[PATCH v2 1/2] drm/rockchip: vop: clear DMA stop bit upon vblank on RK3066

[Val Packett <val@packett.cool>]

On the RK3066, there is a bit that must be cleared, otherwise
the picture does not show up on the display (at least for RGB).

Fixes: f4a6de8 ("drm: rockchip: vop: add rk3066 vop definitions")
Cc: stable@vger.kernel.org
Signed-off-by: Val Packett <val@packett.cool>
---
v2: doing this on vblank makes more sense; added fixes tag
---
 drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 6 ++++++
 drivers/gpu/drm/rockchip/rockchip_drm_vop.h | 1 +
 drivers/gpu/drm/rockchip/rockchip_vop_reg.c | 1 +
 3 files changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
index a13473b2d..2731fe2b2 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
@@ -1766,6 +1766,12 @@ static void vop_handle_vblank(struct vop *vop)
 	}
 	spin_unlock(&drm->event_lock);
 
+	if (VOP_HAS_REG(vop, common, dma_stop)) {
+		spin_lock(&vop->reg_lock);
+		VOP_REG_SET(vop, common, dma_stop, 0);
+		spin_unlock(&vop->reg_lock);
+	}
+
 	if (test_and_clear_bit(VOP_PENDING_FB_UNREF, &vop->pending))
 		drm_flip_work_commit(&vop->fb_unref_work, system_unbound_wq);
 }
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.h b/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
index b33e5bdc2..0cf512cc1 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
@@ -122,6 +122,7 @@ struct vop_common {
 	struct vop_reg lut_buffer_index;
 	struct vop_reg gate_en;
 	struct vop_reg mmu_en;
+	struct vop_reg dma_stop;
 	struct vop_reg out_mode;
 	struct vop_reg standby;
 };
diff --git a/drivers/gpu/drm/rockchip/rockchip_vop_reg.c b/drivers/gpu/drm/rockchip/rockchip_vop_reg.c
index b9ee02061..9bcb40a64 100644
--- a/drivers/gpu/drm/rockchip/rockchip_vop_reg.c
+++ b/drivers/gpu/drm/rockchip/rockchip_vop_reg.c
@@ -466,6 +466,7 @@ static const struct vop_output rk3066_output = {
 };
 
 static const struct vop_common rk3066_common = {
+	.dma_stop = VOP_REG(RK3066_SYS_CTRL0, 0x1, 0),
 	.standby = VOP_REG(RK3066_SYS_CTRL0, 0x1, 1),
 	.out_mode = VOP_REG(RK3066_DSP_CTRL0, 0xf, 0),
 	.cfg_done = VOP_REG(RK3066_REG_CFG_DONE, 0x1, 0),
-- 
2.45.1