v4.19.13 snapshot.
diff --git a/arch/mips/loongson64/common/irq.c b/arch/mips/loongson64/common/irq.c
new file mode 100644
index 0000000..d36d969
--- /dev/null
+++ b/arch/mips/loongson64/common/irq.c
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2007 Lemote Inc. & Institute of Computing Technology
+ * Author: Fuxin Zhang, zhangfx@lemote.com
+ *
+ *  This program is free software; you can redistribute	 it and/or modify it
+ *  under  the terms of	 the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the	License, or (at your
+ *  option) any later version.
+ */
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+
+#include <loongson.h>
+/*
+ * the first level int-handler will jump here if it is a bonito irq
+ */
+void bonito_irqdispatch(void)
+{
+	u32 int_status;
+	int i;
+
+	/* workaround the IO dma problem: let cpu looping to allow DMA finish */
+	int_status = LOONGSON_INTISR;
+	while (int_status & (1 << 10)) {
+		udelay(1);
+		int_status = LOONGSON_INTISR;
+	}
+
+	/* Get pending sources, masked by current enables */
+	int_status = LOONGSON_INTISR & LOONGSON_INTEN;
+
+	if (int_status) {
+		i = __ffs(int_status);
+		do_IRQ(LOONGSON_IRQ_BASE + i);
+	}
+}
+
+asmlinkage void plat_irq_dispatch(void)
+{
+	unsigned int pending;
+
+	pending = read_c0_cause() & read_c0_status() & ST0_IM;
+
+	/* machine-specific plat_irq_dispatch */
+	mach_irq_dispatch(pending);
+}
+
+void __init arch_init_irq(void)
+{
+	/*
+	 * Clear all of the interrupts while we change the able around a bit.
+	 * int-handler is not on bootstrap
+	 */
+	clear_c0_status(ST0_IM | ST0_BEV);
+
+	/* no steer */
+	LOONGSON_INTSTEER = 0;
+
+	/*
+	 * Mask out all interrupt by writing "1" to all bit position in
+	 * the interrupt reset reg.
+	 */
+	LOONGSON_INTENCLR = ~0;
+
+	/* machine specific irq init */
+	mach_init_irq();
+}