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| author | Dave Kleikamp <shaggy@linux.vnet.ibm.com> | 2011-01-26 07:17:59 +0100 |
|---|---|---|
| committer | Josh Boyer <jwboyer@linux.vnet.ibm.com> | 2011-02-02 12:59:02 +0100 |
| commit | 21a06b0459f5e3ecdeccacfbf076c229514c1840 (patch) | |
| tree | 2910d16ee073ab722e65eae7373519e64dc5179d /arch | |
| parent | powerpc/476: define specific cpu table entry DD2 core (diff) | |
| download | linux-21a06b0459f5e3ecdeccacfbf076c229514c1840.tar.xz linux-21a06b0459f5e3ecdeccacfbf076c229514c1840.zip | |
powerpc/476: Workaround for PLB6 hang
The 476FP core may hang if an instruction fetch happens during an msync
following a tlbsync. This workaround makes sure that enough instruction
cache lines are pre-fetched before executing the msync. (sync and msync
are the same to the compiler.)
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/mm/tlb_nohash_low.S | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/arch/powerpc/mm/tlb_nohash_low.S b/arch/powerpc/mm/tlb_nohash_low.S index af405eefe48d..7c63c0ed4f1b 100644 --- a/arch/powerpc/mm/tlb_nohash_low.S +++ b/arch/powerpc/mm/tlb_nohash_low.S @@ -189,6 +189,13 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_47x) blr #ifdef CONFIG_PPC_47x + +/* + * 47x variant of icbt + */ +# define ICBT(CT,RA,RB) \ + .long 0x7c00002c | ((CT) << 21) | ((RA) << 16) | ((RB) << 11) + /* * _tlbivax_bcast is only on 47x. We don't bother doing a runtime * check though, it will blow up soon enough if we mistakenly try @@ -206,7 +213,35 @@ _GLOBAL(_tlbivax_bcast) isync eieio tlbsync +BEGIN_FTR_SECTION + b 1f +END_FTR_SECTION_IFSET(CPU_FTR_476_DD2) + sync + wrtee r10 + blr +/* + * DD2 HW could hang if in instruction fetch happens before msync completes. + * Touch enough instruction cache lines to ensure cache hits + */ +1: mflr r9 + bl 2f +2: mflr r6 + li r7,32 + ICBT(0,r6,r7) /* touch next cache line */ + add r6,r6,r7 + ICBT(0,r6,r7) /* touch next cache line */ + add r6,r6,r7 + ICBT(0,r6,r7) /* touch next cache line */ sync + nop + nop + nop + nop + nop + nop + nop + nop + mtlr r9 wrtee r10 blr #endif /* CONFIG_PPC_47x */ |