[PATCH] Revert "drm/msm/dp: Remove INIT_SETUP delay"

[Dmitry Baryshkov]

On 08/05/2023 14:02, Leonard Lausen wrote:
> Abhinav Kumar <quic_abhinavk at quicinc.com> writes:
>> On 5/7/2023 7:15 PM, Bjorn Andersson wrote:
>>> When booting with the cable connected on my X13s, 100 is long enough for
>>> my display to time out and require me to disconnect and reconnect the
>>> cable again.
>>>
>>> Do we have any idea of why the reduction to 0 is causing an issue when
>>> using the internal HPD?
>>>
>>> Regards,
>>> Bjorn
>> Yes, we do know why this is causing an issue. The cleaner patch for this
>> will be posted this week.
> 
> Great!
> 
>> There is no need to add the 100ms delay back yet.
>>
>> thanks for posting this but NAK on this patch till we post the fix this
>> week.
>>
>> Appreciate a bit of patience till then.
> 
> This regression is already part of the 6.3 stable release series. Will
> the new patch qualify for inclusion in 6.3.y? Or will it be part of 6.4
> and this revert should go into 6.3.y?

This is a tough situation, as landing a revert will break x13s, as noted 
by Bjorn. Given that the workaround is known at this moment, I would 
like to wait for the patch from Abhinav to appear, then we can decide 
which of the fixes should go to the stable kernel.

> 
> Even with this revert, there are additional regressions in 6.3 causing
> dpu errors and blank external display upon suspending and resuming the
> system while an external display is connected. Will your new patch also
> fix these regressions?
> 
> [  275.025497] [drm:dpu_encoder_phys_vid_wait_for_commit_done:488] [dpu error]vblank timeout
> [  275.025514] [drm:dpu_kms_wait_for_commit_done:510] [dpu error]wait for commit done returned -110
> [  275.064141] [drm:dpu_encoder_frame_done_timeout:2382] [dpu error]enc33 frame done timeout
> 
> followed by a kernel panic if any modification to the display settings
> is done, such as disabling the external display:

Interesting crash, thank you for the report.

> 
> [  341.631287] Hardware name: Google Lazor (rev3 - 8) (DT)
> [  341.631290] pstate: 604000c9 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> [  341.631296] pc : do_raw_spin_unlock+0xb8/0xc4
> [  341.631310] lr : do_raw_spin_unlock+0x78/0xc4
> [  341.631315] sp : ffffffc01100b880
> [  341.631317] x29: ffffffc01100b880 x28: 0000000000000028 x27: 0000000000000038
> [  341.631326] x26: ffffff808c89e180 x25: ffffffef33e39920 x24: 0000000000000000
> [  341.631333] x23: ffffffef33e3ca0c x22: 0000000000000002 x21: ffffff808345ded8
> [  341.631339] x20: ffffff808345ded0 x19: 000000000000001e x18: 0000000000000000
> [  341.631345] x17: 0048000000000460 x16: 0441043b04600438 x15: 04380000089807d0
> [  341.631351] x14: 07b0089807800780 x13: 0000000000000068 x12: 0000000000000001
> [  341.631357] x11: ffffffef3413bb76 x10: 0000000000000bb0 x9 : ffffffef33e3d6bc
> [  341.631363] x8 : ffffff808c89ed90 x7 : ffffff80b1c9f738 x6 : 0000000000000001
> [  341.631370] x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffffff808345def0
> [  341.631375] x2 : 00000000dead4ead x1 : 0000000000000003 x0 : 0000000000000000
> [  341.631383] Kernel panic - not syncing: Asynchronous SError Interrupt
> [  341.631386] CPU: 3 PID: 1520 Comm: kwin_wayland Not tainted 6.3.0-stb-cbq+ #2
> [  341.631390] Hardware name: Google Lazor (rev3 - 8) (DT)
> [  341.631393] Call trace:
> [  341.631395]  dump_backtrace+0xc8/0x104
> [  341.631402]  show_stack+0x20/0x30
> [  341.631407]  dump_stack_lvl+0x48/0x60
> [  341.631414]  dump_stack+0x18/0x24
> [  341.631419]  panic+0x130/0x2fc
> [  341.631425]  nmi_panic+0x54/0x78
> [  341.631428]  arm64_serror_panic+0x74/0x80
> [  341.631434]  arm64_is_fatal_ras_serror+0x6c/0x8c
> [  341.631439]  do_serror+0x48/0x60
> [  341.631444]  el1h_64_error_handler+0x30/0x48
> [  341.631450]  el1h_64_error+0x68/0x6c
> [  341.631455]  do_raw_spin_unlock+0xb8/0xc4
> [  341.631460]  _raw_spin_unlock_irq+0x18/0x38
> [  341.631466]  __wait_for_common+0xb8/0x154
> [  341.631472]  wait_for_completion_timeout+0x28/0x34
> [  341.631477]  dp_ctrl_push_idle+0x3c/0x88
> [  341.631483]  dp_bridge_disable+0x20/0x2c
> [  341.631488]  drm_atomic_bridge_chain_disable+0x8c/0xb8
> [  341.631495]  drm_atomic_helper_commit_modeset_disables+0x198/0x450
> [  341.631501]  msm_atomic_commit_tail+0x1c8/0x36c
> [  341.631507]  commit_tail+0x80/0x108
> [  341.631512]  drm_atomic_helper_commit+0x114/0x118
> [  341.631516]  drm_atomic_commit+0xb4/0xe0
> [  341.631522]  drm_mode_atomic_ioctl+0x6b0/0x890
> [  341.631527]  drm_ioctl_kernel+0xe4/0x164
> [  341.631534]  drm_ioctl+0x35c/0x3bc
> [  341.631539]  vfs_ioctl+0x30/0x50
> [  341.631547]  __arm64_sys_ioctl+0x80/0xb4
> [  341.631552]  invoke_syscall+0x84/0x11c
> [  341.631558]  el0_svc_common.constprop.0+0xc0/0xec
> [  341.631563]  do_el0_svc+0x94/0xa4
> [  341.631567]  el0_svc+0x2c/0x54
> [  341.631570]  el0t_64_sync_handler+0x94/0x100
> [  341.631575]  el0t_64_sync+0x194/0x198
> [  341.631580] SMP: stopping secondary CPUs
> [  341.831615] Kernel Offset: 0x2f2b200000 from 0xffffffc008000000
> [  341.831618] PHYS_OFFSET: 0x80000000
> [  341.831620] CPU features: 0x400000,61500506,3200720b
> [  341.831623] Memory Limit: none

-- 
With best wishes
Dmitry