drm/xe/xe_migrate: Handle migration logic for xe2+ dgfx

During eviction (vram->sysmem), we use compressed -> uncompressed mapping.
During restore (sysmem->vram), we need to use mapping from
uncompressed -> uncompressed.
Handle logic for selecting the compressed identity map for eviction,
and selecting uncompressed map for restore operations.
v2: Move check of xe_migrate_ccs_emit() before calling
xe_migrate_ccs_copy(). (Nirmoy)

Signed-off-by: Akshata Jahagirdar <[e-mail]>
Reviewed-by: Matthew Auld <[e-mail]>
Reviewed-by: Himal Prasad Ghimiray <[e-mail]>
Signed-off-by: Matt Roper <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/79b3a016e6[e-mail]

drivers/gpu/drm/xe/xe_migrate.c

···
 	struct xe_gt *gt = m->tile->primary_gt;
 	u32 flush_flags = 0;
 
-	if (xe_device_has_flat_ccs(gt_to_xe(gt)) && !copy_ccs && dst_is_indirect) {
+	if (!copy_ccs && dst_is_indirect) {
 		/*
 		 * If the src is already in vram, then it should already
 		 * have been cleared by us, or has been populated by the
···
 	bool copy_ccs = xe_device_has_flat_ccs(xe) &&
 		xe_bo_needs_ccs_pages(src_bo) && xe_bo_needs_ccs_pages(dst_bo);
 	bool copy_system_ccs = copy_ccs && (!src_is_vram || !dst_is_vram);
+	bool use_comp_pat = GRAPHICS_VER(xe) >= 20 && IS_DGFX(xe) && src_is_vram && !dst_is_vram;
 
 	/* Copying CCS between two different BOs is not supported yet. */
 	if (XE_WARN_ON(copy_ccs && src_bo != dst_bo))
···
 		u32 batch_size = 2; /* arb_clear() + MI_BATCH_BUFFER_END */
 		struct xe_sched_job *job;
 		struct xe_bb *bb;
-		u32 flush_flags;
+		u32 flush_flags = 0;
 		u32 update_idx;
 		u64 ccs_ofs, ccs_size;
 		u32 ccs_pt;
···
 		src_L0 = min(src_L0, dst_L0);
 
 		pte_flags = src_is_vram ? PTE_UPDATE_FLAG_IS_VRAM : 0;
+		pte_flags |= use_comp_pat ? PTE_UPDATE_FLAG_IS_COMP_PTE : 0;
 		batch_size += pte_update_size(m, pte_flags, src, &src_it, &src_L0,
 					      &src_L0_ofs, &src_L0_pt, 0, 0,
 					      avail_pts);
···
 
 		/* Add copy commands size here */
 		batch_size += ((copy_only_ccs) ? 0 : EMIT_COPY_DW) +
-			((xe_device_has_flat_ccs(xe) ? EMIT_COPY_CCS_DW : 0));
+			((xe_migrate_needs_ccs_emit(xe) ? EMIT_COPY_CCS_DW : 0));
 
 		bb = xe_bb_new(gt, batch_size, usm);
 		if (IS_ERR(bb)) {
···
 		if (!copy_only_ccs)
 			emit_copy(gt, bb, src_L0_ofs, dst_L0_ofs, src_L0, XE_PAGE_SIZE);
 
-		flush_flags = xe_migrate_ccs_copy(m, bb, src_L0_ofs,
-						  IS_DGFX(xe) ? src_is_vram : src_is_pltt,
-						  dst_L0_ofs,
-						  IS_DGFX(xe) ? dst_is_vram : dst_is_pltt,
-						  src_L0, ccs_ofs, copy_ccs);
+		if (xe_migrate_needs_ccs_emit(xe))
+			flush_flags = xe_migrate_ccs_copy(m, bb, src_L0_ofs,
+							  IS_DGFX(xe) ? src_is_vram : src_is_pltt,
+							  dst_L0_ofs,
+							  IS_DGFX(xe) ? dst_is_vram : dst_is_pltt,
+							  src_L0, ccs_ofs, copy_ccs);
 
 		job = xe_bb_create_migration_job(m->q, bb,
 						 xe_migrate_batch_base(m, usm),