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
18#include <asm/system.h>
19#include <asm/traps.h>
20#include <asm/io.h>
21#include <asm/setup.h>
22#include <asm/errno.h>
23
24/*#define DEBUG*/
25
26extern unsigned long *interrupt_redirect_table;
27extern const int h8300_saved_vectors[];
28extern const unsigned long h8300_trap_table[];
29int h8300_enable_irq_pin(unsigned int irq);
30void h8300_disable_irq_pin(unsigned int irq);
31
32#define CPU_VECTOR ((unsigned long *)0x000000)
33#define ADDR_MASK (0xffffff)
34
35static inline int is_ext_irq(unsigned int irq)
36{
37	return (irq >= EXT_IRQ0 && irq <= (EXT_IRQ0 + EXT_IRQS));
38}
39
40static void h8300_enable_irq(unsigned int irq)
41{
42	if (is_ext_irq(irq))
43		IER_REGS |= 1 << (irq - EXT_IRQ0);
44}
45
46static void h8300_disable_irq(unsigned int irq)
47{
48	if (is_ext_irq(irq))
49		IER_REGS &= ~(1 << (irq - EXT_IRQ0));
50}
51
52static void h8300_end_irq(unsigned int irq)
53{
54}
55
56static unsigned int h8300_startup_irq(unsigned int irq)
57{
58	if (is_ext_irq(irq))
59		return h8300_enable_irq_pin(irq);
60	else
61		return 0;
62}
63
64static void h8300_shutdown_irq(unsigned int irq)
65{
66	if (is_ext_irq(irq))
67		h8300_disable_irq_pin(irq);
68}
69
70/*
71 * h8300 interrupt controler implementation
72 */
73struct irq_chip h8300irq_chip = {
74	.name		= "H8300-INTC",
75	.startup	= h8300_startup_irq,
76	.shutdown	= h8300_shutdown_irq,
77	.enable		= h8300_enable_irq,
78	.disable	= h8300_disable_irq,
79	.ack		= NULL,
80	.end		= h8300_end_irq,
81};
82
83void ack_bad_irq(unsigned int irq)
84{
85	printk("unexpected IRQ trap at vector %02x\n", irq);
86}
87
88#if defined(CONFIG_RAMKERNEL)
89static unsigned long __init *get_vector_address(void)
90{
91	unsigned long *rom_vector = CPU_VECTOR;
92	unsigned long base,tmp;
93	int vec_no;
94
95	base = rom_vector[EXT_IRQ0] & ADDR_MASK;
96
97	/* check romvector format */
98	for (vec_no = EXT_IRQ1; vec_no <= EXT_IRQ0+EXT_IRQS; vec_no++) {
99		if ((base+(vec_no - EXT_IRQ0)*4) != (rom_vector[vec_no] & ADDR_MASK))
100			return NULL;
101	}
102
103	/* ramvector base address */
104	base -= EXT_IRQ0*4;
105
106	/* writerble check */
107	tmp = ~(*(volatile unsigned long *)base);
108	(*(volatile unsigned long *)base) = tmp;
109	if ((*(volatile unsigned long *)base) != tmp)
110		return NULL;
111	return (unsigned long *)base;
112}
113
114static void __init setup_vector(void)
115{
116	int i;
117	unsigned long *ramvec,*ramvec_p;
118	const unsigned long *trap_entry;
119	const int *saved_vector;
120
121	ramvec = get_vector_address();
122	if (ramvec == NULL)
123		panic("interrupt vector serup failed.");
124	else
125		printk(KERN_INFO "virtual vector at 0x%08lx\n",(unsigned long)ramvec);
126
127	/* create redirect table */
128	ramvec_p = ramvec;
129	trap_entry = h8300_trap_table;
130	saved_vector = h8300_saved_vectors;
131	for ( i = 0; i < NR_IRQS; i++) {
132		if (i == *saved_vector) {
133			ramvec_p++;
134			saved_vector++;
135		} else {
136			if ( i < NR_TRAPS ) {
137				if (*trap_entry)
138					*ramvec_p = VECTOR(*trap_entry);
139				ramvec_p++;
140				trap_entry++;
141			} else
142				*ramvec_p++ = REDIRECT(interrupt_entry);
143		}
144	}
145	interrupt_redirect_table = ramvec;
146#ifdef DEBUG
147	ramvec_p = ramvec;
148	for (i = 0; i < NR_IRQS; i++) {
149		if ((i % 8) == 0)
150			printk(KERN_DEBUG "\n%p: ",ramvec_p);
151		printk(KERN_DEBUG "%p ",*ramvec_p);
152		ramvec_p++;
153	}
154	printk(KERN_DEBUG "\n");
155#endif
156}
157#else
158#define setup_vector() do { } while(0)
159#endif
160
161void __init init_IRQ(void)
162{
163	int c;
164
165	setup_vector();
166
167	for (c = 0; c < NR_IRQS; c++) {
168		irq_desc[c].status = IRQ_DISABLED;
169		irq_desc[c].action = NULL;
170		irq_desc[c].depth = 1;
171		irq_desc[c].chip = &h8300irq_chip;
172	}
173}
174
175asmlinkage void do_IRQ(int irq)
176{
177	irq_enter();
178	__do_IRQ(irq);
179	irq_exit();
180}
181
182#if defined(CONFIG_PROC_FS)
183int show_interrupts(struct seq_file *p, void *v)
184{
185	int i = *(loff_t *) v, j;
186	struct irqaction * action;
187	unsigned long flags;
188
189	if (i == 0)
190		seq_puts(p, "           CPU0");
191
192	if (i < NR_IRQS) {
193		spin_lock_irqsave(&irq_desc[i].lock, flags);
194		action = irq_desc[i].action;
195		if (!action)
196			goto unlock;
197		seq_printf(p, "%3d: ",i);
198		seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
199		seq_printf(p, " %14s", irq_desc[i].chip->name);
200		seq_printf(p, "-%-8s", irq_desc[i].name);
201		seq_printf(p, "  %s", action->name);
202
203		for (action=action->next; action; action = action->next)
204			seq_printf(p, ", %s", action->name);
205		seq_putc(p, '\n');
206unlock:
207		spin_unlock_irqrestore(&irq_desc[i].lock, flags);
208	}
209	return 0;
210}
211#endif
212