Benjamin Herrenschmidt wrote:
> On Sun, 2009-11-22 at 23:01 +0100, Albert Herranz wrote:
>
>> +static void flipper_pic_mask_and_ack(unsigned int virq)
>> +{
>> + int irq = virq_to_hw(virq);
>> + void __iomem *io_base = get_irq_chip_data(virq);
>> +
>> + clear_bit(irq, io_base + FLIPPER_IMR);
>> + set_bit(irq, io_base + FLIPPER_ICR);
>> +}
>
> Do not use clear_bit and set_bit on IOs. They will do lwarx/stwcx. which
> is really not what you want. You can use __clear_bit and __set_bit but
> it's still fishy. Those operate on unsigned long, so the size vary
> between 32 and 64 bit etc... not something you care that much about, but
> it's still the wrong tool for the job.
>
> Do those guys have more than 32 interrupts ? If not, just hand
> code the msak & shifts. If they do, then maybe stick with __clear_bit()
> and __set_bit() which are the non atomic variants.
>
There can be only 32 interrupt sources per pic.
I'll build a mask and check if just a simple write works too (it should IMHO),
instead of a RWM.
> Cheers,
> Ben.
>
Thanks,
Albert
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
