1 /*
2 * linux/arch/h8300/kernel/irq.c
3 *
4 * Copyright 2007 Yoshinori Sato <ysato@users.sourceforge.jp>
5 */
6
7 #include <linux/module.h>
8 #include <linux/types.h>
9 #include <linux/kernel.h>
10 #include <linux/sched.h>
11 #include <linux/kernel_stat.h>
12 #include <linux/seq_file.h>
13 #include <linux/init.h>
14 #include <linux/random.h>
15 #include <linux/bootmem.h>
16 #include <linux/irq.h>
17 #include <linux/interrupt.h>
18
19 #include <asm/system.h>
20 #include <asm/traps.h>
21 #include <asm/io.h>
22 #include <asm/setup.h>
23 #include <asm/errno.h>
24
25 /*#define DEBUG*/
26
27 extern unsigned long *interrupt_redirect_table;
28 extern const int h8300_saved_vectors[];
29 extern const h8300_vector h8300_trap_table[];
30 int h8300_enable_irq_pin(unsigned int irq);
31 void h8300_disable_irq_pin(unsigned int irq);
32
33 #define CPU_VECTOR ((unsigned long *)0x000000)
34 #define ADDR_MASK (0xffffff)
35
is_ext_irq(unsigned int irq)36 static inline int is_ext_irq(unsigned int irq)
37 {
38 return (irq >= EXT_IRQ0 && irq <= (EXT_IRQ0 + EXT_IRQS));
39 }
40
h8300_enable_irq(struct irq_data * data)41 static void h8300_enable_irq(struct irq_data *data)
42 {
43 if (is_ext_irq(data->irq))
44 IER_REGS |= 1 << (data->irq - EXT_IRQ0);
45 }
46
h8300_disable_irq(struct irq_data * data)47 static void h8300_disable_irq(struct irq_data *data)
48 {
49 if (is_ext_irq(data->irq))
50 IER_REGS &= ~(1 << (data->irq - EXT_IRQ0));
51 }
52
h8300_startup_irq(struct irq_data * data)53 static unsigned int h8300_startup_irq(struct irq_data *data)
54 {
55 if (is_ext_irq(data->irq))
56 return h8300_enable_irq_pin(data->irq);
57 else
58 return 0;
59 }
60
h8300_shutdown_irq(struct irq_data * data)61 static void h8300_shutdown_irq(struct irq_data *data)
62 {
63 if (is_ext_irq(data->irq))
64 h8300_disable_irq_pin(data->irq);
65 }
66
67 /*
68 * h8300 interrupt controller implementation
69 */
70 struct irq_chip h8300irq_chip = {
71 .name = "H8300-INTC",
72 .irq_startup = h8300_startup_irq,
73 .irq_shutdown = h8300_shutdown_irq,
74 .irq_enable = h8300_enable_irq,
75 .irq_disable = h8300_disable_irq,
76 };
77
78 #if defined(CONFIG_RAMKERNEL)
get_vector_address(void)79 static unsigned long __init *get_vector_address(void)
80 {
81 unsigned long *rom_vector = CPU_VECTOR;
82 unsigned long base,tmp;
83 int vec_no;
84
85 base = rom_vector[EXT_IRQ0] & ADDR_MASK;
86
87 /* check romvector format */
88 for (vec_no = EXT_IRQ1; vec_no <= EXT_IRQ0+EXT_IRQS; vec_no++) {
89 if ((base+(vec_no - EXT_IRQ0)*4) != (rom_vector[vec_no] & ADDR_MASK))
90 return NULL;
91 }
92
93 /* ramvector base address */
94 base -= EXT_IRQ0*4;
95
96 /* writerble check */
97 tmp = ~(*(volatile unsigned long *)base);
98 (*(volatile unsigned long *)base) = tmp;
99 if ((*(volatile unsigned long *)base) != tmp)
100 return NULL;
101 return (unsigned long *)base;
102 }
103
setup_vector(void)104 static void __init setup_vector(void)
105 {
106 int i;
107 unsigned long *ramvec,*ramvec_p;
108 const h8300_vector *trap_entry;
109 const int *saved_vector;
110
111 ramvec = get_vector_address();
112 if (ramvec == NULL)
113 panic("interrupt vector serup failed.");
114 else
115 printk(KERN_INFO "virtual vector at 0x%08lx\n",(unsigned long)ramvec);
116
117 /* create redirect table */
118 ramvec_p = ramvec;
119 trap_entry = h8300_trap_table;
120 saved_vector = h8300_saved_vectors;
121 for ( i = 0; i < NR_IRQS; i++) {
122 if (i == *saved_vector) {
123 ramvec_p++;
124 saved_vector++;
125 } else {
126 if ( i < NR_TRAPS ) {
127 if (*trap_entry)
128 *ramvec_p = VECTOR(*trap_entry);
129 ramvec_p++;
130 trap_entry++;
131 } else
132 *ramvec_p++ = REDIRECT(interrupt_entry);
133 }
134 }
135 interrupt_redirect_table = ramvec;
136 #ifdef DEBUG
137 ramvec_p = ramvec;
138 for (i = 0; i < NR_IRQS; i++) {
139 if ((i % 8) == 0)
140 printk(KERN_DEBUG "\n%p: ",ramvec_p);
141 printk(KERN_DEBUG "%p ",*ramvec_p);
142 ramvec_p++;
143 }
144 printk(KERN_DEBUG "\n");
145 #endif
146 }
147 #else
148 #define setup_vector() do { } while(0)
149 #endif
150
init_IRQ(void)151 void __init init_IRQ(void)
152 {
153 int c;
154
155 setup_vector();
156
157 for (c = 0; c < NR_IRQS; c++)
158 irq_set_chip_and_handler(c, &h8300irq_chip, handle_simple_irq);
159 }
160
do_IRQ(int irq)161 asmlinkage void do_IRQ(int irq)
162 {
163 irq_enter();
164 generic_handle_irq(irq);
165 irq_exit();
166 }
167