Commit graph

171 commits

Author SHA1 Message Date
Alex Deucher
9edb435aed drm/dp_mst: fix documentation of drm_dp_mst_add_affected_dsc_crtcs
the parameter is the mst manager, not the port.

Reviewed-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2020-01-09 18:07:48 -05:00
David (Dingchen) Zhang
c908b1c4bb drm: add dp helper to initialize remote aux channel.
[why]
We need to minimally initialize the remote aux channel, e.g. the
crc work struct of remote aux to dump the sink's DPRX CRCs in MST
setup.

[how]
Add helper that only initializes the crc work struct of the remote
aux, hooke crc work queue to 'drm_dp_aux_crc_work'. Then call this
helper in DP MST port initialization.
This, plus David Francis' patch [1], fix the issue of MST remote
aux DPCD CRCs read.

[1] https://patchwork.kernel.org/patch/11217941/

Cc: Leo Li <sunpeng.li@amd.com>
Cc: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: David (Dingchen) Zhang <dingchen.zhang@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2020-01-09 18:07:48 -05:00
Mikita Lipski
8ec046716c drm/dp_mst: Add helper to trigger modeset on affected DSC MST CRTCs
[why]
Whenever a connector on an MST network is changed or
undergoes a modeset, the DSC configs for each stream on that
topology will be recalculated. This can change their required
bandwidth, requiring a full reprogramming, as though a modeset
was performed, even if that stream did not change timing.

[how]
Adding helper to trigger modesets on MST DSC connectors
by setting mode_changed flag on CRTCs in the same topology
as affected connector

v2: use drm_dp_mst_dsc_aux_for_port function to verify
if the port is DSC capable

v3: - added _must_check attribute
    - removed topology manager check
    - fix typos and indentations

Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2020-01-09 18:07:48 -05:00
Mikita Lipski
9e5b959036 drm/dp_mst: Rename drm_dp_mst_atomic_check_topology_state
[why]
drm_dp_mst_atomic_check_topology_state() should be renamed
to reflect more specific type of check. Since it is verifying
payload allocation limit it should be renamed into
drm_dp_mst_atomic_check_vcpi_alloc_limit()

Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2020-01-09 18:07:47 -05:00
Mikita Lipski
cd82d82cbc drm/dp_mst: Add branch bandwidth validation to MST atomic check
[why]
Adding PBN attribute to drm_dp_vcpi_allocation structure to
keep track of how much bandwidth each Port requires.
Adding drm_dp_mst_atomic_check_bw_limit to verify that
state's bandwidth needs doesn't exceed available bandwidth.
The funtion is called in drm_dp_mst_atomic_check after
drm_dp_mst_atomic_check_topology_state to fully verify that
the proposed topology is supported.

v2: Fixing some typos and indenting
v3: Return correct error enums if no bw space available

Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2020-01-09 18:07:47 -05:00
Mikita Lipski
8afb7e6afa drm/dp_mst: Add DSC enablement helpers to DRM
Adding a helper function to be called by
drivers outside of DRM to enable DSC on
the MST ports.

Function is called to recalculate VCPI allocation
if DSC is enabled and raise the DSC flag to enable.
In case of disabling DSC the flag is set to false
and recalculation of VCPI slots is expected to be done
in encoder's atomic_check.

v2: squash separate functions into one and call it per
port
v3: Fix comment typos

Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2020-01-09 18:07:47 -05:00
Mikita Lipski
1c6c1cb5af drm/dp_mst: Manually overwrite PBN divider for calculating timeslots
[why]
For DSC case we cannot use topology manager's PBN divider
variable. The default divider does not take FEC into account.
Therefore the driver has to calculate its own divider based
on the link rate and lane count its handling, as it is hw specific.

[how]
Pass pbn_div as an argument, which is used if its more than
zero, otherwise default topology manager's pbn_div will be used.

Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2020-01-09 18:07:47 -05:00
Mikita Lipski
5b03f9d868 drm/dp_mst: Add new quirk for Synaptics MST hubs
Synaptics DP1.4 hubs (BRANCH_ID 0x90CC24) do not
support virtual DPCD registers, but do support DSC.
The DSC caps can be read from the physical aux,
like in SST DSC. These hubs have many different
DEVICE_IDs.  Add a new quirk to detect this case.

v2: Fix error when checking return of drm_dp_read_desc

Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: David Francis <David.Francis@amd.com>
Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2020-01-09 18:07:46 -05:00
David Francis
c2bc1b6eab drm/dp_mst: Add helpers for MST DSC and virtual DPCD aux
Add drm_dp_mst_dsc_aux_for_port. To enable DSC, the DSC_ENABLED
register might have to be written on the leaf port's DPCD,
its parent's DPCD, or the MST manager's DPCD. This function
finds the correct aux for the job.

As part of this, add drm_dp_mst_is_virtual_dpcd. Virtual DPCD
is a DP feature new in DP v1.4, which exposes certain DPCD
registers on virtual ports.

v2: Remember to unlock mutex on all paths
v3: Refactor to match coding style and increase brevity
v4: - Check DSC capable MST sink connected directly to the device.
    - Check branch's port_parent to be set

Cc: Lyude Paul <lyude@redhat.com>
Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Signed-off-by: David Francis <David.Francis@amd.com>
Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2020-01-09 18:07:46 -05:00
David Francis
b1dee9a716 drm/dp_mst: Fill branch->num_ports
This field on drm_dp_mst_branch was never filled

It is initialized to zero when the port is kzallocced.
When a port is added to the list, increment num_ports,
and when a port is removed from the list, decrement num_ports.

v2: remember to decrement on port removal
v3: don't explicitly init to 0
v4: move decrement of num_ports to unlink_port function

Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: David Francis <David.Francis@amd.com>
Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2020-01-09 18:07:46 -05:00
David Francis
a3c2b0ffc0 drm/dp_mst: Parse FEC capability on MST ports
As of DP1.4, ENUM_PATH_RESOURCES returns a bit indicating
if FEC can be supported up to that point in the MST network.

The bit is the first byte of the ENUM_PATH_RESOURCES ack reply,
bottom-most bit (refer to section 2.11.9.4 of DP standard,
v1.4)

That value is needed for FEC and DSC support

Store it on drm_dp_mst_port

Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: David Francis <David.Francis@amd.com>
Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2020-01-09 18:07:46 -05:00
David Francis
dc48529fb1 drm/dp_mst: Add PBN calculation for DSC modes
With DSC, bpp can be fractional in multiples of 1/16.

Change drm_dp_calc_pbn_mode to reflect this, adding a new
parameter bool dsc. When this parameter is true, treat the
bpp parameter as having units not of bits per pixel, but
1/16 of a bit per pixel

v2: Don't add separate function for this
v3: In the equation divide bpp by 16 as it is expected
not to leave any remainder
v4: Added DSC test parameters for selftest

Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: David Francis <David.Francis@amd.com>
Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2020-01-09 18:07:46 -05:00
Daniel Vetter
6c56e8adc0 drm-misc-next for v5.6:
UAPI Changes:
 - Add support for DMA-BUF HEAPS.
 
 Cross-subsystem Changes:
 - mipi dsi definition updates, pulled into drm-intel as well.
 - Add lockdep annotations for dma_resv vs mmap_sem and fs_reclaim.
 - Remove support for dma-buf kmap/kunmap.
 - Constify fb_ops in all fbdev drivers, including drm drivers and drm-core, and media as well.
 
 Core Changes:
 - Small cleanups to ttm.
 - Fix SCDC definition.
 - Assorted cleanups to core.
 - Add todo to remove load/unload hooks, and use generic fbdev emulation.
 - Assorted documentation updates.
 - Use blocking ww lock in ttm fault handler.
 - Remove drm_fb_helper_fbdev_setup/teardown.
 - Warning fixes with W=1 for atomic.
 - Use drm_debug_enabled() instead of drm_debug flag testing in various drivers.
 - Fallback to nontiled mode in fbdev emulation when not all tiles are present. (Later on reverted)
 - Various kconfig indentation fixes in core and drivers.
 - Fix freeing transactions in dp-mst correctly.
 - Sean Paul is steping down as core maintainer. :-(
 - Add lockdep annotations for atomic locks vs dma-resv.
 - Prevent use-after-free for a bad job in drm_scheduler.
 - Fill out all block sizes in the P01x and P210 definitions.
 - Avoid division by zero in drm/rect, and fix bounds.
 - Add drm/rect selftests.
 - Add aspect ratio and alternate clocks for HDMI 4k modes.
 - Add todo for drm_framebuffer_funcs and fb_create cleanup.
 - Drop DRM_AUTH for prime import/export ioctls.
 - Clear DP-MST payload id tables downstream when initializating.
 - Fix for DSC throughput definition.
 - Add extra FEC definitions.
 - Fix fake offset in drm_gem_object_funs.mmap.
 - Stop using encoder->bridge in core directly
 - Handle bridge chaining slightly better.
 - Add backlight support to drm/panel, and use it in many panel drivers.
 - Increase max number of y420 modes from 128 to 256, as preparation to add the new modes.
 
 Driver Changes:
 - Small fixes all over.
 - Fix documentation in vkms.
 - Fix mmap_sem vs dma_resv in nouveau.
 - Small cleanup in komeda.
 - Add page flip support in gma500 for psb/cdv.
 - Add ddc symlink in the connector sysfs directory for many drivers.
 - Add support for analogic an6345, and fix small bugs in it.
 - Add atomic modesetting support to ast.
 - Fix radeon fault handler VMA race.
 - Switch udl to use generic shmem helpers.
 - Unconditional vblank handling for mcde.
 - Miscellaneous fixes to mcde.
 - Tweak debug output from komeda using debugfs.
 - Add gamma and color transform support to komeda for DOU-IPS.
 - Add support for sony acx424AKP panel.
 - Various small cleanups to gma500.
 - Use generic fbdev emulation in udl, and replace udl_framebuffer with generic implementation.
 - Add support for Logic PD Type 28 panel.
 - Use drm_panel_* wrapper functions in exynos/tegra/msm.
 - Add devicetree bindings for generic DSI panels.
 - Don't include drm_pci.h directly in many drivers.
 - Add support for begin/end_cpu_access in udmabuf.
 - Stop using drm_get_pci_dev in gma500 and mga200.
 - Fixes to UDL damage handling, and use dma_buf_begin/end_cpu_access.
 - Add devfreq thermal support to panfrost.
 - Fix hotplug with daisy chained monitors by removing VCPI when disabling topology manager.
 - meson: Add support for OSD1 plane AFBC commit.
 - Stop displaying garbage when toggling ast primary plane on/off.
 - More cleanups and fixes to UDL.
 - Add D32 suport to komeda.
 - Remove globle copy of drm_dev in gma500.
 - Add support for Boe Himax8279d MIPI-DSI LCD panel.
 - Add support for ingenic JZ4770 panel.
 - Small null pointer deference fix in ingenic.
 - Remove support for the special tfp420 driver, as there is a generic way to do it.
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Merge tag 'drm-misc-next-2019-12-16' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

drm-misc-next for v5.6:

UAPI Changes:
- Add support for DMA-BUF HEAPS.

Cross-subsystem Changes:
- mipi dsi definition updates, pulled into drm-intel as well.
- Add lockdep annotations for dma_resv vs mmap_sem and fs_reclaim.
- Remove support for dma-buf kmap/kunmap.
- Constify fb_ops in all fbdev drivers, including drm drivers and drm-core, and media as well.

Core Changes:
- Small cleanups to ttm.
- Fix SCDC definition.
- Assorted cleanups to core.
- Add todo to remove load/unload hooks, and use generic fbdev emulation.
- Assorted documentation updates.
- Use blocking ww lock in ttm fault handler.
- Remove drm_fb_helper_fbdev_setup/teardown.
- Warning fixes with W=1 for atomic.
- Use drm_debug_enabled() instead of drm_debug flag testing in various drivers.
- Fallback to nontiled mode in fbdev emulation when not all tiles are present. (Later on reverted)
- Various kconfig indentation fixes in core and drivers.
- Fix freeing transactions in dp-mst correctly.
- Sean Paul is steping down as core maintainer. :-(
- Add lockdep annotations for atomic locks vs dma-resv.
- Prevent use-after-free for a bad job in drm_scheduler.
- Fill out all block sizes in the P01x and P210 definitions.
- Avoid division by zero in drm/rect, and fix bounds.
- Add drm/rect selftests.
- Add aspect ratio and alternate clocks for HDMI 4k modes.
- Add todo for drm_framebuffer_funcs and fb_create cleanup.
- Drop DRM_AUTH for prime import/export ioctls.
- Clear DP-MST payload id tables downstream when initializating.
- Fix for DSC throughput definition.
- Add extra FEC definitions.
- Fix fake offset in drm_gem_object_funs.mmap.
- Stop using encoder->bridge in core directly
- Handle bridge chaining slightly better.
- Add backlight support to drm/panel, and use it in many panel drivers.
- Increase max number of y420 modes from 128 to 256, as preparation to add the new modes.

Driver Changes:
- Small fixes all over.
- Fix documentation in vkms.
- Fix mmap_sem vs dma_resv in nouveau.
- Small cleanup in komeda.
- Add page flip support in gma500 for psb/cdv.
- Add ddc symlink in the connector sysfs directory for many drivers.
- Add support for analogic an6345, and fix small bugs in it.
- Add atomic modesetting support to ast.
- Fix radeon fault handler VMA race.
- Switch udl to use generic shmem helpers.
- Unconditional vblank handling for mcde.
- Miscellaneous fixes to mcde.
- Tweak debug output from komeda using debugfs.
- Add gamma and color transform support to komeda for DOU-IPS.
- Add support for sony acx424AKP panel.
- Various small cleanups to gma500.
- Use generic fbdev emulation in udl, and replace udl_framebuffer with generic implementation.
- Add support for Logic PD Type 28 panel.
- Use drm_panel_* wrapper functions in exynos/tegra/msm.
- Add devicetree bindings for generic DSI panels.
- Don't include drm_pci.h directly in many drivers.
- Add support for begin/end_cpu_access in udmabuf.
- Stop using drm_get_pci_dev in gma500 and mga200.
- Fixes to UDL damage handling, and use dma_buf_begin/end_cpu_access.
- Add devfreq thermal support to panfrost.
- Fix hotplug with daisy chained monitors by removing VCPI when disabling topology manager.
- meson: Add support for OSD1 plane AFBC commit.
- Stop displaying garbage when toggling ast primary plane on/off.
- More cleanups and fixes to UDL.
- Add D32 suport to komeda.
- Remove globle copy of drm_dev in gma500.
- Add support for Boe Himax8279d MIPI-DSI LCD panel.
- Add support for ingenic JZ4770 panel.
- Small null pointer deference fix in ingenic.
- Remove support for the special tfp420 driver, as there is a generic way to do it.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ba73535a-9334-5302-2e1f-5208bd7390bd@linux.intel.com
2019-12-17 13:57:54 +01:00
Wayne Lin
64e62bdf04 drm/dp_mst: Remove VCPI while disabling topology mgr
[Why]

This patch is trying to address the issue observed when hotplug DP
daisy chain monitors.

e.g.
src-mstb-mstb-sst -> src (unplug) mstb-mstb-sst -> src-mstb-mstb-sst
(plug in again)

Once unplug a DP MST capable device, driver will call
drm_dp_mst_topology_mgr_set_mst() to disable MST. In this function,
it cleans data of topology manager while disabling mst_state. However,
it doesn't clean up the proposed_vcpis of topology manager.
If proposed_vcpi is not reset, once plug in MST daisy chain monitors
later, code will fail at checking port validation while trying to
allocate payloads.

When MST capable device is plugged in again and try to allocate
payloads by calling drm_dp_update_payload_part1(), this
function will iterate over all proposed virtual channels to see if
any proposed VCPI's num_slots is greater than 0. If any proposed
VCPI's num_slots is greater than 0 and the port which the
specific virtual channel directed to is not in the topology, code then
fails at the port validation. Since there are stale VCPI allocations
from the previous topology enablement in proposed_vcpi[], code will fail
at port validation and reurn EINVAL.

[How]

Clean up the data of stale proposed_vcpi[] and reset mgr->proposed_vcpis
to NULL while disabling mst in drm_dp_mst_topology_mgr_set_mst().

Changes since v1:
*Add on more details in commit message to describe the issue which the
patch is trying to fix

Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
[added cc to stable]
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191205090043.7580-1-Wayne.Lin@amd.com
Cc: <stable@vger.kernel.org> # v3.17+
2019-12-06 14:51:12 -05:00
Sean Paul
f79489074c drm/dp_mst: Clear all payload id tables downstream when initializing
It seems that on certain MST hubs, namely the CableMatters USB-C 2x DP
hub, using the DP_PAYLOAD_ALLOCATE_SET and DP_PAYLOAD_TABLE_UPDATE_STATUS
register ranges to clear any pre-existing payload allocations on the hub isn't
always enough to reset things if the source device has been reset unexpectedly.

Or at least, that's the current running theory. The precise behavior appears to
be that when the source device gets reset unexpectedly, the hub begins reporting
an available_pbn value of 0 for all of its ports. This is a bit inconsistent
with the our theory, since this seems to happen even if previously set PBN
allocations should have resulted in a non-zero available_pbn value. So, it's
possible that something else may be going on here.

Strangely though, sending a CLEAR_PAYLOAD_ID_TABLE broadcast request when
initializing the MST topology seems to bring things into working order and make
available_pbn work again. Since this is a pretty safe solution, let's go ahead
and implement it.

Changes since v1:
* Change indenting on drm_dp_send_clear_payload_id_table() prototype
* Remove some braces in drm_dp_send_clear_payload_id_table()
* Reorganize some variable declarations in drm_dp_send_clear_payload_id_table()
* Don't forget to handle DP_CLEAR_PAYLOAD_ID_TABLE in
  drm_dp_sideband_parse_reply()
* Move drm_dp_send_clear_payload_id_table() call into
  drm_dp_mst_link_probe_work(), since we can't send sideband messages
  while under lock in drm_dp_mst_topology_mgr_set_mst()
* Change commit message

Acked-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190829000944.20722-1-lyude@redhat.com
2019-12-05 13:13:46 -05:00
Wayne Lin
e5a6ca27eb drm/dp_mst: Correct the bug in drm_dp_update_payload_part1()
[Why]
If the payload_state is DP_PAYLOAD_DELETE_LOCAL in series, current
code doesn't delete the payload at current index and just move the
index to next one after shuffling payloads.

[How]
Drop the i++ increasing part in for loop head and decide whether
to increase the index or not according to payload_state of current
payload.

Changes since v1:
* Refine the code to have it easy reading
* Amend the commit message to meet the way code is modified now.

Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Fixes: 706246c761 ("drm/dp_mst: Refactor drm_dp_update_payload_part1()")
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Juston Li <juston.li@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.1+
[Added cc for stable]
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191203042423.5961-1-Wayne.Lin@amd.com
2019-12-04 15:31:16 -05:00
Colin Ian King
2c8bc91488 drm/dp_mst: fix multiple frees of tx->bytes
Currently tx->bytes is being freed r->num_transactions number of
times because tx is not being set correctly. Fix this by setting
tx to &r->transactions[i] so that the correct objects are being
freed on each loop iteration.

Addresses-Coverity: ("Double free")
Fixes: 2f015ec6ea ("drm/dp_mst: Add sideband down request tracing + selftests")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191120173509.347490-1-colin.king@canonical.com
2019-11-20 14:16:15 -05:00
Sean Paul
b149cbfeec drm/mst: Fix up u64 division
Change rem_nsec to u32 since that's what do_div returns, this avoids the
u64 divide in the drm_print args.

Changes in v2:
- Instead of doing do_div in drm_print, make rem_nsec u32 (Ville)

Link to v1: https://patchwork.freedesktop.org/patch/msgid/20191106173622.15573-1-sean@poorly.run

Fixes: 12a280c728 ("drm/dp_mst: Add topology ref history tracking for debugging")
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>
Cc: Sean Paul <sean@poorly.run>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191106194121.164458-1-sean@poorly.run
2019-11-06 15:20:37 -05:00
Chenwandun
68acde7629 drm/dp_mst: fix gcc compile error
drivers/gpu/drm/drm_dp_mst_topology.c: In function __topology_ref_save:
drivers/gpu/drm/drm_dp_mst_topology.c:1424:6: error: implicit declaration of function stack_trace_save; did you mean stack_depot_save? [-Werror=implicit-function-declaration]
  n = stack_trace_save(stack_entries, ARRAY_SIZE(stack_entries), 1);
      ^~~~~~~~~~~~~~~~
      stack_depot_save
drivers/gpu/drm/drm_dp_mst_topology.c: In function __dump_topology_ref_history:
drivers/gpu/drm/drm_dp_mst_topology.c:1513:3: error: implicit declaration of function stack_trace_snprint; did you mean acpi_trace_point? [-Werror=implicit-function-declaration]
   stack_trace_snprint(buf, PAGE_SIZE, entries, nr_entries, 4);
   ^~~~~~~~~~~~~~~~~~~
   acpi_trace_point

stack_trace_save and stack_trace_snprint are declared in <linux/stacktrace.h>,
so there is need to include it, and <linux/stackdepot.h> is already included
by practices, so just replace <linux/stackdepot.h> by <linux/stacktrace.h>.

Signed-off-by: Chenwandun <chenwandun@huawei.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1572515029-42087-1-git-send-email-chenwandun@huawei.com
2019-11-06 05:45:29 +10:00
Dave Airlie
57c2af791b Merge tag 'topic/mst-suspend-resume-reprobe-2019-10-29-2' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
UAPI Changes:

Cross-subsystem Changes:

Core Changes:
* Handle UP requests asynchronously in the DP MST helpers, fixing
  hotplug notifications and allowing us to implement suspend/resume
  reprobing
* Add basic suspend/resume reprobing to the DP MST helpers
* Improve locking for link address reprobing and connection status
  request handling in the DP MST helpers
* Miscellaneous refactoring in the DP MST helpers
* Add a Kconfig option to the DP MST helpers to enable tracking of
  gets/puts for topology references for debugging purposes

Driver Changes:
* nouveau: Resume hotplug interrupts earlier, so that sideband
  messages may be transmitted during resume and thus allow
  suspend/resume reprobing for DP MST to work
* nouveau: Avoid grabbing runtime PM references when handling short DP
  pulses, so that handling sideband messages in resume codepaths with the
  DP MST helpers doesn't deadlock us
* i915, nouveau, amdgpu, radeon: Use detect_ctx for probing MST
  connectors, so that we can grab the topology manager's atomic lock

Note: there's some amdgpu patches that I didn't realize were pushed
upstream already when creating this topic branch. When they fail to
apply, you can just ignore and skip them.

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

From: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/a74c6446bc960190d195a751cb6d8a00a98f3974.camel@redhat.com
2019-10-30 09:51:03 +10:00
Lyude Paul
12a280c728 drm/dp_mst: Add topology ref history tracking for debugging
For very subtle mistakes with topology refs, it can be rather difficult
to trace them down with the debugging info that we already have. I had
one such issue recently while trying to implement suspend/resume
reprobing for MST, and ended up coming up with this.

Inspired by Chris Wilson's wakeref tracking for i915, this adds a very
similar feature to the DP MST helpers, which allows for partial tracking
of topology refs for both ports and branch devices. This is a lot less
advanced then wakeref tracking: we merely keep a count of all of the
spots where a topology ref has been grabbed or dropped, then dump out
that history in chronological order when a port or branch device's
topology refcount reaches 0. So far, I've found this incredibly useful
for debugging topology refcount errors.

Since this has the potential to be somewhat slow and loud, we add an
expert kernel config option to enable or disable this feature,
CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS.

Changes since v1:
* Don't forget to destroy topology_ref_history_lock
Changes since v4:
* Correct order of kref_put()/topology_ref_history_unlock - we can't
  unlock the history after kref_put() since the memory might have been
  freed by that point
* Don't print message on allocation error failures, the kernel already
  does this for us
Changes since v5:
* Get rid of some leftover usages of %px
* Remove a leftover empty return; statement

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/20191022023641.8026-15-lyude@redhat.com
2019-10-24 14:36:13 -04:00
Lyude Paul
6f85f73821 drm/dp_mst: Add basic topology reprobing when resuming
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
2019-10-24 14:29:48 -04:00
Lyude Paul
79413ed4a1 drm/dp_mst: Lessen indenting in drm_dp_mst_topology_mgr_resume()
Does what it says on the tin.

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/20191022023641.8026-9-lyude@redhat.com
2019-10-24 14:26:32 -04:00
Lyude Paul
dad7d84f88 drm/dp_mst: Don't forget to update port->input in drm_dp_mst_handle_conn_stat()
This probably hasn't caused any problems up until now since it's
probably nearly impossible to encounter this in the wild, however if we
were to receive a connection status notification from the MST hub after
resume while we're in the middle of reprobing the link addresses for a
topology then there's a much larger chance that a port could have
changed from being an output port to input port (or vice versa). If we
forget to update this bit of information, we'll potentially ignore a
valid PDT change on a downstream port because we think it's an input
port.

So, make sure we read the input_port field in connection status
notifications in drm_dp_mst_handle_conn_stat() to prevent this from
happening once we've implemented suspend/resume reprobing.

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/20191022023641.8026-8-lyude@redhat.com
2019-10-24 14:26:12 -04:00
Lyude Paul
3f9b3f02dd drm/dp_mst: Protect drm_dp_mst_port members with locking
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
2019-10-24 14:25:47 -04:00
Lyude Paul
14692a3637 drm/dp_mst: Add probe_lock
Currently, MST lacks locking in a lot of places that really should have
some sort of locking. Hotplugging and link address code paths are some
of the offenders here, as there is actually nothing preventing us from
running a link address probe while at the same time handling a
connection status update request - something that's likely always been
possible but never seen in the wild because hotplugging has been broken
for ages now (with the exception of amdgpu, for reasons I don't think
are worth digging into very far).

Note: I'm going to start using the term "in-memory topology layout" here
to refer to drm_dp_mst_port->mstb and drm_dp_mst_branch->ports.

Locking in these places is a little tougher then it looks though.
Generally we protect anything having to do with the in-memory topology
layout under &mgr->lock. But this becomes nearly impossible to do from
the context of link address probes due to the fact that &mgr->lock is
usually grabbed under random various modesetting locks, meaning that
there's no way we can just invert the &mgr->lock order and keep it
locked throughout the whole process of updating the topology.

Luckily there are only two workers which can modify the in-memory
topology layout: drm_dp_mst_up_req_work() and
drm_dp_mst_link_probe_work(), meaning as long as we prevent these two
workers from traveling the topology layout in parallel with the intent
of updating it we don't need to worry about grabbing &mgr->lock in these
workers for reads. We only need to grab &mgr->lock in these workers for
writes, so that readers outside these two workers are still protected
from the topology layout changing beneath them.

So, add the new &mgr->probe_lock and use it in both
drm_dp_mst_link_probe_work() and drm_dp_mst_up_req_work(). Additionally,
add some more detailed explanations for how this locking is intended to
work to drm_dp_mst_port->mstb and drm_dp_mst_branch->ports.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Sean Paul <sean@poorly.run>
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>
Link: https://patchwork.freedesktop.org/patch/msgid/20191022023641.8026-6-lyude@redhat.com
2019-10-24 14:24:40 -04:00
Lyude Paul
9408cc94eb drm/dp_mst: Handle UP requests asynchronously
Once upon a time, hotplugging devices on MST branches actually worked in
DRM. Now, it only works in amdgpu (likely because of how it's hotplug
handlers are implemented). On both i915 and nouveau, hotplug
notifications from MST branches are noticed - but trying to respond to
them causes messaging timeouts and causes the whole topology state to go
out of sync with reality, usually resulting in the user needing to
replug the entire topology in hopes that it actually fixes things.

The reason for this is because the way we currently handle UP requests
in MST is completely bogus. drm_dp_mst_handle_up_req() is called from
drm_dp_mst_hpd_irq(), which is usually called from the driver's hotplug
handler. Because we handle sending the hotplug event from this function,
we actually cause the driver's hotplug handler (and in turn, all
sideband transactions) to block on
drm_device->mode_config.connection_mutex. This makes it impossible to
send any sideband messages from the driver's connector probing
functions, resulting in the aforementioned sideband message timeout.

There's even more problems with this beyond breaking hotplugging on MST
branch devices. It also makes it almost impossible to protect
drm_dp_mst_port struct members under a lock because we then have to
worry about dealing with all of the lock dependency issues that ensue.

So, let's finally actually fix this issue by handling the processing of
up requests asyncronously. This way we can send sideband messages from
most contexts without having to deal with getting blocked if we hold
connection_mutex. This also fixes MST branch device hotplugging on i915,
finally!

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/20191022023641.8026-5-lyude@redhat.com
2019-10-24 14:24:21 -04:00
Lyude Paul
c485e2c97d drm/dp_mst: Refactor pdt setup/teardown, add more locking
Since we're going to be implementing suspend/resume reprobing very soon,
we need to make sure we are extra careful to ensure that our locking
actually protects the topology state where we expect it to. Turns out
this isn't the case with drm_dp_port_setup_pdt() and
drm_dp_port_teardown_pdt(), both of which change port->mstb without
grabbing &mgr->lock.

Additionally, since most callers of these functions are just using it to
teardown the port's previous PDT and setup a new one we can simplify
things a bit and combine drm_dp_port_setup_pdt() and
drm_dp_port_teardown_pdt() into a single function:
drm_dp_port_set_pdt(). This function also handles actually ensuring that
we grab the correct locks when we need to modify port->mstb.

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/20191022023641.8026-4-lyude@redhat.com
2019-10-24 14:23:55 -04:00
Lyude Paul
d29333cf5c drm/dp_mst: Remove PDT teardown in drm_dp_destroy_port() and refactor
This will allow us to add some locking for port->* members, in
particular the PDT and ->connector, which can't be done from
drm_dp_destroy_port() since we don't know what locks the caller might be
holding.

Note that we already do this in delayed_destroy_work (renamed from
destroy_connector_work in this patch) for ports, we're just making it so
mstbs are also destroyed in this worker.

Changes since v2:
* Clarify commit message
Changes since v4:
* Clarify commit message more

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/20191022023641.8026-3-lyude@redhat.com
2019-10-24 14:23:29 -04:00
Lyude Paul
7cb12d4831 drm/dp_mst: Destroy MSTBs asynchronously
When reprobing an MST topology during resume, we have to account for the
fact that while we were suspended it's possible that mstbs may have been
removed from any ports in the topology. Since iterating downwards in the
topology requires that we hold &mgr->lock, destroying MSTBs from this
context would result in attempting to lock &mgr->lock a second time and
deadlocking.

So, fix this by first moving destruction of MSTBs into
destroy_connector_work, then rename destroy_connector_work and friends
to reflect that they now destroy both ports and mstbs.

Note that even though this means that MSTBs will still be accessible for
a short period of time between their removal from the topology and
delayed destruction, we are still protected against referencing a MSTB
with a refcount of 0 since we use kref_get_unless_zero() in most places.

Changes since v1:
* s/destroy_connector_list/destroy_port_list/
  s/connector_destroy_lock/delayed_destroy_lock/
  s/connector_destroy_work/delayed_destroy_work/
  s/drm_dp_finish_destroy_branch_device/drm_dp_delayed_destroy_mstb/
  s/drm_dp_finish_destroy_port/drm_dp_delayed_destroy_port/
  - danvet
* Use two loops in drm_dp_delayed_destroy_work() - danvet
* Better explain why we need to do this - danvet
* Use cancel_work_sync() instead of flush_work() - flush_work() doesn't
  account for work requeing

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@ffwll.ch>
Reviewed-by: Sean Paul <sean@poorly.run>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191022023641.8026-2-lyude@redhat.com
2019-10-24 14:21:55 -04:00
Wambui Karuga
ddd9b54dee drm: remove unnecessary return variable
Remove unnecessary variable `ret` in drm_dp_atomic_find_vcpi_slots()
only used to hold the function return value and have the function
return the value directly.
Issue found by coccinelle:
@@
local idexpression ret;
expression e;
@@

-ret =
+return
     e;
-return ret;

Signed-off-by: Wambui Karuga <wambui.karugax@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20191019071840.16877-1-wambui@karuga.xyz
2019-10-22 11:17:43 +02:00
Lucas De Marchi
67c698fc5e drm/dp-mst: fix warning on unused var
Fixes: 83fa9842af ("drm/dp-mst: Drop connection_mutex check")
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20191011010907.103309-8-lucas.demarchi@intel.com
2019-10-14 19:48:07 +02:00
Daniel Vetter
83fa9842af drm/dp-mst: Drop connection_mutex check
Private atomic objects have grown their own locking with

commit b962a12050
Author: Rob Clark <robdclark@gmail.com>
Date:   Mon Oct 22 14:31:22 2018 +0200

    drm/atomic: integrate modeset lock with private objects

which means we're no longer relying on connection_mutex for mst state
locking needs.

Cc: Lyude Paul <lyude@redhat.com>
Cc: Sean Paul <sean@poorly.run>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191009224113.5432-1-daniel.vetter@ffwll.ch
2019-10-10 15:40:35 +02:00
Jani Nikula
f0a8f533ad drm/print: add drm_debug_enabled()
Add helper to check if a drm debug category is enabled. Convert drm core
to use it. No functional changes.

v2: Move unlikely() to drm_debug_enabled() (Eric)

v3: Keep unlikely() when combined with other conditions (Eric)

Cc: Eric Engestrom <eric@engestrom.ch>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Eric Engestrom <eric@engestrom.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191001140614.26909-1-jani.nikula@intel.com
2019-10-02 16:28:55 +03:00
Ville Syrjälä
ed20b7d5c6 drm/dp/mst: Replace the fixed point thing with straight calculation
Get rid of the drm_fixp_from_fraction() usage and just do the
straightforward calculation directly.

Cc: Lyude Paul <lyude@redhat.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190925141442.23236-3-ville.syrjala@linux.intel.com
Reviewed-by: Lyude Paul <lyude@redhat.com>
2019-09-30 20:57:42 +03:00
Ville Syrjälä
0c3bb15cfc drm/dp/mst: Handle arbitrary DP_LINK_BW values
Make drm_dp_get_vc_payload() tolerate arbitrary DP_LINK_BW_*
values, just like drm_dp_bw_code_to_link_rate() does since commit
57a1b08937 ("drm: Make the bw/link rate calculations more forgiving").

Cc: Lyude Paul <lyude@redhat.com>
Cc: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190925141442.23236-2-ville.syrjala@linux.intel.com
Reviewed-by: Lyude Paul <lyude@redhat.com>
2019-09-30 20:56:11 +03:00
Ville Syrjälä
db0cc143b6 drm/dp/mst: Reduce nested ifs
Replace the nested ifs with a single if and a logical AND.

Cc: Lyude Paul <lyude@redhat.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190925141442.23236-1-ville.syrjala@linux.intel.com
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
2019-09-30 20:54:20 +03:00
Matt Roper
caf81ec6cd drm: Destroy the correct mutex name in drm_dp_mst_topology_mgr_destroy
It looks like one of the topology manager mutexes may have been renamed
during a rebase, but the destruction function wasn't updated with the
new name:

   error: ‘struct drm_dp_mst_topology_mgr’ has no member named
   ‘delayed_destroy_lock’

Fixes: 50094b5dcd ("drm/dp_mst: Destroy topology_mgr mutexes")
Cc: Lyude Paul <lyude@redhat.com>
Cc: Sean Paul <sean@poorly.run>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190925224617.24027-1-matthew.d.roper@intel.com
2019-09-25 19:28:59 -04:00
Lyude Paul
e2839ff692 drm/dp_mst: Rename drm_dp_add_port and drm_dp_update_port
The names for these functions are rather confusing. drm_dp_add_port()
sounds like a function that would simply create a port and add it to a
topology, and do nothing more. Similarly, drm_dp_update_port() would be
assumed to be the function that should be used to update port
information after initial creation.

While those assumptions are currently correct in how these functions are
used, a quick glance at drm_dp_add_port() reveals that drm_dp_add_port()
can also update the information on a port, and seems explicitly designed
to do so. This can be explained pretty simply by the fact that there's
more situations that would involve updating the port information based
on a link address response as opposed to a connection status
notification than the driver's initial topology probe. Case in point:
reprobing link addresses after suspend/resume.

Since we're about to start using drm_dp_add_port() differently for
suspend/resume reprobing, let's rename both functions to clarify what
they actually do.

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>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-18-lyude@redhat.com
2019-09-25 16:35:15 -04:00
Lyude Paul
50094b5dcd drm/dp_mst: Destroy topology_mgr mutexes
Turns out we've been forgetting for a while now to actually destroy any
of the mutexes that we create in drm_dp_mst_topology_mgr. So, let's 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>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-15-lyude@redhat.com
2019-09-25 16:27:53 -04:00
Lyude Paul
37dfdc55ff drm/dp_mst: Cleanup drm_dp_send_link_address() a bit
Declare local pointer to the drm_dp_link_address_ack_reply struct
instead of constantly dereferencing it through the union in
txmsg->reply. Then, invert the order of conditionals so we don't have to
do the bulk of the work inside them, and can wrap lines even less. Then
finally, rearrange variable declarations a bit.

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>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-16-lyude@redhat.com
2019-09-03 19:37:00 -04:00
Lyude Paul
8b1e589d13 drm/dp_mst: Refactor drm_dp_mst_handle_down_rep()
* Remove the big ugly have_eomt conditional
* Store &mgr->down_rep_recv.initial_hdr in a var to make line wrapping
  easier
* Remove duplicate memset() calls
* Actually wrap lines

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>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-14-lyude@redhat.com
2019-09-03 19:37:00 -04:00
Lyude Paul
a29d881875 drm/dp_mst: Refactor drm_dp_mst_handle_up_req()
There's a couple of changes here, so to summarize:

* Remove the big ugly mgr->up_req_recv.have_eomt conditional to save on
  indenting
* Store &mgr->up_req_recv.initial_hdr in a variable so we don't keep
  going over 80 character long lines
* De-duplicate code for calling drm_dp_send_up_ack_reply() and getting
  the MSTB via it's GUID
* Remove all of the duplicate calls to memset() and just use a goto
  instead
* Actually do line wrapping
* Remove the unnecessary if (mstb) check before calling
  drm_dp_mst_topology_put_mstb() - we are guaranteed to always have
  mstb != NULL at that point in the function

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>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-13-lyude@redhat.com
2019-09-03 19:37:00 -04:00
Lyude Paul
fde61a7a7d drm/dp_mst: Constify guid in drm_dp_get_mst_branch_by_guid()
And it's helper, we'll be using this in just a moment.

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>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-12-lyude@redhat.com
2019-09-03 19:36:59 -04:00
Lyude Paul
60f9ae9d0d drm/dp_mst: Remove huge conditional in drm_dp_mst_handle_up_req()
Which reduces indentation and makes this function more legible.

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>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-11-lyude@redhat.com
2019-09-03 19:36:51 -04:00
Lyude Paul
95b0013d20 drm/dp_mst: Refactor drm_dp_send_enum_path_resources
Use more pointers so we don't have to write out
txmsg->reply.u.path_resources each time. Also, fix line wrapping +
rearrange local variables.

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>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-10-lyude@redhat.com
2019-09-03 19:30:47 -04:00
Lyude Paul
2f015ec6ea drm/dp_mst: Add sideband down request tracing + selftests
Unfortunately the DP MST helpers do not have much in the way of
debugging utilities. So, let's add some!

This adds basic debugging output for down sideband requests that we send
from the driver, so that we can actually discern what's happening when
sideband requests timeout.

Since there wasn't really a good way of testing that any of this worked,
I ended up writing simple selftests that lightly test sideband message
encoding and decoding as well. Enjoy!

Changes since v1:
* Clean up DO_TEST() and sideband_msg_req_encode_decode() - danvet
* Get rid of pr_fmt(), just define a prefix string instead and use
  drm_printf()
* Check highest bit of VCPI in drm_dp_decode_sideband_req() - danvet
* Make the switch case order between drm_dp_decode_sideband_req() and
  drm_dp_encode_sideband_req() the same - danvet
* Only check DRM_UT_DP - danvet
* Clean up sideband_msg_req_equal() from selftests a bit, and add
  comments explaining why we can't just use memcmp - danvet

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>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-8-lyude@redhat.com
2019-09-03 19:30:06 -04:00
Lyude Paul
aa2a2fe138 drm/dp_mst: Combine redundant cases in drm_dp_encode_sideband_req()
Noticed this while working on adding a drm_dp_decode_sideband_req().
DP_POWER_DOWN_PHY/DP_POWER_UP_PHY both use the same struct as
DP_ENUM_PATH_RESOURCES, so we can just combine their cases.

Changes since v2:
* Fix commit message

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
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>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903215702.16984-1-lyude@redhat.com
2019-09-03 19:29:35 -04:00
Lyude Paul
7cbce45d62 drm/dp_mst: Move test_calc_pbn_mode() into an actual selftest
Yes, apparently we've been testing this for every single driver load for
quite a long time now. At least that means our PBN calculation is solid!

Anyway, introduce self tests for MST and move this into there.

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>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-5-lyude@redhat.com
2019-09-03 19:28:20 -04:00
Lyude Paul
3ba64aa36c drm/dp_mst: Get rid of list clear in destroy_connector_work
This seems to be some leftover detritus from before the port/mstb kref
cleanup and doesn't do anything anymore, so get rid of it.

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>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-3-lyude@redhat.com
2019-09-03 19:27:37 -04:00