diff options
| author | Shawn Lin <shawn.lin@rock-chips.com> | 2016-06-20 10:56:41 -0700 |
|---|---|---|
| committer | Ulf Hansson <ulf.hansson@linaro.org> | 2016-07-25 10:34:15 +0200 |
| commit | d74857720d41c58f74966b5d06ebfa9111a62c69 (patch) | |
| tree | 186844d76bc1b66b682f111529b68c11585bcb64 /drivers/phy | |
| parent | 4d54a25ba5df8d4fd1c1604d1526c9279237ac27 (diff) | |
| download | linux-d74857720d41c58f74966b5d06ebfa9111a62c69.tar.bz2 | |
phy: rockchip-emmc: configure frequency range and drive impedance
Signal integrity analysis has suggested we set these values. Do this in
power_on(), so that they get reconfigured after suspend/resume.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Diffstat (limited to 'drivers/phy')
| -rw-r--r-- | drivers/phy/phy-rockchip-emmc.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/drivers/phy/phy-rockchip-emmc.c b/drivers/phy/phy-rockchip-emmc.c index 48cbe691a889..f2f75cf69af1 100644 --- a/drivers/phy/phy-rockchip-emmc.c +++ b/drivers/phy/phy-rockchip-emmc.c @@ -56,6 +56,19 @@ #define PHYCTRL_DLLRDY_SHIFT 0x5 #define PHYCTRL_DLLRDY_DONE 0x1 #define PHYCTRL_DLLRDY_GOING 0x0 +#define PHYCTRL_FREQSEL_200M 0x0 +#define PHYCTRL_FREQSEL_50M 0x1 +#define PHYCTRL_FREQSEL_100M 0x2 +#define PHYCTRL_FREQSEL_150M 0x3 +#define PHYCTRL_FREQSEL_MASK 0x3 +#define PHYCTRL_FREQSEL_SHIFT 0xc +#define PHYCTRL_DR_MASK 0x7 +#define PHYCTRL_DR_SHIFT 0x4 +#define PHYCTRL_DR_50OHM 0x0 +#define PHYCTRL_DR_33OHM 0x1 +#define PHYCTRL_DR_66OHM 0x2 +#define PHYCTRL_DR_100OHM 0x3 +#define PHYCTRL_DR_40OHM 0x4 struct rockchip_emmc_phy { unsigned int reg_offset; @@ -154,6 +167,20 @@ static int rockchip_emmc_phy_power_on(struct phy *phy) struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy); int ret = 0; + /* DLL operation: 200 MHz */ + regmap_write(rk_phy->reg_base, + rk_phy->reg_offset + GRF_EMMCPHY_CON0, + HIWORD_UPDATE(PHYCTRL_FREQSEL_200M, + PHYCTRL_FREQSEL_MASK, + PHYCTRL_FREQSEL_SHIFT)); + + /* Drive impedance: 50 Ohm */ + regmap_write(rk_phy->reg_base, + rk_phy->reg_offset + GRF_EMMCPHY_CON6, + HIWORD_UPDATE(PHYCTRL_DR_50OHM, + PHYCTRL_DR_MASK, + PHYCTRL_DR_SHIFT)); + /* Power up emmc phy analog blocks */ ret = rockchip_emmc_phy_power(rk_phy, PHYCTRL_PDB_PWR_ON); if (ret) |