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authorChristoph Fritz <chf.fritz@googlemail.com>2016-04-05 16:53:27 -0500
committerBjorn Helgaas <bhelgaas@google.com>2016-04-19 19:41:25 -0500
commite3c06cd063d69df741295a50a691d4a2cad3852a (patch)
tree1b7de07194b08614b5370d90732792299cad20d3 /drivers/pci
parent4d1821e729b5d2060ef8c9825af1dacc2182da38 (diff)
downloadlinux-e3c06cd063d69df741295a50a691d4a2cad3852a.tar.bz2
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 <chf.fritz@googlemail.com> Acked-by: Richard Zhu <Richard.Zhu@freescale.com> Acked-by: Lucas Stach <l.stach@pengutronix.de>
Diffstat (limited to 'drivers/pci')
-rw-r--r--drivers/pci/host/pci-imx6.c53
1 files changed, 53 insertions, 0 deletions
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);