ARM: GIC: interface to send a SGI directly
The regular gic_raise_softirq() takes as input a CPU mask which is not
adequate when we need to send an IPI to a CPU which is not represented
in the kernel to GIC mapping. That is the case with the b.L switcher
when GIC migration to the inbound CPU has not yet occurred.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index 09fdf3d5..9031171 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -674,6 +674,20 @@
#ifdef CONFIG_BL_SWITCHER
/*
+ * gic_send_sgi - send a SGI directly to given CPU interface number
+ *
+ * cpu_id: the ID for the destination CPU interface
+ * irq: the IPI number to send a SGI for
+ */
+void gic_send_sgi(unsigned int cpu_id, unsigned int irq)
+{
+ BUG_ON(cpu_id >= NR_GIC_CPU_IF);
+ cpu_id = 1 << cpu_id;
+ /* this always happens on GIC0 */
+ writel_relaxed((cpu_id << 16) | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
+}
+
+/*
* gic_get_cpu_id - get the CPU interface ID for the specified CPU
*
* @cpu: the logical CPU number to get the GIC ID for.