feat: add Mesa EGL hardware GPU probe with virgl support

P5: Enable PRIME export for GBM dumb buffers so virgl can import scanout\nbuffers via fd-to-handle.

P6: Add redox_probe_device_hw() that opens /scheme/drm/card0, resolves the\nDRI driver via PCI ID lookup (loader_get_driver_for_fd), and initializes the\nhardware path through dri2_load_driver_dri3 with __DRIimageLoaderExtension.\nIncludes fprintf(stderr) debug logging tagged [REDOX-EGL] for tracing the\nHW init sequence. Falls back to software rendering if HW probe fails.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

local/patches/mesa/P5-gbm-dumb-prime-export.patch

@@ -0,0 +1,32 @@
+diff --git a/src/gbm/backends/dri/gbm_dri.c b/src/gbm/backends/dri/gbm_dri.c
+index 91fcc1fd2..af26e20d6 100644
+--- a/src/gbm/backends/dri/gbm_dri.c
++++ b/src/gbm/backends/dri/gbm_dri.c
+@@ -578,8 +578,11 @@ gbm_dri_bo_get_fd(struct gbm_bo *_bo)
+    struct gbm_dri_bo *bo = gbm_dri_bo(_bo);
+    int fd;
+ 
+-   if (bo->image == NULL)
+-      return -1;
++   if (bo->image == NULL) {
++      if (drmPrimeHandleToFD(dri->base.v0.fd, bo->handle, DRM_CLOEXEC | DRM_RDWR, &fd) != 0)
++         return -1;
++      return fd;
++   }
+ 
+    if (!dri->image->queryImage(bo->image, __DRI_IMAGE_ATTRIB_FD, &fd))
+       return -1;
+@@ -663,8 +666,11 @@ gbm_dri_bo_get_plane_fd(struct gbm_bo *_bo, int plane)
+ 
+    /* dumb BOs can only utilize non-planar formats */
+    if (!bo->image) {
+-      errno = EINVAL;
+-      return -1;
++      if (plane != 0) {
++         errno = EINVAL;
++         return -1;
++      }
++      return gbm_dri_bo_get_fd(_bo);
+    }
+ 
+    if (plane >= get_number_planes(dri, bo->image)) {

local/patches/mesa/P6-platform-redox-gpu-probe.patch

@@ -0,0 +1,240 @@
+diff --git a/src/egl/drivers/dri2/platform_redox.c b/src/egl/drivers/dri2/platform_redox.c
+index d6ceb1107..03d8e4c21 100644
+--- a/src/egl/drivers/dri2/platform_redox.c
++++ b/src/egl/drivers/dri2/platform_redox.c
+@@ -62,10 +62,46 @@ redox_free_images(struct dri2_egl_surface *dri2_surf)
+        dri2_surf->front = NULL;
+     }
+ 
++    if (dri2_surf->dri_image_back) {
++       dri2_dpy->image->destroyImage(dri2_surf->dri_image_back);
++       dri2_surf->dri_image_back = NULL;
++    }
++
+     free(dri2_surf->swrast_device_buffer);
+     dri2_surf->swrast_device_buffer = NULL;
+ }
+ 
++static int
++redox_image_get_buffers(__DRIdrawable *driDrawable, unsigned int format,
++                        uint32_t *stamp, void *loaderPrivate,
++                        uint32_t buffer_mask,
++                        struct __DRIimageList *buffers)
++{
++    struct dri2_egl_surface *dri2_surf = loaderPrivate;
++    struct dri2_egl_display *dri2_dpy =
++       dri2_egl_display(dri2_surf->base.Resource.Display);
++
++    buffers->image_mask = 0;
++    buffers->front = NULL;
++    buffers->back = NULL;
++
++    if (buffer_mask & __DRI_IMAGE_BUFFER_FRONT) {
++       if (!dri2_surf->front)
++          dri2_surf->front = redox_alloc_image(dri2_dpy, dri2_surf);
++       buffers->image_mask |= __DRI_IMAGE_BUFFER_FRONT;
++       buffers->front = dri2_surf->front;
++    }
++
++    if (buffer_mask & __DRI_IMAGE_BUFFER_BACK) {
++       if (!dri2_surf->dri_image_back)
++          dri2_surf->dri_image_back = redox_alloc_image(dri2_dpy, dri2_surf);
++       buffers->image_mask |= __DRI_IMAGE_BUFFER_BACK;
++       buffers->back = dri2_surf->dri_image_back;
++    }
++
++    return 1;
++}
++
+ static EGLBoolean
+ redox_swap_interval(_EGLDisplay *disp, _EGLSurface *surf, EGLint interval)
+ {
+@@ -220,6 +256,10 @@ dri2_redox_create_window_surface(_EGLDisplay *disp, _EGLConfig *conf,
+        goto cleanup_surface;
+     }
+ 
++    dri2_surf->visual = dri2_image_format_for_pbuffer_config(dri2_dpy, config);
++    if (dri2_surf->visual == __DRI_IMAGE_FORMAT_NONE)
++       goto cleanup_surface;
++
+     if (!dri2_create_drawable(dri2_dpy, config, dri2_surf, dri2_surf)) {
+         goto cleanup_surface;
+     }
+@@ -366,6 +406,27 @@ static const __DRIkopperLoaderExtension kopper_loader_extension = {
+     .SetSurfaceCreateInfo = NULL,
+ };
+ 
++static void
++redox_hw_flush_front_buffer(__DRIdrawable *driDrawable, void *loaderPrivate)
++{
++}
++
++static const __DRIimageLoaderExtension redox_image_loader_extension = {
++    .base = {__DRI_IMAGE_LOADER, 2},
++    .getBuffers = redox_image_get_buffers,
++    .flushFrontBuffer = redox_hw_flush_front_buffer,
++    .getCapability = redox_get_capability,
++};
++
++static const __DRIextension *redox_hw_loader_extensions[] = {
++    &redox_image_loader_extension.base,
++    &image_lookup_extension.base,
++    &use_invalidate.base,
++    &background_callable_extension.base,
++    &kopper_loader_extension.base,
++    NULL,
++};
++
+ static const __DRIswrastLoaderExtension swrast_loader_extension = {
+     .base = {__DRI_SWRAST_LOADER, 1},
+     .getDrawableInfo = redox_swrast_get_drawable_info,
+@@ -381,6 +442,92 @@ static const __DRIextension *redox_swrast_loader_extensions[] = {
+     NULL,
+ };
+ 
++static bool
++redox_probe_device_hw(_EGLDisplay *disp)
++{
++    struct dri2_egl_display *dri2_dpy = dri2_egl_display(disp);
++    struct _egl_device *device;
++    int fd = -1;
++
++    /* Try to open a DRM device on Redox first, then the conventional path. */
++    const char *drm_paths[] = {
++        "/scheme/drm/card0",
++        "/dev/dri/card0",
++        NULL,
++    };
++
++    fprintf(stderr, "[REDOX-EGL] redox_probe_device_hw: starting\n");
++
++    for (int i = 0; drm_paths[i]; i++) {
++        fd = open(drm_paths[i], O_RDWR | O_CLOEXEC);
++        fprintf(stderr, "[REDOX-EGL] open(%s) = %d\n", drm_paths[i], fd);
++        if (fd >= 0)
++            break;
++    }
++
++    if (fd < 0) {
++        fprintf(stderr, "[REDOX-EGL] no DRM device found\n");
++        return false;
++    }
++
++    /* Resolve the DRI driver from the DRM fd via PCI ID lookup. */
++    char *driver_name = loader_get_driver_for_fd(fd);
++    fprintf(stderr, "[REDOX-EGL] loader_get_driver_for_fd returned: %s\n",
++            driver_name ? driver_name : "(null)");
++    if (!driver_name) {
++        close(fd);
++        return false;
++    }
++
++    if (strcmp(driver_name, "swrast") == 0 ||
++        strcmp(driver_name, "kms_swrast") == 0) {
++        fprintf(stderr, "[REDOX-EGL] driver is swrast/kms_swrast, skipping HW path\n");
++        free(driver_name);
++        close(fd);
++        return false;
++    }
++
++    dri2_dpy->fd_render_gpu = fd;
++    dri2_dpy->driver_name = driver_name;
++
++    device = _eglFindDevice(fd, false);
++    fprintf(stderr, "[REDOX-EGL] _eglFindDevice returned: %p\n", (void *)device);
++    if (!device) {
++        free(driver_name);
++        close(fd);
++        dri2_dpy->driver_name = NULL;
++        dri2_dpy->fd_render_gpu = -1;
++        return false;
++    }
++
++    if (_eglHasAttrib(disp, EGL_DEVICE_EXT) && disp->Device != device) {
++        fprintf(stderr, "[REDOX-EGL] EGL_DEVICE_EXT mismatch\n");
++        free(driver_name);
++        close(fd);
++        dri2_dpy->driver_name = NULL;
++        dri2_dpy->fd_render_gpu = -1;
++        return false;
++    }
++    disp->Device = device;
++
++    /* Hardware drivers expose the DRI3/image entrypoints we need here. */
++    fprintf(stderr, "[REDOX-EGL] calling dri2_load_driver_dri3 (driver=%s)...\n", driver_name);
++    if (!dri2_load_driver_dri3(disp)) {
++        fprintf(stderr, "[REDOX-EGL] dri2_load_driver_dri3 FAILED\n");
++        free(driver_name);
++        close(fd);
++        dri2_dpy->driver_name = NULL;
++        dri2_dpy->fd_render_gpu = -1;
++        return false;
++    }
++    fprintf(stderr, "[REDOX-EGL] dri2_load_driver_dri3 succeeded\n");
++
++    dri2_dpy->loader_extensions = redox_hw_loader_extensions;
++
++    fprintf(stderr, "[REDOX-EGL] redox_probe_device_hw: SUCCESS (driver=%s)\n", driver_name);
++    return true;
++}
++
+ static bool
+ redox_probe_device_sw(_EGLDisplay *disp)
+ {
+@@ -488,6 +635,8 @@ dri2_initialize_redox(_EGLDisplay *disp)
+     bool driver_loaded = false;
+     struct dri2_egl_display *dri2_dpy = dri2_display_create();
+ 
++    fprintf(stderr, "[REDOX-EGL] dri2_initialize_redox: starting\n");
++
+     if (!dri2_dpy) {
+         err = "dri2_display_create failed";
+         goto cleanup;
+@@ -495,7 +644,12 @@ dri2_initialize_redox(_EGLDisplay *disp)
+ 
+     disp->DriverData = (void *)dri2_dpy;
+ 
+-      driver_loaded = redox_probe_device_sw(disp);
++    /* Try hardware GPU first (virgl, amdgpu, etc.). */
++    driver_loaded = redox_probe_device_hw(disp);
++    fprintf(stderr, "[REDOX-EGL] HW probe: %s\n", driver_loaded ? "SUCCESS" : "FAILED");
++    /* Fall back to software rendering (llvmpipe/softpipe). */
++    if (!driver_loaded)
++       driver_loaded = redox_probe_device_sw(disp);
+ 
+     if (!driver_loaded) {
+        err = "DRI2: failed to load driver";
+@@ -503,16 +657,21 @@ dri2_initialize_redox(_EGLDisplay *disp)
+     }
+ 
+     dri2_dpy->fd_display_gpu = dri2_dpy->fd_render_gpu;
++    fprintf(stderr, "[REDOX-EGL] calling dri2_create_screen...\n");
+ 
+     if (!dri2_create_screen(disp)) {
+        err = "DRI2: failed to create screen";
++       fprintf(stderr, "[REDOX-EGL] dri2_create_screen FAILED\n");
+        goto cleanup;
+     }
++    fprintf(stderr, "[REDOX-EGL] dri2_create_screen succeeded\n");
+ 
+     if (!dri2_setup_extensions(disp)) {
+        err = "DRI2: failed to find required DRI extensions";
++       fprintf(stderr, "[REDOX-EGL] dri2_setup_extensions FAILED\n");
+        goto cleanup;
+     }
++    fprintf(stderr, "[REDOX-EGL] dri2_setup_extensions succeeded\n");
+ 
+     dri2_setup_screen(disp);
+ 
+@@ -532,9 +691,11 @@ dri2_initialize_redox(_EGLDisplay *disp)
+ 
+     dri2_dpy->vtbl = &dri2_redox_display_vtbl;
+ 
++    fprintf(stderr, "[REDOX-EGL] dri2_initialize_redox: COMPLETE\n");
+     return EGL_TRUE;
+ 
+ cleanup:
++    fprintf(stderr, "[REDOX-EGL] dri2_initialize_redox: FAILED: %s\n", err);
+     dri2_display_destroy(disp);
+     return _eglError(EGL_NOT_INITIALIZED, err);
+ }

recipes/libs/mesa/recipe.toml

@@ -3,7 +3,7 @@ git = "https://gitlab.redox-os.org/redox-os/mesa.git"
 upstream = "https://gitlab.freedesktop.org/mesa/mesa"
 branch = "redox-24.0"
 shallow_clone = true
-patches = ["../../../local/patches/mesa/P4-virgl-redox-disk-cache.patch"]
+patches = ["../../../local/patches/mesa/P4-virgl-redox-disk-cache.patch", "../../../local/patches/mesa/P5-gbm-dumb-prime-export.patch", "../../../local/patches/mesa/P6-platform-redox-gpu-probe.patch"]
 [build]
 template = "custom"
 dependencies = [