blob: 10f5bc059493ba8e8dab05c936218305c6ea7491 [file] [log] [blame]
From f663ca0720a1c16536b78181f95962160e7bdedb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@linux.intel.com>
Date: Mon, 14 Oct 2013 14:50:30 +0300
Subject: drm/i915: Use DIV_ROUND_CLOSEST() to calculate dot/vco
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Rounding down when calculating the dot/vco frequencies doesn't make much
sense. Round to closest should give slightly nicer answers.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit fb03ac0106bcc1d5576f1e94161e41a2ef4da1f3)
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
---
drivers/gpu/drm/i915/intel_display.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 548b1c914a1f..32cd88cb8580 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -329,8 +329,8 @@ static void vlv_clock(int refclk, intel_clock_t *clock)
{
clock->m = clock->m1 * clock->m2;
clock->p = clock->p1 * clock->p2;
- clock->vco = refclk * clock->m / clock->n;
- clock->dot = clock->vco / clock->p;
+ clock->vco = DIV_ROUND_CLOSEST(refclk * clock->m, clock->n);
+ clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p);
}
/**
@@ -430,8 +430,8 @@ static void pineview_clock(int refclk, intel_clock_t *clock)
{
clock->m = clock->m2 + 2;
clock->p = clock->p1 * clock->p2;
- clock->vco = refclk * clock->m / clock->n;
- clock->dot = clock->vco / clock->p;
+ clock->vco = DIV_ROUND_CLOSEST(refclk * clock->m, clock->n);
+ clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p);
}
static uint32_t i9xx_dpll_compute_m(struct dpll *dpll)
@@ -443,8 +443,8 @@ static void i9xx_clock(int refclk, intel_clock_t *clock)
{
clock->m = i9xx_dpll_compute_m(clock);
clock->p = clock->p1 * clock->p2;
- clock->vco = refclk * clock->m / (clock->n + 2);
- clock->dot = clock->vco / clock->p;
+ clock->vco = DIV_ROUND_CLOSEST(refclk * clock->m, clock->n + 2);
+ clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p);
}
#define INTELPllInvalid(s) do { /* DRM_DEBUG(s); */ return false; } while (0)
--
1.8.5.rc3