Quoting Mika Kuoppala (2020-12-23 14:56:06)
> Chris Wilson writes:
> > + d_ctx *= RUNTIME_INFO(engine->i915)->cs_timestamp_frequency_hz;
> > + if (IS_ICELAKE(engine->i915))
> > + d_ring *= 1250; /* Fixed 80ns for icl ctx timestamp? */
>
> This is...weird. But I am not goin
Chris Wilson writes:
> We assume that both timestamps are driven off the same clock [reported
> to userspace as I915_PARAM_CS_TIMESTAMP_FREQUENCY]. Verify that this is
> so by reading the timestamp registers around a busywait (on an otherwise
> idle engine so there should be no preemptions).
>
>
We assume that both timestamps are driven off the same clock [reported
to userspace as I915_PARAM_CS_TIMESTAMP_FREQUENCY]. Verify that this is
so by reading the timestamp registers around a busywait (on an otherwise
idle engine so there should be no preemptions).
v2: Icelake (not ehl, nor tgl) see
