[PATCH 9/9] PCI: imx6: Add iMX95 PCIe support

From: Frank Li
Date: Wed Dec 06 2023 - 11:00:19 EST


Add iMX95 PCIe basic root complex function support.

Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
---
drivers/pci/controller/dwc/pci-imx6.c | 85 +++++++++++++++++++++++++--
1 file changed, 80 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 990b91534ea9..7e51aef97baa 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -43,6 +43,25 @@
#define IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE GENMASK(11, 8)
#define IMX8MQ_PCIE2_BASE_ADDR 0x33c00000

+#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 {
@@ -53,6 +72,7 @@ enum imx6_pcie_variants {
IMX8MQ,
IMX8MM,
IMX8MP,
+ IMX95,
IMX8MQ_EP,
IMX8MM_EP,
IMX8MP_EP,
@@ -79,6 +99,7 @@ struct imx6_pcie_drvdata {
u32 flags;
int dbi_length;
const char *gpr;
+ u32 pf_lut_offset;
const u32 ltssm_off;
const u32 ltssm_mask;
const u32 mode_off[IMX6_PCIE_MAX_INSTANCES];
@@ -182,6 +203,24 @@ 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;
@@ -589,6 +628,7 @@ 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:
@@ -735,11 +775,20 @@ 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;

if (imx6_check_flag(imx6_pcie, IMX6_PCIE_FLAG_HAS_PHY_RESET))
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
@@ -1348,12 +1397,27 @@ 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_pcie->drvdata->pf_lut_offset) {
+ void __iomem *off = pci->dbi_base + imx6_pcie->drvdata->pf_lut_offset;
+ 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 */
@@ -1511,6 +1575,16 @@ static const struct imx6_pcie_drvdata drvdata[] = {
.mode_off[0] = IOMUXC_GPR12,
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
},
+ [IMX95] = {
+ .variant = IMX8MP,
+ .flags = IMX6_PCIE_FLAG_HAS_CLK_AUX,
+ .pf_lut_offset = 0x40000,
+ .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_CLK_AUX |
@@ -1551,6 +1625,7 @@ 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