drm/i915/gvt: adjust to fixed vGPU types

Previous vGPU type create tried to determine vGPU type name e.g _1, _2
based on the number of mdev devices can be created, but different type
might have very different resource size depending on physical device.
We need to split type name vs. actual mdev resource and create fixed
vGPU type with determined size for consistence.

With this we'd like to fix vGPU types for _1, _2, _4 and _8 now, each
type has fixed defined resource size. Available mdev instances that could
be created is determined by physical resource, and user should query
for that before creating.

Cc: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

drivers/gpu/drm/i915/gvt/gvt.h

@@ -212,7 +212,6 @@ struct intel_gvt_opregion {
 #define NR_MAX_INTEL_VGPU_TYPES 20
 struct intel_vgpu_type {
 	char name[16];
-	unsigned int max_instance;
 	unsigned int avail_instance;
 	unsigned int low_gm_size;
 	unsigned int high_gm_size;

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

@@ -64,6 +64,19 @@ void populate_pvinfo_page(struct intel_vgpu *vgpu)
 	WARN_ON(sizeof(struct vgt_if) != VGT_PVINFO_SIZE);
 }
 
+static struct {
+	unsigned int low_mm;
+	unsigned int high_mm;
+	unsigned int fence;
+	char *name;
+} vgpu_types[] = {
+/* Fixed vGPU type table */
+	{ MB_TO_BYTES(64), MB_TO_BYTES(512), 4, "8" },
+	{ MB_TO_BYTES(128), MB_TO_BYTES(512), 4, "4" },
+	{ MB_TO_BYTES(256), MB_TO_BYTES(1024), 4, "2" },
+	{ MB_TO_BYTES(512), MB_TO_BYTES(2048), 4, "1" },
+};
+
 /**
  * intel_gvt_init_vgpu_types - initialize vGPU type list
  * @gvt : GVT device
@@ -78,9 +91,8 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
 	unsigned int min_low;
 
 	/* vGPU type name is defined as GVTg_Vx_y which contains
-	 * physical GPU generation type and 'y' means maximum vGPU
-	 * instances user can create on one physical GPU for this
-	 * type.
+	 * physical GPU generation type (e.g V4 as BDW server, V5 as
+	 * SKL server).
 	 *
 	 * Depend on physical SKU resource, might see vGPU types like
 	 * GVTg_V4_8, GVTg_V4_4, GVTg_V4_2, etc. We can create
@@ -92,7 +104,7 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
 	 */
 	low_avail = gvt_aperture_sz(gvt) - HOST_LOW_GM_SIZE;
 	high_avail = gvt_hidden_sz(gvt) - HOST_HIGH_GM_SIZE;
-	num_types = 4;
+	num_types = sizeof(vgpu_types) / sizeof(vgpu_types[0]);
 
 	gvt->types = kzalloc(num_types * sizeof(struct intel_vgpu_type),
 			     GFP_KERNEL);
@@ -101,25 +113,24 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
 
 	min_low = MB_TO_BYTES(32);
 	for (i = 0; i < num_types; ++i) {
-		if (low_avail / min_low == 0)
+		if (low_avail / vgpu_types[i].low_mm == 0)
 			break;
-		gvt->types[i].low_gm_size = min_low;
-		gvt->types[i].high_gm_size = max((min_low<<3), MB_TO_BYTES(384U));
-		gvt->types[i].fence = 4;
-		gvt->types[i].max_instance = min(low_avail / min_low,
-						 high_avail / gvt->types[i].high_gm_size);
-		gvt->types[i].avail_instance = gvt->types[i].max_instance;
+
+		gvt->types[i].low_gm_size = vgpu_types[i].low_mm;
+		gvt->types[i].high_gm_size = vgpu_types[i].high_mm;
+		gvt->types[i].fence = vgpu_types[i].fence;
+		gvt->types[i].avail_instance = min(low_avail / vgpu_types[i].low_mm,
+						   high_avail / vgpu_types[i].high_mm);
 
 		if (IS_GEN8(gvt->dev_priv))
-			sprintf(gvt->types[i].name, "GVTg_V4_%u",
-						gvt->types[i].max_instance);
+			sprintf(gvt->types[i].name, "GVTg_V4_%s",
+						vgpu_types[i].name);
 		else if (IS_GEN9(gvt->dev_priv))
-			sprintf(gvt->types[i].name, "GVTg_V5_%u",
-						gvt->types[i].max_instance);
+			sprintf(gvt->types[i].name, "GVTg_V5_%s",
+						vgpu_types[i].name);
 
-		min_low <<= 1;
-		gvt_dbg_core("type[%d]: %s max %u avail %u low %u high %u fence %u\n",
-			     i, gvt->types[i].name, gvt->types[i].max_instance,
+		gvt_dbg_core("type[%d]: %s avail %u low %u high %u fence %u\n",
+			     i, gvt->types[i].name,
 			     gvt->types[i].avail_instance,
 			     gvt->types[i].low_gm_size,
 			     gvt->types[i].high_gm_size, gvt->types[i].fence);
@@ -138,7 +149,7 @@ static void intel_gvt_update_vgpu_types(struct intel_gvt *gvt)
 {
 	int i;
 	unsigned int low_gm_avail, high_gm_avail, fence_avail;
-	unsigned int low_gm_min, high_gm_min, fence_min, total_min;
+	unsigned int low_gm_min, high_gm_min, fence_min;
 
 	/* Need to depend on maxium hw resource size but keep on
 	 * static config for now.
@@ -154,12 +165,11 @@ static void intel_gvt_update_vgpu_types(struct intel_gvt *gvt)
 		low_gm_min = low_gm_avail / gvt->types[i].low_gm_size;
 		high_gm_min = high_gm_avail / gvt->types[i].high_gm_size;
 		fence_min = fence_avail / gvt->types[i].fence;
-		total_min = min(min(low_gm_min, high_gm_min), fence_min);
-		gvt->types[i].avail_instance = min(gvt->types[i].max_instance,
-						   total_min);
+		gvt->types[i].avail_instance = min(min(low_gm_min, high_gm_min),
+						   fence_min);
 
-		gvt_dbg_core("update type[%d]: %s max %u avail %u low %u high %u fence %u\n",
-		       i, gvt->types[i].name, gvt->types[i].max_instance,
+		gvt_dbg_core("update type[%d]: %s avail %u low %u high %u fence %u\n",
+		       i, gvt->types[i].name,
 		       gvt->types[i].avail_instance, gvt->types[i].low_gm_size,
 		       gvt->types[i].high_gm_size, gvt->types[i].fence);
 	}