On Tue, Apr 19, 2016 at 02:16:42PM +1000, Alexey Kardashevskiy wrote: >On 02/17/2016 02:44 PM, Gavin Shan wrote: >>Currently, the PEs and their associated resources are assigned >>in ppc_md.pcibios_fixup() except those used by SRIOV VFs. > >But this new code does not affect IOV and VF's PEs will still be created >somewhere else rather than pnv_pci_setup_bridge()? > Correct. VF PEs cannot be created in pnv_pci_setup_bridge() as the PF's IOV capability isn't enabled at that point. > >>The >>function is called for once after PCI probing and resources >>assignment is completed. So it isn't hotplug friendly. >> >>This creates PEs dynamically by ppc_md.pcibios_setup_bridge(), which >>is called on the event during system bootup and PCI hotplug: updating >>PCI bridge's windows after resource assignment/reassignment are done. >>For partial hotplug case, where not all PCI devices belonging to the >>PE are unplugged and plugged again, we just need unbinding/binding >>the affected PCI devices with the corresponding PE without creating >>new one. >> >>As there is no upstream bridge for root bus that needs to be covered >>by PE, we have to create PE for root bus in ppc_md.pcibios_setup_bridge() >>before any other PEs can be created, as PE for root bus is the ancestor >>to anyone else. > >We did not need a root bus PE before? What is the other PE reserved for? >Comments only say "reserved"... > No, A PE for root bus is needed before. other PEs can be for the PCI bus originated from root port and the subordinate domains. >> >>Also, the windows of root port or the upstream port of PCIe switch behind >>root port are extended to be PHB's apertures to accommodate the additional >>resources needed by newly plugged devices based on the fact: hotpluggable >>slot is behind root port or downstream port of the PCIe switch behind >>root port. The extension for those PCI brdiges' windows is done in >>ppc_md.pcibios_setup_bridge() as well. > > >This patch seems to be doing way too many things, hard to follow. > >Could you please split the patch into smaller chunks? For example (you can do >it totally different): >- move pnv_pci_ioda_setup_opal_tce_kill() >- move PE creation from pnv_pci_ioda_fixup() to pnv_pci_setup_bridge(); >- add pnv_pci_fixup_bridge_resources() >- add an extra reserved PE for the root bus (and all this magic with >root_pe_idx/root_pe_populated) >- ... > I'll evaluate it later. It's always nice to have small patches. Thanks for the comments. > > > >-- >Alexey > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
