diff mbox series

[v2] drm/i915/display: Update calculation to avoid overflow

Message ID 20240614044213.377710-1-mitulkumar.ajitkumar.golani@intel.com (mailing list archive)
State New
Headers show
Series [v2] drm/i915/display: Update calculation to avoid overflow | expand

Commit Message

Golani, Mitulkumar Ajitkumar June 14, 2024, 4:42 a.m. UTC
Update calculation to avoid overflow.

-v2:
Remove extra line between cc and signed-off.

Fixes: 1676ecd303ac ("drm/i915: Compute CMRR and calculate vtotal")
Cc: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Cc: Suraj Kandpal <suraj.kandpal@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
---
 drivers/gpu/drm/i915/display/intel_vrr.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

Comments

Lucas De Marchi June 14, 2024, 2:17 p.m. UTC | #1
On Fri, Jun 14, 2024 at 10:12:13AM GMT, Mitul Golani wrote:
>Update calculation to avoid overflow.
>
>-v2:
>Remove extra line between cc and signed-off.
>
>Fixes: 1676ecd303ac ("drm/i915: Compute CMRR and calculate vtotal")
>Cc: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
>Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
>Cc: Suraj Kandpal <suraj.kandpal@intel.com>
>Cc: Jani Nikula <jani.nikula@linux.intel.com>
>Cc: Stephen Rothwell <sfr@canb.auug.org.au>
>Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
>Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>


Acked-by: Lucas De Marchi <lucas.demarchi@intel.com>

Lucas De Marchi
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
index eb5b62b54d32..6430da25957d 100644
--- a/drivers/gpu/drm/i915/display/intel_vrr.c
+++ b/drivers/gpu/drm/i915/display/intel_vrr.c
@@ -147,10 +147,11 @@  cmrr_get_vtotal(struct intel_crtc_state *crtc_state, bool video_mode_required)
 		multiplier_n = 1000;
 	}
 
-	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;
-	adjusted_pixel_rate = adjusted_mode->crtc_clock * 1000 * multiplier_m;
+	crtc_state->cmrr.cmrr_n = mul_u32_u32(desired_refresh_rate * adjusted_mode->crtc_htotal,
+					      multiplier_n);
+	vtotal = DIV_ROUND_UP_ULL(mul_u32_u32(adjusted_mode->crtc_clock * 1000, multiplier_n),
+				  crtc_state->cmrr.cmrr_n);
+	adjusted_pixel_rate = mul_u32_u32(adjusted_mode->crtc_clock * 1000, multiplier_m);
 	crtc_state->cmrr.cmrr_m = do_div(adjusted_pixel_rate, crtc_state->cmrr.cmrr_n);
 
 	return vtotal;