powerpc/perf: Add restrictions to PMC5 in power9 DD1

[ Upstream commit 8d911904 ]

PMC5 on POWER9 DD1 may not provide right counts in all
sampling scenarios, hence use PM_INST_DISP event instead
in PMC2 or PMC3 in preference.
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/powerpc/perf/isa207-common.h

@@ -201,6 +201,10 @@
 	CNST_PMC_VAL(1) | CNST_PMC_VAL(2) | CNST_PMC_VAL(3) | \
 	CNST_PMC_VAL(4) | CNST_PMC_VAL(5) | CNST_PMC_VAL(6) | CNST_NC_VAL
 
+/*
+ * Lets restrict use of PMC5 for instruction counting.
+ */
+#define P9_DD1_TEST_ADDER	(ISA207_TEST_ADDER | CNST_PMC_VAL(5))
 
 /* Bits in MMCR1 for PowerISA v2.07 */
 #define MMCR1_UNIT_SHIFT(pmc)		(60 - (4 * ((pmc) - 1)))

arch/powerpc/perf/power9-pmu.c

@@ -295,7 +295,7 @@ static struct power_pmu power9_pmu = {
 	.name			= "POWER9",
 	.n_counter		= MAX_PMU_COUNTERS,
 	.add_fields		= ISA207_ADD_FIELDS,
-	.test_adder		= ISA207_TEST_ADDER,
+	.test_adder		= P9_DD1_TEST_ADDER,
 	.compute_mmcr		= isa207_compute_mmcr,
 	.config_bhrb		= power9_config_bhrb,
 	.bhrb_filter_map	= power9_bhrb_filter_map,