998d2cd361
At the moment modesetting pipe C on IVB will fail if pipe B uses 4 FDI lanes. Make the BW sharing more dynamic by trying to reduce pipe B's link bpp in this case, until pipe B uses only up to 2 FDI lanes. For this instead of the encoder compute config retry loop - which reduced link bpp only for the encoder's pipe - reduce the maximum link bpp for pipe B/C as required after all CRTC states are computed and recompute the CRTC states with the new bpp limit. Atm, all FDI encoder's compute config function returns an error if a BW constrain prevents increasing the pipe bpp value. The corresponding crtc_state->bw_constrained check can be replaced with checking crtc_state->max_link_bpp_x16, add TODO comments for this. SDVO is an exception where this case is only handled in the outer config retry loop, failing the modeset with a WARN, add a FIXME comment to handle this in the encoder code similarly to other encoders. v2: - Don't assume that a CRTC is already in the atomic state, while reducing its link bpp. - Add DocBook description to intel_fdi_atomic_check_link(). v3: - Enable BW management for FDI links in a separate patch. (Ville) v4: (Ville) - Fail the SDVO encoder config computation if it doesn't support the link bpp limit. - Add TODO: comments about checking link_bpp_x16 instead of bw_constrained. v5: - Replace link bpp limit check with a FIXME: comment in intel_sdvo_compute_config(). (Ville) Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> [Amended commit message wrt. changes in v5] Signed-off-by: Imre Deak <imre.deak@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20230921195159.2646027-11-imre.deak@intel.com
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.