[PATCH v4] PCI: imx6: Add initial imx6sx support
Bjorn Helgaas
helgaas at kernel.org
Tue Apr 5 14:56:25 PDT 2016
On Mon, Mar 14, 2016 at 12:31:10AM +0100, Christoph Fritz wrote:
> 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 at googlemail.com>
> Acked-by: Richard Zhu <Richard.Zhu at freescale.com>
> Acked-by: Lucas Stach <l.stach at pengutronix.de>
Applied to pci/host-imx6 for v4.7, thanks!
> ---
> .../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 at 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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