drivers/phy/phy-brcmstb-sata.c

   1 /*
   2  * Broadcom SATA3 AHCI Controller PHY Driver
   3  *
   4  * Copyright © 2009-2015 Broadcom Corporation
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2, or (at your option)
   9  * any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  */
  16
  17 #include <linux/device.h>
  18 #include <linux/init.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/io.h>
  21 #include <linux/kernel.h>
  22 #include <linux/module.h>
  23 #include <linux/of.h>
  24 #include <linux/phy/phy.h>
  25 #include <linux/platform_device.h>
  26
  27 #define SATA_MDIO_BANK_OFFSET                           0x23c
  28 #define SATA_MDIO_REG_OFFSET(ofs)                       ((ofs) * 4)
  29 #define SATA_MDIO_REG_SPACE_SIZE                        0x1000
  30 #define SATA_MDIO_REG_LENGTH                            0x1f00
  31
  32 #define MAX_PORTS                                       2
  33
  34 /* Register offset between PHYs in PCB space */
  35 #define SATA_MDIO_REG_SPACE_SIZE                        0x1000
  36
  37 struct brcm_sata_port {
  38         int portnum;
  39         struct phy *phy;
  40         struct brcm_sata_phy *phy_priv;
  41         bool ssc_en;
  42 };
  43
  44 struct brcm_sata_phy {
  45         struct device *dev;
  46         void __iomem *phy_base;
  47
  48         struct brcm_sata_port phys[MAX_PORTS];
  49 };
  50
  51 enum sata_mdio_phy_regs_28nm {
  52         PLL_REG_BANK_0                          = 0x50,
  53         PLL_REG_BANK_0_PLLCONTROL_0             = 0x81,
  54
  55         TXPMD_REG_BANK                          = 0x1a0,
  56         TXPMD_CONTROL1                          = 0x81,
  57         TXPMD_CONTROL1_TX_SSC_EN_FRC            = BIT(0),
  58         TXPMD_CONTROL1_TX_SSC_EN_FRC_VAL        = BIT(1),
  59         TXPMD_TX_FREQ_CTRL_CONTROL1             = 0x82,
  60         TXPMD_TX_FREQ_CTRL_CONTROL2             = 0x83,
  61         TXPMD_TX_FREQ_CTRL_CONTROL2_FMIN_MASK   = 0x3ff,
  62         TXPMD_TX_FREQ_CTRL_CONTROL3             = 0x84,
  63         TXPMD_TX_FREQ_CTRL_CONTROL3_FMAX_MASK   = 0x3ff,
  64 };
  65
  66 static inline void __iomem *brcm_sata_phy_base(struct brcm_sata_port *port)
  67 {
  68         struct brcm_sata_phy *priv = port->phy_priv;
  69
  70         return priv->phy_base + (port->portnum * SATA_MDIO_REG_SPACE_SIZE);
  71 }
  72
  73 static void brcm_sata_mdio_wr(void __iomem *addr, u32 bank, u32 ofs,
  74                               u32 msk, u32 value)
  75 {
  76         u32 tmp;
  77
  78         writel(bank, addr + SATA_MDIO_BANK_OFFSET);
  79         tmp = readl(addr + SATA_MDIO_REG_OFFSET(ofs));
  80         tmp = (tmp & msk) | value;
  81         writel(tmp, addr + SATA_MDIO_REG_OFFSET(ofs));
  82 }
  83
  84 /* These defaults were characterized by H/W group */
  85 #define FMIN_VAL_DEFAULT        0x3df
  86 #define FMAX_VAL_DEFAULT        0x3df
  87 #define FMAX_VAL_SSC            0x83
  88
  89 static void brcm_sata_cfg_ssc_28nm(struct brcm_sata_port *port)
  90 {
  91         void __iomem *base = brcm_sata_phy_base(port);
  92         struct brcm_sata_phy *priv = port->phy_priv;
  93         u32 tmp;
  94
  95         /* override the TX spread spectrum setting */
  96         tmp = TXPMD_CONTROL1_TX_SSC_EN_FRC_VAL | TXPMD_CONTROL1_TX_SSC_EN_FRC;
  97         brcm_sata_mdio_wr(base, TXPMD_REG_BANK, TXPMD_CONTROL1, ~tmp, tmp);
  98
  99         /* set fixed min freq */
 100         brcm_sata_mdio_wr(base, TXPMD_REG_BANK, TXPMD_TX_FREQ_CTRL_CONTROL2,
 101                           ~TXPMD_TX_FREQ_CTRL_CONTROL2_FMIN_MASK,
 102                           FMIN_VAL_DEFAULT);
 103
 104         /* set fixed max freq depending on SSC config */
 105         if (port->ssc_en) {
 106                 dev_info(priv->dev, "enabling SSC on port %d\n", port->portnum);
 107                 tmp = FMAX_VAL_SSC;
 108         } else {
 109                 tmp = FMAX_VAL_DEFAULT;
 110         }
 111
 112         brcm_sata_mdio_wr(base, TXPMD_REG_BANK, TXPMD_TX_FREQ_CTRL_CONTROL3,
 113                           ~TXPMD_TX_FREQ_CTRL_CONTROL3_FMAX_MASK, tmp);
 114 }
 115
 116 static int brcm_sata_phy_init(struct phy *phy)
 117 {
 118         struct brcm_sata_port *port = phy_get_drvdata(phy);
 119
 120         brcm_sata_cfg_ssc_28nm(port);
 121
 122         return 0;
 123 }
 124
 125 static const struct phy_ops phy_ops_28nm = {
 126         .init           = brcm_sata_phy_init,
 127         .owner          = THIS_MODULE,
 128 };
 129
 130 static const struct of_device_id brcm_sata_phy_of_match[] = {
 131         { .compatible   = "brcm,bcm7445-sata-phy" },
 132         {},
 133 };
 134 MODULE_DEVICE_TABLE(of, brcm_sata_phy_of_match);
 135
 136 static int brcm_sata_phy_probe(struct platform_device *pdev)
 137 {
 138         struct device *dev = &pdev->dev;
 139         struct device_node *dn = dev->of_node, *child;
 140         struct brcm_sata_phy *priv;
 141         struct resource *res;
 142         struct phy_provider *provider;
 143         int count = 0;
 144
 145         if (of_get_child_count(dn) == 0)
 146                 return -ENODEV;
 147
 148         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 149         if (!priv)
 150                 return -ENOMEM;
 151         dev_set_drvdata(dev, priv);
 152         priv->dev = dev;
 153
 154         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "phy");
 155         priv->phy_base = devm_ioremap_resource(dev, res);
 156         if (IS_ERR(priv->phy_base))
 157                 return PTR_ERR(priv->phy_base);
 158
 159         for_each_available_child_of_node(dn, child) {
 160                 unsigned int id;
 161                 struct brcm_sata_port *port;
 162
 163                 if (of_property_read_u32(child, "reg", &id)) {
 164                         dev_err(dev, "missing reg property in node %s\n",
 165                                         child->name);
 166                         return -EINVAL;
 167                 }
 168
 169                 if (id >= MAX_PORTS) {
 170                         dev_err(dev, "invalid reg: %u\n", id);
 171                         return -EINVAL;
 172                 }
 173                 if (priv->phys[id].phy) {
 174                         dev_err(dev, "already registered port %u\n", id);
 175                         return -EINVAL;
 176                 }
 177
 178                 port = &priv->phys[id];
 179                 port->portnum = id;
 180                 port->phy_priv = priv;
 181                 port->phy = devm_phy_create(dev, child, &phy_ops_28nm);
 182                 port->ssc_en = of_property_read_bool(child, "brcm,enable-ssc");
 183                 if (IS_ERR(port->phy)) {
 184                         dev_err(dev, "failed to create PHY\n");
 185                         return PTR_ERR(port->phy);
 186                 }
 187
 188                 phy_set_drvdata(port->phy, port);
 189                 count++;
 190         }
 191
 192         provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
 193         if (IS_ERR(provider)) {
 194                 dev_err(dev, "could not register PHY provider\n");
 195                 return PTR_ERR(provider);
 196         }
 197
 198         dev_info(dev, "registered %d port(s)\n", count);
 199
 200         return 0;
 201 }
 202
 203 static struct platform_driver brcm_sata_phy_driver = {
 204         .probe  = brcm_sata_phy_probe,
 205         .driver = {
 206                 .of_match_table = brcm_sata_phy_of_match,
 207                 .name           = "brcmstb-sata-phy",
 208         }
 209 };
 210 module_platform_driver(brcm_sata_phy_driver);
 211
 212 MODULE_DESCRIPTION("Broadcom STB SATA PHY driver");
 213 MODULE_LICENSE("GPL");
 214 MODULE_AUTHOR("Marc Carino");
 215 MODULE_AUTHOR("Brian Norris");
 216 MODULE_ALIAS("platform:phy-brcmstb-sata");