Re: [Qemu-arm] [Qemu-devel] [RFC 0/2] ARM virt: Support up to 256 PCIe buses

[Peter Maydell]

On 23 May 2018 at 21:52, Laszlo Ersek <address@hidden> wrote:
> On 05/23/18 22:40, Auger Eric wrote:
>> On 05/23/2018 07:45 PM, Laszlo Ersek wrote:
>
>>> Regarding the second patch, I do believe we need "more sophistication"
>>> there. For example, I guess it could be possible to distinguish "-cpu
>>> cortex-a15" from "-cpu cortex-a57" somehow, and stick with the low/small
>>> ECAM in the former case. (The 32-bit firmware already runs on cortex-a15
>>> only, and not on cortex-a57, according to my testing.)
>>
>> So we should detect we are in ACPI boot  + aarch32 mode to force legacy
>> ECAM region, right?
>
> Agree about the aarch32 subcondition.
>
> However, "ACPI vs. DT" is not the right "other" subcondition here;
> instead we should (minimally) check "firmware vs. no firmware". See the
> "firmware_loaded" boolean field.

Won't it also break a guest which is just Linux loaded not via
firmware which is an aarch32 kernel without LPAE support?

thanks
-- PMM