Re: [PATCH 06/19] csky: IRQ handling

From: Guo Ren
Date: Mon Mar 19 2018 - 22:07:15 EST


Hi Thomas,

On Mon, Mar 19, 2018 at 02:16:37PM +0100, Thomas Gleixner wrote:
> > +static inline unsigned long arch_local_irq_save(void)
> > +{
> > + unsigned long flags;
>
> Newline between declaration and code please.
OK

> > +void csky_do_IRQ(int irq, struct pt_regs *regs)
>
> static? If not, then it needs a declaration in a header somewhere.
Yes, need static.

> > +asmlinkage void csky_do_auto_IRQ(struct pt_regs *regs)
> > +{
> > + unsigned long irq, psr;
> > +
> > + asm volatile("mfcr %0, psr":"=r"(psr));
> > +
> > + irq = (psr >> 16) & 0xff;
> > +
> > + if (irq == 10)
> > + irq = csky_get_auto_irqno();
> > + else
> > + irq -= 32;
>
> Please add a comment explaining this magic here. Magic numbers w/o
> explanation are bad.
Yes, you are right. I will fixup them next.

PSR is our Processor Status Register and it store the vector number.

'10' is our auto-interrupt exception entry and we need get the irqno
from the interrupt-controller.

The "vector num > 32" is our vector interrupt exception entries, so we
can calculate the irq-num by vector-num and no need to access the
interrupt-controller's io regs.

Best Regards
Guo Ren