kernel_optimize_test/drivers/phy/samsung/phy-exynos5250-sata.c
Marek Szyprowski 6aeec986f1 phy: samsung: disable bind/unbind platform driver feature
Samsung PHY drivers control the power to the SoC core components needed by
their client devices (USB HCDs, SATA, camera ISP bridge, DP encoder) to
properly operate. Disabling PHYs in runtime usually causes the client
device to crash with external abort exception or similar issue due to lack
of API to notify clients about PHY removal. This patch removes the
possiblity to unbind Samsung Exynos PHY drivers in runtime.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2019-08-23 09:40:59 +05:30

249 lines
6.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Samsung SATA SerDes(PHY) driver
*
* Copyright (C) 2013 Samsung Electronics Co., Ltd.
* Authors: Girish K S <ks.giri@samsung.com>
* Yuvaraj Kumar C D <yuvaraj.cd@samsung.com>
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/spinlock.h>
#include <linux/mfd/syscon.h>
#define SATAPHY_CONTROL_OFFSET 0x0724
#define EXYNOS5_SATAPHY_PMU_ENABLE BIT(0)
#define EXYNOS5_SATA_RESET 0x4
#define RESET_GLOBAL_RST_N BIT(0)
#define RESET_CMN_RST_N BIT(1)
#define RESET_CMN_BLOCK_RST_N BIT(2)
#define RESET_CMN_I2C_RST_N BIT(3)
#define RESET_TX_RX_PIPE_RST_N BIT(4)
#define RESET_TX_RX_BLOCK_RST_N BIT(5)
#define RESET_TX_RX_I2C_RST_N (BIT(6) | BIT(7))
#define LINK_RESET 0xf0000
#define EXYNOS5_SATA_MODE0 0x10
#define SATA_SPD_GEN3 BIT(1)
#define EXYNOS5_SATA_CTRL0 0x14
#define CTRL0_P0_PHY_CALIBRATED_SEL BIT(9)
#define CTRL0_P0_PHY_CALIBRATED BIT(8)
#define EXYNOS5_SATA_PHSATA_CTRLM 0xe0
#define PHCTRLM_REF_RATE BIT(1)
#define PHCTRLM_HIGH_SPEED BIT(0)
#define EXYNOS5_SATA_PHSATA_STATM 0xf0
#define PHSTATM_PLL_LOCKED BIT(0)
#define PHY_PLL_TIMEOUT (usecs_to_jiffies(1000))
struct exynos_sata_phy {
struct phy *phy;
struct clk *phyclk;
void __iomem *regs;
struct regmap *pmureg;
struct i2c_client *client;
};
static int wait_for_reg_status(void __iomem *base, u32 reg, u32 checkbit,
u32 status)
{
unsigned long timeout = jiffies + PHY_PLL_TIMEOUT;
while (time_before(jiffies, timeout)) {
if ((readl(base + reg) & checkbit) == status)
return 0;
}
return -EFAULT;
}
static int exynos_sata_phy_power_on(struct phy *phy)
{
struct exynos_sata_phy *sata_phy = phy_get_drvdata(phy);
return regmap_update_bits(sata_phy->pmureg, SATAPHY_CONTROL_OFFSET,
EXYNOS5_SATAPHY_PMU_ENABLE, true);
}
static int exynos_sata_phy_power_off(struct phy *phy)
{
struct exynos_sata_phy *sata_phy = phy_get_drvdata(phy);
return regmap_update_bits(sata_phy->pmureg, SATAPHY_CONTROL_OFFSET,
EXYNOS5_SATAPHY_PMU_ENABLE, false);
}
static int exynos_sata_phy_init(struct phy *phy)
{
u32 val = 0;
int ret = 0;
u8 buf[] = { 0x3a, 0x0b };
struct exynos_sata_phy *sata_phy = phy_get_drvdata(phy);
ret = regmap_update_bits(sata_phy->pmureg, SATAPHY_CONTROL_OFFSET,
EXYNOS5_SATAPHY_PMU_ENABLE, true);
if (ret != 0)
dev_err(&sata_phy->phy->dev, "phy init failed\n");
writel(val, sata_phy->regs + EXYNOS5_SATA_RESET);
val = readl(sata_phy->regs + EXYNOS5_SATA_RESET);
val |= RESET_GLOBAL_RST_N | RESET_CMN_RST_N | RESET_CMN_BLOCK_RST_N
| RESET_CMN_I2C_RST_N | RESET_TX_RX_PIPE_RST_N
| RESET_TX_RX_BLOCK_RST_N | RESET_TX_RX_I2C_RST_N;
writel(val, sata_phy->regs + EXYNOS5_SATA_RESET);
val = readl(sata_phy->regs + EXYNOS5_SATA_RESET);
val |= LINK_RESET;
writel(val, sata_phy->regs + EXYNOS5_SATA_RESET);
val = readl(sata_phy->regs + EXYNOS5_SATA_RESET);
val |= RESET_CMN_RST_N;
writel(val, sata_phy->regs + EXYNOS5_SATA_RESET);
val = readl(sata_phy->regs + EXYNOS5_SATA_PHSATA_CTRLM);
val &= ~PHCTRLM_REF_RATE;
writel(val, sata_phy->regs + EXYNOS5_SATA_PHSATA_CTRLM);
/* High speed enable for Gen3 */
val = readl(sata_phy->regs + EXYNOS5_SATA_PHSATA_CTRLM);
val |= PHCTRLM_HIGH_SPEED;
writel(val, sata_phy->regs + EXYNOS5_SATA_PHSATA_CTRLM);
val = readl(sata_phy->regs + EXYNOS5_SATA_CTRL0);
val |= CTRL0_P0_PHY_CALIBRATED_SEL | CTRL0_P0_PHY_CALIBRATED;
writel(val, sata_phy->regs + EXYNOS5_SATA_CTRL0);
val = readl(sata_phy->regs + EXYNOS5_SATA_MODE0);
val |= SATA_SPD_GEN3;
writel(val, sata_phy->regs + EXYNOS5_SATA_MODE0);
ret = i2c_master_send(sata_phy->client, buf, sizeof(buf));
if (ret < 0)
return ret;
/* release cmu reset */
val = readl(sata_phy->regs + EXYNOS5_SATA_RESET);
val &= ~RESET_CMN_RST_N;
writel(val, sata_phy->regs + EXYNOS5_SATA_RESET);
val = readl(sata_phy->regs + EXYNOS5_SATA_RESET);
val |= RESET_CMN_RST_N;
writel(val, sata_phy->regs + EXYNOS5_SATA_RESET);
ret = wait_for_reg_status(sata_phy->regs,
EXYNOS5_SATA_PHSATA_STATM,
PHSTATM_PLL_LOCKED, 1);
if (ret < 0)
dev_err(&sata_phy->phy->dev,
"PHY PLL locking failed\n");
return ret;
}
static const struct phy_ops exynos_sata_phy_ops = {
.init = exynos_sata_phy_init,
.power_on = exynos_sata_phy_power_on,
.power_off = exynos_sata_phy_power_off,
.owner = THIS_MODULE,
};
static int exynos_sata_phy_probe(struct platform_device *pdev)
{
struct exynos_sata_phy *sata_phy;
struct device *dev = &pdev->dev;
struct resource *res;
struct phy_provider *phy_provider;
struct device_node *node;
int ret = 0;
sata_phy = devm_kzalloc(dev, sizeof(*sata_phy), GFP_KERNEL);
if (!sata_phy)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
sata_phy->regs = devm_ioremap_resource(dev, res);
if (IS_ERR(sata_phy->regs))
return PTR_ERR(sata_phy->regs);
sata_phy->pmureg = syscon_regmap_lookup_by_phandle(dev->of_node,
"samsung,syscon-phandle");
if (IS_ERR(sata_phy->pmureg)) {
dev_err(dev, "syscon regmap lookup failed.\n");
return PTR_ERR(sata_phy->pmureg);
}
node = of_parse_phandle(dev->of_node,
"samsung,exynos-sataphy-i2c-phandle", 0);
if (!node)
return -EINVAL;
sata_phy->client = of_find_i2c_device_by_node(node);
if (!sata_phy->client)
return -EPROBE_DEFER;
dev_set_drvdata(dev, sata_phy);
sata_phy->phyclk = devm_clk_get(dev, "sata_phyctrl");
if (IS_ERR(sata_phy->phyclk)) {
dev_err(dev, "failed to get clk for PHY\n");
return PTR_ERR(sata_phy->phyclk);
}
ret = clk_prepare_enable(sata_phy->phyclk);
if (ret < 0) {
dev_err(dev, "failed to enable source clk\n");
return ret;
}
sata_phy->phy = devm_phy_create(dev, NULL, &exynos_sata_phy_ops);
if (IS_ERR(sata_phy->phy)) {
clk_disable_unprepare(sata_phy->phyclk);
dev_err(dev, "failed to create PHY\n");
return PTR_ERR(sata_phy->phy);
}
phy_set_drvdata(sata_phy->phy, sata_phy);
phy_provider = devm_of_phy_provider_register(dev,
of_phy_simple_xlate);
if (IS_ERR(phy_provider)) {
clk_disable_unprepare(sata_phy->phyclk);
return PTR_ERR(phy_provider);
}
return 0;
}
static const struct of_device_id exynos_sata_phy_of_match[] = {
{ .compatible = "samsung,exynos5250-sata-phy" },
{ },
};
MODULE_DEVICE_TABLE(of, exynos_sata_phy_of_match);
static struct platform_driver exynos_sata_phy_driver = {
.probe = exynos_sata_phy_probe,
.driver = {
.of_match_table = exynos_sata_phy_of_match,
.name = "samsung,sata-phy",
.suppress_bind_attrs = true,
}
};
module_platform_driver(exynos_sata_phy_driver);
MODULE_DESCRIPTION("Samsung SerDes PHY driver");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Girish K S <ks.giri@samsung.com>");
MODULE_AUTHOR("Yuvaraj C D <yuvaraj.cd@samsung.com>");