Re: [PATCH 1/3] Add a new member name to structure irq_host

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

On Tue, 2007-07-24 at 09:22 +1000, Michael Ellerman wrote:
> On Tue, 2007-07-24 at 08:04 +1000, Benjamin Herrenschmidt wrote:
> > On Mon, 2007-07-23 at 19:13 +0800, Chen Gong wrote:
> > > This patch adds a new member 'name' for irq host's name to
> > > structure irq_host and modifies the definition of the
> > > function irq_alloc_host(). The assignment to the
> > > irq host's name is also added to irq_alloc_host().
> > 
> > I would instead prefer adding a irq_name callback to host, which would
> > return a per-irq name. In some cases, they could return the OF path to
> > the host for example.
> 
> The pity is, for the 75% [1] of irq_hosts that have a device_node, they
> will all have to implement the name callback, because they all store the
> of node differently.
> 
> Which makes me think (again) that we should have an optional device_node
> pointer in irq_host. I know you said you wanted the irq stuff to be OF
> agnostic, but the reality is most of the implementations do have an OF
> node. And all of the newer irq_host implementations do, with the
> exception of PS3 and celleb - which are special.

Won't work well in practice due to things like:

 - Cell iic -> one node per core, but one global host
 - xics -> one node per source controller (lots of them in the tree) but
one global host

Ben.