[PATCH v2] powerpc/powernv: Add ultravisor message log interface

[Claudio Carvalho]

On 8/23/19 9:48 AM, Michael Ellerman wrote:
> Hi Claudio,

Hi Michael,

>
> Claudio Carvalho <cclaudio at linux.ibm.com> writes:
>> Ultravisor (UV) provides an in-memory console which follows the OPAL
>> in-memory console structure.
>>
>> This patch extends the OPAL msglog code to also initialize the UV memory
>> console and provide a sysfs interface (uv_msglog) for userspace to view
>> the UV message log.
>>
>> CC: Madhavan Srinivasan <maddy at linux.vnet.ibm.com>
>> CC: Oliver O'Halloran <oohall at gmail.com>
>> Signed-off-by: Claudio Carvalho <cclaudio at linux.ibm.com>
>> ---
>> This patch depends on the "kvmppc: Paravirtualize KVM to support
>> ultravisor" patchset submitted by Claudio Carvalho.
>> ---
>>  arch/powerpc/platforms/powernv/opal-msglog.c | 99 ++++++++++++++------
>>  1 file changed, 72 insertions(+), 27 deletions(-)
> I think the code changes look mostly OK here.
>
> But I'm not sure about the end result in sysfs.
>
> If I'm reading it right this will create:
>
>  /sys/firmware/opal/uv_msglog
>
> Which I think is a little weird, because the UV is not OPAL.
>
> So I guess I wonder if the file should be created elsewhere to avoid any
> confusion and keep things nicely separated.
>
> Possibly /sys/firmware/ultravisor/msglog ?


Yes, makes sense. I will do that.

Currently, the ultravisor memory console DT property is in
/ibm,opal/ibm,opal-uv-memcons. I think we should move it to
/ibm,ultravisor/ibm,uv-firmware/ibm,uv-memcons. What do you think?

Thanks,
Claudio


>
> cheers