[PATCH 2/2] powerpc/powernv/idle: save-restore DAWR0,DAWRX0 for P10
From: Pratik Rajesh Sampat <hidden>
Date: 2020-07-03 12:47:18
Also in:
lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
Additional registers DAWR0, DAWRX0 may be lost on Power 10 for stop levels < 4. Therefore save the values of these SPRs before entering a "stop" state and restore their values on wakeup. Signed-off-by: Pratik Rajesh Sampat <redacted> --- arch/powerpc/platforms/powernv/idle.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c
index 19d94d021357..471d4a65b1fa 100644
--- a/arch/powerpc/platforms/powernv/idle.c
+++ b/arch/powerpc/platforms/powernv/idle.c@@ -600,6 +600,8 @@ struct p9_sprs { u64 iamr; u64 amor; u64 uamor; + u64 dawr0; + u64 dawrx0; }; static unsigned long power9_idle_stop(unsigned long psscr, bool mmu_on)
@@ -677,6 +679,10 @@ static unsigned long power9_idle_stop(unsigned long psscr, bool mmu_on) sprs.tscr = mfspr(SPRN_TSCR); if (!firmware_has_feature(FW_FEATURE_ULTRAVISOR)) sprs.ldbar = mfspr(SPRN_LDBAR); + if (cpu_has_feature(CPU_FTR_ARCH_31)) { + sprs.dawr0 = mfspr(SPRN_DAWR0); + sprs.dawrx0 = mfspr(SPRN_DAWRX0); + } sprs_saved = true;
@@ -792,6 +798,10 @@ static unsigned long power9_idle_stop(unsigned long psscr, bool mmu_on) mtspr(SPRN_MMCR2, sprs.mmcr2); if (!firmware_has_feature(FW_FEATURE_ULTRAVISOR)) mtspr(SPRN_LDBAR, sprs.ldbar); + if (cpu_has_feature(CPU_FTR_ARCH_31)) { + mtspr(SPRN_DAWR0, sprs.dawr0); + mtspr(SPRN_DAWRX0, sprs.dawrx0); + } mtspr(SPRN_SPRG3, local_paca->sprg_vdso);
--
2.25.4