drm/nv20: Add Z compression support.

Signed-off-by: Francisco Jerez <[e-mail]>
Tested-by: Xavier Chantry <[e-mail]>
Signed-off-by: Ben Skeggs <[e-mail]>

drivers/gpu/drm/nouveau/nouveau_drv.h

···
 	uint32_t addr;
 	uint32_t limit;
 	uint32_t pitch;
+	uint32_t zcomp;
+	struct drm_mm_node *tag_mem;
 	struct nouveau_fence *fence;
 };
 
···
 
 struct nouveau_fb_engine {
 	int num_tiles;
+	struct drm_mm tag_heap;
 
 	int  (*init)(struct drm_device *dev);
 	void (*takedown)(struct drm_device *dev);

drivers/gpu/drm/nouveau/nouveau_reg.h

···
 #	define NV04_PFB_REF_CMD_REFRESH				(1 << 0)
 #define NV04_PFB_PRE						0x001002d4
 #	define NV04_PFB_PRE_CMD_PRECHARGE			(1 << 0)
+#define NV20_PFB_ZCOMP(i)                              (0x00100300 + 4*(i))
+#	define NV20_PFB_ZCOMP_MODE_32				(4 << 24)
+#	define NV20_PFB_ZCOMP_EN				(1 << 31)
+#	define NV25_PFB_ZCOMP_MODE_16				(1 << 20)
+#	define NV25_PFB_ZCOMP_MODE_32				(2 << 20)
 #define NV10_PFB_CLOSE_PAGE2					0x0010033c
 #define NV04_PFB_SCRAMBLE(i)                         (0x00100400 + 4 * (i))
 #define NV40_PFB_TILE(i)                              (0x00100600 + (i*16))
···
 #define NV20_PGRAPH_TLIMIT(i)                              (0x00400904 + (i*16))
 #define NV20_PGRAPH_TSIZE(i)                               (0x00400908 + (i*16))
 #define NV20_PGRAPH_TSTATUS(i)                             (0x0040090C + (i*16))
+#define NV20_PGRAPH_ZCOMP(i)                               (0x00400980 + 4*(i))
 #define NV10_PGRAPH_TILE(i)                                (0x00400B00 + (i*16))
 #define NV10_PGRAPH_TLIMIT(i)                              (0x00400B04 + (i*16))
 #define NV10_PGRAPH_TSIZE(i)                               (0x00400B08 + (i*16))

drivers/gpu/drm/nouveau/nv10_fb.c

···
 #include "nouveau_drv.h"
 #include "nouveau_drm.h"
 
+static struct drm_mm_node *
+nv20_fb_alloc_tag(struct drm_device *dev, uint32_t size)
+{
+	struct drm_nouveau_private *dev_priv = dev->dev_private;
+	struct nouveau_fb_engine *pfb = &dev_priv->engine.fb;
+	struct drm_mm_node *mem;
+	int ret;
+
+	ret = drm_mm_pre_get(&pfb->tag_heap);
+	if (ret)
+		return NULL;
+
+	spin_lock(&dev_priv->tile.lock);
+	mem = drm_mm_search_free(&pfb->tag_heap, size, 0, 0);
+	if (mem)
+		mem = drm_mm_get_block_atomic(mem, size, 0);
+	spin_unlock(&dev_priv->tile.lock);
+
+	return mem;
+}
+
+static void
+nv20_fb_free_tag(struct drm_device *dev, struct drm_mm_node *mem)
+{
+	struct drm_nouveau_private *dev_priv = dev->dev_private;
+
+	spin_lock(&dev_priv->tile.lock);
+	drm_mm_put_block(mem);
+	spin_unlock(&dev_priv->tile.lock);
+}
+
 void
 nv10_fb_init_tile_region(struct drm_device *dev, int i, uint32_t addr,
 			 uint32_t size, uint32_t pitch, uint32_t flags)
 {
 	struct drm_nouveau_private *dev_priv = dev->dev_private;
 	struct nouveau_tile_reg *tile = &dev_priv->tile.reg[i];
+	int bpp = (flags & NOUVEAU_GEM_TILE_32BPP ? 32 : 16);
 
 	tile->addr = addr;
 	tile->limit = max(1u, addr + size) - 1;
 	tile->pitch = pitch;
 
-	if (dev_priv->card_type == NV_20)
-		tile->addr |= 1;
-	else
+	if (dev_priv->card_type == NV_20) {
+		if (flags & NOUVEAU_GEM_TILE_ZETA) {
+			/*
+			 * 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).
+			 */
+			tile->tag_mem = nv20_fb_alloc_tag(dev, size / 256);
+
+			if (tile->tag_mem) {
+				/* Enable Z compression */
+				if (dev_priv->chipset >= 0x25)
+					tile->zcomp = tile->tag_mem->start |
+						(bpp == 16 ?
+						 NV25_PFB_ZCOMP_MODE_16 :
+						 NV25_PFB_ZCOMP_MODE_32);
+				else
+					tile->zcomp = tile->tag_mem->start |
+						NV20_PFB_ZCOMP_EN |
+						(bpp == 16 ? 0 :
+						 NV20_PFB_ZCOMP_MODE_32);
+			}
+
+			tile->addr |= 3;
+		} else {
+			tile->addr |= 1;
+		}
+
+	} else {
 		tile->addr |= 1 << 31;
+	}
 }
 
 void
···
 	struct drm_nouveau_private *dev_priv = dev->dev_private;
 	struct nouveau_tile_reg *tile = &dev_priv->tile.reg[i];
 
-	tile->addr = tile->limit = tile->pitch = 0;
+	if (tile->tag_mem) {
+		nv20_fb_free_tag(dev, tile->tag_mem);
+		tile->tag_mem = NULL;
+	}
+
+	tile->addr = tile->limit = tile->pitch = tile->zcomp = 0;
 }
 
 void
···
 	nv_wr32(dev, NV10_PFB_TLIMIT(i), tile->limit);
 	nv_wr32(dev, NV10_PFB_TSIZE(i), tile->pitch);
 	nv_wr32(dev, NV10_PFB_TILE(i), tile->addr);
+
+	if (dev_priv->card_type == NV_20)
+		nv_wr32(dev, NV20_PFB_ZCOMP(i), tile->zcomp);
 }
 
 int
···
 
 	pfb->num_tiles = NV10_PFB_TILE__SIZE;
 
+	if (dev_priv->card_type == NV_20)
+		drm_mm_init(&pfb->tag_heap, 0,
+			    (dev_priv->chipset >= 0x25 ?
+			     64 * 1024 : 32 * 1024));
+
 	/* Turn all the tiling regions off. */
 	for (i = 0; i < pfb->num_tiles; i++)
 		pfb->set_tile_region(dev, i);
···
 void
 nv10_fb_takedown(struct drm_device *dev)
 {
+	struct drm_nouveau_private *dev_priv = dev->dev_private;
+	struct nouveau_fb_engine *pfb = &dev_priv->engine.fb;
+	int i;
+
+	for (i = 0; i < pfb->num_tiles; i++)
+		pfb->free_tile_region(dev, i);
+
+	if (dev_priv->card_type == NV_20)
+		drm_mm_takedown(&pfb->tag_heap);
 }

drivers/gpu/drm/nouveau/nv20_graph.c

···
 	nv_wr32(dev, NV10_PGRAPH_RDI_DATA, tile->pitch);
 	nv_wr32(dev, NV10_PGRAPH_RDI_INDEX, 0x00EA0010 + 4 * i);
 	nv_wr32(dev, NV10_PGRAPH_RDI_DATA, tile->addr);
+
+	if (dev_priv->card_type == NV_20) {
+		nv_wr32(dev, NV20_PGRAPH_ZCOMP(i), tile->zcomp);
+		nv_wr32(dev, NV10_PGRAPH_RDI_INDEX, 0x00ea0090 + 4 * i);
+		nv_wr32(dev, NV10_PGRAPH_RDI_DATA, tile->zcomp);
+	}
 }
 
 int
···
 	nv_wr32(dev, 0x40009C           , 0x00000040);
 
 	if (dev_priv->chipset >= 0x25) {
-		nv_wr32(dev, 0x400890, 0x00080000);
+		nv_wr32(dev, 0x400890, 0x00a8cfff);
 		nv_wr32(dev, 0x400610, 0x304B1FB6);
-		nv_wr32(dev, 0x400B80, 0x18B82880);
+		nv_wr32(dev, 0x400B80, 0x1cbd3883);
 		nv_wr32(dev, 0x400B84, 0x44000000);
 		nv_wr32(dev, 0x400098, 0x40000080);
 		nv_wr32(dev, 0x400B88, 0x000000ff);
+
 	} else {
-		nv_wr32(dev, 0x400880, 0x00080000); /* 0x0008c7df */
+		nv_wr32(dev, 0x400880, 0x0008c7df);
 		nv_wr32(dev, 0x400094, 0x00000005);
-		nv_wr32(dev, 0x400B80, 0x45CAA208); /* 0x45eae20e */
+		nv_wr32(dev, 0x400B80, 0x45eae20e);
 		nv_wr32(dev, 0x400B84, 0x24000000);
 		nv_wr32(dev, 0x400098, 0x00000040);
 		nv_wr32(dev, NV10_PGRAPH_RDI_INDEX, 0x00E00038);
···
 	for (i = 0; i < NV10_PFB_TILE__SIZE; i++)
 		nv20_graph_set_tile_region(dev, i);
 
-	for (i = 0; i < 8; i++) {
-		nv_wr32(dev, 0x400980 + i * 4, nv_rd32(dev, 0x100300 + i * 4));
-		nv_wr32(dev, NV10_PGRAPH_RDI_INDEX, 0x00EA0090 + i * 4);
-		nv_wr32(dev, NV10_PGRAPH_RDI_DATA,
-					nv_rd32(dev, 0x100300 + i * 4));
-	}
 	nv_wr32(dev, 0x4009a0, nv_rd32(dev, 0x100324));
 	nv_wr32(dev, NV10_PGRAPH_RDI_INDEX, 0x00EA000C);
 	nv_wr32(dev, NV10_PGRAPH_RDI_DATA, nv_rd32(dev, 0x100324));