v4.19.13 snapshot.
diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c
new file mode 100644
index 0000000..ba150c7
--- /dev/null
+++ b/arch/mips/kernel/irq.c
@@ -0,0 +1,109 @@
+/*
+ * 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.
+ *
+ * Code to handle x86 style IRQs plus some generic interrupt stuff.
+ *
+ * Copyright (C) 1992 Linus Torvalds
+ * Copyright (C) 1994 - 2000 Ralf Baechle
+ */
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <linux/proc_fs.h>
+#include <linux/mm.h>
+#include <linux/random.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/kallsyms.h>
+#include <linux/kgdb.h>
+#include <linux/ftrace.h>
+
+#include <linux/atomic.h>
+#include <linux/uaccess.h>
+
+void *irq_stack[NR_CPUS];
+
+/*
+ * 'what should we do if we get a hw irq event on an illegal vector'.
+ * each architecture has to answer this themselves.
+ */
+void ack_bad_irq(unsigned int irq)
+{
+ printk("unexpected IRQ # %d\n", irq);
+}
+
+atomic_t irq_err_count;
+
+int arch_show_interrupts(struct seq_file *p, int prec)
+{
+ seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
+ return 0;
+}
+
+asmlinkage void spurious_interrupt(void)
+{
+ atomic_inc(&irq_err_count);
+}
+
+void __init init_IRQ(void)
+{
+ int i;
+
+ for (i = 0; i < NR_IRQS; i++)
+ irq_set_noprobe(i);
+
+ if (cpu_has_veic)
+ clear_c0_status(ST0_IM);
+
+ arch_init_irq();
+
+ for_each_possible_cpu(i) {
+ int irq_pages = IRQ_STACK_SIZE / PAGE_SIZE;
+ void *s = (void *)__get_free_pages(GFP_KERNEL, irq_pages);
+
+ irq_stack[i] = s;
+ pr_debug("CPU%d IRQ stack at 0x%p - 0x%p\n", i,
+ irq_stack[i], irq_stack[i] + IRQ_STACK_SIZE);
+ }
+}
+
+#ifdef CONFIG_DEBUG_STACKOVERFLOW
+static inline void check_stack_overflow(void)
+{
+ unsigned long sp;
+
+ __asm__ __volatile__("move %0, $sp" : "=r" (sp));
+ sp &= THREAD_MASK;
+
+ /*
+ * Check for stack overflow: is there less than STACK_WARN free?
+ * STACK_WARN is defined as 1/8 of THREAD_SIZE by default.
+ */
+ if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {
+ printk("do_IRQ: stack overflow: %ld\n",
+ sp - sizeof(struct thread_info));
+ dump_stack();
+ }
+}
+#else
+static inline void check_stack_overflow(void) {}
+#endif
+
+
+/*
+ * do_IRQ handles all normal device IRQ's (the special
+ * SMP cross-CPU interrupts have their own specific
+ * handlers).
+ */
+void __irq_entry do_IRQ(unsigned int irq)
+{
+ irq_enter();
+ check_stack_overflow();
+ generic_handle_irq(irq);
+ irq_exit();
+}
+