drm/i915/fdi: Recompute state for affected CRTCs on FDI links

Recompute the state of all CRTCs on an FDI link during a modeset that
may be affected by the modeset of other CRTCs on the same link. This
ensures that each CRTC on the link maximizes its BW use (after another
CRTC is disabled).

In practice this means recomputing pipe B's config on IVB if pipe C gets
disabled.

v2:
- Add the change recomputing affected CRTC states in a separate patch.
(Ville)
v3: (Ville)
- Constify old and new crtc states.
- Check for fused off pipe C.
- Fix new vs. old crtc state mixup.
- Drop check for pipe C's enabled state.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230921195159.2646027-12-imre.deak@intel.com

drm/i915/fdi: Improve FDI BW sharing between pipe B and C

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

drm/i915: Move intel_ddi_fdi_post_disable() to fdi code

Reanme intel_ddi_fdi_post_disable() to hsw_fdi_disable() and
relocate it next to all the other code dealing with FDI_RX.
intel_ddi.c has now been cleansed of FDI_RX.

In order to avoid exposing intel_disable_ddi_buf() outside
intel_ddi.c we can just open code the DDI_BUF_CTL write. The
enable side already has all that stuff open coded so
this actually is more symmetric. But we do need to remeber
to bring the intel_wait_ddi_buf_idle() call over from
inside intel_disable_ddi_buf().

Cc: Dave Airlie <airlied@redhat.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211015071625.593-9-ville.syrjala@linux.intel.com
Reviewed-by: Dave Airlie <airlied@redhat.com>

drm/i915: Move PCH refclock stuff into its own file

Move the PCH refclk stuff (including all the LPT/WPT
iCLKIP/CLKOUT_DP things) to its own file.

We also suck in the mPHY programming from intel_fdi.c
since we're the only caller.

Cc: Dave Airlie <airlied@redhat.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211015071625.593-2-ville.syrjala@linux.intel.com
Reviewed-by: Dave Airlie <airlied@redhat.com>

drm/i915/fdi: use -EAGAIN instead of local special return value

Using standard -EAGAIN should be perfectly fine instead of using a
special case value.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210930093229.28598-1-jani.nikula@intel.com

drm/i915/fdi: move fdi modeset asserts to intel_fdi.c

Keep the functionality and the assert code together.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/427d27eb4e5daca208d496d6c2ffc91ed90ba714.1632992608.git.jani.nikula@intel.com

drm/i915/display: add intel_fdi_link_train wrapper.

This wraps the fdi link training vfunc to make it clearer.

Suggested by Jani.

Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1bb978bcb6f16fbdaf08f2800a179b774525b59e.1632869550.git.jani.nikula@intel.com

drm/i915/fdi: move fdi mphy reset and programming to intel_fdi.c

This fairly detailed stuff that really has no place in
intel_display.c. Combine the calls into one to avoid exposing both.

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/b0037775480380e5d73d0b112da478d6f0ea30fe.1629906431.git.jani.nikula@intel.com

drm/i915/fdi: move more FDI stuff to FDI link train hooks

Accept slight duplication in the fdi link train hooks in exchange for
simplification in ilk_pch_enable(). This lets us make
ivb_update_fdi_bc_bifurcation() static again, now in intel_fdi.c.

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/7984e670c6bb092d213d90f838d526d594d4a690.1629906431.git.jani.nikula@intel.com

drm/i915/fdi: move fdi bc bifurcation functions to intel_fdi.c

Move FDI related functions to intel_fdi.c. Don't bother with renaming as
we'll make the functions static shortly.

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/fd8afe4876f0b0762a9c69e01762a8dba31349e5.1629906431.git.jani.nikula@intel.com

drm/i915/fdi: move intel_update_fdi_pll_freq to intel_fdi.c

Move FDI related functions to intel_fdi.c. Rename to have intel_fdi
prefix while at it.

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/da1609dfce4623f8ec86254aea6c2c8679b6a37f.1629906431.git.jani.nikula@intel.com

drm/i915/fdi: make intel_fdi_link_freq() return int

The unsigned doesn't help us here.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210823093645.10464-1-jani.nikula@intel.com

drm/i915/fdi: move intel_fdi_link_freq() to intel_fdi.[ch]

There's no performance reason to have it as static inline; move it out
of intel_display_types.h to reduce clutter and dependency on i915_drv.h.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/8c9bb23d92878deb1ecc75427ec6648bd3505816.1629281426.git.jani.nikula@intel.com

drm/i915: migrate hsw fdi code to new file.

Daniel asked for this, but it's a bit messy and I'm not sure
how best to clean it up yet.

Signed-off-by: Dave Airlie <airlied@redhat.com>
[Jani: also moved fdi buf trans to intel_fdi.c.]
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/44491f2465549ea5c2e48cde5437fa232f77ab96.1612467466.git.jani.nikula@intel.com

drm/i915: split fdi code out from intel_display.c

This just refactors out the fdi code to a separate file.

Signed-off-by: Dave Airlie <airlied@redhat.com>
[Jani: cleaned up intel_fdi.h a bit.]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/f9d52c3d91f0973af308ede16e266fc9b753ecf9.1610622609.git.jani.nikula@intel.com