Re: [PATCH 3/7] hw/ppc: Handle stash command in PowerNV SBE

[Aditya Gupta]

On 11/03/25 10:20, Harsh Prateek Bora wrote:

> > <...snip...>
> >
> > --- a/hw/ppc/pnv_sbe.c
> > +++ b/hw/ppc/pnv_sbe.c
> > @@ -82,6 +82,8 @@
> >   #define SBE_CONTROL_REG_S0              PPC_BIT(14)
> >   #define SBE_CONTROL_REG_S1              PPC_BIT(15)
> >   +static uint64_t mpipl_skiboot_base = 0x30000000 /*default 
> > SKIBOOT_BASE*/;
> > +
> >   static void pnv_sbe_set_host_doorbell(PnvSBE *sbe, uint64_t val)
> >   {
> >       val &= SBE_HOST_RESPONSE_MASK; /* Is this right? What does HW 
> > do? */
> > @@ -281,6 +283,29 @@ static void do_sbe_msg(PnvSBE *sbe)
> >               timer_del(sbe->timer);
> >           }
> >           break;
> > +    case SBE_CMD_STASH_MPIPL_CONFIG:
> > +        /* key = sbe->mbox[1] */
> > +        switch (sbe->mbox[1]) {
> > +        case SBE_STASH_KEY_SKIBOOT_BASE:
> > +            mpipl_skiboot_base = sbe->mbox[2];
> > +            qemu_log_mask(LOG_UNIMP,
> > +                "Stashing skiboot base: 0x%lx\n", mpipl_skiboot_base);
> > +
> > +            /*
> > +             * Set the response register.
> > +             *
> > +             * Currently setting the same sequence number in
> > +             * response as we got in the request.
> > +             */
> > +            sbe->mbox[4] = sbe->mbox[0];    /* sequence number */
> > +            pnv_sbe_set_host_doorbell(sbe,
> > +                    sbe->host_doorbell | SBE_HOST_RESPONSE_WAITING);
> > +
> > +            break;
> > +        default:
> > +            qemu_log_mask(LOG_UNIMP, "SBE Unimplemented command: 
> > 0x%x\n", cmd);
>
> Unimplemented SBE_CMD_STASH_MPIPL_CONFIG key ?

Got it. Thanks for the reword suggestion, will do it.


Thanks,

- Aditya G

> > +        }
> > +        break;
> >       default:
> >           qemu_log_mask(LOG_UNIMP, "SBE Unimplemented command: 
> > 0x%x\n", cmd);
> >       }
> > diff --git a/include/hw/ppc/pnv_sbe.h b/include/hw/ppc/pnv_sbe.h
> > index b6b378ad14c7..f6cbcf990ed9 100644
> > --- a/include/hw/ppc/pnv_sbe.h
> > +++ b/include/hw/ppc/pnv_sbe.h
> > @@ -53,4 +53,7 @@ struct PnvSBEClass {
> >       const MemoryRegionOps *xscom_mbox_ops;
> >   };
> >   +/* Helper to access stashed SKIBOOT_BASE */
> > +bool pnv_sbe_mpipl_skiboot_base(void);
> > +
> >   #endif /* PPC_PNV_SBE_H */