1 /*
2 * linux/arch/arm/mach-sa1100/irq.c
3 *
4 * Copyright (C) 1999-2001 Nicolas Pitre
5 *
6 * Generic IRQ handling for the SA11x0, GPIO 11-27 IRQ demultiplexing.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/interrupt.h>
15 #include <linux/io.h>
16 #include <linux/irq.h>
17 #include <linux/irqdomain.h>
18 #include <linux/ioport.h>
19 #include <linux/syscore_ops.h>
20
21 #include <mach/hardware.h>
22 #include <mach/irqs.h>
23 #include <asm/mach/irq.h>
24 #include <asm/exception.h>
25
26 #include "generic.h"
27
28
29 /*
30 * We don't need to ACK IRQs on the SA1100 unless they're GPIOs
31 * this is for internal IRQs i.e. from IRQ LCD to RTCAlrm.
32 */
sa1100_mask_irq(struct irq_data * d)33 static void sa1100_mask_irq(struct irq_data *d)
34 {
35 ICMR &= ~BIT(d->hwirq);
36 }
37
sa1100_unmask_irq(struct irq_data * d)38 static void sa1100_unmask_irq(struct irq_data *d)
39 {
40 ICMR |= BIT(d->hwirq);
41 }
42
43 /*
44 * Apart form GPIOs, only the RTC alarm can be a wakeup event.
45 */
sa1100_set_wake(struct irq_data * d,unsigned int on)46 static int sa1100_set_wake(struct irq_data *d, unsigned int on)
47 {
48 if (BIT(d->hwirq) == IC_RTCAlrm) {
49 if (on)
50 PWER |= PWER_RTC;
51 else
52 PWER &= ~PWER_RTC;
53 return 0;
54 }
55 return -EINVAL;
56 }
57
58 static struct irq_chip sa1100_normal_chip = {
59 .name = "SC",
60 .irq_ack = sa1100_mask_irq,
61 .irq_mask = sa1100_mask_irq,
62 .irq_unmask = sa1100_unmask_irq,
63 .irq_set_wake = sa1100_set_wake,
64 };
65
sa1100_normal_irqdomain_map(struct irq_domain * d,unsigned int irq,irq_hw_number_t hwirq)66 static int sa1100_normal_irqdomain_map(struct irq_domain *d,
67 unsigned int irq, irq_hw_number_t hwirq)
68 {
69 irq_set_chip_and_handler(irq, &sa1100_normal_chip,
70 handle_level_irq);
71 set_irq_flags(irq, IRQF_VALID);
72
73 return 0;
74 }
75
76 static struct irq_domain_ops sa1100_normal_irqdomain_ops = {
77 .map = sa1100_normal_irqdomain_map,
78 .xlate = irq_domain_xlate_onetwocell,
79 };
80
81 static struct irq_domain *sa1100_normal_irqdomain;
82
83 static struct resource irq_resource =
84 DEFINE_RES_MEM_NAMED(0x90050000, SZ_64K, "irqs");
85
86 static struct sa1100irq_state {
87 unsigned int saved;
88 unsigned int icmr;
89 unsigned int iclr;
90 unsigned int iccr;
91 } sa1100irq_state;
92
sa1100irq_suspend(void)93 static int sa1100irq_suspend(void)
94 {
95 struct sa1100irq_state *st = &sa1100irq_state;
96
97 st->saved = 1;
98 st->icmr = ICMR;
99 st->iclr = ICLR;
100 st->iccr = ICCR;
101
102 /*
103 * Disable all GPIO-based interrupts.
104 */
105 ICMR &= ~(IC_GPIO11_27|IC_GPIO10|IC_GPIO9|IC_GPIO8|IC_GPIO7|
106 IC_GPIO6|IC_GPIO5|IC_GPIO4|IC_GPIO3|IC_GPIO2|
107 IC_GPIO1|IC_GPIO0);
108
109 return 0;
110 }
111
sa1100irq_resume(void)112 static void sa1100irq_resume(void)
113 {
114 struct sa1100irq_state *st = &sa1100irq_state;
115
116 if (st->saved) {
117 ICCR = st->iccr;
118 ICLR = st->iclr;
119
120 ICMR = st->icmr;
121 }
122 }
123
124 static struct syscore_ops sa1100irq_syscore_ops = {
125 .suspend = sa1100irq_suspend,
126 .resume = sa1100irq_resume,
127 };
128
sa1100irq_init_devicefs(void)129 static int __init sa1100irq_init_devicefs(void)
130 {
131 register_syscore_ops(&sa1100irq_syscore_ops);
132 return 0;
133 }
134
135 device_initcall(sa1100irq_init_devicefs);
136
137 static asmlinkage void __exception_irq_entry
sa1100_handle_irq(struct pt_regs * regs)138 sa1100_handle_irq(struct pt_regs *regs)
139 {
140 uint32_t icip, icmr, mask;
141
142 do {
143 icip = (ICIP);
144 icmr = (ICMR);
145 mask = icip & icmr;
146
147 if (mask == 0)
148 break;
149
150 handle_domain_irq(sa1100_normal_irqdomain,
151 ffs(mask) - 1, regs);
152 } while (1);
153 }
154
sa1100_init_irq(void)155 void __init sa1100_init_irq(void)
156 {
157 request_resource(&iomem_resource, &irq_resource);
158
159 /* disable all IRQs */
160 ICMR = 0;
161
162 /* all IRQs are IRQ, not FIQ */
163 ICLR = 0;
164
165 /*
166 * Whatever the doc says, this has to be set for the wait-on-irq
167 * instruction to work... on a SA1100 rev 9 at least.
168 */
169 ICCR = 1;
170
171 sa1100_normal_irqdomain = irq_domain_add_simple(NULL,
172 32, IRQ_GPIO0_SC,
173 &sa1100_normal_irqdomain_ops, NULL);
174
175 set_handle_irq(sa1100_handle_irq);
176
177 sa1100_init_gpio();
178 }
179