mt8173: memlayout: Create DRAM DMA region for NOR flash DMA read.

NOR flash has a hardware limitation that it can't access SRAM region
after 4GB mode is enabled. We add a DRAM DMA region after 0x40000000
for NOR flash driver. So that the NOR flash driver can use this region
after 4GB mode is enabled.

TEST=Boot to kernel on rev4 w/ 2GB ram and rev3 w/ 4GB ram.
     And check /proc/meminfo.

Change-Id: Ifedc9e2dfba5d294297b3a28134997ac1dd38f94
Signed-off-by: Yidi Lin <>
Reviewed-by: Julius Werner <>
4 files changed