feat: Mali Vulkan support through MaliBridge (#2027)

tools/linuxfs/desktop/droiddeck-desktop

@@ -114,8 +114,10 @@ fi
 if [ "$(cat /usr/share/droiddeck/kwin-compositor 2>/dev/null)" = opengl ]; then
   unset LIBGL_ALWAYS_SOFTWARE QT_QUICK_BACKEND
   export KWIN_COMPOSE=O2 MESA_LOADER_DRIVER_OVERRIDE=zink GALLIUM_DRIVER=zink LIBGL_KOPPER_DRI2=true
-  if [ -z "${KWIN_RENDER_NODES:-}" ] && [ -c /dev/dri/renderD0 ]; then
-    export KWIN_RENDER_NODES=/dev/dri/renderD0
+  if [ -z "${KWIN_RENDER_NODES:-}" ]; then
+    for node in /dev/dri/renderD0 /dev/dri/renderD307 /dev/dri/renderD*; do
+      if [ -c "$node" ]; then export KWIN_RENDER_NODES="$node"; break; fi
+    done
   fi
   mkdir -p /run/droiddeck/kwin
   printf '#!/bin/sh\nGALLIUM_THREAD=0 exec /usr/bin/kwin_wayland "$@"\n' > /run/droiddeck/kwin/kwin_wayland

tools/linuxfs/overlay/usr/local/bin/droiddeck-game-env

@@ -478,6 +478,14 @@ def apply_config(env, config, app_id, fixes=None):
     return result
 
 
+def bridge_feature_level(env):
+    if env.get("BL_VKBRIDGE") != "1" or env.get("VKD3D_FEATURE_LEVEL") not in ("12_1", "12_2"):
+        return None
+    was = env["VKD3D_FEATURE_LEVEL"]
+    env["VKD3D_FEATURE_LEVEL"] = "12_0"
+    return "Mali bridge: VKD3D_FEATURE_LEVEL %s capped at 12_0 (no ray tracing or mesh shaders)" % was
+
+
 GAME_DEBUG_CHANNELS = (
     "timestamp", "pid", "tid", "seh", "unwind", "threadname", "debugstr", "loaddll", "mscoree",
 )
@@ -974,6 +982,9 @@ def main():
         env["AUDIO_DIRECT_MIC"] = "0"
     env = directaudio_settings(env)
     env = vram_cap(env)
+    note = bridge_feature_level(env)
+    if note:
+        print("droiddeck-game-env: " + note, file=sys.stderr)
     env = force_ssbs(command, env)
     game_cores(env)
     cpu_topology(env, command)

tools/linuxfs/overlay/usr/local/bin/droiddeck-session

@@ -160,7 +160,7 @@ collect_steam_logs() {
     cp "$fex_state/status.json" "$fex_state/config/Config.json" "$BL_DEBUG_DIR/droiddeck-fex/" 2>/dev/null
   fi
 }
-trap 'collect_steam_logs 2>/dev/null || true' TERM INT HUP
+trap 'bl_stopping=1; collect_steam_logs 2>/dev/null || true' TERM INT HUP
 if [ -n "${BL_VK_DRIVER:-}" ]; then
   bl_icd_lib=$(sed -n 's/.*"library_path"[[:space:]]*:[[:space:]]*"\([^"]*\)".*/\1/p' "$BL_VK_DRIVER" 2>/dev/null | head -1)
   bl_icd_lib=$(printf '%s' "$bl_icd_lib" | sed 's|\\/|/|g')
@@ -177,6 +177,83 @@ if [ -n "${BL_VK_DRIVER:-}" ]; then
   fi
   unset bl_icd_lib
 fi
+bl_webhelper_layout() {
+  if [ -n "${BL_VKBRIDGE_WEBHELPER_ARGS:-}" ]; then
+    printf '%s\n' "$BL_VKBRIDGE_WEBHELPER_ARGS"
+  elif [ -z "${BL_VKBRIDGE_CEF_ANGLE:-}" ]; then
+    echo stock
+  elif [ "$BL_VKBRIDGE_CEF_ANGLE" = vulkan ] && [ "${BL_VKBRIDGE_CEF_VULKAN:-1}" != 0 ]; then
+    echo "--use-gl=angle --use-angle=vulkan +Vulkan +VulkanFromANGLE +DefaultANGLEVulkan"
+  else
+    echo "--use-gl=angle --use-angle=$BL_VKBRIDGE_CEF_ANGLE"
+  fi
+}
+bl_now_ms() {
+  if [ -n "${EPOCHREALTIME:-}" ]; then
+    local t=${EPOCHREALTIME/[.,]/}
+    echo $((10#$t / 1000))
+  else
+    date +%s%3N
+  fi
+}
+vkbridge_wait_socket() {
+  local sock=$1 limit=${2:-10000} start now waited
+  [ -n "$sock" ] || return 1
+  if [ -S "$sock" ]; then
+    echo "== vkbridge: server socket ready (waited 0 ms)"
+    return 0
+  fi
+  start=$(bl_now_ms)
+  while :; do
+    now=$(bl_now_ms)
+    waited=$((now - start))
+    if [ -S "$sock" ]; then
+      echo "== vkbridge: server socket ready (waited $waited ms; the server listens after its startup probe)"
+      return 0
+    fi
+    if [ -n "${bl_stopping:-}" ]; then
+      echo "== vkbridge: no server socket after $waited ms; the session is stopping"
+      return 1
+    fi
+    if [ "$waited" -ge "$limit" ]; then
+      echo "== vkbridge: no server socket after $waited ms (gave up at $limit ms)"
+      return 1
+    fi
+    sleep 0.05
+  done
+}
+if [ "${BL_VKBRIDGE:-0}" = 1 ]; then
+  bl_vkb_icd=/usr/local/share/vkbridge/droidbridge_icd.json
+  [ -z "${BL_INSIDE:-}" ] && vkbridge_wait_socket "${VKBRIDGE_SOCKET:-}" "${BL_VKBRIDGE_WAIT_MS:-10000}"
+  bl_vkb_missing=
+  [ -r "$bl_vkb_icd" ] || bl_vkb_missing="$bl_vkb_missing icd"
+  [ -r /usr/local/lib/vkbridge/libvulkan_droidbridge.so ] || bl_vkb_missing="$bl_vkb_missing library"
+  [ -S "${VKBRIDGE_SOCKET:-}" ] || bl_vkb_missing="$bl_vkb_missing socket"
+  if [ -z "$bl_vkb_missing" ]; then
+    export VK_DRIVER_FILES=$bl_vkb_icd VK_ICD_FILENAMES=$bl_vkb_icd
+    export VKBRIDGE_SOCKET VKBRIDGE_CLIENT_LOG
+    if [ -r /root/.vkbridge-env ]; then
+      while IFS='=' read -r _k _v; do
+        case "$_k" in VKBRIDGE_*|BL_VKBRIDGE_*) export "$_k=$_v" ;; esac
+      done < /root/.vkbridge-env
+      [ -z "${BL_INSIDE:-}" ] && echo "== vkbridge: development settings from /root/.vkbridge-env: $(cut -d= -f1 /root/.vkbridge-env | tr '\n' ' ')"
+    fi
+    export VKD3D_FEATURE_LEVEL=${VKD3D_FEATURE_LEVEL:-12_0}
+    unset TU_DEBUG
+    if [ -z "${BL_INSIDE:-}" ]; then
+      step "vkbridge self-test"
+      timeout 60 /usr/local/bin/droiddeck-vkbridge-smoke 2>&1 | sed 's/^/== vkbridge: /'
+      if command -v vulkaninfo >/dev/null 2>&1; then
+        timeout 30 vulkaninfo --summary 2>&1 | sed -n '/^Devices:/,$p' | head -40 | sed 's/^/== vulkaninfo: /'
+      fi
+    fi
+    echo "== vulkan driver: Mali bridge ($bl_vkb_icd, server at $VKBRIDGE_SOCKET)"
+  else
+    echo "== vulkan driver: Mali bridge requested but NOT usable (icd $bl_vkb_icd, socket ${VKBRIDGE_SOCKET:-unset}; missing:$bl_vkb_missing)"
+    [ -n "${BL_INSIDE:-}" ] || exit 69
+  fi
+  unset bl_vkb_icd bl_vkb_missing
+fi
 export GAMESCOPE_FORCE_VULKAN_REALTIME=${BL_GAMESCOPE_REALTIME:-0}
 
 start_agent() {
@@ -307,6 +384,13 @@ if [ -z "${BL_INSIDE:-}" ]; then
   if [ "$mode" = steam ] && [ "${BL_CURSOR_COMPOSITE:-0}" = 1 ]; then
     export gamescope_cursor_composite=2
   fi
+  # Through the Mali bridge, Steam's UI flickered while gamescope handed its layers to the phone's
+  # compositor as separate planes, for a reason not yet found; one composited image does not
+  # (Mali-G76 MC4: 145 footer flips in 6 s at rest, 0 composited).
+  if [ "$mode" = steam ] && [ "${BL_VKBRIDGE:-0}" = 1 ] && [ -z "${gamescope_composite_force:-}" ]; then
+    export gamescope_composite_force=1
+    echo "== gamescope: composites every frame (Mali bridge: the Steam UI flickers on separate planes)"
+  fi
   args=(--backend wayland --expose-wayland -f -W "$width" -H "$height" -w "$nested" -h "$nested_h")
   if [ "$nested" != "$width" ] || [ "$nested_h" != "$height" ]; then
     args+=(-S stretch)
@@ -1023,6 +1107,28 @@ case $mode in
       _bl_cef=(-cef-disable-gpu)
       _bl_ui=(-nobigpicture)
     fi
+    if [ "${BL_VKBRIDGE:-0}" = 1 ]; then
+      # On the GPU the Steam UI held about 400 MB through the bridge (Mali-G76 MC4, 3 GB of RAM); with
+      # a game loading beside it, Android's low-memory killer took the whole session down.
+      if [ -z "${BL_VKBRIDGE_CEF_GPU:-}" ]; then
+        _bl_mem_kb=$(awk '/^MemTotal:/ {print $2}' /proc/meminfo 2>/dev/null)
+        if [ "${_bl_mem_kb:-0}" -gt 0 ] && [ "$_bl_mem_kb" -lt 4194304 ]; then
+          BL_VKBRIDGE_CEF_GPU=0
+          echo "== steam: $((_bl_mem_kb / 1024)) MB of RAM: the browser UI draws in software to leave games the memory"
+        fi
+      fi
+      if [ "${BL_VKBRIDGE_CEF_GPU:-1}" = 0 ]; then
+        _bl_cef=(-cef-disable-gpu -cef-disable-gpu-compositing)
+        echo "== steam: browser UI in software (Mali bridge)"
+      elif [ "${_bl_cef[0]}" = -cef-force-gpu ]; then
+        _bl_cef=(-cef-force-gpu -cef-use-gl=angle -cef-use-angle="${BL_VKBRIDGE_CEF_ANGLE:-vulkan}")
+      fi
+      [ "${BL_VKBRIDGE_CEF_LOG:-0}" = 1 ] && _bl_cef+=(-cef-enable-logging=stderr -cef-v=1)
+      [ -n "${BL_VKBRIDGE_CEF_EXTRA:-}" ] && read -r -a _bl_cef_extra <<<"$BL_VKBRIDGE_CEF_EXTRA" && _bl_cef+=("${_bl_cef_extra[@]}")
+      BL_WEBHELPER_ARGS=$(bl_webhelper_layout)
+      export BL_WEBHELPER_ARGS
+      echo "== steam: web helper process layout: $BL_WEBHELPER_ARGS (Mali bridge)"
+    fi
     if [ "${BL_STEAM_UI:-}" != desktop ]; then
       if [ "$steam_x64" = 0 ] || [ "${BL_X64_DECK:-1}" != 0 ]; then
         _bl_ui+=(-steamdeck -steamos3)

tools/linuxfs/preload/drm.c

@@ -5,6 +5,7 @@
 #include <pthread.h>
 #include <stdint.h>
 #include <stdlib.h>
+#include <sys/file.h>
 #include <sys/ioctl.h>
 #include <sys/stat.h>
 #include <sys/syscall.h>
@@ -34,7 +35,8 @@ static int is_kgsl(int fd) {
   struct stat st;
   pthread_mutex_lock(&lock);
   if (kgsl_state == 0) {
-    kgsl_state = stat("/dev/kgsl-3d0", &st) == 0 ? 1 : -1;
+    const char *standin = getenv("BL_DRM_STANDIN");
+    kgsl_state = stat("/dev/kgsl-3d0", &st) == 0 || (standin && *standin && stat(standin, &st) == 0) ? 1 : -1;
     kgsl_dev = st.st_rdev;
   }
   pthread_mutex_unlock(&lock);
@@ -49,18 +51,42 @@ static void *real(const char *name) {
   return fn;
 }
 
+static int same_by_flock(int a, int b) {
+  struct stat sa, sb;
+  if (fstat(a, &sa) || fstat(b, &sb) || sa.st_dev != sb.st_dev || sa.st_ino != sb.st_ino ||
+      flock(a, LOCK_EX | LOCK_NB)) {
+    return 0;
+  }
+  int same = flock(b, LOCK_EX | LOCK_NB) == 0;
+  flock(a, LOCK_UN);
+  return same;
+}
+
 static int same_file_description(int a, int b) {
   if (a == b) {
     return 1;
   }
-#ifdef SYS_kcmp
   int saved_errno = errno;
-  long ret = syscall(SYS_kcmp, getpid(), getpid(), 0  , a, b);
-  errno = saved_errno;
-  return ret == 0;
-#else
-  return 0;
+  int ret = -1;
+#ifdef SYS_kcmp
+  static int kcmp_missing;
+  if (!kcmp_missing) {
+    long k = syscall(SYS_kcmp, getpid(), getpid(), 0, a, b);
+    if (k >= 0) {
+      ret = k == 0;
+    } else if (errno == ENOSYS || errno == EPERM) {
+      kcmp_missing = 1;
+    } else {
+      ret = 0;
+    }
+  }
 #endif
+  if (ret < 0) {
+    const char *standin = getenv("BL_DRM_STANDIN");
+    ret = standin && *standin ? same_by_flock(a, b) : 0;
+  }
+  errno = saved_errno;
+  return ret;
 }
 
 static int find_handle_locked(int fd, uint32_t handle) {