From 44d0237a26395ac94160cf23f32769013b365590 Mon Sep 17 00:00:00 2001 From: Mark Yao Date: Fri, 29 Apr 2016 11:37:20 +0800 Subject: [PATCH] drm/rockchip: vop: fix iommu crash with async atomic After async atomic_commit callback, drm_atomic_clean_old_fb will clean all old fb, but because async, the old fb may be also on the vop hardware, dma will access the old fb buffer, clean old fb will cause iommu page fault. Reference the fb and unreference it when the fb actuall swap out from vop hardware. Signed-off-by: Mark Yao --- drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c index 28596e72df2b..8652bb132395 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c @@ -560,6 +560,22 @@ static void vop_plane_destroy(struct drm_plane *plane) drm_plane_cleanup(plane); } +static int vop_plane_prepare_fb(struct drm_plane *plane, + const struct drm_plane_state *new_state) +{ + if (plane->state->fb) + drm_framebuffer_reference(plane->state->fb); + + return 0; +} + +static void vop_plane_cleanup_fb(struct drm_plane *plane, + const struct drm_plane_state *old_state) +{ + if (old_state->fb) + drm_framebuffer_unreference(old_state->fb); +} + static int vop_plane_atomic_check(struct drm_plane *plane, struct drm_plane_state *state) { @@ -756,6 +772,8 @@ static void vop_plane_atomic_update(struct drm_plane *plane, } static const struct drm_plane_helper_funcs plane_helper_funcs = { + .prepare_fb = vop_plane_prepare_fb, + .cleanup_fb = vop_plane_cleanup_fb, .atomic_check = vop_plane_atomic_check, .atomic_update = vop_plane_atomic_update, .atomic_disable = vop_plane_atomic_disable, -- 2.20.1