Re: ARM: OMAP3: Fix get_irqnr_and_base to clear spurious interrupt bits

[Rick Bronson <rick@efn.org>]

  Sorry if I'm late in the game for changes to entry-macro.S but I
worked on this code a bit ago and have been testing it.  What I have,
I think, is a little more straight forward.  Note that it doesn't have
the added mask for the spurious bits, but it does check for
spurious interrupts and handles them.

  Rick



--- linux-omap-2.6/arch/arm/plat-omap/include/mach/entry-macro.S.~1~	2008-10-16 13:33:31.000000000 -0700
+++ linux-omap-2.6/arch/arm/plat-omap/include/mach/entry-macro.S	2008-10-17 11:38:18.000000000 -0700
@@ -65,7 +65,11 @@
 #include <mach/omap34xx.h>
 #endif
 
-#define INTCPS_SIR_IRQ_OFFSET	0x0040		/* Active interrupt number */
+#define INTCPS_SIR_IRQ_OFFSET	0x0040	/* Active interrupt number */
+#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 */
 
 		.macro	disable_fiq
 		.endm
@@ -78,17 +82,19 @@
 
 		.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
-2222:
-		ldrne	\irqnr, [\base, #INTCPS_SIR_IRQ_OFFSET]
-
+		ldr	\irqnr, [\base, #INTCPS_SIR_IRQ_OFFSET]
+		cmp	\irqnr, #0  /* check for negative */
+		movmi	\tmp, #0x1 /* Ack the spurious irq, this lets it
+					* generate a bad irq error message,
+					* but prevents infinitely repeating
+					* irq.
+					*/
+		strmi	\tmp, [\base, #INTCPS_CONTROL]
+		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 */
 		.endm
 
 		.macro	irq_prio_table