lib/sbi_pmu: Don't fallback to fixed counters when sscofpmf && !smcntrpmf

Currently when searching for a hardware counter for an event, if no
programmable counter is available, the code falls back to using a fixed
counter (mcycle/minstret) if one matches the event.

However the fallback is incorrect when sscofpmf is present but
smcntrpmf is not. That's because with sscofpmf, programmable counters
support mode filtering, but the fixed counters do not (without
smcntrpmf). Even if the caller didn't configure mode filtering, by
default programmable counters don't count M mode when sscofpmf is
present, whereas mcycle/minstret do.

Fix the logic to not fallback to a fixed counter if sscofpmf is present
but smcntrpmf is not.

Fixes: 0c304b661965 ("lib: sbi: Allow programmable counters to monitor cycle/instret events")
Signed-off-by: Michael Ellerman <[email protected]>
Reviewed-by: Anup Patel <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Anup Patel <[email protected]>

0 files changed, 0 insertions, 0 deletions