ARM: shmobile: sh73a0: Add restart callback

Port the sh73a0 restart handling from the kzm9g-legacy board code to the
generic sh73a0 code.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>

arch/arm/mach-shmobile/setup-sh73a0.c

@@ -775,6 +775,13 @@ void __init sh73a0_add_standard_devices_dt(void)
 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
 }
 
+#define RESCNT2 IOMEM(0xe6188020)
+static void sh73a0_restart(enum reboot_mode mode, const char *cmd)
+{
+	/* Do soft power on reset */
+	writel((1 << 31), RESCNT2);
+}
+
 static const char *sh73a0_boards_compat_dt[] __initdata = {
 	"renesas,sh73a0",
 	NULL,
@@ -786,6 +793,7 @@ DT_MACHINE_START(SH73A0_DT, "Generic SH73A0 (Flattened Device Tree)")
 	.init_early	= sh73a0_init_delay,
 	.init_machine	= sh73a0_add_standard_devices_dt,
 	.init_late	= shmobile_init_late,
+	.restart	= sh73a0_restart,
 	.dt_compat	= sh73a0_boards_compat_dt,
 MACHINE_END
 #endif /* CONFIG_USE_OF */