On 12/03/24 15:27, Melissa Wen wrote: > On 03/06, Arthur Grillo wrote: >> As well noted by Pekka[1], the rounding of drm_fixp2int_round is wrong. >> To round a number, you need to add 0.5 to the number and floor that, >> drm_fixp2int_round() is adding 0.0000076. Make it add 0.5. >> >> [1]: https://lore.kernel.org/all/20240301135327.22efe0dd.pekka.paalanen@xxxxxxxxxxxxx/ >> > Hi Arthur, > > thanks for addressing this issue. > > Please, add a fix tag to the commit that you are fixing, so we can > easily backport. Might be this commit: > https://cgit.freedesktop.org/drm/drm-misc/commit/drivers/gpu/drm/vkms?id=ab87f558dcfb2562c3497e89600dec798a446665 >> Suggested-by: Pekka Paalanen <pekka.paalanen@xxxxxxxxxxxxx> >> Signed-off-by: Arthur Grillo <arthurgrillo@xxxxxxxxxx> >> --- >> include/drm/drm_fixed.h | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/include/drm/drm_fixed.h b/include/drm/drm_fixed.h >> index 0c9f917a4d4b..de3a79909ac9 100644 >> --- a/include/drm/drm_fixed.h >> +++ b/include/drm/drm_fixed.h >> @@ -90,7 +90,7 @@ static inline int drm_fixp2int(s64 a) >> >> static inline int drm_fixp2int_round(s64 a) >> { >> - return drm_fixp2int(a + (1 << (DRM_FIXED_POINT_HALF - 1))); > Also, this is the only usage of DRM_FIXED_POINT_HALF. Can you also > remove it as it won't be used anymore? > >> + return drm_fixp2int(a + DRM_FIXED_ONE / 2); > Would this division be equivalent to just shifting 1ULL by 31 instead of > 32 as done in DRM_FIXED_ONE? Yes, but I think the division makes it easier to understand what is going on. Best Regards, ~Arthur Grillo > > Melissa > >> } >> >> static inline int drm_fixp2int_ceil(s64 a) >> >> -- >> 2.43.0 >>