Re: [PATCH] ata: Don't use NO_IRQ in pata_of_platform driver

Russell King - ARM Linux
2011-12-06T20:01:34Z

On Tue, Dec 06, 2011 at 11:20:49AM -0800, Linus Torvalds wrote:
> Not for any device driver, though.
>
> It's used entirely internally, and it doesn't even use
> "request_irq()". It uses the magic internal "setup_irq()" and never
> *ever* exposes irq0 as anything that a driver can see.
>
> That's what matters. You can use irq0 in ARM land all you like, AS
> LONG AS IT'S SOME HIDDEN INTERNAL USE. No drivers. No *nothing* that
> ever uses that absolutely *idiotic* NO_IRQ crap.
>
> In fact, you may be *forced* to use what is "physically" irq0 - it's
> just that you should never expose it as such to drivers. And x86
> doesn't.
>
> So Russell, if you think this has anything to do with NO_IRQ, and how
> x86 isn't doing things right, you're wrong. It's just like the
> internal exception thing, or the magical "cascade interrupt", or the
> "x87 exception mapped through the PIC". They are magic hidden
> interrupts that are set up in one place (well, one place *each*), and
> are never exposed anywhere else.
>
> The problem with NO_IRQ is that stupid "we expose our mind-numbingly
> stupid interfaces across the whole kernel".
>
> x86 never did that. ARM still does. x86 doesn't have to fix anything. ARM does.

Remember you said that I shouldn't take things personally? Well,
this is one issue I really don't care about. I don't think any
platform I _actually_ have will be impacted by any change in this
area. Other platform maintainers may have their own issues but
that's not _my_ problem.