GIC: Add API to set/clear interrupt pending

API documentation updated.

Change-Id: I14e33cfc7dfa93257c82d76fae186b17a1b6d266
Co-authored-by: Yousuf A <yousuf.sait@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
diff --git a/drivers/arm/gic/v3/gicv3_main.c b/drivers/arm/gic/v3/gicv3_main.c
index c81ba95..43dd77f 100644
--- a/drivers/arm/gic/v3/gicv3_main.c
+++ b/drivers/arm/gic/v3/gicv3_main.c
@@ -1037,3 +1037,55 @@
 		}
 	}
 }
+
+/*******************************************************************************
+ * This function clears the pending status of an interrupt identified by id.
+ * The proc_num is used if the interrupt is SGI or PPI, and programs the
+ * corresponding Redistributor interface.
+ ******************************************************************************/
+void gicv3_clear_interrupt_pending(unsigned int id, unsigned int proc_num)
+{
+	assert(gicv3_driver_data);
+	assert(gicv3_driver_data->gicd_base);
+	assert(proc_num < gicv3_driver_data->rdistif_num);
+	assert(gicv3_driver_data->rdistif_base_addrs);
+
+	/*
+	 * Clear pending interrupt, and ensure that any shared variable updates
+	 * depending on out of band interrupt trigger are observed afterwards.
+	 */
+	if (id < MIN_SPI_ID) {
+		/* For SGIs and PPIs */
+		gicr_set_icpendr0(gicv3_driver_data->rdistif_base_addrs[proc_num],
+				id);
+	} else {
+		gicd_set_icpendr(gicv3_driver_data->gicd_base, id);
+	}
+	dsbishst();
+}
+
+/*******************************************************************************
+ * This function sets the pending status of an interrupt identified by id.
+ * The proc_num is used if the interrupt is SGI or PPI and programs the
+ * corresponding Redistributor interface.
+ ******************************************************************************/
+void gicv3_set_interrupt_pending(unsigned int id, unsigned int proc_num)
+{
+	assert(gicv3_driver_data);
+	assert(gicv3_driver_data->gicd_base);
+	assert(proc_num < gicv3_driver_data->rdistif_num);
+	assert(gicv3_driver_data->rdistif_base_addrs);
+
+	/*
+	 * Ensure that any shared variable updates depending on out of band
+	 * interrupt trigger are observed before setting interrupt pending.
+	 */
+	dsbishst();
+	if (id < MIN_SPI_ID) {
+		/* For SGIs and PPIs */
+		gicr_set_ispendr0(gicv3_driver_data->rdistif_base_addrs[proc_num],
+				id);
+	} else {
+		gicd_set_ispendr(gicv3_driver_data->gicd_base, id);
+	}
+}