// SPDX-License-Identifier: GPL-2.0 /* * PCIe host controller driver for Freescale i.MX6 SoCs * * Copyright (C) 2013 Kosagi * http://www.kosagi.com * * Author: Sean Cross */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "pcie-designware.h" #define IMX8MQ_GPR_PCIE_REF_USE_PAD BIT(9) #define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN BIT(10) #define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE BIT(11) #define IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE GENMASK(11, 8) #define IMX8MQ_PCIE2_BASE_ADDR 0x33c00000 #define to_imx6_pcie(x) dev_get_drvdata((x)->dev) enum imx6_pcie_variants { IMX6Q, IMX6SX, IMX6QP, IMX7D, IMX8MQ, }; #define IMX6_PCIE_FLAG_IMX6_PHY BIT(0) #define IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE BIT(1) struct imx6_pcie_drvdata { enum imx6_pcie_variants variant; u32 flags; }; struct imx6_pcie { struct dw_pcie *pci; int reset_gpio; bool gpio_active_high; struct clk *pcie_bus; struct clk *pcie_phy; struct clk *pcie_inbound_axi; struct clk *pcie; struct clk *pcie_aux; struct regmap *iomuxc_gpr; u32 controller_id; struct reset_control *pciephy_reset; struct reset_control *apps_reset; struct reset_control *turnoff_reset; u32 tx_deemph_gen1; u32 tx_deemph_gen2_3p5db; u32 tx_deemph_gen2_6db; u32 tx_swing_full; u32 tx_swing_low; int link_gen; struct regulator *vpcie; void __iomem *phy_base; /* power domain for pcie */ struct device *pd_pcie; /* power domain for pcie phy */ struct device *pd_pcie_phy; const struct imx6_pcie_drvdata *drvdata; }; /* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */ #define PHY_PLL_LOCK_WAIT_MAX_RETRIES 2000 #define PHY_PLL_LOCK_WAIT_USLEEP_MIN 50 #define PHY_PLL_LOCK_WAIT_USLEEP_MAX 200 /* PCIe Root Complex registers (memory-mapped) */ #define PCIE_RC_IMX6_MSI_CAP 0x50 #define PCIE_RC_LCR 0x7c #define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1 0x1 #define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2 0x2 #define PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK 0xf #define PCIE_RC_LCSR 0x80 /* PCIe Port Logic registers (memory-mapped) */ #define PL_OFFSET 0x700 #define PCIE_PL_PFLR (PL_OFFSET + 0x08) #define PCIE_PL_PFLR_LINK_STATE_MASK (0x3f << 16) #define PCIE_PL_PFLR_FORCE_LINK (1 << 15) #define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28) #define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c) #define PCIE_PHY_CTRL (PL_OFFSET + 0x114) #define PCIE_PHY_CTRL_DATA_LOC 0 #define PCIE_PHY_CTRL_CAP_ADR_LOC 16 #define PCIE_PHY_CTRL_CAP_DAT_LOC 17 #define PCIE_PHY_CTRL_WR_LOC 18 #define PCIE_PHY_CTRL_RD_LOC 19 #define PCIE_PHY_STAT (PL_OFFSET + 0x110) #define PCIE_PHY_STAT_ACK_LOC 16 #define PCIE_LINK_WIDTH_SPEED_CONTROL 0x80C /* PHY registers (not memory-mapped) */ #define PCIE_PHY_ATEOVRD 0x10 #define PCIE_PHY_ATEOVRD_EN (0x1 << 2) #define PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT 0 #define PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK 0x1 #define PCIE_PHY_MPLL_OVRD_IN_LO 0x11 #define PCIE_PHY_MPLL_MULTIPLIER_SHIFT 2 #define PCIE_PHY_MPLL_MULTIPLIER_MASK 0x7f #define PCIE_PHY_MPLL_MULTIPLIER_OVRD (0x1 << 9) #define PCIE_PHY_RX_ASIC_OUT 0x100D #define PCIE_PHY_RX_ASIC_OUT_VALID (1 << 0) /* iMX7 PCIe PHY registers */ #define PCIE_PHY_CMN_REG4 0x14 /* These are probably the bits that *aren't* DCC_FB_EN */ #define PCIE_PHY_CMN_REG4_DCC_FB_EN 0x29 #define PCIE_PHY_CMN_REG15 0x54 #define PCIE_PHY_CMN_REG15_DLY_4 BIT(2) #define PCIE_PHY_CMN_REG15_PLL_PD BIT(5) #define PCIE_PHY_CMN_REG15_OVRD_PLL_PD BIT(7) #define PCIE_PHY_CMN_REG24 0x90 #define PCIE_PHY_CMN_REG24_RX_EQ BIT(6) #define PCIE_PHY_CMN_REG24_RX_EQ_SEL BIT(3) #define PCIE_PHY_CMN_REG26 0x98 #define PCIE_PHY_CMN_REG26_ATT_MODE 0xBC #define PHY_RX_OVRD_IN_LO 0x1005 #define PHY_RX_OVRD_IN_LO_RX_DATA_EN (1 << 5) #define PHY_RX_OVRD_IN_LO_RX_PLL_EN (1 << 3) static int pcie_phy_poll_ack(struct imx6_pcie *imx6_pcie, int exp_val) { struct dw_pcie *pci = imx6_pcie->pci; u32 val; u32 max_iterations = 10; u32 wait_counter = 0; do { val = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT); val = (val >> PCIE_PHY_STAT_ACK_LOC) & 0x1; wait_counter++; if (val == exp_val) return 0; udelay(1); } while (wait_counter < max_iterations); return -ETIMEDOUT; } static int pcie_phy_wait_ack(struct imx6_pcie *imx6_pcie, int addr) { struct dw_pcie *pci = imx6_pcie->pci; u32 val; int ret; val = addr << PCIE_PHY_CTRL_DATA_LOC; dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val); val |= (0x1 << PCIE_PHY_CTRL_CAP_ADR_LOC); dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val); ret = pcie_phy_poll_ack(imx6_pcie, 1); if (ret) return ret; val = addr << PCIE_PHY_CTRL_DATA_LOC; dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val); return pcie_phy_poll_ack(imx6_pcie, 0); } /* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */ static int pcie_phy_read(struct imx6_pcie *imx6_pcie, int addr, int *data) { struct dw_pcie *pci = imx6_pcie->pci; u32 val, phy_ctl; int ret; ret = pcie_phy_wait_ack(imx6_pcie, addr); if (ret) return ret; /* assert Read signal */ phy_ctl = 0x1 << PCIE_PHY_CTRL_RD_LOC; dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, phy_ctl); ret = pcie_phy_poll_ack(imx6_pcie, 1); if (ret) return ret; val = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT); *data = val & 0xffff; /* deassert Read signal */ dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x00); return pcie_phy_poll_ack(imx6_pcie, 0); } static int pcie_phy_write(struct imx6_pcie *imx6_pcie, int addr, int data) { struct dw_pcie *pci = imx6_pcie->pci; u32 var; int ret; /* write addr */ /* cap addr */ ret = pcie_phy_wait_ack(imx6_pcie, addr); if (ret) return ret; var = data << PCIE_PHY_CTRL_DATA_LOC; dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var); /* capture data */ var |= (0x1 << PCIE_PHY_CTRL_CAP_DAT_LOC); dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var); ret = pcie_phy_poll_ack(imx6_pcie, 1); if (ret) return ret; /* deassert cap data */ var = data << PCIE_PHY_CTRL_DATA_LOC; dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var); /* wait for ack de-assertion */ ret = pcie_phy_poll_ack(imx6_pcie, 0); if (ret) return ret; /* assert wr signal */ var = 0x1 << PCIE_PHY_CTRL_WR_LOC; dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var); /* wait for ack */ ret = pcie_phy_poll_ack(imx6_pcie, 1); if (ret) return ret; /* deassert wr signal */ var = data << PCIE_PHY_CTRL_DATA_LOC; dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var); /* wait for ack de-assertion */ ret = pcie_phy_poll_ack(imx6_pcie, 0); if (ret) return ret; dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x0); return 0; } static void imx6_pcie_reset_phy(struct imx6_pcie *imx6_pcie) { u32 tmp; if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY)) return; pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp); tmp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN | PHY_RX_OVRD_IN_LO_RX_PLL_EN); pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp); usleep_range(2000, 3000); pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp); tmp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN | PHY_RX_OVRD_IN_LO_RX_PLL_EN); pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp); } #ifdef CONFIG_ARM /* Added for PCI abort handling */ static int imx6q_pcie_abort_handler(unsigned long addr, unsigned int fsr, struct pt_regs *regs) { unsigned long pc = instruction_pointer(regs); unsigned long instr = *(unsigned long *)pc; int reg = (instr >> 12) & 15; /* * If the instruction being executed was a read, * make it look like it read all-ones. */ if ((instr & 0x0c100000) == 0x04100000) { unsigned long val; if (instr & 0x00400000) val = 255; else val = -1; regs->uregs[reg] = val; regs->ARM_pc += 4; return 0; } if ((instr & 0x0e100090) == 0x00100090) { regs->uregs[reg] = -1; regs->ARM_pc += 4; return 0; } return 1; } #endif static int imx6_pcie_attach_pd(struct device *dev) { struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); struct device_link *link; /* Do nothing when in a single power domain */ if (dev->pm_domain) return 0; imx6_pcie->pd_pcie = dev_pm_domain_attach_by_name(dev, "pcie"); if (IS_ERR(imx6_pcie->pd_pcie)) return PTR_ERR(imx6_pcie->pd_pcie); /* Do nothing when power domain missing */ if (!imx6_pcie->pd_pcie) return 0; link = device_link_add(dev, imx6_pcie->pd_pcie, DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE); if (!link) { dev_err(dev, "Failed to add device_link to pcie pd.\n"); return -EINVAL; } imx6_pcie->pd_pcie_phy = dev_pm_domain_attach_by_name(dev, "pcie_phy"); if (IS_ERR(imx6_pcie->pd_pcie_phy)) return PTR_ERR(imx6_pcie->pd_pcie_phy); link = device_link_add(dev, imx6_pcie->pd_pcie_phy, DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE); if (!link) { dev_err(dev, "Failed to add device_link to pcie_phy pd.\n"); return -EINVAL; } return 0; } static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie) { struct device *dev = imx6_pcie->pci->dev; switch (imx6_pcie->drvdata->variant) { case IMX7D: case IMX8MQ: reset_control_assert(imx6_pcie->pciephy_reset); reset_control_assert(imx6_pcie->apps_reset); break; case IMX6SX: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX6SX_GPR12_PCIE_TEST_POWERDOWN, IMX6SX_GPR12_PCIE_TEST_POWERDOWN); /* Force PCIe PHY reset */ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5, IMX6SX_GPR5_PCIE_BTNRST_RESET, IMX6SX_GPR5_PCIE_BTNRST_RESET); break; case IMX6QP: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_SW_RST, IMX6Q_GPR1_PCIE_SW_RST); break; case IMX6Q: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18); regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16); break; } if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) { int ret = regulator_disable(imx6_pcie->vpcie); if (ret) dev_err(dev, "failed to disable vpcie regulator: %d\n", ret); } } static unsigned int imx6_pcie_grp_offset(const struct imx6_pcie *imx6_pcie) { WARN_ON(imx6_pcie->drvdata->variant != IMX8MQ); return imx6_pcie->controller_id == 1 ? IOMUXC_GPR16 : IOMUXC_GPR14; } static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie) { struct dw_pcie *pci = imx6_pcie->pci; struct device *dev = pci->dev; unsigned int offset; int ret = 0; switch (imx6_pcie->drvdata->variant) { case IMX6SX: ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi); if (ret) { dev_err(dev, "unable to enable pcie_axi clock\n"); break; } regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0); break; case IMX6QP: /* FALLTHROUGH */ case IMX6Q: /* power up core phy and enable ref clock */ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18); /* * the async reset input need ref clock to sync internally, * when the ref clock comes after reset, internal synced * reset time is too short, cannot meet the requirement. * add one ~10us delay here. */ udelay(10); regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16); break; case IMX7D: break; case IMX8MQ: ret = clk_prepare_enable(imx6_pcie->pcie_aux); if (ret) { dev_err(dev, "unable to enable pcie_aux clock\n"); break; } offset = imx6_pcie_grp_offset(imx6_pcie); /* * Set the over ride low and enabled * make sure that REF_CLK is turned on. */ regmap_update_bits(imx6_pcie->iomuxc_gpr, offset, IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE, 0); regmap_update_bits(imx6_pcie->iomuxc_gpr, offset, IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN, IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN); break; } return ret; } static void imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie *imx6_pcie) { u32 val; unsigned int retries; struct device *dev = imx6_pcie->pci->dev; for (retries = 0; retries < PHY_PLL_LOCK_WAIT_MAX_RETRIES; retries++) { regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR22, &val); if (val & IMX7D_GPR22_PCIE_PHY_PLL_LOCKED) return; usleep_range(PHY_PLL_LOCK_WAIT_USLEEP_MIN, PHY_PLL_LOCK_WAIT_USLEEP_MAX); } dev_err(dev, "PCIe PLL lock timeout\n"); } static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie) { struct dw_pcie *pci = imx6_pcie->pci; struct device *dev = pci->dev; int ret; if (imx6_pcie->vpcie && !regulator_is_enabled(imx6_pcie->vpcie)) { ret = regulator_enable(imx6_pcie->vpcie); if (ret) { dev_err(dev, "failed to enable vpcie regulator: %d\n", ret); return; } } ret = clk_prepare_enable(imx6_pcie->pcie_phy); if (ret) { dev_err(dev, "unable to enable pcie_phy clock\n"); goto err_pcie_phy; } ret = clk_prepare_enable(imx6_pcie->pcie_bus); if (ret) { dev_err(dev, "unable to enable pcie_bus clock\n"); goto err_pcie_bus; } ret = clk_prepare_enable(imx6_pcie->pcie); if (ret) { dev_err(dev, "unable to enable pcie clock\n"); goto err_pcie; } ret = imx6_pcie_enable_ref_clk(imx6_pcie); if (ret) { dev_err(dev, "unable to enable pcie ref clock\n"); goto err_ref_clk; } /* allow the clocks to stabilize */ usleep_range(200, 500); /* Some boards don't have PCIe reset GPIO. */ if (gpio_is_valid(imx6_pcie->reset_gpio)) { gpio_set_value_cansleep(imx6_pcie->reset_gpio, imx6_pcie->gpio_active_high); msleep(100); gpio_set_value_cansleep(imx6_pcie->reset_gpio, !imx6_pcie->gpio_active_high); } switch (imx6_pcie->drvdata->variant) { case IMX8MQ: reset_control_deassert(imx6_pcie->pciephy_reset); break; case IMX7D: reset_control_deassert(imx6_pcie->pciephy_reset); /* Workaround for ERR010728, failure of PCI-e PLL VCO to * oscillate, especially when cold. This turns off "Duty-cycle * Corrector" and other mysterious undocumented things. */ if (likely(imx6_pcie->phy_base)) { /* De-assert DCC_FB_EN */ writel(PCIE_PHY_CMN_REG4_DCC_FB_EN, imx6_pcie->phy_base + PCIE_PHY_CMN_REG4); /* Assert RX_EQS and RX_EQS_SEL */ writel(PCIE_PHY_CMN_REG24_RX_EQ_SEL | PCIE_PHY_CMN_REG24_RX_EQ, imx6_pcie->phy_base + PCIE_PHY_CMN_REG24); /* Assert ATT_MODE */ writel(PCIE_PHY_CMN_REG26_ATT_MODE, imx6_pcie->phy_base + PCIE_PHY_CMN_REG26); } else { dev_warn(dev, "Unable to apply ERR010728 workaround. DT missing fsl,imx7d-pcie-phy phandle ?\n"); } imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie); break; case IMX6SX: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5, IMX6SX_GPR5_PCIE_BTNRST_RESET, 0); break; case IMX6QP: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_SW_RST, 0); usleep_range(200, 500); break; case IMX6Q: /* Nothing to do */ break; } return; err_ref_clk: clk_disable_unprepare(imx6_pcie->pcie); err_pcie: clk_disable_unprepare(imx6_pcie->pcie_bus); err_pcie_bus: clk_disable_unprepare(imx6_pcie->pcie_phy); err_pcie_phy: if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) { ret = regulator_disable(imx6_pcie->vpcie); if (ret) dev_err(dev, "failed to disable vpcie regulator: %d\n", ret); } } static void imx6_pcie_configure_type(struct imx6_pcie *imx6_pcie) { unsigned int mask, val; if (imx6_pcie->drvdata->variant == IMX8MQ && imx6_pcie->controller_id == 1) { mask = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE; val = FIELD_PREP(IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE, PCI_EXP_TYPE_ROOT_PORT); } else { mask = IMX6Q_GPR12_DEVICE_TYPE; val = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE, PCI_EXP_TYPE_ROOT_PORT); } regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, mask, val); } static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie) { switch (imx6_pcie->drvdata->variant) { case IMX8MQ: /* * TODO: Currently this code assumes external * oscillator is being used */ regmap_update_bits(imx6_pcie->iomuxc_gpr, imx6_pcie_grp_offset(imx6_pcie), IMX8MQ_GPR_PCIE_REF_USE_PAD, IMX8MQ_GPR_PCIE_REF_USE_PAD); break; case IMX7D: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0); break; case IMX6SX: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX6SX_GPR12_PCIE_RX_EQ_MASK, IMX6SX_GPR12_PCIE_RX_EQ_2); /* FALLTHROUGH */ default: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX6Q_GPR12_PCIE_CTL_2, 0 << 10); /* configure constant input signal to the pcie ctrl and phy */ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX6Q_GPR12_LOS_LEVEL, 9 << 4); regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, IMX6Q_GPR8_TX_DEEMPH_GEN1, imx6_pcie->tx_deemph_gen1 << 0); regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB, imx6_pcie->tx_deemph_gen2_3p5db << 6); regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB, imx6_pcie->tx_deemph_gen2_6db << 12); regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, IMX6Q_GPR8_TX_SWING_FULL, imx6_pcie->tx_swing_full << 18); regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, IMX6Q_GPR8_TX_SWING_LOW, imx6_pcie->tx_swing_low << 25); break; } imx6_pcie_configure_type(imx6_pcie); } static int imx6_setup_phy_mpll(struct imx6_pcie *imx6_pcie) { unsigned long phy_rate = clk_get_rate(imx6_pcie->pcie_phy); int mult, div; u32 val; if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY)) return 0; switch (phy_rate) { case 125000000: /* * The default settings of the MPLL are for a 125MHz input * clock, so no need to reconfigure anything in that case. */ return 0; case 100000000: mult = 25; div = 0; break; case 200000000: mult = 25; div = 1; break; default: dev_err(imx6_pcie->pci->dev, "Unsupported PHY reference clock rate %lu\n", phy_rate); return -EINVAL; } pcie_phy_read(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, &val); val &= ~(PCIE_PHY_MPLL_MULTIPLIER_MASK << PCIE_PHY_MPLL_MULTIPLIER_SHIFT); val |= mult << PCIE_PHY_MPLL_MULTIPLIER_SHIFT; val |= PCIE_PHY_MPLL_MULTIPLIER_OVRD; pcie_phy_write(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, val); pcie_phy_read(imx6_pcie, PCIE_PHY_ATEOVRD, &val); val &= ~(PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK << PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT); val |= div << PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT; val |= PCIE_PHY_ATEOVRD_EN; pcie_phy_write(imx6_pcie, PCIE_PHY_ATEOVRD, val); return 0; } static int imx6_pcie_wait_for_link(struct imx6_pcie *imx6_pcie) { struct dw_pcie *pci = imx6_pcie->pci; struct device *dev = pci->dev; /* check if the link is up or not */ if (!dw_pcie_wait_for_link(pci)) return 0; dev_dbg(dev, "DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n", dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R0), dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R1)); return -ETIMEDOUT; } static int imx6_pcie_wait_for_speed_change(struct imx6_pcie *imx6_pcie) { struct dw_pcie *pci = imx6_pcie->pci; struct device *dev = pci->dev; u32 tmp; unsigned int retries; for (retries = 0; retries < 200; retries++) { tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL); /* Test if the speed change finished. */ if (!(tmp & PORT_LOGIC_SPEED_CHANGE)) return 0; usleep_range(100, 1000); } dev_err(dev, "Speed change timeout\n"); return -EINVAL; } static void imx6_pcie_ltssm_enable(struct device *dev) { struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); switch (imx6_pcie->drvdata->variant) { case IMX6Q: case IMX6SX: case IMX6QP: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX6Q_GPR12_PCIE_CTL_2, IMX6Q_GPR12_PCIE_CTL_2); break; case IMX7D: case IMX8MQ: reset_control_deassert(imx6_pcie->apps_reset); break; } } static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie) { struct dw_pcie *pci = imx6_pcie->pci; struct device *dev = pci->dev; u32 tmp; int ret; /* * Force Gen1 operation when starting the link. In case the link is * started in Gen2 mode, there is a possibility the devices on the * bus will not be detected at all. This happens with PCIe switches. */ tmp = dw_pcie_readl_dbi(pci, PCIE_RC_LCR); tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK; tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1; dw_pcie_writel_dbi(pci, PCIE_RC_LCR, tmp); /* Start LTSSM. */ imx6_pcie_ltssm_enable(dev); ret = imx6_pcie_wait_for_link(imx6_pcie); if (ret) goto err_reset_phy; if (imx6_pcie->link_gen == 2) { /* Allow Gen2 mode after the link is up. */ tmp = dw_pcie_readl_dbi(pci, PCIE_RC_LCR); tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK; tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2; dw_pcie_writel_dbi(pci, PCIE_RC_LCR, tmp); /* * Start Directed Speed Change so the best possible * speed both link partners support can be negotiated. */ tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL); tmp |= PORT_LOGIC_SPEED_CHANGE; dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp); if (imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE) { /* * On i.MX7, DIRECT_SPEED_CHANGE behaves differently * from i.MX6 family when no link speed transition * occurs and we go Gen1 -> yep, Gen1. The difference * is that, in such case, it will not be cleared by HW * which will cause the following code to report false * failure. */ ret = imx6_pcie_wait_for_speed_change(imx6_pcie); if (ret) { dev_err(dev, "Failed to bring link up!\n"); goto err_reset_phy; } } /* Make sure link training is finished as well! */ ret = imx6_pcie_wait_for_link(imx6_pcie); if (ret) { dev_err(dev, "Failed to bring link up!\n"); goto err_reset_phy; } } else { dev_info(dev, "Link: Gen2 disabled\n"); } tmp = dw_pcie_readl_dbi(pci, PCIE_RC_LCSR); dev_info(dev, "Link up, Gen%i\n", (tmp >> 16) & 0xf); return 0; err_reset_phy: dev_dbg(dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n", dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R0), dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R1)); imx6_pcie_reset_phy(imx6_pcie); return ret; } static int imx6_pcie_host_init(struct pcie_port *pp) { struct dw_pcie *pci = to_dw_pcie_from_pp(pp); struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci); imx6_pcie_assert_core_reset(imx6_pcie); imx6_pcie_init_phy(imx6_pcie); imx6_pcie_deassert_core_reset(imx6_pcie); imx6_setup_phy_mpll(imx6_pcie); dw_pcie_setup_rc(pp); imx6_pcie_establish_link(imx6_pcie); if (IS_ENABLED(CONFIG_PCI_MSI)) dw_pcie_msi_init(pp); return 0; } static const struct dw_pcie_host_ops imx6_pcie_host_ops = { .host_init = imx6_pcie_host_init, }; static int imx6_add_pcie_port(struct imx6_pcie *imx6_pcie, struct platform_device *pdev) { struct dw_pcie *pci = imx6_pcie->pci; struct pcie_port *pp = &pci->pp; struct device *dev = &pdev->dev; int ret; if (IS_ENABLED(CONFIG_PCI_MSI)) { pp->msi_irq = platform_get_irq_byname(pdev, "msi"); if (pp->msi_irq <= 0) { dev_err(dev, "failed to get MSI irq\n"); return -ENODEV; } } pp->ops = &imx6_pcie_host_ops; ret = dw_pcie_host_init(pp); if (ret) { dev_err(dev, "failed to initialize host\n"); return ret; } return 0; } static const struct dw_pcie_ops dw_pcie_ops = { /* No special ops needed, but pcie-designware still expects this struct */ }; #ifdef CONFIG_PM_SLEEP static void imx6_pcie_ltssm_disable(struct device *dev) { struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); switch (imx6_pcie->drvdata->variant) { case IMX6SX: case IMX6QP: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX6Q_GPR12_PCIE_CTL_2, 0); break; case IMX7D: reset_control_assert(imx6_pcie->apps_reset); break; default: dev_err(dev, "ltssm_disable not supported\n"); } } static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie) { struct device *dev = imx6_pcie->pci->dev; /* Some variants have a turnoff reset in DT */ if (imx6_pcie->turnoff_reset) { reset_control_assert(imx6_pcie->turnoff_reset); reset_control_deassert(imx6_pcie->turnoff_reset); goto pm_turnoff_sleep; } /* Others poke directly at IOMUXC registers */ switch (imx6_pcie->drvdata->variant) { case IMX6SX: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX6SX_GPR12_PCIE_PM_TURN_OFF, IMX6SX_GPR12_PCIE_PM_TURN_OFF); regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX6SX_GPR12_PCIE_PM_TURN_OFF, 0); break; default: dev_err(dev, "PME_Turn_Off not implemented\n"); return; } /* * Components with an upstream port must respond to * PME_Turn_Off with PME_TO_Ack but we can't check. * * The standard recommends a 1-10ms timeout after which to * proceed anyway as if acks were received. */ pm_turnoff_sleep: usleep_range(1000, 10000); } static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie) { clk_disable_unprepare(imx6_pcie->pcie); clk_disable_unprepare(imx6_pcie->pcie_phy); clk_disable_unprepare(imx6_pcie->pcie_bus); switch (imx6_pcie->drvdata->variant) { case IMX6SX: clk_disable_unprepare(imx6_pcie->pcie_inbound_axi); break; case IMX7D: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, IMX7D_GPR12_PCIE_PHY_REFCLK_SEL); break; case IMX8MQ: clk_disable_unprepare(imx6_pcie->pcie_aux); break; default: break; } } static inline bool imx6_pcie_supports_suspend(struct imx6_pcie *imx6_pcie) { return (imx6_pcie->drvdata->variant == IMX7D || imx6_pcie->drvdata->variant == IMX6SX); } static int imx6_pcie_suspend_noirq(struct device *dev) { struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); if (!imx6_pcie_supports_suspend(imx6_pcie)) return 0; imx6_pcie_pm_turnoff(imx6_pcie); imx6_pcie_clk_disable(imx6_pcie); imx6_pcie_ltssm_disable(dev); return 0; } static int imx6_pcie_resume_noirq(struct device *dev) { int ret; struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); struct pcie_port *pp = &imx6_pcie->pci->pp; if (!imx6_pcie_supports_suspend(imx6_pcie)) return 0; imx6_pcie_assert_core_reset(imx6_pcie); imx6_pcie_init_phy(imx6_pcie); imx6_pcie_deassert_core_reset(imx6_pcie); dw_pcie_setup_rc(pp); ret = imx6_pcie_establish_link(imx6_pcie); if (ret < 0) dev_info(dev, "pcie link is down after resume.\n"); return 0; } #endif static const struct dev_pm_ops imx6_pcie_pm_ops = { SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx6_pcie_suspend_noirq, imx6_pcie_resume_noirq) }; static int imx6_pcie_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct dw_pcie *pci; struct imx6_pcie *imx6_pcie; struct device_node *np; struct resource *dbi_base; struct device_node *node = dev->of_node; int ret; u16 val; imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL); if (!imx6_pcie) return -ENOMEM; pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL); if (!pci) return -ENOMEM; pci->dev = dev; pci->ops = &dw_pcie_ops; imx6_pcie->pci = pci; imx6_pcie->drvdata = of_device_get_match_data(dev); /* Find the PHY if one is defined, only imx7d uses it */ np = of_parse_phandle(node, "fsl,imx7d-pcie-phy", 0); if (np) { struct resource res; ret = of_address_to_resource(np, 0, &res); if (ret) { dev_err(dev, "Unable to map PCIe PHY\n"); return ret; } imx6_pcie->phy_base = devm_ioremap_resource(dev, &res); if (IS_ERR(imx6_pcie->phy_base)) { dev_err(dev, "Unable to map PCIe PHY\n"); return PTR_ERR(imx6_pcie->phy_base); } } dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0); pci->dbi_base = devm_ioremap_resource(dev, dbi_base); if (IS_ERR(pci->dbi_base)) return PTR_ERR(pci->dbi_base); /* Fetch GPIOs */ imx6_pcie->reset_gpio = of_get_named_gpio(node, "reset-gpio", 0); imx6_pcie->gpio_active_high = of_property_read_bool(node, "reset-gpio-active-high"); if (gpio_is_valid(imx6_pcie->reset_gpio)) { ret = devm_gpio_request_one(dev, imx6_pcie->reset_gpio, imx6_pcie->gpio_active_high ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW, "PCIe reset"); if (ret) { dev_err(dev, "unable to get reset gpio\n"); return ret; } } else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) { return imx6_pcie->reset_gpio; } /* Fetch clocks */ imx6_pcie->pcie_phy = devm_clk_get(dev, "pcie_phy"); if (IS_ERR(imx6_pcie->pcie_phy)) { dev_err(dev, "pcie_phy clock source missing or invalid\n"); return PTR_ERR(imx6_pcie->pcie_phy); } imx6_pcie->pcie_bus = devm_clk_get(dev, "pcie_bus"); if (IS_ERR(imx6_pcie->pcie_bus)) { dev_err(dev, "pcie_bus clock source missing or invalid\n"); return PTR_ERR(imx6_pcie->pcie_bus); } imx6_pcie->pcie = devm_clk_get(dev, "pcie"); if (IS_ERR(imx6_pcie->pcie)) { dev_err(dev, "pcie clock source missing or invalid\n"); return PTR_ERR(imx6_pcie->pcie); } switch (imx6_pcie->drvdata->variant) { case IMX6SX: imx6_pcie->pcie_inbound_axi = devm_clk_get(dev, "pcie_inbound_axi"); if (IS_ERR(imx6_pcie->pcie_inbound_axi)) { dev_err(dev, "pcie_inbound_axi clock missing or invalid\n"); return PTR_ERR(imx6_pcie->pcie_inbound_axi); } break; case IMX8MQ: imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux"); if (IS_ERR(imx6_pcie->pcie_aux)) { dev_err(dev, "pcie_aux clock source missing or invalid\n"); return PTR_ERR(imx6_pcie->pcie_aux); } /* fall through */ case IMX7D: if (dbi_base->start == IMX8MQ_PCIE2_BASE_ADDR) imx6_pcie->controller_id = 1; imx6_pcie->pciephy_reset = devm_reset_control_get_exclusive(dev, "pciephy"); if (IS_ERR(imx6_pcie->pciephy_reset)) { dev_err(dev, "Failed to get PCIEPHY reset control\n"); return PTR_ERR(imx6_pcie->pciephy_reset); } imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev, "apps"); if (IS_ERR(imx6_pcie->apps_reset)) { dev_err(dev, "Failed to get PCIE APPS reset control\n"); return PTR_ERR(imx6_pcie->apps_reset); } break; default: break; } /* Grab turnoff reset */ imx6_pcie->turnoff_reset = devm_reset_control_get_optional_exclusive(dev, "turnoff"); if (IS_ERR(imx6_pcie->turnoff_reset)) { dev_err(dev, "Failed to get TURNOFF reset control\n"); return PTR_ERR(imx6_pcie->turnoff_reset); } /* Grab GPR config register range */ imx6_pcie->iomuxc_gpr = syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr"); if (IS_ERR(imx6_pcie->iomuxc_gpr)) { dev_err(dev, "unable to find iomuxc registers\n"); return PTR_ERR(imx6_pcie->iomuxc_gpr); } /* Grab PCIe PHY Tx Settings */ if (of_property_read_u32(node, "fsl,tx-deemph-gen1", &imx6_pcie->tx_deemph_gen1)) imx6_pcie->tx_deemph_gen1 = 0; if (of_property_read_u32(node, "fsl,tx-deemph-gen2-3p5db", &imx6_pcie->tx_deemph_gen2_3p5db)) imx6_pcie->tx_deemph_gen2_3p5db = 0; if (of_property_read_u32(node, "fsl,tx-deemph-gen2-6db", &imx6_pcie->tx_deemph_gen2_6db)) imx6_pcie->tx_deemph_gen2_6db = 20; if (of_property_read_u32(node, "fsl,tx-swing-full", &imx6_pcie->tx_swing_full)) imx6_pcie->tx_swing_full = 127; if (of_property_read_u32(node, "fsl,tx-swing-low", &imx6_pcie->tx_swing_low)) imx6_pcie->tx_swing_low = 127; /* Limit link speed */ ret = of_property_read_u32(node, "fsl,max-link-speed", &imx6_pcie->link_gen); if (ret) imx6_pcie->link_gen = 1; imx6_pcie->vpcie = devm_regulator_get_optional(&pdev->dev, "vpcie"); if (IS_ERR(imx6_pcie->vpcie)) { if (PTR_ERR(imx6_pcie->vpcie) == -EPROBE_DEFER) return -EPROBE_DEFER; imx6_pcie->vpcie = NULL; } platform_set_drvdata(pdev, imx6_pcie); ret = imx6_pcie_attach_pd(dev); if (ret) return ret; ret = imx6_add_pcie_port(imx6_pcie, pdev); if (ret < 0) return ret; if (pci_msi_enabled()) { val = dw_pcie_readw_dbi(pci, PCIE_RC_IMX6_MSI_CAP + PCI_MSI_FLAGS); val |= PCI_MSI_FLAGS_ENABLE; dw_pcie_writew_dbi(pci, PCIE_RC_IMX6_MSI_CAP + PCI_MSI_FLAGS, val); } return 0; } static void imx6_pcie_shutdown(struct platform_device *pdev) { struct imx6_pcie *imx6_pcie = platform_get_drvdata(pdev); /* bring down link, so bootloader gets clean state in case of reboot */ imx6_pcie_assert_core_reset(imx6_pcie); } static const struct imx6_pcie_drvdata drvdata[] = { [IMX6Q] = { .variant = IMX6Q, .flags = IMX6_PCIE_FLAG_IMX6_PHY | IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE, }, [IMX6SX] = { .variant = IMX6SX, .flags = IMX6_PCIE_FLAG_IMX6_PHY | IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE, }, [IMX6QP] = { .variant = IMX6QP, .flags = IMX6_PCIE_FLAG_IMX6_PHY | IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE, }, [IMX7D] = { .variant = IMX7D, }, [IMX8MQ] = { .variant = IMX8MQ, }, }; static const struct of_device_id imx6_pcie_of_match[] = { { .compatible = "fsl,imx6q-pcie", .data = &drvdata[IMX6Q], }, { .compatible = "fsl,imx6sx-pcie", .data = &drvdata[IMX6SX], }, { .compatible = "fsl,imx6qp-pcie", .data = &drvdata[IMX6QP], }, { .compatible = "fsl,imx7d-pcie", .data = &drvdata[IMX7D], }, { .compatible = "fsl,imx8mq-pcie", .data = &drvdata[IMX8MQ], } , {}, }; static struct platform_driver imx6_pcie_driver = { .driver = { .name = "imx6q-pcie", .of_match_table = imx6_pcie_of_match, .suppress_bind_attrs = true, .pm = &imx6_pcie_pm_ops, }, .probe = imx6_pcie_probe, .shutdown = imx6_pcie_shutdown, }; static int __init imx6_pcie_init(void) { #ifdef CONFIG_ARM /* * Since probe() can be deferred we need to make sure that * hook_fault_code is not called after __init memory is freed * by kernel and since imx6q_pcie_abort_handler() is a no-op, * we can install the handler here without risking it * accessing some uninitialized driver state. */ hook_fault_code(8, imx6q_pcie_abort_handler, SIGBUS, 0, "external abort on non-linefetch"); #endif return platform_driver_register(&imx6_pcie_driver); } device_initcall(imx6_pcie_init);