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| author |  Christophe Leroy <christophe.leroy@csgroup.eu>
| 2021-02-08 15:10:22 +0000 |
|---|---|---|
| committer |  Michael Ellerman <mpe@ellerman.id.au>
| 2021-02-11 23:35:08 +1100 |
| commit | 76249ddc27080b6b835a89cedcc4185b3b5a6b23 (patch) | |
| tree | 19927679b58d817e90a31e622d3ee778b4297bb8 /arch/powerpc/kernel/head_booke.h | |
| parent | powerpc/32: Always enable data translation on syscall entry (diff) | |
| download | linux-76249ddc27080b6b835a89cedcc4185b3b5a6b23.tar.gz linux-76249ddc27080b6b835a89cedcc4185b3b5a6b23.tar.bz2 linux-76249ddc27080b6b835a89cedcc4185b3b5a6b23.zip | |
powerpc/32: On syscall entry, enable instruction translation at the same time as data
On 40x and 8xx, kernel text is pinned.
On book3s/32, kernel text is mapped by BATs.
Enable instruction translation at the same time as data translation, it
makes things simpler.
MSR_RI can also be set at the same time because srr0/srr1 are already
saved and r1 is set properly.
On booke, translation is always on, so at the end all PPC32
have translation on early.
This reduces null_syscall benchmark by 13 cycles on 8xx
(296 ==> 283 cycles).
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3fe8891c814103a3549efc1d4e7ffc828bba5993.1612796617.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/kernel/head_booke.h')
| -rw-r--r-- | arch/powerpc/kernel/head_booke.h | 7 |
1 files changed, 2 insertions, 5 deletions
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h index 706cd9368992..b3c502c503a0 100644 --- a/arch/powerpc/kernel/head_booke.h +++ b/arch/powerpc/kernel/head_booke.h @@ -157,8 +157,6 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV) stw r12,4(r11) 3: - lis r11, transfer_to_syscall@h - ori r11, r11, transfer_to_syscall@l #ifdef CONFIG_TRACE_IRQFLAGS /* * If MSR is changing we need to keep interrupts disabled at this point @@ -172,9 +170,8 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV) lis r10, (MSR_KERNEL | MSR_EE)@h ori r10, r10, (MSR_KERNEL | MSR_EE)@l #endif - mtspr SPRN_SRR1,r10 - mtspr SPRN_SRR0,r11 - rfi /* jump to handler, enable MMU */ + mtmsr r10 + b transfer_to_syscall /* jump to handler */ 99: b ret_from_kernel_syscall .endm |