This is a quick and low risk fix. Those APIs which
are exposed to other IPs or to support sysfs/hwmon
interfaces or DAL will have lock protection. Meanwhile
no lock protection is enforced for swSMU internal used
APIs. Future optimization is needed.
V2: strip the lock protection for all swSMU internal APIs
Signed-off-by: Evan Quan <evan.quan@amd.com>
Acked-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Acked-by: Feifei Xu <Feifei.Xu@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
This workaround was put in dcn2 DMLv1, and now we need it in DMLv2.
Signed-off-by: Joshua Aberback <joshua.aberback@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
Fix the programming of DCHUBBUB_ARB_REFCYC_PER_TRIP_TO_MEMORY_A.
Was not filled in.
Signed-off-by: Eric Yang <Eric.Yang2@amd.com>
Reviewed-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
We are currently incorrectly processing avoid split at highest
voltage level.
Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Eric Bernstein <Eric.Bernstein@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
In Hybrid Graphics, dcn2_1_soc struct stays alive through PnP.
This causes an issue on dc init where dcn2_1_soc which has been
updated by update_bw_bounding_box gets put into dml->soc.
As update_bw_bounding_box is currently incorrect for dcn2.1,
this makes dml calculations fail due to incorrect parameters,
leading to a crash on PnP.
[How]
Comment out update_bw_bounding_box call for now.
Signed-off-by: Sung Lee <sung.lee@amd.com>
Reviewed-by: Eric Yang <eric.yang2@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[why]
We want to use maximum space on display to show source
[how]
For Centered Mode: Replicate source as many times as possible to use
maximum of display active space add borders.
Signed-off-by: Reza Amini <Reza.Amini@amd.com>
Reviewed-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
Signal is update to EDP when driver disable first encoder. The
following encoder using SIGNAL_TYPE_EDP to handle other
device. When encoder signal is HDMI, driver will detect it is dp
and release phy. It cause hw hang.
[How]
Take signal type from link->connector_signal.
Signed-off-by: Lewis Huang <Lewis.Huang@amd.com>
Reviewed-by: Eric Yang <eric.yang2@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
* Clk Mgr DTO update point did not cover all needed updates, as it included a
check for plane_state which does not exist yet when the updater is called on
driver startup
* This resulted in another update path in the pipe programming sequence, based
on a dppclk update flag
* However, this alternate path allowed for stray DTO updates, some of which would
occur in the wrong order during dppclk lowering and cause underflow
[How]
* Remove plane_state check and use of plane_res.dpp->inst, getting rid
of sequence dependencies (this results in extra dto programming for unused
pipes but that doesn't cause issues and is a small cost)
* Allow DTOs to be updated even if global clock is equal, to account for
edge case exposed by diags tests
* Remove update_dpp_dto call in pipe programming sequence (leave update to
dppclk_control there, as that update is necessary and shouldn't occur in clk
mgr)
* Remove call to optimize_bandwidth when committing state, as it is not needed
and resulted in sporadic underflows even with other fixes in place
Signed-off-by: Noah Abradjian <noah.abradjian@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why&How]
BT.2390 EETF is used for tone mapping/range reduction.
Say display is 0.1 - 500 nits.
The problematic case is when content is 0-400. We apply EETF because
0<0.1 so we need to reduce the range by 0.1.
In the commit, we ignore the bottom range. Most displays map 0 to min and
then have a ramp to 0.1, so sending 0.1 is actually >0.1.
Furthermode, HW that uses 3D LUT also assumes min=0.
Signed-off-by: Krunoslav Kovac <Krunoslav.Kovac@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
SMU does not keep the wm table across S3, S4, need to re-send
the table. Also defer sending the cable to after DCN bave initialized
[How]
Send table at end of init hw
Signed-off-by: Eric Yang <Eric.Yang2@amd.com>
Reviewed-by: Yongqiang Sun <yongqiang.sun@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[why]
A display that supports DRR can never really be considered
"synchronized" with any other display because we can dynamically
enable DRR (i.e. without modeset). this will cause their
relative CRTC positions to drift and lose sync. this will disrupt
features such as MCLK switching that assume and depend on
their permanent alignment (that can only change with modeset)
[how]
check for ignore_msa in stream when considered synchronizability
this ignore_msa is basically actually implemented as "supports drr"
Signed-off-by: Jun Lei <Jun.Lei@amd.com>
Reviewed-by: Yongqiang Sun <yongqiang.sun@amd.com>
Acked-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
When aux engine acquire fails, we missed populating the operation_result
that describes the failure reason.
[How]
Set operation_result to new type:
AUX_CHANNEL_OPERATION_FAILED_ENGINE_ACQUIRE
in the case aux engine acquire has failed.
Signed-off-by: Anthony Koo <Anthony.Koo@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[WHY]
force_single_disp_pipe_split is a debug flag for use on DCN1
but isn't necessary otherwise as DCN2+ splits by default
Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[WHY]
i2c_read is called to differentiate passive DP->HDMI and DP->DVI-D dongles
The call is expected to fail in DVI-D case but pass in HDMI case
Some HDMI dongles have a chance to fail as well, causing misdetection as DVI-D
[HOW]
Retry i2c_read to ensure failed result is valid
Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
The enum value for TRANSMITTER_UNIPHY_G is 9. In resource dc_xx_resource
file structure link_enc_regs[], the TRANSMITTER_UNIPHY_G registers are
initialized at index 6. Due to this mismatch, if monitor is attached to
port using TRANSMITTER_UNIPHY_G then the monitor blanks out.
[How]
add function map_transmitter_id_to_phy_instance() and use the function
to map enum transmitter to link regs.
Signed-off-by: Yogesh Mohan Marimuthu <yogesh.mohanmarimuthu@amd.com>
Reviewed-by: Eric Yang <eric.yang2@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[why]
SLT tests require that diag can drive eDP even if nothing is connected, this is not
typical production use case, so we need to add flag
[how]
add flag, and this flag supercedes "should destroy" logic
Signed-off-by: Jun Lei <Jun.Lei@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Eric Bernstein <Eric.Bernstein@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
These are specific to dcn21 and should not be increased for
reuse on other asics.
Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Chris Park <Chris.Park@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why & How]
vm should be enabled by default for rn to get
right dml.
Signed-off-by: Yongqiang Sun <yongqiang.sun@amd.com>
Reviewed-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[why]
There's a use case for inverted gamma
and it's been confirmed that negative slopes are ok.
[how]
Remove code for blocking non-monotonically increasing gamma
Signed-off-by: Aidan Yang <Aidan.Yang@amd.com>
Reviewed-by: Krunoslav Kovac <Krunoslav.Kovac@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Acked-by: Reza Amini <Reza.Amini@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
NV12 has lower min dcfclk
[How]
Add update in update_bounding_box
Signed-off-by: Alvin Lee <alvin.lee2@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
On some systems, we need to check the dcn version in runtime
system, not in compile time.
[How]
Stub in dcn version parameter to find_first_free_audio
Signed-off-by: Paul Hsieh <paul.hsieh@amd.com>
Reviewed-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[WHY]
DML is incorrectly initialized with 4 pipes on 3 pipe configs
RequiredDPPCLK is halved on unsplit pipe due to an incorrectly handled 3 pipe
case, causing underflow with 2 planes & pipe split (MPO, 8K + 2nd display)
[HOW]
Set correct number of DPP/OTGs for dml init to generate correct DPP topology
Double RequiredDPPCLK after clock is halved for pipe split
and find_secondary_pipe fails to fix underflow
Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Reviewed-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Chris Park <Chris.Park@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This value will be needed by dml and therefore should be externally
accessible.
Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Nevenko Stupar <Nevenko.Stupar@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
One of odm variables was not initialized in dml.
Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Chris Park <Chris.Park@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Acked-by: Tony Cheng <Tony.Cheng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Split a large function into smaller, reusable chunks.
Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Nevenko Stupar <Nevenko.Stupar@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
In diags environment we are not programming the DPP DTO
correctly.
[How]
Populate the dpp refclk in dccg so it can be used to correctly
program DPP DTO.
Signed-off-by: Anthony Koo <Anthony.Koo@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
PSR (Panel Self-Refresh) is a power-saving feature for eDP panels.
The feature has support in DMCU (Display MicroController Unit).
DMCU/driver communication is implemented in DC.
DM can use existing DC PSR interface to use PSR feature.
[How]
- Read psr caps via dpcd
- Send vsc infoframe if panel supports psr
- Disable psr before h/w programming (FULL_UPDATE)
- Enable psr after h/w programming
- Disable psr for fb console
Signed-off-by: Roman Li <Roman.Li@amd.com>
Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
For upcoming PSR stupport it's useful to have debug entry
to verify psr state.
[How]
- Enable psr dc api for Linux
- Add psr_state file to eDP connector debugfs
usage e.g.: cat /sys/kernel/debug/dri/0/DP-1/psr_state
Signed-off-by: Roman Li <Roman.Li@amd.com>
Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Commit hints are unnecessary after front end programming redesign.
Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Eric Bernstein <Eric.Bernstein@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
For loop below the assert already checks for the number of instances to
create. ASSERT is meaningless and causing spam.
[How]
dd
Signed-off-by: Jordan Lazare <Jordan.Lazare@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[why]
Optimized gamma22 assumes fixed point distribution which is not true
for eetf true.
[how]
Use long calculation for eetf.
Signed-off-by: Aidan Yang <Aidan.Yang@amd.com>
Reviewed-by: Krunoslav Kovac <Krunoslav.Kovac@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Acked-by: Reza Amini <Reza.Amini@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
System hang during S0i3 if DP only connected due to clk is disabled when
doing link training.
During S0i3, clk is disabled while the clk state is updated when ini_hw
called, and at the moment clk is still disabled which indicating a wrong
state for next time trying to enable clk.
[How]
Add an unknown state and initialize it during int_hw, make sure enable clk
command be sent to smu.
Signed-off-by: Yongqiang Sun <yongqiang.sun@amd.com>
Reviewed-by: Eric Yang <eric.yang2@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[why]
Hard to determine if pipe combine is done with MPC or ODM
[how]
Add new visual confirm type, this will mark each MPCC tree
with a different color
Signed-off-by: Jun Lei <Jun.Lei@amd.com>
Reviewed-by: Yongqiang Sun <yongqiang.sun@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Jun Lei <Jun.Lei@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
While setting hdmi_vic, hv_frame.vic is not initialized and might
assign a wrong value to hdmi_vic. Cause to send out VSIF with
abnormal value.
[How]
Initialize hv_frame and avi_frame
Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
We're leaking memory by not freeing the gamma used to calculate the
transfer function for legacy gamma.
[How]
Release the gamma after we're done with it.
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
This patch is for fixing Navi14 HDMI display pink screen issue.
[How]
Call stream->link->link_enc->funcs->setup twice. This is setting
the DIG_MODE to the correct value after having been overridden by
the call to transmitter control.
Signed-off-by: Zhan Liu <zhan.liu@amd.com>
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm-next-5.5-2019-10-09:
amdgpu:
- Additional RAS enablement for vega20
- RAS page retirement and bad page storage in EEPROM
- No GPU reset with unrecoverable RAS errors
- Reserve vram for page tables rather than trying to evict
- Fix issues with GPU reset and xgmi hives
- DC i2c over aux fixes
- Direct submission for clears, PTE/PDE updates
- Improvements to help support recoverable GPU page faults
- Silence harmless SAD block messages
- Clean up code for creating a bo at a fixed location
- Initial DC HDCP support
- Lots of documentation fixes
- GPU reset for renoir
- Add IH clockgating support for soc15 asics
- Powerplay improvements
- DC MST cleanups
- Add support for MSI-X
- Misc cleanups and bug fixes
amdkfd:
- Query KFD device info by asic type rather than pci ids
- Add navi14 support
- Add renoir support
- Add navi12 support
- gfx10 trap handler improvements
- pasid cleanups
- Check against device cgroup
ttm:
- Return -EBUSY with pipelining with no_gpu_wait
radeon:
- Silence harmless SAD block messages
device_cgroup:
- Export devcgroup_check_permission
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191010041713.3412-1-alexander.deucher@amd.com
This allows blocking for BOs to become available
in the memory management.
Amdgpu is doing this for quite a while now during CS. Now
apply the new behavior to all drivers using TTM.
Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Thomas Hellstrom <thellstrom@vmware.com>
Link: https://patchwork.freedesktop.org/patch/332878/
Finally! For a very long time, our MST helpers have had one very
annoying issue: They don't know how to reprobe the topology state when
coming out of suspend. This means that if a user has a machine connected
to an MST topology and decides to suspend their machine, we lose all
topology changes that happened during that period. That can be a big
problem if the machine was connected to a different topology on the same
port before resuming, as we won't bother reprobing any of the ports and
likely cause the user's monitors not to come back up as expected.
So, we start fixing this by teaching our MST helpers how to reprobe the
link addresses of each connected topology when resuming. As it turns
out, the behavior that we want here is identical to the behavior we want
when initially probing a newly connected MST topology, with a couple of
important differences:
- We need to be more careful about handling the potential races between
events from the MST hub that could change the topology state as we're
performing the link address reprobe
- We need to be more careful about handling unlikely state changes on
ports - such as an input port turning into an output port, something
that would be far more likely to happen in situations like the MST hub
we're connected to being changed while we're suspend
Both of which have been solved by previous commits. That leaves one
requirement:
- We need to prune any MST ports in our in-memory topology state that
were present when suspending, but have not appeared in the post-resume
link address response from their parent branch device
Which we can now handle in this commit by modifying
drm_dp_send_link_address(). We then introduce suspend/resume reprobing
by introducing drm_dp_mst_topology_mgr_invalidate_mstb(), which we call
in drm_dp_mst_topology_mgr_suspend() to traverse the in-memory topology
state to indicate that each mstb needs it's link address resent and PBN
resources reprobed.
On resume, we start back up &mgr->work and have it reprobe the topology
in the same way we would on a hotplug, removing any leftover ports that
no longer appear in the topology state.
Changes since v4:
* Split indenting changes in drm_dp_mst_topology_mgr_resume() into a
separate patch
* Only fire hotplugs when something has actually changed after a link
address probe
* Don't try to change port->connector at all on ports, just throw out
ports that need their connectors removed to make things easier.
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Sean Paul <sean@poorly.run>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191022023641.8026-14-lyude@redhat.com
Since we're going to be reprobing the entire topology state on resume
now using sideband transactions, we need to ensure that we actually have
short HPD irqs enabled before calling drm_dp_mst_topology_mgr_resume().
So, do that.
Changes since v3:
* Fix typo in comments
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191022023641.8026-13-lyude@redhat.com
Currently, every single piece of code in amdgpu that loops through
connectors does it incorrectly and doesn't use the proper list iteration
helpers, drm_connector_list_iter_begin() and
drm_connector_list_iter_end(). Yeesh.
So, do that.
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191022023641.8026-12-lyude@redhat.com
This is a complicated one. Essentially, there's currently a problem in the MST
core that hasn't really caused any issues that we're aware of (emphasis on "that
we're aware of"): locking.
When we go through and probe the link addresses and path resources in a
topology, we hold no locks when updating ports with said information. The
members I'm referring to in particular are:
- ldps
- ddps
- mcs
- pdt
- dpcd_rev
- num_sdp_streams
- num_sdp_stream_sinks
- available_pbn
- input
- connector
Now that we're handling UP requests asynchronously and will be using some of
the struct members mentioned above in atomic modesetting in the future for
features such as PBN validation, this is going to become a lot more important.
As well, the next few commits that prepare us for and introduce suspend/resume
reprobing will also need clear locking in order to prevent from additional
racing hilarities that we never could have hit in the past.
So, let's solve this issue by using &mgr->base.lock, the modesetting
lock which currently only protects &mgr->base.state. This works
perfectly because it allows us to avoid blocking connection_mutex
unnecessarily, and we can grab this in connector detection paths since
it's a ww mutex. We start by having drm_dp_mst_handle_up_req() hold this
when updating ports. For drm_dp_mst_handle_link_address_port() things
are a bit more complicated. As I've learned the hard way, we can grab
&mgr->lock.base for everything except for port->connector. See, our
normal driver probing paths end up generating this rather obvious
lockdep chain:
&drm->mode_config.mutex
-> crtc_ww_class_mutex/crtc_ww_class_acquire
-> &connector->mutex
However, sysfs grabs &drm->mode_config.mutex in order to protect itself
from connector state changing under it. Because this entails grabbing
kn->count, e.g. the lock that the kernel provides for protecting sysfs
contexts, we end up grabbing kn->count followed by
&drm->mode_config.mutex. This ends up creating an extremely rude chain:
&kn->count
-> &drm->mode_config.mutex
-> crtc_ww_class_mutex/crtc_ww_class_acquire
-> &connector->mutex
I mean, look at that thing! It's just evil!!! This gross thing ends up
making any calls to drm_connector_register()/drm_connector_unregister()
impossible when holding any kind of modesetting lock. This is annoying
because ideally, we always want to ensure that
drm_dp_mst_port->connector never changes when doing an atomic commit or
check that would affect the atomic topology state so that it can
reliably and easily be used from future DRM DP MST helpers to assist
with tasks such as scanning through the current VCPI allocations and
adding connectors which need to have their allocations updated in
response to a bandwidth change or the like.
Being able to hold &mgr->base.lock throughout the entire link probe
process would have been _great_, since we could prevent userspace from
ever seeing any states in-between individual port changes and as a
result likely end up with a much faster probe and more consistent
results from said probes. But without some rework of how we handle
connector probing in sysfs it's not at all currently possible. In the
future, maybe we can try using the sysfs locks to protect updates to
connector probing state and fix this mess.
So for now, to protect everything other than port->connector under
&mgr->base.lock and ensure that we still have the guarantee that atomic
check/commit contexts will never see port->connector change we use a
silly trick. See: port->connector only needs to change in order to
ensure that input ports (see the MST spec) never have a ghost connector
associated with them. But, there's nothing stopping us from simply
throwing the entire port out and creating a new one in order to maintain
that requirement while still keeping port->connector consistent across
the lifetime of the port in atomic check/commit contexts. For all
intended purposes this works fine, as we validate ports in any contexts
we care about before using them and as such will end up reporting the
connector as disconnected until it's port's destruction finalizes. So,
we just do that in cases where we detect port->input has transitioned
from true->false. We don't need to worry about the other direction,
since a port without a connector isn't visible to userspace and as such
doesn't need to be protected by &mgr->base.lock until we finish
registering a connector for it.
For updating members of drm_dp_mst_port other than port->connector, we
simply grab &mgr->base.lock in drm_dp_mst_link_probe_work() for already
registered ports, update said members and drop the lock before
potentially registering a connector and probing the link address of it's
children.
Finally, we modify drm_dp_mst_detect_port() to take a modesetting lock
acquisition context in order to acquire &mgr->base.lock under
&connection_mutex and convert all it's users over to using the
.detect_ctx probe hooks.
With that, we finally have well defined locking.
Changes since v4:
* Get rid of port->mutex, stop using connection_mutex and just use our own
modesetting lock - mgr->base.lock. Also, add a probe_lock that comes
before this patch.
* Just throw out ports that get changed from an output to an input, and
replace them with new ports. This lets us ensure that modesetting
contexts never see port->connector go from having a connector to being
NULL.
* Write an extremely detailed explanation of what problems this is
trying to fix, since there's a _lot_ of context here and I honestly
forgot some of it myself a couple times.
* Don't grab mgr->lock when reading port->mstb in
drm_dp_mst_handle_link_address_port(). It's not needed.
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Sean Paul <sean@poorly.run>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191022023641.8026-7-lyude@redhat.com
Fix sparse warning:
drivers/gpu/drm/amd/amdgpu/../display/dc/core/dc_link.c:746:6:
warning: symbol 'dc_link_detect_helper' was not declared. Should it be static?
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Reviewed-by: Roman Li <Roman.Li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
