xref: /qemu/hw/gpio/imx_gpio.c (revision 70ce076fa6dff60585c229a4b641b13e64bf03cf)
1 /*
2  * i.MX processors GPIO emulation.
3  *
4  * Copyright (C) 2015 Jean-Christophe Dubois <jcd@tribudubois.net>
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation; either version 2 or
9  * (at your option) version 3 of the License.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License along
17  * with this program; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "hw/gpio/imx_gpio.h"
22 #include "hw/irq.h"
23 #include "hw/qdev-properties.h"
24 #include "migration/vmstate.h"
25 #include "qemu/log.h"
26 #include "qemu/module.h"
27 #include "trace.h"
28 
29 #ifndef DEBUG_IMX_GPIO
30 #define DEBUG_IMX_GPIO 0
31 #endif
32 
33 typedef enum IMXGPIOLevel {
34     IMX_GPIO_LEVEL_LOW = 0,
35     IMX_GPIO_LEVEL_HIGH = 1,
36 } IMXGPIOLevel;
37 
38 static const char *imx_gpio_reg_name(uint32_t reg)
39 {
40     switch (reg) {
41     case DR_ADDR:
42         return "DR";
43     case GDIR_ADDR:
44         return "GDIR";
45     case PSR_ADDR:
46         return "PSR";
47     case ICR1_ADDR:
48         return "ICR1";
49     case ICR2_ADDR:
50         return "ICR2";
51     case IMR_ADDR:
52         return "IMR";
53     case ISR_ADDR:
54         return "ISR";
55     case EDGE_SEL_ADDR:
56         return "EDGE_SEL";
57     default:
58         return "[?]";
59     }
60 }
61 
62 static void imx_gpio_update_int(IMXGPIOState *s)
63 {
64     if (s->has_upper_pin_irq) {
65         qemu_set_irq(s->irq[0], (s->isr & s->imr & 0x0000FFFF) ? 1 : 0);
66         qemu_set_irq(s->irq[1], (s->isr & s->imr & 0xFFFF0000) ? 1 : 0);
67     } else {
68         qemu_set_irq(s->irq[0], (s->isr & s->imr) ? 1 : 0);
69     }
70 }
71 
72 static void imx_gpio_set_int_line(IMXGPIOState *s, int line, IMXGPIOLevel level)
73 {
74     /* if this signal isn't configured as an input signal, nothing to do */
75     if (!extract32(s->gdir, line, 1)) {
76         return;
77     }
78 
79     /* When set, EDGE_SEL overrides the ICR config */
80     if (extract32(s->edge_sel, line, 1)) {
81         /* we detect interrupt on rising and falling edge */
82         if (extract32(s->psr, line, 1) != level) {
83             /* level changed */
84             s->isr = deposit32(s->isr, line, 1, 1);
85         }
86     } else if (extract64(s->icr, 2*line + 1, 1)) {
87         /* interrupt is edge sensitive */
88         if (extract32(s->psr, line, 1) != level) {
89             /* level changed */
90             if (extract64(s->icr, 2*line, 1) != level) {
91                 s->isr = deposit32(s->isr, line, 1, 1);
92             }
93         }
94     } else {
95         /* interrupt is level sensitive */
96         if (extract64(s->icr, 2*line, 1) == level) {
97             s->isr = deposit32(s->isr, line, 1, 1);
98         }
99     }
100 }
101 
102 static void imx_gpio_set(void *opaque, int line, int level)
103 {
104     IMXGPIOState *s = IMX_GPIO(opaque);
105     IMXGPIOLevel imx_level = level ? IMX_GPIO_LEVEL_HIGH : IMX_GPIO_LEVEL_LOW;
106 
107     trace_imx_gpio_set(DEVICE(s)->canonical_path, line, imx_level);
108 
109     imx_gpio_set_int_line(s, line, imx_level);
110 
111     /* this is an input signal, so set PSR */
112     s->psr = deposit32(s->psr, line, 1, imx_level);
113 
114     imx_gpio_update_int(s);
115 }
116 
117 static void imx_gpio_set_all_int_lines(IMXGPIOState *s)
118 {
119     int i;
120 
121     for (i = 0; i < IMX_GPIO_PIN_COUNT; i++) {
122         IMXGPIOLevel imx_level = extract32(s->psr, i, 1);
123         imx_gpio_set_int_line(s, i, imx_level);
124     }
125 
126     imx_gpio_update_int(s);
127 }
128 
129 static inline void imx_gpio_set_all_output_lines(IMXGPIOState *s)
130 {
131     int i;
132 
133     for (i = 0; i < IMX_GPIO_PIN_COUNT; i++) {
134         /*
135          * if the line is set as output, then forward the line
136          * level to its user.
137          */
138         if (extract32(s->gdir, i, 1) && s->output[i]) {
139             qemu_set_irq(s->output[i], extract32(s->dr, i, 1));
140         }
141     }
142 }
143 
144 static uint64_t imx_gpio_read(void *opaque, hwaddr offset, unsigned size)
145 {
146     IMXGPIOState *s = IMX_GPIO(opaque);
147     uint32_t reg_value = 0;
148 
149     switch (offset) {
150     case DR_ADDR:
151         /*
152          * depending on the "line" configuration, the bit values
153          * are coming either from DR or PSR
154          */
155         reg_value = (s->dr & s->gdir) | (s->psr & ~s->gdir);
156         break;
157 
158     case GDIR_ADDR:
159         reg_value = s->gdir;
160         break;
161 
162     case PSR_ADDR:
163         reg_value = s->psr & ~s->gdir;
164         break;
165 
166     case ICR1_ADDR:
167         reg_value = extract64(s->icr, 0, 32);
168         break;
169 
170     case ICR2_ADDR:
171         reg_value = extract64(s->icr, 32, 32);
172         break;
173 
174     case IMR_ADDR:
175         reg_value = s->imr;
176         break;
177 
178     case ISR_ADDR:
179         reg_value = s->isr;
180         break;
181 
182     case EDGE_SEL_ADDR:
183         if (s->has_edge_sel) {
184             reg_value = s->edge_sel;
185         } else {
186             qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: EDGE_SEL register not "
187                           "present on this version of GPIO device\n",
188                           TYPE_IMX_GPIO, __func__);
189         }
190         break;
191 
192     default:
193         qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
194                       HWADDR_PRIx "\n", TYPE_IMX_GPIO, __func__, offset);
195         break;
196     }
197 
198     trace_imx_gpio_read(DEVICE(s)->canonical_path, imx_gpio_reg_name(offset),
199                         reg_value);
200 
201     return reg_value;
202 }
203 
204 static void imx_gpio_write(void *opaque, hwaddr offset, uint64_t value,
205                            unsigned size)
206 {
207     IMXGPIOState *s = IMX_GPIO(opaque);
208 
209     trace_imx_gpio_write(DEVICE(s)->canonical_path, imx_gpio_reg_name(offset),
210                          value);
211 
212     switch (offset) {
213     case DR_ADDR:
214         s->dr = value;
215         imx_gpio_set_all_output_lines(s);
216         break;
217 
218     case GDIR_ADDR:
219         s->gdir = value;
220         imx_gpio_set_all_output_lines(s);
221         imx_gpio_set_all_int_lines(s);
222         break;
223 
224     case ICR1_ADDR:
225         s->icr = deposit64(s->icr, 0, 32, value);
226         imx_gpio_set_all_int_lines(s);
227         break;
228 
229     case ICR2_ADDR:
230         s->icr = deposit64(s->icr, 32, 32, value);
231         imx_gpio_set_all_int_lines(s);
232         break;
233 
234     case IMR_ADDR:
235         s->imr = value;
236         imx_gpio_update_int(s);
237         break;
238 
239     case ISR_ADDR:
240         s->isr &= ~value;
241         imx_gpio_set_all_int_lines(s);
242         break;
243 
244     case EDGE_SEL_ADDR:
245         if (s->has_edge_sel) {
246             s->edge_sel = value;
247             imx_gpio_set_all_int_lines(s);
248         } else {
249             qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: EDGE_SEL register not "
250                           "present on this version of GPIO device\n",
251                           TYPE_IMX_GPIO, __func__);
252         }
253         break;
254 
255     default:
256         qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
257                       HWADDR_PRIx "\n", TYPE_IMX_GPIO, __func__, offset);
258         break;
259     }
260 
261     return;
262 }
263 
264 static const MemoryRegionOps imx_gpio_ops = {
265     .read = imx_gpio_read,
266     .write = imx_gpio_write,
267     .valid.min_access_size = 4,
268     .valid.max_access_size = 4,
269     .endianness = DEVICE_NATIVE_ENDIAN,
270 };
271 
272 static const VMStateDescription vmstate_imx_gpio = {
273     .name = TYPE_IMX_GPIO,
274     .version_id = 1,
275     .minimum_version_id = 1,
276     .fields = (const VMStateField[]) {
277         VMSTATE_UINT32(dr, IMXGPIOState),
278         VMSTATE_UINT32(gdir, IMXGPIOState),
279         VMSTATE_UINT32(psr, IMXGPIOState),
280         VMSTATE_UINT64(icr, IMXGPIOState),
281         VMSTATE_UINT32(imr, IMXGPIOState),
282         VMSTATE_UINT32(isr, IMXGPIOState),
283         VMSTATE_BOOL(has_edge_sel, IMXGPIOState),
284         VMSTATE_UINT32(edge_sel, IMXGPIOState),
285         VMSTATE_END_OF_LIST()
286     }
287 };
288 
289 static const Property imx_gpio_properties[] = {
290     DEFINE_PROP_BOOL("has-edge-sel", IMXGPIOState, has_edge_sel, true),
291     DEFINE_PROP_BOOL("has-upper-pin-irq", IMXGPIOState, has_upper_pin_irq,
292                      false),
293 };
294 
295 static void imx_gpio_reset(DeviceState *dev)
296 {
297     IMXGPIOState *s = IMX_GPIO(dev);
298 
299     s->dr       = 0;
300     s->gdir     = 0;
301     s->psr      = 0;
302     s->icr      = 0;
303     s->imr      = 0;
304     s->isr      = 0;
305     s->edge_sel = 0;
306 
307     imx_gpio_set_all_output_lines(s);
308     imx_gpio_update_int(s);
309 }
310 
311 static void imx_gpio_realize(DeviceState *dev, Error **errp)
312 {
313     IMXGPIOState *s = IMX_GPIO(dev);
314 
315     memory_region_init_io(&s->iomem, OBJECT(s), &imx_gpio_ops, s,
316                           TYPE_IMX_GPIO, IMX_GPIO_MEM_SIZE);
317 
318     qdev_init_gpio_in(DEVICE(s), imx_gpio_set, IMX_GPIO_PIN_COUNT);
319     qdev_init_gpio_out(DEVICE(s), s->output, IMX_GPIO_PIN_COUNT);
320 
321     sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq[0]);
322     sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq[1]);
323     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem);
324 }
325 
326 static void imx_gpio_class_init(ObjectClass *klass, void *data)
327 {
328     DeviceClass *dc = DEVICE_CLASS(klass);
329 
330     dc->realize = imx_gpio_realize;
331     device_class_set_legacy_reset(dc, imx_gpio_reset);
332     device_class_set_props(dc, imx_gpio_properties);
333     dc->vmsd = &vmstate_imx_gpio;
334     dc->desc = "i.MX GPIO controller";
335 }
336 
337 static const TypeInfo imx_gpio_info = {
338     .name = TYPE_IMX_GPIO,
339     .parent = TYPE_SYS_BUS_DEVICE,
340     .instance_size = sizeof(IMXGPIOState),
341     .class_init = imx_gpio_class_init,
342 };
343 
344 static void imx_gpio_register_types(void)
345 {
346     type_register_static(&imx_gpio_info);
347 }
348 
349 type_init(imx_gpio_register_types)
350