[PATCH v2 11/13] ARM: only include mach/irqs.h for !SPARSE_IRQ

[grant.likely@secretlab.ca (Grant Likely)]

On Wed, Jan 25, 2012 at 01:23:00PM -0600, Rob Herring wrote:
> On 01/20/2012 04:48 PM, Nicolas Pitre wrote:
> > On Fri, 20 Jan 2012, Rob Herring wrote:
> > 
> >> On 01/20/2012 03:11 PM, Nicolas Pitre wrote:
> >>> On Fri, 20 Jan 2012, Rob Herring wrote:
> >>>
> >>>> From: Rob Herring <rob.herring@calxeda.com>
> >>>>
> >>>> Make mach/irqs.h optional for SPARSE_IRQ. With this change irqs.h can be
> >>>> removed by converting platforms over to sparse irq.
> >>>>
> >>>> This intentionally breaks platforms that enable SPARSE_IRQ.
> >>>
> >>> I don't get what you mean here.  The above seems contradictory.
> >>>
> >>
> >> You're right. The intro explains things more clearly.
> > 
> > The intro won't be part of the git history, so please make sure 
> > individual commit logs are sensible on their own.
> 
> Updated the commit message to this (w/o the email word wrapping):
> 
> ARM: only include mach/irqs.h for !SPARSE_IRQ
> 
> Make mach/irqs.h optional for SPARSE_IRQ. With this change irqs.h can be
> removed by converting platforms over to sparse irq.
> 
> This may break platforms where SPARSE_IRQ is user selectable and is enabled.
> This is on purpose so that SPARSE_IRQ gets properly supported. SPARSE_IRQ
> should not really be a user visible option.
> 
> Platforms either need to set nr_irqs in their machine desc or all irqchips
> used by a platform need to allocate their irq_descs. There cannot be a
> mixture. Once this is done, the platforms can select SPARSE_IRQ. shmobile
> does the latter, and mmp and pxa do the former.
> 
> >> This breaks platforms (at boot time) that don't select SPARSE_IRQ, but 
> >> let users enable it in their config. I don't understand why sparse irq 
> >> is a user visible config option. We could move HAVE_SPARSE_IRQ down to 
> >> each platform that selects SPARSE_IRQ and prevent enabling, but I 
> >> think allowing it to break is good encouragement for others to fix 
> >> those platforms. I'm open to other ideas.
> > 
> > SPARSE_IRQ shouldn't be a user configurable option.  There is just no 
> > point for a user configuring a kernel to be able to change this.
> 
> I agree, but I'm inclined to leave this alone for now. PPC doesn't ever
> select SPARSE_IRQ, but enables it via many defconfigs. So I think
> changing it may cause some problems.

I think ppc can probably be moved to always enable SPARSE_IRQ since every
ppc machine goes through irq_domain anyway.

g.