sandbox: add handler for exceptions

Add a handler for SIGILL, SIGBUS, SIGSEGV.

When an exception occurs print the program counter and the loaded
UEFI binaries and reset the system if CONFIG_SANDBOX_CRASH_RESET=y
or exit to the OS otherwise.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/sandbox/lib/interrupts.c b/arch/sandbox/lib/interrupts.c
index 21f761a..9c2c60b 100644
--- a/arch/sandbox/lib/interrupts.c
+++ b/arch/sandbox/lib/interrupts.c
@@ -6,7 +6,13 @@
  */
 
 #include <common.h>
+#include <efi_loader.h>
 #include <irq_func.h>
+#include <os.h>
+#include <asm-generic/signal.h>
+#include <asm/u-boot-sandbox.h>
+
+DECLARE_GLOBAL_DATA_PTR;
 
 int interrupt_init(void)
 {
@@ -21,3 +27,32 @@
 {
 	return 0;
 }
+
+void os_signal_action(int sig, unsigned long pc)
+{
+	efi_restore_gd();
+
+	switch (sig) {
+	case SIGILL:
+		printf("\nIllegal instruction\n");
+		break;
+	case SIGBUS:
+		printf("\nBus error\n");
+		break;
+	case SIGSEGV:
+		printf("\nSegmentation violation\n");
+		break;
+	default:
+		break;
+	}
+	printf("pc = 0x%lx, ", pc);
+	printf("pc_reloc = 0x%lx\n\n", pc - gd->reloc_off);
+	efi_print_image_infos((void *)pc);
+
+	if (IS_ENABLED(CONFIG_SANDBOX_CRASH_RESET)) {
+		printf("resetting ...\n\n");
+		sandbox_reset();
+	} else {
+		sandbox_exit();
+	}
+}