Re: [Intel-gfx] [PATCH 2/8] drm/i915/xehp: CCS shares the render reset domain

[Daniel Vetter <daniel@ffwll.ch>]

On Tue, Sep 07, 2021 at 10:19:10AM -0700, Matt Roper wrote:
> The reset domain is shared between render and all compute engines,
> so resetting one will affect the others.
> 
> Note:  Before performing a reset on an RCS or CCS engine, the GuC will
> attempt to preempt-to-idle the other non-hung RCS/CCS engines to avoid
> impacting other clients (since some shared modules will be reset).  If
> other engines are executing non-preemptable workloads, the impact is
> unavoidable and some work may be lost.
> 
> Bspec: 52549
> Original-patch-by: Michel Thierry
> Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
> Cc: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
> Signed-off-by: Aravind Iddamsetty <aravind.iddamsetty@intel.com>
> Signed-off-by: Matt Roper <matthew.d.roper@intel.com>

Do we have igts validating this all properly?

Specifically that the reset stats are incremented correctly for guilty
respectively victimized contexts.

This is necessary if it doesn't exist yet.

Also you need a patch set here that fixes up the igts which have wrong
assumptions about context isolation.
-Daniel

> ---
>  drivers/gpu/drm/i915/gt/intel_reset.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/gt/intel_reset.c b/drivers/gpu/drm/i915/gt/intel_reset.c
> index 91200c43951f..30598c1d070c 100644
> --- a/drivers/gpu/drm/i915/gt/intel_reset.c
> +++ b/drivers/gpu/drm/i915/gt/intel_reset.c
> @@ -507,6 +507,10 @@ static int gen11_reset_engines(struct intel_gt *gt,
>  		[VECS1] = GEN11_GRDOM_VECS2,
>  		[VECS2] = GEN11_GRDOM_VECS3,
>  		[VECS3] = GEN11_GRDOM_VECS4,
> +		[CCS0] = GEN11_GRDOM_RENDER,
> +		[CCS1] = GEN11_GRDOM_RENDER,
> +		[CCS2] = GEN11_GRDOM_RENDER,
> +		[CCS3] = GEN11_GRDOM_RENDER,
>  	};
>  	struct intel_engine_cs *engine;
>  	intel_engine_mask_t tmp;
> -- 
> 2.25.4
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch