[PATCH v1] arm: global_data: add scmi pointer

[Simon Glass]

Hi Peng,

On Mon, 7 Oct 2024 at 20:59, Peng Fan <peng.fan at nxp.com> wrote:
>
> > Subject: Re: [PATCH v1] arm: global_data: add scmi pointer
> >
> > On Sun, Oct 06, 2024 at 05:52:28PM +0800, alice.guo at oss.nxp.com
> > wrote:
> > > From: Peng Fan <peng.fan at nxp.com>
> > >
> > > Add scmi device and channel pointer for i.MX9.
> > >
> > > Signed-off-by: Peng Fan <peng.fan at nxp.com>
> > > Signed-off-by: Alice Guo <alice.guo at nxp.com>
> > > Reviewed-by: Ye Li <ye.li at nxp.com>
> > > ---
> > >  arch/arm/include/asm/global_data.h | 3 +++
> > >  1 file changed, 3 insertions(+)
> > >
> > > diff --git a/arch/arm/include/asm/global_data.h
> > > b/arch/arm/include/asm/global_data.h
> > > index 45401d5e3c..d04359f167 100644
> > > --- a/arch/arm/include/asm/global_data.h
> > > +++ b/arch/arm/include/asm/global_data.h
> > > @@ -108,6 +108,9 @@ struct arch_global_data {  #ifdef
> > CONFIG_SMBIOS
> > >     ulong smbios_start;             /* Start address of SMBIOS
> > table */
> > >  #endif
> > > +#if defined(CONFIG_SCMI_FIRMWARE) && defined(CONFIG_IMX9)
> > > +   struct udevice *scmi_dev;
> > > +#endif
> > >  };
> > >
> > >  #include <asm-generic/global_data.h>
> >
> > But why is this only needed for i.MX9 families and not other users?
>
> i.MX95 has some code that communicates with SCMI platform,
> but no scmi driver for those code, saying rom pass info. So we need
> a global scmi_dev.

Would it be OK to find the device using uclass_first_device(UCLASS_SMCI) ?

i.e. can we do without a pointer in global_data ?

If we do need it, I think it is better to have the condition just be
SCMI_FIRMWARE (and live with the extra 8 bytes in global_data). We
really should not have SoC-specific options in global_data, or even
drivers for that matter.

Regards,
Simon
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