[Intel-gfx] [PATCH 25/26] drm/i915: Round to closest in M/N calculations

[Ville Syrjala]

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

Rounding to nearest is what we do for most other clock calculations
so should probably do that for M/N too.

TODO: GOP seems to truncate instead so fastboot is going to be
a PITA to get right. Not sure what to do about it yet.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_display.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 89a7c8c1be28..c4257630a3fe 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -2856,7 +2856,7 @@ static void compute_m_n(u32 *ret_m, u32 *ret_n,
 	else
 		*ret_n = min_t(unsigned int, roundup_pow_of_two(n), DATA_LINK_N_MAX);
 
-	*ret_m = div_u64(mul_u32_u32(m, *ret_n), n);
+	*ret_m = DIV_ROUND_CLOSEST_ULL(mul_u32_u32(m, *ret_n), n);
 	intel_reduce_m_n_ratio(ret_m, ret_n);
 }
 
@@ -4602,7 +4602,8 @@ int intel_dotclock_calculate(int link_freq,
 	if (!m_n->link_n)
 		return 0;
 
-	return div_u64(mul_u32_u32(m_n->link_m, link_freq), m_n->link_n);
+	return DIV_ROUND_CLOSEST_ULL(mul_u32_u32(m_n->link_m, link_freq),
+				     m_n->link_n);
 }
 
 /* Returns the currently programmed mode of the given encoder. */
-- 
2.35.1