Merge branch 'linus' into timers/hpet
[linux-2.6] / arch / arm / mach-at91 / irq.c
1 /*
2  * linux/arch/arm/mach-at91/irq.c
3  *
4  *  Copyright (C) 2004 SAN People
5  *  Copyright (C) 2004 ATMEL
6  *  Copyright (C) Rick Bronson
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 as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21  */
22
23 #include <linux/init.h>
24 #include <linux/module.h>
25 #include <linux/mm.h>
26 #include <linux/types.h>
27
28 #include <asm/hardware.h>
29 #include <asm/irq.h>
30 #include <asm/mach-types.h>
31 #include <asm/setup.h>
32
33 #include <asm/mach/arch.h>
34 #include <asm/mach/irq.h>
35 #include <asm/mach/map.h>
36
37
38 static void at91_aic_mask_irq(unsigned int irq)
39 {
40         /* Disable interrupt on AIC */
41         at91_sys_write(AT91_AIC_IDCR, 1 << irq);
42 }
43
44 static void at91_aic_unmask_irq(unsigned int irq)
45 {
46         /* Enable interrupt on AIC */
47         at91_sys_write(AT91_AIC_IECR, 1 << irq);
48 }
49
50 unsigned int at91_extern_irq;
51
52 #define is_extern_irq(irq) ((1 << (irq)) & at91_extern_irq)
53
54 static int at91_aic_set_type(unsigned irq, unsigned type)
55 {
56         unsigned int smr, srctype;
57
58         switch (type) {
59         case IRQ_TYPE_LEVEL_HIGH:
60                 srctype = AT91_AIC_SRCTYPE_HIGH;
61                 break;
62         case IRQ_TYPE_EDGE_RISING:
63                 srctype = AT91_AIC_SRCTYPE_RISING;
64                 break;
65         case IRQ_TYPE_LEVEL_LOW:
66                 if ((irq == AT91_ID_FIQ) || is_extern_irq(irq))         /* only supported on external interrupts */
67                         srctype = AT91_AIC_SRCTYPE_LOW;
68                 else
69                         return -EINVAL;
70                 break;
71         case IRQ_TYPE_EDGE_FALLING:
72                 if ((irq == AT91_ID_FIQ) || is_extern_irq(irq))         /* only supported on external interrupts */
73                         srctype = AT91_AIC_SRCTYPE_FALLING;
74                 else
75                         return -EINVAL;
76                 break;
77         default:
78                 return -EINVAL;
79         }
80
81         smr = at91_sys_read(AT91_AIC_SMR(irq)) & ~AT91_AIC_SRCTYPE;
82         at91_sys_write(AT91_AIC_SMR(irq), smr | srctype);
83         return 0;
84 }
85
86 #ifdef CONFIG_PM
87
88 static u32 wakeups;
89 static u32 backups;
90
91 static int at91_aic_set_wake(unsigned irq, unsigned value)
92 {
93         if (unlikely(irq >= 32))
94                 return -EINVAL;
95
96         if (value)
97                 wakeups |= (1 << irq);
98         else
99                 wakeups &= ~(1 << irq);
100
101         return 0;
102 }
103
104 void at91_irq_suspend(void)
105 {
106         backups = at91_sys_read(AT91_AIC_IMR);
107         at91_sys_write(AT91_AIC_IDCR, backups);
108         at91_sys_write(AT91_AIC_IECR, wakeups);
109 }
110
111 void at91_irq_resume(void)
112 {
113         at91_sys_write(AT91_AIC_IDCR, wakeups);
114         at91_sys_write(AT91_AIC_IECR, backups);
115 }
116
117 #else
118 #define at91_aic_set_wake       NULL
119 #endif
120
121 static struct irq_chip at91_aic_chip = {
122         .name           = "AIC",
123         .ack            = at91_aic_mask_irq,
124         .mask           = at91_aic_mask_irq,
125         .unmask         = at91_aic_unmask_irq,
126         .set_type       = at91_aic_set_type,
127         .set_wake       = at91_aic_set_wake,
128 };
129
130 /*
131  * Initialize the AIC interrupt controller.
132  */
133 void __init at91_aic_init(unsigned int priority[NR_AIC_IRQS])
134 {
135         unsigned int i;
136
137         /*
138          * The IVR is used by macro get_irqnr_and_base to read and verify.
139          * The irq number is NR_AIC_IRQS when a spurious interrupt has occurred.
140          */
141         for (i = 0; i < NR_AIC_IRQS; i++) {
142                 /* Put irq number in Source Vector Register: */
143                 at91_sys_write(AT91_AIC_SVR(i), i);
144                 /* Active Low interrupt, with the specified priority */
145                 at91_sys_write(AT91_AIC_SMR(i), AT91_AIC_SRCTYPE_LOW | priority[i]);
146
147                 set_irq_chip(i, &at91_aic_chip);
148                 set_irq_handler(i, handle_level_irq);
149                 set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
150
151                 /* Perform 8 End Of Interrupt Command to make sure AIC will not Lock out nIRQ */
152                 if (i < 8)
153                         at91_sys_write(AT91_AIC_EOICR, 0);
154         }
155
156         /*
157          * Spurious Interrupt ID in Spurious Vector Register is NR_AIC_IRQS
158          * When there is no current interrupt, the IRQ Vector Register reads the value stored in AIC_SPU
159          */
160         at91_sys_write(AT91_AIC_SPU, NR_AIC_IRQS);
161
162         /* No debugging in AIC: Debug (Protect) Control Register */
163         at91_sys_write(AT91_AIC_DCR, 0);
164
165         /* Disable and clear all interrupts initially */
166         at91_sys_write(AT91_AIC_IDCR, 0xFFFFFFFF);
167         at91_sys_write(AT91_AIC_ICCR, 0xFFFFFFFF);
168 }