From 65aac17423284634169489f298169c3e3f099cc7 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Mon, 10 Sep 2018 20:30:39 +0200 Subject: [PATCH] staging: vboxvideo: Change address of scanout buffer on page-flip Commit 2408898e3b6c ("staging: vboxvideo: Add page-flip support") only calls vbox_crtc_do_set_base() on page-flips, but despite that function's name it only pins the new fb, unpins the old fb and sets vbox_crtc->fb_offset. It does not program the hardware to scan out at the new vbox_crtc->fb_offset value. This was causing only every other frame (assuming page-flipping between 2 buffers) to be shown since we kept scanning out of the old (now unpinned!) buffer. This commit fixes this by adding code to vbox_crtc_page_flip() to tell the hardware to scanout from the new fb_offset. Fixes: 2408898e3b6c ("staging: vboxvideo: Add page-flip support") Cc: Steve Longerbeam Signed-off-by: Hans de Goede Signed-off-by: Greg Kroah-Hartman --- drivers/staging/vboxvideo/vbox_mode.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/staging/vboxvideo/vbox_mode.c b/drivers/staging/vboxvideo/vbox_mode.c index a83eac8..79836c8 100644 --- a/drivers/staging/vboxvideo/vbox_mode.c +++ b/drivers/staging/vboxvideo/vbox_mode.c @@ -323,6 +323,11 @@ static int vbox_crtc_page_flip(struct drm_crtc *crtc, if (rc) return rc; + mutex_lock(&vbox->hw_mutex); + vbox_set_view(crtc); + vbox_do_modeset(crtc, &crtc->mode); + mutex_unlock(&vbox->hw_mutex); + spin_lock_irqsave(&drm->event_lock, flags); if (event) -- 2.7.4