1 /*
2 * GPIO Controller for a lot of Freescale SoCs
3 *
4 * Copyright (C) 2014 Freescale Semiconductor, Inc. All rights reserved.
5 *
6 * Author: Alexander Graf, <agraf@suse.de>
7 *
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * This library 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 GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
20 */
21
22 #include "qemu/osdep.h"
23 #include "hw/irq.h"
24 #include "hw/sysbus.h"
25 #include "migration/vmstate.h"
26 #include "qom/object.h"
27
28 #define TYPE_MPC8XXX_GPIO "mpc8xxx_gpio"
29 OBJECT_DECLARE_SIMPLE_TYPE(MPC8XXXGPIOState, MPC8XXX_GPIO)
30
31 struct MPC8XXXGPIOState {
32 SysBusDevice parent_obj;
33
34 MemoryRegion iomem;
35 qemu_irq irq;
36 qemu_irq out[32];
37
38 uint32_t dir;
39 uint32_t odr;
40 uint32_t dat;
41 uint32_t ier;
42 uint32_t imr;
43 uint32_t icr;
44 };
45
46 static const VMStateDescription vmstate_mpc8xxx_gpio = {
47 .name = "mpc8xxx_gpio",
48 .version_id = 1,
49 .minimum_version_id = 1,
50 .fields = (const VMStateField[]) {
51 VMSTATE_UINT32(dir, MPC8XXXGPIOState),
52 VMSTATE_UINT32(odr, MPC8XXXGPIOState),
53 VMSTATE_UINT32(dat, MPC8XXXGPIOState),
54 VMSTATE_UINT32(ier, MPC8XXXGPIOState),
55 VMSTATE_UINT32(imr, MPC8XXXGPIOState),
56 VMSTATE_UINT32(icr, MPC8XXXGPIOState),
57 VMSTATE_END_OF_LIST()
58 }
59 };
60
mpc8xxx_gpio_update(MPC8XXXGPIOState * s)61 static void mpc8xxx_gpio_update(MPC8XXXGPIOState *s)
62 {
63 qemu_set_irq(s->irq, !!(s->ier & s->imr));
64 }
65
mpc8xxx_gpio_read(void * opaque,hwaddr offset,unsigned size)66 static uint64_t mpc8xxx_gpio_read(void *opaque, hwaddr offset,
67 unsigned size)
68 {
69 MPC8XXXGPIOState *s = (MPC8XXXGPIOState *)opaque;
70
71 if (size != 4) {
72 /* All registers are 32bit */
73 return 0;
74 }
75
76 switch (offset) {
77 case 0x0: /* Direction */
78 return s->dir;
79 case 0x4: /* Open Drain */
80 return s->odr;
81 case 0x8: /* Data */
82 return s->dat;
83 case 0xC: /* Interrupt Event */
84 return s->ier;
85 case 0x10: /* Interrupt Mask */
86 return s->imr;
87 case 0x14: /* Interrupt Control */
88 return s->icr;
89 default:
90 return 0;
91 }
92 }
93
mpc8xxx_write_data(MPC8XXXGPIOState * s,uint32_t new_data)94 static void mpc8xxx_write_data(MPC8XXXGPIOState *s, uint32_t new_data)
95 {
96 uint32_t old_data = s->dat;
97 uint32_t diff = old_data ^ new_data;
98 int i;
99
100 for (i = 0; i < 32; i++) {
101 uint32_t mask = 0x80000000 >> i;
102 if (!(diff & mask)) {
103 continue;
104 }
105
106 if (s->dir & mask) {
107 /* Output */
108 qemu_set_irq(s->out[i], (new_data & mask) != 0);
109 }
110 }
111
112 s->dat = new_data;
113 }
114
mpc8xxx_gpio_write(void * opaque,hwaddr offset,uint64_t value,unsigned size)115 static void mpc8xxx_gpio_write(void *opaque, hwaddr offset,
116 uint64_t value, unsigned size)
117 {
118 MPC8XXXGPIOState *s = (MPC8XXXGPIOState *)opaque;
119
120 if (size != 4) {
121 /* All registers are 32bit */
122 return;
123 }
124
125 switch (offset) {
126 case 0x0: /* Direction */
127 s->dir = value;
128 break;
129 case 0x4: /* Open Drain */
130 s->odr = value;
131 break;
132 case 0x8: /* Data */
133 mpc8xxx_write_data(s, value);
134 break;
135 case 0xC: /* Interrupt Event */
136 s->ier &= ~value;
137 break;
138 case 0x10: /* Interrupt Mask */
139 s->imr = value;
140 break;
141 case 0x14: /* Interrupt Control */
142 s->icr = value;
143 break;
144 }
145
146 mpc8xxx_gpio_update(s);
147 }
148
mpc8xxx_gpio_reset(DeviceState * dev)149 static void mpc8xxx_gpio_reset(DeviceState *dev)
150 {
151 MPC8XXXGPIOState *s = MPC8XXX_GPIO(dev);
152
153 s->dir = 0;
154 s->odr = 0;
155 s->dat = 0;
156 s->ier = 0;
157 s->imr = 0;
158 s->icr = 0;
159 }
160
mpc8xxx_gpio_set_irq(void * opaque,int irq,int level)161 static void mpc8xxx_gpio_set_irq(void * opaque, int irq, int level)
162 {
163 MPC8XXXGPIOState *s = (MPC8XXXGPIOState *)opaque;
164 uint32_t mask;
165
166 mask = 0x80000000 >> irq;
167 if ((s->dir & mask) == 0) {
168 uint32_t old_value = s->dat & mask;
169
170 s->dat &= ~mask;
171 if (level)
172 s->dat |= mask;
173
174 if (!(s->icr & irq) || (old_value && !level)) {
175 s->ier |= mask;
176 }
177
178 mpc8xxx_gpio_update(s);
179 }
180 }
181
182 static const MemoryRegionOps mpc8xxx_gpio_ops = {
183 .read = mpc8xxx_gpio_read,
184 .write = mpc8xxx_gpio_write,
185 .endianness = DEVICE_BIG_ENDIAN,
186 };
187
mpc8xxx_gpio_initfn(Object * obj)188 static void mpc8xxx_gpio_initfn(Object *obj)
189 {
190 DeviceState *dev = DEVICE(obj);
191 MPC8XXXGPIOState *s = MPC8XXX_GPIO(obj);
192 SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
193
194 memory_region_init_io(&s->iomem, obj, &mpc8xxx_gpio_ops,
195 s, "mpc8xxx_gpio", 0x1000);
196 sysbus_init_mmio(sbd, &s->iomem);
197 sysbus_init_irq(sbd, &s->irq);
198 qdev_init_gpio_in(dev, mpc8xxx_gpio_set_irq, 32);
199 qdev_init_gpio_out(dev, s->out, 32);
200 }
201
mpc8xxx_gpio_class_init(ObjectClass * klass,void * data)202 static void mpc8xxx_gpio_class_init(ObjectClass *klass, void *data)
203 {
204 DeviceClass *dc = DEVICE_CLASS(klass);
205
206 dc->vmsd = &vmstate_mpc8xxx_gpio;
207 device_class_set_legacy_reset(dc, mpc8xxx_gpio_reset);
208 }
209
210 static const TypeInfo mpc8xxx_gpio_types[] = {
211 {
212 .name = TYPE_MPC8XXX_GPIO,
213 .parent = TYPE_SYS_BUS_DEVICE,
214 .instance_size = sizeof(MPC8XXXGPIOState),
215 .instance_init = mpc8xxx_gpio_initfn,
216 .class_init = mpc8xxx_gpio_class_init,
217 },
218 };
219
220 DEFINE_TYPES(mpc8xxx_gpio_types)
221