ram: rk3399: Update lpddr4 vref_mode_ac

Update vref_mode_ac for lpddr4 based on VDDQ/3/2=16.8%

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Signed-off-by: YouMin Chen <cym@rock-chips.com>
Reviewed-by: Kever Yang <Kever.yang@rock-chips.com>

diff --git a/drivers/ram/rockchip/sdram_rk3399.c b/drivers/ram/rockchip/sdram_rk3399.c
index 84a09fe..da94bbe 100644 (file)
--- a/drivers/ram/rockchip/sdram_rk3399.c
+++ b/drivers/ram/rockchip/sdram_rk3399.c
@@ -366,7 +366,8 @@ static int phy_io_config(const struct chan_info *chan,
                        vref_value_dq = (rd_vref - 15300) / 521;
                }
                vref_mode_ac = 0x6;
-               vref_value_ac = 0x1f;
+               /* VDDQ/3/2=16.8% */
+               vref_value_ac = 0x3;
        } else if (params->base.dramtype == LPDDR3) {
                if (params->base.odt == 1) {
                        vref_mode_dq = 0x5;  /* LPDDR3 ODT */