Add a flag field to struct gic_irqsrc and use it to mark when we should

write to the End of Interrupt (EOI) register before handling the interrupt.
This should be a noop as it will be set for all edge triggered interrupts,
however this will not be the case for MSI interrupts. These are also edge
triggered, however we should not write to the EOI register until later in
arm_gic_pre_ithread.

Obtained from:	ABT Systems Ltd
Sponsored by:	The FreeBSD Foundation

1 files changed, 8 insertions, 3 deletions

diff --git a/sys/arm/arm/gic.c b/sys/arm/arm/gic.c
index ced66d5..0d201fd 100644
--- a/sys/arm/arm/gic.c
+++ b/sys/arm/arm/gic.c
@@ -122,6 +122,8 @@ struct gic_irqsrc {
 	uint32_t		gi_irq;
 	enum intr_polarity	gi_pol;
 	enum intr_trigger	gi_trig;
+#define GI_FLAG_EARLY_EOI	(1 << 0)
+	u_int			gi_flags;
 };
 
 static u_int gic_irq_cpu;
@@ -853,12 +855,12 @@ dispatch_irq:
 #ifdef GIC_DEBUG_SPURIOUS
 	sc->last_irq[PCPU_GET(cpuid)] = irq;
 #endif
-	if (gi->gi_trig == INTR_TRIGGER_EDGE)
+	if ((gi->gi_flags & GI_FLAG_EARLY_EOI) == GI_FLAG_EARLY_EOI)
 		gic_c_write_4(sc, GICC_EOIR, irq_active_reg);
 
 	if (intr_isrc_dispatch(&gi->gi_isrc, tf) != 0) {
 		gic_irq_mask(sc, irq);
-		if (gi->gi_trig != INTR_TRIGGER_EDGE)
+		if ((gi->gi_flags & GI_FLAG_EARLY_EOI) != GI_FLAG_EARLY_EOI)
 			gic_c_write_4(sc, GICC_EOIR, irq_active_reg);
 		device_printf(sc->gic_dev, "Stray irq %u disabled\n", irq);
 	}
@@ -1087,6 +1089,9 @@ arm_gic_setup_intr(device_t dev, struct intr_irqsrc *isrc,
 
 	gi->gi_pol = pol;
 	gi->gi_trig = trig;
+	/* Edge triggered interrupts need an early EOI sent */
+	if (gi->gi_pol == INTR_TRIGGER_EDGE)
+		gi->gi_flags |= GI_FLAG_EARLY_EOI;
 
 	/*
 	 * XXX - In case that per CPU interrupt is going to be enabled in time
@@ -1160,7 +1165,7 @@ arm_gic_post_filter(device_t dev, struct intr_irqsrc *isrc)
 	struct gic_irqsrc *gi = (struct gic_irqsrc *)isrc;
 
         /* EOI for edge-triggered done earlier. */
-	if (gi->gi_trig == INTR_TRIGGER_EDGE)
+	if ((gi->gi_flags & GI_FLAG_EARLY_EOI) == GI_FLAG_EARLY_EOI)
 		return;
 
 	arm_irq_memory_barrier(0);