#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
#include <linux/module.h>
#include <linux/of_gpio.h>
+#include <linux/of_device.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#define to_imx6_pcie(x) container_of(x, struct imx6_pcie, pp)
+enum imx6_pcie_variants {
+ IMX6Q,
+ IMX6SX,
+ IMX6QP,
+};
+
struct imx6_pcie {
int reset_gpio;
+ bool gpio_active_high;
struct clk *pcie_bus;
struct clk *pcie_phy;
+ struct clk *pcie_inbound_axi;
struct clk *pcie;
struct pcie_port pp;
struct regmap *iomuxc_gpr;
+ enum imx6_pcie_variants variant;
void __iomem *mem_base;
u32 tx_deemph_gen1;
u32 tx_deemph_gen2_3p5db;
u32 tx_deemph_gen2_6db;
u32 tx_swing_full;
u32 tx_swing_low;
+ int link_gen;
};
/* PCIe Root Complex registers (memory-mapped) */
struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
u32 val, gpr1, gpr12;
- /*
- * 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
- * touch it for configuration. As there is no dedicated reset signal
- * wired up for MX6QDL, we need to manually force LTSSM into "detect"
- * state before completely disabling LTSSM, which is a prerequisite
- * for core configuration.
- *
- * If both LTSSM_ENABLE and REF_SSP_ENABLE are active we have a strong
- * indication that the bootloader activated the link.
- */
- regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, &gpr1);
- regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, &gpr12);
+ switch (imx6_pcie->variant) {
+ case 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);
+ break;
+ case IMX6QP:
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
+ IMX6Q_GPR1_PCIE_SW_RST,
+ IMX6Q_GPR1_PCIE_SW_RST);
+ break;
+ case IMX6Q:
+ /*
+ * 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 touch it for configuration. As there is
+ * no dedicated reset signal wired up for MX6QDL, we need
+ * to manually force LTSSM into "detect" state before
+ * completely disabling LTSSM, which is a prerequisite for
+ * core configuration.
+ *
+ * If both LTSSM_ENABLE and REF_SSP_ENABLE are active we
+ * have a strong indication that the bootloader activated
+ * the link.
+ */
+ regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, &gpr1);
+ regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, &gpr12);
+
+ if ((gpr1 & IMX6Q_GPR1_PCIE_REF_CLK_EN) &&
+ (gpr12 & IMX6Q_GPR12_PCIE_CTL_2)) {
+ val = readl(pp->dbi_base + PCIE_PL_PFLR);
+ val &= ~PCIE_PL_PFLR_LINK_STATE_MASK;
+ val |= PCIE_PL_PFLR_FORCE_LINK;
+ writel(val, pp->dbi_base + PCIE_PL_PFLR);
+
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
+ }
+
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
+ IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
+ IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16);
+ break;
+ }
+
+ return 0;
+}
+
+static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
+{
+ struct pcie_port *pp = &imx6_pcie->pp;
+ int ret = 0;
- if ((gpr1 & IMX6Q_GPR1_PCIE_REF_CLK_EN) &&
- (gpr12 & IMX6Q_GPR12_PCIE_CTL_2)) {
- val = readl(pp->dbi_base + PCIE_PL_PFLR);
- val &= ~PCIE_PL_PFLR_LINK_STATE_MASK;
- val |= PCIE_PL_PFLR_FORCE_LINK;
- writel(val, pp->dbi_base + PCIE_PL_PFLR);
+ switch (imx6_pcie->variant) {
+ case IMX6SX:
+ ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi);
+ if (ret) {
+ dev_err(pp->dev, "unable to enable pcie_axi clock\n");
+ break;
+ }
regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
- IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
+ IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0);
+ break;
+ case IMX6QP: /* FALLTHROUGH */
+ case IMX6Q:
+ /* power up core phy and enable ref clock */
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
+ IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
+ /*
+ * the async reset input need ref clock to sync internally,
+ * when the ref clock comes after reset, internal synced
+ * reset time is too short, cannot meet the requirement.
+ * add one ~10us delay here.
+ */
+ udelay(10);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
+ IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
+ break;
}
- regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
- IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18);
- regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
- IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16);
-
- return 0;
+ return ret;
}
static int imx6_pcie_deassert_core_reset(struct pcie_port *pp)
goto err_pcie;
}
- /* power up core phy and enable ref clock */
- regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
- IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
- /*
- * the async reset input need ref clock to sync internally,
- * when the ref clock comes after reset, internal synced
- * reset time is too short, cannot meet the requirement.
- * add one ~10us delay here.
- */
- udelay(10);
- regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
- IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
+ ret = imx6_pcie_enable_ref_clk(imx6_pcie);
+ if (ret) {
+ dev_err(pp->dev, "unable to enable pcie ref clock\n");
+ goto err_ref_clk;
+ }
/* allow the clocks to stabilize */
usleep_range(200, 500);
/* Some boards don't have PCIe reset GPIO. */
if (gpio_is_valid(imx6_pcie->reset_gpio)) {
- gpio_set_value_cansleep(imx6_pcie->reset_gpio, 0);
+ gpio_set_value_cansleep(imx6_pcie->reset_gpio,
+ imx6_pcie->gpio_active_high);
msleep(100);
- gpio_set_value_cansleep(imx6_pcie->reset_gpio, 1);
+ gpio_set_value_cansleep(imx6_pcie->reset_gpio,
+ !imx6_pcie->gpio_active_high);
}
+
+ switch (imx6_pcie->variant) {
+ case IMX6SX:
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
+ IMX6SX_GPR5_PCIE_BTNRST_RESET, 0);
+ break;
+ case IMX6QP:
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
+ IMX6Q_GPR1_PCIE_SW_RST, 0);
+
+ usleep_range(200, 500);
+ break;
+ case IMX6Q: /* Nothing to do */
+ break;
+ }
+
return 0;
+err_ref_clk:
+ clk_disable_unprepare(imx6_pcie->pcie);
err_pcie:
clk_disable_unprepare(imx6_pcie->pcie_bus);
err_pcie_bus:
clk_disable_unprepare(imx6_pcie->pcie_phy);
err_pcie_phy:
return ret;
-
}
static void imx6_pcie_init_phy(struct pcie_port *pp)
{
struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
+ if (imx6_pcie->variant == 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);
goto err_reset_phy;
}
- /* Allow Gen2 mode after the link is up. */
- tmp = readl(pp->dbi_base + PCIE_RC_LCR);
- tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
- tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2;
- writel(tmp, pp->dbi_base + PCIE_RC_LCR);
+ if (imx6_pcie->link_gen == 2) {
+ /* Allow Gen2 mode after the link is up. */
+ tmp = readl(pp->dbi_base + PCIE_RC_LCR);
+ tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
+ tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2;
+ writel(tmp, pp->dbi_base + PCIE_RC_LCR);
+ } else {
+ dev_info(pp->dev, "Link: Gen2 disabled\n");
+ }
/*
* Start Directed Speed Change so the best possible speed both link
}
tmp = readl(pp->dbi_base + PCIE_RC_LCSR);
- dev_dbg(pp->dev, "Link up, Gen=%i\n", (tmp >> 16) & 0xf);
-
+ dev_info(pp->dev, "Link up, Gen%i\n", (tmp >> 16) & 0xf);
return 0;
err_reset_phy:
pp = &imx6_pcie->pp;
pp->dev = &pdev->dev;
+ imx6_pcie->variant =
+ (enum imx6_pcie_variants)of_device_get_match_data(&pdev->dev);
+
/* Added for PCI abort handling */
hook_fault_code(16 + 6, imx6q_pcie_abort_handler, SIGBUS, 0,
"imprecise external abort");
/* Fetch GPIOs */
imx6_pcie->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);
+ imx6_pcie->gpio_active_high = of_property_read_bool(np,
+ "reset-gpio-active-high");
if (gpio_is_valid(imx6_pcie->reset_gpio)) {
ret = devm_gpio_request_one(&pdev->dev, imx6_pcie->reset_gpio,
- GPIOF_OUT_INIT_LOW, "PCIe reset");
+ imx6_pcie->gpio_active_high ?
+ GPIOF_OUT_INIT_HIGH :
+ GPIOF_OUT_INIT_LOW,
+ "PCIe reset");
if (ret) {
dev_err(&pdev->dev, "unable to get reset gpio\n");
return ret;
return PTR_ERR(imx6_pcie->pcie);
}
+ if (imx6_pcie->variant == 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");
&imx6_pcie->tx_swing_low))
imx6_pcie->tx_swing_low = 127;
+ /* Limit link speed */
+ ret = of_property_read_u32(pp->dev->of_node, "fsl,max-link-speed",
+ &imx6_pcie->link_gen);
+ if (ret)
+ imx6_pcie->link_gen = 1;
+
ret = imx6_add_pcie_port(pp, pdev);
if (ret < 0)
return ret;
}
static const struct of_device_id imx6_pcie_of_match[] = {
- { .compatible = "fsl,imx6q-pcie", },
+ { .compatible = "fsl,imx6q-pcie", .data = (void *)IMX6Q, },
+ { .compatible = "fsl,imx6sx-pcie", .data = (void *)IMX6SX, },
+ { .compatible = "fsl,imx6qp-pcie", .data = (void *)IMX6QP, },
{},
};
MODULE_DEVICE_TABLE(of, imx6_pcie_of_match);
projects / deliverable / linux.git / blobdiff