hw/gpio/imx_gpio.c

   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
  28 #ifndef DEBUG_IMX_GPIO
  29 #define DEBUG_IMX_GPIO 0
  30 #endif
  31
  32 typedef enum IMXGPIOLevel {
  33     IMX_GPIO_LEVEL_LOW = 0,
  34     IMX_GPIO_LEVEL_HIGH = 1,
  35 } IMXGPIOLevel;
  36
  37 #define DPRINTF(fmt, args...) \
  38     do { \
  39         if (DEBUG_IMX_GPIO) { \
  40             fprintf(stderr, "[%s]%s: " fmt , TYPE_IMX_GPIO, \
  41                                              __func__, ##args); \
  42         } \
  43     } while (0)
  44
  45 static const char *imx_gpio_reg_name(uint32_t reg)
  46 {
  47     switch (reg) {
  48     case DR_ADDR:
  49         return "DR";
  50     case GDIR_ADDR:
  51         return "GDIR";
  52     case PSR_ADDR:
  53         return "PSR";
  54     case ICR1_ADDR:
  55         return "ICR1";
  56     case ICR2_ADDR:
  57         return "ICR2";
  58     case IMR_ADDR:
  59         return "IMR";
  60     case ISR_ADDR:
  61         return "ISR";
  62     case EDGE_SEL_ADDR:
  63         return "EDGE_SEL";
  64     default:
  65         return "[?]";
  66     }
  67 }
  68
  69 static void imx_gpio_update_int(IMXGPIOState *s)
  70 {
  71     if (s->has_upper_pin_irq) {
  72         qemu_set_irq(s->irq[0], (s->isr & s->imr & 0x0000FFFF) ? 1 : 0);
  73         qemu_set_irq(s->irq[1], (s->isr & s->imr & 0xFFFF0000) ? 1 : 0);
  74     } else {
  75         qemu_set_irq(s->irq[0], (s->isr & s->imr) ? 1 : 0);
  76     }
  77 }
  78
  79 static void imx_gpio_set_int_line(IMXGPIOState *s, int line, IMXGPIOLevel level)
  80 {
  81     /* if this signal isn't configured as an input signal, nothing to do */
  82     if (!extract32(s->gdir, line, 1)) {
  83         return;
  84     }
  85
  86     /* When set, EDGE_SEL overrides the ICR config */
  87     if (extract32(s->edge_sel, line, 1)) {
  88         /* we detect interrupt on rising and falling edge */
  89         if (extract32(s->psr, line, 1) != level) {
  90             /* level changed */
  91             s->isr = deposit32(s->isr, line, 1, 1);
  92         }
  93     } else if (extract64(s->icr, 2*line + 1, 1)) {
  94         /* interrupt is edge sensitive */
  95         if (extract32(s->psr, line, 1) != level) {
  96             /* level changed */
  97             if (extract64(s->icr, 2*line, 1) != level) {
  98                 s->isr = deposit32(s->isr, line, 1, 1);
  99             }
 100         }
 101     } else {
 102         /* interrupt is level sensitive */
 103         if (extract64(s->icr, 2*line, 1) == level) {
 104             s->isr = deposit32(s->isr, line, 1, 1);
 105         }
 106     }
 107 }
 108
 109 static void imx_gpio_set(void *opaque, int line, int level)
 110 {
 111     IMXGPIOState *s = IMX_GPIO(opaque);
 112     IMXGPIOLevel imx_level = level ? IMX_GPIO_LEVEL_HIGH : IMX_GPIO_LEVEL_LOW;
 113
 114     imx_gpio_set_int_line(s, line, imx_level);
 115
 116     /* this is an input signal, so set PSR */
 117     s->psr = deposit32(s->psr, line, 1, imx_level);
 118
 119     imx_gpio_update_int(s);
 120 }
 121
 122 static void imx_gpio_set_all_int_lines(IMXGPIOState *s)
 123 {
 124     int i;
 125
 126     for (i = 0; i < IMX_GPIO_PIN_COUNT; i++) {
 127         IMXGPIOLevel imx_level = extract32(s->psr, i, 1);
 128         imx_gpio_set_int_line(s, i, imx_level);
 129     }
 130
 131     imx_gpio_update_int(s);
 132 }
 133
 134 static inline void imx_gpio_set_all_output_lines(IMXGPIOState *s)
 135 {
 136     int i;
 137
 138     for (i = 0; i < IMX_GPIO_PIN_COUNT; i++) {
 139         /*
 140          * if the line is set as output, then forward the line
 141          * level to its user.
 142          */
 143         if (extract32(s->gdir, i, 1) && s->output[i]) {
 144             qemu_set_irq(s->output[i], extract32(s->dr, i, 1));
 145         }
 146     }
 147 }
 148
 149 static uint64_t imx_gpio_read(void *opaque, hwaddr offset, unsigned size)
 150 {
 151     IMXGPIOState *s = IMX_GPIO(opaque);
 152     uint32_t reg_value = 0;
 153
 154     switch (offset) {
 155     case DR_ADDR:
 156         /*
 157          * depending on the "line" configuration, the bit values
 158          * are coming either from DR or PSR
 159          */
 160         reg_value = (s->dr & s->gdir) | (s->psr & ~s->gdir);
 161         break;
 162
 163     case GDIR_ADDR:
 164         reg_value = s->gdir;
 165         break;
 166
 167     case PSR_ADDR:
 168         reg_value = s->psr & ~s->gdir;
 169         break;
 170
 171     case ICR1_ADDR:
 172         reg_value = extract64(s->icr, 0, 32);
 173         break;
 174
 175     case ICR2_ADDR:
 176         reg_value = extract64(s->icr, 32, 32);
 177         break;
 178
 179     case IMR_ADDR:
 180         reg_value = s->imr;
 181         break;
 182
 183     case ISR_ADDR:
 184         reg_value = s->isr;
 185         break;
 186
 187     case EDGE_SEL_ADDR:
 188         if (s->has_edge_sel) {
 189             reg_value = s->edge_sel;
 190         } else {
 191             qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: EDGE_SEL register not "
 192                           "present on this version of GPIO device\n",
 193                           TYPE_IMX_GPIO, __func__);
 194         }
 195         break;
 196
 197     default:
 198         qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
 199                       HWADDR_PRIx "\n", TYPE_IMX_GPIO, __func__, offset);
 200         break;
 201     }
 202
 203     DPRINTF("(%s) = 0x%" PRIx32 "\n", imx_gpio_reg_name(offset), reg_value);
 204
 205     return reg_value;
 206 }
 207
 208 static void imx_gpio_write(void *opaque, hwaddr offset, uint64_t value,
 209                            unsigned size)
 210 {
 211     IMXGPIOState *s = IMX_GPIO(opaque);
 212
 213     DPRINTF("(%s, value = 0x%" PRIx32 ")\n", imx_gpio_reg_name(offset),
 214             (uint32_t)value);
 215
 216     switch (offset) {
 217     case DR_ADDR:
 218         s->dr = value;
 219         imx_gpio_set_all_output_lines(s);
 220         break;
 221
 222     case GDIR_ADDR:
 223         s->gdir = value;
 224         imx_gpio_set_all_output_lines(s);
 225         imx_gpio_set_all_int_lines(s);
 226         break;
 227
 228     case ICR1_ADDR:
 229         s->icr = deposit64(s->icr, 0, 32, value);
 230         imx_gpio_set_all_int_lines(s);
 231         break;
 232
 233     case ICR2_ADDR:
 234         s->icr = deposit64(s->icr, 32, 32, value);
 235         imx_gpio_set_all_int_lines(s);
 236         break;
 237
 238     case IMR_ADDR:
 239         s->imr = value;
 240         imx_gpio_update_int(s);
 241         break;
 242
 243     case ISR_ADDR:
 244         s->isr &= ~value;
 245         imx_gpio_set_all_int_lines(s);
 246         break;
 247
 248     case EDGE_SEL_ADDR:
 249         if (s->has_edge_sel) {
 250             s->edge_sel = value;
 251             imx_gpio_set_all_int_lines(s);
 252         } else {
 253             qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: EDGE_SEL register not "
 254                           "present on this version of GPIO device\n",
 255                           TYPE_IMX_GPIO, __func__);
 256         }
 257         break;
 258
 259     default:
 260         qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
 261                       HWADDR_PRIx "\n", TYPE_IMX_GPIO, __func__, offset);
 262         break;
 263     }
 264
 265     return;
 266 }
 267
 268 static const MemoryRegionOps imx_gpio_ops = {
 269     .read = imx_gpio_read,
 270     .write = imx_gpio_write,
 271     .valid.min_access_size = 4,
 272     .valid.max_access_size = 4,
 273     .endianness = DEVICE_NATIVE_ENDIAN,
 274 };
 275
 276 static const VMStateDescription vmstate_imx_gpio = {
 277     .name = TYPE_IMX_GPIO,
 278     .version_id = 1,
 279     .minimum_version_id = 1,
 280     .fields = (const VMStateField[]) {
 281         VMSTATE_UINT32(dr, IMXGPIOState),
 282         VMSTATE_UINT32(gdir, IMXGPIOState),
 283         VMSTATE_UINT32(psr, IMXGPIOState),
 284         VMSTATE_UINT64(icr, IMXGPIOState),
 285         VMSTATE_UINT32(imr, IMXGPIOState),
 286         VMSTATE_UINT32(isr, IMXGPIOState),
 287         VMSTATE_BOOL(has_edge_sel, IMXGPIOState),
 288         VMSTATE_UINT32(edge_sel, IMXGPIOState),
 289         VMSTATE_END_OF_LIST()
 290     }
 291 };
 292
 293 static Property imx_gpio_properties[] = {
 294     DEFINE_PROP_BOOL("has-edge-sel", IMXGPIOState, has_edge_sel, true),
 295     DEFINE_PROP_BOOL("has-upper-pin-irq", IMXGPIOState, has_upper_pin_irq,
 296                      false),
 297     DEFINE_PROP_END_OF_LIST(),
 298 };
 299
 300 static void imx_gpio_reset(DeviceState *dev)
 301 {
 302     IMXGPIOState *s = IMX_GPIO(dev);
 303
 304     s->dr       = 0;
 305     s->gdir     = 0;
 306     s->psr      = 0;
 307     s->icr      = 0;
 308     s->imr      = 0;
 309     s->isr      = 0;
 310     s->edge_sel = 0;
 311
 312     imx_gpio_set_all_output_lines(s);
 313     imx_gpio_update_int(s);
 314 }
 315
 316 static void imx_gpio_realize(DeviceState *dev, Error **errp)
 317 {
 318     IMXGPIOState *s = IMX_GPIO(dev);
 319
 320     memory_region_init_io(&s->iomem, OBJECT(s), &imx_gpio_ops, s,
 321                           TYPE_IMX_GPIO, IMX_GPIO_MEM_SIZE);
 322
 323     qdev_init_gpio_in(DEVICE(s), imx_gpio_set, IMX_GPIO_PIN_COUNT);
 324     qdev_init_gpio_out(DEVICE(s), s->output, IMX_GPIO_PIN_COUNT);
 325
 326     sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq[0]);
 327     sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq[1]);
 328     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem);
 329 }
 330
 331 static void imx_gpio_class_init(ObjectClass *klass, void *data)
 332 {
 333     DeviceClass *dc = DEVICE_CLASS(klass);
 334
 335     dc->realize = imx_gpio_realize;
 336     device_class_set_legacy_reset(dc, imx_gpio_reset);
 337     device_class_set_props(dc, imx_gpio_properties);
 338     dc->vmsd = &vmstate_imx_gpio;
 339     dc->desc = "i.MX GPIO controller";
 340 }
 341
 342 static const TypeInfo imx_gpio_info = {
 343     .name = TYPE_IMX_GPIO,
 344     .parent = TYPE_SYS_BUS_DEVICE,
 345     .instance_size = sizeof(IMXGPIOState),
 346     .class_init = imx_gpio_class_init,
 347 };
 348
 349 static void imx_gpio_register_types(void)
 350 {
 351     type_register_static(&imx_gpio_info);
 352 }
 353
 354 type_init(imx_gpio_register_types)