[PATCH v2 3/3] ata: add new-style AHCI platform driver for DaVinci DA850 AHCI controller

From: Bartlomiej Zolnierkiewicz
Date: Thu Mar 20 2014 - 14:28:04 EST


Add the new ahci_da850 host driver and remove the deprecated
ahci_platform_data platform code.

Please note that the new driver doesn't have the superfluous
clock control code as clock is already handled by the generic
AHCI platform library code.

Cc: Sekhar Nori <nsekhar@xxxxxx>
Cc: Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx>
Cc: Hans de Goede <hdegoede@xxxxxxxxxx>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
---
v2:
- dropped the experimental tag from the config option help
- fixed SYSCFG1 memory resource handling
- hardcoded the multiplier data and added a note about it
- used readl()/writel() instead of __raw_readl()/__raw_writel()
- dropped the superflous clock control
- cleaned up da850_sata_init()
- changed the platform device name and removed the platform ids table
- removed the deprecated ahci_platform_data platform code
- updated the patch description

arch/arm/mach-davinci/devices-da8xx.c | 99 +++--------------------------
drivers/ata/Kconfig | 9 +++
drivers/ata/Makefile | 1 +
drivers/ata/ahci_da850.c | 116 ++++++++++++++++++++++++++++++++++
4 files changed, 134 insertions(+), 91 deletions(-)
create mode 100644 drivers/ata/ahci_da850.c

diff --git a/arch/arm/mach-davinci/devices-da8xx.c b/arch/arm/mach-davinci/devices-da8xx.c
index 0486cdf2..72bb8d6 100644
--- a/arch/arm/mach-davinci/devices-da8xx.c
+++ b/arch/arm/mach-davinci/devices-da8xx.c
@@ -1020,7 +1020,6 @@ int __init da8xx_register_spi_bus(int instance, unsigned num_chipselect)
}

#ifdef CONFIG_ARCH_DAVINCI_DA850
-
static struct resource da850_sata_resources[] = {
{
.start = DA850_SATA_BASE,
@@ -1028,103 +1027,22 @@ static struct resource da850_sata_resources[] = {
.flags = IORESOURCE_MEM,
},
{
+ .start = DA8XX_SYSCFG1_BASE,
+ .end = DA8XX_SYSCFG1_BASE + SZ_4K - 1,
+ .flags = IORESOURCE_MEM,
+ },
+ {
.start = IRQ_DA850_SATAINT,
.flags = IORESOURCE_IRQ,
},
};

-/* SATA PHY Control Register offset from AHCI base */
-#define SATA_P0PHYCR_REG 0x178
-
-#define SATA_PHY_MPY(x) ((x) << 0)
-#define SATA_PHY_LOS(x) ((x) << 6)
-#define SATA_PHY_RXCDR(x) ((x) << 10)
-#define SATA_PHY_RXEQ(x) ((x) << 13)
-#define SATA_PHY_TXSWING(x) ((x) << 19)
-#define SATA_PHY_ENPLL(x) ((x) << 31)
-
-static struct clk *da850_sata_clk;
-static unsigned long da850_sata_refclkpn;
-
-/* Supported DA850 SATA crystal frequencies */
-#define KHZ_TO_HZ(freq) ((freq) * 1000)
-static unsigned long da850_sata_xtal[] = {
- KHZ_TO_HZ(300000),
- KHZ_TO_HZ(250000),
- 0, /* Reserved */
- KHZ_TO_HZ(187500),
- KHZ_TO_HZ(150000),
- KHZ_TO_HZ(125000),
- KHZ_TO_HZ(120000),
- KHZ_TO_HZ(100000),
- KHZ_TO_HZ(75000),
- KHZ_TO_HZ(60000),
-};
-
-static int da850_sata_init(struct device *dev, void __iomem *addr)
-{
- int i, ret;
- unsigned int val;
-
- da850_sata_clk = clk_get(dev, NULL);
- if (IS_ERR(da850_sata_clk))
- return PTR_ERR(da850_sata_clk);
-
- ret = clk_prepare_enable(da850_sata_clk);
- if (ret)
- goto err0;
-
- /* Enable SATA clock receiver */
- val = __raw_readl(DA8XX_SYSCFG1_VIRT(DA8XX_PWRDN_REG));
- val &= ~BIT(0);
- __raw_writel(val, DA8XX_SYSCFG1_VIRT(DA8XX_PWRDN_REG));
-
- /* Get the multiplier needed for 1.5GHz PLL output */
- for (i = 0; i < ARRAY_SIZE(da850_sata_xtal); i++)
- if (da850_sata_xtal[i] == da850_sata_refclkpn)
- break;
-
- if (i == ARRAY_SIZE(da850_sata_xtal)) {
- ret = -EINVAL;
- goto err1;
- }
-
- val = SATA_PHY_MPY(i + 1) |
- SATA_PHY_LOS(1) |
- SATA_PHY_RXCDR(4) |
- SATA_PHY_RXEQ(1) |
- SATA_PHY_TXSWING(3) |
- SATA_PHY_ENPLL(1);
-
- __raw_writel(val, addr + SATA_P0PHYCR_REG);
-
- return 0;
-
-err1:
- clk_disable_unprepare(da850_sata_clk);
-err0:
- clk_put(da850_sata_clk);
- return ret;
-}
-
-static void da850_sata_exit(struct device *dev)
-{
- clk_disable_unprepare(da850_sata_clk);
- clk_put(da850_sata_clk);
-}
-
-static struct ahci_platform_data da850_sata_pdata = {
- .init = da850_sata_init,
- .exit = da850_sata_exit,
-};
-
static u64 da850_sata_dmamask = DMA_BIT_MASK(32);

static struct platform_device da850_sata_device = {
- .name = "ahci",
+ .name = "ahci_da850",
.id = -1,
.dev = {
- .platform_data = &da850_sata_pdata,
.dma_mask = &da850_sata_dmamask,
.coherent_dma_mask = DMA_BIT_MASK(32),
},
@@ -1134,9 +1052,8 @@ static struct platform_device da850_sata_device = {

int __init da850_register_sata(unsigned long refclkpn)
{
- da850_sata_refclkpn = refclkpn;
- if (!da850_sata_refclkpn)
- return -EINVAL;
+ /* please see comment in drivers/ata/ahci_da850.c */
+ BUG_ON(refclkpn != 100 * 1000 * 1000);

return platform_device_register(&da850_sata_device);
}
diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index 371e8890..4b71e73 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -97,6 +97,15 @@ config SATA_AHCI_PLATFORM

If unsure, say N.

+config AHCI_DA850
+ tristate "DaVinci DA850 AHCI SATA support"
+ depends on ARCH_DAVINCI_DA850
+ help
+ This option enables support for the DaVinci DA850 SoC's
+ onboard AHCI SATA.
+
+ If unsure, say N.
+
config AHCI_ST
tristate "ST AHCI SATA support"
depends on ARCH_STI
diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
index 6123e64..0646d83 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-$(CONFIG_AHCI_DA850) += ahci_da850.o libahci.o libahci_platform.o
obj-$(CONFIG_AHCI_IMX) += ahci_imx.o libahci.o libahci_platform.o
obj-$(CONFIG_AHCI_SUNXI) += ahci_sunxi.o libahci.o libahci_platform.o
obj-$(CONFIG_AHCI_ST) += ahci_st.o libahci.o libahci_platform.o
diff --git a/drivers/ata/ahci_da850.c b/drivers/ata/ahci_da850.c
new file mode 100644
index 0000000..899270a
--- /dev/null
+++ b/drivers/ata/ahci_da850.c
@@ -0,0 +1,116 @@
+/*
+ * DaVinci DA850 AHCI SATA platform driver
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pm.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/libata.h>
+#include <linux/ahci_platform.h>
+#include "ahci.h"
+
+#define DA8XX_PWRDN_REG 0x18
+
+/* SATA PHY Control Register offset from AHCI base */
+#define SATA_P0PHYCR_REG 0x178
+
+#define SATA_PHY_MPY(x) ((x) << 0)
+#define SATA_PHY_LOS(x) ((x) << 6)
+#define SATA_PHY_RXCDR(x) ((x) << 10)
+#define SATA_PHY_RXEQ(x) ((x) << 13)
+#define SATA_PHY_TXSWING(x) ((x) << 19)
+#define SATA_PHY_ENPLL(x) ((x) << 31)
+
+/*
+ * The multiplier needed for 1.5GHz PLL output.
+ *
+ * NOTE: This is currently hardcoded to be suitable for 100MHz crystal
+ * frequency (which is used by DA850 EVM board) and may need to be changed
+ * if you would like to use this driver on some other board.
+ */
+#define DA850_SATA_CLK_MULTIPLIER 7
+
+static void da850_sata_init(struct device *dev, void __iomem *syscfg1_base,
+ void __iomem *ahci_base)
+{
+ unsigned int val;
+
+ /* Enable SATA clock receiver */
+ val = readl(syscfg1_base + DA8XX_PWRDN_REG);
+ val &= ~BIT(0);
+ writel(val, syscfg1_base + DA8XX_PWRDN_REG);
+
+ val = SATA_PHY_MPY(DA850_SATA_CLK_MULTIPLIER + 1) | SATA_PHY_LOS(1) |
+ SATA_PHY_RXCDR(4) | SATA_PHY_RXEQ(1) | SATA_PHY_TXSWING(3) |
+ SATA_PHY_ENPLL(1);
+
+ writel(val, ahci_base + SATA_P0PHYCR_REG);
+}
+
+static const struct ata_port_info ahci_da850_port_info = {
+ .flags = AHCI_FLAG_COMMON,
+ .pio_mask = ATA_PIO4,
+ .udma_mask = ATA_UDMA6,
+ .port_ops = &ahci_platform_ops,
+};
+
+static int ahci_da850_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct ahci_host_priv *hpriv;
+ struct resource *res;
+ void __iomem *syscfg1_base;
+ int rc;
+
+ hpriv = ahci_platform_get_resources(pdev);
+ if (IS_ERR(hpriv))
+ return PTR_ERR(hpriv);
+
+ rc = ahci_platform_enable_resources(hpriv);
+ if (rc)
+ return rc;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (!res)
+ goto disable_resources;
+
+ syscfg1_base = devm_ioremap(dev, res->start, resource_size(res));
+ if (!syscfg1_base)
+ goto disable_resources;
+
+ da850_sata_init(dev, syscfg1_base, hpriv->mmio);
+
+ rc = ahci_platform_init_host(pdev, hpriv, &ahci_da850_port_info, 0, 0);
+ if (rc)
+ goto disable_resources;
+
+ return 0;
+disable_resources:
+ ahci_platform_disable_resources(hpriv);
+ return rc;
+}
+
+static SIMPLE_DEV_PM_OPS(ahci_da850_pm_ops, ahci_platform_suspend,
+ ahci_platform_resume);
+
+static struct platform_driver ahci_da850_driver = {
+ .probe = ahci_da850_probe,
+ .remove = ata_platform_remove_one,
+ .driver = {
+ .name = "ahci_da850",
+ .owner = THIS_MODULE,
+ .pm = &ahci_da850_pm_ops,
+ },
+};
+module_platform_driver(ahci_da850_driver);
+
+MODULE_DESCRIPTION("DaVinci DA850 AHCI SATA platform driver");
+MODULE_AUTHOR("Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>");
+MODULE_LICENSE("GPL");
--
1.8.2.3

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