diff mbox series

[kvm-unit-tests,v4,4/4] arm: pmu: Check for overflow in the low counter in chained counters tests

Message ID 20220811185210.234711-5-ricarkol@google.com (mailing list archive)
State New, archived
Headers show
Series arm: pmu: Fixes for bare metal | expand

Commit Message

Ricardo Koller Aug. 11, 2022, 6:52 p.m. UTC
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@redhat.com>
Signed-off-by: Ricardo Koller <ricarkol@google.com>
---
 arm/pmu.c | 33 ++++++++++++++++++---------------
 1 file changed, 18 insertions(+), 15 deletions(-)
diff mbox series

Patch

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