xref: /openbmc/qemu/hw/intc/allwinner-a10-pic.c (revision 9884abee)
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 "qemu/osdep.h"
19 #include "hw/sysbus.h"
20 #include "hw/devices.h"
21 #include "sysemu/sysemu.h"
22 #include "hw/intc/allwinner-a10-pic.h"
23 
24 static void aw_a10_pic_update(AwA10PICState *s)
25 {
26     uint8_t i;
27     int irq = 0, fiq = 0, zeroes;
28 
29     s->vector = 0;
30 
31     for (i = 0; i < AW_A10_PIC_REG_NUM; i++) {
32         irq |= s->irq_pending[i] & ~s->mask[i];
33         fiq |= s->select[i] & s->irq_pending[i] & ~s->mask[i];
34 
35         if (!s->vector) {
36             zeroes = ctz32(s->irq_pending[i] & ~s->mask[i]);
37             if (zeroes != 32) {
38                 s->vector = (i * 32 + zeroes) * 4;
39             }
40         }
41     }
42 
43     qemu_set_irq(s->parent_irq, !!irq);
44     qemu_set_irq(s->parent_fiq, !!fiq);
45 }
46 
47 static void aw_a10_pic_set_irq(void *opaque, int irq, int level)
48 {
49     AwA10PICState *s = opaque;
50 
51     if (level) {
52         set_bit(irq % 32, (void *)&s->irq_pending[irq / 32]);
53     } else {
54         clear_bit(irq % 32, (void *)&s->irq_pending[irq / 32]);
55     }
56     aw_a10_pic_update(s);
57 }
58 
59 static uint64_t aw_a10_pic_read(void *opaque, hwaddr offset, unsigned size)
60 {
61     AwA10PICState *s = opaque;
62     uint8_t index = (offset & 0xc) / 4;
63 
64     switch (offset) {
65     case AW_A10_PIC_VECTOR:
66         return s->vector;
67     case AW_A10_PIC_BASE_ADDR:
68         return s->base_addr;
69     case AW_A10_PIC_PROTECT:
70         return s->protect;
71     case AW_A10_PIC_NMI:
72         return s->nmi;
73     case AW_A10_PIC_IRQ_PENDING ... AW_A10_PIC_IRQ_PENDING + 8:
74         return s->irq_pending[index];
75     case AW_A10_PIC_FIQ_PENDING ... AW_A10_PIC_FIQ_PENDING + 8:
76         return s->fiq_pending[index];
77     case AW_A10_PIC_SELECT ... AW_A10_PIC_SELECT + 8:
78         return s->select[index];
79     case AW_A10_PIC_ENABLE ... AW_A10_PIC_ENABLE + 8:
80         return s->enable[index];
81     case AW_A10_PIC_MASK ... AW_A10_PIC_MASK + 8:
82         return s->mask[index];
83     default:
84         qemu_log_mask(LOG_GUEST_ERROR,
85                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
86         break;
87     }
88 
89     return 0;
90 }
91 
92 static void aw_a10_pic_write(void *opaque, hwaddr offset, uint64_t value,
93                              unsigned size)
94 {
95     AwA10PICState *s = opaque;
96     uint8_t index = (offset & 0xc) / 4;
97 
98     switch (offset) {
99     case AW_A10_PIC_BASE_ADDR:
100         s->base_addr = value & ~0x3;
101         break;
102     case AW_A10_PIC_PROTECT:
103         s->protect = value;
104         break;
105     case AW_A10_PIC_NMI:
106         s->nmi = value;
107         break;
108     case AW_A10_PIC_IRQ_PENDING ... AW_A10_PIC_IRQ_PENDING + 8:
109         /*
110          * The register is read-only; nevertheless, Linux (including
111          * the version originally shipped by Allwinner) pretends to
112          * write to the register. Just ignore it.
113          */
114         break;
115     case AW_A10_PIC_FIQ_PENDING ... AW_A10_PIC_FIQ_PENDING + 8:
116         s->fiq_pending[index] &= ~value;
117         break;
118     case AW_A10_PIC_SELECT ... AW_A10_PIC_SELECT + 8:
119         s->select[index] = value;
120         break;
121     case AW_A10_PIC_ENABLE ... AW_A10_PIC_ENABLE + 8:
122         s->enable[index] = value;
123         break;
124     case AW_A10_PIC_MASK ... AW_A10_PIC_MASK + 8:
125         s->mask[index] = value;
126         break;
127     default:
128         qemu_log_mask(LOG_GUEST_ERROR,
129                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
130         break;
131     }
132 
133     aw_a10_pic_update(s);
134 }
135 
136 static const MemoryRegionOps aw_a10_pic_ops = {
137     .read = aw_a10_pic_read,
138     .write = aw_a10_pic_write,
139     .endianness = DEVICE_NATIVE_ENDIAN,
140 };
141 
142 static const VMStateDescription vmstate_aw_a10_pic = {
143     .name = "a10.pic",
144     .version_id = 1,
145     .minimum_version_id = 1,
146     .fields = (VMStateField[]) {
147         VMSTATE_UINT32(vector, AwA10PICState),
148         VMSTATE_UINT32(base_addr, AwA10PICState),
149         VMSTATE_UINT32(protect, AwA10PICState),
150         VMSTATE_UINT32(nmi, AwA10PICState),
151         VMSTATE_UINT32_ARRAY(irq_pending, AwA10PICState, AW_A10_PIC_REG_NUM),
152         VMSTATE_UINT32_ARRAY(fiq_pending, AwA10PICState, AW_A10_PIC_REG_NUM),
153         VMSTATE_UINT32_ARRAY(enable, AwA10PICState, AW_A10_PIC_REG_NUM),
154         VMSTATE_UINT32_ARRAY(select, AwA10PICState, AW_A10_PIC_REG_NUM),
155         VMSTATE_UINT32_ARRAY(mask, AwA10PICState, AW_A10_PIC_REG_NUM),
156         VMSTATE_END_OF_LIST()
157     }
158 };
159 
160 static void aw_a10_pic_init(Object *obj)
161 {
162     AwA10PICState *s = AW_A10_PIC(obj);
163     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
164 
165      qdev_init_gpio_in(DEVICE(dev), aw_a10_pic_set_irq, AW_A10_PIC_INT_NR);
166      sysbus_init_irq(dev, &s->parent_irq);
167      sysbus_init_irq(dev, &s->parent_fiq);
168      memory_region_init_io(&s->iomem, OBJECT(s), &aw_a10_pic_ops, s,
169                            TYPE_AW_A10_PIC, 0x400);
170      sysbus_init_mmio(dev, &s->iomem);
171 }
172 
173 static void aw_a10_pic_reset(DeviceState *d)
174 {
175     AwA10PICState *s = AW_A10_PIC(d);
176     uint8_t i;
177 
178     s->base_addr = 0;
179     s->protect = 0;
180     s->nmi = 0;
181     s->vector = 0;
182     for (i = 0; i < AW_A10_PIC_REG_NUM; i++) {
183         s->irq_pending[i] = 0;
184         s->fiq_pending[i] = 0;
185         s->select[i] = 0;
186         s->enable[i] = 0;
187         s->mask[i] = 0;
188     }
189 }
190 
191 static void aw_a10_pic_class_init(ObjectClass *klass, void *data)
192 {
193     DeviceClass *dc = DEVICE_CLASS(klass);
194 
195     dc->reset = aw_a10_pic_reset;
196     dc->desc = "allwinner a10 pic";
197     dc->vmsd = &vmstate_aw_a10_pic;
198  }
199 
200 static const TypeInfo aw_a10_pic_info = {
201     .name = TYPE_AW_A10_PIC,
202     .parent = TYPE_SYS_BUS_DEVICE,
203     .instance_size = sizeof(AwA10PICState),
204     .instance_init = aw_a10_pic_init,
205     .class_init = aw_a10_pic_class_init,
206 };
207 
208 static void aw_a10_register_types(void)
209 {
210     type_register_static(&aw_a10_pic_info);
211 }
212 
213 type_init(aw_a10_register_types);
214