On 19 April 2017 at 09:47, Michael Ellerman <mpe@xxxxxxxxxxxxxx> wrote: > Bjorn Helgaas <bhelgaas@xxxxxxxxxx> writes: > >> On Mon, Apr 17, 2017 at 4:36 PM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote: >>> From: Yongji Xie <elohimes@xxxxxxxxx> >>> diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c >>> index 6901a06da2f9..b724487cbd0f 100644 >>> --- a/arch/powerpc/platforms/powernv/pci-ioda.c >>> +++ b/arch/powerpc/platforms/powernv/pci-ioda.c >>> @@ -3287,6 +3287,11 @@ static void pnv_pci_setup_bridge(struct pci_bus *bus, unsigned long type) >>> } >>> } >>> >>> +static resource_size_t pnv_pci_default_alignment(struct pci_dev *pdev) >>> +{ >>> + return PAGE_SIZE; >>> +} >> >> Is it necessary that pcibios_default_alignment() take a pci_dev >> pointer? > > It's not necessary given the current implementation, obviously. > > But it did strike me as a good idea to pass it in case we ever want to > do anything device specific in future. > >> I'd like this better if it were: >> >> resource_size_t pcibios_default_alignment(void) { ... } >> >> because the last patch relies on the assumption that all resources of >> *all* devices will be realigned to the same alignment. > > But I guess that precludes doing anything device specific, at least > without further changes. So in that case it would be better if the API > didn't include the pci_dev. > > Hopefully Yongji can confirm that there were no plans to use the > pci_dev in future patches. > Yes, seems like pci_dev pointer doesn't match the assumption that all resources will be realigned to the same alignment. It's OK to me to remove it. Thanks, Yongji