From 4b5a51e45f296f0477485cadd1fb7e03295cc455 Mon Sep 17 00:00:00 2001 From: Thomas Zimmermann Date: Thu, 22 Sep 2022 15:09:44 +0200 Subject: [PATCH] drm/simpledrm: Synchronize access to GEM BOs Synchronize CPU access to GEM BOs with other drivers when updating the screen buffer. Imported buffers might otherwise contain stale data. Signed-off-by: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Link: https://patchwork.freedesktop.org/patch/msgid/20220922130944.27138-6-tzimmermann@suse.de --- drivers/gpu/drm/tiny/simpledrm.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/tiny/simpledrm.c b/drivers/gpu/drm/tiny/simpledrm.c index 5f242558891e..18489779fb8a 100644 --- a/drivers/gpu/drm/tiny/simpledrm.c +++ b/drivers/gpu/drm/tiny/simpledrm.c @@ -480,10 +480,14 @@ static void simpledrm_primary_plane_helper_atomic_update(struct drm_plane *plane struct simpledrm_device *sdev = simpledrm_device_of_dev(dev); struct drm_atomic_helper_damage_iter iter; struct drm_rect damage; - int idx; + int ret, idx; + + ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE); + if (ret) + return; if (!drm_dev_enter(dev, &idx)) - return; + goto out_drm_gem_fb_end_cpu_access; drm_atomic_helper_damage_iter_init(&iter, old_plane_state, plane_state); drm_atomic_for_each_plane_damage(&iter, &damage) { @@ -499,6 +503,8 @@ static void simpledrm_primary_plane_helper_atomic_update(struct drm_plane *plane } drm_dev_exit(idx); +out_drm_gem_fb_end_cpu_access: + drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE); } static void simpledrm_primary_plane_helper_atomic_disable(struct drm_plane *plane,