phy: add Broadcom SATA3 PHY driver for Broadcom STB SoCs

Supports up to two ports which can each be powered on/off and configured
independently.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

3 files changed, 226 insertions, 0 deletions

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index a53bd5b52df9..36788b6f0220 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -309,4 +309,13 @@ config PHY_QCOM_UFS
         help
           Support for UFS PHY on QCOM chipsets.
 
+config PHY_BRCMSTB_SATA
+        tristate "Broadcom STB SATA PHY driver"
+        depends on ARCH_BRCMSTB
+        depends on OF
+        select GENERIC_PHY
+        help
+          Enable this to support the SATA3 PHY on 28nm Broadcom STB SoCs.
+          Likely useful only with CONFIG_SATA_BRCMSTB enabled.
+
 endmenu
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index f12625178780..c61f3fdd191e 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -40,3 +40,4 @@ obj-$(CONFIG_PHY_STIH41X_USB)		+= phy-stih41x-usb.o
 obj-$(CONFIG_PHY_QCOM_UFS)      += phy-qcom-ufs.o
 obj-$(CONFIG_PHY_QCOM_UFS)      += phy-qcom-ufs-qmp-20nm.o
 obj-$(CONFIG_PHY_QCOM_UFS)      += phy-qcom-ufs-qmp-14nm.o
+obj-$(CONFIG_PHY_BRCMSTB_SATA)          += phy-brcmstb-sata.o
diff --git a/drivers/phy/phy-brcmstb-sata.c b/drivers/phy/phy-brcmstb-sata.c
new file mode 100644
index 000000000000..b7e303d28caf
--- /dev/null
+++ b/drivers/phy/phy-brcmstb-sata.c
@@ -0,0 +1,216 @@
+/*
+ * Broadcom SATA3 AHCI Controller PHY Driver
+ *
+ * Copyright © 2009-2015 Broadcom Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that 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/device.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+
+#define SATA_MDIO_BANK_OFFSET                           0x23c
+#define SATA_MDIO_REG_OFFSET(ofs)                       ((ofs) * 4)
+#define SATA_MDIO_REG_SPACE_SIZE                        0x1000
+#define SATA_MDIO_REG_LENGTH                            0x1f00
+
+#define MAX_PORTS                                       2
+
+/* Register offset between PHYs in PCB space */
+#define SATA_MDIO_REG_SPACE_SIZE                        0x1000
+
+struct brcm_sata_port {
+        int portnum;
+        struct phy *phy;
+        struct brcm_sata_phy *phy_priv;
+        bool ssc_en;
+};
+
+struct brcm_sata_phy {
+        struct device *dev;
+        void __iomem *phy_base;
+
+        struct brcm_sata_port phys[MAX_PORTS];
+};
+
+enum sata_mdio_phy_regs_28nm {
+        PLL_REG_BANK_0                          = 0x50,
+        PLL_REG_BANK_0_PLLCONTROL_0             = 0x81,
+
+        TXPMD_REG_BANK                          = 0x1a0,
+        TXPMD_CONTROL1                          = 0x81,
+        TXPMD_CONTROL1_TX_SSC_EN_FRC            = BIT(0),
+        TXPMD_CONTROL1_TX_SSC_EN_FRC_VAL        = BIT(1),
+        TXPMD_TX_FREQ_CTRL_CONTROL1             = 0x82,
+        TXPMD_TX_FREQ_CTRL_CONTROL2             = 0x83,
+        TXPMD_TX_FREQ_CTRL_CONTROL2_FMIN_MASK   = 0x3ff,
+        TXPMD_TX_FREQ_CTRL_CONTROL3             = 0x84,
+        TXPMD_TX_FREQ_CTRL_CONTROL3_FMAX_MASK   = 0x3ff,
+};
+
+static inline void __iomem *brcm_sata_phy_base(struct brcm_sata_port *port)
+{
+        struct brcm_sata_phy *priv = port->phy_priv;
+
+        return priv->phy_base + (port->portnum * SATA_MDIO_REG_SPACE_SIZE);
+}
+
+static void brcm_sata_mdio_wr(void __iomem *addr, u32 bank, u32 ofs,
+                              u32 msk, u32 value)
+{
+        u32 tmp;
+
+        writel(bank, addr + SATA_MDIO_BANK_OFFSET);
+        tmp = readl(addr + SATA_MDIO_REG_OFFSET(ofs));
+        tmp = (tmp & msk) | value;
+        writel(tmp, addr + SATA_MDIO_REG_OFFSET(ofs));
+}
+
+/* These defaults were characterized by H/W group */
+#define FMIN_VAL_DEFAULT        0x3df
+#define FMAX_VAL_DEFAULT        0x3df
+#define FMAX_VAL_SSC            0x83
+
+static void brcm_sata_cfg_ssc_28nm(struct brcm_sata_port *port)
+{
+        void __iomem *base = brcm_sata_phy_base(port);
+        struct brcm_sata_phy *priv = port->phy_priv;
+        u32 tmp;
+
+        /* override the TX spread spectrum setting */
+        tmp = TXPMD_CONTROL1_TX_SSC_EN_FRC_VAL | TXPMD_CONTROL1_TX_SSC_EN_FRC;
+        brcm_sata_mdio_wr(base, TXPMD_REG_BANK, TXPMD_CONTROL1, ~tmp, tmp);
+
+        /* set fixed min freq */
+        brcm_sata_mdio_wr(base, TXPMD_REG_BANK, TXPMD_TX_FREQ_CTRL_CONTROL2,
+                          ~TXPMD_TX_FREQ_CTRL_CONTROL2_FMIN_MASK,
+                          FMIN_VAL_DEFAULT);
+
+        /* set fixed max freq depending on SSC config */
+        if (port->ssc_en) {
+                dev_info(priv->dev, "enabling SSC on port %d\n", port->portnum);
+                tmp = FMAX_VAL_SSC;
+        } else {
+                tmp = FMAX_VAL_DEFAULT;
+        }
+
+        brcm_sata_mdio_wr(base, TXPMD_REG_BANK, TXPMD_TX_FREQ_CTRL_CONTROL3,
+                          ~TXPMD_TX_FREQ_CTRL_CONTROL3_FMAX_MASK, tmp);
+}
+
+static int brcm_sata_phy_init(struct phy *phy)
+{
+        struct brcm_sata_port *port = phy_get_drvdata(phy);
+
+        brcm_sata_cfg_ssc_28nm(port);
+
+        return 0;
+}
+
+static struct phy_ops phy_ops_28nm = {
+        .init           = brcm_sata_phy_init,
+        .owner          = THIS_MODULE,
+};
+
+static const struct of_device_id brcm_sata_phy_of_match[] = {
+        { .compatible   = "brcm,bcm7445-sata-phy" },
+        {},
+};
+MODULE_DEVICE_TABLE(of, brcm_sata_phy_of_match);
+
+static int brcm_sata_phy_probe(struct platform_device *pdev)
+{
+        struct device *dev = &pdev->dev;
+        struct device_node *dn = dev->of_node, *child;
+        struct brcm_sata_phy *priv;
+        struct resource *res;
+        struct phy_provider *provider;
+        int count = 0;
+
+        if (of_get_child_count(dn) == 0)
+                return -ENODEV;
+
+        priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+        if (!priv)
+                return -ENOMEM;
+        dev_set_drvdata(dev, priv);
+        priv->dev = dev;
+
+        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "phy");
+        priv->phy_base = devm_ioremap_resource(dev, res);
+        if (IS_ERR(priv->phy_base))
+                return PTR_ERR(priv->phy_base);
+
+        for_each_available_child_of_node(dn, child) {
+                unsigned int id;
+                struct brcm_sata_port *port;
+
+                if (of_property_read_u32(child, "reg", &id)) {
+                        dev_err(dev, "missing reg property in node %s\n",
+                                        child->name);
+                        return -EINVAL;
+                }
+
+                if (id >= MAX_PORTS) {
+                        dev_err(dev, "invalid reg: %u\n", id);
+                        return -EINVAL;
+                }
+                if (priv->phys[id].phy) {
+                        dev_err(dev, "already registered port %u\n", id);
+                        return -EINVAL;
+                }
+
+                port = &priv->phys[id];
+                port->portnum = id;
+                port->phy_priv = priv;
+                port->phy = devm_phy_create(dev, child, &phy_ops_28nm);
+                port->ssc_en = of_property_read_bool(child, "brcm,enable-ssc");
+                if (IS_ERR(port->phy)) {
+                        dev_err(dev, "failed to create PHY\n");
+                        return PTR_ERR(port->phy);
+                }
+
+                phy_set_drvdata(port->phy, port);
+                count++;
+        }
+
+        provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+        if (IS_ERR(provider)) {
+                dev_err(dev, "could not register PHY provider\n");
+                return PTR_ERR(provider);
+        }
+
+        dev_info(dev, "registered %d port(s)\n", count);
+
+        return 0;
+}
+
+static struct platform_driver brcm_sata_phy_driver = {
+        .probe  = brcm_sata_phy_probe,
+        .driver = {
+                .of_match_table = brcm_sata_phy_of_match,
+                .name           = "brcmstb-sata-phy",
+        }
+};
+module_platform_driver(brcm_sata_phy_driver);
+
+MODULE_DESCRIPTION("Broadcom STB SATA PHY driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Marc Carino");
+MODULE_AUTHOR("Brian Norris");
+MODULE_ALIAS("platform:phy-brcmstb-sata");