xref: /linux/arch/um/kernel/irq.c (revision 54a8a2220c936a47840c9a3d74910c5a56fae2ed)
1 /*
2  * Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
3  * Licensed under the GPL
4  * Derived (i.e. mostly copied) from arch/i386/kernel/irq.c:
5  *	Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
6  */
7 
8 #include "linux/config.h"
9 #include "linux/kernel.h"
10 #include "linux/module.h"
11 #include "linux/smp.h"
12 #include "linux/kernel_stat.h"
13 #include "linux/interrupt.h"
14 #include "linux/random.h"
15 #include "linux/slab.h"
16 #include "linux/file.h"
17 #include "linux/proc_fs.h"
18 #include "linux/init.h"
19 #include "linux/seq_file.h"
20 #include "linux/profile.h"
21 #include "linux/hardirq.h"
22 #include "asm/irq.h"
23 #include "asm/hw_irq.h"
24 #include "asm/atomic.h"
25 #include "asm/signal.h"
26 #include "asm/system.h"
27 #include "asm/errno.h"
28 #include "asm/uaccess.h"
29 #include "user_util.h"
30 #include "kern_util.h"
31 #include "irq_user.h"
32 #include "irq_kern.h"
33 #include "os.h"
34 
35 /*
36  * Generic, controller-independent functions:
37  */
38 
39 int show_interrupts(struct seq_file *p, void *v)
40 {
41 	int i = *(loff_t *) v, j;
42 	struct irqaction * action;
43 	unsigned long flags;
44 
45 	if (i == 0) {
46 		seq_printf(p, "           ");
47 		for_each_online_cpu(j)
48 			seq_printf(p, "CPU%d       ",j);
49 		seq_putc(p, '\n');
50 	}
51 
52 	if (i < NR_IRQS) {
53 		spin_lock_irqsave(&irq_desc[i].lock, flags);
54 		action = irq_desc[i].action;
55 		if (!action)
56 			goto skip;
57 		seq_printf(p, "%3d: ",i);
58 #ifndef CONFIG_SMP
59 		seq_printf(p, "%10u ", kstat_irqs(i));
60 #else
61 		for_each_online_cpu(j)
62 			seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
63 #endif
64 		seq_printf(p, " %14s", irq_desc[i].handler->typename);
65 		seq_printf(p, "  %s", action->name);
66 
67 		for (action=action->next; action; action = action->next)
68 			seq_printf(p, ", %s", action->name);
69 
70 		seq_putc(p, '\n');
71 skip:
72 		spin_unlock_irqrestore(&irq_desc[i].lock, flags);
73 	} else if (i == NR_IRQS) {
74 		seq_putc(p, '\n');
75 	}
76 
77 	return 0;
78 }
79 
80 /*
81  * do_IRQ handles all normal device IRQ's (the special
82  * SMP cross-CPU interrupts have their own specific
83  * handlers).
84  */
85 unsigned int do_IRQ(int irq, union uml_pt_regs *regs)
86 {
87        irq_enter();
88        __do_IRQ(irq, (struct pt_regs *) regs);
89        irq_exit();
90        return 1;
91 }
92 
93 int um_request_irq(unsigned int irq, int fd, int type,
94 		   irqreturn_t (*handler)(int, void *, struct pt_regs *),
95 		   unsigned long irqflags, const char * devname,
96 		   void *dev_id)
97 {
98 	int err;
99 
100 	err = request_irq(irq, handler, irqflags, devname, dev_id);
101 	if(err)
102 		return(err);
103 
104 	if(fd != -1)
105 		err = activate_fd(irq, fd, type, dev_id);
106 	return(err);
107 }
108 EXPORT_SYMBOL(um_request_irq);
109 EXPORT_SYMBOL(reactivate_fd);
110 
111 static DEFINE_SPINLOCK(irq_spinlock);
112 
113 unsigned long irq_lock(void)
114 {
115 	unsigned long flags;
116 
117 	spin_lock_irqsave(&irq_spinlock, flags);
118 	return(flags);
119 }
120 
121 void irq_unlock(unsigned long flags)
122 {
123 	spin_unlock_irqrestore(&irq_spinlock, flags);
124 }
125 
126 /* hw_interrupt_type must define (startup || enable) &&
127  * (shutdown || disable) && end */
128 static void dummy(unsigned int irq)
129 {
130 }
131 
132 /* This is used for everything else than the timer. */
133 static struct hw_interrupt_type normal_irq_type = {
134 	.typename = "SIGIO",
135 	.release = free_irq_by_irq_and_dev,
136 	.disable = dummy,
137 	.enable = dummy,
138 	.ack = dummy,
139 	.end = dummy
140 };
141 
142 static struct hw_interrupt_type SIGVTALRM_irq_type = {
143 	.typename = "SIGVTALRM",
144 	.release = free_irq_by_irq_and_dev,
145 	.shutdown = dummy, /* never called */
146 	.disable = dummy,
147 	.enable = dummy,
148 	.ack = dummy,
149 	.end = dummy
150 };
151 
152 void __init init_IRQ(void)
153 {
154 	int i;
155 
156 	irq_desc[TIMER_IRQ].status = IRQ_DISABLED;
157 	irq_desc[TIMER_IRQ].action = NULL;
158 	irq_desc[TIMER_IRQ].depth = 1;
159 	irq_desc[TIMER_IRQ].handler = &SIGVTALRM_irq_type;
160 	enable_irq(TIMER_IRQ);
161 	for(i=1;i<NR_IRQS;i++){
162 		irq_desc[i].status = IRQ_DISABLED;
163 		irq_desc[i].action = NULL;
164 		irq_desc[i].depth = 1;
165 		irq_desc[i].handler = &normal_irq_type;
166 		enable_irq(i);
167 	}
168 }
169 
170 int init_aio_irq(int irq, char *name, irqreturn_t (*handler)(int, void *,
171 							     struct pt_regs *))
172 {
173 	int fds[2], err;
174 
175 	err = os_pipe(fds, 1, 1);
176 	if(err){
177 		printk("init_aio_irq - os_pipe failed, err = %d\n", -err);
178 		goto out;
179 	}
180 
181 	err = um_request_irq(irq, fds[0], IRQ_READ, handler,
182 			     SA_INTERRUPT | SA_SAMPLE_RANDOM, name,
183 			     (void *) (long) fds[0]);
184 	if(err){
185 		printk("init_aio_irq - : um_request_irq failed, err = %d\n",
186 		       err);
187 		goto out_close;
188 	}
189 
190 	err = fds[1];
191 	goto out;
192 
193  out_close:
194 	os_close_file(fds[0]);
195 	os_close_file(fds[1]);
196  out:
197 	return(err);
198 }
199