On Mon, 20 Feb 2017, Andrey Smirnov wrote:
> Add various bits of code needed to support i.MX7D variant of the IP.
>
> Cc: yurovsky@xxxxxxxxx
> Cc: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> Cc: Mark Rutland <mark.rutland@xxxxxxx>
> Cc: Lee Jones <lee.jones@xxxxxxxxxx>
> Cc: Fabio Estevam <fabio.estevam@xxxxxxx>
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Cc: devicetree@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Signed-off-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx>
> ---
> .../devicetree/bindings/pci/fsl,imx6q-pcie.txt | 13 ++-
> drivers/pci/host/pci-imx6.c | 121 ++++++++++++++++-----
> include/linux/mfd/syscon/imx7-iomuxc-gpr.h | 4 +
Acked-by: Lee Jones <lee.jones@xxxxxxxxxx>
> 3 files changed, 112 insertions(+), 26 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
> index 83aeb1f..11db2ab 100644
> --- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
> +++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
> @@ -4,7 +4,11 @@ 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", "fsl,imx6sx-pcie", "fsl,imx6qp-pcie"
> +- compatible:
> + - "fsl,imx6q-pcie"
> + - "fsl,imx6sx-pcie",
> + - "fsl,imx6qp-pcie"
> + - "fsl,imx7d-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.
> @@ -34,6 +38,13 @@ Additional required properties for imx6sx-pcie:
> - clock names: Must include the following additional entries:
> - "pcie_inbound_axi"
>
> +Additional required properties for imx7d-pcie:
> +- power-domains: Must be set to a phandle pointing to PCIE_PHY power domain
> +- resets: Must contain phandles to PCIE related reset lines exposed by SRC IP block
> +- reset-names: Must contain the following entires:
> + - "pciephy"
> + - "apps"
> +
> Example:
>
> pcie@0x01000000 {
> diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
> index 50a1291..2f3f375 100644
> --- a/drivers/pci/host/pci-imx6.c
> +++ b/drivers/pci/host/pci-imx6.c
> @@ -17,6 +17,7 @@
> #include <linux/kernel.h>
> #include <linux/mfd/syscon.h>
> #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
> +#include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
> #include <linux/module.h>
> #include <linux/of_gpio.h>
> #include <linux/of_device.h>
> @@ -27,6 +28,7 @@
> #include <linux/signal.h>
> #include <linux/types.h>
> #include <linux/interrupt.h>
> +#include <linux/reset.h>
>
> #include "pcie-designware.h"
>
> @@ -36,6 +38,7 @@ enum imx6_pcie_variants {
> IMX6Q,
> IMX6SX,
> IMX6QP,
> + IMX7D,
> };
>
> struct imx6_pcie {
> @@ -47,6 +50,8 @@ struct imx6_pcie {
> struct clk *pcie_inbound_axi;
> struct clk *pcie;
> struct regmap *iomuxc_gpr;
> + struct reset_control *pciephy_reset;
> + struct reset_control *apps_reset;
> enum imx6_pcie_variants variant;
> u32 tx_deemph_gen1;
> u32 tx_deemph_gen2_3p5db;
> @@ -56,6 +61,11 @@ struct imx6_pcie {
> int link_gen;
> };
>
> +/* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */
> +#define PHY_PLL_LOCK_WAIT_MAX_RETRIES 2000
> +#define PHY_PLL_LOCK_WAIT_USLEEP_MIN 50
> +#define PHY_PLL_LOCK_WAIT_USLEEP_MAX 200
> +
> /* PCIe Root Complex registers (memory-mapped) */
> #define PCIE_RC_LCR 0x7c
> #define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1 0x1
> @@ -251,6 +261,10 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
> u32 val, gpr1, gpr12;
>
> switch (imx6_pcie->variant) {
> + case IMX7D:
> + reset_control_assert(imx6_pcie->pciephy_reset);
> + reset_control_assert(imx6_pcie->apps_reset);
> + break;
> case IMX6SX:
> regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> IMX6SX_GPR12_PCIE_TEST_POWERDOWN,
> @@ -333,11 +347,33 @@ static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
> regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
> IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
> break;
> + case IMX7D:
> + break;
> }
>
> return ret;
> }
>
> +static void imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie *imx6_pcie)
> +{
> + u32 val;
> + unsigned int retries;
> + struct pcie_port *pp = &imx6_pcie->pp;
> + struct device *dev = pp->dev;
> +
> + for (retries = 0; retries < PHY_PLL_LOCK_WAIT_MAX_RETRIES; retries++) {
> + regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR22, &val);
> +
> + if (val & IMX7D_GPR22_PCIE_PHY_PLL_LOCKED)
> + return;
> +
> + usleep_range(PHY_PLL_LOCK_WAIT_USLEEP_MIN,
> + PHY_PLL_LOCK_WAIT_USLEEP_MAX);
> + }
> +
> + dev_err(dev, "PCIe PLL lock timeout\n");
> +}
> +
> static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
> {
> struct pcie_port *pp = &imx6_pcie->pp;
> @@ -381,6 +417,10 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
> }
>
> switch (imx6_pcie->variant) {
> + case IMX7D:
> + reset_control_deassert(imx6_pcie->pciephy_reset);
> + imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie);
> + break;
> case IMX6SX:
> regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
> IMX6SX_GPR5_PCIE_BTNRST_RESET, 0);
> @@ -407,35 +447,44 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
>
> static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
> {
> - if (imx6_pcie->variant == IMX6SX)
> + switch (imx6_pcie->variant) {
> + case IMX7D:
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> + IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
> + break;
> + case IMX6SX:
> regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> IMX6SX_GPR12_PCIE_RX_EQ_MASK,
> IMX6SX_GPR12_PCIE_RX_EQ_2);
> + /* FALLTHROUGH */
> + default:
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> + IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
>
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> - IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
> + /* configure constant input signal to the pcie ctrl and phy */
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> + IMX6Q_GPR12_LOS_LEVEL, 9 << 4);
> +
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> + IMX6Q_GPR8_TX_DEEMPH_GEN1,
> + imx6_pcie->tx_deemph_gen1 << 0);
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> + IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB,
> + imx6_pcie->tx_deemph_gen2_3p5db << 6);
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> + IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB,
> + imx6_pcie->tx_deemph_gen2_6db << 12);
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> + IMX6Q_GPR8_TX_SWING_FULL,
> + imx6_pcie->tx_swing_full << 18);
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> + IMX6Q_GPR8_TX_SWING_LOW,
> + imx6_pcie->tx_swing_low << 25);
> + break;
> + }
>
> - /* configure constant input signal to the pcie ctrl and phy */
> regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> IMX6Q_GPR12_DEVICE_TYPE, PCI_EXP_TYPE_ROOT_PORT << 12);
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> - IMX6Q_GPR12_LOS_LEVEL, 9 << 4);
> -
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> - IMX6Q_GPR8_TX_DEEMPH_GEN1,
> - imx6_pcie->tx_deemph_gen1 << 0);
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> - IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB,
> - imx6_pcie->tx_deemph_gen2_3p5db << 6);
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> - IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB,
> - imx6_pcie->tx_deemph_gen2_6db << 12);
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> - IMX6Q_GPR8_TX_SWING_FULL,
> - imx6_pcie->tx_swing_full << 18);
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> - IMX6Q_GPR8_TX_SWING_LOW,
> - imx6_pcie->tx_swing_low << 25);
> }
>
> static int imx6_pcie_wait_for_link(struct imx6_pcie *imx6_pcie)
> @@ -498,8 +547,11 @@ static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie)
> dw_pcie_writel_rc(pp, PCIE_RC_LCR, tmp);
>
> /* Start LTSSM. */
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> - IMX6Q_GPR12_PCIE_CTL_2, 1 << 10);
> + if (imx6_pcie->variant == IMX7D)
> + reset_control_deassert(imx6_pcie->apps_reset);
> + else
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> + IMX6Q_GPR12_PCIE_CTL_2, 1 << 10);
>
> ret = imx6_pcie_wait_for_link(imx6_pcie);
> if (ret) {
> @@ -674,13 +726,31 @@ static int __init imx6_pcie_probe(struct platform_device *pdev)
> return PTR_ERR(imx6_pcie->pcie);
> }
>
> - if (imx6_pcie->variant == IMX6SX) {
> + switch (imx6_pcie->variant) {
> + case IMX6SX:
> imx6_pcie->pcie_inbound_axi = devm_clk_get(dev,
> "pcie_inbound_axi");
> if (IS_ERR(imx6_pcie->pcie_inbound_axi)) {
> dev_err(dev, "pcie_inbound_axi clock missing or invalid\n");
> return PTR_ERR(imx6_pcie->pcie_inbound_axi);
> }
> + break;
> + case IMX7D:
> + imx6_pcie->pciephy_reset = devm_reset_control_get(dev,
> + "pciephy");
> + if (IS_ERR(imx6_pcie->pciephy_reset)) {
> + dev_err(dev, "Failed to get PCIEPHY reset contol\n");
> + return PTR_ERR(imx6_pcie->pciephy_reset);
> + }
> +
> + imx6_pcie->apps_reset = devm_reset_control_get(dev, "apps");
> + if (IS_ERR(imx6_pcie->apps_reset)) {
> + dev_err(dev, "Failed to get PCIE APPS reset contol\n");
> + return PTR_ERR(imx6_pcie->apps_reset);
> + }
> + break;
> + default:
> + break;
> }
>
> /* Grab GPR config register range */
> @@ -738,6 +808,7 @@ static const struct of_device_id imx6_pcie_of_match[] = {
> { .compatible = "fsl,imx6q-pcie", .data = (void *)IMX6Q, },
> { .compatible = "fsl,imx6sx-pcie", .data = (void *)IMX6SX, },
> { .compatible = "fsl,imx6qp-pcie", .data = (void *)IMX6QP, },
> + { .compatible = "fsl,imx7d-pcie", .data = (void *)IMX7D, },
> {},
> };
>
> diff --git a/include/linux/mfd/syscon/imx7-iomuxc-gpr.h b/include/linux/mfd/syscon/imx7-iomuxc-gpr.h
> index 4585d61..abbd524 100644
> --- a/include/linux/mfd/syscon/imx7-iomuxc-gpr.h
> +++ b/include/linux/mfd/syscon/imx7-iomuxc-gpr.h
> @@ -44,4 +44,8 @@
>
> #define IMX7D_GPR5_CSI_MUX_CONTROL_MIPI (0x1 << 4)
>
> +#define IMX7D_GPR12_PCIE_PHY_REFCLK_SEL BIT(5)
> +
> +#define IMX7D_GPR22_PCIE_PHY_PLL_LOCKED BIT(31)
> +
> #endif /* __LINUX_IMX7_IOMUXC_GPR_H */
--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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