[PATCH 5.10 442/717] powerpc/perf: Fix Threshold Event Counter Multiplier width for P10

Greg Kroah-Hartman
2020-12-28T14:50:36Z

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

[ Upstream commit ef0e3b650f8ddc54bb70868852f50642ee3ae765 ]

Threshold Event Counter Multiplier (TECM) is part of Monitor Mode
Control Register A (MMCRA). This field along with Threshold Event
Counter Exponent (TECE) is used to get threshould counter value.
In Power10, this is a 8bit field, so patch fixes the
current code to modify the MMCRA[TECM] extraction macro to
handle this change. ISA v3.1 says this is a 7 bit field but
POWER10 it's actually 8 bits which will hopefully be fixed
in ISA v3.1 update.

Fixes: 170a315f41c6 ("powerpc/perf: Support to export MMCRA[TEC*] field to userspace")
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1608022578-1532-1-git-send-email-atrajeev@linux.vnet.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/powerpc/perf/isa207-common.c | 3 +++
arch/powerpc/perf/isa207-common.h | 4 ++++
2 files changed, 7 insertions(+)

diff --git a/arch/powerpc/perf/isa207-common.c b/arch/powerpc/perf/isa207-common.c
index 0f4983ef41036..e1a21d34c6e49 100644
--- a/arch/powerpc/perf/isa207-common.c
+++ b/arch/powerpc/perf/isa207-common.c
@@ -247,6 +247,9 @@ void isa207_get_mem_weight(u64 *weight)
u64 sier = mfspr(SPRN_SIER);
u64 val = (sier & ISA207_SIER_TYPE_MASK) >> ISA207_SIER_TYPE_SHIFT;

+ if (cpu_has_feature(CPU_FTR_ARCH_31))
+ mantissa = P10_MMCRA_THR_CTR_MANT(mmcra);
+
if (val == 0 || val == 7)
*weight = 0;
else
diff --git a/arch/powerpc/perf/isa207-common.h b/arch/powerpc/perf/isa207-common.h
index 42087643c3331..454b32c314406 100644
--- a/arch/powerpc/perf/isa207-common.h
+++ b/arch/powerpc/perf/isa207-common.h
@@ -231,6 +231,10 @@
#define MMCRA_THR_CTR_EXP(v) (((v) >> MMCRA_THR_CTR_EXP_SHIFT) &\
MMCRA_THR_CTR_EXP_MASK)

+#define P10_MMCRA_THR_CTR_MANT_MASK 0xFFul
+#define P10_MMCRA_THR_CTR_MANT(v) (((v) >> MMCRA_THR_CTR_MANT_SHIFT) &\
+ P10_MMCRA_THR_CTR_MANT_MASK)
+
/* MMCRA Threshold Compare bit constant for power9 */
#define p9_MMCRA_THR_CMP_SHIFT 45

--
2.27.0