diff options
Diffstat (limited to 'drivers/phy/tegra/phy-tegra194-p2u.c')
-rw-r--r-- | drivers/phy/tegra/phy-tegra194-p2u.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/drivers/phy/tegra/phy-tegra194-p2u.c b/drivers/phy/tegra/phy-tegra194-p2u.c new file mode 100644 index 0000000000..f49b417c9e --- /dev/null +++ b/drivers/phy/tegra/phy-tegra194-p2u.c @@ -0,0 +1,178 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * P2U (PIPE to UPHY) driver for Tegra T194 SoC + * + * Copyright (C) 2019-2022 NVIDIA Corporation. + * + * Author: Vidya Sagar <vidyas@nvidia.com> + */ + +#include <linux/err.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/phy/phy.h> +#include <linux/platform_device.h> + +#define P2U_CONTROL_CMN 0x74 +#define P2U_CONTROL_CMN_ENABLE_L2_EXIT_RATE_CHANGE BIT(13) +#define P2U_CONTROL_CMN_SKP_SIZE_PROTECTION_EN BIT(20) + +#define P2U_PERIODIC_EQ_CTRL_GEN3 0xc0 +#define P2U_PERIODIC_EQ_CTRL_GEN3_PERIODIC_EQ_EN BIT(0) +#define P2U_PERIODIC_EQ_CTRL_GEN3_INIT_PRESET_EQ_TRAIN_EN BIT(1) +#define P2U_PERIODIC_EQ_CTRL_GEN4 0xc4 +#define P2U_PERIODIC_EQ_CTRL_GEN4_INIT_PRESET_EQ_TRAIN_EN BIT(1) + +#define P2U_RX_DEBOUNCE_TIME 0xa4 +#define P2U_RX_DEBOUNCE_TIME_DEBOUNCE_TIMER_MASK 0xffff +#define P2U_RX_DEBOUNCE_TIME_DEBOUNCE_TIMER_VAL 160 + +#define P2U_DIR_SEARCH_CTRL 0xd4 +#define P2U_DIR_SEARCH_CTRL_GEN4_FINE_GRAIN_SEARCH_TWICE BIT(18) + +struct tegra_p2u_of_data { + bool one_dir_search; +}; + +struct tegra_p2u { + void __iomem *base; + bool skip_sz_protection_en; /* Needed to support two retimers */ + struct tegra_p2u_of_data *of_data; +}; + +static inline void p2u_writel(struct tegra_p2u *phy, const u32 value, + const u32 reg) +{ + writel_relaxed(value, phy->base + reg); +} + +static inline u32 p2u_readl(struct tegra_p2u *phy, const u32 reg) +{ + return readl_relaxed(phy->base + reg); +} + +static int tegra_p2u_power_on(struct phy *x) +{ + struct tegra_p2u *phy = phy_get_drvdata(x); + u32 val; + + if (phy->skip_sz_protection_en) { + val = p2u_readl(phy, P2U_CONTROL_CMN); + val |= P2U_CONTROL_CMN_SKP_SIZE_PROTECTION_EN; + p2u_writel(phy, val, P2U_CONTROL_CMN); + } + + val = p2u_readl(phy, P2U_PERIODIC_EQ_CTRL_GEN3); + val &= ~P2U_PERIODIC_EQ_CTRL_GEN3_PERIODIC_EQ_EN; + val |= P2U_PERIODIC_EQ_CTRL_GEN3_INIT_PRESET_EQ_TRAIN_EN; + p2u_writel(phy, val, P2U_PERIODIC_EQ_CTRL_GEN3); + + val = p2u_readl(phy, P2U_PERIODIC_EQ_CTRL_GEN4); + val |= P2U_PERIODIC_EQ_CTRL_GEN4_INIT_PRESET_EQ_TRAIN_EN; + p2u_writel(phy, val, P2U_PERIODIC_EQ_CTRL_GEN4); + + val = p2u_readl(phy, P2U_RX_DEBOUNCE_TIME); + val &= ~P2U_RX_DEBOUNCE_TIME_DEBOUNCE_TIMER_MASK; + val |= P2U_RX_DEBOUNCE_TIME_DEBOUNCE_TIMER_VAL; + p2u_writel(phy, val, P2U_RX_DEBOUNCE_TIME); + + if (phy->of_data->one_dir_search) { + val = p2u_readl(phy, P2U_DIR_SEARCH_CTRL); + val &= ~P2U_DIR_SEARCH_CTRL_GEN4_FINE_GRAIN_SEARCH_TWICE; + p2u_writel(phy, val, P2U_DIR_SEARCH_CTRL); + } + + return 0; +} + +static int tegra_p2u_calibrate(struct phy *x) +{ + struct tegra_p2u *phy = phy_get_drvdata(x); + u32 val; + + val = p2u_readl(phy, P2U_CONTROL_CMN); + val |= P2U_CONTROL_CMN_ENABLE_L2_EXIT_RATE_CHANGE; + p2u_writel(phy, val, P2U_CONTROL_CMN); + + return 0; +} + +static const struct phy_ops ops = { + .power_on = tegra_p2u_power_on, + .calibrate = tegra_p2u_calibrate, + .owner = THIS_MODULE, +}; + +static int tegra_p2u_probe(struct platform_device *pdev) +{ + struct phy_provider *phy_provider; + struct device *dev = &pdev->dev; + struct phy *generic_phy; + struct tegra_p2u *phy; + + phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL); + if (!phy) + return -ENOMEM; + + phy->of_data = + (struct tegra_p2u_of_data *)of_device_get_match_data(dev); + if (!phy->of_data) + return -EINVAL; + + phy->base = devm_platform_ioremap_resource_byname(pdev, "ctl"); + if (IS_ERR(phy->base)) + return PTR_ERR(phy->base); + + phy->skip_sz_protection_en = + of_property_read_bool(dev->of_node, + "nvidia,skip-sz-protect-en"); + + platform_set_drvdata(pdev, phy); + + generic_phy = devm_phy_create(dev, NULL, &ops); + if (IS_ERR(generic_phy)) + return PTR_ERR(generic_phy); + + phy_set_drvdata(generic_phy, phy); + + phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); + if (IS_ERR(phy_provider)) + return PTR_ERR(phy_provider); + + return 0; +} + +static const struct tegra_p2u_of_data tegra194_p2u_of_data = { + .one_dir_search = false, +}; + +static const struct tegra_p2u_of_data tegra234_p2u_of_data = { + .one_dir_search = true, +}; + +static const struct of_device_id tegra_p2u_id_table[] = { + { + .compatible = "nvidia,tegra194-p2u", + .data = &tegra194_p2u_of_data, + }, + { + .compatible = "nvidia,tegra234-p2u", + .data = &tegra234_p2u_of_data, + }, + {} +}; +MODULE_DEVICE_TABLE(of, tegra_p2u_id_table); + +static struct platform_driver tegra_p2u_driver = { + .probe = tegra_p2u_probe, + .driver = { + .name = "tegra194-p2u", + .of_match_table = tegra_p2u_id_table, + }, +}; +module_platform_driver(tegra_p2u_driver); + +MODULE_AUTHOR("Vidya Sagar <vidyas@nvidia.com>"); +MODULE_DESCRIPTION("NVIDIA Tegra194 PIPE2UPHY PHY driver"); +MODULE_LICENSE("GPL v2"); |