Signed-off-by: Andrew Jones <drjones@xxxxxxxxxx>
---
arm/pmu.c | 26 ++++++++++++++++++--------
errata.txt | 1 +
2 files changed, 19 insertions(+), 8 deletions(-)
diff --git a/arm/pmu.c b/arm/pmu.c
index 74848988a678..1ac692023e5e 100644
--- a/arm/pmu.c
+++ b/arm/pmu.c
@@ -14,6 +14,7 @@
* for more details.
*/
#include "libcflat.h"
+#include "errata.h"
#include "asm/barrier.h"
#include "asm/sysreg.h"
#include "asm/processor.h"
@@ -57,18 +58,12 @@ static inline uint8_t get_pmu_version(void)
static inline uint64_t get_pmccntr(void)
{
- if (pmu_version == 0x3)
- return read_sysreg(PMCCNTR64);
- else
- return read_sysreg(PMCCNTR32);
+ return read_sysreg(PMCCNTR32);
}
static inline void set_pmccntr(uint64_t value)
{
- if (pmu_version == 0x3)
- write_sysreg(value, PMCCNTR64);
- else
- write_sysreg(value & 0xffffffff, PMCCNTR32);
+ write_sysreg(value & 0xffffffff, PMCCNTR32);
}
/* PMCCFILTR is an obsolete name for PMXEVTYPER31 in ARMv7 */
@@ -267,6 +262,19 @@ static bool check_cpi(int cpi)
return true;
}
+static void pmccntr64_test(void)
+{
+#ifdef __arm__
+ if (pmu_version == 0x3) {
+ if (ERRATA(9e3f7a296940)) {
+ write_sysreg(0xdead, PMCCNTR64);
+ report("pmccntr64", read_sysreg(PMCCNTR64) == 0xdead);
+ } else
+ report_skip("Skipping unsafe pmccntr64 test. Set ERRATA_9e3f7a296940=y to enable.");
+ }
+#endif
+}
+
/* Return FALSE if no PMU found, otherwise return TRUE */
bool pmu_probe(void)
{
@@ -293,5 +301,7 @@ int main(int argc, char *argv[])
report("Monotonically increasing cycle count", check_cycles_increase());
report("Cycle/instruction ratio", check_cpi(cpi));
+ pmccntr64_test();
+
return report_summary();
}
diff --git a/errata.txt b/errata.txt
index 95b66c837c63..682d7aa067b9 100644
--- a/errata.txt
+++ b/errata.txt
@@ -2,4 +2,5 @@
# commit : minimum kernel : summary
# 12 hex digits : version :
#---------------:-----------------------:--------------------------------------
+9e3f7a296940 : 4.9 : arm64: KVM: pmu: Fix AArch32 cycle counter access
#---------------:-----------------------:--------------------------------------
--
2.9.4
