drm/i915/dp: Factor out intel_dp_read_dprx_caps()

Factor out a function to read the sink's DPRX capabilities used by a
follow-up patch enabling the DP tunnel BW allocation mode.

Reviewed-by: Uma Shankar <uma.shankar@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/20240220211841.448846-10-imre.deak@intel.com

i915/display/dp: SDP CRC16 for 128b132b link layer

Enable SDP error detection configuration, this will set CRC16 in
128b/132b link layer.
For Display version 13 a hardware bit31 in register VIDEO_DIP_CTL is
added to enable/disable SDP CRC applicable for DP2.0 only, but the
default value of this bit will enable CRC16 in 128b/132b hence
skipping this write.
Corrective actions on SDP corruption is yet to be defined.

v2: Moved the CRC enable to link training init(Jani N)
v3: Moved crc enable to ddi pre enable <Jani N>
v4: Separate function for SDP CRC16 (Jani N)

Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230302081532.765821-3-arun.r.murthy@intel.com

drm: Rename dp/ to display/

Rename dp/ to display/ to account for additional display-related
helpers, such as HDMI. Update all related include statements. No
functional changes.

Various drivers, such as i915 and amdgpu, use similar naming scheme
by putting code for video-output standards into a local display/
directory. The new directory's name is aligned with this convention.

v2:
* update commit message (Javier)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220421073108.19226-3-tzimmermann@suse.de

drm/i915/dp: add 128b/132b support to link status checks

Abstract link status check to a function that takes 128b/132b and 8b/10b
into account, and use it. Also dump link status on failures.

Cc: Uma Shankar <uma.shankar@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
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/cec395d435679a290a1c35fcbfc54555101bfad1.1643878928.git.jani.nikula@intel.com

drm/dp: Move public DisplayPort headers into dp/

Move all public DisplayPort headers into dp/ and update users. No
functional changes.

v3:
* rebased onto latest drm-tip

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220114114535.29157-5-tzimmermann@suse.de

drm/i915: Show LTTPR in the TPS debug print

Indicate which LTTPR we're currently attempting to train when
we print which training pattern we're using.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211004170535.4173-3-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>

drm/i915: Relocate intel_dp_program_link_training_pattern()

intel_dp_program_link_training_pattern() clearly belongs in
intel_dp_link_training.c. Make it so.

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210318161015.22070-4-ville.syrjala@linux.intel.com

drm/i915: Disable LTTPR support when the DPCD rev < 1.4

By the specification the 0xF0000-0xF02FF range is only valid when the
DPCD revision is 1.4 or higher. Disable LTTPR support if this isn't so.

Trying to detect LTTPRs returned corrupted values for the above DPCD
range at least on a Skylake host with an LG 43UD79-B monitor with a DPCD
revision 1.2 connected.

v2: Add the actual version check.
v3: Fix s/DRPX/DPRX/ typo.

Fixes: 7b2a4ab8b0ef ("drm/i915: Switch to LTTPR transparent mode link training")
Cc: <stable@vger.kernel.org> # v5.11
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210317190149.4032966-1-imre.deak@intel.com

drm/i915: Disable LTTPR support when the DPCD rev < 1.4

By the specification the 0xF0000-0xF02FF range is only valid when the
DPCD revision is 1.4 or higher. Disable LTTPR support if this isn't so.

Trying to detect LTTPRs returned corrupted values for the above DPCD
range at least on a Skylake host with an LG 43UD79-B monitor with a DPCD
revision 1.2 connected.

v2: Add the actual version check.
v3: Fix s/DRPX/DPRX/ typo.

Fixes: 7b2a4ab8b0ef ("drm/i915: Switch to LTTPR transparent mode link training")
Cc: <stable@vger.kernel.org> # v5.11
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210317190149.4032966-1-imre.deak@intel.com
(cherry picked from commit 264613b406eb0d74cd9ca582c717c5e2c5a975ea)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915/dp: Fix LTTPR vswing/pre-emp setting in non-transparent mode

The DP PHY vswing/pre-emphasis level programming the driver does is
related to the DPTX -> first LTTPR link segment only. Accordingly it
should be only programmed when link training the first LTTPR and kept
as-is when training subsequent LTTPRs and the DPRX. For these latter
PHYs the vs/pe levels will be set in response to writing the
DP_TRAINING_LANEx_SET_PHY_REPEATERy DPCD registers (by an upstream LTTPR
TX PHY snooping this write access of its downstream LTTPR/DPRX RX PHY).
The above is also described in DP Standard v2.0 under 3.6.6.1.

While at it simplify and add the LTTPR that is link trained to the debug
message in intel_dp_set_signal_levels().

Fixes: b30edfd8d0b4 ("drm/i915: Switch to LTTPR non-transparent mode link training")
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201229172201.4155327-2-imre.deak@intel.com

drm/i915/dp: Move intel_dp_set_signal_levels() to intel_dp_link_training.c

intel_dp_set_signal_levels() is needed for link training, so move it to
intel_dp_link_training.c.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201229172201.4155327-1-imre.deak@intel.com

drm/i915/dp: Fix LTTPR vswing/pre-emp setting in non-transparent mode

The DP PHY vswing/pre-emphasis level programming the driver does is
related to the DPTX -> first LTTPR link segment only. Accordingly it
should be only programmed when link training the first LTTPR and kept
as-is when training subsequent LTTPRs and the DPRX. For these latter
PHYs the vs/pe levels will be set in response to writing the
DP_TRAINING_LANEx_SET_PHY_REPEATERy DPCD registers (by an upstream LTTPR
TX PHY snooping this write access of its downstream LTTPR/DPRX RX PHY).
The above is also described in DP Standard v2.0 under 3.6.6.1.

While at it simplify and add the LTTPR that is link trained to the debug
message in intel_dp_set_signal_levels().

Fixes: b30edfd8d0b4 ("drm/i915: Switch to LTTPR non-transparent mode link training")
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201229172201.4155327-2-imre.deak@intel.com
(cherry picked from commit 67fba3f1c73b83569d171ae1fa463a537bbfe0a8)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

drm/i915/dp: Move intel_dp_set_signal_levels() to intel_dp_link_training.c

intel_dp_set_signal_levels() is needed for link training, so move it to
intel_dp_link_training.c.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201229172201.4155327-1-imre.deak@intel.com
(cherry picked from commit 1c6e527d6947ea77bebabe15bbeaa765a87b70ca)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

drm/i915: Switch to LTTPR non-transparent mode link training

The DP Standard's recommendation is to use the LTTPR non-transparent
mode link training if LTTPRs are detected, so let's do this.

Besides power-saving, the advantages of this are that the maximum number
of LTTPRs can only be used in non-transparent mode (the limit is 5-8 in
transparent mode), and it provides a way to narrow down the reason for a
link training failure to a given link segment. Non-transparent mode is
probably also the mode that was tested the most by the industry.

The changes in this patchset:
- Pass the DP PHY that is currently link trained to all LT helpers, so
that these can access the correct LTTPR/DPRX DPCD registers.
- During LT take into account the LTTPR common lane rate/count and the
per LTTPR-PHY vswing/pre-emph limits.
- Switch to LTTPR non-transparent LT mode and train each link segment
according to the sequence in DP Standard v2.0 (complete CR/EQ for
each segment before continuing with the next segment).

v2:
- Switch to non-transparent mode during connector detection, which is
required before reading the per-PHY LTTPR capabilities.
- Move the DP_PHY_LTTPR() macro to drm_dp_helper.h (Ville)
- Use the new drm_dp_dpcd_read_phy_link_status() instead of adding the
same logic to intel_dp_get_link_status(). (Ville)
- Make intel_dp_lttpr_phy_caps() return a pointer to the whole array
instead of a pointer to its first element. (Ville)
- Add the intel_dp_phy_is_downstream_of_source() helper. (Ville)
- Add a code comment about the disable->enable quirk of
non-transparent mode.
- Add the intel_dp_training_pattern_set_reg() helper.
- Fix checkpatch/sparse warns.

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/20201007170917.1764556-7-imre.deak@intel.com

drm/i915: Switch to LTTPR transparent mode link training

By default LTTPRs should be in transparent link training mode,
nevertheless in this patch we switch to this default mode explicitly.

The DP Standard recommends this, supposedly because an LTTPR may be left
in the non-transparent mode (by BIOS, previous kernel, or after reset
due to a firmware bug). I haven't seen this happening, but let's follow
the DP Standard.

v2:
- Add a code comment about the explicit disabling of non-transparent
mode.
v3:
- Move check to prevent initing LTTPRs on eDP to init_dp_lttpr_init().

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/20201007170917.1764556-6-imre.deak@intel.com

drm/i915: Fix DP link training pattern mask

An LTTPR can be trained with training pattern 4 even if the DPCD
revision is < 1.4, but drm_dp_training_pattern_mask() would change
pattern 4 to pattern 3 on those DPCD revisions.

Since intel_dp_training_pattern() makes already sure that the proper
training pattern is used, all that needs to be masked out is the
scrambling disable flag, which is or'd to the mask later based on the
training pattern.

v2:
- Use a helper instead of open-coding the masking. (Ville)

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/20201007170917.1764556-2-imre.deak@intel.com

drm/i915: Plumb crtc_state to link training

Get rid of mode crtc->config usage, and some ad-hoc intel_dp state
usage by plumbing the crtc state all the way down to the link training
code.

Unfortunately we do have to keep some cached state in intel_dp so
that we can do the "does the link need retraining?" checks from
the short hpd handler.

v2: Add intel_crtc_state forward declaration
v3: Don't kill the PHY test code totally since it's
now in the hotplug work where we can get at the states
v4: Don't resurrect the debug scrambling disable bit (Imre)
Use intel_dp_mst_is_master_trans() (Imre)

Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201001111053.24451-1-ville.syrjala@linux.intel.com

drm/i915/dp: Made intel_dp_adjust_train() non-static

vswing/pre-emphasis adjustment calculation is needed in processing
of auto phy compliance request other than link training, so have
made non-static function.

No functional change.

v1: initial patch.
v2:
- used "intel_dp" prefix in function name. (Jani)
- used array notation instead pointer for link_status. (Ville)
v3: Scrapped the initial patch, modified commit description accordingly.
- made non-static function and used intel_dp prefix. (Jani, Manasi)

Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200316103759.12867-4-animesh.manna@intel.com

drm/i915: move modesetting output/encoder code under display/

Add a new subdirectory for display code, and start off by moving
modesetting output/encoder code. Judging by the include changes, this is
a surprisingly clean operation.

v2:
- move intel_sdvo_regs.h too
- use tabs for Makefile file lists and sort them

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613084416.6794-2-jani.nikula@intel.com