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When these are > managed together, the timing between PHY power-up and reference clock > enablement cannot be properly controlled, leading to initialization > failures. > > Fix this by separating the two concerns: > > - Move PHY power control (TEST_PD) to imx6q_pcie_core_reset() where it > logically belongs with reset operations. This ensures PHY power state > is managed as part of the core reset sequence. > > - Update imx6qp_pcie_core_reset() to call imx6q_pcie_core_reset() for > shared PHY power management, avoiding code duplication. > > - Make imx6q_pcie_enable_ref_clk() responsible only for reference clock > (REF_CLK_EN) control, simplifying its purpose. > > - Remove the 10us delay workaround from imx6q_pcie_enable_ref_clk() as > proper sequencing is now handled by the core_reset functions. > > This refactoring ensures PHY power is controlled during reset > operations, fixing the boot hang while improving code maintainability. > > Fixes: 610fa91d9863 ("PCI: imx6: Assert PERST# before enabling regulators") > Signed-off-by: Richard Zhu > --- look more symmetry than before. Reviewed-by: Frank Li > Changes in v2: > Regarding sashiko's reivew, invoke imx_pcie_assert_core_reset() explicitly > in error path of imx_pcie_host_init() and imx_pcie_host_exit(). > --- > drivers/pci/controller/dwc/pci-imx6.c | 45 ++++++++++++--------------- > 1 file changed, 20 insertions(+), 25 deletions(-) > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c > index 9406bba36953f..53f3da6ab30d5 100644 > --- a/drivers/pci/controller/dwc/pci-imx6.c > +++ b/drivers/pci/controller/dwc/pci-imx6.c > @@ -680,21 +680,12 @@ static int imx_pcie_attach_pd(struct device *dev) > > static int imx6q_pcie_enable_ref_clk(struct imx_pcie *imx_pcie, bool enable) > { > - if (enable) { > - /* power up core phy and enable ref clock */ > - regmap_clear_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_TEST_PD); > - /* > - * 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 a ~10us delay here. > - */ > - usleep_range(10, 100); > - regmap_set_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_REF_CLK_EN); > - } else { > - regmap_clear_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_REF_CLK_EN); > - regmap_set_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_TEST_PD); > - } > + if (enable) > + regmap_set_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, > + IMX6Q_GPR1_PCIE_REF_CLK_EN); > + else > + regmap_clear_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, > + IMX6Q_GPR1_PCIE_REF_CLK_EN); > > return 0; > } > @@ -823,23 +814,25 @@ static int imx6sx_pcie_core_reset(struct imx_pcie *imx_pcie, bool assert) > return 0; > } > > -static int imx6qp_pcie_core_reset(struct imx_pcie *imx_pcie, bool assert) > +static int imx6q_pcie_core_reset(struct imx_pcie *imx_pcie, bool assert) > { > - regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_SW_RST, > - assert ? IMX6Q_GPR1_PCIE_SW_RST : 0); > - if (!assert) > - usleep_range(200, 500); > + if (assert) > + regmap_set_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, > + IMX6Q_GPR1_PCIE_TEST_PD); > + else > + regmap_clear_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, > + IMX6Q_GPR1_PCIE_TEST_PD); > > return 0; > } > > -static int imx6q_pcie_core_reset(struct imx_pcie *imx_pcie, bool assert) > +static int imx6qp_pcie_core_reset(struct imx_pcie *imx_pcie, bool assert) > { > + imx6q_pcie_core_reset(imx_pcie, assert); > + regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_SW_RST, > + assert ? IMX6Q_GPR1_PCIE_SW_RST : 0); > if (!assert) > - return 0; > - > - regmap_set_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_TEST_PD); > - regmap_set_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_REF_CLK_EN); > + usleep_range(200, 500); > > return 0; > } > @@ -1445,6 +1438,7 @@ static int imx_pcie_host_init(struct dw_pcie_rp *pp) > return 0; > > err_phy_off: > + imx_pcie_assert_core_reset(imx_pcie); > phy_power_off(imx_pcie->phy); > err_phy_exit: > phy_exit(imx_pcie->phy); > @@ -1471,6 +1465,7 @@ static void imx_pcie_host_exit(struct dw_pcie_rp *pp) > dev_err(pci->dev, "unable to power off PHY\n"); > phy_exit(imx_pcie->phy); > } > + imx_pcie_assert_core_reset(imx_pcie); > imx_pcie_clk_disable(imx_pcie); > > pci_pwrctrl_power_off_devices(pci->dev); > -- > 2.34.1 > >