[PATCH v7 10/10] PCI: imx6: Add i.MX8Q PCIe root complex (RC) support

From: Frank Li
Date: Mon Jul 08 2024 - 13:12:46 EST


From: Richard Zhu <hongxing.zhu@xxxxxxx>

Implement i.MX8Q (i.MX8QM, i.MX8QXP, and i.MX8DXL) PCIe RC support. While
the controller resembles that of iMX8MP, the PHY differs significantly.
Notably, there's a distinction between PCI bus addresses and CPU addresses.

Introduce IMX_PCIE_FLAG_CPU_ADDR_FIXUP in drvdata::flags to indicate driver
need the cpu_addr_fixup() callback to facilitate CPU address to PCI bus
address conversion according to "ranges" property.

Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
---
drivers/pci/controller/dwc/pci-imx6.c | 35 +++++++++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index c72c7a0b0e02d..4e029d1c284e8 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -66,6 +66,7 @@ enum imx_pcie_variants {
IMX8MQ,
IMX8MM,
IMX8MP,
+ IMX8Q,
IMX95,
IMX8MQ_EP,
IMX8MM_EP,
@@ -81,6 +82,7 @@ enum imx_pcie_variants {
#define IMX_PCIE_FLAG_HAS_PHY_RESET BIT(5)
#define IMX_PCIE_FLAG_HAS_SERDES BIT(6)
#define IMX_PCIE_FLAG_SUPPORT_64BIT BIT(7)
+#define IMX_PCIE_FLAG_CPU_ADDR_FIXUP BIT(8)

#define imx_check_flag(pci, val) (pci->drvdata->flags & val)

@@ -1015,6 +1017,22 @@ static void imx_pcie_host_exit(struct dw_pcie_rp *pp)
regulator_disable(imx_pcie->vpcie);
}

+static u64 imx_pcie_cpu_addr_fixup(struct dw_pcie *pcie, u64 cpu_addr)
+{
+ struct imx_pcie *imx_pcie = to_imx_pcie(pcie);
+ struct dw_pcie_rp *pp = &pcie->pp;
+ struct resource_entry *entry;
+ unsigned int offset;
+
+ if (!(imx_pcie->drvdata->flags & IMX_PCIE_FLAG_CPU_ADDR_FIXUP))
+ return cpu_addr;
+
+ entry = resource_list_first_type(&pp->bridge->windows, IORESOURCE_MEM);
+ offset = entry->offset;
+
+ return (cpu_addr - offset);
+}
+
static const struct dw_pcie_host_ops imx_pcie_host_ops = {
.init = imx_pcie_host_init,
.deinit = imx_pcie_host_exit,
@@ -1023,6 +1041,7 @@ static const struct dw_pcie_host_ops imx_pcie_host_ops = {
static const struct dw_pcie_ops dw_pcie_ops = {
.start_link = imx_pcie_start_link,
.stop_link = imx_pcie_stop_link,
+ .cpu_addr_fixup = imx_pcie_cpu_addr_fixup,
};

static void imx_pcie_ep_init(struct dw_pcie_ep *ep)
@@ -1452,6 +1471,13 @@ static int imx_pcie_probe(struct platform_device *pdev)
if (ret < 0)
return ret;

+ if (imx_check_flag(imx_pcie, IMX_PCIE_FLAG_CPU_ADDR_FIXUP)) {
+ if (!resource_list_first_type(&pci->pp.bridge->windows, IORESOURCE_MEM)) {
+ dw_pcie_host_deinit(&pci->pp);
+ return dev_err_probe(dev, -ENODEV, "DTS Miss PCI memory range");
+ }
+ }
+
if (pci_msi_enabled()) {
u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);

@@ -1476,6 +1502,7 @@ static const char * const imx6q_clks[] = {"pcie_bus", "pcie", "pcie_phy"};
static const char * const imx8mm_clks[] = {"pcie_bus", "pcie", "pcie_aux"};
static const char * const imx8mq_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux"};
static const char * const imx6sx_clks[] = {"pcie_bus", "pcie", "pcie_phy", "pcie_inbound_axi"};
+static const char * const imx8q_clks[] = {"mstr", "slv", "dbi"};

static const struct imx_pcie_drvdata drvdata[] = {
[IMX6Q] = {
@@ -1579,6 +1606,13 @@ static const struct imx_pcie_drvdata drvdata[] = {
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
.enable_ref_clk = imx8mm_pcie_enable_ref_clk,
},
+ [IMX8Q] = {
+ .variant = IMX8Q,
+ .flags = IMX_PCIE_FLAG_HAS_PHYDRV |
+ IMX_PCIE_FLAG_CPU_ADDR_FIXUP,
+ .clk_names = imx8q_clks,
+ .clks_cnt = ARRAY_SIZE(imx8q_clks),
+ },
[IMX95] = {
.variant = IMX95,
.flags = IMX_PCIE_FLAG_HAS_SERDES,
@@ -1656,6 +1690,7 @@ static const struct of_device_id imx_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,imx8q-pcie", .data = &drvdata[IMX8Q], },
{ .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], },

--
2.34.1