIMEOUT_US 10000 36 37 struct sdmmc_lli_desc { 38 u32 idmalar; 39 u32 idmabase; 40 u32 idmasize; 41 }; 42 43 struct sdmmc_idma { 44 dma_addr_t sg_dma; 45 void *sg_cpu; 46 }; 47 48 struct sdmmc_dlyb { 49 void __iomem *base; 50 u32 unit; 51 u32 max; 52 }; 53 54 static int sdmmc_idma_validate_data(struct mmci_host *host, 55 struct mmc_data *data) 56 { 57 struct scatterlist *sg; 58 int i; 59 60 /* 61 * idma has constraints on idmabase & idmasize for each element 62 * excepted the last element which has no constraint on idmasize 63 */ 64 for_each_sg(data->sg, sg, data->sg_len - 1, i) { 65 if (!IS_ALIGNED(sg->offset, sizeof(u32)) || 66 !IS_ALIGNED(sg->length, SDMMC_IDMA_BURST)) { 67 dev_err(mmc_dev(host->mmc), 68 "unaligned scatterlist: ofst:%x length:%d\n", 69 data->sg->offset, data->sg->length); 70 return -EINVAL; 71 } 72 } 73 74 if (!IS_ALIGNED(sg->offset, sizeof(u32))) { 75 dev_err(mmc_dev(host->mmc), 76 "unaligned last scatterlist: ofst:%x length:%d\n", 77 data->sg->offset, data->sg->length); 78 return -EINVAL; 79 } 80 81 return 0; 82 } 83 84 static int _sdmmc_idma_prep_data(struct mmci_host *host, 85 struct mmc_data *data) 86 { 87 int n_elem; 88 89 n_elem = dma_map_sg(mmc_dev(host->mmc), 90 data->sg, 91 data->sg_len, 92 mmc_get_dma_dir(data)); 93 94 if (!n_elem) { 95 dev_err(mmc_dev(host->mmc), "dma_map_sg failed\n"); 96 return -EINVAL; 97 } 98 99 return 0; 100 } 101 102 static int sdmmc_idma_prep_data(struct mmci_host *host, 103 struct mmc_data *data, bool next) 104 { 105 /* Check if job is already prepared. */ 106 if (!next && data->host_cookie == host->next_cookie) 107 return 0; 108 109 return _sdmmc_idma_prep_data(host, data); 110 } 111 112 static void sdmmc_idma_unprep_data(struct mmci_host *host, 113 struct mmc_data *data, int err) 114 { 115 dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len, 116 mmc_get_dma_dir(data)); 117 } 118 119 static int sdmmc_idma_setup(struct mmci_host *host) 120 { 121 struct sdmmc_idma *idma; 122 struct device *dev = mmc_dev(host->mmc); 123 124 idma = devm_kzalloc(dev, sizeof(*idma), GFP_KERNEL); 125 if (!idma) 126 return -ENOMEM; 127 128 host->dma_priv = idma; 129 130 if (host->variant->dma_lli) { 131 idma->sg_cpu = dmam_alloc_coherent(dev, SDMMC_LLI_BUF_LEN, 132 &idma->sg_dma, GFP_KERNEL); 133 if (!idma->sg_cpu) { 134 dev_err(dev, "Failed to alloc IDMA descriptor\n"); 135 return -ENOMEM; 136 } 137 host->mmc->max_segs = SDMMC_LLI_BUF_LEN / 138 sizeof(struct sdmmc_lli_desc); 139 host->mmc->max_seg_size = host->variant->stm32_idmabsize_mask; 140 } else { 141 host->mmc->max_segs = 1; 142 host->mmc->max_seg_size = host->mmc->max_req_size; 143 } 144 145 return dma_set_max_seg_size(dev, host->mmc->max_seg_size); 146 } 147 148 static int sdmmc_idma_start(struct mmci_host *host, unsigned int *datactrl) 149 150 { 151 struct sdmmc_idma *idma = host->dma_priv; 152 struct sdmmc_lli_desc *desc = (struct sdmmc_lli_desc *)idma->sg_cpu; 153 struct mmc_data *data = host->data; 154 struct scatterlist *sg; 155 int i; 156 157 if (!host->variant->dma_lli || data->sg_len == 1) { 158 writel_relaxed(sg_dma_address(data->sg), 159 host->base + MMCI_STM32_IDMABASE0R); 160 writel_relaxed(MMCI_STM32_IDMAEN, 161 host->base + MMCI_STM32_IDMACTRLR); 162 return 0; 163 } 164 165 for_each_sg(data->sg, sg, data->sg_len, i) { 166 desc[i].idmalar = (i + 1) * sizeof(struct sdmmc_lli_desc); 167 desc[i].idmalar |= MMCI_STM32_ULA | MMCI_STM32_ULS 168 | MMCI_STM32_ABR; 169 desc[i].idmabase = sg_dma_address(sg); 170 desc[i].idmasize = sg_dma_len(sg); 171 } 172 173 /* notice the end of link list */ 174 desc[data->sg_len - 1].idmalar &= ~MMCI_STM32_ULA; 175 176 dma_wmb(); 177 writel_relaxed(idma->sg_dma, host->base + MMCI_STM32_IDMABAR); 178 writel_relaxed(desc[0].idmalar, host->base + MMCI_STM32_IDMALAR); 179 writel_relaxed(desc[0].idmabase, host->base + MMCI_STM32_IDMABASE0R); 180 writel_relaxed(desc[0].idmasize, host->base + MMCI_STM32_IDMABSIZER); 181 writel_relaxed(MMCI_STM32_IDMAEN | MMCI_STM32_IDMALLIEN, 182 host->base + MMCI_STM32_IDMACTRLR); 183 184 return 0; 185 } 186 187 static void sdmmc_idma_finalize(struct mmci_host *host, struct mmc_data *data) 188 { 189 writel_relaxed(0, host->base + MMCI_STM32_IDMACTRLR); 190 191 if (!data->host_cookie) 192 sdmmc_idma_unprep_data(host, data, 0); 193 } 194 195 static void mmci_sdmmc_set_clkreg(struct mmci_host *host, unsigned int desired) 196 { 197 unsigned int clk = 0, ddr = 0; 198 199 if (host->mmc->ios.timing == MMC_TIMING_MMC_DDR52 || 200 host->mmc->ios.timing == MMC_TIMING_UHS_DDR50) 201 ddr = MCI_STM32_CLK_DDR; 202 203 /* 204 * cclk = mclk / (2 * clkdiv) 205 * clkdiv 0 => bypass 206 * in ddr mode bypass is not possible 207 */ 208 if (desired) { 209 if (desired >= host->mclk && !ddr) { 210 host->cclk = host->mclk; 211 } else { 212 clk = DIV_ROUND_UP(host->mclk, 2 * desired); 213 if (clk > MCI_STM32_CLK_CLKDIV_MSK) 214 clk = MCI_STM32_CLK_CLKDIV_MSK; 215 host->cclk = host->mclk / (2 * clk); 216 } 217 } else { 218 /* 219 * while power-on phase the clock can't be define to 0, 220 * Only power-off and power-cyc deactivate the clock. 221 * if desired clock is 0, set max divider 222 */ 223 clk = MCI_STM32_CLK_CLKDIV_MSK; 224 host->cclk = host->mclk / (2 * clk); 225 } 226 227 /* Set actual clock for debug */ 228 if (host->mmc->ios.power_mode == MMC_POWER_ON) 229 host->mmc->actual_clock = host->cclk; 230 else 231 host->mmc->actual_clock = 0; 232 233 if (host->mmc->ios.bus_width == MMC_BUS_WIDTH_4) 234 clk |= MCI_STM32_CLK_WIDEBUS_4; 235 if (host->mmc->ios.bus_width == MMC_BUS_WIDTH_8) 236 clk |= MCI_STM32_CLK_WIDEBUS_8; 237 238 clk |= MCI_STM32_CLK_HWFCEN; 239 clk |= host->clk_reg_add; 240 clk |= ddr; 241 242 /* 243 * SDMMC_FBCK is selected when an external Delay Block is needed 244 * with SDR104 or HS200. 245 */ 246 if (host->mmc->ios.timing >= MMC_TIMING_UHS_SDR50) { 247 clk |= MCI_STM32_CLK_BUSSPEED; 248 if (host->mmc->ios.timing == MMC_TIMING_UHS_SDR104 || 249 host->mmc->ios.timing == MMC_TIMING_MMC_HS200) { 250 clk &= ~MCI_STM32_CLK_SEL_MSK; 251 clk |= MCI_STM32_CLK_SELFBCK; 252 } 253 } 254 255 mmci_write_clkreg(host, clk); 256 } 257 258 static void sdmmc_dlyb_input_ck(struct sdmmc_dlyb *dlyb) 259 { 260 if (!dlyb || !dlyb->base) 261 return; 262 263 /* Output clock = Input clock */ 264 writel_relaxed(0, dlyb->base + DLYB_CR); 265 } 266 267 static void mmci_sdmmc_set_pwrreg(struct mmci_host *host, unsigned int pwr) 268 { 269 struct mmc_ios ios = host->mmc->ios; 270 struct sdmmc_dlyb *dlyb = host->variant_priv; 271 272 /* adds OF options */ 273 pwr = host->pwr_reg_add; 274 275 sdmmc_dlyb_input_ck(dlyb); 276 277 if (ios.power_mode == MMC_POWER_OFF) { 278 /* Only a reset could power-off sdmmc */ 279 reset_control_assert(host->rst); 280 udelay(2); 281 reset_control_deassert(host->rst); 282 283 /* 284 * Set the SDMMC in Power-cycle state. 285 * This will make that the SDMMC_D[7:0], SDMMC_CMD and SDMMC_CK 286 * are driven low, to prevent the Card from being supplied 287 * through the signal lines. 288 */ 289 mmci_write_pwrreg(host, MCI_STM32_PWR_CYC | pwr); 290 } else if (ios.power_mode == MMC_POWER_ON) { 291 /* 292 * After power-off (reset): the irq mask defined in probe 293 * functionis lost 294 * ault irq mask (probe) must be activated 295 */ 296 writel(MCI_IRQENABLE | host->variant->start_err, 297 host->base + MMCIMASK0); 298 299 /* preserves voltage switch bits */ 300 pwr |= host->pwr_reg & (MCI_STM32_VSWITCHEN | 301 MCI_STM32_VSWITCH); 302 303 /* 304 * After a power-cycle state, we must set the SDMMC in 305 * Power-off. The SDMMC_D[7:0], SDMMC_CMD and SDMMC_CK are 306 * driven high. Then we can set the SDMMC to Power-on state 307 */ 308 mmci_write_pwrreg(host, MCI_PWR_OFF | pwr); 309 mdelay(1); 310 mmci_write_pwrreg(host, MCI_PWR_ON | pwr); 311 } 312 } 313 314 static u32 sdmmc_get_dctrl_cfg(struct mmci_host *host) 315 { 316 u32 datactrl; 317 318 datactrl = mmci_dctrl_blksz(host); 319 320 if (host->mmc->card && mmc_card_sdio(host->mmc->card) && 321 host->data->blocks == 1) 322 datactrl |= MCI_DPSM_STM32_MODE_SDIO; 323 else if (host->data->stop && !host->mrq->sbc) 324 datactrl |= MCI_DPSM_STM32_MODE_BLOCK_STOP; 325 else 326 datactrl |= MCI_DPSM_STM32_MODE_BLOCK; 327 328 return datactrl; 329 } 330 331 static bool sdmmc_busy_complete(struct mmci_host *host, u32 status, u32 err_msk) 332 { 333 void __iomem *base = host->base; 334 u32 busy_d0, busy_d0end, mask, sdmmc_status; 335 336 mask = readl_relaxed(base + MMCIMASK0); 337 sdmmc_status = readl_relaxed(base + MMCISTATUS); 338 busy_d0end = sdmmc_status & MCI_STM32_BUSYD0END; 339 busy_d0 = sdmmc_status & MCI_STM32_BUSYD0; 340 341 /* complete if there is an error or busy_d0end */ 342 if ((status & err_msk) || busy_d0end) 343 goto complete; 344 345 /* 346 * On response the busy signaling is reflected in the BUSYD0 flag. 347 * if busy_d0 is in-progress we must activate busyd0end interrupt 348 * to wait this completion. Else this request has no busy step. 349 */ 350 if (busy_d0) { 351 if (!host->busy_status) { 352 writel_relaxed(mask | host->variant->busy_detect_mask, 353 base + MMCIMASK0); 354 host->busy_status = status & 355 (MCI_CMDSENT | MCI_CMDRESPEND); 356 } 357 return false; 358 } 359 360 complete: 361 if (host->busy_status) { 362 writel_relaxed(mask & ~host->variant->busy_detect_mask, 363 base + MMCIMASK0); 364 host->busy_status = 0; 365 } 366 367 writel_relaxed(host->variant->busy_detect_mask, base + MMCICLEAR); 368 369 return true; 370 } 371 372 static void sdmmc_dlyb_set_cfgr(struct sdmmc_dlyb *dlyb, 373 int unit, int phase, bool sampler) 374 { 375 u32 cfgr; 376 377 writel_relaxed(DLYB_CR_SEN | DLYB_CR_DEN, dlyb->base + DLYB_CR); 378 379 cfgr = FIELD_PREP(DLYB_CFGR_UNIT_MASK, unit) | 380 FIELD_PREP(DLYB_CFGR_SEL_MASK, phase); 381 writel_relaxed(cfgr, dlyb->base + DLYB_CFGR); 382 383 if (!sampler) 384 writel_relaxed(DLYB_CR_DEN, dlyb->base + DLYB_CR); 385 } 386 387 static int sdmmc_dlyb_lng_tuning(struct mmci_host *host) 388 { 389 struct sdmmc_dlyb *dlyb = host->variant_priv; 390 u32 cfgr; 391 int i, lng, ret; 392 393 for (i = 0; i <= DLYB_CFGR_UNIT_MAX; i++) { 394 sdmmc_dlyb_set_cfgr(dlyb, i, DLYB_CFGR_SEL_MAX, true); 395 396 ret = readl_relaxed_poll_timeout(dlyb->base + DLYB_CFGR, cfgr, 397 (cfgr & DLYB_CFGR_LNGF), 398 1, DLYB_LNG_TIMEOUT_US); 399 if (ret) { 400 dev_warn(mmc_dev(host->mmc), 401 "delay line cfg timeout unit:%d cfgr:%d\n", 402 i, cfgr); 403 continue; 404 } 405 406 lng = FIELD_GET(DLYB_CFGR_LNG_MASK, cfgr); 407 if (lng < BIT(DLYB_NB_DELAY) && lng > 0) 408 break; 409 } 410 411 if (i > DLYB_CFGR_UNIT_MAX) 412 return -EINVAL; 413 414 dlyb->unit = i; 415 dlyb->max = __fls(lng); 416 417 return 0; 418 } 419 420 static int sdmmc_dlyb_phase_tuning(struct mmci_host *host, u32 opcode) 421 { 422 struct sdmmc_dlyb *dlyb = host->variant_priv; 423 int cur_len = 0, max_len = 0, end_of_len = 0; 424 int phase; 425 426 for (phase = 0; phase <= dlyb->max; phase++) { 427 sdmmc_dlyb_set_cfgr(dlyb, dlyb->unit, phase, false); 428 429 if (mmc_send_tuning(host->mmc, opcode, NULL)) { 430 cur_len = 0; 431 } else { 432 cur_len++; 433 if (cur_len > max_len) { 434 max_len = cur_len; 435 end_of_len = phase; 436 } 437 } 438 } 439 440 if (!max_len) { 441 dev_err(mmc_dev(host->mmc), "no tuning point found\n"); 442 return -EINVAL; 443 } 444 445 writel_relaxed(0, dlyb->base + DLYB_CR); 446 447 phase = end_of_len - max_len / 2; 448 sdmmc_dlyb_set_cfgr(dlyb, dlyb->unit, phase, false); 449 450 dev_dbg(mmc_dev(host->mmc), "unit:%d max_dly:%d phase:%d\n", 451 dlyb->unit, dlyb->max, phase); 452 453 return 0; 454 } 455 456 static int sdmmc_execute_tuning(struct mmc_host *mmc, u32 opcode) 457 { 458 struct mmci_host *host = mmc_priv(mmc); 459 struct sdmmc_dlyb *dlyb = host->variant_priv; 460 461 if (!dlyb || !dlyb->base) 462 return -EINVAL; 463 464 if (sdmmc_dlyb_lng_tuning(host)) 465 return -EINVAL; 466 467 return sdmmc_dlyb_phase_tuning(host, opcode); 468 } 469 470 static void sdmmc_pre_sig_volt_vswitch(struct mmci_host *host) 471 { 472 /* clear the voltage switch completion flag */ 473 writel_relaxed(MCI_STM32_VSWENDC, host->base + MMCICLEAR); 474 /* enable Voltage switch procedure */ 475 mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCHEN); 476 } 477 478 static int sdmmc_post_sig_volt_switch(struct mmci_host *host, 479 struct mmc_ios *ios) 480 { 481 unsigned long flags; 482 u32 status; 483 int ret = 0; 484 485 spin_lock_irqsave(&host->lock, flags); 486 if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180 && 487 host->pwr_reg & MCI_STM32_VSWITCHEN) { 488 mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCH); 489 spin_unlock_irqrestore(&host->lock, flags); 490 491 /* wait voltage switch completion while 10ms */ 492 ret = readl_relaxed_poll_timeout(host->base + MMCISTATUS, 493 status, 494 (status & MCI_STM32_VSWEND), 495 10, SDMMC_VSWEND_TIMEOUT_US); 496 497 writel_relaxed(MCI_STM32_VSWENDC | MCI_STM32_CKSTOPC, 498 host->base + MMCICLEAR); 499 spin_lock_irqsave(&host->lock, flags); 500 mmci_write_pwrreg(host, host->pwr_reg & 501 ~(MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH)); 502 } 503 spin_unlock_irqrestore(&host->lock, flags); 504 505 return ret; 506 } 507 508 static struct mmci_host_ops sdmmc_variant_ops = { 509 .validate_data = sdmmc_idma_validate_data, 510 .prep_data = sdmmc_idma_prep_data, 511 .unprep_data = sdmmc_idma_unprep_data, 512 .get_datactrl_cfg = sdmmc_get_dctrl_cfg, 513 .dma_setup = sdmmc_idma_setup, 514 .dma_start = sdmmc_idma_start, 515 .dma_finalize = sdmmc_idma_finalize, 516 .set_clkreg = mmci_sdmmc_set_clkreg, 517 .set_pwrreg = mmci_sdmmc_set_pwrreg, 518 .busy_complete = sdmmc_busy_complete, 519 .pre_sig_volt_switch = sdmmc_pre_sig_volt_vswitch, 520 .post_sig_volt_switch = sdmmc_post_sig_volt_switch, 521 }; 522 523 void sdmmc_variant_init(struct mmci_host *host) 524 { 525 struct device_node *np = host->mmc->parent->of_node; 526 void __iomem *base_dlyb; 527 struct sdmmc_dlyb *dlyb; 528 529 host->ops = &sdmmc_variant_ops; 530 host->pwr_reg = readl_relaxed(host->base + MMCIPOWER); 531 532 base_dlyb = devm_of_iomap(mmc_dev(host->mmc), np, 1, NULL); 533 if (IS_ERR(base_dlyb)) 534 return; 535 536 dlyb = devm_kzalloc(mmc_dev(host->mmc), sizeof(*dlyb), GFP_KERNEL); 537 if (!dlyb) 538 return; 539 540 dlyb->base = base_dlyb; 541 host->variant_priv = dlyb; 542 host->mmc_ops->execute_tuning = sdmmc_execute_tuning; 543 } 544