[WIP] gallium/va: add termux-va bridge for hardware VA-API decode & encode

.github/workflows/build-check.yml

@@ -64,7 +64,10 @@ jobs:
             --prefix=/usr \
             -Dplatforms=x11,wayland \
             -Dgallium-drivers=freedreno,zink,virgl,llvmpipe \
-            -Dgallium-va=disabled \
+            -Dgallium-va=enabled \
+            -Dtermux-va-bridge=enabled \
+            -Dtermux-va-wayland-shim=enabled \
+            -Dvideo-codecs=all \
             -Dgallium-mediafoundation=disabled \
             -Dvulkan-drivers=freedreno \
             -Dvulkan-layers= \
@@ -165,7 +168,10 @@ jobs:
             --prefix=/usr \
             -Dplatforms=x11,wayland \
             -Dgallium-drivers=freedreno,zink,virgl,llvmpipe \
-            -Dgallium-va=disabled \
+            -Dgallium-va=enabled \
+            -Dtermux-va-bridge=enabled \
+            -Dtermux-va-wayland-shim=enabled \
+            -Dvideo-codecs=all \
             -Dgallium-mediafoundation=disabled \
             -Dvulkan-drivers=freedreno \
             -Dvulkan-layers= \
@@ -271,7 +277,10 @@ jobs:
             --prefix=/usr \
             -Dplatforms=x11,wayland \
             -Dgallium-drivers=freedreno,zink,virgl,llvmpipe \
-            -Dgallium-va=disabled \
+            -Dgallium-va=enabled \
+            -Dtermux-va-bridge=enabled \
+            -Dtermux-va-wayland-shim=enabled \
+            -Dvideo-codecs=all \
             -Dgallium-mediafoundation=disabled \
             -Dvulkan-drivers=freedreno \
             -Dvulkan-layers= \
@@ -375,7 +384,10 @@ jobs:
             --prefix=/usr \
             -Dplatforms=x11,wayland \
             -Dgallium-drivers=freedreno,zink,virgl,llvmpipe \
-            -Dgallium-va=disabled \
+            -Dgallium-va=enabled \
+            -Dtermux-va-bridge=enabled \
+            -Dtermux-va-wayland-shim=enabled \
+            -Dvideo-codecs=all \
             -Dgallium-mediafoundation=disabled \
             -Dvulkan-drivers=freedreno \
             -Dvulkan-layers= \
@@ -494,7 +506,10 @@ jobs:
             --prefix=/usr \
             -Dplatforms=x11,wayland \
             -Dgallium-drivers=freedreno,zink,virgl,llvmpipe \
-            -Dgallium-va=disabled \
+            -Dgallium-va=enabled \
+            -Dtermux-va-bridge=enabled \
+            -Dtermux-va-wayland-shim=enabled \
+            -Dvideo-codecs=all \
             -Dgallium-mediafoundation=disabled \
             -Dvulkan-drivers=freedreno \
             -Dvulkan-layers= \
@@ -598,7 +613,10 @@ jobs:
             --prefix=/usr \
             -Dplatforms=x11,wayland \
             -Dgallium-drivers=freedreno,zink,virgl,llvmpipe \
-            -Dgallium-va=disabled \
+            -Dgallium-va=enabled \
+            -Dtermux-va-bridge=enabled \
+            -Dtermux-va-wayland-shim=enabled \
+            -Dvideo-codecs=all \
             -Dgallium-mediafoundation=disabled \
             -Dvulkan-drivers=freedreno \
             -Dvulkan-layers= \
@@ -702,7 +720,10 @@ jobs:
             --prefix=/usr \
             -Dplatforms=x11,wayland \
             -Dgallium-drivers=freedreno,zink,virgl,llvmpipe \
-            -Dgallium-va=disabled \
+            -Dgallium-va=enabled \
+            -Dtermux-va-bridge=enabled \
+            -Dtermux-va-wayland-shim=enabled \
+            -Dvideo-codecs=all \
             -Dgallium-mediafoundation=disabled \
             -Dvulkan-drivers=freedreno \
             -Dvulkan-layers= \
@@ -775,6 +796,7 @@ jobs:
             python3-Mako python3-packaging python3-yaml python3-ply \
             libffi-devel \
             libzstd-devel \
+            libva-devel \
             glslang
 
       - name: Cache ccache
@@ -818,7 +840,10 @@ jobs:
             --prefix=/usr \
             -Dplatforms=x11,wayland \
             -Dgallium-drivers=freedreno,zink,virgl,llvmpipe \
-            -Dgallium-va=disabled \
+            -Dgallium-va=enabled \
+            -Dtermux-va-bridge=enabled \
+            -Dtermux-va-wayland-shim=enabled \
+            -Dvideo-codecs=all \
             -Dgallium-mediafoundation=disabled \
             -Dvulkan-drivers=freedreno \
             -Dvulkan-layers= \
@@ -923,7 +948,10 @@ jobs:
                 --prefix=/usr \
                 -Dplatforms=x11,wayland \
                 -Dgallium-drivers=freedreno,zink,virgl,llvmpipe \
-                -Dgallium-va=disabled \
+                -Dgallium-va=enabled \
+                -Dtermux-va-bridge=enabled \
+                -Dtermux-va-wayland-shim=enabled \
+                -Dvideo-codecs=all \
                 -Dgallium-mediafoundation=disabled \
                 -Dvulkan-drivers=freedreno \
                 -Dvulkan-layers= \

docs/envvars.rst

@@ -1404,6 +1404,108 @@ VA-API environment variables
 
    enable MPEG4 for VA-API, disabled by default.
 
+termux-va bridge environment variables
+--------------------------------------
+
+The termux-va bridge forwards VA-API video decoding over a Unix socket to
+the termux-va daemon running in Termux (Android MediaCodec hardware
+decode).  See :doc:`termux-va`.
+
+.. envvar:: TERMUX_VA_BRIDGE
+
+   ``1``/``true`` forces the bridge on, ``0``/``false`` forces it off.
+   When unset, the bridge activates automatically if ``TERMUX_VA_SOCKET``
+   or ``TERMUX_VA_SOCKET_DIR`` is set, or if the default endpoint exists
+   as a socket.
+
+.. envvar:: TERMUX_VA_SOCKET
+
+   Full path of the daemon's Unix socket file, overriding the default
+   ``/tmp/termux-va/termux-va.sock`` (the container-side view of the
+   Termux ``$TMPDIR/termux-va/`` shared-tmp directory).
+
+.. envvar:: TERMUX_VA_SOCKET_DIR
+
+   Directory containing the socket; ``termux-va.sock`` is appended.
+   Takes effect when ``TERMUX_VA_SOCKET`` is unset.  The same two
+   variables are understood by the daemon itself, so one setting covers
+   both ends.
+
+.. envvar:: TERMUX_VA_GPU_BACKEND
+
+   selects how the bridge creates the underlying screen that hosts the
+   decode surfaces:
+
+   - ``auto`` (default): try the stock loader and fall back to llvmpipe.  The KGSL alias is not attempted automatically.
+   - ``kgsl``: force the KGSL Freedreno alias.  GPU submission uses
+     ``/dev/kgsl-3d0`` while the handed fd remains the control/identity fd.
+     EGL and GLX loader selection follows this value, so
+     ``MESA_LOADER_DRIVER_OVERRIDE=kgsl`` and ``FD_FORCE_KGSL=1`` are not
+     required separately.
+   - ``drm``: use stock loader selection only.
+   - ``sw``: use llvmpipe only; no GPU is needed for the CPU frame-copy paths.
+
+.. envvar:: TERMUX_VA_DISABLE_AVC
+
+   set to ``1``, ``true`` or ``on`` to hide the H.264/AVC profiles from
+   libva.  ``TERMUX_VA_DISABLE_H264`` is accepted as a compatibility alias.
+
+.. envvar:: TERMUX_VA_DISABLE_HEVC
+
+   set to ``1``, ``true`` or ``on`` to hide the HEVC Main profile from libva.
+
+.. envvar:: TERMUX_VA_DISABLE_VP9
+
+   set to ``1``, ``true`` or ``on`` to hide the VP9 Profile 0 profile from
+   libva.
+
+.. envvar:: TERMUX_VA_DISABLE_AV1
+
+   set to ``1``, ``true`` or ``on`` to hide the AV1 Main profile from libva.
+   This is useful when Android exposes only a software MediaCodec component
+   for AV1, so applications can use their native software decoder instead.
+
+.. envvar:: DMD_WANT_SHM
+
+   set to ``0`` to disable the memfd shared-memory frame transport
+   (zero-copy) and always receive frames inline on the socket.  The
+   ``DMD_`` prefix is kept for compatibility with the upstream protocol
+   tooling.
+
+.. envvar:: TERMUX_VA_PIPELINE_DEPTH
+
+   sets the bridge's normal pending-picture depth to a value from 2 to 32
+   (default 6).
+   When shared-memory transport is enabled, the value is clamped to the
+   daemon's ``SHM_SLOTS`` limit.
+
+.. envvar:: DMD_VA_CPU_COPY
+
+   controls how staged frames are copied into bridge surfaces.  On the KGSL
+   backend CPU-mapped writes are enabled by default to make the cache handoff
+   to a separate Vulkan/KGSL importer explicit.  Set to ``0``, ``false`` or
+   ``off`` to retain the asynchronous Gallium ``texture_subdata`` path; set
+   to any other non-empty value to force CPU copies.
+
+.. envvar:: DMD_VA_CONTIGUOUS_DMABUF
+
+   controls the NV12 surface layout exported to consumers.  Set to ``1``,
+   ``true`` or ``on`` to place both planes in one dma-buf, or to ``0`` (or any
+   other value) to retain separate plane objects.  When unset, the bridge
+   automatically selects the single-object layout for a KGSL-only container
+   that has no DRM render node; this is required by Chromium's current native
+   pixmap importer.  ``TERMUX_VA_CONTIGUOUS_DMABUF`` is an alias.
+
+.. envvar:: DMD_VA_LOG
+
+   set to ``1`` to enable the bridge's daemon-client logging on stderr.
+
+.. envvar:: LIBVA_DRIVER_NAME
+
+   set to ``termuxva`` to make libva load the bridge through the
+   ``termuxva_drv_video.so`` megadriver symlink (recommended; automatic
+   driver discovery does not know the bridge).
+
 VC4 driver environment variables
 --------------------------------
 

docs/index.rst

@@ -121,6 +121,7 @@ Linux, FreeBSD, and other operating systems.
    isaspec
    rusticl
    android
+   termux-va
    macos
    Linux Kernel Drivers <https://www.kernel.org/doc/html/latest/gpu/>