On Mon, 18 Jun 2018 13:31:26 +0200 Cédric Le Goater <c...@kaod.org> wrote:
> On 06/18/2018 11:54 AM, Greg Kurz wrote: > > On Mon, 18 Jun 2018 10:56:55 +0200 > > Cédric Le Goater <c...@kaod.org> wrote: > > > >> [ ... ] > >> > >>>>> This is 4 irqs per PHB, hence up to 32 PHBs. Cool, we're currently > >>>>> limited to 31 PHBs. > >>>>> > >>>>>> +#define SPAPR_IRQ_MSI 0x1100 /* Offset of the dynamic range > >>>>>> covered > >>>>> > >>>>> We only support dynamic MSIs with PCI, maybe rename to > >>>>> SPAPR_IRQ_PCI_MSI ? > >>>> > >>>> hmm, no. We could have CAPI devices there. remember ? ;) > >>>> > >>> > >>> Well... OpenCAPI devices are exposed to the OS as PCI devices, so I'm not > >>> sure we need a CAPI specific range. > >> > >> yes. so this range is common to all devices doing dynamic allocation > >> of IRQs. How should we call it ? > >> > >>>>>> + * by the bitmap allocator */ > >>>>>> > >>>>> > >>>>> The range size is hence 1k (XICS_IRQS_SPAPR) for the time being. > >>>> > >>>> in fact we could this bogus limit and use spapr->irq_map_nr now. > >>>> > >>> > >>> "we could *missing verb* this bogus limit"... so I'm not sure to > >>> understand... > >> > >> oups. We could use spapr->irq_map_nr instead of XICS_IRQS_SPAPR when > >> defining : > >> > >> _FDT(fdt_setprop_cell(fdt, bus_off, "ibm,pe-total-#msi", > >> XICS_IRQS_SPAPR)); > >> > >> in spapr_pci.c > >> > > > > Ah... yeah, I've always found weird that all PHBs advertise the same number > > of available MSIs as the total number of irqs for the whole machine. And > > putting spapr->irq_map_nr looks weird all the same if all PHBs rely on the > > same bitmap actually. > > > > I'm thinking of doing the other way around: keep XICS_IRQS_SPAPR in > > "ibm,pe-total-#msi" and have one XICS_IRQS_SPAPR sized bitmap per PHB. > > That could be the place where to put the msi allocator. > Are you suggesting to move @irq_map and @irq_map_nr to sPAPRPHBState and to have these setup during PHB realize ? I guess we could do that. > C.
