drm/i915/gvt: adjust high memory size for default vGPU type

Previous high mem size initialized for vGPU type was too small which caused
failure for some VMs. This trys to take minimal value of 384MB for each VM and
enlarge default high mem size to make guest driver happy.
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

drivers/gpu/drm/i915/gvt/vgpu.c

@@ -177,7 +177,7 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
 		if (low_avail / min_low == 0)
 			break;
 		gvt->types[i].low_gm_size = min_low;
-		gvt->types[i].high_gm_size = 3 * gvt->types[i].low_gm_size;
+		gvt->types[i].high_gm_size = max((min_low<<3), MB_TO_BYTES(384U));
 		gvt->types[i].fence = 4;
 		gvt->types[i].max_instance = low_avail / min_low;
 		gvt->types[i].avail_instance = gvt->types[i].max_instance;
@@ -217,7 +217,7 @@ static void intel_gvt_update_vgpu_types(struct intel_gvt *gvt)
 	 */
 	low_gm_avail = MB_TO_BYTES(256) - HOST_LOW_GM_SIZE -
 		gvt->gm.vgpu_allocated_low_gm_size;
-	high_gm_avail = MB_TO_BYTES(256) * 3 - HOST_HIGH_GM_SIZE -
+	high_gm_avail = MB_TO_BYTES(256) * 8UL - HOST_HIGH_GM_SIZE -
 		gvt->gm.vgpu_allocated_high_gm_size;
 	fence_avail = gvt_fence_sz(gvt) - HOST_FENCE -
 		gvt->fence.vgpu_allocated_fence_num;