On Fri, Jun 10, 2016 at 04:14:58PM +0100, Lorenzo Pieralisi wrote:

Hi Bjorn, Tomasz,

On Tue, Jun 07, 2016 at 07:15:59PM -0500, Bjorn Helgaas wrote:

[...]

quoted

quoted

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index eb431b5..2b52178 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c

@@ -7,6 +7,7 @@
  *	Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
  */
 
+#include <linux/acpi.h>
 #include <linux/kernel.h>
 #include <linux/delay.h>
 #include <linux/init.h>

@@ -4941,7 +4942,7 @@ int pci_get_new_domain_nr(void)
 }
 
 #ifdef CONFIG_PCI_DOMAINS_GENERIC
-void pci_bus_assign_domain_nr(struct pci_bus *bus, struct device *parent)
+static int of_pci_bus_domain_nr(struct device *parent)

Can we do a little cleanup before this patch?  

  - pci_bus_assign_domain_nr() is only used inside drivers/pci, so
    maybe we move the prototype to drivers/pci/pci.h?

  - I don't really like the style of calling a function that
    internally assigns bus->domain_nr.  Could we do something like
    this instead?

    int pci_bus_domain_nr(...)
    {
      ...
      return domain;
    }

    ... pci_create_root_bus(...)
    {
      ...
      b->domain_nr = pci_bus_domain_nr(...);

We noticed while preparing v9, that this would force us to
write an empty pci_bus_domain_nr() prototype for
!PCI_DOMAINS_GENERIC (ie every arch but ARM/ARM64) that should
return 0 to keep current behaviour unchanged.

That's why pci_bus_assign_domain_nr() was there, so that it
was compiled out on !PCI_DOMAINS_GENERIC.

I really would like v9 to be final so let's fix it before posting it
shortly please.

For the above we have three options:

1) Leave code as-is in v8

2) in pci_create_root_bus():
#ifdef CONFIG_PCI_DOMAINS_GENERIC
       b->domain_nr = pci_bus_domain_nr(...);
#endif

+ other changes requested above

3) in pci_create_root_bus()

b->domain_nr = pci_bus_domain_nr(...);

unguarded and a stub:

#ifndef CONFIG_PCI_DOMAINS_GENERIC
static inline int pci_bus_domain_nr() { return 0; }
#endif

+ other changes requested above

Actually, Tomasz made me notice that pci_bus.domain_nr is
only declared for CONFIG_PCI_DOMAINS_GENERIC so (3) is not
even an option and IMO (2) is not much nicer than code in
v8 as-is with an ifdef in the middle of pci_create_root_bus().

Thanks,
Lorenzo