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phy: rockchip-emmc: configure frequency range and drive impedance

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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>
This commit is contained in:
Shawn Lin 2016-06-20 10:56:41 -07:00 committed by Ulf Hansson
parent 4d54a25ba5
commit d74857720d
1 changed files with 27 additions and 0 deletions
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27
drivers/phy/phy-rockchip-emmc.c
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@ -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)