Re: [RFC PATCH 0/3] ACPI: ARM AMBA bus connector resource

[Hanjun Guo <hanjun.guo@linaro.org>]

On 2013-10-23 8:13, Anderson, Brandon wrote:
> Is the proposed ASL format appropriate? I recognize that the ASL

It is ok for me. it represents the device topology very clear also.

> definitions for these devices must be standardized across all ARM ACPI
> platform definitions if we want the software to work consistently,
> so this is an important aspect to agree upon.
> 
> How about contrasting it with an alternative where each device has _HID
> of "AMBA0000" and there's no top-level 'Device (AMBA)'? This would mean
> that all the devices would be labeled by ACPI subsystem as "AMBA0000:NN" 
> instead of "device:NN". However, with this solution there would be no easy
> way to define a default clock. See example below.

I think a top-level 'Device (AMBA)' is needed. there is a good example
for PCI host bridge, its HID is PNP0A08 or PNP0A03, and there are a top level
device for PCI host bridge and child devices with different HIDs.

if there's no top-level 'Device (AMBA)', AMBA0000:NN will confuse people if
there are multi AMBAs in the system, people will think that AMBA0000:01 is
the second AMBA bus in the system but not some devices under AMBA bus.

Thanks
Hanjun