drivers/phy/phy-qcom-ipq806x-sata.c

   1 /*
   2  * Copyright (c) 2014, The Linux Foundation. All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 and
   6  * only version 2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <linux/io.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/of.h>
  18 #include <linux/of_address.h>
  19 #include <linux/time.h>
  20 #include <linux/delay.h>
  21 #include <linux/clk.h>
  22 #include <linux/slab.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/phy/phy.h>
  25
  26 struct qcom_ipq806x_sata_phy {
  27         void __iomem *mmio;
  28         struct clk *cfg_clk;
  29         struct device *dev;
  30 };
  31
  32 #define __set(v, a, b)  (((v) << (b)) & GENMASK(a, b))
  33
  34 #define SATA_PHY_P0_PARAM0              0x200
  35 #define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3(x)        __set(x, 17, 12)
  36 #define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3_MASK      GENMASK(17, 12)
  37 #define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN2(x)        __set(x, 11, 6)
  38 #define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN2_MASK      GENMASK(11, 6)
  39 #define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN1(x)        __set(x, 5, 0)
  40 #define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN1_MASK      GENMASK(5, 0)
  41
  42 #define SATA_PHY_P0_PARAM1              0x204
  43 #define SATA_PHY_P0_PARAM1_RESERVED_BITS31_21(x)        __set(x, 31, 21)
  44 #define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3(x)      __set(x, 20, 14)
  45 #define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3_MASK    GENMASK(20, 14)
  46 #define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2(x)      __set(x, 13, 7)
  47 #define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2_MASK    GENMASK(13, 7)
  48 #define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1(x)      __set(x, 6, 0)
  49 #define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1_MASK    GENMASK(6, 0)
  50
  51 #define SATA_PHY_P0_PARAM2              0x208
  52 #define SATA_PHY_P0_PARAM2_RX_EQ(x)     __set(x, 20, 18)
  53 #define SATA_PHY_P0_PARAM2_RX_EQ_MASK   GENMASK(20, 18)
  54
  55 #define SATA_PHY_P0_PARAM3              0x20C
  56 #define SATA_PHY_SSC_EN                 0x8
  57 #define SATA_PHY_P0_PARAM4              0x210
  58 #define SATA_PHY_REF_SSP_EN             0x2
  59 #define SATA_PHY_RESET                  0x1
  60
  61 static int qcom_ipq806x_sata_phy_init(struct phy *generic_phy)
  62 {
  63         struct qcom_ipq806x_sata_phy *phy = phy_get_drvdata(generic_phy);
  64         u32 reg;
  65
  66         /* Setting SSC_EN to 1 */
  67         reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM3);
  68         reg = reg | SATA_PHY_SSC_EN;
  69         writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM3);
  70
  71         reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM0) &
  72                         ~(SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3_MASK |
  73                           SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN2_MASK |
  74                           SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN1_MASK);
  75         reg |= SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3(0xf);
  76         writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM0);
  77
  78         reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM1) &
  79                         ~(SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3_MASK |
  80                           SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2_MASK |
  81                           SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1_MASK);
  82         reg |= SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3(0x55) |
  83                 SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2(0x55) |
  84                 SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1(0x55);
  85         writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM1);
  86
  87         reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM2) &
  88                 ~SATA_PHY_P0_PARAM2_RX_EQ_MASK;
  89         reg |= SATA_PHY_P0_PARAM2_RX_EQ(0x3);
  90         writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM2);
  91
  92         /* Setting PHY_RESET to 1 */
  93         reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
  94         reg = reg | SATA_PHY_RESET;
  95         writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
  96
  97         /* Setting REF_SSP_EN to 1 */
  98         reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
  99         reg = reg | SATA_PHY_REF_SSP_EN | SATA_PHY_RESET;
 100         writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
 101
 102         /* make sure all changes complete before we let the PHY out of reset */
 103         mb();
 104
 105         /* sleep for max. 50us more to combine processor wakeups */
 106         usleep_range(20, 20 + 50);
 107
 108         /* Clearing PHY_RESET to 0 */
 109         reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
 110         reg = reg & ~SATA_PHY_RESET;
 111         writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
 112
 113         return 0;
 114 }
 115
 116 static int qcom_ipq806x_sata_phy_exit(struct phy *generic_phy)
 117 {
 118         struct qcom_ipq806x_sata_phy *phy = phy_get_drvdata(generic_phy);
 119         u32 reg;
 120
 121         /* Setting PHY_RESET to 1 */
 122         reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
 123         reg = reg | SATA_PHY_RESET;
 124         writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
 125
 126         return 0;
 127 }
 128
 129 static const struct phy_ops qcom_ipq806x_sata_phy_ops = {
 130         .init           = qcom_ipq806x_sata_phy_init,
 131         .exit           = qcom_ipq806x_sata_phy_exit,
 132         .owner          = THIS_MODULE,
 133 };
 134
 135 static int qcom_ipq806x_sata_phy_probe(struct platform_device *pdev)
 136 {
 137         struct qcom_ipq806x_sata_phy *phy;
 138         struct device *dev = &pdev->dev;
 139         struct resource *res;
 140         struct phy_provider *phy_provider;
 141         struct phy *generic_phy;
 142         int ret;
 143
 144         phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
 145         if (!phy)
 146                 return -ENOMEM;
 147
 148         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 149         phy->mmio = devm_ioremap_resource(dev, res);
 150         if (IS_ERR(phy->mmio))
 151                 return PTR_ERR(phy->mmio);
 152
 153         generic_phy = devm_phy_create(dev, NULL, &qcom_ipq806x_sata_phy_ops);
 154         if (IS_ERR(generic_phy)) {
 155                 dev_err(dev, "%s: failed to create phy\n", __func__);
 156                 return PTR_ERR(generic_phy);
 157         }
 158
 159         phy->dev = dev;
 160         phy_set_drvdata(generic_phy, phy);
 161         platform_set_drvdata(pdev, phy);
 162
 163         phy->cfg_clk = devm_clk_get(dev, "cfg");
 164         if (IS_ERR(phy->cfg_clk)) {
 165                 dev_err(dev, "Failed to get sata cfg clock\n");
 166                 return PTR_ERR(phy->cfg_clk);
 167         }
 168
 169         ret = clk_prepare_enable(phy->cfg_clk);
 170         if (ret)
 171                 return ret;
 172
 173         phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
 174         if (IS_ERR(phy_provider)) {
 175                 clk_disable_unprepare(phy->cfg_clk);
 176                 dev_err(dev, "%s: failed to register phy\n", __func__);
 177                 return PTR_ERR(phy_provider);
 178         }
 179
 180         return 0;
 181 }
 182
 183 static int qcom_ipq806x_sata_phy_remove(struct platform_device *pdev)
 184 {
 185         struct qcom_ipq806x_sata_phy *phy = platform_get_drvdata(pdev);
 186
 187         clk_disable_unprepare(phy->cfg_clk);
 188
 189         return 0;
 190 }
 191
 192 static const struct of_device_id qcom_ipq806x_sata_phy_of_match[] = {
 193         { .compatible = "qcom,ipq806x-sata-phy" },
 194         { },
 195 };
 196 MODULE_DEVICE_TABLE(of, qcom_ipq806x_sata_phy_of_match);
 197
 198 static struct platform_driver qcom_ipq806x_sata_phy_driver = {
 199         .probe  = qcom_ipq806x_sata_phy_probe,
 200         .remove = qcom_ipq806x_sata_phy_remove,
 201         .driver = {
 202                 .name   = "qcom-ipq806x-sata-phy",
 203                 .of_match_table = qcom_ipq806x_sata_phy_of_match,
 204         }
 205 };
 206 module_platform_driver(qcom_ipq806x_sata_phy_driver);
 207
 208 MODULE_DESCRIPTION("QCOM IPQ806x SATA PHY driver");
 209 MODULE_LICENSE("GPL v2");