drm/i915/perf: per-gen timebase for checking sample freq

An oa_exponent_to_ns() utility and per-gen timebase constants where
recently removed when updating the tail pointer race condition WA, and
this restores those so we can update the _PROP_OA_EXPONENT validation
done in read_properties_unlocked() to not assume we have a 12.5MHz
timebase as we did for Haswell.

Accordingly the oa_sample_rate_hard_limit value that's referenced by
proc_dointvec_minmax defining the absolute limit for the OA sampling
frequency is now initialized to (timestamp_frequency / 2) instead of the
6.25MHz constant for Haswell.

v2:
    Specify frequency of 19.2MHz for BXT (Ville)
    Initialize oa_sample_rate_hard_limit per-gen too (Lionel)

Signed-off-by: Robert Bragg <[email protected]>
Signed-off-by: Lionel Landwerlin <[email protected]>
Reviewed-by: Matthew Auld <[email protected]>
Signed-off-by: Ben Widawsky <[email protected]>

0 files changed, 0 insertions, 0 deletions