Cc: [email protected]
Cc: Fabio Estevam <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: Leonard Crestez <[email protected]>
Cc: "A.s. Dong" <[email protected]>
Cc: Richard Zhu <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Andrey Smirnov <[email protected]>
---
 drivers/pci/controller/dwc/Kconfig    |   2 +-
 drivers/pci/controller/dwc/pci-imx6.c | 117 ++++++++++++++++++++++++--
 2 files changed, 113 insertions(+), 6 deletions(-)

diff --git a/drivers/pci/controller/dwc/Kconfig 
b/drivers/pci/controller/dwc/Kconfig
index 91b0194240a5..2b139acccf32 100644
--- a/drivers/pci/controller/dwc/Kconfig
+++ b/drivers/pci/controller/dwc/Kconfig
@@ -90,7 +90,7 @@ config PCI_EXYNOS
 
 config PCI_IMX6
        bool "Freescale i.MX6 PCIe controller"
-       depends on SOC_IMX6Q || (ARM && COMPILE_TEST)
+       depends on SOC_IMX8MQ || SOC_IMX6Q || (ARM && COMPILE_TEST)
        depends on PCI_MSI_IRQ_DOMAIN
        select PCIE_DW_HOST
 
diff --git a/drivers/pci/controller/dwc/pci-imx6.c 
b/drivers/pci/controller/dwc/pci-imx6.c
index 3c3002861d25..8d1f310e41a6 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -8,6 +8,7 @@
  * Author: Sean Cross <[email protected]>
  */
 
+#include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/gpio.h>
@@ -30,6 +31,14 @@
 
 #include "pcie-designware.h"
 
+#define IMX8MQ_PCIE_LINK_CAP_REG_OFFSET                0x7C
+#define IMX8MQ_PCIE_LINK_CAP_L1EL_64US         (0x6 << 15)
+
+#define IMX8MQ_GPR_PCIE_REF_USE_PAD            BIT(9)
+#define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN    BIT(10)
+#define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE       BIT(11)
+
+
 #define to_imx6_pcie(x)        dev_get_drvdata((x)->dev)
 
 enum imx6_pcie_variants {
@@ -37,6 +46,7 @@ enum imx6_pcie_variants {
        IMX6SX,
        IMX6QP,
        IMX7D,
+       IMX8MQ,
 };
 
 struct imx6_pcie {
@@ -48,8 +58,10 @@ struct imx6_pcie {
        struct clk              *pcie_inbound_axi;
        struct clk              *pcie;
        struct regmap           *iomuxc_gpr;
+       u32                     gpr1x;
        struct reset_control    *pciephy_reset;
        struct reset_control    *apps_reset;
+       struct reset_control    *apps_clk_req;
        struct reset_control    *turnoff_reset;
        enum imx6_pcie_variants variant;
        u32                     tx_deemph_gen1;
@@ -59,6 +71,7 @@ struct imx6_pcie {
        u32                     tx_swing_low;
        int                     link_gen;
        struct regulator        *vpcie;
+       u32                     device_type[2];
 };
 
 /* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */
@@ -245,7 +258,8 @@ static void imx6_pcie_reset_phy(struct imx6_pcie *imx6_pcie)
 {
        u32 tmp;
 
-       if (imx6_pcie->variant == IMX7D)
+       if (imx6_pcie->variant == IMX7D ||
+           imx6_pcie->variant == IMX8MQ)
                return;
 
        pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
@@ -261,6 +275,7 @@ static void imx6_pcie_reset_phy(struct imx6_pcie *imx6_pcie)
        pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
 }
 
+#ifdef CONFIG_ARM
 /*  Added for PCI abort handling */
 static int imx6q_pcie_abort_handler(unsigned long addr,
                unsigned int fsr, struct pt_regs *regs)
@@ -294,6 +309,7 @@ static int imx6q_pcie_abort_handler(unsigned long addr,
 
        return 1;
 }
+#endif
 
 static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
 {
@@ -301,6 +317,7 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie 
*imx6_pcie)
 
        switch (imx6_pcie->variant) {
        case IMX7D:
+       case IMX8MQ: /* FALLTHROUGH */
                reset_control_assert(imx6_pcie->pciephy_reset);
                reset_control_assert(imx6_pcie->apps_reset);
                break;
@@ -369,6 +386,18 @@ static int imx6_pcie_enable_ref_clk(struct imx6_pcie 
*imx6_pcie)
                break;
        case IMX7D:
                break;
+       case IMX8MQ:
+               /*
+                * Set the over ride low and enabled
+                * make sure that REF_CLK is turned on.
+                */
+               regmap_update_bits(imx6_pcie->iomuxc_gpr, imx6_pcie->gpr1x,
+                                  IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE,
+                                  0);
+               regmap_update_bits(imx6_pcie->iomuxc_gpr, imx6_pcie->gpr1x,
+                                  IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN,
+                                  IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN);
+               break;
        }
 
        return ret;
@@ -397,6 +426,7 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie 
*imx6_pcie)
 {
        struct dw_pcie *pci = imx6_pcie->pci;
        struct device *dev = pci->dev;
+       unsigned int val;
        int ret;
 
        if (imx6_pcie->vpcie && !regulator_is_enabled(imx6_pcie->vpcie)) {
@@ -445,6 +475,29 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie 
*imx6_pcie)
        }
 
        switch (imx6_pcie->variant) {
+       case IMX8MQ:
+               reset_control_deassert(imx6_pcie->pciephy_reset);
+               udelay(100);
+               /*
+                * Configure the CLK_REQ# high, let the L1SS
+                * automatically controlled by HW.
+                */
+               reset_control_assert(imx6_pcie->apps_clk_req);
+
+               /*
+                * Configure the L1 latency of rc to less than 64us
+                * Otherwise, the L1/L1SUB wouldn't be enable by ASPM.
+                */
+               val = dw_pcie_readl_dbi(imx6_pcie->pci,
+                                       SZ_1M +
+                                       IMX8MQ_PCIE_LINK_CAP_REG_OFFSET);
+               val &= ~PCI_EXP_LNKCAP_L1EL;
+               val |= IMX8MQ_PCIE_LINK_CAP_L1EL_64US;
+               dw_pcie_writel_dbi(imx6_pcie->pci,
+                                  SZ_1M +
+                                  IMX8MQ_PCIE_LINK_CAP_REG_OFFSET,
+                                  val);
+               break;
        case IMX7D:
                reset_control_deassert(imx6_pcie->pciephy_reset);
                imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie);
@@ -483,6 +536,15 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie 
*imx6_pcie)
 static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
 {
        switch (imx6_pcie->variant) {
+       case IMX8MQ:
+               /*
+                * TODO: Currently this code assumes external
+                * oscillator is being used
+                */
+               regmap_update_bits(imx6_pcie->iomuxc_gpr, imx6_pcie->gpr1x,
+                                  IMX8MQ_GPR_PCIE_REF_USE_PAD,
+                                  IMX8MQ_GPR_PCIE_REF_USE_PAD);
+               break;
        case IMX7D:
                regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
                                   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
@@ -519,7 +581,8 @@ static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
        }
 
        regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
-                       IMX6Q_GPR12_DEVICE_TYPE, PCI_EXP_TYPE_ROOT_PORT << 12);
+                          imx6_pcie->device_type[0],
+                          imx6_pcie->device_type[1]);
 }
 
 static int imx6_setup_phy_mpll(struct imx6_pcie *imx6_pcie)
@@ -528,7 +591,8 @@ static int imx6_setup_phy_mpll(struct imx6_pcie *imx6_pcie)
        int mult, div;
        u32 val;
 
-       if (imx6_pcie->variant == IMX7D)
+       if (imx6_pcie->variant == IMX7D ||
+           imx6_pcie->variant == IMX8MQ)
                return 0;
 
        switch (phy_rate) {
@@ -616,6 +680,7 @@ static void imx6_pcie_ltssm_enable(struct device *dev)
                                   IMX6Q_GPR12_PCIE_CTL_2);
                break;
        case IMX7D:
+       case IMX8MQ:            /* FALLTHROUGH */
                reset_control_deassert(imx6_pcie->apps_reset);
                break;
        }
@@ -798,10 +863,24 @@ static void imx6_pcie_clk_disable(struct imx6_pcie 
*imx6_pcie)
        clk_disable_unprepare(imx6_pcie->pcie_phy);
        clk_disable_unprepare(imx6_pcie->pcie_bus);
 
-       if (imx6_pcie->variant == IMX7D) {
+       switch (imx6_pcie->variant) {
+       case IMX7D:
                regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
                                   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL,
                                   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
+               break;
+       /*
+        * Disable the override. Configure the CLK_REQ# high, let the
+        * L1SS automatically controlled by HW when link is up.
+        * Otherwise, turn off the REF_CLK to save power consumption.
+        */
+       case IMX8MQ:
+               regmap_update_bits(imx6_pcie->iomuxc_gpr, imx6_pcie->gpr1x,
+                                  IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN,
+                                  0);
+               break;
+       default:
+               break;
        }
 }
 
@@ -870,6 +949,10 @@ static int imx6_pcie_probe(struct platform_device *pdev)
        imx6_pcie->variant =
                (enum imx6_pcie_variants)of_device_get_match_data(dev);
 
+       imx6_pcie->device_type[0] = IMX6Q_GPR12_DEVICE_TYPE;
+       imx6_pcie->device_type[1] = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE,
+                                              PCI_EXP_TYPE_ROOT_PORT);
+
        dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        pci->dbi_base = devm_ioremap_resource(dev, dbi_base);
        if (IS_ERR(pci->dbi_base))
@@ -921,7 +1004,28 @@ static int imx6_pcie_probe(struct platform_device *pdev)
                        return PTR_ERR(imx6_pcie->pcie_inbound_axi);
                }
                break;
-       case IMX7D:
+       case IMX8MQ:
+               if (of_property_read_u32(node, "fsl,iomux-gpr1x",
+                                        &imx6_pcie->gpr1x)) {
+                       dev_err(dev, "Failed to get GPR1x address\n");
+                       return -EINVAL;
+               }
+
+               if (of_property_read_u32_array(
+                           node, "fsl,gpr12-device-type",
+                           imx6_pcie->device_type,
+                           ARRAY_SIZE(imx6_pcie->device_type))) {
+                       dev_err(dev, "Failed to get device type mask/value\n");
+                       return -EINVAL;
+               }
+
+               imx6_pcie->apps_clk_req =
+                       devm_reset_control_get_exclusive(dev, "clkreq");
+               if (IS_ERR(imx6_pcie->apps_clk_req)) {
+                       dev_err(dev, "Failed to get PCIE APPS CLK_REQ# reset 
control\n");
+                       return PTR_ERR(imx6_pcie->apps_clk_req);
+               }
+       case IMX7D:             /* FALLTHROUGH */
                imx6_pcie->pciephy_reset = devm_reset_control_get_exclusive(dev,
                                                                            
"pciephy");
                if (IS_ERR(imx6_pcie->pciephy_reset)) {
@@ -1011,6 +1115,7 @@ static const struct of_device_id imx6_pcie_of_match[] = {
        { .compatible = "fsl,imx6sx-pcie", .data = (void *)IMX6SX, },
        { .compatible = "fsl,imx6qp-pcie", .data = (void *)IMX6QP, },
        { .compatible = "fsl,imx7d-pcie",  .data = (void *)IMX7D,  },
+       { .compatible = "fsl,imx8mq-pcie", .data = (void *)IMX8MQ, } ,
        {},
 };
 
@@ -1027,6 +1132,7 @@ static struct platform_driver imx6_pcie_driver = {
 
 static int __init imx6_pcie_init(void)
 {
+#ifdef CONFIG_ARM
        /*
         * Since probe() can be deferred we need to make sure that
         * hook_fault_code is not called after __init memory is freed
@@ -1036,6 +1142,7 @@ static int __init imx6_pcie_init(void)
         */
        hook_fault_code(8, imx6q_pcie_abort_handler, SIGBUS, 0,
                        "external abort on non-linefetch");
+#endif
 
        return platform_driver_register(&imx6_pcie_driver);
 }
-- 
2.19.1

Reply via email to