From 2319f1239592d0de80414ad2338c2bd7384a2a41 Mon Sep 17 00:00:00 2001 From: Kumar Gala Date: Thu, 19 Mar 2009 03:55:41 +0000 Subject: powerpc/mm: e300c2/c3/c4 TLB errata workaround Complete workaround for DTLB errata in e300c2/c3/c4 processors. Due to the bug, the hardware-implemented LRU algorythm always goes to way 1 of the TLB. This fix implements the proposed software workaround in form of a LRW table for chosing the TLB-way. Based on patch from David Jander Signed-off-by: Kumar Gala Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/mmu.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'arch/powerpc/include') diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h index dc82dcd06ae..c073de4af84 100644 --- a/arch/powerpc/include/asm/mmu.h +++ b/arch/powerpc/include/asm/mmu.h @@ -46,6 +46,12 @@ */ #define MMU_FTR_LOCK_BCAST_INVAL ASM_CONST(0x00100000) +/* This indicates that the processor doesn't handle way selection + * properly and needs SW to track and update the LRU state. This + * is specific to an errata on e300c2/c3/c4 class parts + */ +#define MMU_FTR_NEED_DTLB_SW_LRU ASM_CONST(0x00200000) + #ifndef __ASSEMBLY__ #include -- cgit v1.2.3