diff options
Diffstat (limited to 'drivers/phy/rockchip/phy-rockchip-emmc.c')
| -rw-r--r-- | drivers/phy/rockchip/phy-rockchip-emmc.c | 80 |
1 files changed, 64 insertions, 16 deletions
diff --git a/drivers/phy/rockchip/phy-rockchip-emmc.c b/drivers/phy/rockchip/phy-rockchip-emmc.c index 19bf84f0bc67..5187983c58e5 100644 --- a/drivers/phy/rockchip/phy-rockchip-emmc.c +++ b/drivers/phy/rockchip/phy-rockchip-emmc.c @@ -1,21 +1,14 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Rockchip emmc PHY driver * * Copyright (C) 2016 Shawn Lin <shawn.lin@rock-chips.com> * Copyright (C) 2016 ROCKCHIP, Inc. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. */ #include <linux/clk.h> #include <linux/delay.h> +#include <linux/hw_bitfield.h> #include <linux/mfd/syscon.h> #include <linux/module.h> #include <linux/of.h> @@ -29,7 +22,7 @@ * only if BIT(x + 16) set to 1 the BIT(x) can be written. */ #define HIWORD_UPDATE(val, mask, shift) \ - ((val) << (shift) | (mask) << ((shift) + 16)) + (FIELD_PREP_WM16((mask) << (shift), (val))) /* Register definition */ #define GRF_EMMCPHY_CON0 0x0 @@ -73,8 +66,14 @@ #define PHYCTRL_OTAPDLYENA 0x1 #define PHYCTRL_OTAPDLYENA_MASK 0x1 #define PHYCTRL_OTAPDLYENA_SHIFT 0xb +#define PHYCTRL_OTAPDLYSEL_DEFAULT 0x4 +#define PHYCTRL_OTAPDLYSEL_MAXVALUE 0xf #define PHYCTRL_OTAPDLYSEL_MASK 0xf #define PHYCTRL_OTAPDLYSEL_SHIFT 0x7 +#define PHYCTRL_REN_STRB_DISABLE 0x0 +#define PHYCTRL_REN_STRB_ENABLE 0x1 +#define PHYCTRL_REN_STRB_MASK 0x1 +#define PHYCTRL_REN_STRB_SHIFT 0x9 #define PHYCTRL_IS_CALDONE(x) \ ((((x) >> PHYCTRL_CALDONE_SHIFT) & \ @@ -87,6 +86,9 @@ struct rockchip_emmc_phy { unsigned int reg_offset; struct regmap *reg_base; struct clk *emmcclk; + unsigned int drive_impedance; + unsigned int enable_strobe_pulldown; + unsigned int output_tapdelay_select; }; static int rockchip_emmc_phy_power(struct phy *phy, bool on_off) @@ -247,15 +249,17 @@ static int rockchip_emmc_phy_init(struct phy *phy) * - SDHCI driver to get the PHY * - SDHCI driver to init the PHY * - * The clock is optional, so upon any error we just set to NULL. + * The clock is optional, using clk_get_optional() to get the clock + * and do error processing if the return value != NULL * * NOTE: we don't do anything special for EPROBE_DEFER here. Given the * above expected use case, EPROBE_DEFER isn't sensible to expect, so * it's just like any other error. */ - rk_phy->emmcclk = clk_get(&phy->dev, "emmcclk"); + rk_phy->emmcclk = clk_get_optional(&phy->dev, "emmcclk"); if (IS_ERR(rk_phy->emmcclk)) { - dev_dbg(&phy->dev, "Error getting emmcclk: %d\n", ret); + ret = PTR_ERR(rk_phy->emmcclk); + dev_err(&phy->dev, "Error getting emmcclk: %d\n", ret); rk_phy->emmcclk = NULL; } @@ -281,10 +285,10 @@ static int rockchip_emmc_phy_power_on(struct phy *phy) { struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy); - /* Drive impedance: 50 Ohm */ + /* Drive impedance: from DTS */ regmap_write(rk_phy->reg_base, rk_phy->reg_offset + GRF_EMMCPHY_CON6, - HIWORD_UPDATE(PHYCTRL_DR_50OHM, + HIWORD_UPDATE(rk_phy->drive_impedance, PHYCTRL_DR_MASK, PHYCTRL_DR_SHIFT)); @@ -298,10 +302,17 @@ static int rockchip_emmc_phy_power_on(struct phy *phy) /* Output tap delay */ regmap_write(rk_phy->reg_base, rk_phy->reg_offset + GRF_EMMCPHY_CON0, - HIWORD_UPDATE(4, + HIWORD_UPDATE(rk_phy->output_tapdelay_select, PHYCTRL_OTAPDLYSEL_MASK, PHYCTRL_OTAPDLYSEL_SHIFT)); + /* Internal pull-down for strobe line */ + regmap_write(rk_phy->reg_base, + rk_phy->reg_offset + GRF_EMMCPHY_CON2, + HIWORD_UPDATE(rk_phy->enable_strobe_pulldown, + PHYCTRL_REN_STRB_MASK, + PHYCTRL_REN_STRB_SHIFT)); + /* Power up emmc phy analog blocks */ return rockchip_emmc_phy_power(phy, PHYCTRL_PDB_PWR_ON); } @@ -314,6 +325,26 @@ static const struct phy_ops ops = { .owner = THIS_MODULE, }; +static u32 convert_drive_impedance_ohm(struct platform_device *pdev, u32 dr_ohm) +{ + switch (dr_ohm) { + case 100: + return PHYCTRL_DR_100OHM; + case 66: + return PHYCTRL_DR_66OHM; + case 50: + return PHYCTRL_DR_50OHM; + case 40: + return PHYCTRL_DR_40OHM; + case 33: + return PHYCTRL_DR_33OHM; + } + + dev_warn(&pdev->dev, "Invalid value %u for drive-impedance-ohm.\n", + dr_ohm); + return PHYCTRL_DR_50OHM; +} + static int rockchip_emmc_phy_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -322,6 +353,7 @@ static int rockchip_emmc_phy_probe(struct platform_device *pdev) struct phy_provider *phy_provider; struct regmap *grf; unsigned int reg_offset; + u32 val; if (!dev->parent || !dev->parent->of_node) return -ENODEV; @@ -344,6 +376,22 @@ static int rockchip_emmc_phy_probe(struct platform_device *pdev) rk_phy->reg_offset = reg_offset; rk_phy->reg_base = grf; + rk_phy->drive_impedance = PHYCTRL_DR_50OHM; + rk_phy->enable_strobe_pulldown = PHYCTRL_REN_STRB_DISABLE; + rk_phy->output_tapdelay_select = PHYCTRL_OTAPDLYSEL_DEFAULT; + + if (!of_property_read_u32(dev->of_node, "drive-impedance-ohm", &val)) + rk_phy->drive_impedance = convert_drive_impedance_ohm(pdev, val); + + if (of_property_read_bool(dev->of_node, "rockchip,enable-strobe-pulldown")) + rk_phy->enable_strobe_pulldown = PHYCTRL_REN_STRB_ENABLE; + + if (!of_property_read_u32(dev->of_node, "rockchip,output-tapdelay-select", &val)) { + if (val <= PHYCTRL_OTAPDLYSEL_MAXVALUE) + rk_phy->output_tapdelay_select = val; + else + dev_err(dev, "output-tapdelay-select exceeds limit, apply default\n"); + } generic_phy = devm_phy_create(dev, dev->of_node, &ops); if (IS_ERR(generic_phy)) { |