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| author | Joakim Tjernlund <joakim.tjernlund@transmode.se> | 2009-12-29 05:10:58 +0000 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2010-01-15 13:20:07 +1100 |
| commit | 9f4f04ba2b117a5c741d019629d7ffccdc621122 (patch) | |
| tree | 3a96a7c0263b01b4706a665e9d9cbfc76d3f7011 /arch/powerpc/kernel/head_8xx.S | |
| parent | 004b35063296b6772fa72404a35b498f1e71e87e (diff) | |
| download | linux-9f4f04ba2b117a5c741d019629d7ffccdc621122.tar.gz linux-9f4f04ba2b117a5c741d019629d7ffccdc621122.tar.bz2 linux-9f4f04ba2b117a5c741d019629d7ffccdc621122.zip | |
powerpc/8xx: Always pin kernel instruction TLB
Various kernel asm modifies SRR0/SRR1 just before executing
a rfi. If such code crosses a page boundary you risk a TLB miss
which will clobber SRR0/SRR1. Avoid this by always pinning
kernel instruction TLB space.
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/kernel/head_8xx.S')
| -rw-r--r-- | arch/powerpc/kernel/head_8xx.S | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index 678f98cd5e64..a2ed3422fa3d 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -768,12 +768,12 @@ start_here: */ initial_mmu: tlbia /* Invalidate all TLB entries */ -#ifdef CONFIG_PIN_TLB +/* Always pin the first 8 MB ITLB to prevent ITLB + misses while mucking around with SRR0/SRR1 in asm +*/ lis r8, MI_RSV4I@h ori r8, r8, 0x1c00 -#else - li r8, 0 -#endif + mtspr SPRN_MI_CTR, r8 /* Set instruction MMU control */ #ifdef CONFIG_PIN_TLB |