Re: [Xen-devel] [for-4.7 2/2] xen/arm: Document the behavior of XENMAPSPACE_dev_mmio

[Julien Grall <julien.grall@xxxxxxx>]

Hi Jan,

On 25/05/16 14:14, Jan Beulich wrote:
> > > > On 25.05.16 at 13:41, <julien.grall@xxxxxxx> wrote:
> > --- a/xen/include/public/memory.h
> > +++ b/xen/include/public/memory.h
> > @@ -220,7 +220,10 @@ DEFINE_XEN_GUEST_HANDLE(xen_machphys_mapping_t);
> >   #define XENMAPSPACE_gmfn_range   3 /* GMFN range, XENMEM_add_to_physmap only. 
> > */
> >   #define XENMAPSPACE_gmfn_foreign 4 /* GMFN from another dom,
> >                                       * XENMEM_add_to_physmap_batch only. */
> > -#define XENMAPSPACE_dev_mmio     5 /* device mmio region */
> > +#define XENMAPSPACE_dev_mmio     5 /* device mmio region
> > +                                      On ARM, the region will be mapped
> > +                                      in stage-2 using the memory attribute
> > +                                      Device_nGnRE. */
> Since this is unimplemented on x86, may I suggest to make this "ARM
> only; the region will be ..."?
Sounds good.

> Also - is Device_nGnRE a term uniform between ARM32 and ARM64?
Actually it should be Device-nGnRE to match with the spec. This has been 
introduced on Armv8. Previously for Armv7, the name was "Device", 
although the behavior is exactly the same.
I could say:

"ARM only; the region will be mapped in Stage-2 using the memory 
attribute 'Device-nGnRE' (previously named 'Device' on ARMv7)".
Regards,

--
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel