[PATCH 5/7] drm/udl: Convert to drm_atomic_helper_dirtyfb()

[Daniel Vetter]

On Fri, Nov 29, 2019 at 06:04:02PM +0000, Emil Velikov wrote:
> Hi Thomas,
> 
> On Tue, 26 Nov 2019 at 13:47, Thomas Zimmermann <tzimmermann at suse.de> wrote:
> >
> > The infrastruture for atomic modesetting allows us to use the generic
> > code for dirty-FB and damage handling. Switch over udl and remove the
> > driver's implementation.
> >
> > Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
> > ---
> >  drivers/gpu/drm/udl/udl_drv.h     |  5 ---
> >  drivers/gpu/drm/udl/udl_fb.c      | 67 -------------------------------
> >  drivers/gpu/drm/udl/udl_modeset.c | 11 +++--
> >  3 files changed, 8 insertions(+), 75 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/udl/udl_drv.h b/drivers/gpu/drm/udl/udl_drv.h
> > index 77b57d6abd23..c6fd5c08f5fc 100644
> > --- a/drivers/gpu/drm/udl/udl_drv.h
> > +++ b/drivers/gpu/drm/udl/udl_drv.h
> > @@ -89,11 +89,6 @@ void udl_urb_completion(struct urb *urb);
> >  int udl_init(struct udl_device *udl);
> >  void udl_fini(struct drm_device *dev);
> >
> > -struct drm_framebuffer *
> > -udl_fb_user_fb_create(struct drm_device *dev,
> > -                     struct drm_file *file,
> > -                     const struct drm_mode_fb_cmd2 *mode_cmd);
> > -
> >  int udl_render_hline(struct drm_device *dev, int log_bpp, struct urb **urb_ptr,
> >                      const char *front, char **urb_buf_ptr,
> >                      u32 byte_offset, u32 device_byte_offset, u32 byte_width,
> > diff --git a/drivers/gpu/drm/udl/udl_fb.c b/drivers/gpu/drm/udl/udl_fb.c
> > index c1996ac73a1f..ed01ebaaf468 100644
> > --- a/drivers/gpu/drm/udl/udl_fb.c
> > +++ b/drivers/gpu/drm/udl/udl_fb.c
> > @@ -9,14 +9,9 @@
> >   */
> >
> >  #include <linux/moduleparam.h>
> > -#include <linux/dma-buf.h>
> >
> > -#include <drm/drm_crtc_helper.h>
> > -#include <drm/drm_drv.h>
> >  #include <drm/drm_fourcc.h>
> > -#include <drm/drm_gem_framebuffer_helper.h>
> >  #include <drm/drm_gem_shmem_helper.h>
> > -#include <drm/drm_modeset_helper.h>
> >
> >  #include "udl_drv.h"
> >
> > @@ -152,65 +147,3 @@ int udl_handle_damage(struct drm_framebuffer *fb, int x, int y,
> >         drm_gem_shmem_vunmap(fb->obj[0], vaddr);
> >         return ret;
> >  }
> > -
> > -static int udl_user_framebuffer_dirty(struct drm_framebuffer *fb,
> > -                                     struct drm_file *file,
> > -                                     unsigned flags, unsigned color,
> > -                                     struct drm_clip_rect *clips,
> > -                                     unsigned num_clips)
> > -{
> > -       struct udl_device *udl = fb->dev->dev_private;
> > -       struct dma_buf_attachment *import_attach;
> > -       int i;
> > -       int ret = 0;
> > -
> > -       drm_modeset_lock_all(fb->dev);
> > -
> > -       spin_lock(&udl->active_fb_16_lock);
> > -       if (udl->active_fb_16 != fb) {
> > -               spin_unlock(&udl->active_fb_16_lock);
> > -               goto unlock;
> > -       }
> > -       spin_unlock(&udl->active_fb_16_lock);
> > -
> > -       import_attach = fb->obj[0]->import_attach;
> > -
> > -       if (import_attach) {
> > -               ret = dma_buf_begin_cpu_access(import_attach->dmabuf,
> > -                                              DMA_FROM_DEVICE);
> > -               if (ret)
> > -                       goto unlock;
> > -       }
> > -
> > -       for (i = 0; i < num_clips; i++) {
> > -               ret = udl_handle_damage(fb, clips[i].x1, clips[i].y1,
> > -                                       clips[i].x2 - clips[i].x1,
> > -                                       clips[i].y2 - clips[i].y1);
> > -               if (ret)
> > -                       break;
> > -       }
> > -
> > -       if (import_attach)
> > -               ret = dma_buf_end_cpu_access(import_attach->dmabuf,
> > -                                            DMA_FROM_DEVICE);
> > -
> I cannot quite see how the existing atomic helper handles dma buf imports.
> There are no dma_buf_begin_cpu_access/dma_buf_end_cpu_access calls around.
> 
> From a quick look, imports don't seem to be prohibited in the helper.
> 
> Am I missing something? Alternatively can you add a brief note in the
> commit message.

Great catch, that's indeeded missing (and it was also missing from the
existing code except for the dirty path here). I think a prep patch to
move the begin/end_cpu_access into udl_handle_damage, before this entire
series here, would be best.
-Daniel

> 
> Thanks
> -Emil

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch