/*
* Samsung EXYNOS SoC series PCIe PHY driver
*
* Phy provider for PCIe controller on Exynos SoC series
*
* Copyright (C) 2017 Samsung Electronics Co., Ltd.
* Jaehoon Chung <jh80.chung@samsung.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/delay.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/init.h>
#include <linux/mfd/syscon.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/phy/phy.h>
#include <linux/regmap.h>
/* PCIe Purple registers */
#define PCIE_PHY_GLOBAL_RESET 0x000
#define PCIE_PHY_COMMON_RESET 0x004
#define PCIE_PHY_CMN_REG 0x008
#define PCIE_PHY_MAC_RESET 0x00c
#define PCIE_PHY_PLL_LOCKED 0x010
#define PCIE_PHY_TRSVREG_RESET 0x020
#define PCIE_PHY_TRSV_RESET 0x024
/* PCIe PHY registers */
#define PCIE_PHY_IMPEDANCE 0x004
#define PCIE_PHY_PLL_DIV_0 0x008
#define PCIE_PHY_PLL_BIAS 0x00c
#define PCIE_PHY_DCC_FEEDBACK 0x014
#define PCIE_PHY_PLL_DIV_1 0x05c
#define PCIE_PHY_COMMON_POWER 0x064
#define PCIE_PHY_COMMON_PD_CMN BIT(3)
#define PCIE_PHY_TRSV0_EMP_LVL 0x084
#define PCIE_PHY_TRSV0_DRV_LVL 0x088
#define PCIE_PHY_TRSV0_RXCDR 0x0ac
#define PCIE_PHY_TRSV0_POWER 0x0c4
#define PCIE_PHY_TRSV0_PD_TSV BIT(7)
#define PCIE_PHY_TRSV0_LVCC 0x0dc
#define PCIE_PHY_TRSV1_EMP_LVL 0x144
#define PCIE_PHY_TRSV1_RXCDR 0x16c
#define PCIE_PHY_TRSV1_POWER 0x184
#define PCIE_PHY_TRSV1_PD_TSV BIT(7)
#define PCIE_PHY_TRSV1_LVCC 0x19c
#define PCIE_PHY_TRSV2_EMP_LVL 0x204
#define PCIE_PHY_TRSV2_RXCDR 0x22c
#define PCIE_PHY_TRSV2_POWER 0x244
#define PCIE_PHY_TRSV2_PD_TSV BIT(7)
#define PCIE_PHY_TRSV2_LVCC 0x25c
#define PCIE_PHY_TRSV3_EMP_LVL 0x2c4
#define PCIE_PHY_TRSV3_RXCDR 0x2ec
#define PCIE_PHY_TRSV3_POWER 0x304
#define PCIE_PHY_TRSV3_PD_TSV BIT(7)
#define PCIE_PHY_TRSV3_LVCC 0x31c
struct exynos_pcie_phy_data {
const struct phy_ops *ops;
};
/* For Exynos pcie phy */
struct exynos_pcie_phy {
const struct exynos_pcie_phy_data *drv_data;
void __iomem *phy_base;
void __iomem *blk_base; /* For exynos5440 */
};
static void exynos_pcie_phy_writel(void __iomem *base, u32 val, u32 offset)
{
writel(val, base + offset);
}
static u32 exynos_pcie_phy_readl(void __iomem *base, u32 offset)
{
return readl(base + offset);
}
/* For Exynos5440 specific functions */
static int exynos5440_pcie_phy_init(struct phy *phy)
{
struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
/* DCC feedback control off */
exynos_pcie_phy_writel(ep->phy_base, 0x29, PCIE_PHY_DCC_FEEDBACK);
/* set TX/RX impedance */
exynos_pcie_phy_writel(ep->phy_base, 0xd5, PCIE_PHY_IMPEDANCE);
/* set 50Mhz PHY clock */
exynos_pcie_phy_writel(ep->phy_base, 0x14, PCIE_PHY_PLL_DIV_0);
exynos_pcie_phy_writel(ep->phy_base, 0x12, PCIE_PHY_PLL_DIV_1);
/* set TX Differential output for lane 0 */
exynos_pcie_phy_writel(ep->phy_base, 0x7f, PCIE_PHY_TRSV0_DRV_LVL);
/* set TX Pre-emphasis Level Control for lane 0 to minimum */
exynos_pcie_phy_writel(ep->phy_base, 0x0, PCIE_PHY_TRSV0_EMP_LVL);
/* set RX clock and data recovery bandwidth */
exynos_pcie_phy_writel(ep->phy_base, 0xe7, PCIE_PHY_PLL_BIAS);
exynos_pcie_phy_writel(ep->phy_base, 0x82, PCIE_PHY_TRSV0_RXCDR);
exynos_pcie_phy_writel(ep->phy_base, 0x82, PCIE_PHY_TRSV1_RXCDR);
exynos_pcie_phy_writel(ep->phy_base, 0x82, PCIE_PHY_TRSV2_RXCDR);
exynos_pcie_phy_writel(ep->phy_base, 0x82, PCIE_PHY_TRSV3_RXCDR);
/* change TX Pre-emphasis Level Control for lanes */
exynos_pcie_phy_writel(ep->phy_base, 0x39, PCIE_PHY_TRSV0_EMP_LVL);
exynos_pcie_phy_writel(ep->phy_base, 0x39, PCIE_PHY_TRSV1_EMP_LVL);
exynos_pcie_phy_writel(ep->phy_base, 0x39, PCIE_PHY_TRSV2_EMP_LVL);
exynos_pcie_phy_writel(ep->phy_base, 0x39, PCIE_PHY_TRSV3_EMP_LVL);
/* set LVCC */
exynos_pcie_phy_writel(ep->phy_base, 0x20, PCIE_PHY_TRSV0_LVCC);
exynos_pcie_phy_writel(ep->phy_base, 0xa0, PCIE_PHY_TRSV1_LVCC);
exynos_pcie_phy_writel(ep->phy_base, 0xa0, PCIE_PHY_TRSV2_LVCC);
exynos_pcie_phy_writel(ep->phy_base, 0xa0, PCIE_PHY_TRSV3_LVCC);
/* pulse for common reset */
exynos_pcie_phy_writel(ep->blk_base, 1, PCIE_PHY_COMMON_RESET);
udelay(500);
exynos_pcie_phy_writel(ep->blk_base, 0, PCIE_PHY_COMMON_RESET);
return 0;
}
static int exynos5440_pcie_phy_power_on(struct phy *phy)
{
struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
u32 val;
exynos_pcie_phy_writel(ep->blk_base, 0, PCIE_PHY_COMMON_RESET);
exynos_pcie_phy_writel(ep->blk_base, 0, PCIE_PHY_CMN_REG);
exynos_pcie_phy_writel(ep->blk_base, 0, PCIE_PHY_TRSVREG_RESET);
exynos_pcie_phy_writel(ep->blk_base, 0, PCIE_PHY_TRSV_RESET);
val = exynos_pcie_phy_readl(ep->phy_base, PCIE_PHY_COMMON_POWER);
val &= ~PCIE_PHY_COMMON_PD_CMN;
exynos_pcie_phy_writel(ep->phy_base, val, PCIE_PHY_COMMON_POWER);
val = exynos_pcie_phy_readl(ep->phy_base, PCIE_PHY_TRSV0_POWER);
val &= ~PCIE_PHY_TRSV0_PD_TSV;
exynos_pcie_phy_writel(ep->phy_base, val, PCIE_PHY_TRSV0_POWER);
val = exynos_pcie_phy_readl(ep->phy_base, PCIE_PHY_TRSV1_POWER);
val &= ~PCIE_PHY_TRSV1_PD_TSV;
exynos_pcie_phy_writel(ep->phy_base, val, PCIE_PHY_TRSV1_POWER);
val = exynos_pcie_phy_readl(ep->phy_base, PCIE_PHY_TRSV2_POWER);
val &= ~PCIE_PHY_TRSV2_PD_TSV;
exynos_pcie_phy_writel(ep->phy_base, val, PCIE_PHY_TRSV2_POWER);
val = exynos_pcie_phy_readl(ep->phy_base, PCIE_PHY_TRSV3_POWER);
val &= ~PCIE_PHY_TRSV3_PD_TSV;
exynos_pcie_phy_writel(ep->phy_base, val, PCIE_PHY_TRSV3_POWER);
return 0;
}
static int exynos5440_pcie_phy_power_off(struct phy *phy)
{
struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
u32 val;
if (readl_poll_timeout(ep->phy_base + PCIE_PHY_PLL_LOCKED, val,
(val != 0), 1, 500)) {
dev_err(&phy->dev, "PLL Locked: 0x%x\n", val);
return -ETIMEDOUT;
}
val = exynos_pcie_phy_readl(ep->phy_base, PCIE_PHY_COMMON_POWER);
val |= PCIE_PHY_COMMON_PD_CMN;
exynos_pcie_phy_writel(ep->phy_base, val, PCIE_PHY_COMMON_POWER);
val = exynos_pcie_phy_readl(ep->phy_base, PCIE_PHY_TRSV0_POWER);
val |= PCIE_PHY_TRSV0_PD_TSV;
exynos_pcie_phy_writel(ep->phy_base, val, PCIE_PHY_TRSV0_POWER);
val = exynos_pcie_phy_readl(ep->phy_base, PCIE_PHY_TRSV1_POWER);
val |= PCIE_PHY_TRSV1_PD_TSV;
exynos_pcie_phy_writel(ep->phy_base, val, PCIE_PHY_TRSV1_POWER);
val = exynos_pcie_phy_readl(ep->phy_base, PCIE_PHY_TRSV2_POWER);
val |= PCIE_PHY_TRSV2_PD_TSV;
exynos_pcie_phy_writel(ep->phy_base, val, PCIE_PHY_TRSV2_POWER);
val = exynos_pcie_phy_readl(ep->phy_base, PCIE_PHY_TRSV3_POWER);
val |= PCIE_PHY_TRSV3_PD_TSV;
exynos_pcie_phy_writel(ep->phy_base, val, PCIE_PHY_TRSV3_POWER);
return 0;
}
static int exynos5440_pcie_phy_reset(struct phy *phy)
{
struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
exynos_pcie_phy_writel(ep->blk_base, 0, PCIE_PHY_MAC_RESET);
exynos_pcie_phy_writel(ep->blk_base, 1, PCIE_PHY_GLOBAL_RESET);
exynos_pcie_phy_writel(ep->blk_base, 0, PCIE_PHY_GLOBAL_RESET);
return 0;
}
static const struct phy_ops exynos5440_phy_ops = {
.init = exynos5440_pcie_phy_init,
.power_on = exynos5440_pcie_phy_power_on,
.power_off = exynos5440_pcie_phy_power_off,
.reset = exynos5440_pcie_phy_reset,
.owner = THIS_MODULE,
};
static const struct exynos_pcie_phy_data exynos5440_pcie_phy_data = {
.ops = &exynos5440_phy_ops,
};
static const struct of_device_id exynos_pcie_phy_match[] = {
{
.compatible = "samsung,exynos5440-pcie-phy",
.data = &exynos5440_pcie_phy_data,
},
{},
};
static int exynos_pcie_phy_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct exynos_pcie_phy *exynos_phy;
struct phy *generic_phy;
struct phy_provider *phy_provider;
struct resource *res;
const struct exynos_pcie_phy_data *drv_data;
drv_data = of_device_get_match_data(dev);
if (!drv_data)
return -ENODEV;
exynos_phy = devm_kzalloc(dev, sizeof(*exynos_phy), GFP_KERNEL);
if (!exynos_phy)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
exynos_phy->phy_base = devm_ioremap_resource(dev, res);
if (IS_ERR(exynos_phy->phy_base))
return PTR_ERR(exynos_phy->phy_base);
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
exynos_phy->blk_base = devm_ioremap_resource(dev, res);
if (IS_ERR(exynos_phy->blk_base))
return PTR_ERR(exynos_phy->blk_base);
exynos_phy->drv_data = drv_data;
generic_phy = devm_phy_create(dev, dev->of_node, drv_data->ops);
if (IS_ERR(generic_phy)) {
dev_err(dev, "failed to create PHY\n");
return PTR_ERR(generic_phy);
}
phy_set_drvdata(generic_phy, exynos_phy);
phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
return PTR_ERR_OR_ZERO(phy_provider);
}
static struct platform_driver exynos_pcie_phy_driver = {
.probe = exynos_pcie_phy_probe,
.driver = {
.of_match_table = exynos_pcie_phy_match,
.name = "exynos_pcie_phy",
}
};
builtin_platform_driver(exynos_pcie_phy_driver);