On Sat, Jun 26, 2010 at 7:56 PM, Zhenyu Wang <zhen...@linux.intel.com> wrote: > On 2010.06.25 16:21:40 +1000, Dave Airlie wrote: >> From: Dave Airlie <airl...@redhat.com> >> >> We've just gotten an eDP laptop, and kms was booting to a black screen. >> >> as much as I hate Keith's magic * 3, it seems to work a lot better than the >> non-magic. >> >> aligning the non-magic seems to make things a lot happier, and aligns better >> with what the bios appears to do, since the bios ends up using thehigher >> clock in VGA mode. >> >> Signed-off-by: Dave Airlie <airl...@redhat.com> >> --- >> drivers/gpu/drm/i915/intel_dp.c | 2 +- >> 1 files changed, 1 insertions(+), 1 deletions(-) >> >> diff --git a/drivers/gpu/drm/i915/intel_dp.c >> b/drivers/gpu/drm/i915/intel_dp.c >> index 6094e42..80e122d 100644 >> --- a/drivers/gpu/drm/i915/intel_dp.c >> +++ b/drivers/gpu/drm/i915/intel_dp.c >> @@ -133,7 +133,7 @@ intel_dp_link_required(struct drm_device *dev, >> struct intel_dp_priv *dp_priv = intel_encoder->dev_priv; >> >> if (IS_eDP(intel_encoder) || IS_PCH_eDP(dp_priv)) >> - return (pixel_clock * dev_priv->edp_bpp) / 8; >> + return (pixel_clock * ALIGN(dev_priv->edp_bpp, 8)) / 8; >> else >> return pixel_clock * 3; >> } >> -- > > Dave, we've found this breaks one 1600x900 eDP panel on our side, although > it might fix other panels requiring high rate even low rate can fit. > > Modeline 0:"1600x900" 0 107840 1600 1691 1752 1904 900 906 917 944 0x8 0x0 > > Clock is 107840khz, and the color depth is 18. Max number of lane from DPCD > is 1. So with your change, it will exceed 2.7Ghz. > > We've been told that we should try from highest config to lower ones until > training can succeed, that seems the only stable way to get correct clock > for eDP. >
Can you try the latest patch I send to the list? it uses the overheads given in the eDP spec, but they should apply to normal DP as well. Dave. _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
