From 88750cb3b60fa1d351a69b35ff10c739f4f4e8ce Mon Sep 17 00:00:00 2001 From: "Ronald G. Minnich" Date: Tue, 16 Jul 2013 17:30:16 -0700 Subject: [PATCH] google/pit: disable SYSMMU for graphics It's not needed and it's a potential problem source. Change-Id: Ic4cafe74e7fc3a9031d852895ad7fd5e5cd64d11 Signed-off-by: Ronald G. Minnich Reviewed-on: https://gerrit.chromium.org/gerrit/62279 Commit-Queue: David Hendricks Reviewed-by: David Hendricks Tested-by: David Hendricks Reviewed-on: http://review.coreboot.org/4410 Tested-by: build bot (Jenkins) Reviewed-by: Patrick Georgi --- src/mainboard/google/pit/mainboard.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/src/mainboard/google/pit/mainboard.c b/src/mainboard/google/pit/mainboard.c index 28704677a6..d0230e26f1 100644 --- a/src/mainboard/google/pit/mainboard.c +++ b/src/mainboard/google/pit/mainboard.c @@ -326,6 +326,15 @@ static void mainboard_init(device_t dev) fb_addr = cbmem_find(CBMEM_ID_CONSOLE); set_vbe_mode_info_valid(&edid, (uintptr_t)fb_addr); + /* + * The reset value for FIMD SYSMMU register MMU_CTRL:0x14640000 + * should be 0 according to the datasheet, but has experimentally + * been found to come up as 3. This means FIMD SYSMMU is on by + * default on Exynos5420. For now we are disabling FIMD SYSMMU. + */ + writel(0x0, (void *)0x14640000); + writel(0x0, (void *)0x14680000); + lcd_vdd(); parade_dp_bridge_setup();