Re: [PATCH v9 00/12] Support PPTT for ARM64

[Sudeep Holla]

On 29/05/18 11:48, Geert Uytterhoeven wrote:
> Hi Catalin, Jeremy,
> 
> On Thu, May 17, 2018 at 7:05 PM, Catalin Marinas
> <catalin.marinas@xxxxxxx> wrote:
>> On Fri, May 11, 2018 at 06:57:55PM -0500, Jeremy Linton wrote:
>>> Jeremy Linton (12):
>>>   drivers: base: cacheinfo: move cache_setup_of_node()
>>>   drivers: base: cacheinfo: setup DT cache properties early
>>>   cacheinfo: rename of_node to fw_token
>>>   arm64/acpi: Create arch specific cpu to acpi id helper
>>>   ACPI/PPTT: Add Processor Properties Topology Table parsing
>>>   ACPI: Enable PPTT support on ARM64
>>>   drivers: base cacheinfo: Add support for ACPI based firmware tables
>>>   arm64: Add support for ACPI based firmware tables
>>>   arm64: topology: rename cluster_id
>>>   arm64: topology: enable ACPI/PPTT based CPU topology
>>>   ACPI: Add PPTT to injectable table list
>>>   arm64: topology: divorce MC scheduling domain from core_siblings
>>
>> Queued for 4.18 (without Sudeep's latest property_read_u64 cacheinfo
>> patch - http://lkml.kernel.org/r/20180517154701.GA20281@e107155-lin; I
>> can add it separately).
> 
> This is now commit 37c3ec2d810f87ea ("arm64: topology: divorce MC
> scheduling domain from core_siblings") in arm64/for-next/core, causing
> system suspend on big.LITTLE systems to hang after shutting down the first
> CPU:
> 
>     $ echo mem > /sys/power/state
>     PM: suspend entry (deep)
>     PM: Syncing filesystems ... done.
>     Freezing user space processes ... (elapsed 0.001 seconds) done.
>     OOM killer disabled.
>     Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
>     Disabling non-boot CPUs ...
>     CPU1: shutdown
>     psci: CPU1 killed.
> 

Is it OK to assume the suspend failed just after shutting down one CPU
or it's failing during resume ? It depends on whether you had console
disabled or not.

> For me, it fails on the following big.LITTLE systems:
> 
>     R-Car H3 ES2.0 (4xCA57 + 4xCA53)
>     R-Car M3-W (2xCA57 + 4xCA53)
> 

Interesting, is it PSCI based system suspend ?

> System supend still works fine on systems with big cores only:
> 
>     R-Car H3 ES1.0 (4xCA57 (4xCA53 disabled in firmware))
>     R-Car M3-N (2xCA57)
> 
> Reverting this commit fixes the issue for me.
> 

I can't find anything that relates to system suspend in these patches
unless they are messing with something during CPU hot plug-in back
during resume.

-- 
Regards,
Sudeep