"Overallocation of the fbdev buffer (%) [default="
__MODULE_STRING(CONFIG_DRM_FBDEV_OVERALLOC) "]");
+/*
+ * In order to keep user-space compatibility, we want in certain use-cases
+ * to keep leaking the fbdev physical address to the user-space program
+ * handling the fbdev buffer.
+ * This is a bad habit essentially kept into closed source opengl driver
+ * that should really be moved into open-source upstream projects instead
+ * of using legacy physical addresses in user space to communicate with
+ * other out-of-tree kernel modules.
+ *
+ * This module_param *should* be removed as soon as possible and be
+ * considered as a broken and legacy behaviour from a modern fbdev device.
+ */
+#if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
+static bool drm_leak_fbdev_smem = false;
+module_param_unsafe(drm_leak_fbdev_smem, bool, 0600);
+MODULE_PARM_DESC(fbdev_emulation,
+ "Allow unsafe leaking fbdev physical smem address [default=false]");
+#endif
+
static LIST_HEAD(kernel_fb_helper_list);
static DEFINE_MUTEX(kernel_fb_helper_lock);
info = fb_helper->fbdev;
info->var.pixclock = 0;
+ /* Shamelessly allow physical address leaking to userspace */
+#if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
+ if (!drm_leak_fbdev_smem)
+#endif
+ /* don't leak any physical addresses to userspace */
+ info->flags |= FBINFO_HIDE_SMEM_START;
/* Need to drop locks to avoid recursive deadlock in
* register_framebuffer. This is ok because the only thing left to do is
* The caller must to provide a &drm_fb_helper_funcs->fb_probe callback
* function.
*
- * See also: drm_fb_helper_initial_config()
+ * Use drm_fb_helper_fbdev_teardown() to destroy the fbdev.
+ *
+ * See also: drm_fb_helper_initial_config(), drm_fbdev_generic_setup().
*
* Returns:
* Zero on success or negative error code on failure.
if (!max_conn_count)
max_conn_count = dev->mode_config.num_connector;
if (!max_conn_count) {
- DRM_DEV_ERROR(dev->dev, "No connectors\n");
+ DRM_DEV_ERROR(dev->dev, "fbdev: No connectors\n");
return -EINVAL;
}
ret = drm_fb_helper_init(dev, fb_helper, max_conn_count);
if (ret < 0) {
- DRM_DEV_ERROR(dev->dev, "Failed to initialize fbdev helper\n");
+ DRM_DEV_ERROR(dev->dev, "fbdev: Failed to initialize (ret=%d)\n", ret);
return ret;
}
ret = drm_fb_helper_single_add_all_connectors(fb_helper);
if (ret < 0) {
- DRM_DEV_ERROR(dev->dev, "Failed to add connectors\n");
+ DRM_DEV_ERROR(dev->dev, "fbdev: Failed to add connectors (ret=%d)\n", ret);
goto err_drm_fb_helper_fini;
}
ret = drm_fb_helper_initial_config(fb_helper, preferred_bpp);
if (ret < 0) {
- DRM_DEV_ERROR(dev->dev, "Failed to set fbdev configuration\n");
+ DRM_DEV_ERROR(dev->dev, "fbdev: Failed to set configuration (ret=%d)\n", ret);
goto err_drm_fb_helper_fini;
}
* @fb_helper: fbdev helper structure
* @sizes: describes fbdev size and scanout surface size
*
- * This function uses the client API to crate a framebuffer backed by a dumb buffer.
+ * This function uses the client API to create a framebuffer backed by a dumb buffer.
*
* The _sys_ versions are used for &fb_ops.fb_read, fb_write, fb_fillrect,
* fb_copyarea, fb_imageblit.
fbi->screen_size = fb->height * fb->pitches[0];
fbi->fix.smem_len = fbi->screen_size;
fbi->screen_buffer = buffer->vaddr;
+ /* Shamelessly leak the physical address to user-space */
+#if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
+ if (drm_leak_fbdev_smem && fbi->fix.smem_start == 0)
+ fbi->fix.smem_start =
+ page_to_phys(virt_to_page(fbi->screen_buffer));
+#endif
strcpy(fbi->fix.id, "DRM emulated");
drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->format->depth);
if (dev->fb_helper)
return drm_fb_helper_hotplug_event(dev->fb_helper);
- if (!dev->mode_config.num_connector)
+ if (!dev->mode_config.num_connector) {
+ DRM_DEV_DEBUG(dev->dev, "No connectors found, will not create framebuffer!\n");
return 0;
+ }
ret = drm_fb_helper_fbdev_setup(dev, fb_helper, &drm_fb_helper_generic_funcs,
fb_helper->preferred_bpp, 0);
};
/**
- * drm_fb_helper_generic_fbdev_setup() - Setup generic fbdev emulation
+ * drm_fbdev_generic_setup() - Setup generic fbdev emulation
* @dev: DRM device
* @preferred_bpp: Preferred bits per pixel for the device.
* @dev->mode_config.preferred_depth is used if this is zero.
*
* This function sets up generic fbdev emulation for drivers that supports
- * dumb buffers with a virtual address and that can be mmap'ed.
+ * dumb buffers with a virtual address and that can be mmap'ed. If the driver
+ * does not support these functions, it could use drm_fb_helper_fbdev_setup().
*
* Restore, hotplug events and teardown are all taken care of. Drivers that do
* suspend/resume need to call drm_fb_helper_set_suspend_unlocked() themselves.
* This function is safe to call even when there are no connectors present.
* Setup will be retried on the next hotplug event.
*
+ * The fbdev is destroyed by drm_dev_unregister().
+ *
* Returns:
* Zero on success or negative error code on failure.
*/
struct drm_fb_helper *fb_helper;
int ret;
+ WARN(dev->fb_helper, "fb_helper is already set!\n");
+
if (!drm_fbdev_emulation)
return 0;
ret = drm_client_init(dev, &fb_helper->client, "fbdev", &drm_fbdev_client_funcs);
if (ret) {
kfree(fb_helper);
+ DRM_DEV_ERROR(dev->dev, "Failed to register client: %d\n", ret);
return ret;
}
fb_helper->preferred_bpp = preferred_bpp;
- drm_fbdev_client_hotplug(&fb_helper->client);
+ ret = drm_fbdev_client_hotplug(&fb_helper->client);
+ if (ret)
+ DRM_DEV_DEBUG(dev->dev, "client hotplug ret=%d\n", ret);
return 0;
}
projects / platform / kernel / linux-starfive.git / blobdiff