Re: [PATCH v7 1/2] phy: qcom: Add driver for QCOM IPQ806x SATA PHY

[Kishon Vijay Abraham I <kishon@ti.com>]

Hi,

On Tuesday 15 July 2014 10:09 PM, Kumar Gala wrote:
> Add a PHY driver for uses with AHCI based SATA controller driver on the
> IPQ806x family of SoCs.
> 
> Signed-off-by: Kumar Gala <galak@codeaurora.org>

Please fix this checkpatch warning..

WARNING: memory barrier without comment
#235: FILE: drivers/phy/phy-qcom-ipq806x-sata.c:101:
+	mb();

total: 0 errors, 1 warnings, 223 lines checked

-Kishon
> ---
> v7:
> * Fix compilation issues due to change in devm_phy_create API
> 
> v6:
> * Add platform_set_drvdata
> 
> v5:
> * Fix copy/paste error when killing qcom_ipq806x_sata_delay_us
> 
> v4:
> * removed qcom_ipq806x_sata_delay_us as it was only used one
> 
> v3:
> * Added Kconfig HAS_IOMEM dep
> * re-ordered probe function so phy_provider_register is last
>  
> v2:
> * dropped unused dev pointer in struct qcom_ipq806x_sata_phy
> * remove unnecessary reg initializaiton
> * Removed unneeded error message
> * Added remove function to disable the clock
> 
>  drivers/phy/Kconfig                 |   7 ++
>  drivers/phy/Makefile                |   1 +
>  drivers/phy/phy-qcom-ipq806x-sata.c | 208 ++++++++++++++++++++++++++++++++++++
>  3 files changed, 216 insertions(+)
>  create mode 100644 drivers/phy/phy-qcom-ipq806x-sata.c
> 
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index 1704fd4..3e251aa 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -191,4 +191,11 @@ config PHY_QCOM_APQ8064_SATA
>  	depends on OF
>  	select GENERIC_PHY
>  
> +config PHY_QCOM_IPQ806X_SATA
> +	tristate "Qualcomm IPQ806x SATA SerDes/PHY driver"
> +	depends on ARCH_QCOM
> +	depends on HAS_IOMEM
> +	depends on OF
> +	select GENERIC_PHY
> +
>  endmenu
> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> index 3c2ad59..54ab978 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -23,3 +23,4 @@ phy-exynos-usb2-$(CONFIG_PHY_EXYNOS5250_USB2)	+= phy-exynos5250-usb2.o
>  obj-$(CONFIG_PHY_EXYNOS5_USBDRD)	+= phy-exynos5-usbdrd.o
>  obj-$(CONFIG_PHY_XGENE)			+= phy-xgene.o
>  obj-$(CONFIG_PHY_QCOM_APQ8064_SATA)	+= phy-qcom-apq8064-sata.o
> +obj-$(CONFIG_PHY_QCOM_IPQ806X_SATA)	+= phy-qcom-ipq806x-sata.o
> diff --git a/drivers/phy/phy-qcom-ipq806x-sata.c b/drivers/phy/phy-qcom-ipq806x-sata.c
> new file mode 100644
> index 0000000..2199627
> --- /dev/null
> +++ b/drivers/phy/phy-qcom-ipq806x-sata.c
> @@ -0,0 +1,208 @@
> +/*
> + * Copyright (c) 2014, The Linux Foundation. All rights reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/time.h>
> +#include <linux/delay.h>
> +#include <linux/clk.h>
> +#include <linux/slab.h>
> +#include <linux/platform_device.h>
> +#include <linux/phy/phy.h>
> +
> +struct qcom_ipq806x_sata_phy {
> +	void __iomem *mmio;
> +	struct clk *cfg_clk;
> +	struct device *dev;
> +};
> +
> +#define __set(v, a, b)	(((v) << (b)) & GENMASK(a, b))
> +
> +#define SATA_PHY_P0_PARAM0		0x200
> +#define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3(x)	__set(x, 17, 12)
> +#define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3_MASK	GENMASK(17, 12)
> +#define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN2(x)	__set(x, 11, 6)
> +#define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN2_MASK	GENMASK(11, 6)
> +#define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN1(x)	__set(x, 5, 0)
> +#define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN1_MASK	GENMASK(5, 0)
> +
> +#define SATA_PHY_P0_PARAM1		0x204
> +#define SATA_PHY_P0_PARAM1_RESERVED_BITS31_21(x)	__set(x, 31, 21)
> +#define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3(x)	__set(x, 20, 14)
> +#define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3_MASK	GENMASK(20, 14)
> +#define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2(x)	__set(x, 13, 7)
> +#define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2_MASK	GENMASK(13, 7)
> +#define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1(x)	__set(x, 6, 0)
> +#define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1_MASK	GENMASK(6, 0)
> +
> +#define SATA_PHY_P0_PARAM2		0x208
> +#define SATA_PHY_P0_PARAM2_RX_EQ(x)	__set(x, 20, 18)
> +#define SATA_PHY_P0_PARAM2_RX_EQ_MASK	GENMASK(20, 18)
> +
> +#define SATA_PHY_P0_PARAM3		0x20C
> +#define SATA_PHY_SSC_EN			0x8
> +#define SATA_PHY_P0_PARAM4		0x210
> +#define SATA_PHY_REF_SSP_EN		0x2
> +#define SATA_PHY_RESET			0x1
> +
> +static int qcom_ipq806x_sata_phy_init(struct phy *generic_phy)
> +{
> +	struct qcom_ipq806x_sata_phy *phy = phy_get_drvdata(generic_phy);
> +	u32 reg;
> +
> +	/* Setting SSC_EN to 1 */
> +	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM3);
> +	reg = reg | SATA_PHY_SSC_EN;
> +	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM3);
> +
> +	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM0) &
> +			~(SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3_MASK |
> +			  SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN2_MASK |
> +			  SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN1_MASK);
> +	reg |= SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3(0xf);
> +	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM0);
> +
> +	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM1) &
> +			~(SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3_MASK |
> +			  SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2_MASK |
> +			  SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1_MASK);
> +	reg |= SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3(0x55) |
> +		SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2(0x55) |
> +		SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1(0x55);
> +	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM1);
> +
> +	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM2) &
> +		~SATA_PHY_P0_PARAM2_RX_EQ_MASK;
> +	reg |= SATA_PHY_P0_PARAM2_RX_EQ(0x3);
> +	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM2);
> +
> +	/* Setting PHY_RESET to 1 */
> +	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
> +	reg = reg | SATA_PHY_RESET;
> +	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
> +
> +	/* Setting REF_SSP_EN to 1 */
> +	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
> +	reg = reg | SATA_PHY_REF_SSP_EN | SATA_PHY_RESET;
> +	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
> +	mb();
> +	/* sleep for max. 50us more to combine processor wakeups */
> +	usleep_range(20, 20 + 50);
> +
> +	/* Clearing PHY_RESET to 0 */
> +	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
> +	reg = reg & ~SATA_PHY_RESET;
> +	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
> +
> +	return 0;
> +}
> +
> +static int qcom_ipq806x_sata_phy_exit(struct phy *generic_phy)
> +{
> +	struct qcom_ipq806x_sata_phy *phy = phy_get_drvdata(generic_phy);
> +	u32 reg;
> +
> +	/* Setting PHY_RESET to 1 */
> +	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
> +	reg = reg | SATA_PHY_RESET;
> +	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
> +
> +	return 0;
> +}
> +
> +static struct phy_ops qcom_ipq806x_sata_phy_ops = {
> +	.init		= qcom_ipq806x_sata_phy_init,
> +	.exit		= qcom_ipq806x_sata_phy_exit,
> +	.owner		= THIS_MODULE,
> +};
> +
> +static int qcom_ipq806x_sata_phy_probe(struct platform_device *pdev)
> +{
> +	struct qcom_ipq806x_sata_phy *phy;
> +	struct device *dev = &pdev->dev;
> +	struct resource *res;
> +	struct phy_provider *phy_provider;
> +	struct phy *generic_phy;
> +	int ret;
> +
> +	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
> +	if (!phy)
> +		return -ENOMEM;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	phy->mmio = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(phy->mmio))
> +		return PTR_ERR(phy->mmio);
> +
> +	generic_phy = devm_phy_create(dev, NULL, &qcom_ipq806x_sata_phy_ops,
> +				      NULL);
> +	if (IS_ERR(generic_phy)) {
> +		dev_err(dev, "%s: failed to create phy\n", __func__);
> +		return PTR_ERR(generic_phy);
> +	}
> +
> +	phy->dev = dev;
> +	phy_set_drvdata(generic_phy, phy);
> +	platform_set_drvdata(pdev, phy);
> +
> +	phy->cfg_clk = devm_clk_get(dev, "cfg");
> +	if (IS_ERR(phy->cfg_clk)) {
> +		dev_err(dev, "Failed to get sata cfg clock\n");
> +		return PTR_ERR(phy->cfg_clk);
> +	}
> +
> +	ret = clk_prepare_enable(phy->cfg_clk);
> +	if (ret)
> +		return ret;
> +
> +	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
> +	if (IS_ERR(phy_provider)) {
> +		clk_disable_unprepare(phy->cfg_clk);
> +		dev_err(dev, "%s: failed to register phy\n", __func__);
> +		return PTR_ERR(phy_provider);
> +	}
> +
> +	return 0;
> +}
> +
> +static int qcom_ipq806x_sata_phy_remove(struct platform_device *pdev)
> +{
> +	struct qcom_ipq806x_sata_phy *phy = platform_get_drvdata(pdev);
> +
> +	clk_disable_unprepare(phy->cfg_clk);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id qcom_ipq806x_sata_phy_of_match[] = {
> +	{ .compatible = "qcom,ipq806x-sata-phy" },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, qcom_ipq806x_sata_phy_of_match);
> +
> +static struct platform_driver qcom_ipq806x_sata_phy_driver = {
> +	.probe	= qcom_ipq806x_sata_phy_probe,
> +	.remove	= qcom_ipq806x_sata_phy_remove,
> +	.driver = {
> +		.name	= "qcom-ipq806x-sata-phy",
> +		.owner	= THIS_MODULE,
> +		.of_match_table	= qcom_ipq806x_sata_phy_of_match,
> +	}
> +};
> +module_platform_driver(qcom_ipq806x_sata_phy_driver);
> +
> +MODULE_DESCRIPTION("QCOM IPQ806x SATA PHY driver");
> +MODULE_LICENSE("GPL v2");
>