Hi, I have a system booting the 2.6.12-rc3 32bits kernel on an RM9000 processor and I am trying to get my head around how to access up to 2GB of physical memory with a mem=256MB command line booting parameter. I read that on the MIPS kernel this is split 2GB/2GB between kernel and user space, so the kernel should be able to access directly 2GB of physical memory. Kernel drivers will access the memory above 256MB using ioremaps. I need it this way as the memory above 256MB will be used in special ways. What I struggle to understand is whether it would be possible to access all the memory up to 2GB using the ioremap method. The only way I can think of achieving this would be to use ksseg and dynamic TLB entries to access it in 256MB chunks. The fact that I can access ksseg must mean that the kernel is not clearing the TLB entries that the bootloader sets up before launching the kernel, so I would expect to be able to add/remove TLB entries dynamically without affecting the kernel's own memory management. 1) Is there a simpler mechanism to achieve this? 2) Any ill effect on the kernel from the method described above? Many thanks, Alex
