On 2022-06-29 14:41, Pavel Machek wrote:
Hi!
> >> +#define PLIC_QUIRK_EDGE_INTERRUPT BIT(0)
> >>
> >> struct plic_priv {
> >> struct cpumask lmask;
> >> struct irq_domain *irqdomain;
> >> void __iomem *regs;
> >> + u32 plic_quirks;
> >> };
> >>
> >> What about something like above?
> >
> > LGTM.
> >
> > Marc suggested to make this unsigned long, but TBH, that won't make
> > much of a difference. PLICs are present on RV32 SoCs, too, so you
> > cannot rely on having more than 32 bits anyway.
>
> But it will make a difference on a 64bit platform, as we want to
> use test_bit() and co to check for features.
>
Ok will change that to unsigned long and use the test_bit/set_bit
instead.
Is there good enough reason for that? test_bit/... are when you need
atomicity, and that's not the case here. Plain old & ... should be
enough.
On any save architecture, '&' and test_bit() are the same thing.
Only RMW operations require atomicity.
'unsigned long' is is.
M.
--
Jazz is not dead. It just smells funny...
