diff options
| author | Chris Ruehl <chris.ruehl@gtsys.com.hk> | 2020-12-02 11:25:06 +0300 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2020-12-05 11:10:48 +0300 |
| commit | a8cef928276bbf8254d0067cda21dbe6210ea1aa (patch) | |
| tree | 451d7ac15b2f76c6946291c1b6d28dc32f9641ca /drivers/phy | |
| parent | 31de313dfdcf6971b0a1c30f86eabaa1eede74b3 (diff) | |
| download | linux-a8cef928276bbf8254d0067cda21dbe6210ea1aa.tar.xz | |
phy: rockchip-emmc: output tap delay dt property
Update the rockchip-emmc phy to set the otapdlysec register with
a dt property. This was mentioned from Brian Norris when he sent
the path to set the default value in the driver.
This patch add a dt property 'output-tapdelay-select' u32 and allow
to set the 0x0-0xf. If not set in dts, the old default 0x4 applies.
Tested with our customized rk3399 to tune the eMMC.
Signed-off-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>
Link: https://lore.kernel.org/r/20201202082507.3536-2-chris.ruehl@gtsys.com.hk
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/phy')
| -rw-r--r-- | drivers/phy/rockchip/phy-rockchip-emmc.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/phy/rockchip/phy-rockchip-emmc.c b/drivers/phy/rockchip/phy-rockchip-emmc.c index 48e2d75b1004..1e424f263e7a 100644 --- a/drivers/phy/rockchip/phy-rockchip-emmc.c +++ b/drivers/phy/rockchip/phy-rockchip-emmc.c @@ -65,6 +65,8 @@ #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 @@ -85,6 +87,7 @@ struct rockchip_emmc_phy { 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) @@ -296,7 +299,7 @@ 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)); @@ -372,6 +375,7 @@ static int rockchip_emmc_phy_probe(struct platform_device *pdev) 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); @@ -379,6 +383,13 @@ static int rockchip_emmc_phy_probe(struct platform_device *pdev) if (of_property_read_bool(dev->of_node, "enable-strobe-pulldown")) rk_phy->enable_strobe_pulldown = PHYCTRL_REN_STRB_ENABLE; + if (!of_property_read_u32(dev->of_node, "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)) { dev_err(dev, "failed to create PHY\n"); |