Re: [PATCH] firmware: arm_scmi: fix psci dependency

[Sudeep Holla]

On Tue, May 05, 2020 at 04:04:21PM +0100, Sudeep Holla wrote:
> Hi Arnd,
>
> On Tue, May 05, 2020 at 04:08:08PM +0200, Arnd Bergmann wrote:
> > When CONFIG_ARM_PSCI_FW is disabled but CONFIG_HAVE_ARM_SMCCC is enabled,
> > arm-scmi runs into a link failure:
> >
> > arm-linux-gnueabi-ld: drivers/firmware/arm_scmi/smc.o: in function `smc_send_message':
> > smc.c:(.text+0x200): undefined reference to `arm_smccc_1_1_get_conduit'
> >
> > Use an inline helper to default to version v1.0 in the absence of psci.
> >
>
> Thanks for fixing this. I was thinking if we can separate PSCI and SMCCC
> quickly as a fix for this but I think he needs to be discussed in detail.
>
> I am fine with this fix as is and happy to apply to my tree if no one
> objects.
>
> Sorry but taking this patch as opportunity to discuss how to carry the
> dependency in future. Just a proposal,
>
> 1. Introduce a DT node for SMCCC v1.2+

Sorry for the confusion and the above note might have scared people.
Also I misunderstood some internal discussions we had as part of my
SMCCC SOC_ID series[1]. I realised(rather Mark made me realise) this
SCMI SMC is kind of dependent on PSCI as we reuse the conduit from there.
So for now I will make it depend on PSCI to fix the build temporarily.

Also I will try to work out if we can move HAVE_ARCH_SMCCC to something
like HAVE_ARCH_RAW_SMCCC and use HAVE_ARCH_SMCCC for newer changes that
depend on PSCI for probing and conduit. The legacy SMCCC can then go under
HAVE_ARCH_RAW_SMCCC. This was Mark's suggestion, I will try to work it
out and may be post it as part of my SMCCC SOC_ID series also moving
code under drivers/firmware/smccc

--
Regards,
Sudeep

[1] https://lore.kernel.org/r/20200504092905.10580-1-sudeep.holla@xxxxxxx