Add initial PCIe support for the imx6 SoC derivate imx6sx. PCI MSI support
is untested as the necessary suspend/resume quirk is not included in this
patch.
This patch is heavily based on patches by Richard Zhu.
[bhelgaas: factor out refclk enable, fix adjacent typos in imx6q-pcie.txt]
Signed-off-by: Christoph Fritz <chf.fritz@xxxxxxxxxxxxxx>
Acked-by: Richard Zhu <Richard.Zhu@xxxxxxxxxxxxx>
Acked-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
---
.../devicetree/bindings/pci/fsl,imx6q-pcie.txt | 8 +++-
drivers/pci/host/pci-imx6.c | 53 ++++++++++++++++++++++
2 files changed, 59 insertions(+), 2 deletions(-)
diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
index 6fbba53..6ee4439 100644
--- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
+++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
@@ -4,8 +4,8 @@ This PCIe host controller is based on the Synopsis Designware PCIe IP
and thus inherits all the common properties defined in designware-pcie.txt.
Required properties:
-- compatible: "fsl,imx6q-pcie"
-- reg: base addresse and length of the pcie controller
+- compatible: "fsl,imx6q-pcie", "fsl,imx6sx-pcie"
+- reg: base address and length of the PCIe controller
- interrupts: A list of interrupt outputs of the controller. Must contain an
entry for each entry in the interrupt-names property.
- interrupt-names: Must include the following entries:
@@ -13,6 +13,10 @@ Required properties:
- clock-names: Must include the following additional entries:
- "pcie_phy"
+Additional required properties for imx6sx-pcie:
+- clock names: Must include the following additional entries:
+ - "pcie_inbound_axi"
+
Example:
pcie@0x01000000 {
diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
index 4e0e47f..fa3a544 100644
--- a/drivers/pci/host/pci-imx6.c
+++ b/drivers/pci/host/pci-imx6.c
@@ -35,9 +35,11 @@ struct imx6_pcie {
struct gpio_desc *reset_gpio;
struct clk *pcie_bus;
struct clk *pcie_phy;
+ struct clk *pcie_inbound_axi;
struct clk *pcie;
struct pcie_port pp;
struct regmap *iomuxc_gpr;
+ bool is_imx6sx;
void __iomem *mem_base;
};
@@ -231,6 +233,17 @@ static int imx6_pcie_assert_core_reset(struct pcie_port *pp)
struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
u32 val, gpr1, gpr12;
+ if (imx6_pcie->is_imx6sx) {
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6SX_GPR12_PCIE_TEST_POWERDOWN,
+ IMX6SX_GPR12_PCIE_TEST_POWERDOWN);
+ /* Force PCIe PHY reset */
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
+ IMX6SX_GPR5_PCIE_BTNRST_RESET,
+ IMX6SX_GPR5_PCIE_BTNRST_RESET);
+ return 0;
+ }
+
/*
* If the bootloader already enabled the link we need some special
* handling to get the core back into a state where it is safe to
@@ -266,6 +279,21 @@ static int imx6_pcie_assert_core_reset(struct pcie_port *pp)
static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
{
+ struct pcie_port *pp = &imx6_pcie->pp;
+ int ret;
+
+ if (imx6_pcie->is_imx6sx) {
+ ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi);
+ if (ret) {
+ dev_err(pp->dev, "unable to enable pcie_axi clock\n");
+ return ret;
+ }
+
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0);
+ return ret;
+ }
+
/* power up core phy and enable ref clock */
regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
@@ -319,6 +347,11 @@ static int imx6_pcie_deassert_core_reset(struct pcie_port *pp)
msleep(100);
gpiod_set_value_cansleep(imx6_pcie->reset_gpio, 1);
}
+
+ if (imx6_pcie->is_imx6sx)
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
+ IMX6SX_GPR5_PCIE_BTNRST_RESET, 0);
+
return 0;
err_ref_clk:
@@ -336,6 +369,12 @@ static void imx6_pcie_init_phy(struct pcie_port *pp)
{
struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
+ if (imx6_pcie->is_imx6sx) {
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6SX_GPR12_PCIE_RX_EQ_MASK,
+ IMX6SX_GPR12_PCIE_RX_EQ_2);
+ }
+
regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
@@ -554,6 +593,9 @@ static int __init imx6_pcie_probe(struct platform_device *pdev)
pp = &imx6_pcie->pp;
pp->dev = &pdev->dev;
+ imx6_pcie->is_imx6sx = of_device_is_compatible(pp->dev->of_node,
+ "fsl,imx6sx-pcie");
+
/* Added for PCI abort handling */
hook_fault_code(16 + 6, imx6q_pcie_abort_handler, SIGBUS, 0,
"imprecise external abort");
@@ -589,6 +631,16 @@ static int __init imx6_pcie_probe(struct platform_device *pdev)
return PTR_ERR(imx6_pcie->pcie);
}
+ if (imx6_pcie->is_imx6sx) {
+ imx6_pcie->pcie_inbound_axi = devm_clk_get(&pdev->dev,
+ "pcie_inbound_axi");
+ if (IS_ERR(imx6_pcie->pcie_inbound_axi)) {
+ dev_err(&pdev->dev,
+ "pcie_incbound_axi clock missing or invalid\n");
+ return PTR_ERR(imx6_pcie->pcie_inbound_axi);
+ }
+ }
+
/* Grab GPR config register range */
imx6_pcie->iomuxc_gpr =
syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
@@ -615,6 +667,7 @@ static void imx6_pcie_shutdown(struct platform_device *pdev)
static const struct of_device_id imx6_pcie_of_match[] = {
{ .compatible = "fsl,imx6q-pcie", },
+ { .compatible = "fsl,imx6sx-pcie", },
{},
};
MODULE_DEVICE_TABLE(of, imx6_pcie_of_match);
--
2.1.4
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