Re: [Intel-gfx] [PATCH v6 2/9] drm/i915: Add the has_aux_ccs device property

[Matt Roper <matthew.d.roper@intel.com>]

On Wed, Jul 19, 2023 at 01:07:22PM +0200, Andi Shyti wrote:
> We always assumed that a device might either have AUX or FLAT
> CCS, but this is an approximation that is not always true as it
> requires some further per device checks.
> 
> Add the "has_aux_ccs" flag in the intel_device_info structure in
> order to have a per device flag indicating of the AUX CCS.

I think this flag is a bit misnamed/inaccurate at the moment.  AuxCCS in
general has been around for ages.  Bspec 14276 indicates the GT side of
the hardware has had AuxCCS since at least SNB (gen6).  You seem to just
be setting this flag on the platforms where we need to do TLB
invalidation for the AUX (gen12), which is a small subset of the
platforms that had this compression in general.

I kind of feel like the helper function approach might still be simpler
than using a device flag, but if you want to stick with the flag it's
probably best to rename it slightly so that it more accurately reflects
what we're using it for.


Matt

> 
> Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
> Cc: Matt Roper <matthew.d.roper@intel.com>
> Cc: Jonathan Cavitt <jonathan.cavitt@intel.com>
> Cc: <stable@vger.kernel.org> # v5.8+
> ---
>  drivers/gpu/drm/i915/gt/gen8_engine_cs.c | 4 ++--
>  drivers/gpu/drm/i915/i915_drv.h          | 1 +
>  drivers/gpu/drm/i915/i915_pci.c          | 5 ++++-
>  drivers/gpu/drm/i915/intel_device_info.h | 1 +
>  4 files changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/gt/gen8_engine_cs.c b/drivers/gpu/drm/i915/gt/gen8_engine_cs.c
> index 563efee055602..0d4d5e0407a2d 100644
> --- a/drivers/gpu/drm/i915/gt/gen8_engine_cs.c
> +++ b/drivers/gpu/drm/i915/gt/gen8_engine_cs.c
> @@ -267,7 +267,7 @@ int gen12_emit_flush_rcs(struct i915_request *rq, u32 mode)
>  		else if (engine->class == COMPUTE_CLASS)
>  			flags &= ~PIPE_CONTROL_3D_ENGINE_FLAGS;
>  
> -		if (!HAS_FLAT_CCS(rq->engine->i915))
> +		if (HAS_AUX_CCS(rq->engine->i915))
>  			count = 8 + 4;
>  		else
>  			count = 8;
> @@ -307,7 +307,7 @@ int gen12_emit_flush_xcs(struct i915_request *rq, u32 mode)
>  	if (mode & EMIT_INVALIDATE) {
>  		cmd += 2;
>  
> -		if (!HAS_FLAT_CCS(rq->engine->i915) &&
> +		if (HAS_AUX_CCS(rq->engine->i915) &&
>  		    (rq->engine->class == VIDEO_DECODE_CLASS ||
>  		     rq->engine->class == VIDEO_ENHANCEMENT_CLASS)) {
>  			aux_inv = rq->engine->mask &
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 682ef2b5c7d59..e9cc048b5727a 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -848,6 +848,7 @@ IS_SUBPLATFORM(const struct drm_i915_private *i915,
>   * stored in lmem to support the 3D and media compression formats.
>   */
>  #define HAS_FLAT_CCS(i915)   (INTEL_INFO(i915)->has_flat_ccs)
> +#define HAS_AUX_CCS(i915)    (INTEL_INFO(i915)->has_aux_ccs)
>  
>  #define HAS_GT_UC(i915)	(INTEL_INFO(i915)->has_gt_uc)
>  
> diff --git a/drivers/gpu/drm/i915/i915_pci.c b/drivers/gpu/drm/i915/i915_pci.c
> index fcacdc21643cf..c9ff1d11a9fce 100644
> --- a/drivers/gpu/drm/i915/i915_pci.c
> +++ b/drivers/gpu/drm/i915/i915_pci.c
> @@ -643,7 +643,8 @@ static const struct intel_device_info jsl_info = {
>  	TGL_CACHELEVEL, \
>  	.has_global_mocs = 1, \
>  	.has_pxp = 1, \
> -	.max_pat_index = 3
> +	.max_pat_index = 3, \
> +	.has_aux_ccs = 1
>  
>  static const struct intel_device_info tgl_info = {
>  	GEN12_FEATURES,
> @@ -775,6 +776,7 @@ static const struct intel_device_info dg2_info = {
>  
>  static const struct intel_device_info ats_m_info = {
>  	DG2_FEATURES,
> +	.has_aux_ccs = 1,
>  	.require_force_probe = 1,
>  	.tuning_thread_rr_after_dep = 1,
>  };
> @@ -827,6 +829,7 @@ static const struct intel_device_info mtl_info = {
>  	.__runtime.media.ip.ver = 13,
>  	PLATFORM(INTEL_METEORLAKE),
>  	.extra_gt_list = xelpmp_extra_gt,
> +	.has_aux_ccs = 1,
>  	.has_flat_ccs = 0,
>  	.has_gmd_id = 1,
>  	.has_guc_deprivilege = 1,
> diff --git a/drivers/gpu/drm/i915/intel_device_info.h b/drivers/gpu/drm/i915/intel_device_info.h
> index dbfe6443457b5..93485507506cc 100644
> --- a/drivers/gpu/drm/i915/intel_device_info.h
> +++ b/drivers/gpu/drm/i915/intel_device_info.h
> @@ -151,6 +151,7 @@ enum intel_ppgtt_type {
>  	func(has_reset_engine); \
>  	func(has_3d_pipeline); \
>  	func(has_4tile); \
> +	func(has_aux_ccs); \
>  	func(has_flat_ccs); \
>  	func(has_global_mocs); \
>  	func(has_gmd_id); \
> -- 
> 2.40.1
> 

-- 
Matt Roper
Graphics Software Engineer
Linux GPU Platform Enablement
Intel Corporation