Probe the GPUs/kernel and select an appropriate accel method, fix #3

Only use vDRM on supported drivers, introduce Venus for others, and fall
back to software on kernels older than 6.13 due to missing PFNMAP support.

munix

@@ -56,8 +56,40 @@ if [ "$GPU" -eq 1 ]; then
     "--dev-bind" "/dev/dri" "/dev/dri"
     "--ro-bind" "$HOST_OPENGL_DRIVER" "/run/opengl-driver"
   )
+  GPU_MODE=venus
+  kernel_ver="$(uname -r)"
+  kernel_ver_arr=(${kernel_ver//./ })
+  kernel_major="${kernel_ver_arr:-0}"
+  kernel_ver_arr=("${kernel_ver_arr[@]:1}")
+  kernel_minor="${kernel_ver_arr:-0}"
+  if [[ "$kernel_major" -gt 6 || ("$kernel_major" -eq 6 && "$kernel_minor" -gt 12) ]]; then
+    for card in /dev/dri/card*; do
+      driver_link="/sys/class/drm/${card##*/}/device/driver"
+      if [ -L "$driver_link" ]; then
+        driver_mod="$(readlink "$driver_link")"
+        driver_name="${driver_mod##*/}"
+        case "$driver_name" in
+          amdgpu|msm) # TODO: i915
+            echo "munix: ${card##*/} gpu driver is '$driver_name', using vdrm" >&2;
+            GPU_MODE=drm
+            break;;
+          *) echo "munix: ${card##*/} gpu driver is '$driver_name', using venus unless more gpus are found" >&2;;
+        esac
+      else
+        echo "munix: ${card##*/} has no gpu driver" >&2;
+      fi
+    done
+  else
+    echo "munix: kernel version '$kernel_ver' is older than 6.13, not using gpu due to missing support" >&2;
+    GPU_MODE=software
+  fi
+  MUVM_ARGS+=("--gpu-mode=$GPU_MODE")
+  if [ "$GPU_MODE" = "venus" ]; then
+    MUVM_ARGS+=("-e" "MESA_LOADER_DRIVER_OVERRIDE=zink")
+  fi
 else
   BWRAP_ARGS+=("--dir" "/dev/dri")
+  MUVM_ARGS+=("--gpu-mode=software")
 fi
 
 if [ "$WAYLAND" -eq 1 ]; then

muvm

@@ -1 +1 @@
-Subproject commit 70badbc44d421c49f82130321e35b949f8b4ed14
+Subproject commit 53d416fb3f96b04a5bd3dd40f94fa4d8fbf1d7f1