Merge tag 'v3.15-rc1' into perf/urgent
[sfrench/cifs-2.6.git] / arch / arm / mach-footbridge / isa-irq.c
1 /*
2  *  linux/arch/arm/mach-footbridge/irq.c
3  *
4  *  Copyright (C) 1996-2000 Russell King
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  *  Changelog:
11  *   22-Aug-1998 RMK    Restructured IRQ routines
12  *   03-Sep-1998 PJB    Merged CATS support
13  *   20-Jan-1998 RMK    Started merge of EBSA286, CATS and NetWinder
14  *   26-Jan-1999 PJB    Don't use IACK on CATS
15  *   16-Mar-1999 RMK    Added autodetect of ISA PICs
16  */
17 #include <linux/ioport.h>
18 #include <linux/interrupt.h>
19 #include <linux/list.h>
20 #include <linux/init.h>
21 #include <linux/io.h>
22 #include <linux/spinlock.h>
23
24 #include <asm/mach/irq.h>
25
26 #include <mach/hardware.h>
27 #include <asm/hardware/dec21285.h>
28 #include <asm/irq.h>
29 #include <asm/mach-types.h>
30
31 #include "common.h"
32
33 static void isa_mask_pic_lo_irq(struct irq_data *d)
34 {
35         unsigned int mask = 1 << (d->irq & 7);
36
37         outb(inb(PIC_MASK_LO) | mask, PIC_MASK_LO);
38 }
39
40 static void isa_ack_pic_lo_irq(struct irq_data *d)
41 {
42         unsigned int mask = 1 << (d->irq & 7);
43
44         outb(inb(PIC_MASK_LO) | mask, PIC_MASK_LO);
45         outb(0x20, PIC_LO);
46 }
47
48 static void isa_unmask_pic_lo_irq(struct irq_data *d)
49 {
50         unsigned int mask = 1 << (d->irq & 7);
51
52         outb(inb(PIC_MASK_LO) & ~mask, PIC_MASK_LO);
53 }
54
55 static struct irq_chip isa_lo_chip = {
56         .irq_ack        = isa_ack_pic_lo_irq,
57         .irq_mask       = isa_mask_pic_lo_irq,
58         .irq_unmask     = isa_unmask_pic_lo_irq,
59 };
60
61 static void isa_mask_pic_hi_irq(struct irq_data *d)
62 {
63         unsigned int mask = 1 << (d->irq & 7);
64
65         outb(inb(PIC_MASK_HI) | mask, PIC_MASK_HI);
66 }
67
68 static void isa_ack_pic_hi_irq(struct irq_data *d)
69 {
70         unsigned int mask = 1 << (d->irq & 7);
71
72         outb(inb(PIC_MASK_HI) | mask, PIC_MASK_HI);
73         outb(0x62, PIC_LO);
74         outb(0x20, PIC_HI);
75 }
76
77 static void isa_unmask_pic_hi_irq(struct irq_data *d)
78 {
79         unsigned int mask = 1 << (d->irq & 7);
80
81         outb(inb(PIC_MASK_HI) & ~mask, PIC_MASK_HI);
82 }
83
84 static struct irq_chip isa_hi_chip = {
85         .irq_ack        = isa_ack_pic_hi_irq,
86         .irq_mask       = isa_mask_pic_hi_irq,
87         .irq_unmask     = isa_unmask_pic_hi_irq,
88 };
89
90 static void
91 isa_irq_handler(unsigned int irq, struct irq_desc *desc)
92 {
93         unsigned int isa_irq = *(unsigned char *)PCIIACK_BASE;
94
95         if (isa_irq < _ISA_IRQ(0) || isa_irq >= _ISA_IRQ(16)) {
96                 do_bad_IRQ(isa_irq, desc);
97                 return;
98         }
99
100         generic_handle_irq(isa_irq);
101 }
102
103 static struct irqaction irq_cascade = {
104         .handler = no_action,
105         .name = "cascade",
106 };
107
108 static struct resource pic1_resource = {
109         .name   = "pic1",
110         .start  = 0x20,
111         .end    = 0x3f,
112 };
113
114 static struct resource pic2_resource = {
115         .name   = "pic2",
116         .start  = 0xa0,
117         .end    = 0xbf,
118 };
119
120 void __init isa_init_irq(unsigned int host_irq)
121 {
122         unsigned int irq;
123
124         /*
125          * Setup, and then probe for an ISA PIC
126          * If the PIC is not there, then we
127          * ignore the PIC.
128          */
129         outb(0x11, PIC_LO);
130         outb(_ISA_IRQ(0), PIC_MASK_LO); /* IRQ number           */
131         outb(0x04, PIC_MASK_LO);        /* Slave on Ch2         */
132         outb(0x01, PIC_MASK_LO);        /* x86                  */
133         outb(0xf5, PIC_MASK_LO);        /* pattern: 11110101    */
134
135         outb(0x11, PIC_HI);
136         outb(_ISA_IRQ(8), PIC_MASK_HI); /* IRQ number           */
137         outb(0x02, PIC_MASK_HI);        /* Slave on Ch1         */
138         outb(0x01, PIC_MASK_HI);        /* x86                  */
139         outb(0xfa, PIC_MASK_HI);        /* pattern: 11111010    */
140
141         outb(0x0b, PIC_LO);
142         outb(0x0b, PIC_HI);
143
144         if (inb(PIC_MASK_LO) == 0xf5 && inb(PIC_MASK_HI) == 0xfa) {
145                 outb(0xff, PIC_MASK_LO);/* mask all IRQs        */
146                 outb(0xff, PIC_MASK_HI);/* mask all IRQs        */
147         } else {
148                 printk(KERN_INFO "IRQ: ISA PIC not found\n");
149                 host_irq = (unsigned int)-1;
150         }
151
152         if (host_irq != (unsigned int)-1) {
153                 for (irq = _ISA_IRQ(0); irq < _ISA_IRQ(8); irq++) {
154                         irq_set_chip_and_handler(irq, &isa_lo_chip,
155                                                  handle_level_irq);
156                         set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
157                 }
158
159                 for (irq = _ISA_IRQ(8); irq < _ISA_IRQ(16); irq++) {
160                         irq_set_chip_and_handler(irq, &isa_hi_chip,
161                                                  handle_level_irq);
162                         set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
163                 }
164
165                 request_resource(&ioport_resource, &pic1_resource);
166                 request_resource(&ioport_resource, &pic2_resource);
167                 setup_irq(IRQ_ISA_CASCADE, &irq_cascade);
168
169                 irq_set_chained_handler(host_irq, isa_irq_handler);
170
171                 /*
172                  * On the NetWinder, don't automatically
173                  * enable ISA IRQ11 when it is requested.
174                  * There appears to be a missing pull-up
175                  * resistor on this line.
176                  */
177                 if (machine_is_netwinder())
178                         set_irq_flags(_ISA_IRQ(11), IRQF_VALID |
179                                       IRQF_PROBE | IRQF_NOAUTOEN);
180         }
181 }
182
183