drm/nouveau/fb: split tile and compression region handling

This is in preparation for extending the support to the remaining
chipsets, to allow for sharing more functions.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/core/include/subdev/fb.h

@@ -84,6 +84,8 @@ struct nouveau_fb {
 		int regions;
 		void (*init)(struct nouveau_fb *, int i, u32 addr, u32 size,
 			     u32 pitch, u32 flags, struct nouveau_fb_tile *);
+		void (*comp)(struct nouveau_fb *, int i, u32 size, u32 flags,
+			     struct nouveau_fb_tile *);
 		void (*fini)(struct nouveau_fb *, int i,
 			     struct nouveau_fb_tile *);
 		void (*prog)(struct nouveau_fb *, int i,

drivers/gpu/drm/nouveau/core/subdev/fb/nv20.c

@@ -34,19 +34,28 @@ static void
 nv20_fb_tile_init(struct nouveau_fb *pfb, int i, u32 addr, u32 size, u32 pitch,
 		  u32 flags, struct nouveau_fb_tile *tile)
 {
-	struct nouveau_device *device = nv_device(pfb);
-	int bpp = (flags & 2) ? 32 : 16;
-
 	tile->addr  = 0x00000001 | addr;
 	tile->limit = max(1u, addr + size) - 1;
 	tile->pitch = pitch;
+	if (flags & 4) {
+		pfb->tile.comp(pfb, i, size, flags, tile);
+		tile->addr |= 2;
+	}
+}
+
+static void
+nv20_fb_tile_comp(struct nouveau_fb *pfb, int i, u32 size, u32 flags,
+		  struct nouveau_fb_tile *tile)
+{
+	struct nouveau_device *device = nv_device(pfb);
+	int bpp = (flags & 2) ? 32 : 16;
 
 	/* Allocate some of the on-die tag memory, used to store Z
 	 * compression meta-data (most likely just a bitmap determining
 	 * if a given tile is compressed or not).
 	 */
 	size /= 256;
-	if (flags & 4) {
+
 	if (!nouveau_mm_head(&pfb->tags, 1, size, size, 1, &tile->tag)) {
 		/* Enable Z compression */
 		tile->zcomp = tile->tag->offset;
@@ -61,9 +70,6 @@ nv20_fb_tile_init(struct nouveau_fb *pfb, int i, u32 addr, u32 size, u32 pitch,
 				tile->zcomp |= 0x04000000;
 		}
 	}
-
-		tile->addr |= 2;
-	}
 }
 
 static void
@@ -119,6 +125,7 @@ nv20_fb_ctor(struct nouveau_object *parent, struct nouveau_object *engine,
 	priv->base.memtype_valid = nv04_fb_memtype_valid;
 	priv->base.tile.regions = 8;
 	priv->base.tile.init = nv20_fb_tile_init;
+	priv->base.tile.comp = nv20_fb_tile_comp;
 	priv->base.tile.fini = nv20_fb_tile_fini;
 	priv->base.tile.prog = nv20_fb_tile_prog;
 	return nouveau_fb_created(&priv->base);