[igt-dev] [PATCH i-g-t 71/79] lib/i915: Rework engine API availability checks (v2)

[Dixit, Ashutosh]

On Thu, 17 Jun 2021 12:15:08 -0700, Jason Ekstrand wrote:
>
>  bool gem_has_engine_topology(int fd)
>  {
> -	struct drm_i915_gem_context_param param = {
> -		.param = I915_CONTEXT_PARAM_ENGINES,
> -	};
> -
> -	return !__gem_context_get_param(fd, &param);
> +	struct intel_engine_data ed;
> +	return !__query_engine_list(fd, &ed);

Is this correct? Isn't this actually a check for the presence of
I915_CONTEXT_PARAM_ENGINES (seems so looking from which this is called)? So
we could probably just create a new context and do a set_engines on it and
return true if that succeeded? Or do that in addition to
__query_engine_list? Maybe intel_ctx_create_all_physical() will do both?
Thanks.