From 898ec8cd3a18e5c2af4e5a434cf8cdfca0d4aa83 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Sat, 28 Jun 2014 00:40:34 +0300 Subject: [PATCH] drm/i915: Fix threshold for choosing 32 vs. 64 precisions for VLV DDL values MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The DDL registers can hold 7bit numbers. Make the most of those seven bits by adjusting the threshold where we switch between the 64 vs. 32 precision multipliers. Also we compute 'entries' to make the decision about precision, and then we recompute the same value to calculate the actual drain latency. Just use the already calculate 'entries' there. Reviewed-by: Paulo Zanoni Signed-off-by: Ville Syrjälä Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_pm.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 91edd47e9bce7..615e341682c39 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -1287,15 +1287,14 @@ static bool vlv_compute_drain_latency(struct drm_device *dev, pixel_size = crtc->primary->fb->bits_per_pixel / 8; /* BPP */ entries = (clock / 1000) * pixel_size; - *plane_prec_mult = (entries > 256) ? + *plane_prec_mult = (entries > 128) ? DRAIN_LATENCY_PRECISION_64 : DRAIN_LATENCY_PRECISION_32; - *plane_dl = (64 * (*plane_prec_mult) * 4) / ((clock / 1000) * - pixel_size); + *plane_dl = (64 * (*plane_prec_mult) * 4) / entries; entries = (clock / 1000) * 4; /* BPP is always 4 for cursor */ - *cursor_prec_mult = (entries > 256) ? + *cursor_prec_mult = (entries > 128) ? DRAIN_LATENCY_PRECISION_64 : DRAIN_LATENCY_PRECISION_32; - *cursor_dl = (64 * (*cursor_prec_mult) * 4) / ((clock / 1000) * 4); + *cursor_dl = (64 * (*cursor_prec_mult) * 4) / entries; return true; } -- 2.39.5