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

[Shannon Zhao]

On 2015/4/14 17:59, Michael S. Tsirkin wrote:
> 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.
> 

Ok, will add.

-- 
Thanks,
Shannon