Re: [PATCH 8/9] ata: Add support for the Tegra124 SATA controller

[Bartlomiej Zolnierkiewicz <b.zolnierkie-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>]

Hi,

On Wednesday, June 04, 2014 02:32:38 PM Mikko Perttunen wrote:
> This adds support for the integrated AHCI-compliant Serial ATA
> controller present on the NVIDIA Tegra124 system-on-chip.
> 
> Signed-off-by: Mikko Perttunen <mperttunen-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
> ---
>  drivers/ata/Kconfig      |   9 ++
>  drivers/ata/Makefile     |   1 +
>  drivers/ata/ahci_tegra.c | 386 +++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 396 insertions(+)
>  create mode 100644 drivers/ata/ahci_tegra.c
> 
> diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
> index 7671dba..e65d400 100644
> --- a/drivers/ata/Kconfig
> +++ b/drivers/ata/Kconfig
> @@ -141,6 +141,15 @@ config AHCI_SUNXI
>  
>  	  If unsure, say N.
>  
> +config AHCI_TEGRA
> +	tristate "NVIDIA Tegra124 AHCI SATA support"
> +	depends on ARCH_TEGRA
> +	help
> +	  This option enables support for the NVIDIA Tegra124 SoC's
> +	  onboard AHCI SATA.
> +
> +	  If unsure, say N.
> +
>  config AHCI_XGENE
>  	tristate "APM X-Gene 6.0Gbps AHCI SATA host controller support"
>  	depends on PHY_XGENE
> diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
> index 5a02aee..ae41107 100644
> --- a/drivers/ata/Makefile
> +++ b/drivers/ata/Makefile
> @@ -15,6 +15,7 @@ obj-$(CONFIG_AHCI_IMX)		+= ahci_imx.o libahci.o libahci_platform.o
>  obj-$(CONFIG_AHCI_MVEBU)	+= ahci_mvebu.o libahci.o libahci_platform.o
>  obj-$(CONFIG_AHCI_SUNXI)	+= ahci_sunxi.o libahci.o libahci_platform.o
>  obj-$(CONFIG_AHCI_ST)		+= ahci_st.o libahci.o libahci_platform.o
> +obj-$(CONFIG_AHCI_TEGRA)	+= ahci_tegra.o libahci.o libahci_platform.o
>  obj-$(CONFIG_AHCI_XGENE)	+= ahci_xgene.o libahci.o libahci_platform.o
>  
>  # SFF w/ custom DMA
> diff --git a/drivers/ata/ahci_tegra.c b/drivers/ata/ahci_tegra.c
> new file mode 100644
> index 0000000..a10aac0
> --- /dev/null
> +++ b/drivers/ata/ahci_tegra.c
> @@ -0,0 +1,386 @@
> +/*
> + * drivers/ata/ahci_tegra.c
> + *
> + * Copyright (c) 2014, NVIDIA CORPORATION.  All rights reserved.
> + *
> + * Author:
> + *	Mikko Perttunen <mperttunen-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
> + *
> + * This software is licensed under the terms of the GNU General Public
> + * License version 2, as published by the Free Software Foundation, and
> + * may be copied, distributed, and modified under those terms.
> + *
> + * 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/ahci_platform.h>
> +#include <linux/reset.h>
> +#include <linux/errno.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/tegra-powergate.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/tegra-soc.h>
> +#include "ahci.h"
> +
> +#define SATA_CONFIGURATION_0				0x180
> +#define		SATA_CONFIGURATION_EN_FPCI		(1<<0)

minor nitpick: BIT() macro can be used here

> +#define SCFG_OFFSET					0x1000
> +
> +#define T_SATA0_CFG_1					0x04
> +#define		T_SATA0_CFG_1_IO_SPACE			(1<<0)
> +#define		T_SATA0_CFG_1_MEMORY_SPACE		(1<<1)
> +#define		T_SATA0_CFG_1_BUS_MASTER		(1<<2)
> +#define		T_SATA0_CFG_1_SERR			(1<<8)

ditto

> +#define T_SATA0_CFG_9					0x24
> +
> +#define SATA_FPCI_BAR5					0x94
> +
> +#define SATA_INTR_MASK					0x188
> +#define		SATA_INTR_MASK_IP_INT_MASK		(1<<16)

ditto

> +#define T_SATA0_AHCI_HBA_CAP_BKDR			0x300
> +
> +#define T_SATA0_BKDOOR_CC				0x4a4
> +
> +#define T_SATA0_CFG_SATA				0x54c
> +#define		T_SATA0_CFG_SATA_BACKDOOR_PROG_IF_EN	(1<<12)

ditto

> +#define T_SATA0_CFG_MISC				0x550
> +
> +#define T_SATA0_INDEX					0x680
> +
> +#define T_SATA0_CHX_PHY_CTRL1_GEN1			0x690
> +#define		T_SATA0_CHX_PHY_CTRL1_GEN1_TX_AMP_MASK	0xff
> +#define		T_SATA0_CHX_PHY_CTRL1_GEN1_TX_AMP_SHIFT	0
> +#define		T_SATA0_CHX_PHY_CTRL1_GEN1_TX_PEAK_MASK	(0xff<<8)
> +#define		T_SATA0_CHX_PHY_CTRL1_GEN1_TX_PEAK_SHIFT 8
> +
> +#define T_SATA0_CHX_PHY_CTRL1_GEN2			0x694
> +#define		T_SATA0_CHX_PHY_CTRL1_GEN2_TX_AMP_MASK	0xff
> +#define		T_SATA0_CHX_PHY_CTRL1_GEN2_TX_AMP_SHIFT	0
> +#define		T_SATA0_CHX_PHY_CTRL1_GEN2_TX_PEAK_MASK	(0xff<<12)
> +#define		T_SATA0_CHX_PHY_CTRL1_GEN2_TX_PEAK_SHIFT 12
> +
> +#define T_SATA0_CHX_PHY_CTRL2				0x69c
> +#define		T_SATA0_CHX_PHY_CTRL2_CDR_CNTL_GEN1	0x23
> +
> +#define T_SATA0_CHX_PHY_CTRL11				0x6d0
> +#define		T_SATA0_CHX_PHY_CTRL11_GEN2_RX_EQ	(0x2800<<16)
> +
> +struct sata_pad_calibration {
> +	u8 gen1_tx_amp, gen1_tx_peak, gen2_tx_amp, gen2_tx_peak;
> +};
> +
> +static const struct sata_pad_calibration tegra124_pad_calibration[] = {
> +	{0x18, 0x04, 0x18, 0x0a},
> +	{0x0e, 0x04, 0x14, 0x0a},
> +	{0x0e, 0x07, 0x1a, 0x0e},
> +	{0x14, 0x0e, 0x1a, 0x0e},
> +};
> +
> +struct tegra_ahci_priv {
> +	struct platform_device *pdev;
> +	void __iomem *sata_regs;
> +	struct reset_control *sata_rst;
> +	struct reset_control *sata_oob_rst;
> +	struct reset_control *sata_cold_rst;
> +	struct regulator_bulk_data supplies[3];
> +};
> +
> +static inline void sata_writel(struct tegra_ahci_priv *tegra, u32 value,
> +				 unsigned long offset)
> +{
> +	writel(value, tegra->sata_regs + offset);
> +}
> +
> +static inline u32 sata_readl(struct tegra_ahci_priv *tegra,
> +				unsigned long offset)
> +{
> +	return readl(tegra->sata_regs + offset);
> +}

sata_writel() and sata_read() static inlines don't seem to add any value.

Can they be removed?

> +static int tegra_ahci_power_on(struct ahci_host_priv *hpriv)
> +{
> +	struct tegra_ahci_priv *tegra = hpriv->plat_data;
> +	int ret;
> +
> +	ret = regulator_bulk_enable(ARRAY_SIZE(tegra->supplies),
> +				    tegra->supplies);
> +	if (ret)
> +		return ret;
> +
> +	reset_control_assert(tegra->sata_rst);
> +	reset_control_assert(tegra->sata_oob_rst);
> +	reset_control_assert(tegra->sata_cold_rst);
> +
> +	ret = tegra_powergate_power_on(TEGRA_POWERGATE_SATA);
> +	if (ret)
> +		goto reset_deassert;

Shouldn't the driver disable regulators on failure?

[ tegra_ahci_power_off() does it so it should also be done here. ]

> +	/* Enable clocks */
> +	ret = ahci_platform_enable_resources(hpriv);
> +	if (ret)
> +		goto power_off;
> +
> +	udelay(10);
> +
> +	ret = tegra_powergate_remove_clamping(TEGRA_POWERGATE_SATA);
> +	if (ret)
> +		goto disable_resources;
> +
> +	udelay(10);
> +
> +	reset_control_deassert(tegra->sata_cold_rst);
> +	reset_control_deassert(tegra->sata_oob_rst);
> +	reset_control_deassert(tegra->sata_rst);
> +
> +	return 0;
> +
> +disable_resources:
> +	ahci_platform_disable_resources(hpriv);
> +
> +power_off:
> +	tegra_powergate_power_off(TEGRA_POWERGATE_SATA);
> +
> +reset_deassert:
> +	reset_control_deassert(tegra->sata_cold_rst);
> +	reset_control_deassert(tegra->sata_oob_rst);
> +	reset_control_deassert(tegra->sata_rst);

reset_control_deassert() sequence is can be moved to separate static
inline helper to prevent code duplication.

> +	return ret;
> +}
> +
> +static void tegra_ahci_power_off(struct ahci_host_priv *hpriv)
> +{
> +	struct tegra_ahci_priv *tegra = hpriv->plat_data;
> +
> +	reset_control_assert(tegra->sata_rst);
> +	reset_control_assert(tegra->sata_oob_rst);
> +	reset_control_assert(tegra->sata_cold_rst);

Same for reset_control_assert() sequence.

> +	ahci_platform_disable_resources(hpriv);
> +
> +	tegra_powergate_power_off(TEGRA_POWERGATE_SATA);
> +
> +	reset_control_deassert(tegra->sata_cold_rst);
> +	reset_control_deassert(tegra->sata_oob_rst);
> +	reset_control_deassert(tegra->sata_rst);
> +
> +	regulator_bulk_disable(ARRAY_SIZE(tegra->supplies), tegra->supplies);
> +}
> +
> +static int tegra_ahci_controller_init(struct ahci_host_priv *hpriv)
> +{
> +	struct tegra_ahci_priv *tegra = hpriv->plat_data;
> +	int ret;
> +	unsigned int val;
> +	struct sata_pad_calibration calib;
> +
> +	ret = tegra_ahci_power_on(hpriv);
> +	if (ret) {
> +		dev_err(&tegra->pdev->dev,
> +			"failed to power on ahci controller: %d\n", ret);
> +		return ret;
> +	}
> +
> +	val = sata_readl(tegra, SATA_CONFIGURATION_0);
> +	val |= SATA_CONFIGURATION_EN_FPCI;
> +	sata_writel(tegra, val, SATA_CONFIGURATION_0);
> +
> +	/* Pad calibration */
> +
> +	ret = tegra_fuse_readl(0x224, &val);
> +	if (ret) {
> +		dev_err(&tegra->pdev->dev,
> +			"failed to read sata calibration fuse: %d\n", ret);
> +		return ret;
> +	}
> +
> +	calib = tegra124_pad_calibration[val];
> +
> +	sata_writel(tegra, (1 << 0), SCFG_OFFSET + T_SATA0_INDEX);
> +
> +	val = sata_readl(tegra, SCFG_OFFSET + T_SATA0_CHX_PHY_CTRL1_GEN1);
> +	val &= ~T_SATA0_CHX_PHY_CTRL1_GEN1_TX_AMP_MASK;
> +	val &= ~T_SATA0_CHX_PHY_CTRL1_GEN1_TX_PEAK_MASK;
> +	val |= calib.gen1_tx_amp <<
> +			T_SATA0_CHX_PHY_CTRL1_GEN1_TX_AMP_SHIFT;
> +	val |= calib.gen1_tx_peak <<
> +			T_SATA0_CHX_PHY_CTRL1_GEN1_TX_PEAK_SHIFT;
> +	sata_writel(tegra, val, SCFG_OFFSET + T_SATA0_CHX_PHY_CTRL1_GEN1);
> +
> +	val = sata_readl(tegra, SCFG_OFFSET + T_SATA0_CHX_PHY_CTRL1_GEN2);
> +	val &= ~T_SATA0_CHX_PHY_CTRL1_GEN2_TX_AMP_MASK;
> +	val &= ~T_SATA0_CHX_PHY_CTRL1_GEN2_TX_PEAK_MASK;
> +	val |= calib.gen2_tx_amp <<
> +			T_SATA0_CHX_PHY_CTRL1_GEN1_TX_AMP_SHIFT;
> +	val |= calib.gen2_tx_peak <<
> +			T_SATA0_CHX_PHY_CTRL1_GEN1_TX_PEAK_SHIFT;
> +	sata_writel(tegra, val, SCFG_OFFSET + T_SATA0_CHX_PHY_CTRL1_GEN2);
> +
> +	sata_writel(tegra, T_SATA0_CHX_PHY_CTRL11_GEN2_RX_EQ,
> +		    SCFG_OFFSET + T_SATA0_CHX_PHY_CTRL11);
> +	sata_writel(tegra, T_SATA0_CHX_PHY_CTRL2_CDR_CNTL_GEN1,
> +		    SCFG_OFFSET + T_SATA0_CHX_PHY_CTRL2);
> +
> +	sata_writel(tegra, 0, SCFG_OFFSET + T_SATA0_INDEX);
> +
> +	/* Program controller device ID */
> +
> +	val = sata_readl(tegra, SCFG_OFFSET + T_SATA0_CFG_SATA);
> +	val |= T_SATA0_CFG_SATA_BACKDOOR_PROG_IF_EN;
> +	sata_writel(tegra, val, SCFG_OFFSET + T_SATA0_CFG_SATA);
> +
> +	sata_writel(tegra, 0x01060100, SCFG_OFFSET + T_SATA0_BKDOOR_CC);
> +
> +	val = sata_readl(tegra, SCFG_OFFSET + T_SATA0_CFG_SATA);
> +	val &= ~T_SATA0_CFG_SATA_BACKDOOR_PROG_IF_EN;
> +	sata_writel(tegra, val, SCFG_OFFSET + T_SATA0_CFG_SATA);
> +
> +	/* Enable IO & memory access, bus master mode */
> +
> +	val = sata_readl(tegra, SCFG_OFFSET + T_SATA0_CFG_1);
> +	val |= T_SATA0_CFG_1_IO_SPACE | T_SATA0_CFG_1_MEMORY_SPACE |
> +		T_SATA0_CFG_1_BUS_MASTER | T_SATA0_CFG_1_SERR;
> +	sata_writel(tegra, val, SCFG_OFFSET + T_SATA0_CFG_1);
> +
> +	/* Program SATA MMIO */
> +
> +	sata_writel(tegra, 0x10000 << 4, SATA_FPCI_BAR5);
> +	sata_writel(tegra, 0x08000 << 13, SCFG_OFFSET + T_SATA0_CFG_9);
> +
> +	/* Unmask SATA interrupts */
> +
> +	val = sata_readl(tegra, SATA_INTR_MASK);
> +	val |= SATA_INTR_MASK_IP_INT_MASK;
> +	sata_writel(tegra, val, SATA_INTR_MASK);
> +
> +	return 0;
> +}
> +
> +static void tegra_ahci_controller_deinit(struct ahci_host_priv *hpriv)
> +{
> +	tegra_ahci_power_off(hpriv);
> +}
> +
> +static void tegra_ahci_host_stop(struct ata_host *host)
> +{
> +	struct ahci_host_priv *hpriv = host->private_data;
> +
> +	tegra_ahci_controller_deinit(hpriv);
> +}
> +
> +static struct ata_port_operations ahci_tegra_port_ops = {
> +	.inherits	= &ahci_platform_ops,
> +	.host_stop	= tegra_ahci_host_stop,
> +};
> +
> +static const struct ata_port_info ahci_tegra_port_info = {
> +	.flags		= AHCI_FLAG_COMMON,
> +	.pio_mask	= ATA_PIO4,
> +	.udma_mask	= ATA_UDMA6,
> +	.port_ops	= &ahci_tegra_port_ops,
> +};
> +
> +static const struct of_device_id tegra_ahci_of_match[] = {
> +	{ .compatible = "nvidia,tegra124-ahci" },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, tegra_ahci_of_match);
> +
> +static int tegra_ahci_probe(struct platform_device *pdev)
> +{
> +	const struct of_device_id *match;
> +	struct ahci_host_priv *hpriv;
> +	struct tegra_ahci_priv *tegra;
> +	int ret;
> +
> +	match = of_match_device(tegra_ahci_of_match, &pdev->dev);
> +	if (!match)
> +		return -EINVAL;
> +
> +	hpriv = ahci_platform_get_resources(pdev);
> +	if (IS_ERR(hpriv))
> +		return PTR_ERR(hpriv);
> +
> +	tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL);
> +	if (!tegra)
> +		return -ENOMEM;
> +
> +	hpriv->plat_data = tegra;
> +
> +	tegra->pdev = pdev;
> +
> +	tegra->sata_regs = devm_ioremap_resource(&pdev->dev,
> +		platform_get_resource(pdev, IORESOURCE_MEM, 1));
> +	if (IS_ERR(tegra->sata_regs)) {
> +		dev_err(&pdev->dev, "Failed to get SATA IO memory");
> +		return PTR_ERR(tegra->sata_regs);
> +	}
> +
> +	tegra->sata_rst = devm_reset_control_get(&pdev->dev, "sata");
> +	if (IS_ERR(tegra->sata_rst)) {
> +		dev_err(&pdev->dev, "Failed to get sata reset");
> +		return PTR_ERR(tegra->sata_rst);
> +	}
> +
> +	tegra->sata_oob_rst = devm_reset_control_get(&pdev->dev, "sata-oob");
> +	if (IS_ERR(tegra->sata_oob_rst)) {
> +		dev_err(&pdev->dev, "Failed to get sata-oob reset");
> +		return PTR_ERR(tegra->sata_oob_rst);
> +	}
> +
> +	tegra->sata_cold_rst = devm_reset_control_get(&pdev->dev, "sata-cold");
> +	if (IS_ERR(tegra->sata_cold_rst)) {
> +		dev_err(&pdev->dev, "Failed to get sata-cold reset");
> +		return PTR_ERR(tegra->sata_cold_rst);
> +	}
> +
> +	tegra->supplies[0].supply = "avdd";
> +	tegra->supplies[1].supply = "hvdd";
> +	tegra->supplies[2].supply = "vddio";
> +
> +	ret = devm_regulator_bulk_get(&pdev->dev, ARRAY_SIZE(tegra->supplies),
> +					tegra->supplies);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to get regulators");
> +		return ret;
> +	}
> +
> +	ret = tegra_ahci_controller_init(hpriv);
> +	if (ret)
> +		return ret;
> +
> +	ret = ahci_platform_init_host(pdev, hpriv, &ahci_tegra_port_info,
> +				      0, 0, 0);
> +	if (ret) {
> +		tegra_ahci_controller_deinit(hpriv);
> +		return ret;
> +	}
> +
> +	return 0;
> +};
> +
> +static struct platform_driver tegra_ahci_driver = {
> +	.probe = tegra_ahci_probe,
> +	.remove = ata_platform_remove_one,
> +	.driver = {
> +		.name = "tegra-ahci",
> +		.owner = THIS_MODULE,
> +		.of_match_table = tegra_ahci_of_match,
> +	},

This driver lacks PM suspend/resume support.  I assume that
the Tegra124 platform also doesn't support suspend/resume yet
(if so a comment in the driver code about this would be useful),
otherwise the driver should be fixed.

> +};
> +module_platform_driver(tegra_ahci_driver);
> +
> +MODULE_AUTHOR("Mikko Perttunen <mperttunen-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>");
> +MODULE_DESCRIPTION("Tegra124 AHCI SATA driver");
> +MODULE_LICENSE("GPL v2");

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics