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

From: Wei Li
Date: Thu Dec 03 2020 - 09:17:19 EST


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@xxxxxxxxxx>
---
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