Re: [PATCH] docs: fusa: Add dom0less domain configuration requirements

[Julien Grall <julien@xxxxxxx>]

Hi Ayan,

On 15/11/2024 18:53, Ayan Kumar Halder wrote:
> > > +Assign vCPUs from CPU pool
> > > +--------------------------
> > > +
> > > +`XenSwdgn~arm64_assign_vcpus_cpu_pool~1`
> > > +
> > > +Description:
> > > +Xen shall assign vCPUs to a domain from a CPU pool.
> > Same remark about the wording. You create a domain with N vCPUs and 
> > *assign* a CPU pool to a domain. 
> Ok, so all the previous 3 requirements can be merged into
>
> Xen shall create a domain with N vCPUs and assign a CPU pool to a domain.
>
> Or
>
> Xen shall create a domain with N vCPUs.
I think this one is better because it is not mandatory for the user to 
select a CPU pool and you will have it ...
> (which of the two looks better to you if we keep the next requirement ?)
... by the next one.

> Comments:
>
> Here N is determined by the device tree configuration provided by the user.
>
> > You also assign pCPU to a CPU pool.
> >
> > But I am not sure about if this requirement is actually necessary 
> > given ...
> > > +
> > > +Rationale:
> > > +
> > > +Comments:
> > > +
> > > +Covers:
> > > + - `XenProd~static_domains_configuration~1`
> > > +
> > > +Specify CPU pool scheduler
> > > +--------------------------
> > > +
> > > +`XenSwdgn~arm64_specify_cpu_pool_scheduler~1`
> > > +
> > > +Description:
> > > +Xen shall assign a CPU pool scheduler to a domain.
> > ... you have th is one.
> So, we can keep it as it is.
> > > +
> > > +Rationale:
> > > +
> > > +Comments:
> > > +
> > > +Covers:
> > > + - `XenProd~static_domains_configuration~1`
> > > +
> > > +Assign virtual UART
> > > +-------------------
> > > +
> > > +`XenSwdgn~arm64_assign_virtual_uart~1`
> > > +
> > > +Description:
> > > +Xen shall assign a virtual UART to a domain.
> > Are we talking about the virtual PL011 or the fake emulation of the 
> > real UART we do?
> virtual PL011.
Is it possible to specify it in the market requirements?

[...]

> > > +
> > > +Static VM definition
> > > +--------------------
> > > +
> > > +`XenMkt~static_vm_definition~1`
> > > +
> > > +Description:
> > > +Xen shall support specifying resources for a domain.
> > Compare to the other requirements, this is quite a vague. Should we 
> > list the resources?
> The list of resources depends on what the user has provided in the 
> device tree configuration.
> But the requirement is correct as it is. Xen allows direct assignment of 
> devices to domains (ie passthrough).
> How do you want to write it ?
This is probably a better question for Bertrand. I don't know how market 
requirements are usually described. I was making a comparison with the 
other where you explicitely listed the expected resources (e.g. CPU, 
Memory, device).
Cheers,

--
Julien Grall