Hi,
On 2023/5/17 01:06, Thomas Zimmermann wrote:
Am 16.05.23 um 18:59 schrieb Sui Jingfeng:
Both mode->crtc_htotal and mode->crtc_vtotal are u16 type,
mode->crtc_htotal * mode->crtc_vtotal will results a unsigned type.
Using a u32 is enough to store the result, but considering that the
result will be casted to u64 soon after. We use a u64 type directly.
So there no need to cast it to signed type and cast back then.
Signed-off-by: Sui Jingfeng <suijingfeng@xxxxxxxxxxx>
Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
Cc: Maxime Ripard <mripard@xxxxxxxxxx>
Cc: Thomas Zimmermann <tzimmermann@xxxxxxx>
Cc: David Airlie <airlied@xxxxxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Reviewed-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
Thanks a lot, thanks for the response time also.
---
drivers/gpu/drm/drm_vblank.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c
index 877e2067534f..d99c404b181b 100644
--- a/drivers/gpu/drm/drm_vblank.c
+++ b/drivers/gpu/drm/drm_vblank.c
@@ -622,7 +622,7 @@ void drm_calc_timestamping_constants(struct
drm_crtc *crtc,
/* Valid dotclock? */
if (dotclock > 0) {
- int frame_size = mode->crtc_htotal * mode->crtc_vtotal;
+ u64 frame_size = mode->crtc_htotal * mode->crtc_vtotal;
/*
* Convert scanline length in pixels and video
@@ -630,7 +630,7 @@ void drm_calc_timestamping_constants(struct
drm_crtc *crtc,
* in nanoseconds:
*/
linedur_ns = div_u64((u64) mode->crtc_htotal * 1000000,
dotclock);
- framedur_ns = div_u64((u64) frame_size * 1000000, dotclock);
+ framedur_ns = div_u64(frame_size * 1000000, dotclock);
/*
* Fields of interlaced scanout modes are only half a frame
duration.
