Hi Julien,
On 05/10/2023 18:54, Julien Grall wrote:
>
>
> From: Julien Grall <jgr...@amazon.com>
>
> Per ACPI 6.5 section 5.2.25 ("Generic Timer Description Table (GTDT)"),
> the fields "Secure EL1 Timer GSIV/Flags" are optional and an OS running
> in non-secure world is meant to ignore the values.
>
> However, Xen is trying to reserve the value. When booting on Graviton
> 2 metal instances, this would result to crash a boot because the
> value is 0 which is already reserved (I haven't checked for which device).
Per my understanding it is not reserved by any device.
0 means SGI and for SGIs we pre-reserve the bits in allocated_irqs at the very
start.
~Michal
