1// SPDX-License-Identifier: GPL-2.0
 2/*
 3 * linux/arch/h8300/kernel/irq.c
 4 *
 5 * Copyright 2014-2015 Yoshinori Sato <ysato@users.sourceforge.jp>
 6 */
 7
 8#include <linux/init.h>
 9#include <linux/interrupt.h>
10#include <linux/irq.h>
11#include <linux/irqdomain.h>
12#include <linux/of_irq.h>
13#include <asm/traps.h>
14
15#ifdef CONFIG_RAMKERNEL
16typedef void (*h8300_vector)(void);
17
18static const h8300_vector __initconst trap_table[] = {
19	0, 0, 0, 0,
20	_trace_break,
21	0, 0,
22	_nmi,
23	_system_call,
24	0, 0,
25	_trace_break,
26};
27
28static unsigned long __init *get_vector_address(void)
29{
30	unsigned long *rom_vector = CPU_VECTOR;
31	unsigned long base, tmp;
32	int vec_no;
33
34	base = rom_vector[EXT_IRQ0] & ADDR_MASK;
35
36	/* check romvector format */
37	for (vec_no = EXT_IRQ0 + 1; vec_no <= EXT_IRQ0+EXT_IRQS; vec_no++) {
38		if ((base+(vec_no - EXT_IRQ0)*4) !=
39		    (rom_vector[vec_no] & ADDR_MASK))
40			return NULL;
41	}
42
43	/* ramvector base address */
44	base -= EXT_IRQ0*4;
45
46	/* writerble? */
47	tmp = ~(*(volatile unsigned long *)base);
48	(*(volatile unsigned long *)base) = tmp;
49	if ((*(volatile unsigned long *)base) != tmp)
50		return NULL;
51	return (unsigned long *)base;
52}
53
54static void __init setup_vector(void)
55{
56	int i;
57	unsigned long *ramvec, *ramvec_p;
58	const h8300_vector *trap_entry;
59
60	ramvec = get_vector_address();
61	if (ramvec == NULL)
62		panic("interrupt vector serup failed.");
63	else
64		pr_debug("virtual vector at 0x%p\n", ramvec);
65
66	/* create redirect table */
67	ramvec_p = ramvec;
68	trap_entry = trap_table;
69	for (i = 0; i < NR_IRQS; i++) {
70		if (i < 12) {
71			if (*trap_entry)
72				*ramvec_p = VECTOR(*trap_entry);
73			ramvec_p++;
74			trap_entry++;
75		} else
76			*ramvec_p++ = REDIRECT(_interrupt_entry);
77	}
78	_interrupt_redirect_table = ramvec;
79}
80#else
81void setup_vector(void)
82{
83	/* noting do */
84}
85#endif
86
87void __init init_IRQ(void)
88{
89	setup_vector();
90	irqchip_init();
91}
92
93asmlinkage void do_IRQ(int irq)
94{
95	irq_enter();
96	generic_handle_irq(irq);
97	irq_exit();
98}