[PATCH v5 05/12] PCI: imx6: Simplify switch-case logic by involve core_reset callback

Frank Li
2024-05-28T19:39:58Z

Instead of using the switch case statement to assert/dassert the core reset
handled by this driver itself, let's introduce a new callback core_reset()
and define it for platforms that require it. This simplifies the code.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
drivers/pci/controller/dwc/pci-imx6.c | 134 ++++++++++++++++++----------------
1 file changed, 71 insertions(+), 63 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index c5d490afa981e..5e21fc942e90e 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -103,6 +103,7 @@ struct imx_pcie_drvdata {
const struct pci_epc_features *epc_features;
int (*init_phy)(struct imx_pcie *pcie);
int (*set_ref_clk)(struct imx_pcie *pcie, bool enable);
+ int (*core_reset)(struct imx_pcie *pcie, bool assert);
};

struct imx_pcie {
@@ -670,35 +671,75 @@ static void imx_pcie_clk_disable(struct imx_pcie *imx_pcie)
clk_bulk_disable_unprepare(imx_pcie->drvdata->clks_cnt, imx_pcie->clks);
}

+static int imx6sx_pcie_core_reset(struct imx_pcie *imx_pcie, bool assert)
+{
+ if (assert)
+ regmap_set_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6SX_GPR12_PCIE_TEST_POWERDOWN);
+
+ /* Force PCIe PHY reset */
+ regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR5, IMX6SX_GPR5_PCIE_BTNRST_RESET,
+ assert ? IMX6SX_GPR5_PCIE_BTNRST_RESET : 0);
+ return 0;
+}
+
+static int imx6qp_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);
+
+ return 0;
+}
+
+static int imx6q_pcie_core_reset(struct imx_pcie *imx_pcie, bool assert)
+{
+ 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);
+
+ return 0;
+}
+
+static int imx7d_pcie_core_reset(struct imx_pcie *imx_pcie, bool assert)
+{
+ struct dw_pcie *pci = imx_pcie->pci;
+ struct device *dev = pci->dev;
+
+ if (assert)
+ return 0;
+
+ /*
+ * 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(imx_pcie->phy_base)) {
+ /* De-assert DCC_FB_EN */
+ writel(PCIE_PHY_CMN_REG4_DCC_FB_EN, imx_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,
+ imx_pcie->phy_base + PCIE_PHY_CMN_REG24);
+ /* Assert ATT_MODE */
+ writel(PCIE_PHY_CMN_REG26_ATT_MODE, imx_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(imx_pcie);
+ return 0;
+}
+
static void imx_pcie_assert_core_reset(struct imx_pcie *imx_pcie)
{
reset_control_assert(imx_pcie->pciephy_reset);
reset_control_assert(imx_pcie->apps_reset);

- switch (imx_pcie->drvdata->variant) {
- case IMX6SX:
- regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR12,
- IMX6SX_GPR12_PCIE_TEST_POWERDOWN,
- IMX6SX_GPR12_PCIE_TEST_POWERDOWN);
- /* Force PCIe PHY reset */
- regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR5,
- IMX6SX_GPR5_PCIE_BTNRST_RESET,
- IMX6SX_GPR5_PCIE_BTNRST_RESET);
- break;
- case IMX6QP:
- regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1,
- IMX6Q_GPR1_PCIE_SW_RST,
- IMX6Q_GPR1_PCIE_SW_RST);
- break;
- case IMX6Q:
- regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1,
- IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18);
- regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1,
- IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16);
- break;
- default:
- break;
- }
+ if (imx_pcie->drvdata->core_reset)
+ imx_pcie->drvdata->core_reset(imx_pcie, true);

/* Some boards don't have PCIe reset GPIO. */
gpiod_set_value_cansleep(imx_pcie->reset_gpiod, 1);
@@ -706,47 +747,10 @@ static void imx_pcie_assert_core_reset(struct imx_pcie *imx_pcie)

static int imx_pcie_deassert_core_reset(struct imx_pcie *imx_pcie)
{
- struct dw_pcie *pci = imx_pcie->pci;
- struct device *dev = pci->dev;
-
reset_control_deassert(imx_pcie->pciephy_reset);

- switch (imx_pcie->drvdata->variant) {
- case IMX7D:
- /* 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(imx_pcie->phy_base)) {
- /* De-assert DCC_FB_EN */
- writel(PCIE_PHY_CMN_REG4_DCC_FB_EN,
- imx_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,
- imx_pcie->phy_base + PCIE_PHY_CMN_REG24);
- /* Assert ATT_MODE */
- writel(PCIE_PHY_CMN_REG26_ATT_MODE,
- imx_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(imx_pcie);
- break;
- case IMX6SX:
- regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR5,
- IMX6SX_GPR5_PCIE_BTNRST_RESET, 0);
- break;
- case IMX6QP:
- regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1,
- IMX6Q_GPR1_PCIE_SW_RST, 0);
-
- usleep_range(200, 500);
- break;
- default:
- break;
- }
+ if (imx_pcie->drvdata->core_reset)
+ imx_pcie->drvdata->core_reset(imx_pcie, false);

/* Some boards don't have PCIe reset GPIO. */
if (imx_pcie->reset_gpiod) {
@@ -1442,6 +1446,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
.init_phy = imx_pcie_init_phy,
.set_ref_clk = imx6q_pcie_set_ref_clk,
+ .core_reset = imx6q_pcie_core_reset,
},
[IMX6SX] = {
.variant = IMX6SX,
@@ -1457,6 +1462,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
.init_phy = imx6sx_pcie_init_phy,
.set_ref_clk = imx6sx_pcie_set_ref_clk,
+ .core_reset = imx6sx_pcie_core_reset,
},
[IMX6QP] = {
.variant = IMX6QP,
@@ -1473,6 +1479,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
.init_phy = imx_pcie_init_phy,
.set_ref_clk = imx6q_pcie_set_ref_clk,
+ .core_reset = imx6qp_pcie_core_reset,
},
[IMX7D] = {
.variant = IMX7D,
@@ -1486,6 +1493,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
.init_phy = imx7d_pcie_init_phy,
.set_ref_clk = imx7d_pcie_set_ref_clk,
+ .core_reset = imx7d_pcie_core_reset,
},
[IMX8MQ] = {
.variant = IMX8MQ,

--
2.34.1