powerpc/perf: Add extended regs support for power10 platform

Include capability flag PERF_PMU_CAP_EXTENDED_REGS for power10 and
expose MMCR3, SIER2, SIER3 registers as part of extended regs. Also
introduce PERF_REG_PMU_MASK_31 to define extended mask value at
runtime for power10.

Suggested-by: Ryan Grimm <grimm@linux.ibm.com>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Tested-by: Nageswara R Sastry <nasastry@in.ibm.com>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1596794701-23530-3-git-send-email-atrajeev@linux.vnet.ibm.com

Author: athira-rajeev

arch/powerpc/include/uapi/asm/perf_regs.h

@@ -52,6 +52,9 @@ enum perf_event_powerpc_regs {
 	PERF_REG_POWERPC_MMCR0,
 	PERF_REG_POWERPC_MMCR1,
 	PERF_REG_POWERPC_MMCR2,
+	PERF_REG_POWERPC_MMCR3,
+	PERF_REG_POWERPC_SIER2,
+	PERF_REG_POWERPC_SIER3,
 	/* Max regs without the extended regs */
 	PERF_REG_POWERPC_MAX = PERF_REG_POWERPC_MMCRA + 1,
 };
@@ -60,6 +63,9 @@ enum perf_event_powerpc_regs {
 
 /* PERF_REG_EXTENDED_MASK value for CPU_FTR_ARCH_300 */
 #define PERF_REG_PMU_MASK_300   (((1ULL << (PERF_REG_POWERPC_MMCR2 + 1)) - 1) - PERF_REG_PMU_MASK)
+/* PERF_REG_EXTENDED_MASK value for CPU_FTR_ARCH_31 */
+#define PERF_REG_PMU_MASK_31   (((1ULL << (PERF_REG_POWERPC_SIER3 + 1)) - 1) - PERF_REG_PMU_MASK)
 
 #define PERF_REG_MAX_ISA_300   (PERF_REG_POWERPC_MMCR2 + 1)
+#define PERF_REG_MAX_ISA_31    (PERF_REG_POWERPC_SIER3 + 1)
 #endif /* _UAPI_ASM_POWERPC_PERF_REGS_H */

arch/powerpc/perf/perf_regs.c

@@ -81,6 +81,14 @@ static u64 get_ext_regs_value(int idx)
 		return mfspr(SPRN_MMCR1);
 	case PERF_REG_POWERPC_MMCR2:
 		return mfspr(SPRN_MMCR2);
+#ifdef CONFIG_PPC64
+	case PERF_REG_POWERPC_MMCR3:
+		return mfspr(SPRN_MMCR3);
+	case PERF_REG_POWERPC_SIER2:
+		return mfspr(SPRN_SIER2);
+	case PERF_REG_POWERPC_SIER3:
+		return mfspr(SPRN_SIER3);
+#endif
 	default: return 0;
 	}
 }
@@ -89,7 +97,9 @@ u64 perf_reg_value(struct pt_regs *regs, int idx)
 {
 	u64 perf_reg_extended_max = PERF_REG_POWERPC_MAX;
 
-	if (cpu_has_feature(CPU_FTR_ARCH_300))
+	if (cpu_has_feature(CPU_FTR_ARCH_31))
+		perf_reg_extended_max = PERF_REG_MAX_ISA_31;
+	else if (cpu_has_feature(CPU_FTR_ARCH_300))
 		perf_reg_extended_max = PERF_REG_MAX_ISA_300;
 
 	if (idx == PERF_REG_POWERPC_SIER &&

arch/powerpc/perf/power10-pmu.c

@@ -87,6 +87,8 @@
 #define POWER10_MMCRA_IFM3		0x00000000C0000000UL
 #define POWER10_MMCRA_BHRB_MASK		0x00000000C0000000UL
 
+extern u64 PERF_REG_EXTENDED_MASK;
+
 /* Table of alternatives, sorted by column 0 */
 static const unsigned int power10_event_alternatives[][MAX_ALT] = {
 	{ PM_RUN_CYC_ALT,		PM_RUN_CYC },
@@ -397,6 +399,7 @@ static struct power_pmu power10_pmu = {
 	.cache_events		= &power10_cache_events,
 	.attr_groups		= power10_pmu_attr_groups,
 	.bhrb_nr		= 32,
+	.capabilities           = PERF_PMU_CAP_EXTENDED_REGS,
 };
 
 int init_power10_pmu(void)
@@ -408,6 +411,9 @@ int init_power10_pmu(void)
 	    strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/power10"))
 		return -ENODEV;
 
+	/* Set the PERF_REG_EXTENDED_MASK here */
+	PERF_REG_EXTENDED_MASK = PERF_REG_PMU_MASK_31;
+
 	rc = register_power_pmu(&power10_pmu);
 	if (rc)
 		return rc;