[v9 3/3] ahci_imx: add ahci sata support on imx platforms

[Richard Zhu <richard.zhuhongxing@gmail.com>]

From: Richard Zhu <r65037@freescale.com>

imx6q contains one Synopsys AHCI SATA controller,
But it can't share ahci_platform driver with other
controllers.
Because there are some misalignments of the generic
AHCI controller.
The bits definitions of the HBA registers, the Vendor
Specific registers, the AHCI PHY clock and the AHCI
signals adjustment window(GPR13 register).
 - CAP_SSS(bit20) of the HOST_CAP is writable, default
 value is '0', should be configured to be '1'
 - bit0 (only one AHCI SATA port on imx6q) of the
 HOST_PORTS_IMPL should be set to be '1'.(default 0)
 - One Vendor Specific register HOST_TIMER1MS(offset:0xe0)
 should be configured regarding to the frequency of AHB
 bus clock.
 - Configurations of the AHCI PHY clock, and the signal
 parameters of the GPR13

Setup its own ahci sata driver, contained the imx6q specific
initialized codes, re-use the generic ahci_platform driver, and
keep the generic ahci_platform driver clean as much as possible.

Signed-off-by: Richard Zhu <r65037@freescale.com>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
---
 drivers/ata/Kconfig    |    9 ++
 drivers/ata/Makefile   |    1 +
 drivers/ata/ahci_imx.c |  236 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 246 insertions(+), 0 deletions(-)
 create mode 100644 drivers/ata/ahci_imx.c

diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index a5a3ebc..bc0739d 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -97,6 +97,15 @@ config SATA_AHCI_PLATFORM
 
 	  If unsure, say N.
 
+config AHCI_IMX
+	tristate "Freescale i.MX AHCI SATA support"
+	depends on SATA_AHCI_PLATFORM && MFD_SYSCON
+	help
+	  This option enables support for the Freescale i.MX 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 c04d0fd..46518c6 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_IMX)		+= ahci_imx.o
 
 # SFF w/ custom DMA
 obj-$(CONFIG_PDC_ADMA)		+= pdc_adma.o
diff --git a/drivers/ata/ahci_imx.c b/drivers/ata/ahci_imx.c
new file mode 100644
index 0000000..58debb0
--- /dev/null
+++ b/drivers/ata/ahci_imx.c
@@ -0,0 +1,236 @@
+/*
+ * Freescale IMX AHCI SATA platform driver
+ * Copyright 2013 Freescale Semiconductor, Inc.
+ *
+ * based on the AHCI SATA platform driver by Jeff Garzik and Anton Vorontsov
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/ahci_platform.h>
+#include <linux/of_device.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
+#include "ahci.h"
+
+enum {
+	HOST_TIMER1MS = 0xe0, /* Timer 1-ms */
+};
+
+struct imx_ahci_priv {
+	struct platform_device *ahci_pdev;
+	struct clk *sata_ref_clk;
+	struct clk *ahb_clk;
+	struct regmap *gpr;
+};
+
+static int imx6q_sata_init(struct device *dev, void __iomem *mmio)
+{
+	int ret = 0;
+	unsigned int reg_val;
+	struct imx_ahci_priv *imxpriv = dev_get_drvdata(dev->parent);
+
+	imxpriv->gpr =
+		syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
+	if (IS_ERR(imxpriv->gpr)) {
+		dev_err(dev, "failed to find fsl,imx6q-iomux-gpr regmap\n");
+		return PTR_ERR(imxpriv->gpr);
+	}
+
+	ret = clk_prepare_enable(imxpriv->sata_ref_clk);
+	if (ret < 0) {
+		dev_err(dev, "prepare-enable sata_ref clock err:%d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * set PHY Paremeters, two steps to configure the GPR13,
+	 * one write for rest of parameters, mask of first write
+	 * is 0x07fffffd, and the other one write for setting
+	 * the mpll_clk_en.
+	 */
+	regmap_update_bits(imxpriv->gpr, 0x34, IMX6Q_GPR13_SATA_RX_EQ_VAL_MASK
+			| IMX6Q_GPR13_SATA_RX_LOS_LVL_MASK
+			| IMX6Q_GPR13_SATA_RX_DPLL_MODE_MASK
+			| IMX6Q_GPR13_SATA_SPD_MODE_MASK
+			| IMX6Q_GPR13_SATA_MPLL_SS_EN
+			| IMX6Q_GPR13_SATA_TX_ATTEN_MASK
+			| IMX6Q_GPR13_SATA_TX_BOOST_MASK
+			| IMX6Q_GPR13_SATA_TX_LVL_MASK
+			| IMX6Q_GPR13_SATA_TX_EDGE_RATE
+			, IMX6Q_GPR13_SATA_RX_EQ_VAL_3_0_DB
+			| IMX6Q_GPR13_SATA_RX_LOS_LVL_SATA2M
+			| IMX6Q_GPR13_SATA_RX_DPLL_MODE_2P_4F
+			| IMX6Q_GPR13_SATA_SPD_MODE_3P0G
+			| IMX6Q_GPR13_SATA_MPLL_SS_EN
+			| IMX6Q_GPR13_SATA_TX_ATTEN_9_16
+			| IMX6Q_GPR13_SATA_TX_BOOST_3_33_DB
+			| IMX6Q_GPR13_SATA_TX_LVL_1_025_V);
+	regmap_update_bits(imxpriv->gpr, 0x34, IMX6Q_GPR13_SATA_MPLL_CLK_EN,
+			IMX6Q_GPR13_SATA_MPLL_CLK_EN);
+	usleep_range(100, 200);
+
+	/*
+	 * Configure the HWINIT bits of the HOST_CAP and HOST_PORTS_IMPL,
+	 * and IP vendor specific register HOST_TIMER1MS.
+	 * Configure CAP_SSS (support stagered spin up).
+	 * Implement the port0.
+	 * Get the ahb clock rate, and configure the TIMER1MS register.
+	 */
+	reg_val = readl(mmio + HOST_CAP);
+	if (!(reg_val & HOST_CAP_SSS)) {
+		reg_val |= HOST_CAP_SSS;
+		writel(reg_val, mmio + HOST_CAP);
+	}
+	reg_val = readl(mmio + HOST_PORTS_IMPL);
+	if (!(reg_val & 0x1)) {
+		reg_val |= 0x1;
+		writel(reg_val, mmio + HOST_PORTS_IMPL);
+	}
+
+	reg_val = clk_get_rate(imxpriv->ahb_clk) / 1000;
+	writel(reg_val, mmio + HOST_TIMER1MS);
+
+	return 0;
+}
+
+static void imx6q_sata_exit(struct device *dev)
+{
+	struct imx_ahci_priv *imxpriv =  dev_get_drvdata(dev->parent);
+
+	regmap_update_bits(imxpriv->gpr, 0x34, IMX6Q_GPR13_SATA_MPLL_CLK_EN,
+			!IMX6Q_GPR13_SATA_MPLL_CLK_EN);
+	clk_disable_unprepare(imxpriv->sata_ref_clk);
+}
+
+static struct ahci_platform_data imx6q_sata_pdata = {
+	.init = imx6q_sata_init,
+	.exit = imx6q_sata_exit,
+};
+
+static const struct of_device_id imx_ahci_of_match[] = {
+	{ .compatible = "fsl,imx6q-ahci", .data = &imx6q_sata_pdata},
+	{},
+};
+MODULE_DEVICE_TABLE(of, imx_ahci_of_match);
+
+static int imx_ahci_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct resource *mem, *irq, res[2];
+	const struct of_device_id *of_id;
+	const struct ahci_platform_data *pdata = NULL;
+	struct imx_ahci_priv *imxpriv;
+	struct device *ahci_dev;
+	struct platform_device *ahci_pdev;
+	int ret;
+
+	imxpriv = devm_kzalloc(dev, sizeof(*imxpriv), GFP_KERNEL);
+	if (!imxpriv) {
+		dev_err(dev, "can't alloc ahci_host_priv\n");
+		return -ENOMEM;
+	}
+
+	ahci_pdev = platform_device_alloc("ahci", -1);
+	if (!ahci_pdev)
+		return -ENODEV;
+
+	ahci_dev = &ahci_pdev->dev;
+	ahci_dev->parent = dev;
+
+	imxpriv->ahb_clk = devm_clk_get(dev, "ahb");
+	if (IS_ERR(imxpriv->ahb_clk)) {
+		dev_err(dev, "can't get ahb clock.\n");
+		ret = PTR_ERR(imxpriv->ahb_clk);
+		goto err_out;
+	}
+
+	imxpriv->sata_ref_clk = devm_clk_get(dev, "sata_ref");
+	if (IS_ERR(imxpriv->sata_ref_clk)) {
+		dev_err(dev, "can't get sata_ref clock.\n");
+		ret = PTR_ERR(imxpriv->sata_ref_clk);
+		goto err_out;
+	}
+
+	imxpriv->ahci_pdev = ahci_pdev;
+	platform_set_drvdata(pdev, imxpriv);
+
+	of_id = of_match_device(imx_ahci_of_match, dev);
+	if (of_id) {
+		pdata = of_id->data;
+	} else {
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!mem || !irq) {
+		dev_err(dev, "no mmio/irq resource\n");
+		ret = -ENOMEM;
+		goto err_out;
+	}
+
+	res[0] = *mem;
+	res[1] = *irq;
+
+	ahci_dev->coherent_dma_mask = DMA_BIT_MASK(32);
+	ahci_dev->dma_mask = &ahci_dev->coherent_dma_mask;
+	ahci_dev->of_node = dev->of_node;
+
+	ret = platform_device_add_resources(ahci_pdev, res, 2);
+	if (ret)
+		goto err_out;
+
+	ret = platform_device_add_data(ahci_pdev, pdata, sizeof(*pdata));
+	if (ret)
+		goto err_out;
+
+	ret = platform_device_add(ahci_pdev);
+	if (ret) {
+err_out:
+		platform_device_put(ahci_pdev);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int imx_ahci_remove(struct platform_device *pdev)
+{
+	struct imx_ahci_priv *imxpriv = platform_get_drvdata(pdev);
+	struct platform_device *ahci_pdev = imxpriv->ahci_pdev;
+
+	platform_device_unregister(ahci_pdev);
+	return 0;
+}
+
+static struct platform_driver imx_ahci_driver = {
+	.probe = imx_ahci_probe,
+	.remove = imx_ahci_remove,
+	.driver = {
+		.name = "ahci-imx",
+		.owner = THIS_MODULE,
+		.of_match_table = imx_ahci_of_match,
+	},
+};
+module_platform_driver(imx_ahci_driver);
+
+MODULE_DESCRIPTION("Freescale i.MX AHCI SATA platform driver");
+MODULE_AUTHOR("Richard Zhu <Hong-Xing.Zhu@freescale.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("ahci:imx");
-- 
1.7.5.4