From 2d1b50564734619487745fe14dc2999b1f4a15d2 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Fri, 29 Jul 2016 17:57:01 +0300 Subject: [PATCH] drm/i915: Always use cpp==4 for FW_BLC_SELF on 915GM/945GM MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Bspec says: "FW_BLC_SELF ... Programming Note [DevALV] and [DevCST]: When calculating watermark values for 15/16bpp, assume 32bpp for purposes of calculation using the high priority bandwidth analysis spreadsheet." Let's do that. Perhaps this might even help with the problem that resulted in commit 2ab1bc9df01d ("drm/i915: Disable self-refresh for untiled fbs on i915gm") Cc: Daniel Vetter Cc: Chris Wilson Signed-off-by: Ville Syrjälä Link: http://patchwork.freedesktop.org/patch/msgid/1469804222-12650-1-git-send-email-ville.syrjala@linux.intel.com Reviewed-by: Chris Wilson --- drivers/gpu/drm/i915/intel_pm.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index b5513d3a2df8..e2eee775da46 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -1604,6 +1604,9 @@ static void i9xx_update_wm(struct drm_crtc *unused_crtc) unsigned long line_time_us; int entries; + if (IS_I915GM(dev) || IS_I945GM(dev)) + cpp = 4; + line_time_us = max(htotal * 1000 / clock, 1); /* Use ns/us then divide to preserve precision */ -- 2.20.1