lkml.org 
[lkml]   [2020]   [Jun]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 2/2] coresight: tmc: Add shutdown callback for TMC ETR/ETF
Hi Robin,

On 2020-06-03 17:51, Robin Murphy wrote:
> On 2020-06-03 13:00, Sai Prakash Ranjan wrote:
>> Hi Robin, Mathieu
>>
>> On 2020-06-03 17:07, Robin Murphy wrote:
>>> On 2020-06-01 22:28, Mathieu Poirier wrote:
>>>> That being said I'm sure that dependencies on an IOMMU isn't a
>>>> problem confined
>>>> to coresight. I am adding Robin Murphy, who added this commit [1],
>>>> to the thread
>>>> in the hope that he can provide guidance on the right way to do
>>>> this.
>>>
>>> Right, it's not specific to CoreSight, and it's not even specific to
>>> IOMMUs really. In short, blame kexec ;)
>>>
>>
>> Yes it is not specific to coresight, we are targeting this for all
>> consumers/clients of SMMU(atleast on SC7180 SoC). We have display
>> throwing
>> NoC/interconnect errors[1] during reboot after SMMU is disabled.
>> This is also not specific to kexec either as you explained here [2]
>> about
>> a case with display which is exacly what is happening in our system
>> [1].
>
> Sure, but those instances are begging the question of why the SMMU is
> disabled at reboot in the first place ;)
>

That is what happens in SMMU shutdown callback right? It is the
reboot/shutdown
flow.

arm_smmu_device_shutdown()
platform_drv_shutdown()
device_shutdown()
kernel_restart_prepare()
kernel_restart()

Thanks,
Sai

--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a
member
of Code Aurora Forum, hosted by The Linux Foundation

\
 
 \ /
  Last update: 2020-06-03 14:26    [W:0.065 / U:0.544 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site