Re: [RFC PATCH 1/6] phy: exynos-pcie: Add support for Exynos PCIe phy

From: Vivek Gautam
Date: Tue Dec 27 2016 - 00:54:34 EST

Next message: Masami Hiramatsu: "[PATCH tip/master v3] kprobes: extable: Identify kprobes' insn-slots as kernel text area"
Previous message: Kweh, Hock Leong: "RE: [PATCH] net: stmmac: synchronize stmmac_open and stmmac_dvr_probe"
In reply to: Jaehoon Chung: "[RFC PATCH 1/6] phy: exynos-pcie: Add support for Exynos PCIe phy"
Next in thread: Jaehoon Chung: "Re: [RFC PATCH 1/6] phy: exynos-pcie: Add support for Exynos PCIe phy"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

Hi Jaehoon,

On Mon, Dec 26, 2016 at 10:50 AM, Jaehoon Chung <jh80.chung@xxxxxxxxxxx> wrote:
> This patch supports to use Generic Phy framework for Exynos PCIe phy.
> When Exynos that supported the pcie want to use the PCIe,
> it needs to control the phy resgister.
> But it should be more complex to control in their own PCIe device drivers.
>
> Signed-off-by: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
> ---
> drivers/phy/Kconfig | 9 ++
> drivers/phy/Makefile | 1 +
> drivers/phy/phy-exynos-pcie.c | 227 ++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 237 insertions(+)
> create mode 100644 drivers/phy/phy-exynos-pcie.c
>
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index fe00f91..94b0433 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -341,6 +341,15 @@ config PHY_EXYNOS5_USBDRD
> This driver provides PHY interface for USB 3.0 DRD controller
> present on Exynos5 SoC series.
>
> +config PHY_EXYNOS_PCIE
> + bool "Exynos PCIe PHY driver"

Is there a reason for this not being 'tristate' ?

> + depends on ARCH_EXYNOS && OF
> + depends on PCI_EXYNOS5433
> + select GENERIC_PHY
> + help
> + Enable PCIe PHY support for Exynos SoC series.

If this driver is for Exynos5433, then same should come in this help
text as well.

> + This driver provides PHY interface for Exynos PCIe controller.
> +
> config PHY_PISTACHIO_USB
> tristate "IMG Pistachio USB2.0 PHY driver"
> depends on MACH_PISTACHIO
> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> index a534cf5..586344d 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -38,6 +38,7 @@ phy-exynos-usb2-$(CONFIG_PHY_EXYNOS4X12_USB2) += phy-exynos4x12-usb2.o
> phy-exynos-usb2-$(CONFIG_PHY_EXYNOS5250_USB2) += phy-exynos5250-usb2.o
> phy-exynos-usb2-$(CONFIG_PHY_S5PV210_USB2) += phy-s5pv210-usb2.o
> obj-$(CONFIG_PHY_EXYNOS5_USBDRD) += phy-exynos5-usbdrd.o
> +obj-$(CONFIG_PHY_EXYNOS_PCIE) += phy-exynos-pcie.o
> obj-$(CONFIG_PHY_QCOM_APQ8064_SATA) += phy-qcom-apq8064-sata.o
> obj-$(CONFIG_PHY_ROCKCHIP_USB) += phy-rockchip-usb.o
> obj-$(CONFIG_PHY_ROCKCHIP_INNO_USB2) += phy-rockchip-inno-usb2.o
> diff --git a/drivers/phy/phy-exynos-pcie.c b/drivers/phy/phy-exynos-pcie.c
> new file mode 100644
> index 0000000..0f5eefd
> --- /dev/null
> +++ b/drivers/phy/phy-exynos-pcie.c
> @@ -0,0 +1,227 @@
> +/*
> + * Samsung EXYNOS SoC series PCIe PHY driver
> + *
> + * Phy provider for PCIe controller on Exynos SoC series
> + *
> + * Copyright (C) 2016 Samsung Electronics Co., Ltd.
> + * Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_platform.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/mfd/syscon.h>

nit: It's good to have these includes in alphabetical order.

> +
> +#define PCIE_EXYNOS5433_PMU_PHY_OFFSET 0x730
> +#define PCIE_PHY_OFFSET(x) ((x) * 0x4)
> +
> +/* Sysreg Fsys register offset and bit for Exynos5433 */
> +#define PCIE_PHY_MAC_RESET 0x208
> +#define PCIE_MAC_RESET_MASK 0xFF
> +#define PCIE_MAC_RESET BIT(4)
> +#define PCIE_L1SUB_CM_CON 0x1010
> +#define PCIE_REFCLK_GATING_EN BIT(0)
> +#define PCIE_PHY_COMMON_RESET 0x1020
> +#define PCIE_PHY_RESET BIT(0)
> +#define PCIE_PHY_GLOBAL_RESET 0x1040
> +#define PCIE_GLOBAL_RESET BIT(0)
> +#define PCIE_REFCLK BIT(1)
> +#define PCIE_REFCLK_MASK 0x16
> +#define PCIE_APP_REQ_EXIT_L1_MODE BIT(5)
> +
> +enum exynos_pcie_phy_data_type {
> + PCIE_PHY_TYPE_EXYNOS5433,
> +};
> +
> +struct exynos_pcie_phy_data {
> + enum exynos_pcie_phy_data_type ctrl_type;

Why do we need this controller type ?
If there are changes in the IP between different version,
then you can as well use different compatibles.

> + u32 pmureg_offset; /* PMU_REG offset */

Please use top comments.

> + struct phy_ops *ops;
> +};
> +
> +/* for Exynos pcie phy */
> +struct exynos_pcie_phy {
> + const struct exynos_pcie_phy_data *drv_data;
> + struct regmap *pmureg;
> + struct regmap *fsysreg;
> + void __iomem *phy_base;

just 'base' ?

> +};
> +
> +static void exynos_pcie_phy_writel(void __iomem *base, u32 val, u32 offset)
> +{
> + writel(val, base + offset);
> +}
> +
> +static int exynos_pcie_phy_init(struct phy *phy)
> +{
> + struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
> +
> + if (ep->fsysreg) {
> + regmap_update_bits(ep->fsysreg, PCIE_PHY_COMMON_RESET,
> + PCIE_PHY_RESET, 1);
> + regmap_update_bits(ep->fsysreg, PCIE_PHY_MAC_RESET,
> + PCIE_MAC_RESET, 0);
> + /* PHY refclk 24MHz */
> + regmap_update_bits(ep->fsysreg, PCIE_PHY_GLOBAL_RESET,
> + PCIE_REFCLK_MASK, PCIE_REFCLK);
> + regmap_update_bits(ep->fsysreg, PCIE_PHY_GLOBAL_RESET,
> + PCIE_GLOBAL_RESET, 0);
> + }
> +
> + exynos_pcie_phy_writel(ep->phy_base, 0x11, PCIE_PHY_OFFSET(0x3));
> +
> + /* band gap reference on */
> + exynos_pcie_phy_writel(ep->phy_base, 0, PCIE_PHY_OFFSET(0x20));
> + exynos_pcie_phy_writel(ep->phy_base, 0, PCIE_PHY_OFFSET(0x4b));
> +
> + /* jitter tunning */
> + exynos_pcie_phy_writel(ep->phy_base, 0x34, PCIE_PHY_OFFSET(0x4));
> + exynos_pcie_phy_writel(ep->phy_base, 0x02, PCIE_PHY_OFFSET(0x7));
> + exynos_pcie_phy_writel(ep->phy_base, 0x41, PCIE_PHY_OFFSET(0x21));
> + exynos_pcie_phy_writel(ep->phy_base, 0x7F, PCIE_PHY_OFFSET(0x14));
> + exynos_pcie_phy_writel(ep->phy_base, 0xC0, PCIE_PHY_OFFSET(0x15));
> + exynos_pcie_phy_writel(ep->phy_base, 0x61, PCIE_PHY_OFFSET(0x36));
> +
> + /* D0 uninit.. */
> + exynos_pcie_phy_writel(ep->phy_base, 0x44, PCIE_PHY_OFFSET(0x3D));
> +
> + /* 24MHz */
> + exynos_pcie_phy_writel(ep->phy_base, 0x94, PCIE_PHY_OFFSET(0x8));
> + exynos_pcie_phy_writel(ep->phy_base, 0xA7, PCIE_PHY_OFFSET(0x9));
> + exynos_pcie_phy_writel(ep->phy_base, 0x93, PCIE_PHY_OFFSET(0xA));
> + exynos_pcie_phy_writel(ep->phy_base, 0x6B, PCIE_PHY_OFFSET(0xC));
> + exynos_pcie_phy_writel(ep->phy_base, 0xA5, PCIE_PHY_OFFSET(0xF));
> + exynos_pcie_phy_writel(ep->phy_base, 0x34, PCIE_PHY_OFFSET(0x16));
> + exynos_pcie_phy_writel(ep->phy_base, 0xA3, PCIE_PHY_OFFSET(0x17));
> + exynos_pcie_phy_writel(ep->phy_base, 0xA7, PCIE_PHY_OFFSET(0x1A));
> + exynos_pcie_phy_writel(ep->phy_base, 0x71, PCIE_PHY_OFFSET(0x23));
> + exynos_pcie_phy_writel(ep->phy_base, 0x4C, PCIE_PHY_OFFSET(0x24));
> +
> + exynos_pcie_phy_writel(ep->phy_base, 0x0E, PCIE_PHY_OFFSET(0x26));
> + exynos_pcie_phy_writel(ep->phy_base, 0x14, PCIE_PHY_OFFSET(0x7));
> + exynos_pcie_phy_writel(ep->phy_base, 0x48, PCIE_PHY_OFFSET(0x43));
> + exynos_pcie_phy_writel(ep->phy_base, 0x44, PCIE_PHY_OFFSET(0x44));
> + exynos_pcie_phy_writel(ep->phy_base, 0x03, PCIE_PHY_OFFSET(0x45));
> + exynos_pcie_phy_writel(ep->phy_base, 0xA7, PCIE_PHY_OFFSET(0x48));
> + exynos_pcie_phy_writel(ep->phy_base, 0x13, PCIE_PHY_OFFSET(0x54));
> + exynos_pcie_phy_writel(ep->phy_base, 0x04, PCIE_PHY_OFFSET(0x31));
> + exynos_pcie_phy_writel(ep->phy_base, 0, PCIE_PHY_OFFSET(0x32));
> +
> + if (ep->fsysreg) {
> + regmap_update_bits(ep->fsysreg, PCIE_PHY_COMMON_RESET,
> + PCIE_PHY_RESET, 0);
> + regmap_update_bits(ep->fsysreg, PCIE_PHY_MAC_RESET,
> + PCIE_MAC_RESET_MASK, PCIE_MAC_RESET);
> + }
> +
> + return 0;
> +}
> +
> +static int exynos_pcie_phy_power_on(struct phy *phy)
> +{
> + struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
> +
> + if (ep->pmureg) {
> + if (regmap_update_bits(ep->pmureg, ep->drv_data->pmureg_offset,
> + BIT(0), 1))
> + dev_warn(&phy->dev, "Failed to update regmap bit.\n");
> + }
> +
> + if (ep->fsysreg) {
> + regmap_update_bits(ep->fsysreg, PCIE_PHY_GLOBAL_RESET,
> + PCIE_APP_REQ_EXIT_L1_MODE, 0);
> + regmap_update_bits(ep->fsysreg, PCIE_L1SUB_CM_CON,
> + PCIE_REFCLK_GATING_EN, 0);
> + }
> +
> + return 0;
> +}
> +
> +static struct phy_ops exynos_phy_ops = {

const ?

> + .init = exynos_pcie_phy_init,
> + .power_on = exynos_pcie_phy_power_on,
> +};
> +
> +static const struct exynos_pcie_phy_data exynos5433_pcie_phy_data = {
> + .ctrl_type = PCIE_PHY_TYPE_EXYNOS5433,
> + .pmureg_offset = PCIE_EXYNOS5433_PMU_PHY_OFFSET,
> + .ops = &exynos_phy_ops,
> +};
> +
> +static const struct of_device_id exynos_pcie_phy_match[] = {
> + {
> + .compatible = "samsung,exynos5433-pcie-phy",
> + .data = &exynos5433_pcie_phy_data,
> + },
> + {}

missing comma after braces.

> +};
> +MODULE_DEVICE_TABLE(of, exynos_pcie_phy_match);
> +
> +static int exynos_pcie_phy_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *np = dev->of_node;
> + struct exynos_pcie_phy *exynos_phy;
> + struct phy *generic_phy;
> + struct phy_provider *phy_provider;
> + struct resource *res;
> + const struct exynos_pcie_phy_data *drv_data;
> + const struct of_device_id *match;
> +
> + exynos_phy = devm_kzalloc(dev, sizeof(*exynos_phy), GFP_KERNEL);
> + if (!exynos_phy)
> + return -ENOMEM;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + exynos_phy->phy_base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(exynos_phy->phy_base))
> + return PTR_ERR(exynos_phy->phy_base);
> +
> + exynos_phy->pmureg = syscon_regmap_lookup_by_phandle(np,
> + "samsung,pmureg-phandle");
> + if (IS_ERR(exynos_phy->pmureg)) {
> + dev_warn(&pdev->dev, "pmureg syscon regmap lookup failed.\n");
> + exynos_phy->pmureg = NULL;
> + }

Is this really optional ? There should be a failure path for IP versions that
require this compulsorily.

> +
> + match = of_match_node(exynos_pcie_phy_match, pdev->dev.of_node);
> + drv_data = match->data;

Please use of_device_get_match_data().

> + exynos_phy->drv_data = drv_data;
> +
> + exynos_phy->fsysreg = syscon_regmap_lookup_by_phandle(np,
> + "samsung,fsys-sysreg");
> + if (IS_ERR(exynos_phy->fsysreg)) {
> + dev_warn(&pdev->dev, "Fsysreg syscon regmap lookup failed.\n");
> + exynos_phy->fsysreg = NULL;
> + }

Same here, is this optional ?

> +
> + generic_phy = devm_phy_create(dev, dev->of_node, drv_data->ops);
> + if (IS_ERR(generic_phy)) {
> + dev_err(dev, "failed to create PHY\n");
> + return PTR_ERR(generic_phy);
> + }
> +
> + phy_set_drvdata(generic_phy, exynos_phy);
> + phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
> +
> + return PTR_ERR_OR_ZERO(phy_provider);
> +}
> +
> +static struct platform_driver exynos_pcie_phy_driver = {
> + .probe = exynos_pcie_phy_probe,
> + .driver = {
> + .of_match_table = exynos_pcie_phy_match,
> + .name = "exynos_pcie_phy",
> + }
> +};
> +module_platform_driver(exynos_pcie_phy_driver);
> --
> 2.10.2
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html

Thanks
Vivek
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

Next message: Masami Hiramatsu: "[PATCH tip/master v3] kprobes: extable: Identify kprobes' insn-slots as kernel text area"
Previous message: Kweh, Hock Leong: "RE: [PATCH] net: stmmac: synchronize stmmac_open and stmmac_dvr_probe"
In reply to: Jaehoon Chung: "[RFC PATCH 1/6] phy: exynos-pcie: Add support for Exynos PCIe phy"
Next in thread: Jaehoon Chung: "Re: [RFC PATCH 1/6] phy: exynos-pcie: Add support for Exynos PCIe phy"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]