On 6/12/2024 3:24 PM, Mitul Golani wrote:
Update calculation to avoid overflow.
Fixes: 1676ecd303ac ("drm/i915: Compute CMRR and calculate vtotal")
Cc: Mitul Golani <mitulkumar.ajitkumar.golani@xxxxxxxxx>
Cc: Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx>
Cc: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.golani@xxxxxxxxx>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx>
---
drivers/gpu/drm/i915/display/intel_vrr.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
index dc9cf7ddafe9..5da9d5b9936e 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;
