xref: /openbmc/qemu/hw/intc/allwinner-a10-pic.c (revision bd2a8884)
1 /*
2  * Allwinner A10 interrupt controller device emulation
3  *
4  * Copyright (C) 2013 Li Guang
5  * Written by Li Guang <lig.fnst@cn.fujitsu.com>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License as published by the
9  * Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful, but WITHOUT
13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15  * for more details.
16  */
17 
18 #include "hw/sysbus.h"
19 #include "hw/devices.h"
20 #include "sysemu/sysemu.h"
21 #include "hw/intc/allwinner-a10-pic.h"
22 
23 static void aw_a10_pic_update(AwA10PICState *s)
24 {
25     uint8_t i;
26     int irq = 0, fiq = 0, zeroes;
27 
28     s->vector = 0;
29 
30     for (i = 0; i < AW_A10_PIC_REG_NUM; i++) {
31         irq |= s->irq_pending[i] & ~s->mask[i];
32         fiq |= s->select[i] & s->irq_pending[i] & ~s->mask[i];
33 
34         if (!s->vector) {
35             zeroes = ctz32(s->irq_pending[i] & ~s->mask[i]);
36             if (zeroes != 32) {
37                 s->vector = (i * 32 + zeroes) * 4;
38             }
39         }
40     }
41 
42     qemu_set_irq(s->parent_irq, !!irq);
43     qemu_set_irq(s->parent_fiq, !!fiq);
44 }
45 
46 static void aw_a10_pic_set_irq(void *opaque, int irq, int level)
47 {
48     AwA10PICState *s = opaque;
49 
50     if (level) {
51         set_bit(irq % 32, (void *)&s->irq_pending[irq / 32]);
52     } else {
53         clear_bit(irq % 32, (void *)&s->irq_pending[irq / 32]);
54     }
55     aw_a10_pic_update(s);
56 }
57 
58 static uint64_t aw_a10_pic_read(void *opaque, hwaddr offset, unsigned size)
59 {
60     AwA10PICState *s = opaque;
61     uint8_t index = (offset & 0xc) / 4;
62 
63     switch (offset) {
64     case AW_A10_PIC_VECTOR:
65         return s->vector;
66     case AW_A10_PIC_BASE_ADDR:
67         return s->base_addr;
68     case AW_A10_PIC_PROTECT:
69         return s->protect;
70     case AW_A10_PIC_NMI:
71         return s->nmi;
72     case AW_A10_PIC_IRQ_PENDING ... AW_A10_PIC_IRQ_PENDING + 8:
73         return s->irq_pending[index];
74     case AW_A10_PIC_FIQ_PENDING ... AW_A10_PIC_FIQ_PENDING + 8:
75         return s->fiq_pending[index];
76     case AW_A10_PIC_SELECT ... AW_A10_PIC_SELECT + 8:
77         return s->select[index];
78     case AW_A10_PIC_ENABLE ... AW_A10_PIC_ENABLE + 8:
79         return s->enable[index];
80     case AW_A10_PIC_MASK ... AW_A10_PIC_MASK + 8:
81         return s->mask[index];
82     default:
83         qemu_log_mask(LOG_GUEST_ERROR,
84                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
85         break;
86     }
87 
88     return 0;
89 }
90 
91 static void aw_a10_pic_write(void *opaque, hwaddr offset, uint64_t value,
92                              unsigned size)
93 {
94     AwA10PICState *s = opaque;
95     uint8_t index = (offset & 0xc) / 4;
96 
97     switch (offset) {
98     case AW_A10_PIC_BASE_ADDR:
99         s->base_addr = value & ~0x3;
100         break;
101     case AW_A10_PIC_PROTECT:
102         s->protect = value;
103         break;
104     case AW_A10_PIC_NMI:
105         s->nmi = value;
106         break;
107     case AW_A10_PIC_IRQ_PENDING ... AW_A10_PIC_IRQ_PENDING + 8:
108         /*
109          * The register is read-only; nevertheless, Linux (including
110          * the version originally shipped by Allwinner) pretends to
111          * write to the register. Just ignore it.
112          */
113         break;
114     case AW_A10_PIC_FIQ_PENDING ... AW_A10_PIC_FIQ_PENDING + 8:
115         s->fiq_pending[index] &= ~value;
116         break;
117     case AW_A10_PIC_SELECT ... AW_A10_PIC_SELECT + 8:
118         s->select[index] = value;
119         break;
120     case AW_A10_PIC_ENABLE ... AW_A10_PIC_ENABLE + 8:
121         s->enable[index] = value;
122         break;
123     case AW_A10_PIC_MASK ... AW_A10_PIC_MASK + 8:
124         s->mask[index] = value;
125         break;
126     default:
127         qemu_log_mask(LOG_GUEST_ERROR,
128                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
129         break;
130     }
131 
132     aw_a10_pic_update(s);
133 }
134 
135 static const MemoryRegionOps aw_a10_pic_ops = {
136     .read = aw_a10_pic_read,
137     .write = aw_a10_pic_write,
138     .endianness = DEVICE_NATIVE_ENDIAN,
139 };
140 
141 static const VMStateDescription vmstate_aw_a10_pic = {
142     .name = "a10.pic",
143     .version_id = 1,
144     .minimum_version_id = 1,
145     .fields = (VMStateField[]) {
146         VMSTATE_UINT32(vector, AwA10PICState),
147         VMSTATE_UINT32(base_addr, AwA10PICState),
148         VMSTATE_UINT32(protect, AwA10PICState),
149         VMSTATE_UINT32(nmi, AwA10PICState),
150         VMSTATE_UINT32_ARRAY(irq_pending, AwA10PICState, AW_A10_PIC_REG_NUM),
151         VMSTATE_UINT32_ARRAY(fiq_pending, AwA10PICState, AW_A10_PIC_REG_NUM),
152         VMSTATE_UINT32_ARRAY(enable, AwA10PICState, AW_A10_PIC_REG_NUM),
153         VMSTATE_UINT32_ARRAY(select, AwA10PICState, AW_A10_PIC_REG_NUM),
154         VMSTATE_UINT32_ARRAY(mask, AwA10PICState, AW_A10_PIC_REG_NUM),
155         VMSTATE_END_OF_LIST()
156     }
157 };
158 
159 static void aw_a10_pic_init(Object *obj)
160 {
161     AwA10PICState *s = AW_A10_PIC(obj);
162     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
163 
164      qdev_init_gpio_in(DEVICE(dev), aw_a10_pic_set_irq, AW_A10_PIC_INT_NR);
165      sysbus_init_irq(dev, &s->parent_irq);
166      sysbus_init_irq(dev, &s->parent_fiq);
167      memory_region_init_io(&s->iomem, OBJECT(s), &aw_a10_pic_ops, s,
168                            TYPE_AW_A10_PIC, 0x400);
169      sysbus_init_mmio(dev, &s->iomem);
170 }
171 
172 static void aw_a10_pic_reset(DeviceState *d)
173 {
174     AwA10PICState *s = AW_A10_PIC(d);
175     uint8_t i;
176 
177     s->base_addr = 0;
178     s->protect = 0;
179     s->nmi = 0;
180     s->vector = 0;
181     for (i = 0; i < AW_A10_PIC_REG_NUM; i++) {
182         s->irq_pending[i] = 0;
183         s->fiq_pending[i] = 0;
184         s->select[i] = 0;
185         s->enable[i] = 0;
186         s->mask[i] = 0;
187     }
188 }
189 
190 static void aw_a10_pic_class_init(ObjectClass *klass, void *data)
191 {
192     DeviceClass *dc = DEVICE_CLASS(klass);
193 
194     dc->reset = aw_a10_pic_reset;
195     dc->desc = "allwinner a10 pic";
196     dc->vmsd = &vmstate_aw_a10_pic;
197  }
198 
199 static const TypeInfo aw_a10_pic_info = {
200     .name = TYPE_AW_A10_PIC,
201     .parent = TYPE_SYS_BUS_DEVICE,
202     .instance_size = sizeof(AwA10PICState),
203     .instance_init = aw_a10_pic_init,
204     .class_init = aw_a10_pic_class_init,
205 };
206 
207 static void aw_a10_register_types(void)
208 {
209     type_register_static(&aw_a10_pic_info);
210 }
211 
212 type_init(aw_a10_register_types);
213