lib: pmu: check SSCOF before masking

We should check if SSCOF extension is present,
before applying inhibit mask and clearing overflow,
otherwise undesirable value can be written
in MHPMEVENT_N CSR.

Signed-off-by: Nikita Shubin <n.shubin@yadro.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>

diff --git a/lib/sbi/sbi_pmu.c b/lib/sbi/sbi_pmu.c
index 10668a3..5b845f8 100644 (file)
--- a/lib/sbi/sbi_pmu.c
+++ b/lib/sbi/sbi_pmu.c
@@ -467,7 +467,8 @@ static int pmu_update_hw_mhpmevent(struct sbi_pmu_hw_event *hw_evt, int ctr_idx,
                return SBI_EFAIL;
 
        /* Always clear the OVF bit and inhibit countin of events in M-mode */
-       mhpmevent_val = (mhpmevent_val & ~MHPMEVENT_SSCOF_MASK) | MHPMEVENT_MINH;
+       if (sbi_hart_has_feature(scratch, SBI_HART_HAS_SSCOFPMF))
+               mhpmevent_val = (mhpmevent_val & ~MHPMEVENT_SSCOF_MASK) | MHPMEVENT_MINH;
 
        /* Update the inhibit flags based on inhibit flags received from supervisor */
        pmu_update_inhibit_flags(flags, &mhpmevent_val);