drm/msm: add helper to allocate stolen fb
We'll later want to re-use this for state-readback when bootloader
enables display, so that we can create an fb for the initial
plane->state->fb.
Signed-off-by: Rob Clark <robdclark@gmail.com>
diff --git a/drivers/gpu/drm/msm/msm_fb.c b/drivers/gpu/drm/msm/msm_fb.c
index 6ecb7b1..c87dd3e 100644
--- a/drivers/gpu/drm/msm/msm_fb.c
+++ b/drivers/gpu/drm/msm/msm_fb.c
@@ -20,6 +20,7 @@
#include "msm_drv.h"
#include "msm_kms.h"
+#include "msm_gem.h"
struct msm_framebuffer {
struct drm_framebuffer base;
@@ -237,3 +238,43 @@ struct drm_framebuffer *msm_framebuffer_init(struct drm_device *dev,
return ERR_PTR(ret);
}
+
+struct drm_framebuffer *
+msm_alloc_stolen_fb(struct drm_device *dev, int w, int h, int p, uint32_t format)
+{
+ struct drm_mode_fb_cmd2 mode_cmd = {
+ .pixel_format = format,
+ .width = w,
+ .height = h,
+ .pitches = { p },
+ };
+ struct drm_gem_object *bo;
+ struct drm_framebuffer *fb;
+ int size;
+
+ /* allocate backing bo */
+ size = mode_cmd.pitches[0] * mode_cmd.height;
+ DBG("allocating %d bytes for fb %d", size, dev->primary->index);
+ bo = msm_gem_new(dev, size, MSM_BO_SCANOUT | MSM_BO_WC | MSM_BO_STOLEN);
+ if (IS_ERR(bo)) {
+ dev_warn(dev->dev, "could not allocate stolen bo\n");
+ /* try regular bo: */
+ bo = msm_gem_new(dev, size, MSM_BO_SCANOUT | MSM_BO_WC);
+ }
+ if (IS_ERR(bo)) {
+ dev_err(dev->dev, "failed to allocate buffer object\n");
+ return ERR_CAST(bo);
+ }
+
+ fb = msm_framebuffer_init(dev, &mode_cmd, &bo);
+ if (IS_ERR(fb)) {
+ dev_err(dev->dev, "failed to allocate fb\n");
+ /* note: if fb creation failed, we can't rely on fb destroy
+ * to unref the bo:
+ */
+ drm_gem_object_unreference_unlocked(bo);
+ return ERR_CAST(fb);
+ }
+
+ return fb;
+}