Dne sreda, 18. marec 2026 ob 10:35:35 Srednjeevropski standardni čas je Chen-Yu Tsai napisal(a): > Hi, > > On Tue, Mar 10, 2026 at 12:56 AM Chen-Yu Tsai <[email protected]> wrote: > > > > Commit 4636ce93d5b2 ("drm/fb-cma-helper: Add drm_fb_cma_get_gem_addr()") > > adds a new helper, which covers fetching a drm_framebuffer's GEM object > > and calculating the buffer address for a given plane. > > > > This patch uses this helper to replace our own open coded version of the > > same function. > > > > Signed-off-by: Chen-Yu Tsai <[email protected]> > > --- > > drivers/gpu/drm/sun4i/sun8i_ui_layer.c | 16 ++------------- > > drivers/gpu/drm/sun4i/sun8i_vi_layer.c | 27 ++------------------------ > > 2 files changed, 4 insertions(+), 39 deletions(-) > > > > diff --git a/drivers/gpu/drm/sun4i/sun8i_ui_layer.c > > b/drivers/gpu/drm/sun4i/sun8i_ui_layer.c > > index f08f6da55dd0..72c92203ae63 100644 > > --- a/drivers/gpu/drm/sun4i/sun8i_ui_layer.c > > +++ b/drivers/gpu/drm/sun4i/sun8i_ui_layer.c > > @@ -124,25 +124,13 @@ static void sun8i_ui_layer_update_buffer(struct > > sun8i_layer *layer, > > { > > struct drm_plane_state *state = plane->state; > > struct drm_framebuffer *fb = state->fb; > > - struct drm_gem_dma_object *gem; > > dma_addr_t dma_addr; > > u32 ch_base; > > - int bpp; > > > > ch_base = sun8i_channel_base(layer); > > > > - /* Get the physical address of the buffer in memory */ > > - gem = drm_fb_dma_get_gem_obj(fb, 0); > > - > > - DRM_DEBUG_DRIVER("Using GEM @ %pad\n", &gem->dma_addr); > > - > > - /* Compute the start of the displayed memory */ > > - bpp = fb->format->cpp[0]; > > - dma_addr = gem->dma_addr + fb->offsets[0]; > > - > > - /* Fixup framebuffer address for src coordinates */ > > - dma_addr += (state->src.x1 >> 16) * bpp; > > - dma_addr += (state->src.y1 >> 16) * fb->pitches[0]; > > + /* Get the start of the displayed memory */ > > + dma_addr = drm_fb_dma_get_gem_addr(fb, state, 0); > > I just realized while reading more code that there's a subtle difference > here. > > The original code used state->src.x1, which is the "clipped" coordinates, > while drm_fb_dma_get_gem_addr() uses state->src_x, which is the original > coordinates. > > Jernej, do you know which one the driver is supposed to use? Or maybe > it doesn't matter?
I would say that it doesn't matter for point of origin. Original coordinates use uint32_t values which means origin cannot be out of screen (negative numbers). What I found interesting is that clipped coordinates are int, e.g. they can be negative. Best regards, Jernej
