[PATCH 01/28] PCI: Rip out pci_bus_add_devices() from pci_scan_bus()

Yinghai Lu yinghai at kernel.org
Fri Jan 16 15:16:28 PST 2015


On Fri, Jan 16, 2015 at 3:15 PM, Yinghai Lu <yinghai at kernel.org> wrote:
> On Thu, Jan 15, 2015 at 5:43 PM, Yijing Wang <wangyijing at huawei.com> wrote:
>> Pci_bus_add_devices() should not be placed in pci_scan_bus().
>> Now pci device will be added to driver core once its
>> creation. All things left in pci_bus_add_devices() are
>> driver attachment and other trivial sysfs things.
>> Pci_scan_bus() should be the function responsible for
>> scanning PCI devices, not including driver attachment.
>> Other, some callers(m68k,unicore32,alpha) of pci_scan_bus()
>> will call pci_bus_size_bridges() and pci_bus_assign_resources()
>> after pci_scan_bus().
>>
>> E.g.
>> In m68k
>> mcf_pci_init()
>>         pci_scan_bus()
>>                 ...
>>                 pci_bus_add_devices() --- try to attach driver
>>         pci_fixup_irqs()
>>         pci_bus_size_bridges()
>>         pci_bus_assign_resources()
>>
>> It is not correct, resources should be assigned correctly
>> before attaching driver.
>
No, for booting path, at that time pci drivers are *NOT* loaded yet.

Thanks

Yinghai



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