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authorNicholas Piggin <npiggin@gmail.com>2021-11-23 19:51:47 +1000
committerMichael Ellerman <mpe@ellerman.id.au>2021-11-24 21:08:57 +1100
commit46f9caf1a246a5c0622fa8cc7e673658e925f97e (patch)
tree588a28905c70adcd36e135af702a8e4293b20288 /arch/powerpc/kernel/cpu_setup_power.c
parenteacc818864bb01828280f4d64334c4e5ae6a4daf (diff)
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powerpc/64s: Keep AMOR SPR a constant ~0 at runtime
This register controls supervisor SPR modifications, and as such is only relevant for KVM. KVM always sets AMOR to ~0 on guest entry, and never restores it coming back out to the host, so it can be kept constant and avoid the mtSPR in KVM guest entry. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-10-npiggin@gmail.com
Diffstat (limited to 'arch/powerpc/kernel/cpu_setup_power.c')
-rw-r--r--arch/powerpc/kernel/cpu_setup_power.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/cpu_setup_power.c b/arch/powerpc/kernel/cpu_setup_power.c
index 3cca88ee96d7..a29dc8326622 100644
--- a/arch/powerpc/kernel/cpu_setup_power.c
+++ b/arch/powerpc/kernel/cpu_setup_power.c
@@ -137,6 +137,7 @@ void __setup_cpu_power7(unsigned long offset, struct cpu_spec *t)
return;
mtspr(SPRN_LPID, 0);
+ mtspr(SPRN_AMOR, ~0);
mtspr(SPRN_PCR, PCR_MASK);
init_LPCR_ISA206(mfspr(SPRN_LPCR), LPCR_LPES1 >> LPCR_LPES_SH);
}
@@ -150,6 +151,7 @@ void __restore_cpu_power7(void)
return;
mtspr(SPRN_LPID, 0);
+ mtspr(SPRN_AMOR, ~0);
mtspr(SPRN_PCR, PCR_MASK);
init_LPCR_ISA206(mfspr(SPRN_LPCR), LPCR_LPES1 >> LPCR_LPES_SH);
}
@@ -164,6 +166,7 @@ void __setup_cpu_power8(unsigned long offset, struct cpu_spec *t)
return;
mtspr(SPRN_LPID, 0);
+ mtspr(SPRN_AMOR, ~0);
mtspr(SPRN_PCR, PCR_MASK);
init_LPCR_ISA206(mfspr(SPRN_LPCR) | LPCR_PECEDH, 0); /* LPES = 0 */
init_HFSCR();
@@ -184,6 +187,7 @@ void __restore_cpu_power8(void)
return;
mtspr(SPRN_LPID, 0);
+ mtspr(SPRN_AMOR, ~0);
mtspr(SPRN_PCR, PCR_MASK);
init_LPCR_ISA206(mfspr(SPRN_LPCR) | LPCR_PECEDH, 0); /* LPES = 0 */
init_HFSCR();
@@ -202,6 +206,7 @@ void __setup_cpu_power9(unsigned long offset, struct cpu_spec *t)
mtspr(SPRN_PSSCR, 0);
mtspr(SPRN_LPID, 0);
mtspr(SPRN_PID, 0);
+ mtspr(SPRN_AMOR, ~0);
mtspr(SPRN_PCR, PCR_MASK);
init_LPCR_ISA300((mfspr(SPRN_LPCR) | LPCR_PECEDH | LPCR_PECE_HVEE |\
LPCR_HVICE | LPCR_HEIC) & ~(LPCR_UPRT | LPCR_HR), 0);
@@ -223,6 +228,7 @@ void __restore_cpu_power9(void)
mtspr(SPRN_PSSCR, 0);
mtspr(SPRN_LPID, 0);
mtspr(SPRN_PID, 0);
+ mtspr(SPRN_AMOR, ~0);
mtspr(SPRN_PCR, PCR_MASK);
init_LPCR_ISA300((mfspr(SPRN_LPCR) | LPCR_PECEDH | LPCR_PECE_HVEE |\
LPCR_HVICE | LPCR_HEIC) & ~(LPCR_UPRT | LPCR_HR), 0);
@@ -242,6 +248,7 @@ void __setup_cpu_power10(unsigned long offset, struct cpu_spec *t)
mtspr(SPRN_PSSCR, 0);
mtspr(SPRN_LPID, 0);
mtspr(SPRN_PID, 0);
+ mtspr(SPRN_AMOR, ~0);
mtspr(SPRN_PCR, PCR_MASK);
init_LPCR_ISA300((mfspr(SPRN_LPCR) | LPCR_PECEDH | LPCR_PECE_HVEE |\
LPCR_HVICE | LPCR_HEIC) & ~(LPCR_UPRT | LPCR_HR), 0);
@@ -264,6 +271,7 @@ void __restore_cpu_power10(void)
mtspr(SPRN_PSSCR, 0);
mtspr(SPRN_LPID, 0);
mtspr(SPRN_PID, 0);
+ mtspr(SPRN_AMOR, ~0);
mtspr(SPRN_PCR, PCR_MASK);
init_LPCR_ISA300((mfspr(SPRN_LPCR) | LPCR_PECEDH | LPCR_PECE_HVEE |\
LPCR_HVICE | LPCR_HEIC) & ~(LPCR_UPRT | LPCR_HR), 0);