Re: [PATCH 1/6] ata: ahci: add AHCI support for Berlin SoCs

Bartlomiej Zolnierkiewicz
2014-04-22T16:55:13Z

Hi,

On Tuesday, April 22, 2014 05:38:20 PM Antoine Ténart wrote:
> Add support for the Berlin SoCs AHCI SATA controller allowing to
> interface with devices like external hard drives.
>
> Signed-off-by: Antoine Ténart <antoine.tenart@free-electrons.com>
> ---
> drivers/ata/Kconfig | 9 +++
> drivers/ata/Makefile | 1 +
> drivers/ata/ahci_berlin.c | 175 ++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 185 insertions(+)
> create mode 100644 drivers/ata/ahci_berlin.c
>
> diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
> index 20e03a7eb8b4..c985dfcd5a6c 100644
> --- a/drivers/ata/Kconfig
> +++ b/drivers/ata/Kconfig
> @@ -97,6 +97,15 @@ config SATA_AHCI_PLATFORM
>
> If unsure, say N.
>
> +config AHCI_BERLIN
> + tristate "Marvell Berlin AHCI SATA support"
> + depends on ARCH_BERLIN
> + help
> + This option enables support for the Marvell Berlin SoC's
> + onboard AHCI SATA.
> +
> + If unsure, say N.
> +
> config AHCI_DA850
> tristate "DaVinci DA850 AHCI SATA support"
> depends on ARCH_DAVINCI_DA850
> diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
> index 44c8016e565c..7fb78d1e0a44 100644
> --- a/drivers/ata/Makefile
> +++ b/drivers/ata/Makefile
> @@ -10,6 +10,7 @@ obj-$(CONFIG_SATA_INIC162X) += sata_inic162x.o
> obj-$(CONFIG_SATA_SIL24) += sata_sil24.o
> obj-$(CONFIG_SATA_DWC) += sata_dwc_460ex.o
> obj-$(CONFIG_SATA_HIGHBANK) += sata_highbank.o libahci.o
> +obj-$(CONFIG_AHCI_BERLIN) += ahci_berlin.o libahci.o libahci_platform.o
> obj-$(CONFIG_AHCI_DA850) += ahci_da850.o libahci.o libahci_platform.o
> obj-$(CONFIG_AHCI_IMX) += ahci_imx.o libahci.o libahci_platform.o
> obj-$(CONFIG_AHCI_SUNXI) += ahci_sunxi.o libahci.o libahci_platform.o
> diff --git a/drivers/ata/ahci_berlin.c b/drivers/ata/ahci_berlin.c
> new file mode 100644
> index 000000000000..cf1c9d3b9d18
> --- /dev/null
> +++ b/drivers/ata/ahci_berlin.c
> @@ -0,0 +1,175 @@
> +/*
> + * Marvell Berlin AHCI SATA platform 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/ahci_platform.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +
> +#include "ahci.h"
> +
> +#define PORT_VSR_ADDR 0x78
> +#define PORT_VSR_DATA 0x7C
> +#define HOST_VSA_ADDR 0xA0
> +#define HOST_VSA_DATA 0xA4
> +
> +static inline void ahci_berlin_reg_setbits(void __iomem *reg, u32 val)
> +{
> + u32 regval;
> +
> + regval = readl(reg);
> + regval |= val;
> + writel(regval, reg);
> +}
> +
> +static inline void ahci_berlin_reg_set(void __iomem *reg, u32 val)
> +{
> + writel(val, reg);
> +}
> +
> +static inline void ahci_berlin_reg_clear_set(void __iomem *reg, u32 clear_val,
> + u32 set_val)
> +{
> + u32 regval;
> +
> + regval = readl(reg);
> + regval &= ~(clear_val);
> + regval |= set_val;
> + writel(regval, reg);
> +}
> +
> +static void ahci_berlin_init(void __iomem *mmio)
> +{
> + /* interface select */
> + ahci_berlin_reg_set(mmio + HOST_VSA_ADDR, BIT(2));
> + ahci_berlin_reg_set(mmio + HOST_VSA_ADDR,
> + BIT(21) | BIT(18) | BIT(5) | BIT(4) | BIT(2));
> +
> +}
> +
> +static void ahci_berlin_port_init(void __iomem *mmio, unsigned int ports)
> +{
> + int p;
> +
> + /* power down pll */
> + ahci_berlin_reg_set(mmio + HOST_VSA_ADDR, 0x0);
> + ahci_berlin_reg_setbits(mmio + HOST_VSA_DATA, BIT(6));
> +
> + for (p = 0; p < ports; p++) {
> + /* port control register */
> + void __iomem *ctrl_reg = mmio + 0x100 + (p * 0x80);
> +
> + /* set PHY mode to SATA, ref freq to 25 MHz */
> + ahci_berlin_reg_set(ctrl_reg + PORT_VSR_ADDR, 0x201);
> + ahci_berlin_reg_clear_set(ctrl_reg + PORT_VSR_DATA,
> + 0xff, BIT(0));
> +
> + /* set PHY up to 6 Gbps */
> + ahci_berlin_reg_set(ctrl_reg + PORT_VSR_ADDR, 0x225);
> + ahci_berlin_reg_clear_set(ctrl_reg + PORT_VSR_DATA,
> + BIT(11) | BIT(10), BIT(11));
> +
> + /* set SEL_BITS to 40 bit */
> + ahci_berlin_reg_set(ctrl_reg + PORT_VSR_ADDR, 0x223);
> + ahci_berlin_reg_clear_set(ctrl_reg + PORT_VSR_DATA,
> + BIT(11) | BIT(10), BIT(11));
> +
> + /* use max pll rate */
> + ahci_berlin_reg_set(ctrl_reg + PORT_VSR_ADDR, 0x202);
> + ahci_berlin_reg_setbits(ctrl_reg + PORT_VSR_DATA, BIT(12));
> +
> + /* CT timing fix */
> + ahci_berlin_reg_set(ctrl_reg + PORT_VSR_ADDR, BIT(6) | BIT(1));
> + ahci_berlin_reg_set(ctrl_reg + PORT_VSR_ADDR,
> + BIT(15) | BIT(13) | BIT(12) | BIT(11) |
> + BIT(10) | BIT(2) | BIT(1));
> +
> + /* set the controller speed */
> + ahci_berlin_reg_set(ctrl_reg + PORT_SCR_CTL,
> + BIT(6) | BIT(5) | BIT(0));
> + }
> +
> + /* power up pll */
> + ahci_berlin_reg_set(mmio + HOST_VSA_ADDR, 0x0);
> + ahci_berlin_reg_clear_set(mmio + HOST_VSA_DATA, BIT(6), 0x0);
> +}
> +
> +static const struct ata_port_info ahci_berlin_port_info = {
> + .flags = AHCI_FLAG_COMMON | ATA_FLAG_NCQ,
> + .pio_mask = ATA_PIO4,
> + .udma_mask = ATA_UDMA6,
> + .port_ops = &ahci_platform_ops,
> +};
> +
> +static int ahci_berlin_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *np = dev->of_node;
> + struct ahci_host_priv *hpriv;
> + int ret, nports, force_map = 0;
> +
> + hpriv = ahci_platform_get_resources(pdev);
> + if (IS_ERR(hpriv)) {
> + dev_err(dev, "cannot get AHCI resources\n");
> + return PTR_ERR(hpriv);
> + }
> +
> + ret = ahci_platform_enable_resources(hpriv);
> + if (ret) {
> + dev_err(dev, "cannot enable resources: %d\n", ret);
> + return ret;
> + }
> +
> + nports = readl(hpriv->mmio + HOST_PORTS_IMPL);
> +
> + /* force_map is modified only if the property is found */
> + of_property_read_u32(np, "marvell,force-port-map", &force_map);
> + if (force_map)
> + nports = force_map;
> +
> + ahci_berlin_init(hpriv->mmio);
> + ahci_berlin_port_init(hpriv->mmio, nports);
> +
> + ret = ahci_platform_init_host(pdev, hpriv, &ahci_berlin_port_info,
> + force_map, 0);
> + if (ret) {
> + dev_err(dev, "host init failed: %d\n", ret);
> + goto disable_resources;
> + }
> +
> + return 0;
> +
> +disable_resources:
> + ahci_platform_disable_resources(hpriv);
> + return ret;
> +}
> +
> +static const struct of_device_id ahci_berlin_of_match[] = {
> + { .compatible = "marvell,berlin-ahci" },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, ahci_berlin_of_match);
> +
> +static struct platform_driver ahci_berlin_driver = {
> + .probe = ahci_berlin_probe,
> + .remove = ata_platform_remove_one,
> + .driver = {
> + .name = "ahci-berlin",
> + .owner = THIS_MODULE,
> + .of_match_table = ahci_berlin_of_match,

Please add a comment explaining lack of power management support
(i.e. that your platform doesn't have PM support implemented yet).

Otherwise the driver looks fine.

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

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