A chained event overflowing on the low counter can set the overflow flag
in PMOVS. KVM does not set it, but real HW and the fast-model seem to.
Moreover, the AArch64.IncrementEventCounter() pseudocode in the ARM ARM
(DDI 0487H.a, J1.1.1 "aarch64/debug") also sets the PMOVS bit on
overflow.
The pmu chain tests fail on bare metal when checking the overflow flag
of the low counter _not_ being set on overflow. Fix by removing the
checks.
Signed-off-by: Ricardo Koller <ricarkol@xxxxxxxxxx>
---
arm/pmu.c | 21 ++++++++++-----------
1 file changed, 10 insertions(+), 11 deletions(-)
diff --git a/arm/pmu.c b/arm/pmu.c
index a7899c3c..4f2c5096 100644
--- a/arm/pmu.c
+++ b/arm/pmu.c
@@ -581,7 +581,6 @@ static void test_chained_counters(void)
precise_instrs_loop(22, pmu.pmcr_ro | PMU_PMCR_E);
report(read_regn_el0(pmevcntr, 1) == 1, "CHAIN counter #1 incremented");
- report(!read_sysreg(pmovsclr_el0), "no overflow recorded for chained incr #1");
/* test 64b overflow */
@@ -593,7 +592,7 @@ static void test_chained_counters(void)
precise_instrs_loop(22, pmu.pmcr_ro | PMU_PMCR_E);
report_info("overflow reg = 0x%lx", read_sysreg(pmovsclr_el0));
report(read_regn_el0(pmevcntr, 1) == 2, "CHAIN counter #1 set to 2");
- report(!read_sysreg(pmovsclr_el0), "no overflow recorded for chained incr #2");
+ report((read_sysreg(pmovsclr_el0) & 0x2) == 0, "no overflow recorded for chained incr #2");
write_regn_el0(pmevcntr, 0, PRE_OVERFLOW);
write_regn_el0(pmevcntr, 1, ALL_SET);
@@ -601,7 +600,7 @@ static void test_chained_counters(void)
precise_instrs_loop(22, pmu.pmcr_ro | PMU_PMCR_E);
report_info("overflow reg = 0x%lx", read_sysreg(pmovsclr_el0));
report(!read_regn_el0(pmevcntr, 1), "CHAIN counter #1 wrapped");
- report(read_sysreg(pmovsclr_el0) == 0x2, "overflow on chain counter");
+ report(read_sysreg(pmovsclr_el0) & 0x2, "overflow on chain counter");
}
static void test_chained_sw_incr(void)
@@ -626,10 +625,10 @@ static void test_chained_sw_incr(void)
for (i = 0; i < 100; i++)
write_sysreg(0x1, pmswinc_el0);
- report(!read_sysreg(pmovsclr_el0) && (read_regn_el0(pmevcntr, 1) == 1),
- "no overflow and chain counter incremented after 100 SW_INCR/CHAIN");
+ report(read_regn_el0(pmevcntr, 1) == 1,
+ "no chain counter incremented after 100 SW_INCR/CHAIN");
report_info("overflow=0x%lx, #0=%ld #1=%ld", read_sysreg(pmovsclr_el0),
- read_regn_el0(pmevcntr, 0), read_regn_el0(pmevcntr, 1));
+ read_regn_el0(pmevcntr, 0), read_regn_el0(pmevcntr, 1));
/* 64b SW_INCR and overflow on CHAIN counter*/
pmu_reset();
@@ -644,7 +643,7 @@ static void test_chained_sw_incr(void)
for (i = 0; i < 100; i++)
write_sysreg(0x1, pmswinc_el0);
- report((read_sysreg(pmovsclr_el0) == 0x2) &&
+ report((read_sysreg(pmovsclr_el0) & 0x2) &&
(read_regn_el0(pmevcntr, 1) == 0) &&
(read_regn_el0(pmevcntr, 0) == 84),
"overflow on chain counter and expected values after 100 SW_INCR/CHAIN");
@@ -727,8 +726,8 @@ static void test_chain_promotion(void)
report_info("MEM_ACCESS counter #0 has value 0x%lx",
read_regn_el0(pmevcntr, 0));
- report((read_regn_el0(pmevcntr, 1) == 1) && !read_sysreg(pmovsclr_el0),
- "CHAIN counter enabled: CHAIN counter was incremented and no overflow");
+ report((read_regn_el0(pmevcntr, 1) == 1),
+ "CHAIN counter enabled: CHAIN counter was incremented");
report_info("CHAIN counter #1 = 0x%lx, overflow=0x%lx",
read_regn_el0(pmevcntr, 1), read_sysreg(pmovsclr_el0));
@@ -755,8 +754,8 @@ static void test_chain_promotion(void)
report_info("MEM_ACCESS counter #0 has value 0x%lx",
read_regn_el0(pmevcntr, 0));
- report((read_regn_el0(pmevcntr, 1) == 1) && !read_sysreg(pmovsclr_el0),
- "32b->64b: CHAIN counter incremented and no overflow");
+ report((read_regn_el0(pmevcntr, 1) == 1),
+ "32b->64b: CHAIN counter incremented");
report_info("CHAIN counter #1 = 0x%lx, overflow=0x%lx",
read_regn_el0(pmevcntr, 1), read_sysreg(pmovsclr_el0));
--
2.37.0.170.g444d1eabd0-goog
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