[PATCH kernel] powerpc/pci/of: Parse unassigned resources

[Alexey Kardashevskiy]

On 18/06/2019 22:15, Michael Ellerman wrote:
> Alexey Kardashevskiy <aik at ozlabs.ru> writes:
>> The pseries platform uses the PCI_PROBE_DEVTREE method of PCI probing
>> which is basically reading "assigned-addresses" of every PCI device.
>> However if the property is missing or zero sized, then there is
>> no fallback of any kind and the PCI resources remain undiscovered, i.e.
>> pdev->resource[] array is empty.
>>
>> This adds a fallback which parses the "reg" property in pretty much same
>> way except it marks resources as "unset" which later makes Linux assign
>> those resources with proper addresses.
> 
> What happens under PowerVM is the big question.
> 
> ie. if we see such a device under PowerVM and then do our own assignment
> what happens?

I'd be surprised not to see at least one "assigned-addresses" under
powervm, and a single assigned bar will do the old behavior.

I guess I could make it depend on "linux,pci-probe-only" (which I will
need for this to work anyway), if that helps, should I?


-- 
Alexey