[0/4] Implement Wa_14021768792 to bypass m_n ratio limit

Message

Nautiyal, Ankit K Sept. 17, 2024, 5:41 p.m. UTC

For Platforms that support higher link rates, there is a limitation on
Link M /Link N ratio.
If the CEILING( Link M / Link N ) ratio is greater than 10.0, then
hardware cannot support the given resolution / refresh rate at the given
configuration.
For BMG Wa_14021768792 helps to bypass this limitation and allows it to
support the ratio till 15.0.

This series adds the missing restrictions for earlier platforms and adds
the Wa_14021768792 for BMG as per Bspec:49266

Rev2:
-Drop new member link_n_extended.
-Avoid WA framework for XE

Ankit Nautiyal (4):
  Add bits for link_n_exended for DISPLAY >= 14
  drm/i915/display: Limit m/n ratio to 10 for display > 12
  drm/i915/display: Add bits for Wa_14021768792 for linkm/n ratio > 10
  drm/i915/display: Implement Wa_14021768792 for BMG DP for link_m/n
    ratio > 10

 drivers/gpu/drm/i915/display/intel_display.c  | 147 ++++++++++++++++--
 drivers/gpu/drm/i915/display/intel_display.h  |  15 +-
 .../drm/i915/display/intel_display_types.h    |   2 +
 drivers/gpu/drm/i915/display/intel_dp.c       |  62 ++++++--
 drivers/gpu/drm/i915/display/intel_dp.h       |   5 +
 drivers/gpu/drm/i915/display/intel_dp_mst.c   |  37 +++--
 drivers/gpu/drm/i915/display/intel_fdi.c      |  15 +-
 .../gpu/drm/i915/display/intel_pch_display.c  |   4 +-
 drivers/gpu/drm/i915/i915_reg.h               |   7 +
 9 files changed, 243 insertions(+), 51 deletions(-)