drivers: gicv3: add distributor safe configuration

In case of multiple OSes running on different CPU Cores which share the
same GIC controller, need to avoid the distributor re-configured to avoid
crash the OS has already been started.

Signed-off-by: Jiafei Pan <[email protected]>

Author: JiafeiPan

drivers/interrupt_controller/Kconfig.gic

@@ -63,4 +63,14 @@ config GIC_V3_ITS
 	  that ITS uses dynamic memory, so HEAP_MEM_POOL_SIZE should be
 	  enough to allocate ITS tables (size is probed at runtime).
 
+config GIC_SAFE_CONFIG
+	bool "GIC Distributor Safe Configuration"
+	depends on GIC_V3
+	default n
+	help
+	  In case of multiple OSes running on different CPU Cores which share the
+	  same GIC controller, need to avoid the distributor re-configured to avoid
+	  crash the OS has already been started. With this enabled, it will bypass
+	  GIC distributor configuration if it has been configured by other OS.
+
 endif # CPU_CORTEX

drivers/interrupt_controller/intc_gicv3.c

@@ -447,6 +447,17 @@ static void gicv3_dist_init(void)
 	unsigned int idx;
 	mem_addr_t base = GIC_DIST_BASE;
 
+#ifdef CONFIG_GIC_SAFE_CONFIG
+	/*
+	 * Currently multiple OSes can run one the different CPU Cores which share single GIC,
+	 * but GIC distributor should avoid to be re-configured in order to avoid crash the
+	 * OSes has already been started.
+	 */
+	if (sys_read32(GICD_CTLR) & (BIT(GICD_CTLR_ENABLE_G0) | BIT(GICD_CTLR_ENABLE_G1NS))) {
+		return;
+	}
+#endif
+
 	num_ints = sys_read32(GICD_TYPER);
 	num_ints &= GICD_TYPER_ITLINESNUM_MASK;
 	num_ints = (num_ints + 1) << 5;