[PATCH 6/7] drm/i915: Switch intel_usecs_to_scanlines() to 64bit maths

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Dotclocks can reach ~1GHz these days, so intel_usecs_to_scanlines(),
with its 32bit maths, is currently limited to a few milliseconds.
I want bigger numbers in DSB selftests, so switch over to 64bit
maths.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_crtc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_crtc.c b/drivers/gpu/drm/i915/display/intel_crtc.c
index ca6dc1dc56c8..17edd6099287 100644
--- a/drivers/gpu/drm/i915/display/intel_crtc.c
+++ b/drivers/gpu/drm/i915/display/intel_crtc.c
@@ -454,8 +454,8 @@ int intel_usecs_to_scanlines(const struct drm_display_mode *adjusted_mode,
 	if (!adjusted_mode->crtc_htotal)
 		return 1;
 
-	return DIV_ROUND_UP(usecs * adjusted_mode->crtc_clock,
-			    1000 * adjusted_mode->crtc_htotal);
+	return DIV_ROUND_UP_ULL(mul_u32_u32(usecs, adjusted_mode->crtc_clock),
+				1000 * adjusted_mode->crtc_htotal);
 }
 
 /**
-- 
2.44.1