[PATCH v4] drivers/perf: Add support for ARMv8.3-SPE

Wei Li liwei391 at huawei.com
Thu Dec 3 09:16:09 EST 2020


Armv8.3 extends the SPE by adding:
- Alignment field in the Events packet, and filtering on this event
  using PMSEVFR_EL1.
- Support for the Scalable Vector Extension (SVE).

The main additions for SVE are:
- Recording the vector length for SVE operations in the Operation Type
  packet. It is not possible to filter on vector length.
- Incomplete predicate and empty predicate fields in the Events packet,
  and filtering on these events using PMSEVFR_EL1.

Update the check of pmsevfr for empty/partial predicated SVE and
alignment event in SPE driver.

Signed-off-by: Wei Li <liwei391 at huawei.com>
---
v3 -> v4:
 - Return the highest supported version in default in arm_spe_pmsevfr_res0().
 - Drop the exposing of 'pmsver'.
   (Suggested by Will.)
---
v2 -> v3:
 - Make the definition of 'pmsevfr_res0' progressive and easy to check.
   (Suggested by Will.)
---
v1 -> v2:
 - Rename 'pmuver' to 'pmsver', change it's type to 'u16' from 'int'.
   (Suggested by Will and Leo.)
 - Expose 'pmsver' as cap attribute through sysfs, instead of printing.
   (Suggested by Will.)
---
 arch/arm64/include/asm/sysreg.h |  9 ++++++++-
 drivers/perf/arm_spe_pmu.c      | 17 +++++++++++++++--
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index d52c1b3ce589..57e5aee6f7e6 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -287,7 +287,11 @@
 #define SYS_PMSFCR_EL1_ST_SHIFT		18
 
 #define SYS_PMSEVFR_EL1			sys_reg(3, 0, 9, 9, 5)
-#define SYS_PMSEVFR_EL1_RES0		0x0000ffff00ff0f55UL
+#define SYS_PMSEVFR_EL1_RES0_8_2	\
+	(GENMASK_ULL(47, 32) | GENMASK_ULL(23, 16) | GENMASK_ULL(11, 8) |\
+	 BIT_ULL(6) | BIT_ULL(4) | BIT_ULL(2) | BIT_ULL(0))
+#define SYS_PMSEVFR_EL1_RES0_8_3	\
+	(SYS_PMSEVFR_EL1_RES0_8_2 & ~(BIT_ULL(18) | BIT_ULL(17) | BIT_ULL(11)))
 
 #define SYS_PMSLATFR_EL1		sys_reg(3, 0, 9, 9, 6)
 #define SYS_PMSLATFR_EL1_MINLAT_SHIFT	0
@@ -829,6 +833,9 @@
 #define ID_AA64DFR0_PMUVER_8_5		0x6
 #define ID_AA64DFR0_PMUVER_IMP_DEF	0xf
 
+#define ID_AA64DFR0_PMSVER_8_2		0x1
+#define ID_AA64DFR0_PMSVER_8_3		0x2
+
 #define ID_DFR0_PERFMON_SHIFT		24
 
 #define ID_DFR0_PERFMON_8_1		0x4
diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c
index cc00915ad6d1..bce9aff9f546 100644
--- a/drivers/perf/arm_spe_pmu.c
+++ b/drivers/perf/arm_spe_pmu.c
@@ -54,7 +54,7 @@ struct arm_spe_pmu {
 	struct hlist_node			hotplug_node;
 
 	int					irq; /* PPI */
-
+	u16					pmsver;
 	u16					min_period;
 	u16					counter_sz;
 
@@ -655,6 +655,18 @@ static irqreturn_t arm_spe_pmu_irq_handler(int irq, void *dev)
 	return IRQ_HANDLED;
 }
 
+static u64 arm_spe_pmsevfr_res0(u16 pmsver)
+{
+	switch (pmsver) {
+	case ID_AA64DFR0_PMSVER_8_2:
+		return SYS_PMSEVFR_EL1_RES0_8_2;
+	case ID_AA64DFR0_PMSVER_8_3:
+	/* Return the highest version we support in default */
+	default:
+		return SYS_PMSEVFR_EL1_RES0_8_3;
+	}
+}
+
 /* Perf callbacks */
 static int arm_spe_pmu_event_init(struct perf_event *event)
 {
@@ -670,7 +682,7 @@ static int arm_spe_pmu_event_init(struct perf_event *event)
 	    !cpumask_test_cpu(event->cpu, &spe_pmu->supported_cpus))
 		return -ENOENT;
 
-	if (arm_spe_event_to_pmsevfr(event) & SYS_PMSEVFR_EL1_RES0)
+	if (arm_spe_event_to_pmsevfr(event) & arm_spe_pmsevfr_res0(spe_pmu->pmsver))
 		return -EOPNOTSUPP;
 
 	if (attr->exclude_idle)
@@ -937,6 +949,7 @@ static void __arm_spe_pmu_dev_probe(void *info)
 			fld, smp_processor_id());
 		return;
 	}
+	spe_pmu->pmsver = (u16)fld;
 
 	/* Read PMBIDR first to determine whether or not we have access */
 	reg = read_sysreg_s(SYS_PMBIDR_EL1);
-- 
2.17.1




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