[PATCH v7 12/16] PCI: imx6: Add iMX95 PCIe support

From: Frank Li <Frank.Li@nxp.com>
To: krzysztof.kozlowski@linaro.org
Cc: Frank.Li@nxp.com, bhelgaas@google.com, conor+dt@kernel.org,
	devicetree@vger.kernel.org, festevam@gmail.com,
	helgaas@kernel.org, hongxing.zhu@nxp.com, imx@lists.linux.dev,
	kernel@pengutronix.de, krzysztof.kozlowski+dt@linaro.org,
	kw@linux.com, l.stach@pengutronix.de,
	linux-arm-kernel@lists.infradead.org, linux-imx@nxp.com,
	linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org,
	lpieralisi@kernel.org, manivannan.sadhasivam@linaro.org,
	robh@kernel.org, s.hauer@pengutronix.de, shawnguo@kernel.org
Subject: [PATCH v7 12/16] PCI: imx6: Add iMX95 PCIe support
Date: Wed, 27 Dec 2023 13:27:23 -0500	[thread overview]
Message-ID: <20231227182727.1747435-13-Frank.Li@nxp.com> (raw)
In-Reply-To: <20231227182727.1747435-1-Frank.Li@nxp.com>

Add iMX95 PCIe basic root complex function support.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---

Notes:
    Change from v1 to v3
    - none

 drivers/pci/controller/dwc/pci-imx6.c | 90 +++++++++++++++++++++++++--
 1 file changed, 85 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index d66a2db53bdb7..9e60ab6f1885a 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -42,6 +42,25 @@
 #define IMX8MQ_GPR_PCIE_VREG_BYPASS		BIT(12)
 #define IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE	GENMASK(11, 8)
 
+#define IMX95_PCIE_PHY_GEN_CTRL			0x0
+#define IMX95_PCIE_REF_USE_PAD			BIT(17)
+
+#define IMX95_PCIE_PHY_MPLLA_CTRL		0x10
+#define IMX95_PCIE_PHY_MPLL_STATE		BIT(30)
+
+#define IMX95_PCIE_SS_RW_REG_0			0xf0
+#define IMX95_PCIE_REF_CLKEN			BIT(23)
+#define IMX95_PCIE_PHY_CR_PARA_SEL		BIT(9)
+
+#define IMX95_PE0_GEN_CTRL_1			0x1050
+#define IMX95_PCIE_DEVICE_TYPE			GENMASK(3, 0)
+
+#define IMX95_PE0_GEN_CTRL_3			0x1058
+#define IMX95_PCIE_LTSSM_EN			BIT(0)
+
+#define IMX95_PE0_PM_STS			0x1064
+#define IMX95_PCIE_PM_LINKST_IN_L2		BIT(14)
+
 #define to_imx6_pcie(x)	dev_get_drvdata((x)->dev)
 
 enum imx6_pcie_variants {
@@ -52,6 +71,7 @@ enum imx6_pcie_variants {
 	IMX8MQ,
 	IMX8MM,
 	IMX8MP,
+	IMX95,
 	IMX8MQ_EP,
 	IMX8MM_EP,
 	IMX8MP_EP,
@@ -63,6 +83,7 @@ enum imx6_pcie_variants {
 #define IMX6_PCIE_FLAG_HAS_PHY			BIT(3)
 #define IMX6_PCIE_FLAG_HAS_APP_RESET		BIT(4)
 #define IMX6_PCIE_FLAG_HAS_PHY_RESET		BIT(5)
+#define IMX6_PCIE_FLAG_HAS_SERDES		BIT(6)
 
 #define imx6_check_flag(pci, val)     (pci->drvdata->flags & val)
 
@@ -179,6 +200,24 @@ static unsigned int imx6_pcie_grp_offset(const struct imx6_pcie *imx6_pcie)
 	return imx6_pcie->controller_id == 1 ? IOMUXC_GPR16 : IOMUXC_GPR14;
 }
 
+static int imx95_pcie_init_phy(struct imx6_pcie *imx6_pcie)
+{
+	regmap_update_bits(imx6_pcie->iomuxc_gpr,
+			IMX95_PCIE_SS_RW_REG_0,
+			IMX95_PCIE_PHY_CR_PARA_SEL,
+			IMX95_PCIE_PHY_CR_PARA_SEL);
+
+	regmap_update_bits(imx6_pcie->iomuxc_gpr,
+			   IMX95_PCIE_PHY_GEN_CTRL,
+			   IMX95_PCIE_REF_USE_PAD, 0);
+	regmap_update_bits(imx6_pcie->iomuxc_gpr,
+			   IMX95_PCIE_SS_RW_REG_0,
+			   IMX95_PCIE_REF_CLKEN,
+			   IMX95_PCIE_REF_CLKEN);
+
+	return 0;
+}
+
 static void imx6_pcie_configure_type(struct imx6_pcie *imx6_pcie)
 {
 	const struct imx6_pcie_drvdata *drvdata = imx6_pcie->drvdata;
@@ -579,6 +618,7 @@ static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
 				   IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
 		break;
 	case IMX7D:
+	case IMX95:
 		break;
 	case IMX8MM:
 	case IMX8MM_EP:
@@ -696,10 +736,19 @@ static int imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
 {
 	struct dw_pcie *pci = imx6_pcie->pci;
 	struct device *dev = pci->dev;
+	u32 val;
 
 	reset_control_deassert(imx6_pcie->pciephy_reset);
 
 	switch (imx6_pcie->drvdata->variant) {
+	case IMX95:
+		/* Polling the MPLL_STATE */
+		if (regmap_read_poll_timeout(imx6_pcie->iomuxc_gpr,
+					IMX95_PCIE_PHY_MPLLA_CTRL, val,
+					val & IMX95_PCIE_PHY_MPLL_STATE,
+					10, 10000))
+			dev_err(dev, "PCIe PLL lock timeout\n");
+		break;
 	case IMX7D:
 		/* Workaround for ERR010728, failure of PCI-e PLL VCO to
 		 * oscillate, especially when cold.  This turns off "Duty-cycle
@@ -1281,12 +1330,32 @@ static int imx6_pcie_probe(struct platform_device *pdev)
 		return PTR_ERR(imx6_pcie->turnoff_reset);
 	}
 
+	if (imx6_pcie->drvdata->gpr) {
 	/* Grab GPR config register range */
-	imx6_pcie->iomuxc_gpr =
-		 syscon_regmap_lookup_by_compatible(imx6_pcie->drvdata->gpr);
-	if (IS_ERR(imx6_pcie->iomuxc_gpr)) {
-		dev_err(dev, "unable to find iomuxc registers\n");
-		return PTR_ERR(imx6_pcie->iomuxc_gpr);
+		imx6_pcie->iomuxc_gpr =
+			 syscon_regmap_lookup_by_compatible(imx6_pcie->drvdata->gpr);
+		if (IS_ERR(imx6_pcie->iomuxc_gpr))
+			return dev_err_probe(dev, PTR_ERR(imx6_pcie->iomuxc_gpr),
+					     "unable to find iomuxc registers\n");
+	}
+
+	if (imx6_check_flag(imx6_pcie, IMX6_PCIE_FLAG_HAS_SERDES)) {
+		void __iomem *off = devm_platform_ioremap_resource_byname(pdev, "app");
+
+		if (IS_ERR(off))
+			return dev_err_probe(dev, PTR_ERR(off),
+					     "unable to find serdes registers\n");
+
+		static struct regmap_config regmap_config = {
+			.reg_bits = 32,
+			.val_bits = 32,
+			.reg_stride = 4,
+		};
+
+		imx6_pcie->iomuxc_gpr = devm_regmap_init_mmio(dev, off, &regmap_config);
+		if (IS_ERR(imx6_pcie->iomuxc_gpr))
+			return dev_err_probe(dev, PTR_ERR(imx6_pcie->iomuxc_gpr),
+					     "unable to find iomuxc registers\n");
 	}
 
 	/* Grab PCIe PHY Tx Settings */
@@ -1447,6 +1516,16 @@ static const struct imx6_pcie_drvdata drvdata[] = {
 		.mode_off[0] = IOMUXC_GPR12,
 		.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
 	},
+	[IMX95] = {
+		.variant = IMX95,
+		.flags = IMX6_PCIE_FLAG_HAS_SERDES,
+		.clk_names = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux"},
+		.ltssm_off = IMX95_PE0_GEN_CTRL_3,
+		.ltssm_mask = IMX95_PCIE_LTSSM_EN,
+		.mode_off[0]  = IMX95_PE0_GEN_CTRL_1,
+		.mode_mask[0] = IMX95_PCIE_DEVICE_TYPE,
+		.init_phy = imx95_pcie_init_phy,
+	},
 	[IMX8MQ_EP] = {
 		.variant = IMX8MQ_EP,
 		.flags = IMX6_PCIE_FLAG_HAS_APP_RESET |
@@ -1488,6 +1567,7 @@ static const struct of_device_id imx6_pcie_of_match[] = {
 	{ .compatible = "fsl,imx8mq-pcie", .data = &drvdata[IMX8MQ], },
 	{ .compatible = "fsl,imx8mm-pcie", .data = &drvdata[IMX8MM], },
 	{ .compatible = "fsl,imx8mp-pcie", .data = &drvdata[IMX8MP], },
+	{ .compatible = "fsl,imx95-pcie", .data = &drvdata[IMX95], },
 	{ .compatible = "fsl,imx8mq-pcie-ep", .data = &drvdata[IMX8MQ_EP], },
 	{ .compatible = "fsl,imx8mm-pcie-ep", .data = &drvdata[IMX8MM_EP], },
 	{ .compatible = "fsl,imx8mp-pcie-ep", .data = &drvdata[IMX8MP_EP], },
-- 
2.34.1

