Latest OpenPic changes

[Geert Uytterhoeven]

	Hi Ben,

After two days of hacking I finally found out what went wrong. Your changes to
the OpenPIC code cause my machine to hang in openpic_enable_irq(). I added a
timeout to the do { ... } while (...) loop:

void openpic_enable_irq(u_int irq)
{
        int timeout = 1000000;
        check_arg_irq(irq);
        openpic_clearfield(&ISU[irq - open_pic_irq_offset].Vector_Priority, OPENPIC_MASK);
        /* make sure mask gets to controller before we return to user */
        do {
                mb(); /* sync is probably useless here */
        } while(openpic_readfield(&OpenPIC->Source[irq].Vector_Priority,
                        OPENPIC_MASK) && --timeout);
        if (!timeout)
            printk("openpic_enable_irq %d timeout status 0x%08x\n", irq, openpic_readfield(&OpenPIC->Source[irq].Vector_Priority,OPENPIC_MASK));
}

and OPENPIC_MASK is still set when the loop times out on enabling
IRQ_8259_CASCADE in chrp_init_IRQ(). How is this possible? There's an eieio()
after each register write and the mb() does sync.

Gr{oetje,eeting}s,
--
Geert Uytterhoeven -- Linux/{m68k~Amiga,PPC~CHRP} -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds


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