[PATCH 1/3] arm64: dts: juno: add coresight support

[Mathieu Poirier]

On 13 June 2016 at 03:18, Sudeep Holla <sudeep.holla at arm.com> wrote:
>
>
> On 12/06/16 22:57, Mathieu Poirier wrote:
>>
>> On 6 June 2016 at 09:59, Sudeep Holla <sudeep.holla at arm.com> wrote:
>>>
>>> Most of the debug-related components on Juno are located in the coreSight
>>> subsystem while others are located in the Cortex-Axx clusters, the SCP
>>> subsystem, and in the main system.
>>>
>>> Each core in the two processor clusters contain an Embedded Trace
>>> Macrocell(ETM) which generates real-time trace information that trace
>>> tools can use and an ATB trace output that is sent to a funnel before
>>> going to the CoreSight subsystem.
>>>
>>> The trace output signals combine with two trace expansions using another
>>> funnel and fed into the Embedded Trace FIFO(ETF0).
>>>
>>> The output trace data stream of the funnel is then replicated before it
>>> is sent to either the:
>>> - Trace Port Interface Unit(TPIU), that sends it out using the trace
>>> port.
>>> - ETR that can write the trace data to memory located in the application
>>>    memory space
>>
>>
>> Hi Sudeep,
>>
>> Did you try booting this on juno-r0?  On my side the system won't boot
>> unless I enable the debug power domain by externally connecting to the
>> system using DS-5.
>>
>
> As you have already realized that you need SCPI power domain patches for
> the functionality. However, in absence of those patches or when it's
> disabled, it shouldn't cause any boot or runtime issues. Only ETM or
> coresight won't work. If it's causing any crash or hang, please do let
> me know, that needs to be fixed. I have only tested with latest
> firmware. Let me know the details of hang/crash and firmware version you
> are using.

We have a problem then.  Booting with this branch[1] and the 3 DT
patches from this set the system hangs.  But before going any further
I'd bet the FW on my board is too old.  This is what I get on my side:

RM V2M-Juno Boot loader v1.0.0
HBI0262 build 1684

ARM V2M_Juno Firmware v1.3.4
Build Date: Aug 27 2015

Time :  14:44:50
Date :  13:06:2016

Press Enter to stop auto boot...

What version are you using?

In the mean time I'm digging up your SCPI patches...

Thanks,
Mathieu

[1]. https://git.linaro.org/kernel/coresight.git/ (branch next)


>
> --
> Regards,
> Sudeep