[OpenBIOS] [PATCH] sparc64 add mmu translate and unmap methods

[Igor Kovalenko]

Hi!

This patch enables mmu methonds "translate" and "unmap" for sparc64.

Helper function spitfire_translate walks through dtlb entries and
performs phys to virt translation. Two other helpers itlb_demap and
dtlb_demap perform actual tlb entry demapping. It is then easy to
implement unmap_pages() which is the reverse of map_pages(), and
enable mmu_unmap as the result.

I tested these changes to work with qemu-system-sparc64 loading gentoo
2008.0 iso image.
qemu is currently lacking spitfire demap ASI support which I'll post
there shortly.

Please apply.