The 128b/132b channel coding link training uses more straightforward TX
FFE preset values. Reuse voltage tries and max vswing for retry logic.
The delays for 128b/132b are still all wrong, but this is regardless a
step forward.
v2: Fix UHBR rate checks, use intel_dp_is_uhbr() helper
v3:
- Rebase
- Modify intel_dp_adjust_request_changed() and
intel_dp_link_max_vswing_reached() to take 128b/132b into
account. (Ville)
v4:
- Train request printing for TX FFE (Ville)
- Log 8b/10b vs. 128b/132b (Ville)
- Add helper for per-lane max vswing / tx ffe (Ville)
- Name functions with tx_ffe/vswing instead of 128b132b/8b10b
Cc: 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/20211011182144.22074-2-jani.nikula@intel.com
Add per-lane abstraction for max vswing reached to make follow-up
cleaner, as this one reverses the conditions.
v2: both conditions need to be true, reverse (Ville)
Cc: 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/20211011182144.22074-1-jani.nikula@intel.com
Add a function for checking source MST support. Drop intel_dp->can_mst
and use intel_dp->mst_mgr.cbs to indicate the same. It's the single
point of truth without additional state variables. In code, "source
support" is also self-documenting as opposed to the vague "can mst".
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/20211006101618.22066-1-jani.nikula@intel.com
Limit the supported UHBR rates based on the repeater support, if there
are repeaters.
This should be done in DP helper level, but that requires an overhaul of
the LTTPR handling, as the max rate is not enough to represent how
128b/132b rates may be masked along the way.
Curiously, the spec says:
* Shall be cleared to 00h when operating in 8b/10b Link Layer.
* Each LTTPR on the way back to the DPTX shall clear the bits that do
not correspond to the LTTPR's current bit rate.
It's rather vague if we can reliably use the field at this time due to
the wording "operating" and "current". But it would seem bizarre to have
to wait until trying to operate a 128b/132b link layer at a certain bit
rate to figure this out.
Cc: 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/20211007105727.18439-1-jani.nikula@intel.com
The UHBR check was using > instead of >=. Use the helper instead to
avoid mistakes. Also always use the non-UHBR values for HDMI.
v2: Use intel_crtc_has_dp_encoder() && intel_dp_is_uhbr() (Ville)
Fixes: 2817efaeb6 ("drm/i915/dg2: add SNPS PHY translations for UHBR link rates")
Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: 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/20211007124201.18686-1-jani.nikula@intel.com
As per the comment on top of acpi_evaluate_dsm():
| * Evaluate device's _DSM method with specified GUID, revision id and
| * function number. Caller needs to free the returned object.
We should free the returned object of acpi_evaluate_dsm() to avoid memory
leakage. Otherwise the kmemleak splat will be triggered at boot time (if we
compile kernel with CONFIG_DEBUG_TEST_DRIVER_REMOVE=y).
Fixes: 8e55f99c51 ("drm/i915: Invoke another _DSM to enable MUX on HP Workstation laptops")
Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210906033541.862-1-yuzenghui@huawei.com
I suppose intel_dp_dump_link_status() might be useful for diagnosing
link training failures. Hoever we only call from the channel EQ phase
currently. Let's call it from the CR phase as well.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211004170535.4173-6-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>
Unify all debug prints during link training to include information
on both the encoder and the LTTPR. We unify the format to something
like "[ENCODER:1:FOO][LTTPR 1] Something something". Though not
sure if those brackets around the dp_phy just make it look like
line noise? I'll accept suggestions on better formatting.
I'm slightly on the fence about also including the connector,
but technically only the DPRX is the SST connector (ie.
intel_dp->attached_connector). I suppose you could think of it
as the branch device/whatever in the topology, and we're training
the link leading to it. So that could argue for its inclusion.
But it's all getting a bit long alrady, so not going to do it
I think.
v2: Keep the connector name in the final passed/failed debug print
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211004170535.4173-5-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>
Currently we consider the max vswing reached when we transmit a
the max voltage level, but we don't consider pre-emphasis at all.
This kinda matches older DP specs that only had some vague text
about transmitting the maximum voltage swing. Latest versions
now say something vague about consider the sum of the vswing
and pre-emphasis fields in the ADJUST_REQUEST_LANE registers.
Very vague, and super confusing especially the fact that it
talks about transmitted voltgage swing in the same sentence
as it say to look at the requested values.
Also glanced at the link CTS spec, and that one seems to have
tests that assume contradicting behaviour. Some say to consider
just the vswing level we transmit, others say to check for
sum of transmitted vswing+preemph being 3.
So let's try to take some kind of sane middle ground here.
I think what could make sense is only consider max vswing
reached if MAX_SWING_REACHED==1 _and_ vswing+preemph==3.
That will allow things to go all the way up to vswing 3 +
pre-emph 0 or vswing 2 + pre-emph 1, depending on what
the maximum supported vswing is. Only considering the sum
of vswing+pre-emph doesn't make much sense to me since
we could terminate too early if the sink requests eg.
vswing 0 + pre-emph 3. And if we'd stick to the current
code we could terminate too early of the sink asks for
vswing 2 + pre-emph 0 when vswing level 3 is not supported.
Side note: I don't really understand why any of this stuff is
"specified" at all. There is already a limit of 5 attempts at
the same vswing+pre-emph level, and a total limit of 10
attempts. So might as well stick to the same max 5 attempts
across the board IMO.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211004170535.4173-2-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>
The "digi_port" pointer can't be NULL and we have already dereferenced
it so checking for NULL is not necessary. Delete the check.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211004103737.GC25015@kili
Since the VT-d vs. async flip issues are plaguing a wider range
of supported hw let's try to minimize the impact on normal
operation by flipping the relevant chicken bits on and off
as needed. I presume there is some power/perf impact on since
this is reducing some prefetching I think.
Cc: Karthik B S <karthik.b.s@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210930190943.17547-2-ville.syrjala@linux.intel.com
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Looks like skl/bxt/derivatives also need the plane stride
stretch w/a when using async flips and VT-d is enabled, or
else we get corruption on screen. To my surprise this was
even documented in bspec, but only as a note on the
CHICHKEN_PIPESL register description rather than on the
w/a list.
So very much the same thing as on HSW/BDW, except the bits
moved yet again.
Cc: stable@vger.kernel.org
Cc: Karthik B S <karthik.b.s@intel.com>
Fixes: 55ea1cb178 ("drm/i915: Enable async flips in i915")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210930190943.17547-1-ville.syrjala@linux.intel.com
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
LTTPRs should support per-lane drive settings I think, and even if
they don't they should implement their own fallback logic to determine
suitable common drive settings to use for all the lanes.
v2: Actually check the correct thing
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/20211001130107.1746-11-ville.syrjala@linux.intel.com
Adjust the link training code to accommodate per-lane drive settings,
if supported by the platform. Actually enabling this will involve
some changes to each platform's .set_signal_level() implementation,
so for the moment all supported platforms will keep using the current
codepath that just uses the same drive settings for all the lanes.
v2: Fix min() vs. max() fumble
v3: Compact the debug print to a single line
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/20211001130107.1746-10-ville.syrjala@linux.intel.com
In order to have per-lane drive settings we need intel_ddi_level()
to accept the lane as a parameter. That is, the eventual goal is to
call intel_ddi_level() once for each lane. For now we just pass in
a hardcoded 0 and use the same settings for every lane. Ie. no
change in behaviour yet.
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/20211001130107.1746-9-ville.syrjala@linux.intel.com
Since intel_ddi_level() now looks at the buf_trans table there's
no point in having intel_ddi_hdmi_num_entries() around. Just
roll the necessary bits of locic into
intel_ddi_hdmi_level()/intel_ddi_level().
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/20211001130107.1746-8-ville.syrjala@linux.intel.com
All callers of intel_ddi_level() duplicate the check+WARN
to make sure the returned level is actually present in the
appropriate buf_trans table. Let's push that stuff into
intel_ddi_level() so the callers don't have to worry about it.
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/20211001130107.1746-7-ville.syrjala@linux.intel.com
Currently .set_signal_levels() is only used by encoders in DP mode.
For most modern platforms there is no essential difference between
DP and HDMI, and both codepaths just end up calling the same function
under the hood. Let's get remove the need for that extra indirection
by moving .set_signal_levels() into the encoder from intel_dp.
Since we already plumb the crtc_state/etc. into .set_signal_levels()
the code will do the right thing for both DP and HDMI.
HSW/BDW/SKL are the only platforms that need a bit of care on
account of having to preload the hardware buf_trans register
with the full set of values. So we must still remember to call
hsw_prepare_{dp,hdmi}_ddi_buffers() to do said preloading, and
.set_signal_levels() will just end up selecting the correct entry
for DP, and also setting up the iboost magic for both DP and HDMI.
Note that previously on HSW/BDW/SKL we did write to DDI_BUF_CTL to
select the correct entry until link training started, now that we
call .set_signal_levels() already from hsw_ddi_pre_enable_dp() that
is no longer the case. But it's all safe now that the
intel_ddi_init_dp_buf_reg() call was hoisted up and it no longer
sets up the DDI_BUF_CTL_ENABLE bit (that is still deferred until
link training).
v2: Rebase due to has_{iboost,buf_trans_select}()
Add some notes about the DDI_BUF_CTL situation on HSW/BDW/SKL (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/20211001130107.1746-4-ville.syrjala@linux.intel.com
Add a small helper to determine if DDI_BUF_CTL uses the
DDI_BUF_TRANS_SELECT field, and whether we have the
accompanying DDI_BUF_TRANS table in the hardware.
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211001130107.1746-3-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>
The DP spec says:
"If the receiver keeps the same value in the ADJUST_REQUEST_LANEx_y
register(s) while the LANEx_CR_DONE bits remain unset, the transmitter
must loop four times with the same voltage swing. On the fifth time,
the transmitter must down-shift to the lower bit rate and must repeat
the CR-lock training sequence as described below."
Lets fix the code to follow that instead of terminating after five
times of transmitting the same signal levels. The text in spec feels
a little bit ambiguous still, but this is my best guess at its meaning.
As a bonus this also gets rid of the train_set[0] stuff which
would not work for per-lane drive settings anyway.
Cc: Imre Deak <imre.deak@intel.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/20211001160826.17080-1-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>
While sanitizing the hardware state we're currently forcing
the pipe bottom color legacy csc/gamma bits on. That is not a
good idea as BIOSen are likely to leave gabage in the LUTs and
so doing this causes ugly visual glitches if and when the
planes covering the background get disabled. This was exactly
the case on this Dell Precision 5560 tgl laptop.
On icl+ we don't normally even use these legacy bits
anymore and instead use their GAMMA_MODE counterparts.
On earlier platforms the bits are used, but we still
shouldn't force them on without knowing what's in the LUT.
So two options, get rid of the whole thing, or do what
intel_color_commit() does to make sure the bottom color state
matches whatever out hardware readout produced. I chose the
latter since it'll match what happens on older platforms when
the primary plane gets turned off. In fact let's just call
intel_color_commit(). It'll also do some CSC programming but
since we don't have readout for that it'll actually just set
to all zeros. So in the unlikely case of CSC actually being
enabld by the BIOS we'll end up with all black until the first
atomic commit happens.
Still not totally sure what we should do about color management
features here in general. Probably the safest thing would be to
force everything off exactly at the same time when we disable
the primary plane as there is no guarantees that whatever the
LUTs/CSCs contain make any sense whatsoever without the
specific pixel data in the BIOS fb. And if we preserve the
primary plane then we should disable the color management
features exactly when the primary plane fb contents first
changes since the new content assumes more or less no
transformations. But of course synchronizing front buffer
rendering with anything else is a bit hard...
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/3534
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210928185105.3030-1-ville.syrjala@linux.intel.com
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
"CRTC fixup failed" is probably leftovers from pre-atomic days
when there was an actual fixup() function. Let's unify the debug
messages between encoder vs. crtc compute_config() calls.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210930104133.30854-2-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Having two functions for this seems like excess duplication and
parameter juggling. Merge them together.
While at it, drop the extra error message, as wait_for_payload_credits()
already prints an error, and switch from incidental -EPERM (i.e. -1) to
actual error codes.
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/f74f7462a36e76070db6b4c01616d0eb663b9938.1633000838.git.jani.nikula@intel.com
Move assert_panel_unlocked() to intel_pps.c and rename
assert_pps_unlocked(). Keep the functionality and the assert code
together.
There's still a bit of a split between the eDP PPS usage in intel_pps.c
and all the other PPS usage, and assert_pps_unlocked() is arguably more
related to the latter. However, intel_pps.c is the best fit for anything
touching the PPS registers.
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/a9b77692a145891789eefb0447e082cfc22aaa85.1632992608.git.jani.nikula@intel.com