MLK-17055 imx8mq: evk: update DDR seting for display flickering issue

1. With this change, no flickering when LCDIF + MIPI-DSI
   in 720p60 single display case
2. With this change, no flickering when DCSS in 4kp60
   while running 4x memtester at the same time

side effect:
GPU resolve performance downgrade ~20%, no obvious impact
to non-resolve GPU cases.

Signed-off-by: Jian Li <jian.li@nxp.com>

diff --git a/board/freescale/imx8mq_evk/ddr/ddr_init.c b/board/freescale/imx8mq_evk/ddr/ddr_init.c
index 8572a6f..ba46201 100644 (file)
--- a/board/freescale/imx8mq_evk/ddr/ddr_init.c
+++ b/board/freescale/imx8mq_evk/ddr/ddr_init.c
@@ -90,7 +90,7 @@ void lpddr4_800MHz_cfg_umctl2(void)
        dwc_ddrphy_apb_wr(DDRC_SCHED(0), 0x29511505);
        dwc_ddrphy_apb_wr(DDRC_SCHED1(0), 0x0000002c);
        dwc_ddrphy_apb_wr(DDRC_PERFHPR1(0), 0x5900575b);
-       dwc_ddrphy_apb_wr(DDRC_PERFLPR1(0), 0x900093e7);
+       dwc_ddrphy_apb_wr(DDRC_PERFLPR1(0), 0x00000009);
        dwc_ddrphy_apb_wr(DDRC_PERFWR1(0), 0x02005574);
        dwc_ddrphy_apb_wr(DDRC_DBG0(0), 0x00000016);
        dwc_ddrphy_apb_wr(DDRC_DBG1(0), 0x00000000);