Commit Graph

167 Commits

Author SHA1 Message Date
Lyude Paul f58a435311 drm/dp, drm/i915: Add support for VESA backlights using PWM for brightness control
Now that we've added support to i915 for controlling panel backlights that
need PWM to be enabled/disabled, let's finalize this and add support for
controlling brightness levels via PWM as well. This should hopefully put us
towards the path of supporting _ALL_ backlights via VESA's DPCD interface
which would allow us to finally start trusting the DPCD again.

Note however that we still don't enable using this by default on i915 when
it's not needed, primarily because I haven't yet had a chance to confirm if
it's safe to do this on the one machine in Intel's CI that had an issue
with this: samus-fi-bdw. I have done basic testing of this on other
machines though, by manually patching i915 to force it into PWM-only mode
on some of my laptops.

v2:
* Correct documentation (thanks Doug!)
* Get rid of backlight caps

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Cc: Rajeev Nandan <rajeevny@codeaurora.org>
Cc: Satadru Pramanik <satadru@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211105183342.130810-5-lyude@redhat.com
2021-11-17 17:36:48 -05:00
Lyude Paul 646596485e drm/dp: Don't read back backlight mode in drm_edp_backlight_enable()
As it turns out, apparently some machines will actually leave additional
backlight functionality like dynamic backlight control on before the OS
loads. Currently we don't take care to disable unsupported features when
writing back the backlight mode, which can lead to some rather strange
looking behavior when adjusting the backlight.

So, let's fix this by just not reading back the current backlight mode on
initial enable. I don't think there should really be any downsides to this,
and this will ensure we don't leave any unsupported functionality enabled.

This should fix at least one (but not all) of the issues seen with DPCD
backlight support on fi-bdw-samus

v5:
* Just avoid reading back DPCD register - Doug Anderson

Signed-off-by: Lyude Paul <lyude@redhat.com>
Fixes: 867cf9cd73 ("drm/dp: Extract i915's eDP backlight code into DRM helpers")
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20211105183342.130810-4-lyude@redhat.com
2021-11-17 17:36:48 -05:00
Maxime Ripard 736638246e
Merge drm/drm-next into drm-misc-next
drm-misc-next hasn't been updated in a while and I need a post -rc2
state to merge some vc4 patches.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
2021-10-25 15:27:56 +02:00
Jani Nikula 02ed47aa6c drm/dp: reuse the 8b/10b link training delay helpers
Reuse the 8b/10b link training delay helpers. Functionally this skips
the check for invalid values for DPCD 1.4 and later at clock recovery
delay (as it's a fixed delay and bypasses the rd_interval) but the same
value will be checked and invalid values reported at channel
equalization.

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/20211014150059.28957-2-jani.nikula@intel.com
2021-10-19 11:30:27 +03:00
Jani Nikula ba3078dad1 drm/dp: add helpers to read link training delays
The link training delays are different and/or available in different
DPCD offsets depending on:

- Clock recovery vs. channel equalization
- DPRX vs. LTTPR
- 128b/132b vs. 8b/10b
- DPCD 1.4+ vs. earlier

Add helpers to get the correct delays in us, reading DPCD if
necessary. This is more straightforward than trying to retrofit the
existing helpers to take 128b/132b into account.

Having to pass in the DPCD receiver cap field seems unavoidable, because
reading it involves checking the revision and reading extended receiver
cap. So unfortunately the interface is mixed cached and read as needed.

v2: Remove delay_us < 0 check and the whole local var (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/20211014150059.28957-1-jani.nikula@intel.com
2021-10-19 11:29:51 +03:00
Jani Nikula c78b4a8572 drm/dp: add helper for extracting adjust 128b/132b TX FFE preset
The DP 2.0 128b/132b channel coding uses TX FFE presets instead of
vswing and pre-emphasis.

Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/4ba129c51aeb01a5f210de7026abe704a554a178.1631191763.git.jani.nikula@intel.com
2021-09-20 18:45:35 +03:00
Jani Nikula fc8a2b1e0f drm/dp: use more of the extended receiver cap
Extend the use of extended receiver cap at 0x2200 to cover
MAIN_LINK_CHANNEL_CODING_CAP in 0x2206, in case an implementation hides
the DP 2.0 128b/132b channel encoding cap.

v2: Extend to DP_RECEIVER_CAP_SIZE (Ville)

Cc: Lyude Paul <lyude@redhat.com>
Cc: dri-devel@lists.freedesktop.org
Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/649051cb896821147feee91aab1f2abc523c1353.1631191763.git.jani.nikula@intel.com
2021-09-20 18:44:43 +03:00
Jani Nikula 054ce0bce2 drm/dp: add DP 2.0 UHBR link rate and bw code conversions
The bw code equals link_rate / 0.27 Gbps only for 8b/10b link
rates. Handle DP 2.0 UHBR rates as special cases, though this is not
pretty.

Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/cab4edda8834d6b4db610fabb5e1f1f18ae33c2c.1631191763.git.jani.nikula@intel.com
2021-09-20 18:43:58 +03:00
Cai Huoqing 0ae865ef92 drm: Fix typo in comments
fix typo for drm

v1->v2:
respin with the change "iff ==> implies that"

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210730132729.376-1-caihuoqing@baidu.com
2021-08-02 10:19:43 +02:00
Douglas Anderson 64c0274fb1 drm/dp: Don't zero PWMGEN_BIT_COUNT when driver_pwm_freq_hz not specified
The function drm_edp_backlight_init() is defined such that the
"driver_pwm_freq_hz" parameter is optional--it's 0 if you don't want
to futz with it. If you follow this variable through, you'll find out
that if it's 0 we won't ever set the "bl->pwmgen_bit_count", leaving
it as 0.

That means that before using it in drm_edp_backlight_enable() we need
to check to see if it's non-zero.

Programming this field to zero was confusing the panel I tested with
(Samsung ATNA33XC20). The backlight still worked somewhat but the
brightness values didn't correspond to what they should have been.

Fixes: 867cf9cd73 ("drm/dp: Extract i915's eDP backlight code into DRM helpers")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210730084534.v2.1.If017efce7116ae8ba015ed7def840c390a0e0c77@changeid
2021-07-31 20:02:59 +02:00
Douglas Anderson 17a1837d07 drm/dp: For drm_panel_dp_aux_backlight(), init backlight as disabled
Even after the DP AUX backlight on my board worked OK after applying
the patch ("drm/panel-simple: Power the panel when probing DP AUX
backlight") [1], I still noticed some strange timeouts being reported
by ti_sn_aux_transfer(). Digging, I realized the problem was this:
* Even though `enabled` in `struct dp_aux_backlight` was false, the
  base backlight structure (`base` in that structure) thought that the
  backlight was powered on.
* If userspace wrote to sysfs in this state then we'd try to enable
  the backlight.
* Unfortunatley, enabling the backlight didn't work because the panel
  itself wasn't powered.

We can only use the backlight if the panel is on and the panel is not
officially on when we probe (it's temporarily just on enough for us to
talk to it).

The important thing we want here is to get `BL_CORE_FBBLANK` set since
userspace can't mess with that. This will keep us disabled until
drm_panel enables us, which means that the panel is enabled
first. Ideally we'd just set this in our `props` before calling
devm_backlight_device_register() but the comments in the header file
are pretty explicit that we're not supposed to much with the `state`
ourselves. Because of this, there may be a small window where the
backlight device is registered and someone could try to tweak with the
backlight. This isn't likely to happen and even if it did, I don't
believe this causes any huge problem.

[1] https://lore.kernel.org/lkml/20210714093334.1.Idb41f87e5abae4aee0705db7458b0097fc50e7ab@changeid/

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210714101744.1.Ifc22696b27930749915e383f0108b7bcdc015a6e@changeid
2021-07-15 08:03:29 -07:00
Douglas Anderson 072ed3431f drm/dp: Move panel DP AUX backlight support to drm_dp_helper
We were getting a depmod error:
  depmod: ERROR: Cycle detected: drm_kms_helper -> drm -> drm_kms_helper

It looks like the rule is that drm_kms_helper can call into drm, but
drm can't call into drm_kms_helper. That means we've got to move the
DP AUX backlight support into drm_dp_helper.

NOTE: as part of this, I didn't try to do any renames of the main
registration function. Even though it's in the drm_dp_helper, it still
feels very parallel to drm_panel_of_backlight().

Fixes: 10f7b40e4f ("drm/panel: add basic DP AUX backlight support")
Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reported-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Rajeev Nandan <rajeevny@codeaurora.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210712075933.v2.1.I23eb4cc5a680341e7b3e791632a635566fa5806a@changeid
2021-07-13 06:38:37 -07:00
Lyude Paul 867cf9cd73 drm/dp: Extract i915's eDP backlight code into DRM helpers
Since we're about to implement eDP backlight support in nouveau using the
standard protocol from VESA, we might as well just take the code that's
already written for this and move it into a set of shared DRM helpers.

Note that these helpers are intended to handle DPCD related backlight
control bits such as setting the brightness level over AUX, probing the
backlight's TCON, enabling/disabling the backlight over AUX if supported,
etc. Any PWM-related portions of backlight control are explicitly left up
to the driver, as these will vary from platform to platform.

The only exception to this is the calculation of the PWM frequency
pre-divider value. This is because the only platform-specific information
required for this is the PWM frequency of the panel, which the driver is
expected to provide if available. The actual algorithm for calculating this
value is standard and is defined in the eDP specification from VESA.

Note that these helpers do not yet implement the full range of features
the VESA backlight interface provides, and only provide the following
functionality (all of which was already present in i915's DPCD backlight
support):

* Basic control of brightness levels
* Basic probing of backlight capabilities
* Helpers for enabling and disabling the backlight

v3:
* Split out changes to i915's backlight code to separate patches to make it
  easier to review
v4:
* Style/spelling changes from Thomas Zimmermann
v5:
* Start using new drm_dbg_*() functions

Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Dave Airlie <airlied@gmail.com>
Cc: greg.depoire@gmail.com
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210514181504.565252-9-lyude@redhat.com
2021-06-09 13:35:22 -04:00
Lyude Paul 208d8b9d26 drm/dp: Fix bogus DPCD version check in drm_dp_read_downstream_info()
Ville pointed this out to me when fixing some issues in
drm_dp_read_downstream_info() - the DPCD version check here is bogus as
there's no DisplayPort versions prior to 1.0. The original code from i915
that this was extracted from actually did:

  dpcd[DP_DPCD_REV] == DP_DPCD_REV_10

Which is correct, and somehow got missed when extracting this function. So
let's fix this. Note that as far as I'm aware, I don't think this fixes any
actual issues users are hitting.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210507214209.554866-1-lyude@redhat.com
2021-05-10 16:26:07 -04:00
Lyude Paul 4fca55de56 drm/dp: Drop open-coded drm_dp_is_branch() in drm_dp_read_downstream_info()
Noticed this while fixing another issue in drm_dp_read_downstream_info(),
the open coded DP_DOWNSTREAMPORT_PRESENT check here just duplicates what we
already do in drm_dp_is_branch(), so just get rid of it.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210430223428.10514-2-lyude@redhat.com
2021-05-07 17:32:23 -04:00
Lyude Paul 205bb69a90 drm/dp: Handle zeroed port counts in drm_dp_read_downstream_info()
While the DP specification isn't entirely clear on if this should be
allowed or not, some branch devices report having downstream ports present
while also reporting a downstream port count of 0. So to avoid breaking
those devices, we need to handle this in drm_dp_read_downstream_info().

So, to do this we assume there's no downstream port info when the
downstream port count is 0.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Tested-by: Jérôme de Bretagne <jerome.debretagne@gmail.com>
Bugzilla: https://gitlab.freedesktop.org/drm/intel/-/issues/3416
Fixes: 3d3721ccb1 ("drm/i915/dp: Extract drm_dp_read_downstream_info()")
Cc: <stable@vger.kernel.org> # v5.10+
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210430223428.10514-1-lyude@redhat.com
2021-05-07 17:32:22 -04:00
Lyude Paul b1e7f5fdba drm/dp: Convert drm_dp_helper.c to using drm_err/drm_dbg_*()
Now that we've added a back-pointer to drm_device to drm_dp_aux, made
drm_dp_aux available to any functions in drm_dp_helper.c which need to
print to the kernel log, and ensured all of our logging uses a consistent
format, let's do the final step of the conversion and actually move
everything over to using drm_err() and drm_dbg_*().

This was done by using the following cocci script:

  @@
  expression list expr;
  @@

  (
  - DRM_DEBUG_KMS(expr);
  + drm_dbg_kms(aux->drm_dev, expr);
  |
  - DRM_DEBUG_DP(expr);
  + drm_dbg_dp(aux->drm_dev, expr);
  |
  - DRM_DEBUG_ATOMIC(expr);
  + drm_dbg_atomic(aux->drm_dev, expr);
  |
  - DRM_DEBUG_KMS_RATELIMITED(expr);
  + drm_dbg_kms_ratelimited(aux->drm_dev, expr);
  |
  - DRM_ERROR(expr);
  + drm_err(aux->drm_dev, expr);
  )

Followed by correcting the resulting line-wrapping in the results by hand.

v2:
* Fix indenting in drm_dp_dump_access

Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: Robert Foss <robert.foss@linaro.org>
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210423184309.207645-16-lyude@redhat.com
Reviewed-by: Dave Airlie <airlied@redhat.com>
2021-04-27 18:43:45 -04:00
Lyude Paul 427e59d3b5 drm/dp: Always print aux channel name in logs
Since we're about to convert everything in drm_dp_helper.c over to using
drm_dbg_*(), let's also make our logging more consistent in drm_dp_helper.c
while we're at it to ensure that we always print the name of the AUX
channel in question.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210423184309.207645-8-lyude@redhat.com
Reviewed-by: Dave Airlie <airlied@redhat.com>
2021-04-27 18:43:43 -04:00
Lyude Paul 0c4fada608 drm/dp: Pass drm_dp_aux to drm_dp*_link_train_channel_eq_delay()
So that we can start using drm_dbg_*() for
drm_dp_link_train_channel_eq_delay() and
drm_dp_lttpr_link_train_channel_eq_delay().

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210423184309.207645-7-lyude@redhat.com
Reviewed-by: Dave Airlie <airlied@redhat.com>
2021-04-27 18:43:42 -04:00
Lyude Paul 9e98666644 drm/dp: Pass drm_dp_aux to drm_dp_link_train_clock_recovery_delay()
So that we can start using drm_dbg_*() in
drm_dp_link_train_clock_recovery_delay().

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210423184309.207645-6-lyude@redhat.com
Reviewed-by: Dave Airlie <airlied@redhat.com>
2021-04-27 18:43:42 -04:00
Lyude Paul 3f3a6524f6 drm/dp: Clarify DP AUX registration time
The docs we had for drm_dp_aux_init() and drm_dp_aux_register() were mostly
correct, except for the fact that they made the assumption that all AUX
devices were grandchildren of their respective DRM devices. This is the
case for most normal GPUs, but is almost never the case with SoCs and
display bridges. So, let's fix this documentation to clarify when the right
time to use drm_dp_aux_init() or drm_dp_aux_register() is.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210423184309.207645-5-lyude@redhat.com
Reviewed-by: Dave Airlie <airlied@redhat.com>
2021-04-27 18:43:42 -04:00
Lyude Paul 6cba3fe433 drm/dp: Add backpointer to drm_device in drm_dp_aux
This is something that we've wanted for a while now: the ability to
actually look up the respective drm_device for a given drm_dp_aux struct.
This will also allow us to transition over to using the drm_dbg_*() helpers
for debug message printing, as we'll finally have a drm_device to reference
for doing so.

Note that there is one limitation with this - because some DP AUX adapters
exist as platform devices which are initialized independently of their
respective DRM devices, one cannot rely on drm_dp_aux->drm_dev to always be
non-NULL until drm_dp_aux_register() has been called. We make sure to point
this out in the documentation for struct drm_dp_aux.

v3:
* Add WARN_ON_ONCE() to drm_dp_aux_register() if drm_dev isn't filled out

Signed-off-by: Lyude Paul <lyude@redhat.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210423184309.207645-4-lyude@redhat.com
Reviewed-by: Dave Airlie <airlied@redhat.com>
2021-04-27 18:43:42 -04:00
Ankit Nautiyal 68a8c645b2 drm/dp_helper: Define options for FRL training for HDMI2.1 PCON
Currently the FRL training mode (Concurrent, Sequential) and
training type (Normal, Extended) are not defined properly and
are passed as bool values in drm_helpers for pcon
configuration for FRL training.

This patch:
-Add register masks for Sequential and Normal FRL training options.
-Fixes the drm_helpers for FRL Training configuration to use the
 appropriate masks.
-Modifies the calls to the above drm_helpers in i915/intel_dp as per
 the above change.

v2: Re-used the register masks for these options, instead of enum. (Ville)

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210323112422.1211-2-ankit.k.nautiyal@intel.com
2021-03-31 12:21:06 +03:00
Dave Airlie 32c3d9b0f5 - HDCP 2.2 and HDCP 1.4 Gen12 DP MST support (Anshuman)
- Fix DP vswing settings and handling (Imre, Ville)
 - Various display code clean-up (Jani, Ville)
 - Various display refactoring, including split out of pps, aux, and fdi (Ja\
 ni, Dave)
 - Add DG1 missing workarounds (Jose)
 - Fix display color conversion (Chris, Ville)
 - Try to guess PCH type even without ISA bridge (Zhenyu)
 - More backlight refactor (Lyude)
 - Support two CSC module on gen11 and later (Lee)
 - Async flips for all ilk+ platforms (Ville)
 - Clear color support for TGL (RK)
 - Add a helper to read data from a GEM object page (Imre)
 - VRR/Adaptive Sync Enabling on DP/eDP for TGL+ (Manasi, Ville Aditya)
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Merge tag 'drm-intel-next-2021-01-27' of git://anongit.freedesktop.org/drm/drm-intel into drm-next

- HDCP 2.2 and HDCP 1.4 Gen12 DP MST support (Anshuman)
- Fix DP vswing settings and handling (Imre, Ville)
- Various display code clean-up (Jani, Ville)
- Various display refactoring, including split out of pps, aux, and fdi (Ja\
ni, Dave)
- Add DG1 missing workarounds (Jose)
- Fix display color conversion (Chris, Ville)
- Try to guess PCH type even without ISA bridge (Zhenyu)
- More backlight refactor (Lyude)
- Support two CSC module on gen11 and later (Lee)
- Async flips for all ilk+ platforms (Ville)
- Clear color support for TGL (RK)
- Add a helper to read data from a GEM object page (Imre)
- VRR/Adaptive Sync Enabling on DP/eDP for TGL+ (Manasi, Ville Aditya)

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210127140822.GA711686@intel.com
2021-01-29 17:05:15 +10:00
Lyude Paul 7c553f8b5a drm/dp: Revert "drm/dp: Introduce EDID-based quirks"
This reverts commit 0883ce8146. Originally
these quirks were added because of the issues with using the eDP
backlight interfaces on certain laptop panels, which made it impossible
to properly probe for DPCD backlight support without having a whitelist
for panels that we know have working VESA backlight control interfaces
over DPCD. As well, it should be noted it was impossible to use the
normal sink OUI for recognizing these panels as none of them actually
filled out their OUIs, hence needing to resort to checking EDIDs.

At the time we weren't really sure why certain panels had issues with
DPCD backlight controls, but we eventually figured out that there was a
second interface that these problematic laptop panels actually did work
with and advertise properly: Intel's proprietary backlight interface for
HDR panels. So far the testing we've done hasn't brought any panels to
light that advertise this interface and don't support it properly, which
means we finally have a real solution to this problem.

As a result, we now have no need for the force DPCD backlight quirk, and
furthermore this also removes the need for any kind of EDID quirk
checking in DRM. So, let's just revert it for now since we were the only
driver using this.

v3:
* Rebase
v2:
* Fix indenting error picked up by checkpatch in
  intel_edp_init_connector()

Signed-off-by: Lyude Paul <lyude@redhat.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Cc: thaytan@noraisin.net
Cc: Vasily Khoruzhick <anarsoul@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210114221709.2261452-6-lyude@redhat.com
2021-01-19 12:35:52 -05:00
Lee Jones f3cca4da90 drm/drm_dp_helper: Fix spelling issue and add missing description for 'enable_frl_ready_hpd'
Fixes the following W=1 kernel build warning(s):

 drivers/gpu/drm/drm_dp_helper.c:965: warning: Function parameter or member 'color_spc' not described in 'drm_dp_downstream_rgb_to_ycbcr_conversion'
 drivers/gpu/drm/drm_dp_helper.c:965: warning: Excess function parameter 'colorspc' description in 'drm_dp_downstream_rgb_to_ycbcr_conversion'
 drivers/gpu/drm/drm_dp_helper.c:2678: warning: Function parameter or member 'enable_frl_ready_hpd' not described in 'drm_dp_pcon_frl_prepare'

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210115181601.3432599-14-lee.jones@linaro.org
2021-01-18 15:49:57 +01:00
Daniel Vetter 5beed15e4b Merge tag 'topic/dp-hdmi-2.1-pcon-2020-12-23' of git://anongit.freedesktop.org/drm/drm-intel into drm-next
Add support for DP-HDMI2.1 PCON

From the series cover letter:

This patch series attempts to add support for a DP-HDMI2.1 Protocol
Convertor. The VESA spec for the HDMI2.1 PCON are proposed in Errata
E5 to DisplayPort_v2.0:
https://vesa.org/join-vesamemberships/member-downloads/?action=stamp&fileid=42299
The details are mentioned in:
VESA DP-to-HDMI PCON Specification Standalone Document
https://groups.vesa.org/wg/DP/document/15651

This series starts with adding support for FRL (Fixed Rate Link)
Training between the PCON and HDMI2.1 sink.
As per HDMI2.1 specification, a new data-channel or lane is added in
FRL mode, by repurposing the TMDS clock Channel. Through FRL, higher
bit-rate can be supported, ie. up to 12 Gbps/lane (48 Gbps over 4
lanes).

With these patches, the HDMI2.1 PCON can be configured to achieve FRL
training based on the maximum FRL rate supported by the panel, source
and the PCON.
The approach is to add the support for FRL training between PCON and
HDMI2.1 sink and gradually add other blocks for supporting higher
resolutions and other HDMI2.1 features, that can be supported by pcon
for the sources that do not natively support HDMI2.1.

This is done before the DP Link training between the source and PCON
is started. In case of FRL training is not achieved, the PCON will
work in the regular TMDS mode, without HDMI2.1 feature support.
Any interruption in FRL training between the PCON and HDMI2.1 sink is
notified through IRQ_HPD. On receiving the IRQ_HPD the concerned DPCD
registers are read and FRL training is re-attempted.

Currently, we have tested the FRL training and are able to enable 4K
display with TGL Platform + Realtek PCON RTD2173 with HDMI2.1 supporting
panel.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/87lfdpndkt.fsf@intel.com
2021-01-07 11:02:25 +01:00
Ankit Nautiyal 07c9b8634f drm/dp_helper: Add helpers to configure PCONs RGB-YCbCr Conversion
DP Specification for DP2.0 to HDMI2.1 Pcon specifies support for conversion
of colorspace from RGB to YCbCr.
https://groups.vesa.org/wg/DP/document/previewpdf/15651

This patch adds the relavant registers and helper functions to
get the capability and set the color conversion bits for rgb->ycbcr
conversion through PCON.

v2: As suggested in review comments:
-Fixed bug in the check condition in a drm_helper as reported by
 Dan Carpenter and Kernel test robot. (Dan Carepenter)
-Modified the color-conversion cap helper function, to accommodate
 BT709 and BT2020 colorspace. (Uma Shankar)
-Added spec details for the new cap for color conversion. (Uma Shankar)

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201218103723.30844-8-ankit.k.nautiyal@intel.com
2020-12-22 17:52:50 +02:00
Ankit Nautiyal e2e16da398 drm/dp_helper: Add support for Configuring DSC for HDMI2.1 Pcon
This patch adds registers for getting DSC encoder capability for
a HDMI2.1 PCon. It also addes helper functions to configure
DSC between the PCON and HDMI2.1 sink.

v2: Corrected offset for DSC encoder bpc and minor changes.
Also added helper functions for getting pcon dsc encoder capabilities
as suggested by Uma Shankar.

v3: Only setting the DSC bits for the Protocol Converter control
registers, avoiding overwritining color conversion bits.

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com> (v2)
[Jani: Fixed checkpatch BLOCK_COMMENT_STYLE.]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201218103723.30844-7-ankit.k.nautiyal@intel.com
2020-12-22 17:52:18 +02:00
Swati Sharma 3ce98018c8 drm/dp_helper: Add support for link failure detection
There are specific DPCDs defined for detecting link failures between
the PCON and HDMI sink and check the link status. In case of link
failure, PCON will communicate the same using an IRQ_HPD to source.
HDMI sink would have indicated the same to PCON using SCDC interrupt
mechanism. While source can always read final HDMI sink's status using
I2C over AUX, it is easier and faster to read the PCONs already read
HDMI sink status registers.

This patch adds the DPCDs required for link failure detection and
provide a helper function for printing error count/lane which might
help in debugging the link failure issues.

v2: Addressed comments from Uma Shankar:
-rephrased the commit message, as per the code.
-fixed styling issues
-added documentation for the helper function.

Signed-off-by: Swati Sharma <swati2.sharma@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
[Jani: Fixed checkpatch PARENTHESIS_ALIGNMENT.]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201218103723.30844-6-ankit.k.nautiyal@intel.com
2020-12-22 17:48:58 +02:00
Ankit Nautiyal ce32a6239d drm/dp_helper: Add Helpers for FRL Link Training support for DP-HDMI2.1 PCON
This patch adds support for configuring a PCON device,
connected as a DP branched device to enable FRL Link training
with a HDMI2.1 + sink.

v2: Fixed typos and addressed other review comments from Uma Shankar.
-changed the commit message for better clarity (Uma Shankar)
-removed unnecessary argument supplied to a drm helper function.
-fixed return value for max frl read from pcon.

v3: Removed DPCD 0x3035 for MAX Sink FRL b/w as per new version of spec.

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com> (v2)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201218103723.30844-5-ankit.k.nautiyal@intel.com
2020-12-22 17:48:12 +02:00
Mauro Carvalho Chehab e9d2871f69 drm: fix some kernel-doc markups
Some identifiers have different names between their prototypes
and the kernel-doc markup.

Others need to be fixed, as kernel-doc markups should use this format:
        identifier - description

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/12d4ca26f6843618200529ce5445063734d38c04.1605521731.git.mchehab+huawei@kernel.org
2020-11-16 20:48:20 +01:00
Dave Airlie e047c7be17 Merge tag 'drm-intel-next-queued-2020-11-03' of git://anongit.freedesktop.org/drm/drm-intel into drm-next
drm/i915 features for v5.11

Highlights:
- More DG1 enabling (Lucas, Matt, Aditya, Anshuman, Clinton, Matt, Stuart, Venkata)
- Integer scaling filter support (Pankaj Bharadiya)
- Asynchronous flip support (Karthik)

Generic:
- Fix gen12 forcewake tables (Matt)
- Haswell PCI ID updates (Alexei Podtelezhnikov)

Display:
- ICL+ DSI command mode enabling (Vandita)
- Shutdown displays grafecully on reboot/shutdown (Ville)
- Don't register display debugfs when there is no display (Lucas)
- Fix RKL CDCLK table (Matt)
- Limit EHL/JSL eDP to HBR2 (José)
- Handle incorrectly set (by BIOS) PLLs and DP link rates at probe (Imre)
- Fix mode valid check wrt bpp for "YCbCr 4:2:0 only" modes (Ville)
- State checker and dump fixes (Ville)
- DP AUX backlight updates (Aaron Ma, Sean Paul)
- Add DP LTTPR non-transparent link training mode (Imre)
- PSR2 selective fetch enabling (José)
- VBT updates (José)
- HDCP updates (Ramalingam)

Cleanups and refactoring:
- HPD pin, AUX channel, and Type-C port identifier cleanup (Ville)
- Hotplug and irq refactoring (Ville)
- Better DDI encoder and AUX channel names (Ville)
- Color LUT code cleanups (Ville)
- Combo PHY code cleanups (Ville)
- LSPCON code cleanups (Ville)
- Documentation fixes (Mauro, Chris)

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/87o8kehbaj.fsf@intel.com
2020-11-04 12:17:34 +10:00
Mauro Carvalho Chehab 21a53bbd46 drm/dp: fix kernel-doc warnings at drm_dp_helper.c
As warned by kernel-doc:

	./drivers/gpu/drm/drm_dp_helper.c:385: warning: Function parameter or member 'type' not described in 'drm_dp_downstream_is_type'
	./drivers/gpu/drm/drm_dp_helper.c:886: warning: Function parameter or member 'dev' not described in 'drm_dp_downstream_mode'

Some function parameters weren't documented.

Fixes: 38784f6f88 ("drm/dp: Add helpers to identify downstream facing port types")
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/03c9c8ba3f492aca76e2b4836803219cd9c971cf.1603791716.git.mchehab+huawei@kernel.org
2020-10-27 11:20:36 +01:00
Mauro Carvalho Chehab 444d03badc drm: kernel-doc: document drm_dp_set_subconnector_property() params
Changeset e5b9277328 ("drm: report dp downstream port type as a subconnector property")
added a new function to the kAPI, but didn't add any documentation
for the parameters for drm_dp_set_subconnector_property().

Fixes: e5b9277328 ("drm: report dp downstream port type as a subconnector property")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/0870be85a77bea4ba5cf1715010834289a4e10b1.1603791716.git.mchehab+huawei@kernel.org
2020-10-27 11:20:21 +01:00
Aaron Ma 055f8458d9 drm/i915: Force DPCD backlight mode for BOE 2270 panel
BOE 2270 panel failed to control backlight brightness.
Add it in edid quirks to force using DPCD backlight control.
Then the brightness can be controlled.

Signed-off-by: Aaron Ma <aaron.ma@canonical.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201009085750.88490-2-aaron.ma@canonical.com
2020-10-12 19:37:16 -04:00
Imre Deak 9782f52ab5 drm/dp: Add LTTPR helpers
Add the helpers and register definitions needed to read out the common
and per-PHY LTTPR capabilities and perform link training in the LTTPR
non-transparent mode.

v2:
- Add drm_dp_dpcd_read_phy_link_status() and DP_PHY_LTTPR() here instead
  of adding these to i915. (Ville)
v3:
- Use memmove() to convert LTTPR to DPRX link status format. (Ville)

Cc: dri-devel@lists.freedesktop.org
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Lyude Paul <lyude@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201007170917.1764556-5-imre.deak@intel.com
2020-10-12 15:32:00 +03:00
Mauro Carvalho Chehab 4d658cb778 drm/dp: fix kernel-doc warnings at drm_dp_helper.c
As warned by kernel-doc:

	./drivers/gpu/drm/drm_dp_helper.c:385: warning: Function parameter or member 'type' not described in 'drm_dp_downstream_is_type'
	./drivers/gpu/drm/drm_dp_helper.c:886: warning: Function parameter or member 'dev' not described in 'drm_dp_downstream_mode'

Some function parameters weren't documented.

Fixes: 38784f6f88 ("drm/dp: Add helpers to identify downstream facing port types")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200922175357.42998-2-lyude@redhat.com
2020-09-22 13:56:08 -04:00
Ville Syrjälä 2ef8d0f7de drm/dp: Add helpers for DFP YCbCr 4:2:0 handling
Add helpers to determine whether the DFP supports
YCbCr 4:2:0 passthrough or YCbCr 4:4:4->4:2:0 conversion.

v2: Add kdocs (Lyude)

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200904115354.25336-18-ville.syrjala@linux.intel.com
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2020-09-17 18:39:01 +03:00
Ville Syrjälä 7af655bce2 drm/dp: Add drm_dp_downstream_mode()
The downstream facing port caps in the DPCD can give us a hint
as to what kind of display mode the sink can use if it doesn't
have an EDID. Use that information to pick a suitable mode.

v2: Use Returns: for kdoc (Lyude)
    Add kdocs for drm_display_mode_from_cea_vic() (Lyude)

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200904115354.25336-14-ville.syrjala@linux.intel.com
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2020-09-17 18:33:22 +03:00
Ville Syrjälä 6509ca051a drm/dp: Add drm_dp_downstream_{min,max}_tmds_clock()
Add helpers to get the TMDS clock limits for HDMI/DVI downstream
facing ports.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200904115354.25336-11-ville.syrjala@linux.intel.com
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2020-09-17 18:27:49 +03:00
Ville Syrjälä b770e84311 drm/dp: Redo drm_dp_downstream_max_clock() as drm_dp_downstream_max_dotclock()
We want to differentiate between the DFP dotclock and TMDS clock
limits. Let's convert the current thing to just give us the
dotclock limit.

v2: Use Returns: for kdoc (Lyude)
    Fix up nouveau code too

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200904115354.25336-9-ville.syrjala@linux.intel.com
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2020-09-17 18:25:52 +03:00
Ville Syrjälä 42f2562ca1 drm/dp: Pimp drm_dp_downstream_max_bpc()
Deal with more cases in drm_dp_downstream_max_bpc():
- DPCD 1.0 -> assume 8bpc for non-DP
- DPCD 1.1+ DP (or DP++ with DP sink) -> allow anything
- DPCD 1.1+ TMDS -> check the caps, assume 8bpc if the value is crap
- anything else -> assume 8bpc

v2: Use Returns: for kdoc (Lyude)

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200904115354.25336-8-ville.syrjala@linux.intel.com
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2020-09-17 17:12:15 +03:00
Ville Syrjälä 38784f6f88 drm/dp: Add helpers to identify downstream facing port types
Add a few helpers to let us better identify which kind of DFP
we're dealing with.

v2: Use Returns: for kdoc (Lyude)

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200904115354.25336-7-ville.syrjala@linux.intel.com
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2020-09-17 17:09:32 +03:00
Ville Syrjälä 637f7240f6 drm/dp: Dump downstream facing port caps
It helps when the logs have a dump of the DFP capabilities.

v2: Move the dumping to the new helper

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200904115354.25336-2-ville.syrjala@linux.intel.com
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2020-09-17 17:02:08 +03:00
Dave Airlie 877d8c0743 Merge tag 'topic/nouveau-i915-dp-helpers-and-cleanup-2020-08-31-1' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
UAPI Changes:

None

Cross-subsystem Changes:

* Moves a bunch of miscellaneous DP code from the i915 driver into a set
  of shared DRM DP helpers

Core Changes:

* New DRM DP helpers (see above)

Driver Changes:

* Implements usage of the aforementioned DP helpers in the nouveau
  driver, along with some other various HPD related cleanup for nouveau

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/11e59ebdea7ee4f46803a21fe9b21443d2b9c401.camel@redhat.com
2020-09-09 12:27:13 +10:00
Dave Airlie ce5c207c6b Linux 5.9-rc4
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Merge tag 'v5.9-rc4' into drm-next

Backmerge 5.9-rc4 as there is a nasty qxl conflict
that needs to be resolved.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2020-09-08 14:41:40 +10:00
Lyude Paul b9936121d9 drm/i915/dp: Extract drm_dp_read_dpcd_caps()
Since DP 1.3, it's been possible for DP receivers to specify an
additional set of DPCD capabilities, which can take precedence over the
capabilities reported at DP_DPCD_REV.

Basically any device supporting DP is going to need to read these in an
identical manner, in particular nouveau, so let's go ahead and just move
this code out of i915 into a shared DRM DP helper that we can use in
other drivers.

v2:
* Remove redundant dpcd[DP_DPCD_REV] == 0 check
* Fix drm_dp_dpcd_read() ret checks

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20200826182456.322681-20-lyude@redhat.com
2020-08-31 19:10:09 -04:00
Lyude Paul 4778ff0528 drm/i915/dp: Extract drm_dp_read_sink_count()
And of course, we'll also need to read the sink count from other drivers
as well if we're checking whether or not it's supported. So, let's
extract the code for this into another helper.

v2:
* Fix drm_dp_dpcd_readb() ret check
* Add back comment and move back sink_count assignment in intel_dp_get_dpcd()
v5:
* Change name from drm_dp_get_sink_count() to drm_dp_read_sink_count()
* Also, add "See also:" section to kdocs

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20200826182456.322681-17-lyude@redhat.com
2020-08-31 19:10:09 -04:00
Lyude Paul 693c3ec597 drm/i915/dp: Extract drm_dp_read_sink_count_cap()
Since other drivers are also going to need to be aware of the sink count
in order to do proper dongle detection, we might as well steal i915's
DP_SINK_COUNT helpers and move them into DRM helpers so that other
dirvers can use them as well.

Note that this also starts using intel_dp_has_sink_count() in
intel_dp_detect_dpcd(), which is a functional change.

v5:
* Change name from drm_dp_has_sink_count() to
  drm_dp_read_sink_count_cap()

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20200826182456.322681-16-lyude@redhat.com
2020-08-31 19:10:08 -04:00