[Intel-xe] [PATCH v2 03/20] drm/xe: Correlate engine and cpu timestamps with better accuracy

[Umesh Nerlige Ramappa]

On Wed, Sep 20, 2023 at 03:29:23PM -0400, Rodrigo Vivi wrote:
>From: Umesh Nerlige Ramappa <umesh.nerlige.ramappa at intel.com>
>
>Perf measurements rely on CPU and engine timestamps to correlate
>events of interest across these time domains. Current mechanisms get
>these timestamps separately and the calculated delta between these
>timestamps lack enough accuracy.
>
>To improve the accuracy of these time measurements to within a few us,
>add a query that returns the engine and cpu timestamps captured as
>close to each other as possible.
>
>Prior work: https://patchwork.freedesktop.org/series/87552/
>
>Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa at intel.com>
>Signed-off-by: Francois Dugast <francois.dugast at intel.com>
>Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
>---

Should already have an R-b from Jose based on this - 
https://patchwork.freedesktop.org/patch/552682/?series=122440&rev=1

Thanks,
Umesh