[PATCH v2 1/3] drm/vmwgfx: Determine lock-waiting timeout from vblank state

[Thomas Zimmermann <tzimmermann@suse.de>]

Use the calculated duration of a frame as stored in the vblank state
for the lock-waiting timeout. Decouples the waiting from the details
of the vblank implementation. Both values should be equal.

This will be helpful for replacing vmwgfx's vblank timer with DRM's
common implementation.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/vmwgfx/vmwgfx_vkms.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_vkms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_vkms.c
index 5abd7f5ad2db..7862f6972512 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_vkms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_vkms.c
@@ -516,9 +516,13 @@ vmw_vkms_set_crc_surface(struct drm_crtc *crtc,
 static inline u64
 vmw_vkms_lock_max_wait_ns(struct vmw_display_unit *du)
 {
-	s64 nsecs = ktime_to_ns(du->vkms.period_ns);
+	struct drm_crtc *crtc = &du->crtc;
+	struct drm_vblank_crtc *vblank = drm_crtc_vblank_crtc(crtc);
+
+	if (!vblank || !vblank->framedur_ns)
+		return NSEC_PER_SEC / 60; /* disabled; assume 60 Hz */
 
-	return  (nsecs > 0) ? nsecs : 16666666;
+	return vblank->framedur_ns;
 }
 
 /**
-- 
2.54.0