> -----Original Message----- > From: Christoph Fritz [mailto:chf.fritz@xxxxxxxxxxxxxx] > Sent: Monday, February 15, 2016 4:53 AM > To: Lucas Stach; Richard Zhu; Bjorn Helgaas; Lee Jones > Cc: Fabio Estevam; linux-pci@xxxxxxxxxxxxxxx > Subject: [PATCH 2/2] PCI: imx6: add initial imx6sx support > > This patch adds initial PCIe support for the imx6 SoC derivate imx6sx. > PCI_MSI support is untested as its necessary suspend/resume quirk is left out of > this patch. > This patch is heavily based on patches by Richard Zhu. > > Signed-off-by: Christoph Fritz <chf.fritz@xxxxxxxxxxxxxx> > --- > drivers/pci/host/pci-imx6.c | 172 +++++++++++++++++++++++++++++++++------ > ----- > 1 file changed, 129 insertions(+), 43 deletions(-) > > diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c index > fe60096..73abc3e 100644 > --- a/drivers/pci/host/pci-imx6.c > +++ b/drivers/pci/host/pci-imx6.c > @@ -22,6 +22,7 @@ > #include <linux/pci.h> > #include <linux/platform_device.h> > #include <linux/regmap.h> > +#include <linux/regulator/consumer.h> > #include <linux/resource.h> > #include <linux/signal.h> > #include <linux/types.h> > @@ -35,9 +36,13 @@ struct imx6_pcie { > struct gpio_desc *reset_gpio; > struct clk *pcie_bus; > struct clk *pcie_phy; > + struct clk *pcie_inbound_axi; > struct clk *pcie; > struct pcie_port pp; > struct regmap *iomuxc_gpr; > + struct regmap *gpc_ips_reg; > + struct regulator *pcie_phy_regulator; > + bool is_imx6sx; > void __iomem *mem_base; > }; > > @@ -80,6 +85,9 @@ struct imx6_pcie { > #define PHY_RX_OVRD_IN_LO_RX_DATA_EN (1 << 5) #define > PHY_RX_OVRD_IN_LO_RX_PLL_EN (1 << 3) > > +#define PCIE_PHY_IMX6SX_GPC_CNTR 0x0 > +#define PCIE_PHY_IMX6SX_GPC_CNTR_PUP_REQ BIT(7) > + > static int pcie_phy_poll_ack(void __iomem *dbi_base, int exp_val) { > u32 val; > @@ -214,35 +222,46 @@ static int imx6_pcie_assert_core_reset(struct > pcie_port *pp) > struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp); > u32 val, gpr1, gpr12; > > - /* > - * If the bootloader already enabled the link we need some special > - * handling to get the core back into a state where it is safe to > - * touch it for configuration. As there is no dedicated reset signal > - * wired up for MX6QDL, we need to manually force LTSSM into > "detect" > - * state before completely disabling LTSSM, which is a prerequisite > - * for core configuration. > - * > - * If both LTSSM_ENABLE and REF_SSP_ENABLE are active we have a > strong > - * indication that the bootloader activated the link. > - */ > - regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, &gpr1); > - regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, &gpr12); > - > - if ((gpr1 & IMX6Q_GPR1_PCIE_REF_CLK_EN) && > - (gpr12 & IMX6Q_GPR12_PCIE_CTL_2)) { > - val = readl(pp->dbi_base + PCIE_PL_PFLR); > - val &= ~PCIE_PL_PFLR_LINK_STATE_MASK; > - val |= PCIE_PL_PFLR_FORCE_LINK; > - writel(val, pp->dbi_base + PCIE_PL_PFLR); > - > + if (imx6_pcie->is_imx6sx) { > regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, > - IMX6Q_GPR12_PCIE_CTL_2, 0 << 10); > - } > + > IMX6SX_GPR12_PCIE_TEST_POWERDOWN_MASK, > + > IMX6SX_GPR12_PCIE_TEST_POWERDOWN_ENABLE); > + /* Force PCIe PHY reset */ > + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5, > + IMX6SX_GPR5_PCIE_BTNRST_MASK, > + IMX6SX_GPR5_PCIE_BTNRST_RESET); > + } else { > + /* > + * If the bootloader already enabled the link we need some > + * special handling to get the core back into a state where > + * it is safe to touch it for configuration. As there is no > + * dedicated reset signal to manually force LTSSM into "detect" > + * state before completely disabling LTSSM, which is a > + * prerequisite for core configuration. > + * > + * If both LTSSM_ENABLE and REF_SSP_ENABLE are active we > have > + * a strong indication that the bootloader activated the link. > + */ > + regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, &gpr1); > + regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, > &gpr12); > + > + if ((gpr1 & IMX6Q_GPR1_PCIE_REF_CLK_EN) && > + (gpr12 & IMX6Q_GPR12_PCIE_CTL_2)) { > + val = readl(pp->dbi_base + PCIE_PL_PFLR); > + val &= ~PCIE_PL_PFLR_LINK_STATE_MASK; > + val |= PCIE_PL_PFLR_FORCE_LINK; > + writel(val, pp->dbi_base + PCIE_PL_PFLR); > + > + regmap_update_bits(imx6_pcie->iomuxc_gpr, > IOMUXC_GPR12, > + IMX6Q_GPR12_PCIE_CTL_2, 0); > + } > > - 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); > + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, > + IMX6Q_GPR1_PCIE_TEST_PD, > + IMX6Q_GPR1_PCIE_TEST_PD); > + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, > + IMX6Q_GPR1_PCIE_REF_CLK_EN, 0); > + } > > return 0; > } > @@ -270,18 +289,31 @@ static int imx6_pcie_deassert_core_reset(struct > pcie_port *pp) > goto err_pcie; > } > > - /* 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); > + if (imx6_pcie->is_imx6sx) { > + ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi); > + if (ret) { > + dev_err(pp->dev, "unable to enable pcie_axi clock\n"); > + goto err_inbound_axi; > + } > + > + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, > + IMX6SX_GPR12_PCIE_TEST_POWERDOWN_MASK, > + IMX6SX_GPR12_PCIE_TEST_POWERDOWN_DISABLE); > + } else { > + /* power up core phy and enable ref clock */ > + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, > + IMX6Q_GPR1_PCIE_TEST_PD, 0); > + /* > + * 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, > + IMX6Q_GPR1_PCIE_REF_CLK_EN); > + } > > /* allow the clocks to stabilize */ > usleep_range(200, 500); > @@ -292,8 +324,16 @@ static int imx6_pcie_deassert_core_reset(struct > pcie_port *pp) > msleep(100); > gpiod_set_value_cansleep(imx6_pcie->reset_gpio, 1); > } > + > + if (imx6_pcie->is_imx6sx) > + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5, > + IMX6SX_GPR5_PCIE_BTNRST_MASK, > + IMX6SX_GPR5_PCIE_BTNRST_RELEASE); > + > return 0; > > +err_inbound_axi: > + clk_disable_unprepare(imx6_pcie->pcie); > err_pcie: > clk_disable_unprepare(imx6_pcie->pcie_bus); > err_pcie_bus: > @@ -303,9 +343,28 @@ err_pcie_phy: > > } > > -static void imx6_pcie_init_phy(struct pcie_port *pp) > +static int imx6_pcie_init_phy(struct pcie_port *pp) > { > struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp); > + int ret = 0; > + > + if (imx6_pcie->is_imx6sx) { > + /* power up separate domain available on i.mx6sx */ > + regmap_update_bits(imx6_pcie->gpc_ips_reg, > + PCIE_PHY_IMX6SX_GPC_CNTR, > + PCIE_PHY_IMX6SX_GPC_CNTR_PUP_REQ, > + PCIE_PHY_IMX6SX_GPC_CNTR_PUP_REQ); [Zhu hongxing] First of all, thanks for trying to upstream imx6sx pcie driver. As Lucas discussed with me before, the GPC regulator operations should be touched in Imx pcie driver at all. These bits operations should be encapsulate into the PM system, for example, the regulator driver. > + regulator_set_voltage(imx6_pcie->pcie_phy_regulator, > + 1100000, 1100000); > + ret = regulator_enable(imx6_pcie->pcie_phy_regulator); > + if (ret) { > + dev_err(pp->dev, "cannot enable pcie_phy > regulator\n"); > + return ret; > + } > + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, > + IMX6SX_GPR12_PCIE_RX_EQ_MASK, > + IMX6SX_GPR12_PCIE_RX_EQ_2); > + } > > regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, > IMX6Q_GPR12_PCIE_CTL_2, 0 << 10); > @@ -326,6 +385,8 @@ static void imx6_pcie_init_phy(struct pcie_port *pp) > IMX6Q_GPR8_TX_SWING_FULL, 127 << 18); > regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, > IMX6Q_GPR8_TX_SWING_LOW, 127 << 25); > + > + return ret; > } > > static int imx6_pcie_wait_for_link(struct pcie_port *pp) @@ -571,6 +632,9 > @@ static int __init imx6_pcie_probe(struct platform_device *pdev) > pp = &imx6_pcie->pp; > pp->dev = &pdev->dev; > > + imx6_pcie->is_imx6sx = of_device_is_compatible(pp->dev->of_node, > + "fsl,imx6sx-pcie"); > + > /* Added for PCI abort handling */ > hook_fault_code(16 + 6, imx6q_pcie_abort_handler, SIGBUS, 0, > "imprecise external abort"); > @@ -606,9 +670,30 @@ static int __init imx6_pcie_probe(struct > platform_device *pdev) > return PTR_ERR(imx6_pcie->pcie); > } > > - /* Grab GPR config register range */ > - imx6_pcie->iomuxc_gpr = > - syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc- > gpr"); > + if (imx6_pcie->is_imx6sx) { > + imx6_pcie->pcie_inbound_axi = devm_clk_get(&pdev->dev, > + "pcie_inbound_axi"); > + > + if (IS_ERR(imx6_pcie->pcie_inbound_axi)) { > + dev_err(&pdev->dev, > + "pcie_incbound_axi clock missing or invalid\n"); > + return PTR_ERR(imx6_pcie->pcie_inbound_axi); > + } > + > + imx6_pcie->pcie_phy_regulator = devm_regulator_get(pp- > >dev, > + "pcie-phy"); > + > + imx6_pcie->iomuxc_gpr = > + syscon_regmap_lookup_by_compatible > + ("fsl,imx6sx-iomuxc-gpr"); > + > + imx6_pcie->gpc_ips_reg = > + syscon_regmap_lookup_by_compatible("fsl,imx6sx- > gpc"); > + } else { > + imx6_pcie->iomuxc_gpr = > + syscon_regmap_lookup_by_compatible > + ("fsl,imx6q-iomuxc-gpr"); > + } > if (IS_ERR(imx6_pcie->iomuxc_gpr)) { > dev_err(&pdev->dev, "unable to find iomuxc registers\n"); > return PTR_ERR(imx6_pcie->iomuxc_gpr); @@ -632,6 +717,7 > @@ static void imx6_pcie_shutdown(struct platform_device *pdev) > > static const struct of_device_id imx6_pcie_of_match[] = { > { .compatible = "fsl,imx6q-pcie", }, > + { .compatible = "fsl,imx6sx-pcie", }, > {}, > }; > MODULE_DEVICE_TABLE(of, imx6_pcie_of_match); > -- > 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
