Re: [PATCH v2 04/10] powerpc/perf: Add power10_feat to dt_cpu_ftrs

On 08-Jul-2020, at 4:45 PM, Michael Ellerman [off-list ref] wrote:

Athira Rajeev <atrajeev@linux.vnet.ibm.com <mailto:atrajeev@linux.vnet.ibm.com>> writes:

quoted

From: Madhavan Srinivasan <maddy@linux.ibm.com>

Add power10 feature function to dt_cpu_ftrs.c along
with a power10 specific init() to initialize pmu sprs.

Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
---
arch/powerpc/include/asm/reg.h        |  3 +++
arch/powerpc/kernel/cpu_setup_power.S |  7 +++++++
arch/powerpc/kernel/dt_cpu_ftrs.c     | 26 ++++++++++++++++++++++++++
3 files changed, 36 insertions(+)

diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 21a1b2d..900ada1 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h

@@ -1068,6 +1068,9 @@

#define MMCR0_PMC2_LOADMISSTIME	0x5
#endif

+/* BHRB disable bit for PowerISA v3.10 */
+#define MMCRA_BHRB_DISABLE	0x0000002000000000
+
/*
 * SPRG usage:
 *

diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cpu_setup_power.S
index efdcfa7..e8b3370c 100644
--- a/arch/powerpc/kernel/cpu_setup_power.S
+++ b/arch/powerpc/kernel/cpu_setup_power.S

@@ -233,3 +233,10 @@ __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

This doesn't seem like it belongs in this patch. It's not called?

Yes, you are right, this needs to be called from `__setup_cpu_power10`.
Since we didn’t had setup part for power10 in the tree initially, missed it.
I will include this update in V3 

Thanks
Athira

cheers