Re: [Qemu-devel] [PATCH v4 14/17] spapr_pci: populate DRC dt entries for PHBs

[Michael Roth <mdroth@linux.vnet.ibm.com>]

Quoting David Gibson (2015-01-18 23:22:54)
> On Tue, Dec 23, 2014 at 06:30:28AM -0600, Michael Roth wrote:
> > Reserve 32 entries of type PCI in each PHB's initial FDT. This
> > advertises to guests that each PHB is DR-capable device with
> > physical hotpluggable slots. This is necessary for allowing
> > hotplugging of devices to it later via bus rescan or guest rpaphp
> > hotplug module.
> > 
> > Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
> > ---
> >  hw/ppc/spapr_pci.c | 9 ++++++++-
> >  1 file changed, 8 insertions(+), 1 deletion(-)
> > 
> > diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
> > index 73e86a4..a5d7791 100644
> > --- a/hw/ppc/spapr_pci.c
> > +++ b/hw/ppc/spapr_pci.c
> > @@ -47,6 +47,8 @@
> >  #define RTAS_TYPE_MSI           1
> >  #define RTAS_TYPE_MSIX          2
> >  
> > +#define FDT_MAX_SIZE            0x10000
> 
> This define doesn't appear to be used in the new code.
> 
> >  #include "hw/ppc/spapr_drc.h"
> >  
> >  static sPAPRPHBState *find_phb(sPAPREnvironment *spapr, uint64_t buid)
> > @@ -872,7 +874,7 @@ int spapr_populate_pci_dt(sPAPRPHBState *phb,
> >                            uint32_t xics_phandle,
> >                            void *fdt)
> >  {
> > -    int bus_off, i, j;
> > +    int bus_off, i, j, ret;
> >      char nodename[256];
> >      uint32_t bus_range[] = { cpu_to_be32(0), cpu_to_be32(0xff) };
> >      struct {
> > @@ -951,6 +953,11 @@ int spapr_populate_pci_dt(sPAPRPHBState *phb,
> >      object_child_foreach(OBJECT(phb), spapr_phb_children_dt,
> >                           &((sPAPRTCEDT){ .fdt = fdt, .node_off = bus_off }));
> >  
> > +    ret = spapr_drc_populate_dt(fdt, bus_off, SPAPR_DR_CONNECTOR_TYPE_PCI);
> 
> AFAICT this will add information for all PCI connectors in the
> system.  Shouldn't it only add the ones belonging to this PHB?

Argh, yes indeed. Since we pass in the parent device during
spapr_dr_connector_new() I think I can simply have this pass in the parent PHB
we want to generate entries for as a filter. Will add this for v5 and do some
testing with multiple PHBs.

> 
> -- 
> David Gibson                    | I'll have my music baroque, and my code
> david AT gibson.dropbear.id.au  | minimalist, thank you.  NOT _the_ _other_
>                                 | _way_ _around_!
> http://www.ozlabs.org/~dgibson