ARM: sunxi: Add support for Allwinner SUNXi SoCs sata to ahci_platform

This patch adds support for the ahci sata controler found on Allwinner A10
and A20 SoCs to the ahci_platform driver.

Orignally written by Olliver Schinagl using the approach of having a platform
device which probe method creates a new child platform device which gets
driven by ahci_platform.c, as done by ahci_imx.c .

Refactored by Hans de Goede to add most of the non sunxi specific functionality
to ahci_platform.c and use a platform_data pointer from of_device_id for the
sunxi specific bits.
Signed-off-by: Olliver Schinagl <oliver@schinagl.nl>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Documentation/devicetree/bindings/ata/ahci-platform.txt

@@ -4,7 +4,9 @@ SATA nodes are defined to describe on-chip Serial ATA controllers.
 Each SATA controller should have its own node.
 
 Required properties:
-- compatible        : compatible list, contains "snps,spear-ahci"
+- compatible        : compatible list, one of "snps,spear-ahci",
+                      "snps,exynos5440-ahci", "ibm,476gtr-ahci", or
+                      "allwinner,sun4i-a10-ahci"
 - interrupts        : <interrupt mapping for SATA IRQ>
 - reg               : <registers mapping>
 
@@ -13,10 +15,17 @@ Optional properties:
 - clocks            : a list of phandle + clock specifier pairs
 - target-supply     : regulator for SATA target power
 
-Example:
+Examples:
         sata@ffe08000 {
 		compatible = "snps,spear-ahci";
 		reg = <0xffe08000 0x1000>;
 		interrupts = <115>;
-
         };
+
+	ahci: sata@01c18000 {
+		compatible = "allwinner,sun4i-a10-ahci";
+		reg = <0x01c18000 0x1000>;
+		interrupts = <56>;
+		clocks = <&pll6 0>, <&ahb_gates 25>;
+		target-supply = <&reg_ahci_5v>;
+	};

drivers/ata/Kconfig

@@ -106,6 +106,15 @@ config AHCI_IMX
 
 	  If unsure, say N.
 
+config AHCI_SUNXI
+	tristate "Allwinner sunxi AHCI SATA support"
+	depends on ARCH_SUNXI && SATA_AHCI_PLATFORM
+	help
+	  This option enables support for the Allwinner sunxi SoC's
+	  onboard AHCI SATA.
+
+	  If unsure, say N.
+
 config SATA_FSL
 	tristate "Freescale 3.0Gbps SATA support"
 	depends on FSL_SOC

drivers/ata/Makefile

@@ -11,6 +11,7 @@ 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_IMX)		+= ahci_imx.o
+obj-$(CONFIG_AHCI_SUNXI)	+= ahci_sunxi.o
 
 # SFF w/ custom DMA
 obj-$(CONFIG_PDC_ADMA)		+= pdc_adma.o

drivers/ata/ahci_sunxi.c

+/*
+ * Allwinner sunxi AHCI SATA platform driver
+ * Copyright 2013 Olliver Schinagl <oliver@schinagl.nl>
+ * Copyright 2014 Hans de Goede <hdegoede@redhat.com>
+ *
+ * based on the AHCI SATA platform driver by Jeff Garzik and Anton Vorontsov
+ * Based on code from Allwinner Technology Co., Ltd. <www.allwinnertech.com>,
+ * Daniel Wang <danielwang@allwinnertech.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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/clk.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/regulator/consumer.h>
+#include "ahci.h"
+
+#define AHCI_BISTAFR 0x00a0
+#define AHCI_BISTCR 0x00a4
+#define AHCI_BISTFCTR 0x00a8
+#define AHCI_BISTSR 0x00ac
+#define AHCI_BISTDECR 0x00b0
+#define AHCI_DIAGNR0 0x00b4
+#define AHCI_DIAGNR1 0x00b8
+#define AHCI_OOBR 0x00bc
+#define AHCI_PHYCS0R 0x00c0
+#define AHCI_PHYCS1R 0x00c4
+#define AHCI_PHYCS2R 0x00c8
+#define AHCI_TIMER1MS 0x00e0
+#define AHCI_GPARAM1R 0x00e8
+#define AHCI_GPARAM2R 0x00ec
+#define AHCI_PPARAMR 0x00f0
+#define AHCI_TESTR 0x00f4
+#define AHCI_VERSIONR 0x00f8
+#define AHCI_IDR 0x00fc
+#define AHCI_RWCR 0x00fc
+#define AHCI_P0DMACR 0x0170
+#define AHCI_P0PHYCR 0x0178
+#define AHCI_P0PHYSR 0x017c
+
+static void sunxi_clrbits(void __iomem *reg, u32 clr_val)
+{
+	u32 reg_val;
+
+	reg_val = readl(reg);
+	reg_val &= ~(clr_val);
+	writel(reg_val, reg);
+}
+
+static void sunxi_setbits(void __iomem *reg, u32 set_val)
+{
+	u32 reg_val;
+
+	reg_val = readl(reg);
+	reg_val |= set_val;
+	writel(reg_val, reg);
+}
+
+static void sunxi_clrsetbits(void __iomem *reg, u32 clr_val, u32 set_val)
+{
+	u32 reg_val;
+
+	reg_val = readl(reg);
+	reg_val &= ~(clr_val);
+	reg_val |= set_val;
+	writel(reg_val, reg);
+}
+
+static u32 sunxi_getbits(void __iomem *reg, u8 mask, u8 shift)
+{
+	return (readl(reg) >> shift) & mask;
+}
+
+static int ahci_sunxi_phy_init(struct device *dev, void __iomem *reg_base)
+{
+	u32 reg_val;
+	int timeout;
+
+	/* This magic is from the original code */
+	writel(0, reg_base + AHCI_RWCR);
+	mdelay(5);
+
+	sunxi_setbits(reg_base + AHCI_PHYCS1R, BIT(19));
+	sunxi_clrsetbits(reg_base + AHCI_PHYCS0R,
+			 (0x7 << 24),
+			 (0x5 << 24) | BIT(23) | BIT(18));
+	sunxi_clrsetbits(reg_base + AHCI_PHYCS1R,
+			 (0x3 << 16) | (0x1f << 8) | (0x3 << 6),
+			 (0x2 << 16) | (0x6 << 8) | (0x2 << 6));
+	sunxi_setbits(reg_base + AHCI_PHYCS1R, BIT(28) | BIT(15));
+	sunxi_clrbits(reg_base + AHCI_PHYCS1R, BIT(19));
+	sunxi_clrsetbits(reg_base + AHCI_PHYCS0R,
+			 (0x7 << 20), (0x3 << 20));
+	sunxi_clrsetbits(reg_base + AHCI_PHYCS2R,
+			 (0x1f << 5), (0x19 << 5));
+	mdelay(5);
+
+	sunxi_setbits(reg_base + AHCI_PHYCS0R, (0x1 << 19));
+
+	timeout = 250; /* Power up takes aprox 50 us */
+	do {
+		reg_val = sunxi_getbits(reg_base + AHCI_PHYCS0R, 0x7, 28);
+		if (reg_val == 0x02)
+			break;
+
+		if (--timeout == 0) {
+			dev_err(dev, "PHY power up failed.\n");
+			return -EIO;
+		}
+		udelay(1);
+	} while (1);
+
+	sunxi_setbits(reg_base + AHCI_PHYCS2R, (0x1 << 24));
+
+	timeout = 100; /* Calibration takes aprox 10 us */
+	do {
+		reg_val = sunxi_getbits(reg_base + AHCI_PHYCS2R, 0x1, 24);
+		if (reg_val == 0x00)
+			break;
+
+		if (--timeout == 0) {
+			dev_err(dev, "PHY calibration failed.\n");
+			return -EIO;
+		}
+		udelay(1);
+	} while (1);
+
+	mdelay(15);
+
+	writel(0x7, reg_base + AHCI_RWCR);
+
+	return 0;
+}
+
+static void ahci_sunxi_start_engine(struct ata_port *ap)
+{
+	void __iomem *port_mmio = ahci_port_base(ap);
+	struct ahci_host_priv *hpriv = ap->host->private_data;
+
+	/* Setup DMA before DMA start */
+	sunxi_clrsetbits(hpriv->mmio + AHCI_P0DMACR, 0x0000ff00, 0x00004400);
+
+	/* Start DMA */
+	sunxi_setbits(port_mmio + PORT_CMD, PORT_CMD_START);
+}
+
+static const struct ata_port_info ahci_sunxi_port_info = {
+	AHCI_HFLAGS(AHCI_HFLAG_32BIT_ONLY | AHCI_HFLAG_NO_MSI |
+			  AHCI_HFLAG_NO_PMP | AHCI_HFLAG_YES_NCQ),
+	.flags		= AHCI_FLAG_COMMON | ATA_FLAG_NCQ,
+	.pio_mask	= ATA_PIO4,
+	.udma_mask	= ATA_UDMA6,
+	.port_ops	= &ahci_platform_ops,
+};
+
+static int ahci_sunxi_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ahci_host_priv *hpriv;
+	int rc;
+
+	hpriv = ahci_platform_get_resources(pdev);
+	if (IS_ERR(hpriv))
+		return PTR_ERR(hpriv);
+
+	hpriv->start_engine = ahci_sunxi_start_engine;
+
+	rc = ahci_platform_enable_resources(hpriv);
+	if (rc)
+		return rc;
+
+	rc = ahci_sunxi_phy_init(dev, hpriv->mmio);
+	if (rc)
+		goto disable_resources;
+
+	rc = ahci_platform_init_host(pdev, hpriv, &ahci_sunxi_port_info, 0, 0);
+	if (rc)
+		goto disable_resources;
+
+	return 0;
+
+disable_resources:
+	ahci_platform_disable_resources(hpriv);
+	return rc;
+}
+
+#ifdef CONFIG_PM_SLEEP
+int ahci_sunxi_resume(struct device *dev)
+{
+	struct ata_host *host = dev_get_drvdata(dev);
+	struct ahci_host_priv *hpriv = host->private_data;
+	int rc;
+
+	rc = ahci_platform_enable_resources(hpriv);
+	if (rc)
+		return rc;
+
+	rc = ahci_sunxi_phy_init(dev, hpriv->mmio);
+	if (rc)
+		goto disable_resources;
+
+	rc = ahci_platform_resume_host(dev);
+	if (rc)
+		goto disable_resources;
+
+	return 0;
+
+disable_resources:
+	ahci_platform_disable_resources(hpriv);
+	return rc;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(ahci_sunxi_pm_ops, ahci_platform_suspend,
+			 ahci_sunxi_resume);
+
+static const struct of_device_id ahci_sunxi_of_match[] = {
+	{ .compatible = "allwinner,sun4i-a10-ahci", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, ahci_sunxi_of_match);
+
+static struct platform_driver ahci_sunxi_driver = {
+	.probe = ahci_sunxi_probe,
+	.remove = ata_platform_remove_one,
+	.driver = {
+		.name = "ahci-sunxi",
+		.owner = THIS_MODULE,
+		.of_match_table = ahci_sunxi_of_match,
+		.pm = &ahci_sunxi_pm_ops,
+	},
+};
+module_platform_driver(ahci_sunxi_driver);
+
+MODULE_DESCRIPTION("Allwinner sunxi AHCI SATA driver");
+MODULE_AUTHOR("Olliver Schinagl <oliver@schinagl.nl>");
+MODULE_LICENSE("GPL");