From 9dc00ef625cfd3a9fe130ab8e75473fad6d048dc Mon Sep 17 00:00:00 2001 From: Lin Huang Date: Thu, 7 Jul 2016 19:19:48 +0800 Subject: 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 Original-Commit-Id: fbc1c13f9ab808fc907b2e3f9bde1d09f92980f1 Original-Change-Id: I231f5b1bd45ff262686fbacbaf119a8a57fad27b Original-Signed-off-by: Lin Huang Original-Reviewed-on: https://chromium-review.googlesource.com/358761 Original-Commit-Ready: Dan Shi Original-Tested-by: Caesar Wang Original-Reviewed-by: Julius Werner Reviewed-on: https://review.coreboot.org/15811 Tested-by: build bot (Jenkins) Reviewed-by: Furquan Shaikh --- src/soc/rockchip/rk3399/sdram.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'src') diff --git a/src/soc/rockchip/rk3399/sdram.c b/src/soc/rockchip/rk3399/sdram.c index 293a0f2108..c3db47bcf6 100644 --- a/src/soc/rockchip/rk3399/sdram.c +++ b/src/soc/rockchip/rk3399/sdram.c @@ -182,32 +182,39 @@ static void set_ds_odt(u32 channel, 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 @@ static void set_ds_odt(u32 channel, 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); -- cgit v1.2.3