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/irqchip.h>
12 #include <linux/irqdomain.h>
13 #include <linux/of_irq.h>
14 #include <asm/traps.h>
15
16 #ifdef CONFIG_RAMKERNEL
17 typedef void (*h8300_vector)(void);
18
19 static const h8300_vector __initconst trap_table[] = {
20 0, 0, 0, 0,
21 _trace_break,
22 0, 0,
23 _nmi,
24 _system_call,
25 0, 0,
26 _trace_break,
27 };
28
get_vector_address(void)29 static unsigned long __init *get_vector_address(void)
30 {
31 unsigned long *rom_vector = CPU_VECTOR;
32 unsigned long base, tmp;
33 int vec_no;
34
35 base = rom_vector[EXT_IRQ0] & ADDR_MASK;
36
37 /* check romvector format */
38 for (vec_no = EXT_IRQ0 + 1; vec_no <= EXT_IRQ0+EXT_IRQS; vec_no++) {
39 if ((base+(vec_no - EXT_IRQ0)*4) !=
40 (rom_vector[vec_no] & ADDR_MASK))
41 return NULL;
42 }
43
44 /* ramvector base address */
45 base -= EXT_IRQ0*4;
46
47 /* writerble? */
48 tmp = ~(*(volatile unsigned long *)base);
49 (*(volatile unsigned long *)base) = tmp;
50 if ((*(volatile unsigned long *)base) != tmp)
51 return NULL;
52 return (unsigned long *)base;
53 }
54
setup_vector(void)55 static void __init setup_vector(void)
56 {
57 int i;
58 unsigned long *ramvec, *ramvec_p;
59 const h8300_vector *trap_entry;
60
61 ramvec = get_vector_address();
62 if (ramvec == NULL)
63 panic("interrupt vector serup failed.");
64 else
65 pr_debug("virtual vector at 0x%p\n", ramvec);
66
67 /* create redirect table */
68 ramvec_p = ramvec;
69 trap_entry = trap_table;
70 for (i = 0; i < NR_IRQS; i++) {
71 if (i < 12) {
72 if (*trap_entry)
73 *ramvec_p = VECTOR(*trap_entry);
74 ramvec_p++;
75 trap_entry++;
76 } else
77 *ramvec_p++ = REDIRECT(_interrupt_entry);
78 }
79 _interrupt_redirect_table = ramvec;
80 }
81 #else
setup_vector(void)82 void setup_vector(void)
83 {
84 /* noting do */
85 }
86 #endif
87
init_IRQ(void)88 void __init init_IRQ(void)
89 {
90 setup_vector();
91 irqchip_init();
92 }
93
do_IRQ(int irq)94 asmlinkage void do_IRQ(int irq)
95 {
96 irq_enter();
97 generic_handle_irq(irq);
98 irq_exit();
99 }
100