Re: [Qemu-devel] [PATCH v4 19/20] hw/arm/virt-acpi-build: Add PCIe controller in ACPI DSDT table

[Michael S. Tsirkin]

On Tue, Apr 14, 2015 at 05:55:39PM +0800, Shannon Zhao wrote:
> On 2015/4/14 17:30, Peter Maydell wrote:
> > On 14 April 2015 at 02:10, Shannon Zhao <address@hidden> wrote:
> >> On 2015/4/13 23:58, Alex Bennée wrote:
> >>>
> >>> Shannon Zhao <address@hidden> writes:
> >>>> +    UUID = aml_touuid(0x33DB4D5B, 0x1FF7, 0x401C, 0x9657,
> >>>> 0x7441C03DD766);
> >>>
> >>> This looks like a fairly unreadable uuid already. What are these magic 
> >>> numbers?
> >>>
> >>
> >> Yes, this will be modified to use string according to the spec. Like below 
> >> way:
> >>
> >> UUID = aml_touuid("33DB4D5B-1FF7-401C-9657-7441C03DD766");
> > 
> > Those are still magic numbers, you've  just put them into
> > a different format. Where do they come from? What do they mean?
> > 
> 
> This is from the PCI Firmware Spec.
> 
> "The _OSC interface for a PCI/PCI-X/PCI Express hierarchy is identified by 
> the Universal Unique
> IDentifier (UUID) 33db4d5b-1ff7-401c-9657-7441c03dd766."
> 
> "The UUID in _DSM in this context is {E5C937D0-3553-4d7a-9117-EA4D19C3434D}"
> 
> Maybe I should use a macro definition for them.

If there's a single instance of use, a comment would
do as well.

> -- 
> Thanks,
> Shannon