phy: Add drivers for PCIe and SATA phy on SPEAr13xx

ARM based ST Microelectronics's SPEAr1310/40 platforms uses ST's phy (known as
'miphy') for PCIe and SATA. This patch adds drivers for these miphys.

This also adds proper bindings for miphys.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Pratyush Anand <pratyush.anand@st.com>
Tested-by: Mohit Kumar <mohit.kumar@st.com>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
[viresh: fixed logs/cclist/checkpatch warnings, broken into smaller patches]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

1 files changed, 307 insertions, 0 deletions

diff --git a/drivers/phy/phy-spear1340-miphy.c b/drivers/phy/phy-spear1340-miphy.c
new file mode 100644
index 000000000000..8de98adf21c3
--- /dev/null
+++ b/drivers/phy/phy-spear1340-miphy.c
@@ -0,0 +1,307 @@
+/*
+ * ST spear1340-miphy driver
+ *
+ * Copyright (C) 2014 ST Microelectronics
+ * Pratyush Anand <pratyush.anand@st.com>
+ * Mohit Kumar <mohit.kumar@st.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/phy/phy.h>
+#include <linux/regmap.h>
+
+/* SPEAr1340 Registers */
+/* Power Management Registers */
+#define SPEAR1340_PCM_CFG			0x100
+	#define SPEAR1340_PCM_CFG_SATA_POWER_EN		BIT(11)
+#define SPEAR1340_PCM_WKUP_CFG			0x104
+#define SPEAR1340_SWITCH_CTR			0x108
+
+#define SPEAR1340_PERIP1_SW_RST			0x318
+	#define SPEAR1340_PERIP1_SW_RSATA		BIT(12)
+#define SPEAR1340_PERIP2_SW_RST			0x31C
+#define SPEAR1340_PERIP3_SW_RST			0x320
+
+/* PCIE - SATA configuration registers */
+#define SPEAR1340_PCIE_SATA_CFG			0x424
+	/* PCIE CFG MASks */
+	#define SPEAR1340_PCIE_CFG_DEVICE_PRESENT	BIT(11)
+	#define SPEAR1340_PCIE_CFG_POWERUP_RESET	BIT(10)
+	#define SPEAR1340_PCIE_CFG_CORE_CLK_EN		BIT(9)
+	#define SPEAR1340_PCIE_CFG_AUX_CLK_EN		BIT(8)
+	#define SPEAR1340_SATA_CFG_TX_CLK_EN		BIT(4)
+	#define SPEAR1340_SATA_CFG_RX_CLK_EN		BIT(3)
+	#define SPEAR1340_SATA_CFG_POWERUP_RESET	BIT(2)
+	#define SPEAR1340_SATA_CFG_PM_CLK_EN		BIT(1)
+	#define SPEAR1340_PCIE_SATA_SEL_PCIE		(0)
+	#define SPEAR1340_PCIE_SATA_SEL_SATA		(1)
+	#define SPEAR1340_PCIE_SATA_CFG_MASK		0xF1F
+	#define SPEAR1340_PCIE_CFG_VAL	(SPEAR1340_PCIE_SATA_SEL_PCIE | \
+			SPEAR1340_PCIE_CFG_AUX_CLK_EN | \
+			SPEAR1340_PCIE_CFG_CORE_CLK_EN | \
+			SPEAR1340_PCIE_CFG_POWERUP_RESET | \
+			SPEAR1340_PCIE_CFG_DEVICE_PRESENT)
+	#define SPEAR1340_SATA_CFG_VAL	(SPEAR1340_PCIE_SATA_SEL_SATA | \
+			SPEAR1340_SATA_CFG_PM_CLK_EN | \
+			SPEAR1340_SATA_CFG_POWERUP_RESET | \
+			SPEAR1340_SATA_CFG_RX_CLK_EN | \
+			SPEAR1340_SATA_CFG_TX_CLK_EN)
+
+#define SPEAR1340_PCIE_MIPHY_CFG		0x428
+	#define SPEAR1340_MIPHY_OSC_BYPASS_EXT		BIT(31)
+	#define SPEAR1340_MIPHY_CLK_REF_DIV2		BIT(27)
+	#define SPEAR1340_MIPHY_CLK_REF_DIV4		(2 << 27)
+	#define SPEAR1340_MIPHY_CLK_REF_DIV8		(3 << 27)
+	#define SPEAR1340_MIPHY_PLL_RATIO_TOP(x)	(x << 0)
+	#define SPEAR1340_PCIE_MIPHY_CFG_MASK		0xF80000FF
+	#define SPEAR1340_PCIE_SATA_MIPHY_CFG_SATA \
+			(SPEAR1340_MIPHY_OSC_BYPASS_EXT | \
+			SPEAR1340_MIPHY_CLK_REF_DIV2 | \
+			SPEAR1340_MIPHY_PLL_RATIO_TOP(60))
+	#define SPEAR1340_PCIE_SATA_MIPHY_CFG_SATA_25M_CRYSTAL_CLK \
+			(SPEAR1340_MIPHY_PLL_RATIO_TOP(120))
+	#define SPEAR1340_PCIE_SATA_MIPHY_CFG_PCIE \
+			(SPEAR1340_MIPHY_OSC_BYPASS_EXT | \
+			SPEAR1340_MIPHY_PLL_RATIO_TOP(25))
+
+enum spear1340_miphy_mode {
+	SATA,
+	PCIE,
+};
+
+struct spear1340_miphy_priv {
+	/* phy mode: 0 for SATA 1 for PCIe */
+	enum spear1340_miphy_mode	mode;
+	/* regmap for any soc specific misc registers */
+	struct regmap			*misc;
+	/* phy struct pointer */
+	struct phy			*phy;
+};
+
+static int spear1340_miphy_sata_init(struct spear1340_miphy_priv *priv)
+{
+	regmap_update_bits(priv->misc, SPEAR1340_PCIE_SATA_CFG,
+			   SPEAR1340_PCIE_SATA_CFG_MASK,
+			   SPEAR1340_SATA_CFG_VAL);
+	regmap_update_bits(priv->misc, SPEAR1340_PCIE_MIPHY_CFG,
+			   SPEAR1340_PCIE_MIPHY_CFG_MASK,
+			   SPEAR1340_PCIE_SATA_MIPHY_CFG_SATA_25M_CRYSTAL_CLK);
+	/* Switch on sata power domain */
+	regmap_update_bits(priv->misc, SPEAR1340_PCM_CFG,
+			   SPEAR1340_PCM_CFG_SATA_POWER_EN,
+			   SPEAR1340_PCM_CFG_SATA_POWER_EN);
+	/* Wait for SATA power domain on */
+	msleep(20);
+
+	/* Disable PCIE SATA Controller reset */
+	regmap_update_bits(priv->misc, SPEAR1340_PERIP1_SW_RST,
+			   SPEAR1340_PERIP1_SW_RSATA, 0);
+	/* Wait for SATA reset de-assert completion */
+	msleep(20);
+
+	return 0;
+}
+
+static int spear1340_miphy_sata_exit(struct spear1340_miphy_priv *priv)
+{
+	regmap_update_bits(priv->misc, SPEAR1340_PCIE_SATA_CFG,
+			   SPEAR1340_PCIE_SATA_CFG_MASK, 0);
+	regmap_update_bits(priv->misc, SPEAR1340_PCIE_MIPHY_CFG,
+			   SPEAR1340_PCIE_MIPHY_CFG_MASK, 0);
+
+	/* Enable PCIE SATA Controller reset */
+	regmap_update_bits(priv->misc, SPEAR1340_PERIP1_SW_RST,
+			   SPEAR1340_PERIP1_SW_RSATA,
+			   SPEAR1340_PERIP1_SW_RSATA);
+	/* Wait for SATA power domain off */
+	msleep(20);
+	/* Switch off sata power domain */
+	regmap_update_bits(priv->misc, SPEAR1340_PCM_CFG,
+			   SPEAR1340_PCM_CFG_SATA_POWER_EN, 0);
+	/* Wait for SATA reset assert completion */
+	msleep(20);
+
+	return 0;
+}
+
+static int spear1340_miphy_pcie_init(struct spear1340_miphy_priv *priv)
+{
+	regmap_update_bits(priv->misc, SPEAR1340_PCIE_MIPHY_CFG,
+			   SPEAR1340_PCIE_MIPHY_CFG_MASK,
+			   SPEAR1340_PCIE_SATA_MIPHY_CFG_PCIE);
+	regmap_update_bits(priv->misc, SPEAR1340_PCIE_SATA_CFG,
+			   SPEAR1340_PCIE_SATA_CFG_MASK,
+			   SPEAR1340_PCIE_CFG_VAL);
+
+	return 0;
+}
+
+static int spear1340_miphy_pcie_exit(struct spear1340_miphy_priv *priv)
+{
+	regmap_update_bits(priv->misc, SPEAR1340_PCIE_MIPHY_CFG,
+			   SPEAR1340_PCIE_MIPHY_CFG_MASK, 0);
+	regmap_update_bits(priv->misc, SPEAR1340_PCIE_SATA_CFG,
+			   SPEAR1340_PCIE_SATA_CFG_MASK, 0);
+
+	return 0;
+}
+
+static int spear1340_miphy_init(struct phy *phy)
+{
+	struct spear1340_miphy_priv *priv = phy_get_drvdata(phy);
+	int ret = 0;
+
+	if (priv->mode == SATA)
+		ret = spear1340_miphy_sata_init(priv);
+	else if (priv->mode == PCIE)
+		ret = spear1340_miphy_pcie_init(priv);
+
+	return ret;
+}
+
+static int spear1340_miphy_exit(struct phy *phy)
+{
+	struct spear1340_miphy_priv *priv = phy_get_drvdata(phy);
+	int ret = 0;
+
+	if (priv->mode == SATA)
+		ret = spear1340_miphy_sata_exit(priv);
+	else if (priv->mode == PCIE)
+		ret = spear1340_miphy_pcie_exit(priv);
+
+	return ret;
+}
+
+static const struct of_device_id spear1340_miphy_of_match[] = {
+	{ .compatible = "st,spear1340-miphy" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, spear1340_miphy_of_match);
+
+static struct phy_ops spear1340_miphy_ops = {
+	.init = spear1340_miphy_init,
+	.exit = spear1340_miphy_exit,
+	.owner = THIS_MODULE,
+};
+
+#ifdef CONFIG_PM_SLEEP
+static int spear1340_miphy_suspend(struct device *dev)
+{
+	struct spear1340_miphy_priv *priv = dev_get_drvdata(dev);
+	int ret = 0;
+
+	if (priv->mode == SATA)
+		ret = spear1340_miphy_sata_exit(priv);
+
+	return ret;
+}
+
+static int spear1340_miphy_resume(struct device *dev)
+{
+	struct spear1340_miphy_priv *priv = dev_get_drvdata(dev);
+	int ret = 0;
+
+	if (priv->mode == SATA)
+		ret = spear1340_miphy_sata_init(priv);
+
+	return ret;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(spear1340_miphy_pm_ops, spear1340_miphy_suspend,
+			 spear1340_miphy_resume);
+
+static struct phy *spear1340_miphy_xlate(struct device *dev,
+					 struct of_phandle_args *args)
+{
+	struct spear1340_miphy_priv *priv = dev_get_drvdata(dev);
+
+	if (args->args_count < 1) {
+		dev_err(dev, "DT did not pass correct no of args\n");
+		return NULL;
+	}
+
+	priv->mode = args->args[0];
+
+	if (priv->mode != SATA && priv->mode != PCIE) {
+		dev_err(dev, "DT did not pass correct phy mode\n");
+		return NULL;
+	}
+
+	return priv->phy;
+}
+
+static int spear1340_miphy_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct spear1340_miphy_priv *priv;
+	struct phy_provider *phy_provider;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv) {
+		dev_err(dev, "can't alloc spear1340_miphy private date memory\n");
+		return -ENOMEM;
+	}
+
+	priv->misc =
+		syscon_regmap_lookup_by_phandle(dev->of_node, "misc");
+	if (IS_ERR(priv->misc)) {
+		dev_err(dev, "failed to find misc regmap\n");
+		return PTR_ERR(priv->misc);
+	}
+
+	priv->phy = devm_phy_create(dev, &spear1340_miphy_ops, NULL);
+	if (IS_ERR(priv->phy)) {
+		dev_err(dev, "failed to create SATA PCIe PHY\n");
+		return PTR_ERR(priv->phy);
+	}
+
+	dev_set_drvdata(dev, priv);
+	phy_set_drvdata(priv->phy, priv);
+
+	phy_provider =
+		devm_of_phy_provider_register(dev, spear1340_miphy_xlate);
+	if (IS_ERR(phy_provider)) {
+		dev_err(dev, "failed to register phy provider\n");
+		return PTR_ERR(phy_provider);
+	}
+
+	return 0;
+}
+
+static struct platform_driver spear1340_miphy_driver = {
+	.probe		= spear1340_miphy_probe,
+	.driver = {
+		.name = "spear1340-miphy",
+		.owner = THIS_MODULE,
+		.pm = &spear1340_miphy_pm_ops,
+		.of_match_table = of_match_ptr(spear1340_miphy_of_match),
+	},
+};
+
+static int __init spear1340_miphy_phy_init(void)
+{
+	return platform_driver_register(&spear1340_miphy_driver);
+}
+module_init(spear1340_miphy_phy_init);
+
+static void __exit spear1340_miphy_phy_exit(void)
+{
+	platform_driver_unregister(&spear1340_miphy_driver);
+}
+module_exit(spear1340_miphy_phy_exit);
+
+MODULE_DESCRIPTION("ST SPEAR1340-MIPHY driver");
+MODULE_AUTHOR("Pratyush Anand <pratyush.anand@st.com>");
+MODULE_LICENSE("GPL v2");