v4.19.13 snapshot.
diff --git a/arch/mips/fw/arc/init.c b/arch/mips/fw/arc/init.c
new file mode 100644
index 0000000..0085559
--- /dev/null
+++ b/arch/mips/fw/arc/init.c
@@ -0,0 +1,59 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * PROM library initialisation code.
+ *
+ * Copyright (C) 1996 David S. Miller (davem@davemloft.net)
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+
+#include <asm/bootinfo.h>
+#include <asm/sgialib.h>
+#include <asm/smp-ops.h>
+
+#undef DEBUG_PROM_INIT
+
+/* Master romvec interface. */
+struct linux_romvec *romvec;
+int prom_argc;
+LONG *_prom_argv, *_prom_envp;
+
+void __init prom_init(void)
+{
+	PSYSTEM_PARAMETER_BLOCK pb = PROMBLOCK;
+
+	romvec = ROMVECTOR;
+
+	prom_argc = fw_arg0;
+	_prom_argv = (LONG *) fw_arg1;
+	_prom_envp = (LONG *) fw_arg2;
+
+	if (pb->magic != 0x53435241) {
+		printk(KERN_CRIT "Aieee, bad prom vector magic %08lx\n",
+		       (unsigned long) pb->magic);
+		while(1)
+			;
+	}
+
+	prom_init_cmdline();
+	prom_identify_arch();
+	printk(KERN_INFO "PROMLIB: ARC firmware Version %d Revision %d\n",
+	       pb->ver, pb->rev);
+	prom_meminit();
+
+#ifdef DEBUG_PROM_INIT
+	pr_info("Press a key to reboot\n");
+	ArcRead(0, &c, 1, &cnt);
+	ArcEnterInteractiveMode();
+#endif
+#ifdef CONFIG_SGI_IP27
+	{
+		extern const struct plat_smp_ops ip27_smp_ops;
+
+		register_smp_ops(&ip27_smp_ops);
+	}
+#endif
+}