Tony, The last patch I posted didn't work quite right. It seems we do actually come into this macro with none of the pending bits set. Presumably, because the interrupt hasn't been ack'd yet. Anyway, I've tested this patch and I think it's golden. It ack's spurious interrupts and lets the user know that one has occured by setting irq to NR_IRQS then arch/arm/kernel/irq.c will use bad_irq_desc when it processes the interrupt. This message get's printed upon spurious interrupt: ->handle_irq(): c0073448, handle_bad_irq+0x0/0x228 ->chip(): 00000000, 0x0 ->action(): 00000000 The only bad thing is that it doesn't notify the user WHICH spurious interrupt happened. Any ideas on solving that? Rick --- linux-omap-2.6/arch/arm/plat-omap/include/mach/entry-macro.S.git 2008-10-22 20:01:33.000000000 -0700 +++ linux-omap-2.6/arch/arm/plat-omap/include/mach/entry-macro.S 2008-10-27 08:41:08.000000000 -0700 @@ -66,7 +66,11 @@ #endif #define INTCPS_SIR_IRQ_OFFSET 0x0040 /* Active interrupt offset */ -#define ACTIVEIRQ_MASK 0x7f /* Active interrupt bits */ +#define INTCPS_CONTROL 0x0048 /* new interrupt agreement bits */ +#define INTCPS_PENDING_IRQ_1 0x0098 /* IRQ pending reg 1 */ +#define INTCPS_PENDING_IRQ_2 0x00b8 /* IRQ pending reg 2 */ +#define INTCPS_PENDING_IRQ_3 0x00d8 /* IRQ pending reg 3 */ +#define INTCPS_CONTROL_NEWIRQAGR 0x0001 /* Reset IRQ output and enable new IRQ generation */ .macro disable_fiq .endm @@ -79,18 +83,19 @@ .macro get_irqnr_and_base, irqnr, irqstat, base, tmp ldr \base, =OMAP2_VA_IC_BASE - ldr \irqnr, [\base, #0x98] /* IRQ pending reg 1 */ - cmp \irqnr, #0x0 - bne 2222f - ldr \irqnr, [\base, #0xb8] /* IRQ pending reg 2 */ - cmp \irqnr, #0x0 - bne 2222f - ldr \irqnr, [\base, #0xd8] /* IRQ pending reg 3 */ - cmp \irqnr, #0x0 + ldr \irqstat, [\base, #INTCPS_PENDING_IRQ_1] /* IRQ pending reg 1 */ + ldr \tmp, [\base, #INTCPS_PENDING_IRQ_2] /* IRQ pending reg 2 */ + orr \irqstat, \irqstat, \tmp /* or them all together */ + ldr \tmp, [\base, #INTCPS_PENDING_IRQ_3] /* IRQ pending reg 3 */ + orrs \irqstat, \irqstat, \tmp /* set condition code Z if interrupt */ + beq 2222f /* if there are no interrupt bits set, leave with Z=1 */ + ldr \irqnr, [\base, #INTCPS_SIR_IRQ_OFFSET] + adds \tmp, \irqnr, #1 /* change from zero based to 1 based so we clear Z */ + bpl 2222f /* if no spurious interrupt */ + mov \tmp, #INTCPS_CONTROL_NEWIRQAGR /* Ack the spurious irq */ + str \tmp, [\base, #INTCPS_CONTROL] + movw \irqnr, #NR_IRQS /* set to NR_IRQS so that bad_irq_desc() get's called */ 2222: - ldrne \irqnr, [\base, #INTCPS_SIR_IRQ_OFFSET] - and \irqnr, \irqnr, #ACTIVEIRQ_MASK /* Clear spurious bits */ - .endm .macro irq_prio_table -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html