[PATCH v2 5/8] drm/rockchip: vop2: Enforce AFBC source alignment in plane_check

Nicolas Frattaroli
2025-12-06T20:46:22Z

From: Daniel Stone <daniels@collabora.com>

Planes can only source AFBC framebuffers at multiples of 4px wide on
RK3566/RK3568. Instead of clipping on all SoCs when the user asks for an
unaligned source rectangle, reject the configuration in the plane's
atomic check on RK3566/RK3568 only.

Signed-off-by: Daniel Stone <daniels@collabora.com>
[Make RK3566/RK3568 specific, reword message]
Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
---
drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
index bc1ed0ffede0..e23213337104 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
@@ -1076,6 +1076,13 @@ static int vop2_plane_atomic_check(struct drm_plane *plane,
return -EINVAL;
}

+ if (vop2->version == VOP_VERSION_RK3568 && drm_is_afbc(fb->modifier) && src_w % 4) {
+ drm_dbg_kms(vop2->drm,
+ "AFBC source rectangles must be 4-byte aligned; is %d\n",
+ src_w);
+ return -EINVAL;
+ }
+
return 0;
}

@@ -1237,11 +1244,8 @@ static void vop2_plane_atomic_update(struct drm_plane *plane,
WARN_ON(src_w < 4);
WARN_ON(src_h < 4);

- if (afbc_en && src_w % 4) {
- drm_dbg_kms(vop2->drm, "vp%d %s src_w[%d] not 4 pixel aligned\n",
- vp->id, win->data->name, src_w);
- src_w = ALIGN_DOWN(src_w, 4);
- }
+ if (vop2->version == VOP_VERSION_RK3568 && drm_is_afbc(fb->modifier))
+ WARN_ON(src_w % 4);

act_info = (src_h - 1) << 16 | ((src_w - 1) & 0xffff);
dsp_info = (dsp_h - 1) << 16 | ((dsp_w - 1) & 0xffff);

--
2.52.0