Hi Guenter, On Wed, Jul 22, 2015 at 03:22:57PM +0100, Guenter Roeck wrote: > On 07/22/2015 02:14 AM, Lorenzo Pieralisi wrote: > > Bjorn, Guenter, > > > > On Thu, Jul 09, 2015 at 11:59:16AM +0100, Lorenzo Pieralisi wrote: > >> When a PCI bus is scanned, upon PCI bridge detection the kernel > >> has to read the bridge registers to set-up its resources so that > >> the PCI resource hierarchy can be validated properly. > >> > >> Most if not all architectures read PCI bridge registers in the > >> pcibios_fixup_bus hook, that is called by the PCI generic layer > >> whenever a PCI bus is scanned. > >> > >> Since pci_read_bridge_bases is an arch agnostic operation (and it > >> is carried out on all architectures) it can be moved to the generic > >> PCI layer in order to consolidate code and remove the respective > >> calls from the architectures back-ends. > >> > >> The PCI_PROBE_ONLY flag is not checked before calling > >> pci_read_bridge_buses in the generic layer since reading the bridge > >> bases is not related to resources assignment; this implies that it > >> can be carried out safely on PCI_PROBE_ONLY systems too and should > >> not affect architectures (alpha, mips) that check the PCI_PROBE_ONLY > >> flag before reading the bridge bases. > >> > >> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> > >> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> > >> Cc: James E.J. Bottomley <jejb@xxxxxxxxxxxxxxxx> > >> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> > >> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > >> Cc: Richard Henderson <rth@xxxxxxxxxxx> > >> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> > >> Cc: David Howells <dhowells@xxxxxxxxxx> > >> Cc: Russell King <linux@xxxxxxxxxxxxxxxx> > >> Cc: Tony Luck <tony.luck@xxxxxxxxx> > >> Cc: David S. Miller <davem@xxxxxxxxxxxxx> > >> Cc: Ingo Molnar <mingo@xxxxxxxxxx> > >> Cc: Guenter Roeck <linux@xxxxxxxxxxxx> > >> Cc: Michal Simek <monstr@xxxxxxxxx> > >> Cc: Chris Zankel <chris@xxxxxxxxxx> > >> --- > >> v2->v3: > >> > >> - Dropped RFC status > >> - Removed bridge resources claiming from pci_read_bridge_bases() > > > > What do you want me to do with this patch ? I removed the resource > > claiming - ie the only controversial bit, I can only test on > > arm64, I would like to make some progress on this otherwise > > I will have to add the bridge bases read to arm64 pcibios_fixup_bus() > > and be done with this. > > > > Lorenzo, > > please give me a few days to test it. I was out on vacation for > the last two weeks, and I am still struggling to get my test systems > back to a working state. No worries, I just wanted to make sure we can make progress on this, I do not think there is anything controversial in this set, it just requires testing the mechanical change on all affected archs, that's the problem. Thanks a lot for your help ! Lorenzo -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
