GICv2: Add driver API to set PE target mask

The PE target mask is used to translate linear PE index (returned by
platform core position) to a bit mask used when targeting interrupts to
a PE, viz. when raising SGIs and routing SPIs.

The platform shall:

  - Populate the driver data with a pointer to array that's to contain
    per-PE target masks.

  - Invoke the new driver API 'gicv2_set_pe_target_mask()' during
    per-CPU initialization so that the driver populates the target mask
    for that CPU.

Platforms that don't intend to target interrupts or raise SGIs need not
populate this.

Change-Id: Ic0db54da86915e9dccd82fff51479bc3c1fdc968
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/drivers/arm/gic/v2/gicv2_main.c b/drivers/arm/gic/v2/gicv2_main.c
index 7759a551..28266807 100644
--- a/drivers/arm/gic/v2/gicv2_main.c
+++ b/drivers/arm/gic/v2/gicv2_main.c
@@ -252,3 +252,26 @@ unsigned int gicv2_get_running_priority(void)
 
 	return gicc_read_rpr(driver_data->gicc_base);
 }
+
+/*******************************************************************************
+ * This function sets the GICv2 target mask pattern for the current PE. The PE
+ * target mask is used to translate linear PE index (returned by platform core
+ * position) to a bit mask used when targeting interrupts to a PE, viz. when
+ * raising SGIs and routing SPIs.
+ ******************************************************************************/
+void gicv2_set_pe_target_mask(unsigned int proc_num)
+{
+	assert(driver_data);
+	assert(driver_data->gicd_base);
+	assert(driver_data->target_masks);
+	assert(proc_num < GICV2_MAX_TARGET_PE);
+	assert(proc_num < driver_data->target_masks_num);
+
+	/* Return if the target mask is already populated */
+	if (driver_data->target_masks[proc_num])
+		return;
+
+	/* Read target register corresponding to this CPU */
+	driver_data->target_masks[proc_num] =
+		gicv2_get_cpuif_id(driver_data->gicd_base);
+}