1 /*
2  * Copyright (C) 2003 Ralf Baechle
3  *
4  * This program is free software; you can redistribute  it and/or modify it
5  * under  the terms of  the GNU General  Public License as published by the
6  * Free Software Foundation;  either version 2 of the  License, or (at your
7  * option) any later version.
8  *
9  * Handler for RM9000 extended interrupts.  These are a non-standard
10  * feature so we handle them separately from standard interrupts.
11  */
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/irq.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 
18 #include <asm/irq_cpu.h>
19 #include <asm/mipsregs.h>
20 #include <asm/system.h>
21 
unmask_rm9k_irq(struct irq_data * d)22 static inline void unmask_rm9k_irq(struct irq_data *d)
23 {
24 	set_c0_intcontrol(0x1000 << (d->irq - RM9K_CPU_IRQ_BASE));
25 }
26 
mask_rm9k_irq(struct irq_data * d)27 static inline void mask_rm9k_irq(struct irq_data *d)
28 {
29 	clear_c0_intcontrol(0x1000 << (d->irq - RM9K_CPU_IRQ_BASE));
30 }
31 
rm9k_cpu_irq_enable(struct irq_data * d)32 static inline void rm9k_cpu_irq_enable(struct irq_data *d)
33 {
34 	unsigned long flags;
35 
36 	local_irq_save(flags);
37 	unmask_rm9k_irq(d);
38 	local_irq_restore(flags);
39 }
40 
41 /*
42  * Performance counter interrupts are global on all processors.
43  */
local_rm9k_perfcounter_irq_startup(void * args)44 static void local_rm9k_perfcounter_irq_startup(void *args)
45 {
46 	rm9k_cpu_irq_enable(args);
47 }
48 
rm9k_perfcounter_irq_startup(struct irq_data * d)49 static unsigned int rm9k_perfcounter_irq_startup(struct irq_data *d)
50 {
51 	on_each_cpu(local_rm9k_perfcounter_irq_startup, d, 1);
52 
53 	return 0;
54 }
55 
local_rm9k_perfcounter_irq_shutdown(void * args)56 static void local_rm9k_perfcounter_irq_shutdown(void *args)
57 {
58 	unsigned long flags;
59 
60 	local_irq_save(flags);
61 	mask_rm9k_irq(args);
62 	local_irq_restore(flags);
63 }
64 
rm9k_perfcounter_irq_shutdown(struct irq_data * d)65 static void rm9k_perfcounter_irq_shutdown(struct irq_data *d)
66 {
67 	on_each_cpu(local_rm9k_perfcounter_irq_shutdown, d, 1);
68 }
69 
70 static struct irq_chip rm9k_irq_controller = {
71 	.name = "RM9000",
72 	.irq_ack = mask_rm9k_irq,
73 	.irq_mask = mask_rm9k_irq,
74 	.irq_mask_ack = mask_rm9k_irq,
75 	.irq_unmask = unmask_rm9k_irq,
76 	.irq_eoi = unmask_rm9k_irq
77 };
78 
79 static struct irq_chip rm9k_perfcounter_irq = {
80 	.name = "RM9000",
81 	.irq_startup = rm9k_perfcounter_irq_startup,
82 	.irq_shutdown = rm9k_perfcounter_irq_shutdown,
83 	.irq_ack = mask_rm9k_irq,
84 	.irq_mask = mask_rm9k_irq,
85 	.irq_mask_ack = mask_rm9k_irq,
86 	.irq_unmask = unmask_rm9k_irq,
87 };
88 
89 unsigned int rm9000_perfcount_irq;
90 
91 EXPORT_SYMBOL(rm9000_perfcount_irq);
92 
rm9k_cpu_irq_init(void)93 void __init rm9k_cpu_irq_init(void)
94 {
95 	int base = RM9K_CPU_IRQ_BASE;
96 	int i;
97 
98 	clear_c0_intcontrol(0x0000f000);		/* Mask all */
99 
100 	for (i = base; i < base + 4; i++)
101 		irq_set_chip_and_handler(i, &rm9k_irq_controller,
102 					 handle_level_irq);
103 
104 	rm9000_perfcount_irq = base + 1;
105 	irq_set_chip_and_handler(rm9000_perfcount_irq, &rm9k_perfcounter_irq,
106 				 handle_percpu_irq);
107 }
108