We use HIGHMEM on the Au1300 to access any memory spaces >256 MB. Our I/O area starts at 256 MB. We just map the extra DRAM to any area outside the I/O space, enable highmem, and register it as BOOT_MEM_RAM with add_memory_region. Works great. =Kevin -- Kevin Hickey Netlogic Microsystems On Wed, 2009-11-25 at 14:34 +0800, figo zhang wrote: > hi all, > > I am using 24KEC SOC, i want to support larger more than 512MB RAM. > The mips32 architure in Kseg0/Kseg1, > such as: > 0x8000,0000 ~ 0x92c0,0000 # 300MB for RAM > 0x92c0,0000 ~ 0xa000,0000 # 212 for I/O register > > so, mips32 only support 300MB memory, i dont how to support more than > 512MB in linux-mips kernel , such as 2GB memory? it is using HIGHMEM > strategy > for kernel(ZONE_HIGHMEM)? > > Best, > Figo.zhang
