linux.git/include/drm/display, branch v6.6.132 Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git drm/dp_mst: Fix drm RAD print 2025-04-10T12:37:27+00:00 Wayne Lin Wayne.Lin@amd.com 2025-01-13T09:10:59+00:00 c3b8e7c6809a5e27437d43c185b0a4e50f68586e [ Upstream commit 6bbce873a9c97cb12f5455c497be279ac58e707f ] [Why] The RAD of sideband message printed today is incorrect. For RAD stored within MST branch - If MST branch LCT is 1, it's RAD array is untouched and remained as 0. - If MST branch LCT is larger than 1, use nibble to store the up facing port number in cascaded sequence as illustrated below: u8 RAD[0] = (LCT_2_UFP << 4) | LCT_3_UFP RAD[1] = (LCT_4_UFP << 4) | LCT_5_UFP ... In drm_dp_mst_rad_to_str(), it wrongly to use BIT_MASK(4) to fetch the port number of one nibble. [How] Adjust the code by: - RAD array items are valuable only for LCT >= 1. - Use 0xF as the mask to replace BIT_MASK(4) V2: - Document how RAD is constructed (Imre) V3: - Adjust the comment for rad[] so kdoc formats it properly (Lyude) Fixes: 2f015ec6eab6 ("drm/dp_mst: Add sideband down request tracing + selftests") Cc: Imre Deak <imre.deak@intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Harry Wentland <hwentlan@amd.com> Cc: Lyude Paul <lyude@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com> Signed-off-by: Wayne Lin <Wayne.Lin@amd.com> Signed-off-by: Lyude Paul <lyude@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20250113091100.3314533-2-Wayne.Lin@amd.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 6bbce873a9c97cb12f5455c497be279ac58e707f ]

[Why]
The RAD of sideband message printed today is incorrect.
For RAD stored within MST branch
- If MST branch LCT is 1, it's RAD array is untouched and remained as 0.
- If MST branch LCT is larger than 1, use nibble to store the up facing
  port number in cascaded sequence as illustrated below:

  u8 RAD[0] = (LCT_2_UFP << 4) | LCT_3_UFP
     RAD[1] = (LCT_4_UFP << 4) | LCT_5_UFP
     ...

In drm_dp_mst_rad_to_str(), it wrongly to use BIT_MASK(4) to fetch the port
number of one nibble.

[How]
Adjust the code by:
- RAD array items are valuable only for LCT >= 1.
- Use 0xF as the mask to replace BIT_MASK(4)

V2:
- Document how RAD is constructed (Imre)

V3:
- Adjust the comment for rad[] so kdoc formats it properly (Lyude)

Fixes: 2f015ec6eab6 ("drm/dp_mst: Add sideband down request tracing + selftests")
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Cc: Lyude Paul <lyude@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250113091100.3314533-2-Wayne.Lin@amd.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
drm/dp_mst: Add a helper to queue a topology probe 2025-04-07T08:06:36+00:00 Imre Deak imre.deak@intel.com 2024-07-22T16:54:51+00:00 5f57a96e92c60f62da91d58ceb5e5acd40e7d594 commit dbaeef363ea54f4c18112874b77503c72ba60fec upstream. A follow up i915 patch will need to reprobe the MST topology after the initial probing, add a helper for this. Cc: Lyude Paul <lyude@redhat.com> Cc: dri-devel@lists.freedesktop.org Reviewed-by: Lyude Paul <lyude@redhat.com> Signed-off-by: Imre Deak <imre.deak@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20240722165503.2084999-3-imre.deak@intel.com Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit dbaeef363ea54f4c18112874b77503c72ba60fec upstream.

A follow up i915 patch will need to reprobe the MST topology after the
initial probing, add a helper for this.

Cc: Lyude Paul <lyude@redhat.com>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240722165503.2084999-3-imre.deak@intel.com
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/dp_mst: Fix resetting msg rx state after topology removal 2024-12-14T18:59:55+00:00 Imre Deak imre.deak@intel.com 2024-12-03T16:02:17+00:00 d834d20d2e86c52ed5cab41763fa61e6071680ef commit a6fa67d26de385c3c7a23c1e109a0e23bfda4ec7 upstream. If the MST topology is removed during the reception of an MST down reply or MST up request sideband message, the drm_dp_mst_topology_mgr::up_req_recv/down_rep_recv states could be reset from one thread via drm_dp_mst_topology_mgr_set_mst(false), racing with the reading/parsing of the message from another thread via drm_dp_mst_handle_down_rep() or drm_dp_mst_handle_up_req(). The race is possible since the reader/parser doesn't hold any lock while accessing the reception state. This in turn can lead to a memory corruption in the reader/parser as described by commit bd2fccac61b4 ("drm/dp_mst: Fix MST sideband message body length check"). Fix the above by resetting the message reception state if needed before reading/parsing a message. Another solution would be to hold the drm_dp_mst_topology_mgr::lock for the whole duration of the message reception/parsing in drm_dp_mst_handle_down_rep() and drm_dp_mst_handle_up_req(), however this would require a bigger change. Since the fix is also needed for stable, opting for the simpler solution in this patch. Cc: Lyude Paul <lyude@redhat.com> Cc: <stable@vger.kernel.org> Fixes: 1d082618bbf3 ("drm/display/dp_mst: Fix down/up message handling after sink disconnect") Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/13056 Reviewed-by: Lyude Paul <lyude@redhat.com> Signed-off-by: Imre Deak <imre.deak@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20241203160223.2926014-2-imre.deak@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a6fa67d26de385c3c7a23c1e109a0e23bfda4ec7 upstream.

If the MST topology is removed during the reception of an MST down reply
or MST up request sideband message, the
drm_dp_mst_topology_mgr::up_req_recv/down_rep_recv states could be reset
from one thread via drm_dp_mst_topology_mgr_set_mst(false), racing with
the reading/parsing of the message from another thread via
drm_dp_mst_handle_down_rep() or drm_dp_mst_handle_up_req(). The race is
possible since the reader/parser doesn't hold any lock while accessing
the reception state. This in turn can lead to a memory corruption in the
reader/parser as described by commit bd2fccac61b4 ("drm/dp_mst: Fix MST
sideband message body length check").

Fix the above by resetting the message reception state if needed before
reading/parsing a message. Another solution would be to hold the
drm_dp_mst_topology_mgr::lock for the whole duration of the message
reception/parsing in drm_dp_mst_handle_down_rep() and
drm_dp_mst_handle_up_req(), however this would require a bigger change.
Since the fix is also needed for stable, opting for the simpler solution
in this patch.

Cc: Lyude Paul <lyude@redhat.com>
Cc: <stable@vger.kernel.org>
Fixes: 1d082618bbf3 ("drm/display/dp_mst: Fix down/up message handling after sink disconnect")
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/13056
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241203160223.2926014-2-imre.deak@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/dp: Don't attempt AUX transfers when eDP panels are not powered 2024-06-12T09:11:57+00:00 Douglas Anderson dianders@chromium.org 2024-02-02T22:11:16+00:00 9429b12dfcbd7eca89795730305cd1400bf97ec9 [ Upstream commit 8df1ddb5bf11ab820ad991e164dab82c0960add9 ] If an eDP panel is not powered on then any attempts to talk to it over the DP AUX channel will timeout. Unfortunately these attempts may be quite slow. Userspace can initiate these attempts either via a /dev/drm_dp_auxN device or via the created i2c device. Making the DP AUX drivers timeout faster is a difficult proposition. In theory we could just poll the panel's HPD line in the AUX transfer function and immediately return an error there. However, this is easier said than done. For one thing, there's no hard requirement to hook the HPD line up for eDP panels and it's OK to just delay a fixed amount. For another thing, the HPD line may not be fast to probe. On parade-ps8640 we need to wait for the bridge chip's firmware to boot before we can get the HPD line and this is a slow process. The fact that the transfers are taking so long to timeout is causing real problems. The open source fwupd daemon sometimes scans DP busses looking for devices whose firmware need updating. If it happens to scan while a panel is turned off this scan can take a long time. The fwupd daemon could try to be smarter and only scan when eDP panels are turned on, but we can also improve the behavior in the kernel. Let's let eDP panels drivers specify that a panel is turned off and then modify the common AUX transfer code not to attempt a transfer in this case. Tested-by: Steev Klimaszewski <steev@kali.org> Reviewed-by: Hsin-Yi Wang <hsinyi@chromium.org> Tested-by: Eizan Miyamoto <eizan@chromium.org> Acked-by: Neil Armstrong <neil.armstrong@linaro.org> Signed-off-by: Douglas Anderson <dianders@chromium.org> Link: https://patchwork.freedesktop.org/patch/msgid/20240202141109.1.I24277520ac754ea538c9b14578edc94e1df11b48@changeid Stable-dep-of: 5e842d55bad7 ("drm/panel: atna33xc20: Fix unbalanced regulator in the case HPD doesn't assert") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 8df1ddb5bf11ab820ad991e164dab82c0960add9 ]

If an eDP panel is not powered on then any attempts to talk to it over
the DP AUX channel will timeout. Unfortunately these attempts may be
quite slow. Userspace can initiate these attempts either via a
/dev/drm_dp_auxN device or via the created i2c device.

Making the DP AUX drivers timeout faster is a difficult proposition.
In theory we could just poll the panel's HPD line in the AUX transfer
function and immediately return an error there. However, this is
easier said than done. For one thing, there's no hard requirement to
hook the HPD line up for eDP panels and it's OK to just delay a fixed
amount. For another thing, the HPD line may not be fast to probe. On
parade-ps8640 we need to wait for the bridge chip's firmware to boot
before we can get the HPD line and this is a slow process.

The fact that the transfers are taking so long to timeout is causing
real problems. The open source fwupd daemon sometimes scans DP busses
looking for devices whose firmware need updating. If it happens to
scan while a panel is turned off this scan can take a long time. The
fwupd daemon could try to be smarter and only scan when eDP panels are
turned on, but we can also improve the behavior in the kernel.

Let's let eDP panels drivers specify that a panel is turned off and
then modify the common AUX transfer code not to attempt a transfer in
this case.

Tested-by: Steev Klimaszewski <steev@kali.org>
Reviewed-by: Hsin-Yi Wang <hsinyi@chromium.org>
Tested-by: Eizan Miyamoto <eizan@chromium.org>
Acked-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240202141109.1.I24277520ac754ea538c9b14578edc94e1df11b48@changeid
Stable-dep-of: 5e842d55bad7 ("drm/panel: atna33xc20: Fix unbalanced regulator in the case HPD doesn't assert")
Signed-off-by: Sasha Levin <sashal@kernel.org>
drm/dp_mst: Fix fractional DSC bpp handling 2024-01-25T23:35:31+00:00 Ville Syrjälä ville.syrjala@linux.intel.com 2023-10-24T01:08:57+00:00 4e042f022255604c68ab5d5f73c8f437d24d651e [ Upstream commit 7707dd6022593f3edd8e182e7935870cf326f874 ] The current code does '(bpp << 4) / 16' in the MST PBN calculation, but that is just the same as 'bpp' so the DSC codepath achieves absolutely nothing. Fix it up so that the fractional part of the bpp value is actually used instead of truncated away. 64*1006 has enough zero lsbs that we can just shift that down in the dividend and thus still manage to stick to a 32bit divisor. And while touching this, let's just make the whole thing more straightforward by making the passed in bpp value .4 binary fixed point always, instead of having to pass in different things based on whether DSC is enabled or not. v2: - Fix DSC kunit test cases. Cc: Manasi Navare <manasi.d.navare@intel.com> Cc: Lyude Paul <lyude@redhat.com> Cc: Harry Wentland <harry.wentland@amd.com> Cc: David Francis <David.Francis@amd.com> Cc: Mikita Lipski <mikita.lipski@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Fixes: dc48529fb14e ("drm/dp_mst: Add PBN calculation for DSC modes") Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> [Imre: Fix kunit test cases] Acked-by: Maxime Ripard <mripard@kernel.org> Reviewed-by: Lyude Paul <lyude@redhat.com> Acked-by: Harry Wentland <harry.wentland@amd.com> Signed-off-by: Imre Deak <imre.deak@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20231030155843.2251023-3-imre.deak@intel.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 7707dd6022593f3edd8e182e7935870cf326f874 ]

The current code does '(bpp << 4) / 16' in the MST PBN
calculation, but that is just the same as 'bpp' so the
DSC codepath achieves absolutely nothing. Fix it up so that
the fractional part of the bpp value is actually used instead
of truncated away. 64*1006 has enough zero lsbs that we can
just shift that down in the dividend and thus still manage
to stick to a 32bit divisor.

And while touching this, let's just make the whole thing more
straightforward by making the passed in bpp value .4 binary
fixed point always, instead of having to pass in different
things based on whether DSC is enabled or not.

v2:
- Fix DSC kunit test cases.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: David Francis <David.Francis@amd.com>
Cc: Mikita Lipski <mikita.lipski@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Fixes: dc48529fb14e ("drm/dp_mst: Add PBN calculation for DSC modes")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
[Imre: Fix kunit test cases]
Acked-by: Maxime Ripard <mripard@kernel.org>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231030155843.2251023-3-imre.deak@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
drm/display/dp: Fix the DP DSC Receiver cap size 2023-08-22T07:52:11+00:00 Ankit Nautiyal ankit.k.nautiyal@intel.com 2023-08-18T04:44:36+00:00 5ad1ab30ac0809d2963ddcf39ac34317a24a2f17 DP DSC Receiver Capabilities are exposed via DPCD 60h-6Fh. Fix the DSC RECEIVER CAP SIZE accordingly. Fixes: ffddc4363c28 ("drm/dp: Add DP DSC DPCD receiver capability size define and missing SHIFT") Cc: Anusha Srivatsa <anusha.srivatsa@intel.com> Cc: Manasi Navare <manasi.d.navare@intel.com> Cc: <stable@vger.kernel.org> # v5.0+ Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com> Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20230818044436.177806-1-ankit.k.nautiyal@intel.com 
DP DSC Receiver Capabilities are exposed via DPCD 60h-6Fh.
Fix the DSC RECEIVER CAP SIZE accordingly.

Fixes: ffddc4363c28 ("drm/dp: Add DP DSC DPCD receiver capability size define and missing SHIFT")
Cc: Anusha Srivatsa <anusha.srivatsa@intel.com>
Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: <stable@vger.kernel.org> # v5.0+

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230818044436.177806-1-ankit.k.nautiyal@intel.com
Merge tag 'drm-msm-next-2023-06-18' of https://gitlab.freedesktop.org/drm/msm into drm-next 2023-06-19T06:01:46+00:00 Dave Airlie airlied@redhat.com 2023-06-19T06:01:45+00:00 2222dcb0775d36de28992f56455ab3967b30d380 Updates for v6.5.. this includes a backmerg of drm-next tree to be able to use new DRM DSC helpers. Core: + Add Marijn Suijten as drm/msm reviewer + Adreno A660 bindings + SM8350 MDSS bindings fix + Fix adreno_is_a690() warnings + More generic (DRM) and MSM-specific DSC helpers DP: + Removed obsolete USB-PD remains + Documented DP compatible string for sm8550 platform DPU: + Enable missing features (DSPP, DSC, split display) on sc8180x, sc8280xp, sm8450 + Enabled writeback on sc7280 + Implemented tearcheck support to support vsync on SM150 and newer platforms + Native HDMI output support + Dropped unused features: regdma, GC, IGC + Fixed the DSC flush operations + Simplified QoS handling, removing obsolete and unused features and merging SSPP and WB code paths + Reworked dpu_encoder initialisation path + Enabled DSPP support on sdm845 + Disabled color-management if DSPP blocks are not available + Added support for DSC 1.2 blocks found on sm8350 and later + Added .fb_dirty to fix CMD panels DSI: + Drop powerup quirks in favour of using pre_enable_prev_first for downstream bridges + Fixed 14nm DSI PHY programming + Added support for DSI and 28nm DSI PHY on MSM8226 platform + Make use of DRM and MSM DSC helpers MDP5: + Added support for display controller on MSM8226 platform GPU: + A690 support + Don't set IO_PGTABLE_QUIRK_ARM_OUTER_WBWA on devices with coherent SMMU (like A690) + Move cmdstream dumping out of fence signaling path + Cleanups + Support for a6xx devices without GMU (aka "GMU wrapper" + a610 support + a619_holi support (a619 variant without GMU) Signed-off-by: Dave Airlie <airlied@redhat.com> From: Rob Clark <robdclark@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/CAF6AEGsUB=tRB4nR6ZCJMuLhro5zN3BQWUSywVYbaipqqDZ_cQ@mail.gmail.com 
Updates for v6.5.. this includes a backmerg of drm-next tree to be able
to use new DRM DSC helpers.

Core:
+ Add Marijn Suijten as drm/msm reviewer
+ Adreno A660 bindings
+ SM8350 MDSS bindings fix
+ Fix adreno_is_a690() warnings
+ More generic (DRM) and MSM-specific DSC helpers

DP:
+ Removed obsolete USB-PD remains
+ Documented DP compatible string for sm8550 platform

DPU:
+ Enable missing features (DSPP, DSC, split display) on sc8180x,
  sc8280xp, sm8450
+ Enabled writeback on sc7280
+ Implemented tearcheck support to support vsync on SM150 and
  newer platforms
+ Native HDMI output support
+ Dropped unused features: regdma, GC, IGC
+ Fixed the DSC flush operations
+ Simplified QoS handling, removing obsolete and unused features
  and merging SSPP and WB code paths
+ Reworked dpu_encoder initialisation path
+ Enabled DSPP support on sdm845
+ Disabled color-management if DSPP blocks are not available
+ Added support for DSC 1.2 blocks found on sm8350 and later
+ Added .fb_dirty to fix CMD panels

DSI:
+ Drop powerup quirks in favour of using pre_enable_prev_first for
  downstream bridges
+ Fixed 14nm DSI PHY programming
+ Added support for DSI and 28nm DSI PHY on MSM8226 platform
+ Make use of DRM and MSM DSC helpers

MDP5:
+ Added support for display controller on MSM8226 platform

GPU:
+ A690 support
+ Don't set IO_PGTABLE_QUIRK_ARM_OUTER_WBWA on devices with coherent SMMU
  (like A690)
+ Move cmdstream dumping out of fence signaling path
+ Cleanups
+ Support for a6xx devices without GMU (aka "GMU wrapper"
+ a610 support
+ a619_holi support (a619 variant without GMU)

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Rob Clark <robdclark@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/CAF6AEGsUB=tRB4nR6ZCJMuLhro5zN3BQWUSywVYbaipqqDZ_cQ@mail.gmail.com
drm/dp_mst: Clear MSG_RDY flag before sending new message 2023-06-15T21:55:41+00:00 Wayne Lin Wayne.Lin@amd.com 2023-04-17T09:08:12+00:00 72f1de49ffb90b29748284f27f1d6b829ab1de95 [Why] The sequence for collecting down_reply from source perspective should be: Request_n->repeat (get partial reply of Request_n->clear message ready flag to ack DPRX that the message is received) till all partial replies for Request_n are received->new Request_n+1. Now there is chance that drm_dp_mst_hpd_irq() will fire new down request in the tx queue when the down reply is incomplete. Source is restricted to generate interveleaved message transactions so we should avoid it. Also, while assembling partial reply packets, reading out DPCD DOWN_REP Sideband MSG buffer + clearing DOWN_REP_MSG_RDY flag should be wrapped up as a complete operation for reading out a reply packet. Kicking off a new request before clearing DOWN_REP_MSG_RDY flag might be risky. e.g. If the reply of the new request has overwritten the DPRX DOWN_REP Sideband MSG buffer before source writing one to clear DOWN_REP_MSG_RDY flag, source then unintentionally flushes the reply for the new request. Should handle the up request in the same way. [How] Separete drm_dp_mst_hpd_irq() into 2 steps. After acking the MST IRQ event, driver calls drm_dp_mst_hpd_irq_send_new_request() and might trigger drm_dp_mst_kick_tx() only when there is no on going message transaction. Changes since v1: * Reworked on review comments received -> Adjust the fix to let driver explicitly kick off new down request when mst irq event is handled and acked -> Adjust the commit message Changes since v2: * Adjust the commit message * Adjust the naming of the divided 2 functions and add a new input parameter "ack". * Adjust code flow as per review comments. Changes since v3: * Update the function description of drm_dp_mst_hpd_irq_handle_event Changes since v4: * Change ack of drm_dp_mst_hpd_irq_handle_event() to be an array align the size of esi[] Signed-off-by: Wayne Lin <Wayne.Lin@amd.com> Reviewed-by: Lyude Paul <lyude@redhat.com> Acked-by: Jani Nikula <jani.nikula@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[Why]
The sequence for collecting down_reply from source perspective should
be:

Request_n->repeat (get partial reply of Request_n->clear message ready
flag to ack DPRX that the message is received) till all partial
replies for Request_n are received->new Request_n+1.

Now there is chance that drm_dp_mst_hpd_irq() will fire new down
request in the tx queue when the down reply is incomplete. Source is
restricted to generate interveleaved message transactions so we should
avoid it.

Also, while assembling partial reply packets, reading out DPCD DOWN_REP
Sideband MSG buffer + clearing DOWN_REP_MSG_RDY flag should be
wrapped up as a complete operation for reading out a reply packet.
Kicking off a new request before clearing DOWN_REP_MSG_RDY flag might
be risky. e.g. If the reply of the new request has overwritten the
DPRX DOWN_REP Sideband MSG buffer before source writing one to clear
DOWN_REP_MSG_RDY flag, source then unintentionally flushes the reply
for the new request. Should handle the up request in the same way.

[How]
Separete drm_dp_mst_hpd_irq() into 2 steps. After acking the MST IRQ
event, driver calls drm_dp_mst_hpd_irq_send_new_request() and might
trigger drm_dp_mst_kick_tx() only when there is no on going message
transaction.

Changes since v1:
* Reworked on review comments received
-> Adjust the fix to let driver explicitly kick off new down request
when mst irq event is handled and acked
-> Adjust the commit message

Changes since v2:
* Adjust the commit message
* Adjust the naming of the divided 2 functions and add a new input
  parameter "ack".
* Adjust code flow as per review comments.

Changes since v3:
* Update the function description of drm_dp_mst_hpd_irq_handle_event

Changes since v4:
* Change ack of drm_dp_mst_hpd_irq_handle_event() to be an array align
  the size of esi[]

Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/display/dsc: Add drm_dsc_get_bpp_int helper 2023-06-15T09:58:56+00:00 Jessica Zhang quic_jesszhan@quicinc.com 2023-05-24T17:45:16+00:00 68858328124162b9b42bc7b8232eee1915cc1d8f Add helper to get the integer value of drm_dsc_config.bits_per_pixel Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com> Patchwork: https://patchwork.freedesktop.org/patch/539268/ Link: https://lore.kernel.org/r/20230329-rfc-msm-dsc-helper-v14-3-bafc7be95691@quicinc.com Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> 
Add helper to get the integer value of drm_dsc_config.bits_per_pixel

Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/539268/
Link: https://lore.kernel.org/r/20230329-rfc-msm-dsc-helper-v14-3-bafc7be95691@quicinc.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
drm/display/dsc: add helper to set semi-const parameters 2023-06-15T09:58:56+00:00 Dmitry Baryshkov dmitry.baryshkov@linaro.org 2023-05-24T17:45:15+00:00 e871a70d8ccd6dbcb30f081f5d3d8854380422fe Add a helper setting config values which are typically constant across operating modes (table E-4 of the standard) and mux_word_size (which is a const according to 3.5.2). Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com> Patchwork: https://patchwork.freedesktop.org/patch/539280/ Link: https://lore.kernel.org/r/20230329-rfc-msm-dsc-helper-v14-2-bafc7be95691@quicinc.com Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> 
Add a helper setting config values which are typically constant across
operating modes (table E-4 of the standard) and mux_word_size (which is
a const according to 3.5.2).

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/539280/
Link: https://lore.kernel.org/r/20230329-rfc-msm-dsc-helper-v14-2-bafc7be95691@quicinc.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>