Re: [Qemu-devel] [PATCH v3 15/19] spapr_xive: Cache device tree nodename in sPAPRXive

[Greg Kurz <groug@kaod.org>]

On Fri, 18 Jan 2019 14:38:31 +0100
Cédric Le Goater <clg@kaod.org> wrote:

> On 1/17/19 6:16 PM, Greg Kurz wrote:
> > PHB hotplug will need to know the name of the XIVE controller node. Since
> > it is an invariant for the machine lifetime, compute it at realize and
> > store it under the sPAPRXive structure.  
> Could you please gather all these changes [15-17] in one patch. It would 
> be easier to track. 
> 

I'll do that in v4.

> > Signed-off-by: Greg Kurz <groug@kaod.org>
> > ---
> >  hw/intc/spapr_xive.c        |    9 ++++-----
> >  include/hw/ppc/spapr_xive.h |    3 +++
> >  2 files changed, 7 insertions(+), 5 deletions(-)
> > 
> > diff --git a/hw/intc/spapr_xive.c b/hw/intc/spapr_xive.c
> > index e542ae59d7fd..9732c3d89c77 100644
> > --- a/hw/intc/spapr_xive.c
> > +++ b/hw/intc/spapr_xive.c
> > @@ -316,6 +316,9 @@ static void spapr_xive_realize(DeviceState *dev, Error **errp)
> >      /* Map all regions */
> >      spapr_xive_map_mmio(xive);
> >  
> > +    xive->nodename = g_strdup_printf("interrupt-controller@%" PRIx64,
> > +                           xive->tm_base + XIVE_TM_USER_PAGE * (1 << TM_SHIFT));  
> 
> I would use a helper routine instead.
>  

Ok, I see your suggestion to put the name in a static. Well, it would work
as long as we only have one interrupt controller around. It is the case now
but could this change in the future ? If not then I'm perfectly fine with
your suggestions, otherwise I guess the nodename should be under sPAPRXive.

> >      qemu_register_reset(spapr_xive_reset, dev);
> >  }
> >  
> > @@ -1436,7 +1439,6 @@ int spapr_dt_xive(sPAPRMachineState *spapr, uint32_t nr_servers, void *fdt)
> >          cpu_to_be32(7),    /* start */
> >          cpu_to_be32(0xf8), /* count */
> >      };
> > -    gchar *nodename;
> >  
> >      /*
> >       * The "ibm,plat-res-int-priorities" property defines the priority
> > @@ -1453,10 +1455,7 @@ int spapr_dt_xive(sPAPRMachineState *spapr, uint32_t nr_servers, void *fdt)
> >                             XIVE_TM_OS_PAGE * (1ull << TM_SHIFT));
> >      timas[3] = cpu_to_be64(1ull << TM_SHIFT);
> >  
> > -    nodename = g_strdup_printf("interrupt-controller@%" PRIx64,
> > -                           xive->tm_base + XIVE_TM_USER_PAGE * (1 << TM_SHIFT));
> > -    _FDT(node = fdt_add_subnode(fdt, 0, nodename));
> > -    g_free(nodename);
> > +    _FDT(node = fdt_add_subnode(fdt, 0, xive->nodename));  
> 
> and use the helper routine here.
> 
> >      _FDT(fdt_setprop_string(fdt, node, "device_type", "power-ivpe"));
> >      _FDT(fdt_setprop(fdt, node, "reg", timas, sizeof(timas)));
> > diff --git a/include/hw/ppc/spapr_xive.h b/include/hw/ppc/spapr_xive.h
> > index 29dafead9ba0..deea34b03ee5 100644
> > --- a/include/hw/ppc/spapr_xive.h
> > +++ b/include/hw/ppc/spapr_xive.h
> > @@ -26,6 +26,9 @@ typedef struct sPAPRXive {
> >      XiveENDSource end_source;
> >      hwaddr        end_base;
> >  
> > +    /* DT */
> > +    gchar *nodename;  
> 
> I don't think this is needed. See other patches for why.
> 
> Thanks,
> 
> C.
>  
> >
> >      /* Routing table */
> >      XiveEAS       *eat;
> >      uint32_t      nr_irqs;
> >   
>