[PATCH] drm/i915/display: Update vtotal math to address 32b build

[Golani, Mitulkumar Ajitkumar]

Hi Jani,

Change is floated to gfx as well. Also we clubbed to one other fix,

https://patchwork.freedesktop.org/series/134801/

Floated on both xe and gfx mailing list.

Regards,
Mitul

> -----Original Message-----
> From: Jani Nikula <jani.nikula at linux.intel.com>
> Sent: Thursday, June 13, 2024 11:55 AM
> To: Golani, Mitulkumar Ajitkumar <mitulkumar.ajitkumar.golani at intel.com>;
> intel-xe at lists.freedesktop.org
> Subject: Re: [PATCH] drm/i915/display: Update vtotal math to address 32b
> build
> 
> On Wed, 12 Jun 2024, Mitul Golani <mitulkumar.ajitkumar.golani at intel.com>
> wrote:
> > Fix vtotal division calculation which works for 32b systems.
> 
> This should be sent to intel-gfx (too).
> 
> BR,
> Jani.
> 
> >
> > Fixes: 1676ecd303ac ("drm/i915: Compute CMRR and calculate vtotal")
> > Cc: Mitul Golani <mitulkumar.ajitkumar.golani at intel.com>
> > Cc: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
> > Cc: Suraj Kandpal <suraj.kandpal at intel.com>
> > Cc: Jani Nikula <jani.nikula at linux.intel.com>
> > Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.golani at intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_vrr.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c
> b/drivers/gpu/drm/i915/display/intel_vrr.c
> > index 05f67dc9d98d..1e37383e14e7 100644
> > --- a/drivers/gpu/drm/i915/display/intel_vrr.c
> > +++ b/drivers/gpu/drm/i915/display/intel_vrr.c
> > @@ -149,7 +149,8 @@ cmrr_get_vtotal(struct intel_crtc_state *crtc_state,
> bool video_mode_required)
> >
> >  	crtc_state->cmrr.cmrr_n =
> >  		desired_refresh_rate * adjusted_mode->crtc_htotal *
> multiplier_n;
> > -	vtotal = (adjusted_mode->crtc_clock * 1000 * multiplier_n) /
> crtc_state->cmrr.cmrr_n;
> > +	vtotal = DIV_ROUND_UP_ULL(adjusted_mode->crtc_clock * 1000 *
> multiplier_n,
> > +				  crtc_state->cmrr.cmrr_n);
> >  	adjusted_pixel_rate = adjusted_mode->crtc_clock * 1000 *
> multiplier_m;
> >  	crtc_state->cmrr.cmrr_m = do_div(adjusted_pixel_rate, crtc_state-
> >cmrr.cmrr_n);
> 
> --
> Jani Nikula, Intel