From e37c67a1c5743ac7fc7f946290fee96f84248ca7 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Fri, 13 Jun 2014 13:37:51 +0300 Subject: [PATCH] drm/i915: Use 200MHz cdclk on vlv when all pipes are off MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Drop the cdclk frequency to 200MHz on vlv when all pipes are off. In theory we should be able to use 200MHz also when the pixel clock is at most 90% of 200MHz. However in practice all we seem to get is a solid color picture or an otherwise corrupted display. Signed-off-by: Ville Syrjälä Reviewed-by: Jesse Barnes Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_display.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 5940011..d127e76 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -4556,14 +4556,19 @@ static int valleyview_calc_cdclk(struct drm_i915_private *dev_priv, * 400MHz * So we check to see whether we're above 90% of the lower bin and * adjust if needed. + * + * We seem to get an unstable or solid color picture at 200MHz. + * Not sure what's wrong. For now use 200MHz only when all pipes + * are off. */ if (max_pixclk > freq_320*9/10) return 400000; else if (max_pixclk > 266667*9/10) return freq_320; - else + else if (max_pixclk > 0) return 266667; - /* Looks like the 200MHz CDclk freq doesn't work on some configs */ + else + return 200000; } /* compute the max pixel clock for new configuration */ -- 2.7.4