From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
To: Michael Ellerman <mpe@ellerman.id.au>,
benh@kernel.crashing.org, paulus@samba.org
Cc: linuxppc-dev@lists.ozlabs.org
Subject: Re: [V2, 08/10] powerpc/mm: Clear top 16 bits of va only on older cpus
Date: Tue, 14 Jun 2016 12:43:52 +0530 [thread overview]
Message-ID: <878ty8utsf.fsf@skywalker.in.ibm.com> (raw)
In-Reply-To: <3rTHSj5DMRz9t0G@ozlabs.org>
Michael Ellerman <mpe@ellerman.id.au> writes:
> 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.kumar@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?
For ISA 3.0 we require these top bits to be not cleared. I have updated
the commit message to reflect that.
>
>> 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.
>
Done
-aneesh
next prev parent reply other threads:[~2016-06-14 7:14 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-08 14:25 [PATCH V2 00/10] Fixes for Radix support Aneesh Kumar K.V
2016-06-08 14:25 ` [PATCH V2 01/10] Fix .long's in mm/tlb-radix.c to more meaningful Aneesh Kumar K.V
2016-06-08 14:25 ` [PATCH V2 02/10] powerpc/mm/radix: Update to tlb functions ric argument Aneesh Kumar K.V
2016-06-15 12:37 ` [V2, " Michael Ellerman
2016-06-08 14:25 ` [PATCH V2 03/10] powerpc/mm/radix: Flush page walk cache when freeing page table Aneesh Kumar K.V
2016-06-15 12:37 ` [V2, " Michael Ellerman
2016-06-08 14:25 ` [PATCH V2 04/10] powerpc/mm/radix: Update LPCR HR bit as per ISA Aneesh Kumar K.V
2016-06-08 14:25 ` [PATCH V2 05/10] powerpc/mm: use _raw variant of page table accessors Aneesh Kumar K.V
2016-06-08 14:25 ` [PATCH V2 06/10] powerpc/mm: Compile out radix related functions if RADIX_MMU is disabled Aneesh Kumar K.V
2016-06-08 14:25 ` [PATCH V2 07/10] powerpc/hash: Use the correct ppp mask when updating hpte Aneesh Kumar K.V
2016-06-15 12:37 ` [V2, " Michael Ellerman
2016-06-08 14:25 ` [PATCH V2 08/10] powerpc/mm: Clear top 16 bits of va only on older cpus Aneesh Kumar K.V
2016-06-09 6:19 ` Aneesh Kumar K.V
2016-06-14 4:57 ` [V2, " Michael Ellerman
2016-06-14 7:13 ` Aneesh Kumar K.V [this message]
2016-06-08 14:25 ` [PATCH V2 09/10] powerpc/mm: Print formation regarding the the MMU mode Aneesh Kumar K.V
2016-06-08 14:25 ` [PATCH V2 10/10] powerpc/mm/hash: Update SDR1 size encoding as documented in ISA 3.0 Aneesh Kumar K.V
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