On Thu, 2016-09-06 at 06:19:15 UTC, "Aneesh Kumar K.V" wrote: > Updated patch below. MMU_FTRS_POWER4 is inherited by others, hence don't > update that. > > >From 4ed66fd24dc4f976969cc34aca8df2ddbc69fe61 Mon Sep 17 00:00:00 2001 > From: "Aneesh Kumar K.V" <aneesh.ku...@linux.vnet.ibm.com> > Date: Sat, 4 Jun 2016 19:58:26 +0530 > Subject: [PATCH] powerpc/mm: Clear top 16 bits of va only on older cpus > > As per ISA, we need to do this only for architecture version 2.02 and > earlier. This continued to work even for 2.07. But let's not do this for > anything after 2.02
What are the practical effects of this? > diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h > index e53ebebff474..fa314b1d667e 100644 > --- a/arch/powerpc/include/asm/mmu.h > +++ b/arch/powerpc/include/asm/mmu.h > @@ -24,6 +24,11 @@ > /* > * This is individual features > */ > +/* > + * We need to clear top 16bits of va (from the remaining 64 bits )in > + * tlbie* instructions > + */ > +#define MMU_FTR_TLBIE_CROP_VA ASM_CONST(0x00008000) > > /* Enable use of high BAT registers */ > #define MMU_FTR_USE_HIGH_BATS ASM_CONST(0x00010000) > @@ -124,7 +129,7 @@ enum { > MMU_FTR_USE_TLBRSRV | MMU_FTR_USE_PAIRED_MAS | > MMU_FTR_NO_SLBIE_B | MMU_FTR_16M_PAGE | MMU_FTR_TLBIEL | > MMU_FTR_LOCKLESS_TLBIE | MMU_FTR_CI_LARGE_PAGE | > - MMU_FTR_1T_SEGMENT | > + MMU_FTR_1T_SEGMENT | MMU_FTR_TLBIE_CROP_VA | > #ifdef CONFIG_PPC_RADIX_MMU > MMU_FTR_RADIX | > #endif > diff --git a/arch/powerpc/kernel/cputable.c b/arch/powerpc/kernel/cputable.c > index eeeacf6235a3..d8a0f7ca74e1 100644 > --- a/arch/powerpc/kernel/cputable.c > +++ b/arch/powerpc/kernel/cputable.c > @@ -137,7 +137,7 @@ static struct cpu_spec __initdata cpu_specs[] = { > .cpu_name = "POWER4 (gp)", > .cpu_features = CPU_FTRS_POWER4, > .cpu_user_features = COMMON_USER_POWER4, > - .mmu_features = MMU_FTRS_POWER4, > + .mmu_features = MMU_FTRS_POWER4 | > MMU_FTR_TLBIE_CROP_VA, > .icache_bsize = 128, > .dcache_bsize = 128, > .num_pmcs = 8, > @@ -152,7 +152,7 @@ static struct cpu_spec __initdata cpu_specs[] = { > .cpu_name = "POWER4+ (gq)", > .cpu_features = CPU_FTRS_POWER4, > .cpu_user_features = COMMON_USER_POWER4, > - .mmu_features = MMU_FTRS_POWER4, > + .mmu_features = MMU_FTRS_POWER4 | > MMU_FTR_TLBIE_CROP_VA, > .icache_bsize = 128, > .dcache_bsize = 128, > .num_pmcs = 8, > @@ -168,7 +168,7 @@ static struct cpu_spec __initdata cpu_specs[] = { > .cpu_features = CPU_FTRS_PPC970, > .cpu_user_features = COMMON_USER_POWER4 | > PPC_FEATURE_HAS_ALTIVEC_COMP, > - .mmu_features = MMU_FTRS_PPC970, > + .mmu_features = MMU_FTRS_PPC970 | > MMU_FTR_TLBIE_CROP_VA, Please add it to MMU_FTRS_PPC970, rather than at every usage. cheers _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev