<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/drivers/gpu/drm/msm/dp/dp_ctrl.c, branch v5.15.215</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v5.15.215</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v5.15.215'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2024-09-04T11:23:35+00:00</updated>
<entry>
<title>drm/msm/dp: reset the link phy params before link training</title>
<updated>2024-09-04T11:23:35+00:00</updated>
<author>
<name>Abhinav Kumar</name>
<email>quic_abhinavk@quicinc.com</email>
</author>
<published>2024-07-25T22:04:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=5c28ce95f8a37fb128ec3041b50229d68c14a652'/>
<id>urn:sha1:5c28ce95f8a37fb128ec3041b50229d68c14a652</id>
<content type='text'>
[ Upstream commit 319aca883bfa1b85ee08411541b51b9a934ac858 ]

Before re-starting link training reset the link phy params namely
the pre-emphasis and voltage swing levels otherwise the next
link training begins at the previously cached levels which can result
in link training failures.

Fixes: 8ede2ecc3e5e ("drm/msm/dp: Add DP compliance tests on Snapdragon Chipsets")
Reviewed-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Tested-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt; # SM8350-HDK
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Patchwork: https://patchwork.freedesktop.org/patch/605946/
Link: https://lore.kernel.org/r/20240725220450.131245-1-quic_abhinavk@quicinc.com
Signed-off-by: Abhinav Kumar &lt;quic_abhinavk@quicinc.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: do not reinitialize phy unless retry during link training</title>
<updated>2023-10-19T21:05:33+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2023-08-08T22:19:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=b9de60b6830ce16e9544e8832341e585f0c636aa'/>
<id>urn:sha1:b9de60b6830ce16e9544e8832341e585f0c636aa</id>
<content type='text'>
[ Upstream commit 0c1a2e69bcb506f48ebf94bd199bab0b93f66da2 ]

DP PHY re-initialization done using dp_ctrl_reinitialize_mainlink() will
cause PLL unlocked initially and then PLL gets locked at the end of
initialization. PLL_UNLOCKED interrupt will fire during this time if the
interrupt mask is enabled.

However currently DP driver link training implementation incorrectly
re-initializes PHY unconditionally during link training as the PHY was
already configured in dp_ctrl_enable_mainlink_clocks().

Fix this by re-initializing the PHY only if the previous link training
failed.

[drm:dp_aux_isr] *ERROR* Unexpected DP AUX IRQ 0x01000000 when not busy

Fixes: c943b4948b58 ("drm/msm/dp: add displayPort driver support")
Closes: https://gitlab.freedesktop.org/drm/msm/-/issues/30
Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Tested-by: Abhinav Kumar &lt;quic_abhinavk@quicinc.com&gt; # sc7280
Reviewed-by: Abhinav Kumar &lt;quic_abhinavk@quicinc.com&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Reviewed-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Tested-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Patchwork: https://patchwork.freedesktop.org/patch/551847/
Link: https://lore.kernel.org/r/1691533190-19335-1-git-send-email-quic_khsieh@quicinc.com
[quic_abhinavk@quicinc.com: added line break in commit text]
Signed-off-by: Abhinav Kumar &lt;quic_abhinavk@quicinc.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: delete DP_RECOVERED_CLOCK_OUT_EN to fix tps4</title>
<updated>2022-09-08T10:28:01+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2022-08-11T22:57:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=0a4f633548c495f8598b546a0f3eba5e2f101dbe'/>
<id>urn:sha1:0a4f633548c495f8598b546a0f3eba5e2f101dbe</id>
<content type='text'>
[ Upstream commit 032d57960176ac01cc5adff5bcc5eb51317f8781 ]

Data Symbols scrambled is required for tps4 at link training 2.
Therefore SCRAMBLING_DISABLE bit should not be set for tps4 to
work.

RECOVERED_CLOCK_OUT_EN is for enable simple EYE test for jitter
measurement with minimal equipment for embedded applications purpose
and is not required to be set during normal operation. Current
implementation always have RECOVERED_CLOCK_OUT_EN bit set which
cause SCRAMBLING_DISABLE bit wrongly set at tps4 which prevent
tps4 from working.

This patch delete setting RECOVERED_CLOCK_OUT_EN to fix
SCRAMBLING_DISABLE be wrongly set at tps4.

Changes in v2:
-- fix Fixes tag

Changes in v3:
-- revise commit text

Changes in v4:
-- fix commit text newline

Changes in v5:
-- fix commit text line over 75 chars

Fixes: c943b4948b58 ("drm/msm/dp: add displayPort driver support")
Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;

Reviewed-by: Abhinav Kumar &lt;quic_abhinavk@quicinc.com&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Reviewed-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Patchwork: https://patchwork.freedesktop.org/patch/497194/
Link: https://lore.kernel.org/r/1660258670-4200-1-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Abhinav Kumar &lt;quic_abhinavk@quicinc.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: Always clear mask bits to disable interrupts at dp_ctrl_reset_irq_ctrl()</title>
<updated>2022-06-29T07:03:30+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2022-05-17T16:21:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=93f7d2a7fcf33e77285db44b512eb5a8e4657fe7'/>
<id>urn:sha1:93f7d2a7fcf33e77285db44b512eb5a8e4657fe7</id>
<content type='text'>
commit 993a2adc6e2e94a0a7b5bfc054eda90ac95f62c3 upstream.

dp_catalog_ctrl_reset() will software reset DP controller. But it will
not reset programmable registers to default value. DP driver still have
to clear mask bits to interrupt status registers to disable interrupts
after software reset of controller.

At current implementation, dp_ctrl_reset_irq_ctrl() will software reset dp
controller but did not call dp_catalog_ctrl_enable_irq(false) to clear hpd
related interrupt mask bits to disable hpd related interrupts due to it
mistakenly think hpd related interrupt mask bits will be cleared by software
reset of dp controller automatically. This mistake may cause system to crash
during suspending procedure due to unexpected irq fired and trigger event
thread to access dp controller registers with controller clocks are disabled.

This patch fixes system crash during suspending problem by removing "enable"
flag condition checking at dp_ctrl_reset_irq_ctrl() so that hpd related
interrupt mask bits are cleared to prevent unexpected from happening.

Changes in v2:
-- add more details commit text

Changes in v3:
-- add synchrons_irq()
-- add atomic_t suspended

Changes in v4:
-- correct Fixes's commit ID
-- remove synchrons_irq()

Changes in v5:
-- revise commit text

Changes in v6:
-- add event_lock to protect "suspended"

Changes in v7:
-- delete "suspended" flag

Fixes: 989ebe7bc446 ("drm/msm/dp: do not initialize phy until plugin interrupt received")
Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Patchwork: https://patchwork.freedesktop.org/patch/486591/
Link: https://lore.kernel.org/r/1652804494-19650-1-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Abhinav Kumar &lt;quic_abhinavk@quicinc.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: force link training for display resolution change</title>
<updated>2022-06-29T07:03:24+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2022-06-16T20:26:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=e24709e89b1b0840647ddbdd7d9e129ba8d47904'/>
<id>urn:sha1:e24709e89b1b0840647ddbdd7d9e129ba8d47904</id>
<content type='text'>
[ Upstream commit a6e2af64a79afa7f1b29375b5231e840a84bb845 ]

Display resolution change is implemented through drm modeset. Older
modeset (resolution) has to be disabled first before newer modeset
(resolution) can be enabled. Display disable will turn off both
pixel clock and main link clock so that main link have to be
re-trained during display enable to have new video stream flow
again. At current implementation, display enable function manually
kicks up irq_hpd_handle which will read panel link status and start
link training if link status is not in sync state.

However, there is rare case that a particular panel links status keep
staying in sync for some period of time after main link had been shut
down previously at display disabled. In this case, main link retraining
will not be executed by irq_hdp_handle(). Hence video stream of newer
display resolution will fail to be transmitted to panel due to main
link is not in sync between host and panel.

This patch will bypass irq_hpd_handle() in favor of directly call
dp_ctrl_on_stream() to always perform link training in regardless of
main link status. So that no unexpected exception resolution change
failure cases will happen. Also this implementation are more efficient
than manual kicking off irq_hpd_handle function.

Changes in v2:
-- set force_link_train flag on DP only (is_edp == false)

Changes in v3:
-- revise commit  text
-- add Fixes tag

Changes in v4:
-- revise commit  text

Changes in v5:
-- fix spelling at commit text

Changes in v6:
-- split dp_ctrl_on_stream() for phy test case
-- revise commit text for modeset

Changes in v7:
-- drop 0 assignment at local variable (ret = 0)

Changes in v8:
-- add patch to remove pixel_rate from dp_ctrl

Changes in v9:
-- forward declare dp_ctrl_on_stream_phy_test_report()

Fixes: 62671d2ef24b ("drm/msm/dp: fixes wrong connection state caused by failure of link train")
Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Patchwork: https://patchwork.freedesktop.org/patch/489895/
Link: https://lore.kernel.org/r/1655411200-7255-1-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Rob Clark &lt;robdclark@chromium.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: do not initialize phy until plugin interrupt received</title>
<updated>2022-06-29T07:03:23+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2022-01-18T18:47:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=796d3acd7d9ed88a0309d123f6f6b235136043c5'/>
<id>urn:sha1:796d3acd7d9ed88a0309d123f6f6b235136043c5</id>
<content type='text'>
[ Upstream commit 989ebe7bc4463002c210db0010c8475797a9098f ]

Current DP drivers have regulators, clocks, irq and phy are grouped
together within a function and executed not in a symmetric manner.
This increase difficulty of code maintenance and limited code scalability.
This patch divides the driver life cycle of operation into four states,
resume (including booting up), dongle plugin, dongle unplugged and suspend.
Regulators, core clocks and irq are grouped together and enabled at resume
(or booting up) so that the DP controller is armed and ready to receive HPD
plugin interrupts. HPD plugin interrupt is generated when a dongle plugs
into DUT (device under test). Once HPD plugin interrupt is received, DP
controller will initialize phy so that dpcd read/write will function and
following link training can be proceeded successfully. DP phy will be
disabled after main link is teared down at end of unplugged HPD interrupt
handle triggered by dongle unplugged out of DUT. Finally regulators, code
clocks and irq are disabled at corresponding suspension.

Changes in V2:
-- removed unnecessary dp_ctrl NULL check
-- removed unnecessary phy init_count and power_count DRM_DEBUG_DP logs
-- remove flip parameter out of dp_ctrl_irq_enable()
-- add fixes tag

Changes in V3:
-- call dp_display_host_phy_init() instead of dp_ctrl_phy_init() at
        dp_display_host_init() for eDP

Changes in V4:
-- rewording commit text to match this commit changes

Changes in V5:
-- rebase on top of msm-next branch

Changes in V6:
-- delete flip variable

Changes in V7:
-- dp_ctrl_irq_enable/disabe() merged into dp_ctrl_reset_irq_ctrl()

Changes in V8:
-- add more detail comment regrading dp phy at dp_display_host_init()

Changes in V9:
-- remove set phy_initialized to false when -ECONNRESET detected

Changes in v10:
--  group into one series

Changes in v11:
-- drop drm/msm/dp: dp_link_parse_sink_count() return immediately
	if aux read

Changes in v12:
-- move dp_display_host_phy_exit() after dp_display_host_deinit()

Changes in v13:
-- do not execute phy_init until plugged_in interrupt for edp, same as DP.

Changes in v14:
-- remove redundant dp-&gt;core_initialized = false form dp_pm_suspend.

Changes in v15:
-- remove core_initialized flag check at both host_init and host_deinit

Changes in v16:
-- remove dp_display_host_phy_exit core_initialized=false at dp_pm_suspend

Changes in v17:
-- remove core_initialized checking before execute attention_cb()

Changes in v18:
-- remove core_initialized checking at dp_pm_suspend

Fixes: 8ede2ecc3e5e ("drm/msm/dp: Add DP compliance tests on Snapdragon Chipsets")
Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Link: https://lore.kernel.org/r/1642531648-8448-2-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: do not stop transmitting phy test pattern during DP phy compliance test</title>
<updated>2022-06-09T08:22:52+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2022-04-26T17:58:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=f7e3daef5e2324e2164e2610ed273e52d3bf0c61'/>
<id>urn:sha1:f7e3daef5e2324e2164e2610ed273e52d3bf0c61</id>
<content type='text'>
[ Upstream commit 2788b4efa60c1e03ac10a156f3fdbd3be0f9198c ]

At normal operation, transmit phy test pattern has to be terminated before
DP controller switch to video ready state. However during phy compliance
testing, transmit phy test pattern should not be terminated until end of
compliance test which usually indicated by unplugged interrupt.

Only stop sending the train pattern in dp_ctrl_on_stream() if we're not
doing compliance testing. We also no longer reset 'p_level' and
'v_level' within dp_ctrl_on_link() due to both 'p_level' and 'v_level'
are acquired from link status at previous dpcd read and we like to use
those level to start link training.

Changes in v2:
-- add more details commit text
-- correct Fixes

Changes in v3:
-- drop unnecessary braces

Fixes: 2e0adc765d88 ("drm/msm/dp: do not end dp link training until video is ready")
Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Patchwork: https://patchwork.freedesktop.org/patch/483564/
Link: https://lore.kernel.org/r/1650995939-28467-3-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: reset DP controller before transmit phy test pattern</title>
<updated>2022-06-09T08:22:52+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2022-04-26T17:58:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=bac5ff8594cb40941e69d6cc0c2659de133778b5'/>
<id>urn:sha1:bac5ff8594cb40941e69d6cc0c2659de133778b5</id>
<content type='text'>
[ Upstream commit 581d69981159b00f0443d171a4b900089f34ccfe ]

DP controller state can not switch from video ready state to
transmit phy pattern state at run time. DP mainlink has to be
teared down followed by reset controller to default state to have
DP controller switch to transmit phy test pattern state and start
generate specified phy test pattern to sinker once main link setup
again.

Changes in v2:
-- correct Fixes's commit id

Fixes: 52352fe2f866 ("drm/msm/dp: use dp_ctrl_off_link_stream during PHY compliance test run")
Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Patchwork: https://patchwork.freedesktop.org/patch/483563/
Link: https://lore.kernel.org/r/1650995939-28467-2-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: stop link training after link training 2 failed</title>
<updated>2022-04-08T12:23:32+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2022-01-18T18:47:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=740d2330760e710240c9d89e191686a1d148dda2'/>
<id>urn:sha1:740d2330760e710240c9d89e191686a1d148dda2</id>
<content type='text'>
[ Upstream commit 9051d629dbf7a998a40f7eac65a9512b01bc3bb8 ]

Each DP link training contains link training 1 followed by link
training 2.  There is maximum of 5 retries of DP link training
before declared link training failed. It is required to stop link
training at end of link training 2 if it is failed so that next
link training 1 can start freshly. This patch fixes link compliance
test  case 4.3.1.13 (Source Device Link Training EQ Fallback Test).

Changes in v10:
--  group into one series

Changes in v11:
-- drop drm/msm/dp: dp_link_parse_sink_count() return immediately if aux read

Fixes: 2e0adc765d88 ("drm/msm/dp: do not end dp link training until video is ready")
Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Link: https://lore.kernel.org/r/1642531648-8448-5-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: do not end dp link training until video is ready</title>
<updated>2021-08-10T21:49:54+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>khsieh@codeaurora.org</email>
</author>
<published>2021-08-05T20:44:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=2e0adc765d884cc080baa501e250bfad97035b09'/>
<id>urn:sha1:2e0adc765d884cc080baa501e250bfad97035b09</id>
<content type='text'>
Initialize both pre-emphasis and voltage swing level to 0 before
start link training and do not end link training until video is
ready to reduce the period between end of link training and video
start to meet Link Layer CTS requirement.  Some dongle main link
symbol may become unlocked again if host did not end link training
soon enough after completion of link training 2. Host have to re
train main link if loss of symbol locked detected before end link
training so that the coming video stream can be transmitted to sink
properly. This fixes Link Layer CTS cases 4.3.2.1, 4.3.2.2, 4.3.2.3
and 4.3.2.4.

Changes in v3:
-- merge retrain link if loss of symbol locked happen into this patch
-- replace dp_ctrl_loss_symbol_lock() with dp_ctrl_channel_eq_ok()

Signed-off-by: Kuogee Hsieh &lt;khsieh@codeaurora.org&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Link: https://lore.kernel.org/r/1628196295-7382-7-git-send-email-khsieh@codeaurora.org
Signed-off-by: Rob Clark &lt;robdclark@chromium.org&gt;
</content>
</entry>
</feed>
