Re: [Intel-gfx] [PATCH v3 10/16] drm/i915/guc: Convert golden context prep to iosys_map

[Matthew Brost <matthew.brost@intel.com>]

On Wed, Feb 16, 2022 at 09:41:41AM -0800, Lucas De Marchi wrote:
> Use the saved ads_map to prepare the golden context. One difference from
> the init context is that this function can be called before there is a
> gem object (and thus the guc->ads_map) to calculare the size of the
> golden context that should be allocated for that object.
> 
> So in this case the function needs to be prepared for not having the
> system_info with enabled engines filled out. To accomplish that an
> info_map is prepared on the side to point either to the gem object
> or the local variable on the stack. This allows making
> fill_engine_enable_masks() operate always with a iosys_map
> argument.
> 
> Cc: Matt Roper <matthew.d.roper@intel.com>
> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: John Harrison <John.C.Harrison@Intel.com>
> Cc: Matthew Brost <matthew.brost@intel.com>
> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
> Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>

Reviewed-by: Matthew Brost <matthew.brost@intel.com>

> ---
>  drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c | 52 +++++++++++++---------
>  1 file changed, 32 insertions(+), 20 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c
> index d924486490c1..0077a63832ad 100644
> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c
> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c
> @@ -67,6 +67,12 @@ struct __guc_ads_blob {
>  	iosys_map_wr_field(&(guc_)->ads_map, 0, struct __guc_ads_blob,	\
>  			   field_, val_)
>  
> +#define info_map_write(map_, field_, val_) \
> +	iosys_map_wr_field(map_, 0, struct guc_gt_system_info, field_, val_)
> +
> +#define info_map_read(map_, field_) \
> +	iosys_map_rd_field(map_, 0, struct guc_gt_system_info, field_)
> +
>  static u32 guc_ads_regset_size(struct intel_guc *guc)
>  {
>  	GEM_BUG_ON(!guc->ads_regset_size);
> @@ -417,24 +423,24 @@ static void guc_mmio_reg_state_init(struct intel_guc *guc,
>  }
>  
>  static void fill_engine_enable_masks(struct intel_gt *gt,
> -				     struct guc_gt_system_info *info)
> +				     struct iosys_map *info_map)
>  {
> -	info->engine_enabled_masks[GUC_RENDER_CLASS] = 1;
> -	info->engine_enabled_masks[GUC_BLITTER_CLASS] = 1;
> -	info->engine_enabled_masks[GUC_VIDEO_CLASS] = VDBOX_MASK(gt);
> -	info->engine_enabled_masks[GUC_VIDEOENHANCE_CLASS] = VEBOX_MASK(gt);
> +	info_map_write(info_map, engine_enabled_masks[GUC_RENDER_CLASS], 1);
> +	info_map_write(info_map, engine_enabled_masks[GUC_BLITTER_CLASS], 1);
> +	info_map_write(info_map, engine_enabled_masks[GUC_VIDEO_CLASS], VDBOX_MASK(gt));
> +	info_map_write(info_map, engine_enabled_masks[GUC_VIDEOENHANCE_CLASS], VEBOX_MASK(gt));
>  }
>  
>  #define LR_HW_CONTEXT_SIZE (80 * sizeof(u32))
>  #define LRC_SKIP_SIZE (LRC_PPHWSP_SZ * PAGE_SIZE + LR_HW_CONTEXT_SIZE)
> -static int guc_prep_golden_context(struct intel_guc *guc,
> -				   struct __guc_ads_blob *blob)
> +static int guc_prep_golden_context(struct intel_guc *guc)
>  {
>  	struct intel_gt *gt = guc_to_gt(guc);
>  	u32 addr_ggtt, offset;
>  	u32 total_size = 0, alloc_size, real_size;
>  	u8 engine_class, guc_class;
> -	struct guc_gt_system_info *info, local_info;
> +	struct guc_gt_system_info local_info;
> +	struct iosys_map info_map;
>  
>  	/*
>  	 * Reserve the memory for the golden contexts and point GuC at it but
> @@ -448,14 +454,15 @@ static int guc_prep_golden_context(struct intel_guc *guc,
>  	 * GuC will also validate that the LRC base + size fall within the
>  	 * allowed GGTT range.
>  	 */
> -	if (blob) {
> +	if (!iosys_map_is_null(&guc->ads_map)) {
>  		offset = guc_ads_golden_ctxt_offset(guc);
>  		addr_ggtt = intel_guc_ggtt_offset(guc, guc->ads_vma) + offset;
> -		info = &blob->system_info;
> +		info_map = IOSYS_MAP_INIT_OFFSET(&guc->ads_map,
> +						 offsetof(struct __guc_ads_blob, system_info));
>  	} else {
>  		memset(&local_info, 0, sizeof(local_info));
> -		info = &local_info;
> -		fill_engine_enable_masks(gt, info);
> +		iosys_map_set_vaddr(&info_map, &local_info);
> +		fill_engine_enable_masks(gt, &info_map);
>  	}
>  
>  	for (engine_class = 0; engine_class <= MAX_ENGINE_CLASS; ++engine_class) {
> @@ -464,14 +471,14 @@ static int guc_prep_golden_context(struct intel_guc *guc,
>  
>  		guc_class = engine_class_to_guc_class(engine_class);
>  
> -		if (!info->engine_enabled_masks[guc_class])
> +		if (!info_map_read(&info_map, engine_enabled_masks[guc_class]))
>  			continue;
>  
>  		real_size = intel_engine_context_size(gt, engine_class);
>  		alloc_size = PAGE_ALIGN(real_size);
>  		total_size += alloc_size;
>  
> -		if (!blob)
> +		if (iosys_map_is_null(&guc->ads_map))
>  			continue;
>  
>  		/*
> @@ -485,12 +492,15 @@ static int guc_prep_golden_context(struct intel_guc *guc,
>  		 * what comes before it in the context image (which is identical
>  		 * on all engines).
>  		 */
> -		blob->ads.eng_state_size[guc_class] = real_size - LRC_SKIP_SIZE;
> -		blob->ads.golden_context_lrca[guc_class] = addr_ggtt;
> +		ads_blob_write(guc, ads.eng_state_size[guc_class],
> +			       real_size - LRC_SKIP_SIZE);
> +		ads_blob_write(guc, ads.golden_context_lrca[guc_class],
> +			       addr_ggtt);
> +
>  		addr_ggtt += alloc_size;
>  	}
>  
> -	if (!blob)
> +	if (iosys_map_is_null(&guc->ads_map))
>  		return total_size;
>  
>  	GEM_BUG_ON(guc->ads_golden_ctxt_size != total_size);
> @@ -595,13 +605,15 @@ static void __guc_ads_init(struct intel_guc *guc)
>  	struct intel_gt *gt = guc_to_gt(guc);
>  	struct drm_i915_private *i915 = gt->i915;
>  	struct __guc_ads_blob *blob = guc->ads_blob;
> +	struct iosys_map info_map = IOSYS_MAP_INIT_OFFSET(&guc->ads_map,
> +			offsetof(struct __guc_ads_blob, system_info));
>  	u32 base;
>  
>  	/* GuC scheduling policies */
>  	guc_policies_init(guc);
>  
>  	/* System info */
> -	fill_engine_enable_masks(gt, &blob->system_info);
> +	fill_engine_enable_masks(gt, &info_map);
>  
>  	blob->system_info.generic_gt_sysinfo[GUC_GENERIC_GT_SYSINFO_SLICE_ENABLED] =
>  		hweight8(gt->info.sseu.slice_mask);
> @@ -617,7 +629,7 @@ static void __guc_ads_init(struct intel_guc *guc)
>  	}
>  
>  	/* Golden contexts for re-initialising after a watchdog reset */
> -	guc_prep_golden_context(guc, blob);
> +	guc_prep_golden_context(guc);
>  
>  	guc_mapping_table_init(guc_to_gt(guc), &blob->system_info);
>  
> @@ -663,7 +675,7 @@ int intel_guc_ads_create(struct intel_guc *guc)
>  	guc->ads_regset_size = ret;
>  
>  	/* Likewise the golden contexts: */
> -	ret = guc_prep_golden_context(guc, NULL);
> +	ret = guc_prep_golden_context(guc);
>  	if (ret < 0)
>  		return ret;
>  	guc->ads_golden_ctxt_size = ret;
> -- 
> 2.35.1
>