diff options
| author | Michael Ellerman <michael@ellerman.id.au> | 2005-12-05 19:24:33 +0300 |
|---|---|---|
| committer | Paul Mackerras <paulus@samba.org> | 2006-01-09 06:51:54 +0300 |
| commit | b5666f70395016a55cc9d57826508b8a346398d0 (patch) | |
| tree | 39d74718c2bc3f2fcba6456fdc39a6a0de3d78bd /arch/powerpc/mm/slb_low.S | |
| parent | 51fae6de24da57bc6cdaa1b253595c3513ecbf2d (diff) | |
| download | linux-b5666f70395016a55cc9d57826508b8a346398d0.tar.xz | |
[PATCH] powerpc: Separate usage of KERNELBASE and PAGE_OFFSET
This patch separates usage of KERNELBASE and PAGE_OFFSET. I haven't
looked at any of the PPC32 code, if we ever want to support Kdump on
PPC we'll have to do another audit, ditto for iSeries.
This patch makes PAGE_OFFSET the constant, it'll always be 0xC * 1
gazillion for 64-bit.
To get a physical address from a virtual one you subtract PAGE_OFFSET,
_not_ KERNELBASE.
KERNELBASE is the virtual address of the start of the kernel, it's
often the same as PAGE_OFFSET, but _might not be_.
If you want to know something's offset from the start of the kernel
you should subtract KERNELBASE.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/mm/slb_low.S')
| -rw-r--r-- | arch/powerpc/mm/slb_low.S | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/powerpc/mm/slb_low.S b/arch/powerpc/mm/slb_low.S index 950ffc5848c7..d1acee38f163 100644 --- a/arch/powerpc/mm/slb_low.S +++ b/arch/powerpc/mm/slb_low.S @@ -37,9 +37,9 @@ _GLOBAL(slb_allocate_realmode) srdi r9,r3,60 /* get region */ srdi r10,r3,28 /* get esid */ - cmpldi cr7,r9,0xc /* cmp KERNELBASE for later use */ + cmpldi cr7,r9,0xc /* cmp PAGE_OFFSET for later use */ - /* r3 = address, r10 = esid, cr7 = <>KERNELBASE */ + /* r3 = address, r10 = esid, cr7 = <> PAGE_OFFSET */ blt cr7,0f /* user or kernel? */ /* kernel address: proto-VSID = ESID */ @@ -166,7 +166,7 @@ _GLOBAL(slb_allocate_user) /* * Finish loading of an SLB entry and return * - * r3 = EA, r10 = proto-VSID, r11 = flags, clobbers r9, cr7 = <>KERNELBASE + * r3 = EA, r10 = proto-VSID, r11 = flags, clobbers r9, cr7 = <> PAGE_OFFSET */ slb_finish_load: ASM_VSID_SCRAMBLE(r10,r9) |