[Intel-gfx] [PATCH 5/6] drm/i915: Extract i915_cs_timestamp_{ns_to_ticks, tick_to_ns}()

[Chris Wilson]

Quoting Ville Syrjala (2020-03-02 14:39:42)
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Pull the code to do the CS timestamp ns<->ticks conversion into
> helpers and use them all over.

Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
 
> The check in i915_perf_noa_delay_set() seems a bit dubious,
> so we switch it to do what I assume it wanted to do all along
> (ie. make sure the resulting delay in CS timestamp ticks
> doesn't exceed 32bits)?

Yes. The MI_MATH operates on just 32b of the timestamp, and so wants a
delay in that range.
-Chris