Re: Design doc of adding ACPI support for arm64 on Xen - version 2

[Julien Grall <julien.grall@citrix.com>]

Hi Shannon,

On 07/08/15 03:11, Shannon Zhao wrote:
> 2. Create minimal DT to pass required information to Dom0
> ----------------------------------------------------------
> The minimal DT mainly passes Dom0 bootargs, address and size of initrd
> (if available), address and size of uefi system table, address and size
> of uefi memory table, uefi-mmap-desc-size and uefi-mmap-desc-ver.
> 
> An example of the minimal DT:
> / {
>     #address-cells = <2>;
>     #size-cells = <1>;
>     chosen {
>         bootargs = "kernel=Image console=hvc0 earlycon=pl011,0x1c090000
> root=/dev/vda2 rw rootfstype=ext4 init=/bin/sh acpi=force";
>         linux,initrd-start = <0xXXXXXXXX>;
>         linux,initrd-end = <0xXXXXXXXX>;
>         linux,uefi-system-table = <0xXXXXXXXX>;
>         linux,uefi-mmap-start = <0xXXXXXXXX>;
>         linux,uefi-mmap-size = <0xXXXXXXXX>;
>         linux,uefi-mmap-desc-size = <0xXXXXXXXX>;
>         linux,uefi-mmap-desc-ver = <0xXXXXXXXX>;
>     };
> };
> 
> For details loook at
> https://github.com/torvalds/linux/blob/master/Documentation/arm/uefi.txt

AFAICT, the device tree properties in this documentation are only used
in order to communicate between the UEFI stub and Linux.

This means that those properties are not standardize and can change at
any time by Linux folks. They don't even live in Documentation/devicetree/

I would also expect to see the same needs for FreeBSD running as DOM0
with ACPI.

So it looks like to me that a generic name would be better for all those
properties.

Regards,

-- 
Julien Grall