diff options
| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2020-05-19 05:49:26 +0000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-05-26 22:22:23 +1000 |
| commit | fcdafd10a363cf3278ce29c6c9a92930380c6cd8 (patch) | |
| tree | 09bd40daaf027069f0fc1ee5202bd22dd81865aa /arch/powerpc/Kconfig | |
| parent | da1adea07576722da4597b0df7d00931f0203229 (diff) | |
powerpc/8xx: Allow large TLBs with DEBUG_PAGEALLOC
DEBUG_PAGEALLOC only manages RW data.
Text and RO data can still be mapped with hugepages and pinned TLB.
In order to map with hugepages, also enforce a 512kB data alignment
minimum. That's a trade-off between size of speed, taking into
account that DEBUG_PAGEALLOC is a debug option. Anyway the alignment
is still tunable.
We also allow tuning of alignment for book3s to limit the complexity
of the test in Kconfig that will anyway disappear in the following
patches once DEBUG_PAGEALLOC is handled together with BATs.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c13256f2d356a316715da61fe089b3623ef217a5.1589866984.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/Kconfig')
| -rw-r--r-- | arch/powerpc/Kconfig | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index f5e82629e2cd..fcb0a9ae9872 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -781,8 +781,9 @@ config THREAD_SHIFT config DATA_SHIFT_BOOL bool "Set custom data alignment" depends on ADVANCED_OPTIONS - depends on STRICT_KERNEL_RWX - depends on PPC_BOOK3S_32 || (PPC_8xx && !PIN_TLB_DATA && !PIN_TLB_TEXT) + depends on STRICT_KERNEL_RWX || DEBUG_PAGEALLOC + depends on PPC_BOOK3S_32 || (PPC_8xx && !PIN_TLB_DATA && \ + (!PIN_TLB_TEXT || !STRICT_KERNEL_RWX)) help This option allows you to set the kernel data alignment. When RAM is mapped by blocks, the alignment needs to fit the size and @@ -793,10 +794,12 @@ config DATA_SHIFT_BOOL config DATA_SHIFT int "Data shift" if DATA_SHIFT_BOOL default 24 if STRICT_KERNEL_RWX && PPC64 - range 17 28 if STRICT_KERNEL_RWX && PPC_BOOK3S_32 - range 19 23 if STRICT_KERNEL_RWX && PPC_8xx + range 17 28 if (STRICT_KERNEL_RWX || DEBUG_PAGEALLOC) && PPC_BOOK3S_32 + range 19 23 if (STRICT_KERNEL_RWX || DEBUG_PAGEALLOC) && PPC_8xx default 22 if STRICT_KERNEL_RWX && PPC_BOOK3S_32 default 23 if STRICT_KERNEL_RWX && PPC_8xx + default 23 if DEBUG_PAGEALLOC && PPC_8xx && PIN_TLB_DATA + default 19 if DEBUG_PAGEALLOC && PPC_8xx default PPC_PAGE_SHIFT help On Book3S 32 (603+), DBATs are used to map kernel text and rodata RO. |