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authorChris Ruehl <chris.ruehl@gtsys.com.hk>2020-12-02 11:25:06 +0300
committerVinod Koul <vkoul@kernel.org>2020-12-05 11:10:48 +0300
commita8cef928276bbf8254d0067cda21dbe6210ea1aa (patch)
tree451d7ac15b2f76c6946291c1b6d28dc32f9641ca /drivers/phy
parent31de313dfdcf6971b0a1c30f86eabaa1eede74b3 (diff)
downloadlinux-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.c13
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");