[PATCH 5/6] PCI: imx: Simplify switch-case logic by involve core_reset callback

[Frank Li <Frank.Li@nxp.com>]

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-imx.c | 131 ++++++++++++++++++-----------------
 1 file changed, 68 insertions(+), 63 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-imx.c b/drivers/pci/controller/dwc/pci-imx.c
index a63ce171ede8f..460d40115935b 100644
--- a/drivers/pci/controller/dwc/pci-imx.c
+++ b/drivers/pci/controller/dwc/pci-imx.c
@@ -104,6 +104,7 @@ 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 {
@@ -671,35 +672,72 @@ 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)
+{
+	regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX6SX_GPR12_PCIE_TEST_POWERDOWN,
+			   assert ? IMX6SX_GPR12_PCIE_TEST_POWERDOWN : 0);
+	/* 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)
+{
+	regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_TEST_PD,
+			   assert ? IMX6Q_GPR1_PCIE_TEST_PD : 0);
+
+	regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_REF_CLK_EN,
+			   assert ? 0 : 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. */
 	if (gpio_is_valid(imx_pcie->reset_gpio))
@@ -709,47 +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 (gpio_is_valid(imx_pcie->reset_gpio)) {
@@ -1444,6 +1445,7 @@ 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,
@@ -1459,6 +1461,7 @@ 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,
@@ -1475,6 +1478,7 @@ 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,
@@ -1488,6 +1492,7 @@ 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