[PATCH v2 2/4] ARM: sunxi: Add ahci-sunxi driver for the Allwinner SUNXi SoCs sata

[Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

From: Oliver Schinagl <oliver-dxLnbx3+1qmEVqv0pETR8A@public.gmane.org>

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

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 .

Given that almost all functionality already is shared through libahci /
ata-core, and that ahci_platform.c cannot cleanly handle somewhat more complex
platform specific ahci cases, such as the sunxi case, it was refactored into
a stand-alone platform driver by Hans de Goede.

Signed-off-by: Olliver Schinagl <oliver-dxLnbx3+1qmEVqv0pETR8A@public.gmane.org>
Signed-off-by: Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 .../devicetree/bindings/ata/ahci-sunxi.txt         |  24 ++
 drivers/ata/Kconfig                                |   9 +
 drivers/ata/Makefile                               |   1 +
 drivers/ata/ahci_sunxi.c                           | 349 +++++++++++++++++++++
 4 files changed, 383 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/ata/ahci-sunxi.txt
 create mode 100644 drivers/ata/ahci_sunxi.c

diff --git a/Documentation/devicetree/bindings/ata/ahci-sunxi.txt b/Documentation/devicetree/bindings/ata/ahci-sunxi.txt
new file mode 100644
index 0000000..0792fa5
--- /dev/null
+++ b/Documentation/devicetree/bindings/ata/ahci-sunxi.txt
@@ -0,0 +1,24 @@
+Allwinner SUNXI AHCI SATA Controller
+
+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 "allwinner,sun4i-a10-ahci"
+- reg		: <registers mapping>
+- interrupts	: <interrupt mapping for AHCI IRQ>
+- clocks	: clocks for ACHI
+- clock-names	: clock names for AHCI
+
+Optional properties:
+- pwr-supply	: regulator to control the power supply GPIO
+
+Example:
+	ahci@01c18000 {
+		compatible = "allwinner,sun4i-a10-ahci";
+		reg = <0x01c18000 0x1000>;
+		interrupts = <0 56 1>;
+		clocks = <&ahb_gates 25>, <&pll6 0>;
+		clock-names = "ahb_sata", "pll6_sata";
+		pwr-supply = <&reg_ahci_5v>;
+	};
diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index 4e73772..3c80bbe 100644
--- a/drivers/ata/Kconfig
+++ b/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
+	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
diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
index 46518c6..956abc3 100644
--- a/drivers/ata/Makefile
+++ b/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 libahci.o
 
 # SFF w/ custom DMA
 obj-$(CONFIG_PDC_ADMA)		+= pdc_adma.o
diff --git a/drivers/ata/ahci_sunxi.c b/drivers/ata/ahci_sunxi.c
new file mode 100644
index 0000000..22d3972
--- /dev/null
+++ b/drivers/ata/ahci_sunxi.c
@@ -0,0 +1,349 @@
+/*
+ * Allwinner sunxi AHCI SATA platform driver
+ * Copyright 2013 Olliver Schinagl <oliver-dxLnbx3+1qmEVqv0pETR8A@public.gmane.org>
+ * Copyright 2014 Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
+ *
+ * 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-0TFLnhJekD6UEPyfVivIlAC/G2K4zDHf@public.gmane.org>
+ *
+ * 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/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
+
+struct sunxi_ahci {
+	struct ahci_host_priv hpriv;
+	struct regulator *pwr;
+	struct clk *sata_clk;
+	struct clk *ahb_clk;
+};
+
+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 sunxi_ahci_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 = 0x100000;
+	do {
+		reg_val = sunxi_getbits(reg_base + AHCI_PHYCS0R, 0x7, 28);
+	} while (--timeout && (reg_val != 0x2));
+	if (!timeout) {
+		dev_err(dev, "PHY power up failed.\n");
+		return -EIO;
+	}
+
+	sunxi_setbits(reg_base + AHCI_PHYCS2R, (0x1 << 24));
+
+	timeout = 0x100000;
+	do {
+		reg_val = sunxi_getbits(reg_base + AHCI_PHYCS2R, 0x1, 24);
+	} while (--timeout && reg_val);
+	if (!timeout) {
+		dev_err(dev, "PHY calibration failed.\n");
+		return -EIO;
+	}
+	mdelay(15);
+
+	writel(0x7, reg_base + AHCI_RWCR);
+
+	return 0;
+}
+
+void sunxi_ahci_pre_start_engine(struct ata_port *ap)
+{
+	struct ahci_host_priv *hpriv = ap->host->private_data;
+
+	/* Setup DMA before DMA start */
+	sunxi_clrsetbits(hpriv->mmio + AHCI_P0DMACR, 0x0000ff00, 0x00004400);
+}
+
+static int sunxi_ahci_enable_clks(struct sunxi_ahci *ahci)
+{
+	int ret;
+
+	ret = clk_prepare_enable(ahci->sata_clk);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(ahci->ahb_clk);
+	if (ret)
+		clk_disable_unprepare(ahci->sata_clk);
+
+	return ret;
+}
+
+static void sunxi_ahci_disable_clks(struct sunxi_ahci *ahci)
+{
+	clk_disable_unprepare(ahci->ahb_clk);
+	clk_disable_unprepare(ahci->sata_clk);
+}
+
+static void sunxi_ahci_host_stop(struct ata_host *host)
+{
+	struct ahci_host_priv *hpriv = host->private_data;
+	struct sunxi_ahci *ahci = hpriv->plat_data;
+
+	if (!IS_ERR(ahci->pwr))
+		regulator_disable(ahci->pwr);
+
+	sunxi_ahci_disable_clks(ahci);
+}
+
+static struct ata_port_operations sunxi_ahci_platform_ops = {
+	.inherits	= &ahci_ops,
+	.host_stop	= sunxi_ahci_host_stop,
+};
+
+static const struct ata_port_info sunxiahci_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	= &sunxi_ahci_platform_ops,
+};
+
+static struct scsi_host_template sunxi_ahci_platform_sht = {
+	AHCI_SHT("sunxi_ahci"),
+};
+
+static int sunxi_ahci_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	const struct ata_port_info *ppi[] = { &sunxiahci_port_info, NULL };
+	struct sunxi_ahci *ahci;
+	struct ata_host *host;
+	int ret;
+
+	ahci = devm_kzalloc(&pdev->dev, sizeof(*ahci), GFP_KERNEL);
+	if (!ahci)
+		return -ENOMEM;
+
+	ahci->pwr = devm_regulator_get_optional(dev, "pwr");
+	if (IS_ERR(ahci->pwr) && PTR_ERR(ahci->pwr) == -EPROBE_DEFER)
+		return -EPROBE_DEFER;
+
+	host = ata_host_alloc_pinfo(dev, ppi, 1);
+	if (!host)
+		return -ENOMEM;
+
+	host->private_data = &ahci->hpriv;
+	host->flags |= ATA_HOST_PARALLEL_SCAN;
+
+	ahci->hpriv.flags = (unsigned long)ppi[0]->private_data;
+	ahci->hpriv.plat_data = ahci;
+	ahci->hpriv.pre_start_engine = sunxi_ahci_pre_start_engine;
+	ahci->hpriv.mmio = devm_ioremap_resource(dev,
+			      platform_get_resource(pdev, IORESOURCE_MEM, 0));
+	if (IS_ERR(ahci->hpriv.mmio))
+		return PTR_ERR(ahci->hpriv.mmio);
+
+	ahci->ahb_clk = devm_clk_get(&pdev->dev, "ahb_sata");
+	if (IS_ERR(ahci->ahb_clk))
+		return PTR_ERR(ahci->ahb_clk);
+
+	ahci->sata_clk = devm_clk_get(&pdev->dev, "pll6_sata");
+	if (IS_ERR(ahci->sata_clk))
+		return PTR_ERR(ahci->sata_clk);
+
+	ret = sunxi_ahci_enable_clks(ahci);
+	if (ret)
+		return ret;
+
+	if (!IS_ERR(ahci->pwr)) {
+		ret = regulator_enable(ahci->pwr);
+		if (ret) {
+			sunxi_ahci_disable_clks(ahci);
+			return ret;
+		}
+	}
+
+	ret = sunxi_ahci_phy_init(dev, ahci->hpriv.mmio);
+	if (ret) {
+		sunxi_ahci_host_stop(host);
+		return ret;
+	}
+
+	ahci_save_initial_config(dev, &ahci->hpriv, 0, 0);
+
+	ret = ahci_reset_controller(host);
+	if (ret) {
+		sunxi_ahci_host_stop(host);
+		return ret;
+	}
+
+	ahci_init_controller(host);
+	ahci_print_info(host, "sunxi");
+
+	ret = ata_host_activate(host, platform_get_irq(pdev, 0),
+				ahci_interrupt, 0, &sunxi_ahci_platform_sht);
+	if (ret)
+		sunxi_ahci_host_stop(host);
+
+	return ret;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int sunxi_ahci_susp(struct device *dev)
+{
+	struct ata_host *host = dev_get_drvdata(dev);
+	struct ahci_host_priv *hpriv = host->private_data;
+	struct sunxi_ahci *ahci = hpriv->plat_data;
+	int ret;
+
+	/*
+	 * AHCI spec rev1.1 section 8.3.3:
+	 * Software must disable interrupts prior to requesting a
+	 * transition of the HBA to D3 state.
+	 */
+	sunxi_clrbits(hpriv->mmio + HOST_CTL, HOST_IRQ_EN);
+
+	ret = ata_host_suspend(host, PMSG_SUSPEND);
+	if (ret)
+		return ret;
+
+	sunxi_ahci_disable_clks(ahci);
+
+	return 0;
+}
+
+static int sunxi_ahci_resume(struct device *dev)
+{
+	struct ata_host *host = dev_get_drvdata(dev);
+	struct ahci_host_priv *hpriv = host->private_data;
+	struct sunxi_ahci *ahci = hpriv->plat_data;
+	int ret;
+
+	ret = sunxi_ahci_enable_clks(ahci);
+	if (ret)
+		return ret;
+
+	if (dev->power.power_state.event == PM_EVENT_SUSPEND) {
+		ret = ahci_reset_controller(host);
+		if (ret)
+			return ret;
+
+		ahci_init_controller(host);
+	}
+
+	ata_host_resume(host);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(sunxi_ahci_pmo, sunxi_ahci_susp, sunxi_ahci_resume);
+
+static const struct of_device_id sunxi_ahci_of_match[] = {
+	{ .compatible = "allwinner,sun4i-a10-ahci" },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, sunxi_ahci_of_match);
+
+static struct platform_driver sunxi_ahci_driver = {
+	.probe = sunxi_ahci_probe,
+	.remove = ata_platform_remove_one,
+	.driver = {
+		.name = "sunxi-ahci",
+		.owner = THIS_MODULE,
+		.of_match_table = sunxi_ahci_of_match,
+		.pm = &sunxi_ahci_pmo,
+	},
+};
+module_platform_driver(sunxi_ahci_driver);
+
+MODULE_DESCRIPTION("Allwinner sunxi AHCI SATA platform driver");
+MODULE_AUTHOR("Olliver Schinagl <oliver-dxLnbx3+1qmEVqv0pETR8A@public.gmane.org>");
+MODULE_LICENSE("GPL");
-- 
1.8.4.2