rockchip/rk3399: set CA drive strength to 48ohms
As shown in testing, if CA use 34.3ohms drive strength, it leads
to an overshoot. To fix this, change the drive strength to 48 ohms.
BRANCH=none
BUG=chrome-os-partner:54871
TEST=run "stressapptest -M 1024 -s 1000" on kevin board and pass
Change-Id: I8666474fc18391da14a3338611f962f2f08f36d0
Signed-off-by: Martin Roth <martinroth@chromium.org>
Original-Commit-Id: fbc1c13f9ab808fc907b2e3f9bde1d09f92980f1
Original-Change-Id: I231f5b1bd45ff262686fbacbaf119a8a57fad27b
Original-Signed-off-by: Lin Huang <hl@rock-chips.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/358761
Original-Commit-Ready: Dan Shi <dshi@chromium.org>
Original-Tested-by: Caesar Wang <wxt@rock-chips.com>
Original-Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/15811
Tested-by: build bot (Jenkins)
Reviewed-by: Furquan Shaikh <furquan@google.com>
diff --git a/src/soc/rockchip/rk3399/sdram.c b/src/soc/rockchip/rk3399/sdram.c
index 293a0f2..c3db47b 100644
--- a/src/soc/rockchip/rk3399/sdram.c
+++ b/src/soc/rockchip/rk3399/sdram.c
@@ -182,32 +182,39 @@
u32 tsel_idle_en, tsel_wr_en, tsel_rd_en;
u32 tsel_idle_select_p, tsel_wr_select_p, tsel_rd_select_p;
+ u32 ca_tsel_wr_select_p, ca_tsel_wr_select_n;
u32 tsel_idle_select_n, tsel_wr_select_n, tsel_rd_select_n;
u32 reg_value;
if (sdram_params->dramtype == LPDDR4) {
tsel_rd_select_p = PHY_DRV_ODT_Hi_Z;
tsel_wr_select_p = PHY_DRV_ODT_40;
+ ca_tsel_wr_select_p = PHY_DRV_ODT_40;
tsel_idle_select_p = PHY_DRV_ODT_Hi_Z;
tsel_rd_select_n = PHY_DRV_ODT_240;
tsel_wr_select_n = PHY_DRV_ODT_40;
+ ca_tsel_wr_select_n = PHY_DRV_ODT_40;
tsel_idle_select_n = PHY_DRV_ODT_240;
} else if (sdram_params->dramtype == LPDDR3) {
tsel_rd_select_p = PHY_DRV_ODT_240;
tsel_wr_select_p = PHY_DRV_ODT_34_3;
+ ca_tsel_wr_select_p = PHY_DRV_ODT_48;
tsel_idle_select_p = PHY_DRV_ODT_240;
tsel_rd_select_n = PHY_DRV_ODT_Hi_Z;
tsel_wr_select_n = PHY_DRV_ODT_34_3;
+ ca_tsel_wr_select_n = PHY_DRV_ODT_48;
tsel_idle_select_n = PHY_DRV_ODT_Hi_Z;
} else {
tsel_rd_select_p = PHY_DRV_ODT_240;
tsel_wr_select_p = PHY_DRV_ODT_34_3;
+ ca_tsel_wr_select_p = PHY_DRV_ODT_34_3;
tsel_idle_select_p = PHY_DRV_ODT_240;
tsel_rd_select_n = PHY_DRV_ODT_240;
tsel_wr_select_n = PHY_DRV_ODT_34_3;
+ ca_tsel_wr_select_n = PHY_DRV_ODT_34_3;
tsel_idle_select_n = PHY_DRV_ODT_240;
}
@@ -243,7 +250,7 @@
clrsetbits_le32(&denali_phy[391], 0xffffff, reg_value);
/* phy_adr_tsel_select_ 8bits DENALI_PHY_544/672/800 offset_0 */
- reg_value = tsel_wr_select_n | (tsel_wr_select_p << 0x4);
+ reg_value = ca_tsel_wr_select_n | (ca_tsel_wr_select_p << 0x4);
clrsetbits_le32(&denali_phy[544], 0xff, reg_value);
clrsetbits_le32(&denali_phy[672], 0xff, reg_value);
clrsetbits_le32(&denali_phy[800], 0xff, reg_value);