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 checking for
overflow. Note that this test fails in KVM without the respective fix.
Reviewed-by: Eric Auger <eric.auger@xxxxxxxxxx>
Signed-off-by: Ricardo Koller <ricarkol@xxxxxxxxxx>
---
arm/pmu.c | 33 ++++++++++++++++++---------------
1 file changed, 18 insertions(+), 15 deletions(-)
diff --git a/arm/pmu.c b/arm/pmu.c
index 756e0d26..cd47b14b 100644
--- a/arm/pmu.c
+++ b/arm/pmu.c
@@ -599,7 +599,7 @@ 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");
+ report(read_sysreg(pmovsclr_el0) == 0x1, "overflow recorded for chained incr #1");
/* test 64b overflow */
@@ -611,7 +611,7 @@ 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) == 0x1, "overflow recorded for chained incr #2");
write_regn_el0(pmevcntr, 0, PRE_OVERFLOW);
write_regn_el0(pmevcntr, 1, ALL_SET);
@@ -619,7 +619,7 @@ 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) == 0x3, "overflow on even and odd counters");
}
static void test_chained_sw_incr(void)
@@ -645,8 +645,9 @@ static void test_chained_sw_incr(void)
write_sysreg(0x1, pmswinc_el0);
isb();
- report(!read_sysreg(pmovsclr_el0) && (read_regn_el0(pmevcntr, 1) == 1),
- "no overflow and chain counter incremented after 100 SW_INCR/CHAIN");
+ report((read_sysreg(pmovsclr_el0) == 0x1) &&
+ (read_regn_el0(pmevcntr, 1) == 1),
+ "overflow and 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));
@@ -664,10 +665,10 @@ static void test_chained_sw_incr(void)
write_sysreg(0x1, pmswinc_el0);
isb();
- report((read_sysreg(pmovsclr_el0) == 0x2) &&
+ report((read_sysreg(pmovsclr_el0) == 0x3) &&
(read_regn_el0(pmevcntr, 1) == 0) &&
(read_regn_el0(pmevcntr, 0) == 84),
- "overflow on chain counter and expected values after 100 SW_INCR/CHAIN");
+ "expected overflows and values 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));
}
@@ -747,8 +748,9 @@ 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) &&
+ (read_sysreg(pmovsclr_el0) == 0x1),
+ "CHAIN counter enabled: CHAIN counter was incremented and overflow");
report_info("CHAIN counter #1 = 0x%lx, overflow=0x%lx",
read_regn_el0(pmevcntr, 1), read_sysreg(pmovsclr_el0));
@@ -775,8 +777,9 @@ 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) &&
+ (read_sysreg(pmovsclr_el0) == 0x1),
+ "32b->64b: CHAIN counter incremented and overflow");
report_info("CHAIN counter #1 = 0x%lx, overflow=0x%lx",
read_regn_el0(pmevcntr, 1), read_sysreg(pmovsclr_el0));
@@ -884,8 +887,8 @@ static void test_overflow_interrupt(void)
write_regn_el0(pmevcntr, 0, PRE_OVERFLOW);
isb();
mem_access_loop(addr, 200, pmu.pmcr_ro | PMU_PMCR_E);
- report(expect_interrupts(0),
- "no overflow interrupt expected on 32b boundary");
+ report(expect_interrupts(0x1),
+ "expect overflow interrupt on 32b boundary");
/* overflow on odd counter */
pmu_reset_stats();
@@ -893,8 +896,8 @@ static void test_overflow_interrupt(void)
write_regn_el0(pmevcntr, 1, ALL_SET);
isb();
mem_access_loop(addr, 400, pmu.pmcr_ro | PMU_PMCR_E);
- report(expect_interrupts(0x2),
- "expect overflow interrupt on odd counter");
+ report(expect_interrupts(0x3),
+ "expect overflow interrupt on even and odd counter");
}
#endif
--
2.37.1.559.g78731f0fdb-goog
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