[PATCH 04/13] selftests: KVM: aarch64: Add PMU cycle counter helpers

Raghavendra Rao Ananta rananta at google.com
Mon Feb 13 10:02:25 PST 2023


Add basic helpers for the test to access the cycle counter
registers. The helpers will be used in the upcoming patches
to run the tests related to cycle counter.

No functional change intended.

Signed-off-by: Raghavendra Rao Ananta <rananta at google.com>
---
 .../testing/selftests/kvm/aarch64/vpmu_test.c | 40 +++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/tools/testing/selftests/kvm/aarch64/vpmu_test.c b/tools/testing/selftests/kvm/aarch64/vpmu_test.c
index d72c3c9b9c39f..15aebc7d7dc94 100644
--- a/tools/testing/selftests/kvm/aarch64/vpmu_test.c
+++ b/tools/testing/selftests/kvm/aarch64/vpmu_test.c
@@ -147,6 +147,46 @@ static inline void disable_counter(int idx)
 	isb();
 }
 
+static inline uint64_t read_cycle_counter(void)
+{
+	return read_sysreg(pmccntr_el0);
+}
+
+static inline void reset_cycle_counter(void)
+{
+	uint64_t v = read_sysreg(pmcr_el0);
+
+	write_sysreg(ARMV8_PMU_PMCR_C | v, pmcr_el0);
+	isb();
+}
+
+static inline void enable_cycle_counter(void)
+{
+	uint64_t v = read_sysreg(pmcntenset_el0);
+
+	write_sysreg(ARMV8_PMU_CNTENSET_C | v, pmcntenset_el0);
+	isb();
+}
+
+static inline void disable_cycle_counter(void)
+{
+	uint64_t v = read_sysreg(pmcntenset_el0);
+
+	write_sysreg(ARMV8_PMU_CNTENSET_C | v, pmcntenclr_el0);
+	isb();
+}
+
+static inline void write_pmccfiltr(unsigned long val)
+{
+	write_sysreg(val, pmccfiltr_el0);
+	isb();
+}
+
+static inline uint64_t read_pmccfiltr(void)
+{
+	return read_sysreg(pmccfiltr_el0);
+}
+
 static inline uint64_t get_pmcr_n(void)
 {
 	return FIELD_GET(ARMV8_PMU_PMCR_N, read_sysreg(pmcr_el0));
-- 
2.39.1.581.gbfd45094c4-goog




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