Re: [PATCH 2/2] of/irq: do irq resolution in platform_get_irq

[Grant Likely <grant.likely@linaro.org>]

On Wed, 23 Apr 2014 16:42:13 -0700, Tony Lindgren <tony@atomide.com> wrote:
> * Rob Herring <robherring2@gmail.com> [140423 15:58]:
> > From: Rob Herring <robh@kernel.org>
> > 
> > Currently we get the following kind of errors if we try to use interrupt
> > phandles to irqchips that have not yet initialized:
> > 
> > irq: no irq domain found for /ocp/pinmux@48002030 !
> > ------------[ cut here ]------------
> > WARNING: CPU: 0 PID: 1 at drivers/of/platform.c:171 of_device_alloc+0x144/0x184()
> > Modules linked in:
> > CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.12.0-00038-g42a9708 #1012
> > (show_stack+0x14/0x1c)
> > (dump_stack+0x6c/0xa0)
> > (warn_slowpath_common+0x64/0x84)
> > (warn_slowpath_null+0x1c/0x24)
> > (of_device_alloc+0x144/0x184)
> > (of_platform_device_create_pdata+0x44/0x9c)
> > (of_platform_bus_create+0xd0/0x170)
> > (of_platform_bus_create+0x12c/0x170)
> > (of_platform_populate+0x60/0x98)
> > 
> > This is because we're wrongly trying to populate resources that are not
> > yet available. It's perfectly valid to create irqchips dynamically, so
> > let's fix up the issue by resolving the interrupt resources when
> > platform_get_irq is called.
> > 
> > And then we also need to accept the fact that some irqdomains do not
> > exist that early on, and only get initialized later on. So we can
> > make the current WARN_ON into just into a pr_debug().
> > 
> > We still attempt to populate irq resources when we create the devices.
> > This allows current drivers which don't use platform_get_irq to continue
> > to function. Once all drivers are fixed, this code can be removed.
> > 
> > Suggested-by: Russell King <linux@arm.linux.org.uk>
> > Signed-off-by: Rob Herring <robh@kernel.org>
> > Signed-off-by: Tony Lindgren <tony@atomide.com>
> 
> Great, works for me. Hopefully this patch is non-intrusive enough for
> people for the -rc cycle too?

Both patches look good. I've put them in my tree and will push it out
shortly. I want to make sure there are no regressions on PowerPC, so
I'll give it a few days in linux-next before asking Linus to pull.

Tony, how far back does this need to be backported?

g.