Re: [PATCH v4 2/4] phy: qcom-snps: Add SNPS USB PHY driver for QCOM based SOCs

[Manu Gautam]

On 3/31/2020 1:06 AM, Wesley Cheng wrote:
> This adds the SNPS FemtoPHY driver used in QCOM SOCs.  There
> are potentially multiple instances of this UTMI PHY on the
> SOC, all which can utilize this driver.
>
> Signed-off-by: Wesley Cheng <wcheng@xxxxxxxxxxxxxx>
> Reviewed-by: Philipp Zabel <pza@xxxxxxxxxxxxxx>
> ---
>  drivers/phy/qualcomm/Kconfig             |  10 ++
>  drivers/phy/qualcomm/Makefile            |   1 +
>  drivers/phy/qualcomm/phy-qcom-snps-7nm.c | 294 +++++++++++++++++++++++++++++++
>  3 files changed, 305 insertions(+)
>  create mode 100644 drivers/phy/qualcomm/phy-qcom-snps-7nm.c
>
> diff --git a/drivers/phy/qualcomm/Kconfig b/drivers/phy/qualcomm/Kconfig
> index e46824d..3158c14 100644
> --- a/drivers/phy/qualcomm/Kconfig
> +++ b/drivers/phy/qualcomm/Kconfig
> @@ -85,6 +85,16 @@ config PHY_QCOM_USB_HS
>  	  Support for the USB high-speed ULPI compliant phy on Qualcomm
>  	  chipsets.
>  
> +config PHY_QCOM_USB_SNPS_HS_7NM
> +	tristate "Qualcomm 7nm USB HS PHY module"

Should we really refer this as 7nm PHY or just femto-v2 PHY? femto-v1 being the
one that is used on 28nm.
And we can add this to binding as well -

- "qcom,usb-snps-femto-v2-phy",
- "qcom,usb-snps-hs-7nm-phy",
- "qcom,sm8150-usb-hs-phy",

> +	depends on OF && (ARCH_QCOM || COMPILE_TEST)
> +	select GENERIC_PHY
> +	help
> +	  Enable support for the USB high-speed SNPS phy on Qualcomm 7nm
> +	  chipsets.  This PHY has differences in the register map compared
> +	  to the 28nm variant.  The PHY is paired with a Synopsys DWC3 USB
> +	  controller on MSM SOCs.
> +
>  config PHY_QCOM_USB_HSIC
>  	tristate "Qualcomm USB HSIC ULPI PHY module"
>  	depends on USB_ULPI_BUS
> diff --git a/drivers/phy/qualcomm/Makefile b/drivers/phy/qualcomm/Makefile
> index 283251d..06bdb40 100644
> --- a/drivers/phy/qualcomm/Makefile
> +++ b/drivers/phy/qualcomm/Makefile
> @@ -10,3 +10,4 @@ obj-$(CONFIG_PHY_QCOM_UFS_14NM)		+= phy-qcom-ufs-qmp-14nm.o
>  obj-$(CONFIG_PHY_QCOM_UFS_20NM)		+= phy-qcom-ufs-qmp-20nm.o
>  obj-$(CONFIG_PHY_QCOM_USB_HS) 		+= phy-qcom-usb-hs.o
>  obj-$(CONFIG_PHY_QCOM_USB_HSIC) 	+= phy-qcom-usb-hsic.o
> +obj-$(CONFIG_PHY_QCOM_USB_SNPS_HS_7NM)		+= phy-qcom-snps-7nm.o
> diff --git a/drivers/phy/qualcomm/phy-qcom-snps-7nm.c b/drivers/phy/qualcomm/phy-qcom-snps-7nm.c
> new file mode 100644
> index 0000000..00a46cd
> --- /dev/null
> +++ b/drivers/phy/qualcomm/phy-qcom-snps-7nm.c
> @@ -0,0 +1,294 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2020, The Linux Foundation. All rights reserved.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/reset.h>
> +#include <linux/slab.h>
> +
> +#define USB2_PHY_USB_PHY_UTMI_CTRL0		(0x3c)
> +#define OPMODE_MASK					GENMASK(4, 3)
> +#define OPMODE_NORMAL				(0x00)
> +#define OPMODE_NONDRIVING			BIT(3)
> +#define SLEEPM						BIT(0)
> +#define TERMSEL						BIT(5)
> +
> +#define USB2_PHY_USB_PHY_UTMI_CTRL1		(0x40)
> +#define XCVRSEL						BIT(0)
> +
> +#define USB2_PHY_USB_PHY_UTMI_CTRL5		(0x50)
> +#define POR							BIT(1)
> +
> +#define USB2_PHY_USB_PHY_HS_PHY_CTRL_COMMON0	(0x54)
> +#define RETENABLEN							BIT(3)
> +#define FSEL_MASK							GENMASK(7, 5)
> +#define FSEL_DEFAULT						(0x3 << 4)
> +
> +#define USB2_PHY_USB_PHY_HS_PHY_CTRL_COMMON1	(0x58)
> +#define VBUSVLDEXTSEL0						BIT(4)
> +#define PLLBTUNE							BIT(5)
> +
> +#define USB2_PHY_USB_PHY_HS_PHY_CTRL_COMMON2	(0x5c)
> +#define VREGBYPASS							BIT(0)
> +
> +#define USB2_PHY_USB_PHY_HS_PHY_CTRL1	(0x60)
> +#define VBUSVLDEXT0					BIT(0)
> +
> +#define USB2_PHY_USB_PHY_HS_PHY_CTRL2	(0x64)
> +#define USB2_AUTO_RESUME			BIT(0)
> +#define USB2_SUSPEND_N				BIT(2)
> +#define USB2_SUSPEND_N_SEL			BIT(3)
> +
> +#define USB2_PHY_USB_PHY_CFG0					(0x94)
> +#define UTMI_PHY_DATAPATH_CTRL_OVERRIDE_EN	BIT(0)
> +#define UTMI_PHY_CMN_CTRL_OVERRIDE_EN		BIT(1)
> +
> +#define USB2_PHY_USB_PHY_REFCLK_CTRL	(0xa0)
> +#define REFCLK_SEL_MASK				GENMASK(1, 0)
> +#define REFCLK_SEL_DEFAULT			(0x2 << 0)
> +
> +static const char * const qcom_snps_hsphy_vreg_names[] = {
> +	"vdda-pll", "vdda33", "vdda18",
> +};
> +
> +#define SNPS_HS_NUM_VREGS		ARRAY_SIZE(qcom_snps_hsphy_vreg_names)
> +
> +/**
> + * struct qcom_snps_hsphy - structure holding snps hs phy attributes
> + *
> + * @phy: generic phy
> + * @base: iomapped memory space for qubs2 phy
> + *
> + * @cfg_ahb_clk: AHB2PHY interface clock
> + * @ref_clk: phy reference clock
> + * @iface_clk: phy interface clock
> + * @phy_reset: phy reset control
> + * @vregs: regulator supplies bulk data
> +
> + * @phy_initialized: if PHY has been initialized correctly
> + *
> + */
> +struct qcom_snps_hsphy {
> +	struct phy *phy;
> +	void __iomem *base;
> +
> +	struct clk *cfg_ahb_clk;
> +	struct clk *ref_clk;
> +	struct reset_control *phy_reset;
> +	struct regulator_bulk_data vregs[SNPS_HS_NUM_VREGS];
> +
> +	bool phy_initialized;
> +};
> +
> +static inline void qcom_snps_hsphy_write_mask(void __iomem *base, u32 offset,
> +				    u32 mask, u32 val)
> +{
> +	u32 reg;
> +
> +	reg = readl(base + offset);
> +	reg &= ~mask;
> +	reg |= val & mask;
> +	writel(reg, base + offset);
> +
> +	/* Ensure above write is completed */
> +	readl(base + offset);
> +}
> +
> +static int qcom_snps_hsphy_init(struct phy *phy)
> +{
> +	struct qcom_snps_hsphy *hsphy = phy_get_drvdata(phy);
> +	int ret;
> +
> +	dev_vdbg(&phy->dev, "%s(): Initializing SNPS HS phy\n", __func__);
> +
> +	/* turn on regulator supplies */
> +	ret = regulator_bulk_enable(ARRAY_SIZE(hsphy->vregs), hsphy->vregs);
> +	if (ret)
> +		return ret;
> +
> +	/* enable ahb interface clock to program phy */
> +	ret = clk_prepare_enable(hsphy->cfg_ahb_clk);
> +	if (ret) {
> +		dev_err(&phy->dev, "failed to enable cfg ahb clock, %d\n", ret);
> +		goto poweroff_phy;
> +	}
> +
> +	/* Perform phy reset */
> +	ret = reset_control_assert(hsphy->phy_reset);
> +	if (ret) {
> +		dev_err(&phy->dev, "failed to assert phy_reset, %d\n", ret);
> +		goto disable_ahb_clk;
> +	}
> +
> +	/* 100 us delay to keep PHY in reset mode */
> +	usleep_range(100, 150);
> +
> +	ret = reset_control_deassert(hsphy->phy_reset);
> +	if (ret) {
> +		dev_err(&phy->dev, "failed to de-assert phy_reset, %d\n", ret);
> +		goto disable_ahb_clk;
> +	}
> +
> +	qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_CFG0,
> +							UTMI_PHY_CMN_CTRL_OVERRIDE_EN,
> +							UTMI_PHY_CMN_CTRL_OVERRIDE_EN);
> +	qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_UTMI_CTRL5,
> +							POR, POR);
> +	qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_HS_PHY_CTRL_COMMON0,
> +							FSEL_MASK, 0);
> +	qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_HS_PHY_CTRL_COMMON1,
> +					PLLBTUNE, PLLBTUNE);
> +	qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_REFCLK_CTRL,
> +					REFCLK_SEL_DEFAULT, REFCLK_SEL_MASK);
> +	qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_HS_PHY_CTRL_COMMON1,
> +					VBUSVLDEXTSEL0, VBUSVLDEXTSEL0);
> +	qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_HS_PHY_CTRL1,
> +					VBUSVLDEXT0, VBUSVLDEXT0);
> +
> +	qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_HS_PHY_CTRL_COMMON2,
> +					VREGBYPASS, VREGBYPASS);
> +
> +	qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_HS_PHY_CTRL2,
> +					USB2_SUSPEND_N_SEL | USB2_SUSPEND_N,
> +					USB2_SUSPEND_N_SEL | USB2_SUSPEND_N);
> +
> +	qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_UTMI_CTRL0,
> +					SLEEPM, SLEEPM);
> +
> +	qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_UTMI_CTRL5,
> +					POR, 0);
> +
> +	qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_HS_PHY_CTRL2,
> +					USB2_SUSPEND_N_SEL, 0);
> +
> +	qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_CFG0,
> +					UTMI_PHY_CMN_CTRL_OVERRIDE_EN, 0);
> +
> +	hsphy->phy_initialized = true;
> +
> +	return 0;
> +
> +disable_ahb_clk:
> +	clk_disable_unprepare(hsphy->cfg_ahb_clk);
> +poweroff_phy:
> +	regulator_bulk_disable(ARRAY_SIZE(hsphy->vregs), hsphy->vregs);
> +
> +	return ret;
> +}
> +
> +static int qcom_snps_hsphy_exit(struct phy *phy)
> +{
> +	struct qcom_snps_hsphy *hsphy = phy_get_drvdata(phy);
> +
> +	reset_control_assert(hsphy->phy_reset);
> +	clk_disable_unprepare(hsphy->cfg_ahb_clk);
> +	regulator_bulk_disable(ARRAY_SIZE(hsphy->vregs), hsphy->vregs);
> +	hsphy->phy_initialized = false;
> +
> +	return 0;
> +}
> +
> +static const struct phy_ops qcom_snps_hsphy_gen_ops = {
> +	.init		= qcom_snps_hsphy_init,
> +	.exit		= qcom_snps_hsphy_exit,
> +	.owner		= THIS_MODULE,
> +};
> +
> +static const struct of_device_id qcom_snps_hsphy_of_match_table[] = {
> +	{
> +		.compatible	= "qcom,sm8150-usb-hs-phy",
> +	},
> +	{
> +		.compatible	= "qcom,usb-snps-hs-7nm-phy",
> +	},
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, qcom_snps_hsphy_of_match_table);
> +
> +static int qcom_snps_hsphy_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct qcom_snps_hsphy *hsphy;
> +	struct phy_provider *phy_provider;
> +	struct phy *generic_phy;
> +	struct resource *res;
> +	int ret, i;
> +	int num;
> +
> +	hsphy = devm_kzalloc(dev, sizeof(*hsphy), GFP_KERNEL);
> +	if (!hsphy)
> +		return -ENOMEM;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	hsphy->base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(hsphy->base))
> +		return PTR_ERR(hsphy->base);
> +
> +	hsphy->ref_clk = devm_clk_get(dev, "ref");
> +	if (IS_ERR(hsphy->ref_clk)) {
> +		ret = PTR_ERR(hsphy->ref_clk);
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(dev, "failed to get ref clk, %d\n", ret);
> +		return ret;
> +	}
> +
> +	hsphy->phy_reset = devm_reset_control_get_exclusive(&pdev->dev, NULL);
> +	if (IS_ERR(hsphy->phy_reset)) {
> +		dev_err(dev, "failed to get phy core reset\n");
> +		return PTR_ERR(hsphy->phy_reset);
> +	}
> +
> +	num = ARRAY_SIZE(hsphy->vregs);
> +	for (i = 0; i < num; i++)
> +		hsphy->vregs[i].supply = qcom_snps_hsphy_vreg_names[i];
> +
> +	ret = devm_regulator_bulk_get(dev, num, hsphy->vregs);
> +	if (ret) {
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(dev, "failed to get regulator supplies: %d\n",
> +				ret);
> +		return ret;
> +	}
> +
> +	generic_phy = devm_phy_create(dev, NULL, &qcom_snps_hsphy_gen_ops);
> +	if (IS_ERR(generic_phy)) {
> +		ret = PTR_ERR(generic_phy);
> +		dev_err(dev, "failed to create phy, %d\n", ret);
> +		return ret;
> +	}
> +	hsphy->phy = generic_phy;
> +
> +	dev_set_drvdata(dev, hsphy);
> +	phy_set_drvdata(generic_phy, hsphy);
> +
> +	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
> +	if (!IS_ERR(phy_provider))
> +		dev_info(dev, "Registered Qcom-SNPS HS phy\n");
> +
> +	return PTR_ERR_OR_ZERO(phy_provider);
> +}
> +
> +static struct platform_driver qcom_snps_hsphy_driver = {
> +	.probe		= qcom_snps_hsphy_probe,
> +	.driver = {
> +		.name	= "qcom-snps-hs-7nm-phy",
> +		.of_match_table = qcom_snps_hsphy_of_match_table,
> +	},
> +};
> +
> +module_platform_driver(qcom_snps_hsphy_driver);
> +
> +MODULE_DESCRIPTION("Qualcomm 7nm USB HS PHY driver");
> +MODULE_LICENSE("GPL v2");

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