From e3c06cd063d69df741295a50a691d4a2cad3852a Mon Sep 17 00:00:00 2001 From: Christoph Fritz Date: Tue, 5 Apr 2016 16:53:27 -0500 Subject: PCI: imx6: Add initial imx6sx support 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 Acked-by: Richard Zhu Acked-by: Lucas Stach --- drivers/pci/host/pci-imx6.c | 53 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) (limited to 'drivers/pci') diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c index 4357f4d90d0c..7cfe00e34f58 100644 --- a/drivers/pci/host/pci-imx6.c +++ b/drivers/pci/host/pci-imx6.c @@ -35,9 +35,11 @@ struct imx6_pcie { int 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; u32 tx_deemph_gen1; u32 tx_deemph_gen2_3p5db; @@ -236,6 +238,17 @@ 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 @@ -271,6 +284,21 @@ 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); @@ -324,6 +352,11 @@ static int imx6_pcie_deassert_core_reset(struct pcie_port *pp) msleep(100); gpio_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: @@ -341,6 +374,12 @@ 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); @@ -547,6 +586,9 @@ 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"); @@ -636,6 +688,7 @@ 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); -- cgit v1.2.3