Re: [RFC PATCH 01/43] powerpc/64s: Remove WORT SPR from POWER9/10
Nicholas Piggin writes:
> This register is not architected and not implemented in POWER9 or 10,
> it just reads back zeroes for compatibility.
>
> -78 cycles (9255) cycles POWER9 virt-mode NULL hcall
>
> Signed-off-by: Nicholas Piggin
Reviewed-by: Fabiano Rosas
> ---
> arch/powerpc/kvm/book3s_hv.c | 3 ---
> arch/powerpc/platforms/powernv/idle.c | 2 --
> 2 files changed, 5 deletions(-)
>
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index 9228042bd54f..97f3d6d54b61 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -3640,7 +3640,6 @@ static void load_spr_state(struct kvm_vcpu *vcpu)
> mtspr(SPRN_EBBHR, vcpu->arch.ebbhr);
> mtspr(SPRN_EBBRR, vcpu->arch.ebbrr);
> mtspr(SPRN_BESCR, vcpu->arch.bescr);
> - mtspr(SPRN_WORT, vcpu->arch.wort);
> mtspr(SPRN_TIDR, vcpu->arch.tid);
> mtspr(SPRN_AMR, vcpu->arch.amr);
> mtspr(SPRN_UAMOR, vcpu->arch.uamor);
> @@ -3667,7 +3666,6 @@ static void store_spr_state(struct kvm_vcpu *vcpu)
> vcpu->arch.ebbhr = mfspr(SPRN_EBBHR);
> vcpu->arch.ebbrr = mfspr(SPRN_EBBRR);
> vcpu->arch.bescr = mfspr(SPRN_BESCR);
> - vcpu->arch.wort = mfspr(SPRN_WORT);
> vcpu->arch.tid = mfspr(SPRN_TIDR);
> vcpu->arch.amr = mfspr(SPRN_AMR);
> vcpu->arch.uamor = mfspr(SPRN_UAMOR);
> @@ -3699,7 +3697,6 @@ static void restore_p9_host_os_sprs(struct kvm_vcpu
> *vcpu,
> struct p9_host_os_sprs *host_os_sprs)
> {
> mtspr(SPRN_PSPB, 0);
> - mtspr(SPRN_WORT, 0);
> mtspr(SPRN_UAMOR, 0);
>
> mtspr(SPRN_DSCR, host_os_sprs->dscr);
> diff --git a/arch/powerpc/platforms/powernv/idle.c
> b/arch/powerpc/platforms/powernv/idle.c
> index 528a7e0cf83a..180baecad914 100644
> --- a/arch/powerpc/platforms/powernv/idle.c
> +++ b/arch/powerpc/platforms/powernv/idle.c
> @@ -667,7 +667,6 @@ static unsigned long power9_idle_stop(unsigned long psscr)
> sprs.purr = mfspr(SPRN_PURR);
> sprs.spurr = mfspr(SPRN_SPURR);
> sprs.dscr = mfspr(SPRN_DSCR);
> - sprs.wort = mfspr(SPRN_WORT);
> sprs.ciabr = mfspr(SPRN_CIABR);
>
> sprs.mmcra = mfspr(SPRN_MMCRA);
> @@ -785,7 +784,6 @@ static unsigned long power9_idle_stop(unsigned long psscr)
> mtspr(SPRN_PURR,sprs.purr);
> mtspr(SPRN_SPURR, sprs.spurr);
> mtspr(SPRN_DSCR,sprs.dscr);
> - mtspr(SPRN_WORT,sprs.wort);
> mtspr(SPRN_CIABR, sprs.ciabr);
>
> mtspr(SPRN_MMCRA, sprs.mmcra);
[RFC PATCH 01/43] powerpc/64s: Remove WORT SPR from POWER9/10
This register is not architected and not implemented in POWER9 or 10,
it just reads back zeroes for compatibility.
-78 cycles (9255) cycles POWER9 virt-mode NULL hcall
Signed-off-by: Nicholas Piggin
---
arch/powerpc/kvm/book3s_hv.c | 3 ---
arch/powerpc/platforms/powernv/idle.c | 2 --
2 files changed, 5 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 9228042bd54f..97f3d6d54b61 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3640,7 +3640,6 @@ static void load_spr_state(struct kvm_vcpu *vcpu)
mtspr(SPRN_EBBHR, vcpu->arch.ebbhr);
mtspr(SPRN_EBBRR, vcpu->arch.ebbrr);
mtspr(SPRN_BESCR, vcpu->arch.bescr);
- mtspr(SPRN_WORT, vcpu->arch.wort);
mtspr(SPRN_TIDR, vcpu->arch.tid);
mtspr(SPRN_AMR, vcpu->arch.amr);
mtspr(SPRN_UAMOR, vcpu->arch.uamor);
@@ -3667,7 +3666,6 @@ static void store_spr_state(struct kvm_vcpu *vcpu)
vcpu->arch.ebbhr = mfspr(SPRN_EBBHR);
vcpu->arch.ebbrr = mfspr(SPRN_EBBRR);
vcpu->arch.bescr = mfspr(SPRN_BESCR);
- vcpu->arch.wort = mfspr(SPRN_WORT);
vcpu->arch.tid = mfspr(SPRN_TIDR);
vcpu->arch.amr = mfspr(SPRN_AMR);
vcpu->arch.uamor = mfspr(SPRN_UAMOR);
@@ -3699,7 +3697,6 @@ static void restore_p9_host_os_sprs(struct kvm_vcpu *vcpu,
struct p9_host_os_sprs *host_os_sprs)
{
mtspr(SPRN_PSPB, 0);
- mtspr(SPRN_WORT, 0);
mtspr(SPRN_UAMOR, 0);
mtspr(SPRN_DSCR, host_os_sprs->dscr);
diff --git a/arch/powerpc/platforms/powernv/idle.c
b/arch/powerpc/platforms/powernv/idle.c
index 528a7e0cf83a..180baecad914 100644
--- a/arch/powerpc/platforms/powernv/idle.c
+++ b/arch/powerpc/platforms/powernv/idle.c
@@ -667,7 +667,6 @@ static unsigned long power9_idle_stop(unsigned long psscr)
sprs.purr = mfspr(SPRN_PURR);
sprs.spurr = mfspr(SPRN_SPURR);
sprs.dscr = mfspr(SPRN_DSCR);
- sprs.wort = mfspr(SPRN_WORT);
sprs.ciabr = mfspr(SPRN_CIABR);
sprs.mmcra = mfspr(SPRN_MMCRA);
@@ -785,7 +784,6 @@ static unsigned long power9_idle_stop(unsigned long psscr)
mtspr(SPRN_PURR,sprs.purr);
mtspr(SPRN_SPURR, sprs.spurr);
mtspr(SPRN_DSCR,sprs.dscr);
- mtspr(SPRN_WORT,sprs.wort);
mtspr(SPRN_CIABR, sprs.ciabr);
mtspr(SPRN_MMCRA, sprs.mmcra);
--
2.23.0
