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, 274 insertions, 0 deletions

diff --git a/drivers/phy/phy-spear1310-miphy.c b/drivers/phy/phy-spear1310-miphy.c
new file mode 100644
index 000000000000..c58c869d57e0
--- /dev/null
+++ b/drivers/phy/phy-spear1310-miphy.c
@@ -0,0 +1,274 @@
+/*
+ * ST SPEAr1310-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>
+
+/* SPEAr1310 Registers */
+#define SPEAR1310_PCIE_SATA_CFG                 0x3A4
+        #define SPEAR1310_PCIE_SATA2_SEL_PCIE           (0 << 31)
+        #define SPEAR1310_PCIE_SATA1_SEL_PCIE           (0 << 30)
+        #define SPEAR1310_PCIE_SATA0_SEL_PCIE           (0 << 29)
+        #define SPEAR1310_PCIE_SATA2_SEL_SATA           BIT(31)
+        #define SPEAR1310_PCIE_SATA1_SEL_SATA           BIT(30)
+        #define SPEAR1310_PCIE_SATA0_SEL_SATA           BIT(29)
+        #define SPEAR1310_SATA2_CFG_TX_CLK_EN           BIT(27)
+        #define SPEAR1310_SATA2_CFG_RX_CLK_EN           BIT(26)
+        #define SPEAR1310_SATA2_CFG_POWERUP_RESET       BIT(25)
+        #define SPEAR1310_SATA2_CFG_PM_CLK_EN           BIT(24)
+        #define SPEAR1310_SATA1_CFG_TX_CLK_EN           BIT(23)
+        #define SPEAR1310_SATA1_CFG_RX_CLK_EN           BIT(22)
+        #define SPEAR1310_SATA1_CFG_POWERUP_RESET       BIT(21)
+        #define SPEAR1310_SATA1_CFG_PM_CLK_EN           BIT(20)
+        #define SPEAR1310_SATA0_CFG_TX_CLK_EN           BIT(19)
+        #define SPEAR1310_SATA0_CFG_RX_CLK_EN           BIT(18)
+        #define SPEAR1310_SATA0_CFG_POWERUP_RESET       BIT(17)
+        #define SPEAR1310_SATA0_CFG_PM_CLK_EN           BIT(16)
+        #define SPEAR1310_PCIE2_CFG_DEVICE_PRESENT      BIT(11)
+        #define SPEAR1310_PCIE2_CFG_POWERUP_RESET       BIT(10)
+        #define SPEAR1310_PCIE2_CFG_CORE_CLK_EN         BIT(9)
+        #define SPEAR1310_PCIE2_CFG_AUX_CLK_EN          BIT(8)
+        #define SPEAR1310_PCIE1_CFG_DEVICE_PRESENT      BIT(7)
+        #define SPEAR1310_PCIE1_CFG_POWERUP_RESET       BIT(6)
+        #define SPEAR1310_PCIE1_CFG_CORE_CLK_EN         BIT(5)
+        #define SPEAR1310_PCIE1_CFG_AUX_CLK_EN          BIT(4)
+        #define SPEAR1310_PCIE0_CFG_DEVICE_PRESENT      BIT(3)
+        #define SPEAR1310_PCIE0_CFG_POWERUP_RESET       BIT(2)
+        #define SPEAR1310_PCIE0_CFG_CORE_CLK_EN         BIT(1)
+        #define SPEAR1310_PCIE0_CFG_AUX_CLK_EN          BIT(0)
+
+        #define SPEAR1310_PCIE_CFG_MASK(x) ((0xF << (x * 4)) | BIT((x + 29)))
+        #define SPEAR1310_SATA_CFG_MASK(x) ((0xF << (x * 4 + 16)) | \
+                        BIT((x + 29)))
+        #define SPEAR1310_PCIE_CFG_VAL(x) \
+                        (SPEAR1310_PCIE_SATA##x##_SEL_PCIE | \
+                        SPEAR1310_PCIE##x##_CFG_AUX_CLK_EN | \
+                        SPEAR1310_PCIE##x##_CFG_CORE_CLK_EN | \
+                        SPEAR1310_PCIE##x##_CFG_POWERUP_RESET | \
+                        SPEAR1310_PCIE##x##_CFG_DEVICE_PRESENT)
+        #define SPEAR1310_SATA_CFG_VAL(x) \
+                        (SPEAR1310_PCIE_SATA##x##_SEL_SATA | \
+                        SPEAR1310_SATA##x##_CFG_PM_CLK_EN | \
+                        SPEAR1310_SATA##x##_CFG_POWERUP_RESET | \
+                        SPEAR1310_SATA##x##_CFG_RX_CLK_EN | \
+                        SPEAR1310_SATA##x##_CFG_TX_CLK_EN)
+
+#define SPEAR1310_PCIE_MIPHY_CFG_1              0x3A8
+        #define SPEAR1310_MIPHY_DUAL_OSC_BYPASS_EXT     BIT(31)
+        #define SPEAR1310_MIPHY_DUAL_CLK_REF_DIV2       BIT(28)
+        #define SPEAR1310_MIPHY_DUAL_PLL_RATIO_TOP(x)   (x << 16)
+        #define SPEAR1310_MIPHY_SINGLE_OSC_BYPASS_EXT   BIT(15)
+        #define SPEAR1310_MIPHY_SINGLE_CLK_REF_DIV2     BIT(12)
+        #define SPEAR1310_MIPHY_SINGLE_PLL_RATIO_TOP(x) (x << 0)
+        #define SPEAR1310_PCIE_SATA_MIPHY_CFG_SATA_MASK (0xFFFF)
+        #define SPEAR1310_PCIE_SATA_MIPHY_CFG_PCIE_MASK (0xFFFF << 16)
+        #define SPEAR1310_PCIE_SATA_MIPHY_CFG_SATA \
+                        (SPEAR1310_MIPHY_DUAL_OSC_BYPASS_EXT | \
+                        SPEAR1310_MIPHY_DUAL_CLK_REF_DIV2 | \
+                        SPEAR1310_MIPHY_DUAL_PLL_RATIO_TOP(60) | \
+                        SPEAR1310_MIPHY_SINGLE_OSC_BYPASS_EXT | \
+                        SPEAR1310_MIPHY_SINGLE_CLK_REF_DIV2 | \
+                        SPEAR1310_MIPHY_SINGLE_PLL_RATIO_TOP(60))
+        #define SPEAR1310_PCIE_SATA_MIPHY_CFG_SATA_25M_CRYSTAL_CLK \
+                        (SPEAR1310_MIPHY_SINGLE_PLL_RATIO_TOP(120))
+        #define SPEAR1310_PCIE_SATA_MIPHY_CFG_PCIE \
+                        (SPEAR1310_MIPHY_DUAL_OSC_BYPASS_EXT | \
+                        SPEAR1310_MIPHY_DUAL_PLL_RATIO_TOP(25) | \
+                        SPEAR1310_MIPHY_SINGLE_OSC_BYPASS_EXT | \
+                        SPEAR1310_MIPHY_SINGLE_PLL_RATIO_TOP(25))
+
+#define SPEAR1310_PCIE_MIPHY_CFG_2              0x3AC
+
+enum spear1310_miphy_mode {
+        SATA,
+        PCIE,
+};
+
+struct spear1310_miphy_priv {
+        /* instance id of this phy */
+        u32                             id;
+        /* phy mode: 0 for SATA 1 for PCIe */
+        enum spear1310_miphy_mode       mode;
+        /* regmap for any soc specific misc registers */
+        struct regmap                   *misc;
+        /* phy struct pointer */
+        struct phy                      *phy;
+};
+
+static int spear1310_miphy_pcie_init(struct spear1310_miphy_priv *priv)
+{
+        u32 val;
+
+        regmap_update_bits(priv->misc, SPEAR1310_PCIE_MIPHY_CFG_1,
+                           SPEAR1310_PCIE_SATA_MIPHY_CFG_PCIE_MASK,
+                           SPEAR1310_PCIE_SATA_MIPHY_CFG_PCIE);
+
+        switch (priv->id) {
+        case 0:
+                val = SPEAR1310_PCIE_CFG_VAL(0);
+                break;
+        case 1:
+                val = SPEAR1310_PCIE_CFG_VAL(1);
+                break;
+        case 2:
+                val = SPEAR1310_PCIE_CFG_VAL(2);
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        regmap_update_bits(priv->misc, SPEAR1310_PCIE_SATA_CFG,
+                           SPEAR1310_PCIE_CFG_MASK(priv->id), val);
+
+        return 0;
+}
+
+static int spear1310_miphy_pcie_exit(struct spear1310_miphy_priv *priv)
+{
+        regmap_update_bits(priv->misc, SPEAR1310_PCIE_SATA_CFG,
+                           SPEAR1310_PCIE_CFG_MASK(priv->id), 0);
+
+        regmap_update_bits(priv->misc, SPEAR1310_PCIE_MIPHY_CFG_1,
+                           SPEAR1310_PCIE_SATA_MIPHY_CFG_PCIE_MASK, 0);
+
+        return 0;
+}
+
+static int spear1310_miphy_init(struct phy *phy)
+{
+        struct spear1310_miphy_priv *priv = phy_get_drvdata(phy);
+        int ret = 0;
+
+        if (priv->mode == PCIE)
+                ret = spear1310_miphy_pcie_init(priv);
+
+        return ret;
+}
+
+static int spear1310_miphy_exit(struct phy *phy)
+{
+        struct spear1310_miphy_priv *priv = phy_get_drvdata(phy);
+        int ret = 0;
+
+        if (priv->mode == PCIE)
+                ret = spear1310_miphy_pcie_exit(priv);
+
+        return ret;
+}
+
+static const struct of_device_id spear1310_miphy_of_match[] = {
+        { .compatible = "st,spear1310-miphy" },
+        { },
+};
+MODULE_DEVICE_TABLE(of, spear1310_miphy_of_match);
+
+static struct phy_ops spear1310_miphy_ops = {
+        .init = spear1310_miphy_init,
+        .exit = spear1310_miphy_exit,
+        .owner = THIS_MODULE,
+};
+
+static struct phy *spear1310_miphy_xlate(struct device *dev,
+                                         struct of_phandle_args *args)
+{
+        struct spear1310_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 spear1310_miphy_probe(struct platform_device *pdev)
+{
+        struct device *dev = &pdev->dev;
+        struct spear1310_miphy_priv *priv;
+        struct phy_provider *phy_provider;
+
+        priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+        if (!priv) {
+                dev_err(dev, "can't alloc spear1310_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);
+        }
+
+        if (of_property_read_u32(dev->of_node, "phy-id", &priv->id)) {
+                dev_err(dev, "failed to find phy id\n");
+                return -EINVAL;
+        }
+
+        priv->phy = devm_phy_create(dev, &spear1310_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, spear1310_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 spear1310_miphy_driver = {
+        .probe          = spear1310_miphy_probe,
+        .driver = {
+                .name = "spear1310-miphy",
+                .owner = THIS_MODULE,
+                .of_match_table = of_match_ptr(spear1310_miphy_of_match),
+        },
+};
+
+static int __init spear1310_miphy_phy_init(void)
+{
+        return platform_driver_register(&spear1310_miphy_driver);
+}
+module_init(spear1310_miphy_phy_init);
+
+static void __exit spear1310_miphy_phy_exit(void)
+{
+        platform_driver_unregister(&spear1310_miphy_driver);
+}
+module_exit(spear1310_miphy_phy_exit);
+
+MODULE_DESCRIPTION("ST SPEAR1310-MIPHY driver");
+MODULE_AUTHOR("Pratyush Anand <pratyush.anand@st.com>");
+MODULE_LICENSE("GPL v2");