Re: [PATCH v6 5/9] drm/xe/xe2: Update chunk size for each iteration of ccs copy

["Thomas Hellström" <thomas.hellstrom@linux.intel.com>]

Hi, Himal,

On 12/7/23 10:19, Himal Prasad Ghimiray wrote:
> In xe2 platform XY_CTRL_SURF_COPY_BLT can handle ccs copy for
> max of 1024 main surface pages.
>
> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
> Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
> ---
>   drivers/gpu/drm/xe/xe_migrate.c | 34 ++++++++++++++++++++++++++++-----
>   1 file changed, 29 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c
> index b4dd1b6d78f0..98dca906a023 100644
> --- a/drivers/gpu/drm/xe/xe_migrate.c
> +++ b/drivers/gpu/drm/xe/xe_migrate.c
> @@ -672,11 +672,24 @@ struct dma_fence *xe_migrate_copy(struct xe_migrate *m,
>   		u32 update_idx;
>   		u64 ccs_ofs, ccs_size;
>   		u32 ccs_pt;
> +
>   		bool usm = xe->info.supports_usm;
> +		u32 avail_pts = NUM_PT_PER_BLIT;
>   
>   		src_L0 = xe_migrate_res_sizes(&src_it);
>   		dst_L0 = xe_migrate_res_sizes(&dst_it);
>   
> +		/* In IGFX the XY_CTRL_SURF_COPY_BLT can handle max of 1024
> +		 * pages. Hence limit the processing size to SZ_4M per
> +		 * iteration.
> +		 */
> +		if (!IS_DGFX(xe) && GRAPHICS_VER(xe) >= 20) {
> +			src_L0 = min_t(u64, src_L0, SZ_4M);
> +			dst_L0 = min_t(u64, dst_L0, SZ_4M);
> +
> +			avail_pts = SZ_4M / SZ_2M;
> +		}

Can we limit the size inside xe_migrate_res_sizes() instead?

if (!is_vram)
     if (assume_compressed)
             size = min(size, NUM_COMPRESSED_PAGES_PER_CHUNK);


> +
>   		drm_dbg(&xe->drm, "Pass %u, sizes: %llu & %llu\n",
>   			pass++, src_L0, dst_L0);
>   
> @@ -684,18 +697,18 @@ struct dma_fence *xe_migrate_copy(struct xe_migrate *m,
>   
>   		batch_size += pte_update_size(m, src_is_vram, src, &src_it, &src_L0,
>   					      &src_L0_ofs, &src_L0_pt, 0, 0,
> -					      NUM_PT_PER_BLIT);
> +					      avail_pts);
>   
>   		batch_size += pte_update_size(m, dst_is_vram, dst, &dst_it, &src_L0,
>   					      &dst_L0_ofs, &dst_L0_pt, 0,
> -					      NUM_PT_PER_BLIT, NUM_PT_PER_BLIT);
> +					      avail_pts, avail_pts);
>   
>   		if (copy_system_ccs) {
>   			ccs_size = xe_device_ccs_bytes(xe, src_L0);
>   			batch_size += pte_update_size(m, false, NULL, &ccs_it, &ccs_size,
>   						      &ccs_ofs, &ccs_pt, 0,
> -						      2 * NUM_PT_PER_BLIT,
> -						      NUM_PT_PER_BLIT);
> +						      2 * avail_pts,
> +						      avail_pts);
>   		}
>   
>   		/* Add copy commands size here */
> @@ -923,8 +936,19 @@ struct dma_fence *xe_migrate_clear(struct xe_migrate *m,
>   		struct xe_bb *bb;
>   		u32 batch_size, update_idx;
>   		bool usm = xe->info.supports_usm;
> +		u32 avail_pts = NUM_PT_PER_BLIT;
>   
>   		clear_L0 = xe_migrate_res_sizes(&src_it);
> +
> +		/* In IGFX the XY_CTRL_SURF_COPY_BLT can handle max of 1024
> +		 * pages. Hence limit the processing size to SZ_4M per
> +		 * iteration.
> +		 */
> +		if (!IS_DGFX(xe) && GRAPHICS_VER(xe) >= 20) {
> +			clear_L0 = min_t(u64, clear_L0, SZ_4M);
> +			avail_pts = SZ_4M / SZ_2M;
> +		}
> +
>   		drm_dbg(&xe->drm, "Pass %u, size: %llu\n", pass++, clear_L0);
>   
>   		/* Calculate final sizes and batch size.. */
> @@ -932,7 +956,7 @@ struct dma_fence *xe_migrate_clear(struct xe_migrate *m,
>   			pte_update_size(m, clear_vram, src, &src_it,
>   					&clear_L0, &clear_L0_ofs, &clear_L0_pt,
>   					emit_clear_cmd_len(gt), 0,
> -					NUM_PT_PER_BLIT);
> +					avail_pts);
>   		if (xe_device_has_flat_ccs(xe) && clear_vram)
>   			batch_size += EMIT_COPY_CCS_DW;
>