Re: [PATCH v6 1/7] phy: add a driver for the Berlin SATA PHY

[Varka Bhadram <varkabhadram@gmail.com>]

On 06/24/2014 05:30 PM, Kishon Vijay Abraham I wrote:
> Hi,
>
> On Monday 16 June 2014 03:56 PM, Antoine Ténart wrote:
>> The Berlin SoC has a two SATA ports. Add a PHY driver to handle them.
>>
>> The mode selection can let us think this PHY can be configured to fit
>> other purposes. But there are reasons to think the SATA mode will be
>> the only one usable: the PHY registers are only accessible indirectly
>> through two registers in the SATA range, the PHY seems to be integrated
>> and no information tells us the contrary. For these reasons, make the
>> driver a SATA PHY driver.
>>
>> Signed-off-by: Antoine Ténart <antoine.tenart@free-electrons.com>
>> ---
>>   drivers/phy/Kconfig           |   7 ++
>>   drivers/phy/Makefile          |   1 +
>>   drivers/phy/phy-berlin-sata.c | 232 ++++++++++++++++++++++++++++++++++++++++++
>>   3 files changed, 240 insertions(+)
>>   create mode 100644 drivers/phy/phy-berlin-sata.c
>>
>> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
>> index 16a2f067c242..365ad3651e1c 100644
>> --- a/drivers/phy/Kconfig
>> +++ b/drivers/phy/Kconfig
>> @@ -15,6 +15,13 @@ config GENERIC_PHY
>>   	  phy users can obtain reference to the PHY. All the users of this
>>   	  framework should select this config.
>>   
>> +config PHY_BERLIN_SATA
>> +	tristate "Marvell Berlin SATA PHY driver"
>> +	depends on ARCH_BERLIN && OF
>> +	select GENERIC_PHY
>> +	help
>> +	  Enable this to support the SATA PHY on Marvell Berlin SoCs.
>> +
>>   config PHY_EXYNOS_MIPI_VIDEO
>>   	tristate "S5P/EXYNOS SoC series MIPI CSI-2/DSI PHY driver"
>>   	depends on HAS_IOMEM
>> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
>> index b4f1d5770601..a137a2e23218 100644
>> --- a/drivers/phy/Makefile
>> +++ b/drivers/phy/Makefile
>> @@ -3,6 +3,7 @@
>>   #
>>   
>>   obj-$(CONFIG_GENERIC_PHY)		+= phy-core.o
>> +obj-$(CONFIG_PHY_BERLIN_SATA)		+= phy-berlin-sata.o
>>   obj-$(CONFIG_BCM_KONA_USB2_PHY)		+= phy-bcm-kona-usb2.o
>>   obj-$(CONFIG_PHY_EXYNOS_DP_VIDEO)	+= phy-exynos-dp-video.o
>>   obj-$(CONFIG_PHY_EXYNOS_MIPI_VIDEO)	+= phy-exynos-mipi-video.o
>> diff --git a/drivers/phy/phy-berlin-sata.c b/drivers/phy/phy-berlin-sata.c
>> new file mode 100644
>> index 000000000000..907897a02672
>> --- /dev/null
>> +++ b/drivers/phy/phy-berlin-sata.c
>> @@ -0,0 +1,232 @@
>> +/*
>> + * Marvell Berlin SATA PHY driver
>> + *
>> + * Copyright (C) 2014 Marvell Technology Group Ltd.
>> + *
>> + * Antoine Ténart <antoine.tenart@free-electrons.com>
>> + *
>> + * This file is licensed under the terms of the GNU General Public
>> + * License version 2. This program is licensed "as is" without any
>> + * warranty of any kind, whether express or implied.
>> + */
>> +
>> +#include <linux/module.h>
>> +#include <linux/phy/phy.h>
>> +#include <linux/io.h>
>> +#include <linux/platform_device.h>
>> +
>> +#define HOST_VSA_ADDR		0x0
>> +#define HOST_VSA_DATA		0x4
>> +#define PORT_VSR_ADDR		0x78
>> +#define PORT_VSR_DATA		0x7c
>> +#define PORT_SCR_CTL		0x2c
>> +
>> +#define CONTROL_REGISTER	0x0
>> +#define MBUS_SIZE_CONTROL	0x4
>> +
>> +#define POWER_DOWN_PHY0			BIT(6)
>> +#define POWER_DOWN_PHY1			BIT(14)
>> +#define MBUS_WRITE_REQUEST_SIZE_128	(BIT(2) << 16)
>> +#define MBUS_READ_REQUEST_SIZE_128	(BIT(2) << 19)
>> +
>> +#define PHY_BASE		0x200
>> +
>> +/* register 0x01 */
>> +#define REF_FREF_SEL_25		BIT(0)
>> +#define PHY_MODE_SATA		(0x0 << 5)
>> +
>> +/* register 0x02 */
>> +#define USE_MAX_PLL_RATE	BIT(12)
>> +
>> +/* register 0x23 */
>> +#define DATA_BIT_WIDTH_10	(0x0 << 10)
>> +#define DATA_BIT_WIDTH_20	(0x1 << 10)
>> +#define DATA_BIT_WIDTH_40	(0x2 << 10)
>> +
>> +/* register 0x25 */
>> +#define PHY_GEN_MAX_1_5		(0x0 << 10)
>> +#define PHY_GEN_MAX_3_0		(0x1 << 10)
>> +#define PHY_GEN_MAX_6_0		(0x2 << 10)
>> +
>> +#define BERLIN_SATA_PHY_NB	2
> multi-phy PHY providers should be modelled so that each individual
> PHY is made as sub-node of the PHY provider. Please refer [1] for the
> discussion on this.
>
> [1] -> https://lkml.org/lkml/2014/6/24/131
>
> Thanks
> Kishon
>> +
>> +#define to_berlin_sata_phy_priv(desc)	\
>> +	container_of((desc), struct phy_berlin_priv, phys[(desc)->index])
>> +
>> +struct phy_berlin_desc {
>> +	struct phy	*phy;
>> +	u32		val;
>> +	unsigned	index;
>> +};
>> +
>> +struct phy_berlin_priv {
>> +	void __iomem		*base;
>> +	spinlock_t		lock;
>> +	struct phy_berlin_desc	phys[BERLIN_SATA_PHY_NB];
>> +};
>> +
>> +static inline void phy_berlin_sata_reg_setbits(void __iomem *ctrl_reg, u32 reg,
>> +					       u32 mask, u32 val)
>> +{
>> +	u32 regval;
>> +
>> +	/* select register */
>> +	writel(PHY_BASE + reg, ctrl_reg + PORT_VSR_ADDR);
>> +
>> +	/* set bits */
>> +	regval = readl(ctrl_reg + PORT_VSR_DATA);
>> +	regval &= ~mask;
>> +	regval |= val;
>> +	writel(regval, ctrl_reg + PORT_VSR_DATA);
>> +}
>> +
>> +static int phy_berlin_sata_power_on(struct phy *phy)
>> +{
>> +	struct phy_berlin_desc *desc = phy_get_drvdata(phy);
>> +	struct phy_berlin_priv *priv = to_berlin_sata_phy_priv(desc);
>> +	void __iomem *ctrl_reg = priv->base + 0x60 + (desc->index * 0x80);
>> +	int ret = 0;
>> +	u32 regval;
>> +
>> +	spin_lock(&priv->lock);
>> +
>> +	/* Power on PHY */
>> +	writel(CONTROL_REGISTER, priv->base + HOST_VSA_ADDR);
>> +	regval = readl(priv->base + HOST_VSA_DATA);
>> +	regval &= ~(desc->val);
>> +	writel(regval, priv->base + HOST_VSA_DATA);
>> +
>> +	/* Configure MBus */
>> +	writel(MBUS_SIZE_CONTROL, priv->base + HOST_VSA_ADDR);
>> +	regval = readl(priv->base + HOST_VSA_DATA);
>> +	regval |= MBUS_WRITE_REQUEST_SIZE_128 | MBUS_READ_REQUEST_SIZE_128;
>> +	writel(regval, priv->base + HOST_VSA_DATA);
>> +
>> +	/* set PHY mode and ref freq to 25 MHz */
>> +	phy_berlin_sata_reg_setbits(ctrl_reg, 0x1, 0xff,
>> +				    REF_FREF_SEL_25 | PHY_MODE_SATA);
>> +
>> +	/* set PHY up to 6 Gbps */
>> +	phy_berlin_sata_reg_setbits(ctrl_reg, 0x25, 0xc00, PHY_GEN_MAX_6_0);
>> +
>> +	/* set 40 bits width */
>> +	phy_berlin_sata_reg_setbits(ctrl_reg, 0x23,  0xc00, DATA_BIT_WIDTH_40);
>> +
>> +	/* use max pll rate */
>> +	phy_berlin_sata_reg_setbits(ctrl_reg, 0x2, 0x0, USE_MAX_PLL_RATE);
>> +
>> +	/* set the controller speed */
>> +	writel(0x31, ctrl_reg + PORT_SCR_CTL);
>> +
>> +	spin_unlock(&priv->lock);
>> +
>> +	return ret;
>> +}
>> +
>> +static int phy_berlin_sata_power_off(struct phy *phy)
>> +{
>> +	struct phy_berlin_desc *desc = phy_get_drvdata(phy);
>> +	struct phy_berlin_priv *priv = to_berlin_sata_phy_priv(desc);
>> +	u32 regval;
>> +
>> +	spin_lock(&priv->lock);
>> +
>> +	/* Power down PHY */
>> +	writel(CONTROL_REGISTER, priv->base + HOST_VSA_ADDR);
>> +	regval = readl(priv->base + HOST_VSA_DATA);
>> +	regval |= desc->val;
>> +	writel(regval, priv->base + HOST_VSA_DATA);
>> +
>> +	spin_unlock(&priv->lock);
>> +
>> +	return 0;
>> +}
>> +
>> +static struct phy *phy_berlin_sata_phy_xlate(struct device *dev,
>> +					     struct of_phandle_args *args)

Indent the function properly like this:
static struct phy *phy_berlin_sata_phy_xlate(struct device *dev,
					     struct of_phandle_args *args)

check with checkpatch.pl script

>> +{
>> +	struct phy_berlin_priv *priv = dev_get_drvdata(dev);
>> +
>> +	if (WARN_ON(args->args[0] >= BERLIN_SATA_PHY_NB))
>> +		return ERR_PTR(-ENODEV);
>> +
>> +	return priv->phys[args->args[0]].phy;
>> +}
>> +
>> +static struct phy_ops phy_berlin_sata_ops = {
>> +	.power_on	= phy_berlin_sata_power_on,
>> +	.power_off	= phy_berlin_sata_power_off,
>> +	.owner		= THIS_MODULE,
>> +};
>> +
>> +static u32 phy_berlin_power_down_bits[] = {
>> +	POWER_DOWN_PHY0,
>> +	POWER_DOWN_PHY1,
>> +};
>> +
>> +static int phy_berlin_sata_probe(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct phy *phy;
>> +	struct phy_provider *phy_provider;
>> +	struct phy_berlin_priv *priv;
>> +	struct resource *res;
>> +	int i;
>> +
>> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
>> +	if (!priv)
>> +		return -ENOMEM;
>> +
>> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> +	if (!res)
>> +		return -EINVAL;
>> +
>> +	priv->base = devm_ioremap(dev, res->start, resource_size(res));
>> +	if (!priv->base)
>> +		return -ENOMEM;
>> +
>> +	dev_set_drvdata(dev, priv);
>> +	spin_lock_init(&priv->lock);
>> +
>> +	for (i = 0; i < BERLIN_SATA_PHY_NB; i++) {
>> +		phy = devm_phy_create(dev, &phy_berlin_sata_ops, NULL);
>> +		if (IS_ERR(phy)) {
>> +			dev_err(dev, "failed to create PHY %d\n", i);
>> +			return PTR_ERR(phy);
>> +		}
>> +
>> +		priv->phys[i].phy = phy;
>> +		priv->phys[i].val = phy_berlin_power_down_bits[i];
>> +		priv->phys[i].index = i;
>> +		phy_set_drvdata(phy, &priv->phys[i]);
>> +
>> +		/* Make sure the PHY is off */
>> +		phy_berlin_sata_power_off(phy);
>> +	}
>> +
>> +	phy_provider =
>> +		devm_of_phy_provider_register(dev, phy_berlin_sata_phy_xlate);
>> +	if (IS_ERR(phy_provider))
>> +		return PTR_ERR(phy_provider);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct of_device_id phy_berlin_sata_of_match[] = {
>> +	{ .compatible = "marvell,berlin-sata-phy" },
>> +	{ },
>> +};
>> +
>> +static struct platform_driver phy_berlin_sata_driver = {
>> +	.probe	= phy_berlin_sata_probe,
>> +	.driver	= {
>> +		.name		= "phy-berlin-sata",
>> +		.owner		= THIS_MODULE,
>> +		.of_match_table	= phy_berlin_sata_of_match,

use of_match_ptr for of_match_table

>> +	},
>> +};
>> +module_platform_driver(phy_berlin_sata_driver);
>> +
>> +MODULE_DESCRIPTION("Marvell Berlin SATA PHY driver");
>> +MODULE_AUTHOR("Antoine Ténart <antoine.tenart@free-electrons.com>");
>> +MODULE_LICENSE("GPL v2");
>>
> --
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