Re: [Qemu-arm] [Qemu-devel] [PATCH v2 2/2] hw/arm: Add Arm Enterprise machine type

[Andrew Jones]

On Wed, Jul 25, 2018 at 02:29:09PM +0200, Ard Biesheuvel wrote:
> To prevent spending a disproportionate amount of time on inventing
> ways to parameterize these 'models', which includes interfaces not
> only between UEFI and QEMU but also between ARM-TF and QEMU (and
> potentially between UEFI and ARM-TF as well), could we please consider

I guess a UEFI <=> ARM-TF interface will also need to work on real
hardware, and therefore need a QEMU model. If whatever that interface
needs can also satisfy the UEFI <=> QEMU and ARM-TF <=> interfaces,
then that's all we need - no need for fw-cfg.

> fixed configurations for the non-discoverable bits? If there is a new

Well, at least one thing must to be fixed, which is

 a) address/register where the address of the DTB will be stored
 b) address of the QEMU interface device, e.g. fw-cfg. fw-cfg or
    whatever can then be used to get the DTB.

And I guess everything the SBSA says should be fixed should be fixed.
Otherwise, what's non-discoverable?

> and improved sbsa model in the future, we could call it sbsa-2.0, no?

Of course the model can be versioned, allowing for any change, but
I don't think model versions were meant to be aliases for peripheral
selections. That's what scripts wrapped around qemu are for.

Thanks,
drew