i915: Add GBM_BO_USE_HW_VIDEO_DECODER use flag

This flag is used to indicate that the platform video decoder will be
writing into this buffer and that it should be allocated
accordingly. On Intel, this means that we have to allocate y-tiled
NV12 for libva to be able to decode to the buffer.

We force gralloc NV12 allocations to be linear for now, since ARC++
doesn't properly pass modifiers to ChromeOS.

BUG=822346
TEST=test_that graphics_Gbm

Change-Id: I840c30d22355d26816df718b49717407e2e4620f
Reviewed-on: https://chromium-review.googlesource.com/996648
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Kristian H. Kristensen <hoegsberg@chromium.org>
Reviewed-by: Kristian H. Kristensen <hoegsberg@chromium.org>

diff --git a/cros_gralloc/cros_gralloc_driver.cc b/cros_gralloc/cros_gralloc_driver.cc
index a68023e..31282bc 100644 (file)
--- a/cros_gralloc/cros_gralloc_driver.cc
+++ b/cros_gralloc/cros_gralloc_driver.cc
@@ -91,13 +91,23 @@ int32_t cros_gralloc_driver::allocate(const struct cros_gralloc_buffer_descripto
        size_t num_planes;
        uint32_t resolved_format;
        uint32_t bytes_per_pixel;
+       uint64_t use_flags;
 
        struct bo *bo;
        struct cros_gralloc_handle *hnd;
 
        resolved_format = drv_resolve_format(drv_, descriptor->drm_format, descriptor->use_flags);
+       use_flags = descriptor->use_flags;
+       /*
+        * TODO(b/79682290): ARC++ assumes NV12 is always linear and doesn't
+        * send modifiers across Wayland protocol, so we or in the
+        * BO_USE_LINEAR flag here. We need to fix ARC++ to allocate and work
+        * with tiled buffers.
+        */
+       if (resolved_format == DRM_FORMAT_NV12)
+               use_flags |= BO_USE_LINEAR;
        bo = drv_bo_create(drv_, descriptor->width, descriptor->height, resolved_format,
-                          descriptor->use_flags);
+                          use_flags);
        if (!bo) {
                drv_log("Failed to create bo.\n");
                return -ENOMEM;

diff --git a/drv.h b/drv.h
index 9ca77d3..d27e845 100644 (file)
--- a/drv.h
+++ b/drv.h
@@ -37,6 +37,8 @@ extern "C" {
 #define BO_USE_CAMERA_READ             (1ull << 14)
 #define BO_USE_RENDERSCRIPT            (1ull << 16)
 #define BO_USE_TEXTURE                 (1ull << 17)
+#define BO_USE_HW_VIDEO_DECODER                (1ull << 18)
+
 
 /* Map flags */
 #define BO_MAP_NONE 0

diff --git a/gbm.h b/gbm.h
index da993c2..ce05ce3 100644 (file)
--- a/gbm.h
+++ b/gbm.h
@@ -265,6 +265,10 @@ enum gbm_bo_flags {
    GBM_BO_USE_SW_READ_RARELY = (1 << 10),
    GBM_BO_USE_SW_WRITE_OFTEN = (1 << 11),
    GBM_BO_USE_SW_WRITE_RARELY = (1 << 12),
+   /**
+    * The buffer will be written by a video decode accelerator.
+    */
+   GBM_BO_USE_HW_VIDEO_DECODER = (1 << 13),
 };
 
 int

diff --git a/gbm_helpers.c b/gbm_helpers.c
index 2683669..81d1680 100644 (file)
--- a/gbm_helpers.c
+++ b/gbm_helpers.c
@@ -40,6 +40,8 @@ uint64_t gbm_convert_usage(uint32_t usage)
                use_flags |= BO_USE_SW_WRITE_OFTEN;
        if (usage & GBM_BO_USE_SW_WRITE_RARELY)
                use_flags |= BO_USE_SW_WRITE_RARELY;
+       if (usage & GBM_BO_USE_HW_VIDEO_DECODER)
+               use_flags |= BO_USE_HW_VIDEO_DECODER;
 
        return use_flags;
 }

diff --git a/i915.c b/i915.c
index 8e1871a..6df6dcc 100644 (file)
--- a/i915.c
+++ b/i915.c
@@ -101,6 +101,10 @@ static int i915_add_kms_item(struct driver *drv, const struct kms_item *item)
                        combo->use_flags |= item->use_flags & ~BO_USE_CURSOR;
                }
 
+               /* If we can scanout NV12, we support all tiling modes. */
+               if (item->format == DRM_FORMAT_NV12)
+                       combo->use_flags |= item->use_flags;
+
                if (combo->metadata.modifier == item->modifier)
                        combo->use_flags |= item->use_flags;
        }
@@ -178,6 +182,11 @@ static int i915_add_combinations(struct driver *drv)
                             ARRAY_SIZE(tileable_texture_source_formats), &metadata,
                             texture_use_flags);
 
+       /* Support y-tiled NV12 for libva */
+       const uint32_t nv12_format = DRM_FORMAT_NV12;
+       drv_add_combinations(drv, &nv12_format, 1, &metadata,
+                            BO_USE_TEXTURE | BO_USE_HW_VIDEO_DECODER);
+
        kms_items = drv_query_kms(drv);
        if (!kms_items)
                return 0;