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 <david@protonic.nl>

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Kumar Gala
2009-03-19 03:55:41 +00:00
committed by Benjamin Herrenschmidt
parent eb3436a013
commit 2319f12395
4 changed files with 45 additions and 7 deletions

View File

@@ -1090,7 +1090,8 @@ static struct cpu_spec __initdata cpu_specs[] = {
.cpu_name = "e300c2",
.cpu_features = CPU_FTRS_E300C2,
.cpu_user_features = PPC_FEATURE_32 | PPC_FEATURE_HAS_MMU,
.mmu_features = MMU_FTR_USE_HIGH_BATS,
.mmu_features = MMU_FTR_USE_HIGH_BATS |
MMU_FTR_NEED_DTLB_SW_LRU,
.icache_bsize = 32,
.dcache_bsize = 32,
.cpu_setup = __setup_cpu_603,
@@ -1103,7 +1104,8 @@ static struct cpu_spec __initdata cpu_specs[] = {
.cpu_name = "e300c3",
.cpu_features = CPU_FTRS_E300,
.cpu_user_features = COMMON_USER,
.mmu_features = MMU_FTR_USE_HIGH_BATS,
.mmu_features = MMU_FTR_USE_HIGH_BATS |
MMU_FTR_NEED_DTLB_SW_LRU,
.icache_bsize = 32,
.dcache_bsize = 32,
.cpu_setup = __setup_cpu_603,
@@ -1118,7 +1120,8 @@ static struct cpu_spec __initdata cpu_specs[] = {
.cpu_name = "e300c4",
.cpu_features = CPU_FTRS_E300,
.cpu_user_features = COMMON_USER,
.mmu_features = MMU_FTR_USE_HIGH_BATS,
.mmu_features = MMU_FTR_USE_HIGH_BATS |
MMU_FTR_NEED_DTLB_SW_LRU,
.icache_bsize = 32,
.dcache_bsize = 32,
.cpu_setup = __setup_cpu_603,