On Wed, 2012-03-14 at 17:44 +0100, Takashi Iwai wrote: > At Wed, 14 Mar 2012 10:45:06 -0400, > Adam Jackson wrote: > > There may or may not be a bit for this in the VBT in the BIOS. But the > > more reliably correct thing I suspect would be to just look at the > > preferred mode for the panel and assume it's dual-link LVDS if the pixel > > clock is >112MHz, since that's the crossover frequency. > > Coincidently, we hit the same issue with a HP laptop, and wondered how > is the best way to fix. I hoped BIOS could handle better, > i.e. setting the power bits no matter whether the lid is opened or > not. But it doesn't set unless the lid is once opened. > > (Interestingly, the bits remain even if you close the lid again before > booting. Just opening once seems triggering the probing of LVDS > panel in BIOS and let it setting the right values.) > > FWIW, when I check ironalke_crtc_mode_set(), the clock of the HD+ > LVDS mode (1600x900) is 107800 (refclk 120000), while a similar > machine with a HD panel (1366x768) shows 76300. So, I'm not sure > whether 112MHz could be a right threshold. Hm, fair point. Would be interesting to compare the VBTs between the two boots. The lvds_fp_timing struct might actually have the data we want here regardless of how the machine booted. - ajax -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 198 bytes Desc: This is a digitally signed message part URL: <http://lists.freedesktop.org/archives/intel-gfx/attachments/20120314/22ab3fed/attachment-0001.pgp>
