[Mesa-dev] [PATCH 3/4] intel: Add a flag for miptree mapping to disable transcoding.

[Eric Anholt]

I want to reuse intel_miptree_map() to replace some region mapping that's
broken for separate stencil, but doing so would result in new demands on
ETC transcode that we actually don't want to happen.
---
 src/mesa/drivers/dri/intel/intel_mipmap_tree.c |    8 ++++----
 src/mesa/drivers/dri/intel/intel_mipmap_tree.h |   11 +++++++++++
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/src/mesa/drivers/dri/intel/intel_mipmap_tree.c b/src/mesa/drivers/dri/intel/intel_mipmap_tree.c
index 306cbbe..217f13d 100644
--- a/src/mesa/drivers/dri/intel/intel_mipmap_tree.c
+++ b/src/mesa/drivers/dri/intel/intel_mipmap_tree.c
@@ -1575,9 +1575,9 @@ intel_miptree_map_singlesample(struct intel_context *intel,
 
    if (mt->format == MESA_FORMAT_S8) {
       intel_miptree_map_s8(intel, mt, map, level, slice);
-   } else if (mt->wraps_etc) {
+   } else if (mt->wraps_etc && !(mode & BRW_MAP_DIRECT_BIT)) {
       intel_miptree_map_etc(intel, mt, map, level, slice);
-   } else if (mt->stencil_mt) {
+   } else if (mt->stencil_mt && !(mode & BRW_MAP_DIRECT_BIT)) {
       intel_miptree_map_depthstencil(intel, mt, map, level, slice);
    }
    /* According to the Ivy Bridge PRM, Vol1 Part4, section 1.2.1.2 (Graphics
@@ -1633,9 +1633,9 @@ intel_miptree_unmap_singlesample(struct intel_context *intel,
 
    if (mt->format == MESA_FORMAT_S8) {
       intel_miptree_unmap_s8(intel, mt, map, level, slice);
-   } else if (mt->wraps_etc) {
+   } else if (mt->wraps_etc && !(map->mode & BRW_MAP_DIRECT_BIT)) {
       intel_miptree_unmap_etc(intel, mt, map, level, slice);
-   } else if (mt->stencil_mt) {
+   } else if (mt->stencil_mt && !(map->mode & BRW_MAP_DIRECT_BIT)) {
       intel_miptree_unmap_depthstencil(intel, mt, map, level, slice);
    } else if (map->bo) {
       intel_miptree_unmap_blit(intel, mt, map, level, slice);
diff --git a/src/mesa/drivers/dri/intel/intel_mipmap_tree.h b/src/mesa/drivers/dri/intel/intel_mipmap_tree.h
index 27540bc..acd5e9e 100644
--- a/src/mesa/drivers/dri/intel/intel_mipmap_tree.h
+++ b/src/mesa/drivers/dri/intel/intel_mipmap_tree.h
@@ -66,6 +66,17 @@ extern "C" {
 struct intel_resolve_map;
 struct intel_texture_image;
 
+/**
+ * When calling intel_miptree_map() on an ETC-transcoded-to-RGB miptree or a
+ * depthstencil-split-to-separate-stencil miptree, we'll normally make a
+ * tmeporary and recreate the kind of data requested by Mesa core, since we're
+ * satisfying some glGetTexImage() request or something.
+ *
+ * However, occasionally you want to actually map the miptree's current data
+ * without transcoding back.  This flag to intel_miptree_map() gets you that.
+ */
+#define BRW_MAP_DIRECT_BIT	0x80000000
+
 struct intel_miptree_map {
    /** Bitfield of GL_MAP_READ_BIT, GL_MAP_WRITE_BIT, GL_MAP_INVALIDATE_BIT */
    GLbitfield mode;
-- 
1.7.10.4