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-rw-r--r--arch/sh/kernel/cpu/irq/maskreg.c93
1 files changed, 93 insertions, 0 deletions
diff --git a/arch/sh/kernel/cpu/irq/maskreg.c b/arch/sh/kernel/cpu/irq/maskreg.c
new file mode 100644
index 000000000000..492db31b3cab
--- /dev/null
+++ b/arch/sh/kernel/cpu/irq/maskreg.c
@@ -0,0 +1,93 @@
1/*
2 * Interrupt handling for Simple external interrupt mask register
3 *
4 * Copyright (C) 2001 A&D Co., Ltd. <http://www.aandd.co.jp>
5 *
6 * This is for the machine which have single 16 bit register
7 * for masking external IRQ individually.
8 * Each bit of the register is for masking each interrupt.
9 *
10 * This file may be copied or modified under the terms of the GNU
11 * General Public License. See linux/COPYING for more information.
12 */
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/irq.h>
16#include <asm/system.h>
17#include <asm/io.h>
18
19/* address of external interrupt mask register */
20unsigned long irq_mask_register;
21
22/* forward declaration */
23static unsigned int startup_maskreg_irq(unsigned int irq);
24static void shutdown_maskreg_irq(unsigned int irq);
25static void enable_maskreg_irq(unsigned int irq);
26static void disable_maskreg_irq(unsigned int irq);
27static void mask_and_ack_maskreg(unsigned int);
28static void end_maskreg_irq(unsigned int irq);
29
30/* hw_interrupt_type */
31static struct hw_interrupt_type maskreg_irq_type = {
32 .typename = "Mask Register",
33 .startup = startup_maskreg_irq,
34 .shutdown = shutdown_maskreg_irq,
35 .enable = enable_maskreg_irq,
36 .disable = disable_maskreg_irq,
37 .ack = mask_and_ack_maskreg,
38 .end = end_maskreg_irq
39};
40
41/* actual implementatin */
42static unsigned int startup_maskreg_irq(unsigned int irq)
43{
44 enable_maskreg_irq(irq);
45 return 0; /* never anything pending */
46}
47
48static void shutdown_maskreg_irq(unsigned int irq)
49{
50 disable_maskreg_irq(irq);
51}
52
53static void disable_maskreg_irq(unsigned int irq)
54{
55 unsigned short val, mask = 0x01 << irq;
56
57 BUG_ON(!irq_mask_register);
58
59 /* Set "irq"th bit */
60 val = ctrl_inw(irq_mask_register);
61 val |= mask;
62 ctrl_outw(val, irq_mask_register);
63}
64
65static void enable_maskreg_irq(unsigned int irq)
66{
67 unsigned short val, mask = ~(0x01 << irq);
68
69 BUG_ON(!irq_mask_register);
70
71 /* Clear "irq"th bit */
72 val = ctrl_inw(irq_mask_register);
73 val &= mask;
74 ctrl_outw(val, irq_mask_register);
75}
76
77static void mask_and_ack_maskreg(unsigned int irq)
78{
79 disable_maskreg_irq(irq);
80}
81
82static void end_maskreg_irq(unsigned int irq)
83{
84 if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
85 enable_maskreg_irq(irq);
86}
87
88void make_maskreg_irq(unsigned int irq)
89{
90 disable_irq_nosync(irq);
91 irq_desc[irq].handler = &maskreg_irq_type;
92 disable_maskreg_irq(irq);
93}