[v4] powerpc/perf: Initialize power10 PMU registers in cpu setup routine

Athira Rajeev atrajeev at linux.vnet.ibm.com
Thu Jul 23 17:32:37 AEST 2020


Initialize Monitor Mode Control Register 3 (MMCR3)
SPR which is new in power10. For PowerISA v3.1, BHRB disable
is controlled via Monitor Mode Control Register A (MMCRA) bit,
namely "BHRB Recording Disable (BHRBRD)". This patch also initializes
MMCRA BHRBRD to disable BHRB feature at boot for power10.

Signed-off-by: Athira Rajeev <atrajeev at linux.vnet.ibm.com>
---
Dependency:
- On power10 PMU base enablement series V3:
  https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=190462

Changes from v3 -> v4
- Addressed review comments from Jordan and Michael Ellerman.
  This patch was initially part of Power10 PMU base enablement
  series. Moving this as separate patch as suggested by Michael
  Ellerman. Hence dependency of initial series Patch 7 which defines
  MMCRA_BHRB_DISABLE. Addressed review comments from Jordan to make
  sure existing PMU function (__INIT_PMU) will not overwrite ISA 3.1
  updates

Changes from v2 -> v3
- Addressed review comment from Michael Ellerman to
  call PMU init from __setup_cpu_power10

 arch/powerpc/kernel/cpu_setup_power.S | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cpu_setup_power.S
index efdcfa7..3fa6eef 100644
--- a/arch/powerpc/kernel/cpu_setup_power.S
+++ b/arch/powerpc/kernel/cpu_setup_power.S
@@ -94,13 +94,15 @@ _GLOBAL(__restore_cpu_power8)
 _GLOBAL(__setup_cpu_power10)
 	mflr	r11
 	bl	__init_FSCR_power10
+	bl	__init_PMU
+	bl	__init_PMU_ISA31
 	b	1f
 
 _GLOBAL(__setup_cpu_power9)
 	mflr	r11
 	bl	__init_FSCR
-1:	bl	__init_PMU
-	bl	__init_hvmode_206
+	bl	__init_PMU
+1:	bl	__init_hvmode_206
 	mtlr	r11
 	beqlr
 	li	r0,0
@@ -124,13 +126,15 @@ _GLOBAL(__setup_cpu_power9)
 _GLOBAL(__restore_cpu_power10)
 	mflr	r11
 	bl	__init_FSCR_power10
+	bl	__init_PMU
+	bl	__init_PMU_ISA31
 	b	1f
 
 _GLOBAL(__restore_cpu_power9)
 	mflr	r11
 	bl	__init_FSCR
-1:	bl	__init_PMU
-	mfmsr	r3
+	bl	__init_PMU
+1:	mfmsr	r3
 	rldicl.	r0,r3,4,63
 	mtlr	r11
 	beqlr
@@ -233,3 +237,10 @@ __init_PMU_ISA207:
 	li	r5,0
 	mtspr	SPRN_MMCRS,r5
 	blr
+
+__init_PMU_ISA31:
+	li	r5,0
+	mtspr	SPRN_MMCR3,r5
+	LOAD_REG_IMMEDIATE(r5, MMCRA_BHRB_DISABLE)
+	mtspr	SPRN_MMCRA,r5
+	blr
-- 
1.8.3.1



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