1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * PCIe host controller driver for Freescale i.MX6 SoCs 4 * 5 * Copyright (C) 2013 Kosagi 6 * https://www.kosagi.com 7 * 8 * Author: Sean Cross <xobs@kosagi.com> 9 */ 10 11 #include <linux/bitfield.h> 12 #include <linux/clk.h> 13 #include <linux/delay.h> 14 #include <linux/gpio.h> 15 #include <linux/kernel.h> 16 #include <linux/mfd/syscon.h> 17 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h> 18 #include <linux/mfd/syscon/imx7-iomuxc-gpr.h> 19 #include <linux/module.h> 20 #include <linux/of_gpio.h> 21 #include <linux/of_device.h> 22 #include <linux/of_address.h> 23 #include <linux/pci.h> 24 #include <linux/platform_device.h> 25 #include <linux/regmap.h> 26 #include <linux/regulator/consumer.h> 27 #include <linux/resource.h> 28 #include <linux/signal.h> 29 #include <linux/types.h> 30 #include <linux/interrupt.h> 31 #include <linux/reset.h> 32 #include <linux/pm_domain.h> 33 #include <linux/pm_runtime.h> 34 35 #include "pcie-designware.h" 36 37 #define IMX8MQ_GPR_PCIE_REF_USE_PAD BIT(9) 38 #define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN BIT(10) 39 #define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE BIT(11) 40 #define IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE GENMASK(11, 8) 41 #define IMX8MQ_PCIE2_BASE_ADDR 0x33c00000 42 43 #define to_imx6_pcie(x) dev_get_drvdata((x)->dev) 44 45 enum imx6_pcie_variants { 46 IMX6Q, 47 IMX6SX, 48 IMX6QP, 49 IMX7D, 50 IMX8MQ, 51 }; 52 53 #define IMX6_PCIE_FLAG_IMX6_PHY BIT(0) 54 #define IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE BIT(1) 55 #define IMX6_PCIE_FLAG_SUPPORTS_SUSPEND BIT(2) 56 57 struct imx6_pcie_drvdata { 58 enum imx6_pcie_variants variant; 59 u32 flags; 60 int dbi_length; 61 }; 62 63 struct imx6_pcie { 64 struct dw_pcie *pci; 65 int reset_gpio; 66 bool gpio_active_high; 67 struct clk *pcie_bus; 68 struct clk *pcie_phy; 69 struct clk *pcie_inbound_axi; 70 struct clk *pcie; 71 struct clk *pcie_aux; 72 struct regmap *iomuxc_gpr; 73 u32 controller_id; 74 struct reset_control *pciephy_reset; 75 struct reset_control *apps_reset; 76 struct reset_control *turnoff_reset; 77 u32 tx_deemph_gen1; 78 u32 tx_deemph_gen2_3p5db; 79 u32 tx_deemph_gen2_6db; 80 u32 tx_swing_full; 81 u32 tx_swing_low; 82 struct regulator *vpcie; 83 void __iomem *phy_base; 84 85 /* power domain for pcie */ 86 struct device *pd_pcie; 87 /* power domain for pcie phy */ 88 struct device *pd_pcie_phy; 89 const struct imx6_pcie_drvdata *drvdata; 90 }; 91 92 /* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */ 93 #define PHY_PLL_LOCK_WAIT_USLEEP_MAX 200 94 #define PHY_PLL_LOCK_WAIT_TIMEOUT (2000 * PHY_PLL_LOCK_WAIT_USLEEP_MAX) 95 96 /* PCIe Port Logic registers (memory-mapped) */ 97 #define PL_OFFSET 0x700 98 99 #define PCIE_PHY_CTRL (PL_OFFSET + 0x114) 100 #define PCIE_PHY_CTRL_DATA(x) FIELD_PREP(GENMASK(15, 0), (x)) 101 #define PCIE_PHY_CTRL_CAP_ADR BIT(16) 102 #define PCIE_PHY_CTRL_CAP_DAT BIT(17) 103 #define PCIE_PHY_CTRL_WR BIT(18) 104 #define PCIE_PHY_CTRL_RD BIT(19) 105 106 #define PCIE_PHY_STAT (PL_OFFSET + 0x110) 107 #define PCIE_PHY_STAT_ACK BIT(16) 108 109 /* PHY registers (not memory-mapped) */ 110 #define PCIE_PHY_ATEOVRD 0x10 111 #define PCIE_PHY_ATEOVRD_EN BIT(2) 112 #define PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT 0 113 #define PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK 0x1 114 115 #define PCIE_PHY_MPLL_OVRD_IN_LO 0x11 116 #define PCIE_PHY_MPLL_MULTIPLIER_SHIFT 2 117 #define PCIE_PHY_MPLL_MULTIPLIER_MASK 0x7f 118 #define PCIE_PHY_MPLL_MULTIPLIER_OVRD BIT(9) 119 120 #define PCIE_PHY_RX_ASIC_OUT 0x100D 121 #define PCIE_PHY_RX_ASIC_OUT_VALID (1 << 0) 122 123 /* iMX7 PCIe PHY registers */ 124 #define PCIE_PHY_CMN_REG4 0x14 125 /* These are probably the bits that *aren't* DCC_FB_EN */ 126 #define PCIE_PHY_CMN_REG4_DCC_FB_EN 0x29 127 128 #define PCIE_PHY_CMN_REG15 0x54 129 #define PCIE_PHY_CMN_REG15_DLY_4 BIT(2) 130 #define PCIE_PHY_CMN_REG15_PLL_PD BIT(5) 131 #define PCIE_PHY_CMN_REG15_OVRD_PLL_PD BIT(7) 132 133 #define PCIE_PHY_CMN_REG24 0x90 134 #define PCIE_PHY_CMN_REG24_RX_EQ BIT(6) 135 #define PCIE_PHY_CMN_REG24_RX_EQ_SEL BIT(3) 136 137 #define PCIE_PHY_CMN_REG26 0x98 138 #define PCIE_PHY_CMN_REG26_ATT_MODE 0xBC 139 140 #define PHY_RX_OVRD_IN_LO 0x1005 141 #define PHY_RX_OVRD_IN_LO_RX_DATA_EN BIT(5) 142 #define PHY_RX_OVRD_IN_LO_RX_PLL_EN BIT(3) 143 144 static int pcie_phy_poll_ack(struct imx6_pcie *imx6_pcie, bool exp_val) 145 { 146 struct dw_pcie *pci = imx6_pcie->pci; 147 bool val; 148 u32 max_iterations = 10; 149 u32 wait_counter = 0; 150 151 do { 152 val = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT) & 153 PCIE_PHY_STAT_ACK; 154 wait_counter++; 155 156 if (val == exp_val) 157 return 0; 158 159 udelay(1); 160 } while (wait_counter < max_iterations); 161 162 return -ETIMEDOUT; 163 } 164 165 static int pcie_phy_wait_ack(struct imx6_pcie *imx6_pcie, int addr) 166 { 167 struct dw_pcie *pci = imx6_pcie->pci; 168 u32 val; 169 int ret; 170 171 val = PCIE_PHY_CTRL_DATA(addr); 172 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val); 173 174 val |= PCIE_PHY_CTRL_CAP_ADR; 175 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val); 176 177 ret = pcie_phy_poll_ack(imx6_pcie, true); 178 if (ret) 179 return ret; 180 181 val = PCIE_PHY_CTRL_DATA(addr); 182 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val); 183 184 return pcie_phy_poll_ack(imx6_pcie, false); 185 } 186 187 /* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */ 188 static int pcie_phy_read(struct imx6_pcie *imx6_pcie, int addr, u16 *data) 189 { 190 struct dw_pcie *pci = imx6_pcie->pci; 191 u32 phy_ctl; 192 int ret; 193 194 ret = pcie_phy_wait_ack(imx6_pcie, addr); 195 if (ret) 196 return ret; 197 198 /* assert Read signal */ 199 phy_ctl = PCIE_PHY_CTRL_RD; 200 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, phy_ctl); 201 202 ret = pcie_phy_poll_ack(imx6_pcie, true); 203 if (ret) 204 return ret; 205 206 *data = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT); 207 208 /* deassert Read signal */ 209 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x00); 210 211 return pcie_phy_poll_ack(imx6_pcie, false); 212 } 213 214 static int pcie_phy_write(struct imx6_pcie *imx6_pcie, int addr, u16 data) 215 { 216 struct dw_pcie *pci = imx6_pcie->pci; 217 u32 var; 218 int ret; 219 220 /* write addr */ 221 /* cap addr */ 222 ret = pcie_phy_wait_ack(imx6_pcie, addr); 223 if (ret) 224 return ret; 225 226 var = PCIE_PHY_CTRL_DATA(data); 227 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var); 228 229 /* capture data */ 230 var |= PCIE_PHY_CTRL_CAP_DAT; 231 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var); 232 233 ret = pcie_phy_poll_ack(imx6_pcie, true); 234 if (ret) 235 return ret; 236 237 /* deassert cap data */ 238 var = PCIE_PHY_CTRL_DATA(data); 239 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var); 240 241 /* wait for ack de-assertion */ 242 ret = pcie_phy_poll_ack(imx6_pcie, false); 243 if (ret) 244 return ret; 245 246 /* assert wr signal */ 247 var = PCIE_PHY_CTRL_WR; 248 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var); 249 250 /* wait for ack */ 251 ret = pcie_phy_poll_ack(imx6_pcie, true); 252 if (ret) 253 return ret; 254 255 /* deassert wr signal */ 256 var = PCIE_PHY_CTRL_DATA(data); 257 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var); 258 259 /* wait for ack de-assertion */ 260 ret = pcie_phy_poll_ack(imx6_pcie, false); 261 if (ret) 262 return ret; 263 264 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x0); 265 266 return 0; 267 } 268 269 static void imx6_pcie_reset_phy(struct imx6_pcie *imx6_pcie) 270 { 271 u16 tmp; 272 273 if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY)) 274 return; 275 276 pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp); 277 tmp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN | 278 PHY_RX_OVRD_IN_LO_RX_PLL_EN); 279 pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp); 280 281 usleep_range(2000, 3000); 282 283 pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp); 284 tmp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN | 285 PHY_RX_OVRD_IN_LO_RX_PLL_EN); 286 pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp); 287 } 288 289 #ifdef CONFIG_ARM 290 /* Added for PCI abort handling */ 291 static int imx6q_pcie_abort_handler(unsigned long addr, 292 unsigned int fsr, struct pt_regs *regs) 293 { 294 unsigned long pc = instruction_pointer(regs); 295 unsigned long instr = *(unsigned long *)pc; 296 int reg = (instr >> 12) & 15; 297 298 /* 299 * If the instruction being executed was a read, 300 * make it look like it read all-ones. 301 */ 302 if ((instr & 0x0c100000) == 0x04100000) { 303 unsigned long val; 304 305 if (instr & 0x00400000) 306 val = 255; 307 else 308 val = -1; 309 310 regs->uregs[reg] = val; 311 regs->ARM_pc += 4; 312 return 0; 313 } 314 315 if ((instr & 0x0e100090) == 0x00100090) { 316 regs->uregs[reg] = -1; 317 regs->ARM_pc += 4; 318 return 0; 319 } 320 321 return 1; 322 } 323 #endif 324 325 static int imx6_pcie_attach_pd(struct device *dev) 326 { 327 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); 328 struct device_link *link; 329 330 /* Do nothing when in a single power domain */ 331 if (dev->pm_domain) 332 return 0; 333 334 imx6_pcie->pd_pcie = dev_pm_domain_attach_by_name(dev, "pcie"); 335 if (IS_ERR(imx6_pcie->pd_pcie)) 336 return PTR_ERR(imx6_pcie->pd_pcie); 337 /* Do nothing when power domain missing */ 338 if (!imx6_pcie->pd_pcie) 339 return 0; 340 link = device_link_add(dev, imx6_pcie->pd_pcie, 341 DL_FLAG_STATELESS | 342 DL_FLAG_PM_RUNTIME | 343 DL_FLAG_RPM_ACTIVE); 344 if (!link) { 345 dev_err(dev, "Failed to add device_link to pcie pd.\n"); 346 return -EINVAL; 347 } 348 349 imx6_pcie->pd_pcie_phy = dev_pm_domain_attach_by_name(dev, "pcie_phy"); 350 if (IS_ERR(imx6_pcie->pd_pcie_phy)) 351 return PTR_ERR(imx6_pcie->pd_pcie_phy); 352 353 link = device_link_add(dev, imx6_pcie->pd_pcie_phy, 354 DL_FLAG_STATELESS | 355 DL_FLAG_PM_RUNTIME | 356 DL_FLAG_RPM_ACTIVE); 357 if (!link) { 358 dev_err(dev, "Failed to add device_link to pcie_phy pd.\n"); 359 return -EINVAL; 360 } 361 362 return 0; 363 } 364 365 static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie) 366 { 367 struct device *dev = imx6_pcie->pci->dev; 368 369 switch (imx6_pcie->drvdata->variant) { 370 case IMX7D: 371 case IMX8MQ: 372 reset_control_assert(imx6_pcie->pciephy_reset); 373 reset_control_assert(imx6_pcie->apps_reset); 374 break; 375 case IMX6SX: 376 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, 377 IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 378 IMX6SX_GPR12_PCIE_TEST_POWERDOWN); 379 /* Force PCIe PHY reset */ 380 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5, 381 IMX6SX_GPR5_PCIE_BTNRST_RESET, 382 IMX6SX_GPR5_PCIE_BTNRST_RESET); 383 break; 384 case IMX6QP: 385 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, 386 IMX6Q_GPR1_PCIE_SW_RST, 387 IMX6Q_GPR1_PCIE_SW_RST); 388 break; 389 case IMX6Q: 390 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, 391 IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18); 392 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, 393 IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16); 394 break; 395 } 396 397 if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) { 398 int ret = regulator_disable(imx6_pcie->vpcie); 399 400 if (ret) 401 dev_err(dev, "failed to disable vpcie regulator: %d\n", 402 ret); 403 } 404 } 405 406 static unsigned int imx6_pcie_grp_offset(const struct imx6_pcie *imx6_pcie) 407 { 408 WARN_ON(imx6_pcie->drvdata->variant != IMX8MQ); 409 return imx6_pcie->controller_id == 1 ? IOMUXC_GPR16 : IOMUXC_GPR14; 410 } 411 412 static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie) 413 { 414 struct dw_pcie *pci = imx6_pcie->pci; 415 struct device *dev = pci->dev; 416 unsigned int offset; 417 int ret = 0; 418 419 switch (imx6_pcie->drvdata->variant) { 420 case IMX6SX: 421 ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi); 422 if (ret) { 423 dev_err(dev, "unable to enable pcie_axi clock\n"); 424 break; 425 } 426 427 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, 428 IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0); 429 break; 430 case IMX6QP: 431 case IMX6Q: 432 /* power up core phy and enable ref clock */ 433 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, 434 IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18); 435 /* 436 * the async reset input need ref clock to sync internally, 437 * when the ref clock comes after reset, internal synced 438 * reset time is too short, cannot meet the requirement. 439 * add one ~10us delay here. 440 */ 441 usleep_range(10, 100); 442 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, 443 IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16); 444 break; 445 case IMX7D: 446 break; 447 case IMX8MQ: 448 ret = clk_prepare_enable(imx6_pcie->pcie_aux); 449 if (ret) { 450 dev_err(dev, "unable to enable pcie_aux clock\n"); 451 break; 452 } 453 454 offset = imx6_pcie_grp_offset(imx6_pcie); 455 /* 456 * Set the over ride low and enabled 457 * make sure that REF_CLK is turned on. 458 */ 459 regmap_update_bits(imx6_pcie->iomuxc_gpr, offset, 460 IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE, 461 0); 462 regmap_update_bits(imx6_pcie->iomuxc_gpr, offset, 463 IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN, 464 IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN); 465 break; 466 } 467 468 return ret; 469 } 470 471 static void imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie *imx6_pcie) 472 { 473 u32 val; 474 struct device *dev = imx6_pcie->pci->dev; 475 476 if (regmap_read_poll_timeout(imx6_pcie->iomuxc_gpr, 477 IOMUXC_GPR22, val, 478 val & IMX7D_GPR22_PCIE_PHY_PLL_LOCKED, 479 PHY_PLL_LOCK_WAIT_USLEEP_MAX, 480 PHY_PLL_LOCK_WAIT_TIMEOUT)) 481 dev_err(dev, "PCIe PLL lock timeout\n"); 482 } 483 484 static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie) 485 { 486 struct dw_pcie *pci = imx6_pcie->pci; 487 struct device *dev = pci->dev; 488 int ret; 489 490 if (imx6_pcie->vpcie && !regulator_is_enabled(imx6_pcie->vpcie)) { 491 ret = regulator_enable(imx6_pcie->vpcie); 492 if (ret) { 493 dev_err(dev, "failed to enable vpcie regulator: %d\n", 494 ret); 495 return; 496 } 497 } 498 499 ret = clk_prepare_enable(imx6_pcie->pcie_phy); 500 if (ret) { 501 dev_err(dev, "unable to enable pcie_phy clock\n"); 502 goto err_pcie_phy; 503 } 504 505 ret = clk_prepare_enable(imx6_pcie->pcie_bus); 506 if (ret) { 507 dev_err(dev, "unable to enable pcie_bus clock\n"); 508 goto err_pcie_bus; 509 } 510 511 ret = clk_prepare_enable(imx6_pcie->pcie); 512 if (ret) { 513 dev_err(dev, "unable to enable pcie clock\n"); 514 goto err_pcie; 515 } 516 517 ret = imx6_pcie_enable_ref_clk(imx6_pcie); 518 if (ret) { 519 dev_err(dev, "unable to enable pcie ref clock\n"); 520 goto err_ref_clk; 521 } 522 523 /* allow the clocks to stabilize */ 524 usleep_range(200, 500); 525 526 /* Some boards don't have PCIe reset GPIO. */ 527 if (gpio_is_valid(imx6_pcie->reset_gpio)) { 528 gpio_set_value_cansleep(imx6_pcie->reset_gpio, 529 imx6_pcie->gpio_active_high); 530 msleep(100); 531 gpio_set_value_cansleep(imx6_pcie->reset_gpio, 532 !imx6_pcie->gpio_active_high); 533 } 534 535 switch (imx6_pcie->drvdata->variant) { 536 case IMX8MQ: 537 reset_control_deassert(imx6_pcie->pciephy_reset); 538 break; 539 case IMX7D: 540 reset_control_deassert(imx6_pcie->pciephy_reset); 541 542 /* Workaround for ERR010728, failure of PCI-e PLL VCO to 543 * oscillate, especially when cold. This turns off "Duty-cycle 544 * Corrector" and other mysterious undocumented things. 545 */ 546 if (likely(imx6_pcie->phy_base)) { 547 /* De-assert DCC_FB_EN */ 548 writel(PCIE_PHY_CMN_REG4_DCC_FB_EN, 549 imx6_pcie->phy_base + PCIE_PHY_CMN_REG4); 550 /* Assert RX_EQS and RX_EQS_SEL */ 551 writel(PCIE_PHY_CMN_REG24_RX_EQ_SEL 552 | PCIE_PHY_CMN_REG24_RX_EQ, 553 imx6_pcie->phy_base + PCIE_PHY_CMN_REG24); 554 /* Assert ATT_MODE */ 555 writel(PCIE_PHY_CMN_REG26_ATT_MODE, 556 imx6_pcie->phy_base + PCIE_PHY_CMN_REG26); 557 } else { 558 dev_warn(dev, "Unable to apply ERR010728 workaround. DT missing fsl,imx7d-pcie-phy phandle ?\n"); 559 } 560 561 imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie); 562 break; 563 case IMX6SX: 564 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5, 565 IMX6SX_GPR5_PCIE_BTNRST_RESET, 0); 566 break; 567 case IMX6QP: 568 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, 569 IMX6Q_GPR1_PCIE_SW_RST, 0); 570 571 usleep_range(200, 500); 572 break; 573 case IMX6Q: /* Nothing to do */ 574 break; 575 } 576 577 return; 578 579 err_ref_clk: 580 clk_disable_unprepare(imx6_pcie->pcie); 581 err_pcie: 582 clk_disable_unprepare(imx6_pcie->pcie_bus); 583 err_pcie_bus: 584 clk_disable_unprepare(imx6_pcie->pcie_phy); 585 err_pcie_phy: 586 if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) { 587 ret = regulator_disable(imx6_pcie->vpcie); 588 if (ret) 589 dev_err(dev, "failed to disable vpcie regulator: %d\n", 590 ret); 591 } 592 } 593 594 static void imx6_pcie_configure_type(struct imx6_pcie *imx6_pcie) 595 { 596 unsigned int mask, val; 597 598 if (imx6_pcie->drvdata->variant == IMX8MQ && 599 imx6_pcie->controller_id == 1) { 600 mask = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE; 601 val = FIELD_PREP(IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE, 602 PCI_EXP_TYPE_ROOT_PORT); 603 } else { 604 mask = IMX6Q_GPR12_DEVICE_TYPE; 605 val = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE, 606 PCI_EXP_TYPE_ROOT_PORT); 607 } 608 609 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, mask, val); 610 } 611 612 static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie) 613 { 614 switch (imx6_pcie->drvdata->variant) { 615 case IMX8MQ: 616 /* 617 * TODO: Currently this code assumes external 618 * oscillator is being used 619 */ 620 regmap_update_bits(imx6_pcie->iomuxc_gpr, 621 imx6_pcie_grp_offset(imx6_pcie), 622 IMX8MQ_GPR_PCIE_REF_USE_PAD, 623 IMX8MQ_GPR_PCIE_REF_USE_PAD); 624 break; 625 case IMX7D: 626 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, 627 IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0); 628 break; 629 case IMX6SX: 630 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, 631 IMX6SX_GPR12_PCIE_RX_EQ_MASK, 632 IMX6SX_GPR12_PCIE_RX_EQ_2); 633 fallthrough; 634 default: 635 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, 636 IMX6Q_GPR12_PCIE_CTL_2, 0 << 10); 637 638 /* configure constant input signal to the pcie ctrl and phy */ 639 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, 640 IMX6Q_GPR12_LOS_LEVEL, 9 << 4); 641 642 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, 643 IMX6Q_GPR8_TX_DEEMPH_GEN1, 644 imx6_pcie->tx_deemph_gen1 << 0); 645 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, 646 IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB, 647 imx6_pcie->tx_deemph_gen2_3p5db << 6); 648 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, 649 IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB, 650 imx6_pcie->tx_deemph_gen2_6db << 12); 651 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, 652 IMX6Q_GPR8_TX_SWING_FULL, 653 imx6_pcie->tx_swing_full << 18); 654 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, 655 IMX6Q_GPR8_TX_SWING_LOW, 656 imx6_pcie->tx_swing_low << 25); 657 break; 658 } 659 660 imx6_pcie_configure_type(imx6_pcie); 661 } 662 663 static int imx6_setup_phy_mpll(struct imx6_pcie *imx6_pcie) 664 { 665 unsigned long phy_rate = clk_get_rate(imx6_pcie->pcie_phy); 666 int mult, div; 667 u16 val; 668 669 if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY)) 670 return 0; 671 672 switch (phy_rate) { 673 case 125000000: 674 /* 675 * The default settings of the MPLL are for a 125MHz input 676 * clock, so no need to reconfigure anything in that case. 677 */ 678 return 0; 679 case 100000000: 680 mult = 25; 681 div = 0; 682 break; 683 case 200000000: 684 mult = 25; 685 div = 1; 686 break; 687 default: 688 dev_err(imx6_pcie->pci->dev, 689 "Unsupported PHY reference clock rate %lu\n", phy_rate); 690 return -EINVAL; 691 } 692 693 pcie_phy_read(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, &val); 694 val &= ~(PCIE_PHY_MPLL_MULTIPLIER_MASK << 695 PCIE_PHY_MPLL_MULTIPLIER_SHIFT); 696 val |= mult << PCIE_PHY_MPLL_MULTIPLIER_SHIFT; 697 val |= PCIE_PHY_MPLL_MULTIPLIER_OVRD; 698 pcie_phy_write(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, val); 699 700 pcie_phy_read(imx6_pcie, PCIE_PHY_ATEOVRD, &val); 701 val &= ~(PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK << 702 PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT); 703 val |= div << PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT; 704 val |= PCIE_PHY_ATEOVRD_EN; 705 pcie_phy_write(imx6_pcie, PCIE_PHY_ATEOVRD, val); 706 707 return 0; 708 } 709 710 static int imx6_pcie_wait_for_speed_change(struct imx6_pcie *imx6_pcie) 711 { 712 struct dw_pcie *pci = imx6_pcie->pci; 713 struct device *dev = pci->dev; 714 u32 tmp; 715 unsigned int retries; 716 717 for (retries = 0; retries < 200; retries++) { 718 tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL); 719 /* Test if the speed change finished. */ 720 if (!(tmp & PORT_LOGIC_SPEED_CHANGE)) 721 return 0; 722 usleep_range(100, 1000); 723 } 724 725 dev_err(dev, "Speed change timeout\n"); 726 return -ETIMEDOUT; 727 } 728 729 static void imx6_pcie_ltssm_enable(struct device *dev) 730 { 731 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); 732 733 switch (imx6_pcie->drvdata->variant) { 734 case IMX6Q: 735 case IMX6SX: 736 case IMX6QP: 737 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, 738 IMX6Q_GPR12_PCIE_CTL_2, 739 IMX6Q_GPR12_PCIE_CTL_2); 740 break; 741 case IMX7D: 742 case IMX8MQ: 743 reset_control_deassert(imx6_pcie->apps_reset); 744 break; 745 } 746 } 747 748 static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie) 749 { 750 struct dw_pcie *pci = imx6_pcie->pci; 751 struct device *dev = pci->dev; 752 u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP); 753 u32 tmp; 754 int ret; 755 756 /* 757 * Force Gen1 operation when starting the link. In case the link is 758 * started in Gen2 mode, there is a possibility the devices on the 759 * bus will not be detected at all. This happens with PCIe switches. 760 */ 761 tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP); 762 tmp &= ~PCI_EXP_LNKCAP_SLS; 763 tmp |= PCI_EXP_LNKCAP_SLS_2_5GB; 764 dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp); 765 766 /* Start LTSSM. */ 767 imx6_pcie_ltssm_enable(dev); 768 769 ret = dw_pcie_wait_for_link(pci); 770 if (ret) 771 goto err_reset_phy; 772 773 if (pci->link_gen == 2) { 774 /* Allow Gen2 mode after the link is up. */ 775 tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP); 776 tmp &= ~PCI_EXP_LNKCAP_SLS; 777 tmp |= PCI_EXP_LNKCAP_SLS_5_0GB; 778 dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp); 779 780 /* 781 * Start Directed Speed Change so the best possible 782 * speed both link partners support can be negotiated. 783 */ 784 tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL); 785 tmp |= PORT_LOGIC_SPEED_CHANGE; 786 dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp); 787 788 if (imx6_pcie->drvdata->flags & 789 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE) { 790 /* 791 * On i.MX7, DIRECT_SPEED_CHANGE behaves differently 792 * from i.MX6 family when no link speed transition 793 * occurs and we go Gen1 -> yep, Gen1. The difference 794 * is that, in such case, it will not be cleared by HW 795 * which will cause the following code to report false 796 * failure. 797 */ 798 799 ret = imx6_pcie_wait_for_speed_change(imx6_pcie); 800 if (ret) { 801 dev_err(dev, "Failed to bring link up!\n"); 802 goto err_reset_phy; 803 } 804 } 805 806 /* Make sure link training is finished as well! */ 807 ret = dw_pcie_wait_for_link(pci); 808 if (ret) { 809 dev_err(dev, "Failed to bring link up!\n"); 810 goto err_reset_phy; 811 } 812 } else { 813 dev_info(dev, "Link: Gen2 disabled\n"); 814 } 815 816 tmp = dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKSTA); 817 dev_info(dev, "Link up, Gen%i\n", tmp & PCI_EXP_LNKSTA_CLS); 818 return 0; 819 820 err_reset_phy: 821 dev_dbg(dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n", 822 dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG0), 823 dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG1)); 824 imx6_pcie_reset_phy(imx6_pcie); 825 return ret; 826 } 827 828 static int imx6_pcie_host_init(struct pcie_port *pp) 829 { 830 struct dw_pcie *pci = to_dw_pcie_from_pp(pp); 831 struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci); 832 833 imx6_pcie_assert_core_reset(imx6_pcie); 834 imx6_pcie_init_phy(imx6_pcie); 835 imx6_pcie_deassert_core_reset(imx6_pcie); 836 imx6_setup_phy_mpll(imx6_pcie); 837 dw_pcie_setup_rc(pp); 838 imx6_pcie_establish_link(imx6_pcie); 839 dw_pcie_msi_init(pp); 840 841 return 0; 842 } 843 844 static const struct dw_pcie_host_ops imx6_pcie_host_ops = { 845 .host_init = imx6_pcie_host_init, 846 }; 847 848 static int imx6_add_pcie_port(struct imx6_pcie *imx6_pcie, 849 struct platform_device *pdev) 850 { 851 struct dw_pcie *pci = imx6_pcie->pci; 852 struct pcie_port *pp = &pci->pp; 853 struct device *dev = &pdev->dev; 854 int ret; 855 856 if (IS_ENABLED(CONFIG_PCI_MSI)) { 857 pp->msi_irq = platform_get_irq_byname(pdev, "msi"); 858 if (pp->msi_irq < 0) 859 return pp->msi_irq; 860 } 861 862 pp->ops = &imx6_pcie_host_ops; 863 864 ret = dw_pcie_host_init(pp); 865 if (ret) { 866 dev_err(dev, "failed to initialize host\n"); 867 return ret; 868 } 869 870 return 0; 871 } 872 873 static const struct dw_pcie_ops dw_pcie_ops = { 874 /* No special ops needed, but pcie-designware still expects this struct */ 875 }; 876 877 #ifdef CONFIG_PM_SLEEP 878 static void imx6_pcie_ltssm_disable(struct device *dev) 879 { 880 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); 881 882 switch (imx6_pcie->drvdata->variant) { 883 case IMX6SX: 884 case IMX6QP: 885 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, 886 IMX6Q_GPR12_PCIE_CTL_2, 0); 887 break; 888 case IMX7D: 889 reset_control_assert(imx6_pcie->apps_reset); 890 break; 891 default: 892 dev_err(dev, "ltssm_disable not supported\n"); 893 } 894 } 895 896 static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie) 897 { 898 struct device *dev = imx6_pcie->pci->dev; 899 900 /* Some variants have a turnoff reset in DT */ 901 if (imx6_pcie->turnoff_reset) { 902 reset_control_assert(imx6_pcie->turnoff_reset); 903 reset_control_deassert(imx6_pcie->turnoff_reset); 904 goto pm_turnoff_sleep; 905 } 906 907 /* Others poke directly at IOMUXC registers */ 908 switch (imx6_pcie->drvdata->variant) { 909 case IMX6SX: 910 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, 911 IMX6SX_GPR12_PCIE_PM_TURN_OFF, 912 IMX6SX_GPR12_PCIE_PM_TURN_OFF); 913 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, 914 IMX6SX_GPR12_PCIE_PM_TURN_OFF, 0); 915 break; 916 default: 917 dev_err(dev, "PME_Turn_Off not implemented\n"); 918 return; 919 } 920 921 /* 922 * Components with an upstream port must respond to 923 * PME_Turn_Off with PME_TO_Ack but we can't check. 924 * 925 * The standard recommends a 1-10ms timeout after which to 926 * proceed anyway as if acks were received. 927 */ 928 pm_turnoff_sleep: 929 usleep_range(1000, 10000); 930 } 931 932 static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie) 933 { 934 clk_disable_unprepare(imx6_pcie->pcie); 935 clk_disable_unprepare(imx6_pcie->pcie_phy); 936 clk_disable_unprepare(imx6_pcie->pcie_bus); 937 938 switch (imx6_pcie->drvdata->variant) { 939 case IMX6SX: 940 clk_disable_unprepare(imx6_pcie->pcie_inbound_axi); 941 break; 942 case IMX7D: 943 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, 944 IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 945 IMX7D_GPR12_PCIE_PHY_REFCLK_SEL); 946 break; 947 case IMX8MQ: 948 clk_disable_unprepare(imx6_pcie->pcie_aux); 949 break; 950 default: 951 break; 952 } 953 } 954 955 static int imx6_pcie_suspend_noirq(struct device *dev) 956 { 957 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); 958 959 if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND)) 960 return 0; 961 962 imx6_pcie_pm_turnoff(imx6_pcie); 963 imx6_pcie_clk_disable(imx6_pcie); 964 imx6_pcie_ltssm_disable(dev); 965 966 return 0; 967 } 968 969 static int imx6_pcie_resume_noirq(struct device *dev) 970 { 971 int ret; 972 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); 973 struct pcie_port *pp = &imx6_pcie->pci->pp; 974 975 if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND)) 976 return 0; 977 978 imx6_pcie_assert_core_reset(imx6_pcie); 979 imx6_pcie_init_phy(imx6_pcie); 980 imx6_pcie_deassert_core_reset(imx6_pcie); 981 dw_pcie_setup_rc(pp); 982 983 ret = imx6_pcie_establish_link(imx6_pcie); 984 if (ret < 0) 985 dev_info(dev, "pcie link is down after resume.\n"); 986 987 return 0; 988 } 989 #endif 990 991 static const struct dev_pm_ops imx6_pcie_pm_ops = { 992 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx6_pcie_suspend_noirq, 993 imx6_pcie_resume_noirq) 994 }; 995 996 static int imx6_pcie_probe(struct platform_device *pdev) 997 { 998 struct device *dev = &pdev->dev; 999 struct dw_pcie *pci; 1000 struct imx6_pcie *imx6_pcie; 1001 struct device_node *np; 1002 struct resource *dbi_base; 1003 struct device_node *node = dev->of_node; 1004 int ret; 1005 u16 val; 1006 1007 imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL); 1008 if (!imx6_pcie) 1009 return -ENOMEM; 1010 1011 pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL); 1012 if (!pci) 1013 return -ENOMEM; 1014 1015 pci->dev = dev; 1016 pci->ops = &dw_pcie_ops; 1017 1018 imx6_pcie->pci = pci; 1019 imx6_pcie->drvdata = of_device_get_match_data(dev); 1020 1021 /* Find the PHY if one is defined, only imx7d uses it */ 1022 np = of_parse_phandle(node, "fsl,imx7d-pcie-phy", 0); 1023 if (np) { 1024 struct resource res; 1025 1026 ret = of_address_to_resource(np, 0, &res); 1027 if (ret) { 1028 dev_err(dev, "Unable to map PCIe PHY\n"); 1029 return ret; 1030 } 1031 imx6_pcie->phy_base = devm_ioremap_resource(dev, &res); 1032 if (IS_ERR(imx6_pcie->phy_base)) { 1033 dev_err(dev, "Unable to map PCIe PHY\n"); 1034 return PTR_ERR(imx6_pcie->phy_base); 1035 } 1036 } 1037 1038 dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0); 1039 pci->dbi_base = devm_ioremap_resource(dev, dbi_base); 1040 if (IS_ERR(pci->dbi_base)) 1041 return PTR_ERR(pci->dbi_base); 1042 1043 /* Fetch GPIOs */ 1044 imx6_pcie->reset_gpio = of_get_named_gpio(node, "reset-gpio", 0); 1045 imx6_pcie->gpio_active_high = of_property_read_bool(node, 1046 "reset-gpio-active-high"); 1047 if (gpio_is_valid(imx6_pcie->reset_gpio)) { 1048 ret = devm_gpio_request_one(dev, imx6_pcie->reset_gpio, 1049 imx6_pcie->gpio_active_high ? 1050 GPIOF_OUT_INIT_HIGH : 1051 GPIOF_OUT_INIT_LOW, 1052 "PCIe reset"); 1053 if (ret) { 1054 dev_err(dev, "unable to get reset gpio\n"); 1055 return ret; 1056 } 1057 } else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) { 1058 return imx6_pcie->reset_gpio; 1059 } 1060 1061 /* Fetch clocks */ 1062 imx6_pcie->pcie_phy = devm_clk_get(dev, "pcie_phy"); 1063 if (IS_ERR(imx6_pcie->pcie_phy)) 1064 return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_phy), 1065 "pcie_phy clock source missing or invalid\n"); 1066 1067 imx6_pcie->pcie_bus = devm_clk_get(dev, "pcie_bus"); 1068 if (IS_ERR(imx6_pcie->pcie_bus)) 1069 return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_bus), 1070 "pcie_bus clock source missing or invalid\n"); 1071 1072 imx6_pcie->pcie = devm_clk_get(dev, "pcie"); 1073 if (IS_ERR(imx6_pcie->pcie)) 1074 return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie), 1075 "pcie clock source missing or invalid\n"); 1076 1077 switch (imx6_pcie->drvdata->variant) { 1078 case IMX6SX: 1079 imx6_pcie->pcie_inbound_axi = devm_clk_get(dev, 1080 "pcie_inbound_axi"); 1081 if (IS_ERR(imx6_pcie->pcie_inbound_axi)) 1082 return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_inbound_axi), 1083 "pcie_inbound_axi clock missing or invalid\n"); 1084 break; 1085 case IMX8MQ: 1086 imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux"); 1087 if (IS_ERR(imx6_pcie->pcie_aux)) 1088 return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_aux), 1089 "pcie_aux clock source missing or invalid\n"); 1090 fallthrough; 1091 case IMX7D: 1092 if (dbi_base->start == IMX8MQ_PCIE2_BASE_ADDR) 1093 imx6_pcie->controller_id = 1; 1094 1095 imx6_pcie->pciephy_reset = devm_reset_control_get_exclusive(dev, 1096 "pciephy"); 1097 if (IS_ERR(imx6_pcie->pciephy_reset)) { 1098 dev_err(dev, "Failed to get PCIEPHY reset control\n"); 1099 return PTR_ERR(imx6_pcie->pciephy_reset); 1100 } 1101 1102 imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev, 1103 "apps"); 1104 if (IS_ERR(imx6_pcie->apps_reset)) { 1105 dev_err(dev, "Failed to get PCIE APPS reset control\n"); 1106 return PTR_ERR(imx6_pcie->apps_reset); 1107 } 1108 break; 1109 default: 1110 break; 1111 } 1112 1113 /* Grab turnoff reset */ 1114 imx6_pcie->turnoff_reset = devm_reset_control_get_optional_exclusive(dev, "turnoff"); 1115 if (IS_ERR(imx6_pcie->turnoff_reset)) { 1116 dev_err(dev, "Failed to get TURNOFF reset control\n"); 1117 return PTR_ERR(imx6_pcie->turnoff_reset); 1118 } 1119 1120 /* Grab GPR config register range */ 1121 imx6_pcie->iomuxc_gpr = 1122 syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr"); 1123 if (IS_ERR(imx6_pcie->iomuxc_gpr)) { 1124 dev_err(dev, "unable to find iomuxc registers\n"); 1125 return PTR_ERR(imx6_pcie->iomuxc_gpr); 1126 } 1127 1128 /* Grab PCIe PHY Tx Settings */ 1129 if (of_property_read_u32(node, "fsl,tx-deemph-gen1", 1130 &imx6_pcie->tx_deemph_gen1)) 1131 imx6_pcie->tx_deemph_gen1 = 0; 1132 1133 if (of_property_read_u32(node, "fsl,tx-deemph-gen2-3p5db", 1134 &imx6_pcie->tx_deemph_gen2_3p5db)) 1135 imx6_pcie->tx_deemph_gen2_3p5db = 0; 1136 1137 if (of_property_read_u32(node, "fsl,tx-deemph-gen2-6db", 1138 &imx6_pcie->tx_deemph_gen2_6db)) 1139 imx6_pcie->tx_deemph_gen2_6db = 20; 1140 1141 if (of_property_read_u32(node, "fsl,tx-swing-full", 1142 &imx6_pcie->tx_swing_full)) 1143 imx6_pcie->tx_swing_full = 127; 1144 1145 if (of_property_read_u32(node, "fsl,tx-swing-low", 1146 &imx6_pcie->tx_swing_low)) 1147 imx6_pcie->tx_swing_low = 127; 1148 1149 /* Limit link speed */ 1150 pci->link_gen = 1; 1151 ret = of_property_read_u32(node, "fsl,max-link-speed", &pci->link_gen); 1152 1153 imx6_pcie->vpcie = devm_regulator_get_optional(&pdev->dev, "vpcie"); 1154 if (IS_ERR(imx6_pcie->vpcie)) { 1155 if (PTR_ERR(imx6_pcie->vpcie) != -ENODEV) 1156 return PTR_ERR(imx6_pcie->vpcie); 1157 imx6_pcie->vpcie = NULL; 1158 } 1159 1160 platform_set_drvdata(pdev, imx6_pcie); 1161 1162 ret = imx6_pcie_attach_pd(dev); 1163 if (ret) 1164 return ret; 1165 1166 ret = imx6_add_pcie_port(imx6_pcie, pdev); 1167 if (ret < 0) 1168 return ret; 1169 1170 if (pci_msi_enabled()) { 1171 u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI); 1172 val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS); 1173 val |= PCI_MSI_FLAGS_ENABLE; 1174 dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val); 1175 } 1176 1177 return 0; 1178 } 1179 1180 static void imx6_pcie_shutdown(struct platform_device *pdev) 1181 { 1182 struct imx6_pcie *imx6_pcie = platform_get_drvdata(pdev); 1183 1184 /* bring down link, so bootloader gets clean state in case of reboot */ 1185 imx6_pcie_assert_core_reset(imx6_pcie); 1186 } 1187 1188 static const struct imx6_pcie_drvdata drvdata[] = { 1189 [IMX6Q] = { 1190 .variant = IMX6Q, 1191 .flags = IMX6_PCIE_FLAG_IMX6_PHY | 1192 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE, 1193 .dbi_length = 0x200, 1194 }, 1195 [IMX6SX] = { 1196 .variant = IMX6SX, 1197 .flags = IMX6_PCIE_FLAG_IMX6_PHY | 1198 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE | 1199 IMX6_PCIE_FLAG_SUPPORTS_SUSPEND, 1200 }, 1201 [IMX6QP] = { 1202 .variant = IMX6QP, 1203 .flags = IMX6_PCIE_FLAG_IMX6_PHY | 1204 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE, 1205 }, 1206 [IMX7D] = { 1207 .variant = IMX7D, 1208 .flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND, 1209 }, 1210 [IMX8MQ] = { 1211 .variant = IMX8MQ, 1212 }, 1213 }; 1214 1215 static const struct of_device_id imx6_pcie_of_match[] = { 1216 { .compatible = "fsl,imx6q-pcie", .data = &drvdata[IMX6Q], }, 1217 { .compatible = "fsl,imx6sx-pcie", .data = &drvdata[IMX6SX], }, 1218 { .compatible = "fsl,imx6qp-pcie", .data = &drvdata[IMX6QP], }, 1219 { .compatible = "fsl,imx7d-pcie", .data = &drvdata[IMX7D], }, 1220 { .compatible = "fsl,imx8mq-pcie", .data = &drvdata[IMX8MQ], } , 1221 {}, 1222 }; 1223 1224 static struct platform_driver imx6_pcie_driver = { 1225 .driver = { 1226 .name = "imx6q-pcie", 1227 .of_match_table = imx6_pcie_of_match, 1228 .suppress_bind_attrs = true, 1229 .pm = &imx6_pcie_pm_ops, 1230 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 1231 }, 1232 .probe = imx6_pcie_probe, 1233 .shutdown = imx6_pcie_shutdown, 1234 }; 1235 1236 static void imx6_pcie_quirk(struct pci_dev *dev) 1237 { 1238 struct pci_bus *bus = dev->bus; 1239 struct pcie_port *pp = bus->sysdata; 1240 1241 /* Bus parent is the PCI bridge, its parent is this platform driver */ 1242 if (!bus->dev.parent || !bus->dev.parent->parent) 1243 return; 1244 1245 /* Make sure we only quirk devices associated with this driver */ 1246 if (bus->dev.parent->parent->driver != &imx6_pcie_driver.driver) 1247 return; 1248 1249 if (pci_is_root_bus(bus)) { 1250 struct dw_pcie *pci = to_dw_pcie_from_pp(pp); 1251 struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci); 1252 1253 /* 1254 * Limit config length to avoid the kernel reading beyond 1255 * the register set and causing an abort on i.MX 6Quad 1256 */ 1257 if (imx6_pcie->drvdata->dbi_length) { 1258 dev->cfg_size = imx6_pcie->drvdata->dbi_length; 1259 dev_info(&dev->dev, "Limiting cfg_size to %d\n", 1260 dev->cfg_size); 1261 } 1262 } 1263 } 1264 DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_VENDOR_ID_SYNOPSYS, 0xabcd, 1265 PCI_CLASS_BRIDGE_PCI, 8, imx6_pcie_quirk); 1266 1267 static int __init imx6_pcie_init(void) 1268 { 1269 #ifdef CONFIG_ARM 1270 /* 1271 * Since probe() can be deferred we need to make sure that 1272 * hook_fault_code is not called after __init memory is freed 1273 * by kernel and since imx6q_pcie_abort_handler() is a no-op, 1274 * we can install the handler here without risking it 1275 * accessing some uninitialized driver state. 1276 */ 1277 hook_fault_code(8, imx6q_pcie_abort_handler, SIGBUS, 0, 1278 "external abort on non-linefetch"); 1279 #endif 1280 1281 return platform_driver_register(&imx6_pcie_driver); 1282 } 1283 device_initcall(imx6_pcie_init); 1284