HyperV's virtual hardware does not provide vblank interrupts. Use a
vblank timer to simulate the interrupt. Rate-limits the display's
update frequency to the display-mode settings. Avoids excessive CPU
overhead with compositors that do not rate-limit their output.
Signed-off-by: Thomas Zimmermann <tzimmerm...@suse.de>
Reviewed-by: Javier Martinez Canillas <javi...@redhat.com>
---
drivers/gpu/drm/hyperv/hyperv_drm_modeset.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
b/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
index 945b9482bcb3..6e6eb1c12a68 100644
--- a/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
+++ b/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
@@ -19,6 +19,8 @@
#include <drm/drm_probe_helper.h>
#include <drm/drm_panic.h>
#include <drm/drm_plane.h>
+#include <drm/drm_vblank.h>
+#include <drm/drm_vblank_helper.h>
#include "hyperv_drm.h"
@@ -111,11 +113,15 @@ static void hyperv_crtc_helper_atomic_enable(struct
drm_crtc *crtc,
crtc_state->mode.hdisplay,
crtc_state->mode.vdisplay,
plane_state->fb->pitches[0]);
+
+ drm_crtc_vblank_on(crtc);
}
static const struct drm_crtc_helper_funcs hyperv_crtc_helper_funcs = {
.atomic_check = drm_crtc_helper_atomic_check,
+ .atomic_flush = drm_crtc_vblank_atomic_flush,
.atomic_enable = hyperv_crtc_helper_atomic_enable,
+ .atomic_disable = drm_crtc_vblank_atomic_disable,
};
static const struct drm_crtc_funcs hyperv_crtc_funcs = {
@@ -125,6 +131,7 @@ static const struct drm_crtc_funcs hyperv_crtc_funcs = {
.page_flip = drm_atomic_helper_page_flip,
.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
+ DRM_CRTC_VBLANK_TIMER_FUNCS,
};
static int hyperv_plane_atomic_check(struct drm_plane *plane,
@@ -321,6 +328,10 @@ int hyperv_mode_config_init(struct hyperv_drm_device *hv)
return ret;
}
+ ret = drm_vblank_init(dev, 1);
+ if (ret)
+ return ret;
+
drm_mode_config_reset(dev);
return 0;
--
2.50.1
