[PATCH v2 05/22] ARM: dt: tegra30: iommu: Add "nvidia,memory-client"

[Hiroshi Doyu]

On Mon, 29 Jul 2013 19:47:04 +0200
Stephen Warren <swarren at wwwdotorg.org> wrote:

> On 07/29/2013 05:06 AM, Hiroshi Doyu wrote:
> > Stephen Warren <swarren at wwwdotorg.org> wrote @ Wed, 17 Jul 2013 01:14:33 +0200:
> > 
> >> On 07/05/2013 04:44 AM, Hiroshi Doyu wrote:
> >>> Add "nvidia,memory-client" to identify which swgroup ID a device
> >>> belongs to.
> >>
> >> This property also isn't in the documentation.
> >>
> >> Again, if client devices are required to have this new property, the DT
> >> isn't backwards-compatible; fail:-(
> > 
> > If there's no this property, just falling back to use the system
> > default address space. I think that this won't break the
> > compatibility basically. Only problem may be the inconsistency of
> > setting this property among the HWs in the same group.
> 
> When you say "group" there, what kind of group? I thought that each HW
> module had its own "SWGROUP ID", and hence there are no "HWs in the same
> group"?

A "swgroup" can have multiple HWs. So there are 3 concept here.

swgroup: one client to issue request from MC perspective
HW: swgroup can have multiple HWs(real H/W units)
device driver: Can have multiple swgroups.