[Intel-gfx] [PATCH 0/6] drm/i915: Some FDI related dotclock stuff

ville.syrjala at linux.intel.com ville.syrjala at linux.intel.com
Wed Feb 17 19:41:07 UTC 2016

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Imre's SNB had a crappy BIOS that failed to configure the hardware
correctly when hooked up to a 4K monitor, which then resulted in
lots of noise from i915 when it was trying to make sense of the bad
state. That spurred me to reorganize the FDI dotclock vs. encoder
dotclock sanity check we have in the encoder .get_config() hooks.
And while doing that I figured we might as well try to read out
the actual VGA dotclock via sideband on HSW/BDW, which can then
be compared to the one compute from FDI parameters.

Apparently a BIOS update solved the problem for Imre, but I think
these patches still have some value by adding more thorough state
cross checking on HSW/BDW, and just moving out the sanity checks
from the state readout code makes quite a bit of sense to me, 
especially if we run into more buggy BIOSen. Though if people
prefer, I could respin these without that particular change,
ie. just keep the LPT-H dotclock readout and cross checking

I also ended up fixing the port clock limits for CRT for various

Ville Syrjälä (6):
  drm/i915: Dump ddi_pll_sel in hex instead of decimal on HSW/BDW
  drm/i915: Move the encoder vs. FDI dotclock check out from encoder
  drm/i915: Remove the SPLL==270Mhz assumption from
  drm/i915: Make the LPT iclkip 20MHz case more generic
  drm/i915: Read out VGA dotclock properly on LPT
  drm/i915: Try to fix CRT port clock limits

 drivers/gpu/drm/i915/i915_reg.h      |   8 +-
 drivers/gpu/drm/i915/intel_crt.c     |  30 ++++----
 drivers/gpu/drm/i915/intel_display.c | 143 +++++++++++++++++++++++------------
 drivers/gpu/drm/i915/intel_dp.c      |  11 +--
 drivers/gpu/drm/i915/intel_drv.h     |   4 +-
 drivers/gpu/drm/i915/intel_hdmi.c    |   3 -
 drivers/gpu/drm/i915/intel_lvds.c    |   8 +-
 drivers/gpu/drm/i915/intel_sdvo.c    |   4 +-
 8 files changed, 123 insertions(+), 88 deletions(-)


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