[PATCH-WIP 01/13] xen/arm: use r12 to pass the hypercall number to the hypervisor

[Stefano Stabellini]

On Tue, 28 Feb 2012, Dave Martin wrote:
> > Given that Stefano is proposing to make the ISS a (per-hypervisor)
> > constant we could consider just defining the Thumb and non-Thumb
> > constants instead of doing all the construction with the __HVC_IMM stuff
> > -- that would remove a big bit of the macroization.
> 
> It's not quite as simple as that -- emitting instructions using data
> directives is not endianness safe, and even in the cases where .long gives
> the right result for ARM, it gives the wrong result for 32-bit Thumb
> instructions if the opcode is given in human-readable order.
> 
> I was trying to solve the same problem for the kvm guys with some global
> macros -- I'm aiming to get a patch posted soon, so I'll make sure
> you're on CC.
 
That would be great, thanks!