1 /* 2 * Nuvoton NPCM7xx General Purpose Input / Output (GPIO) 3 * 4 * Copyright 2020 Google LLC 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 8 * version 2 as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 */ 15 16 #include "qemu/osdep.h" 17 18 #include "hw/gpio/npcm7xx_gpio.h" 19 #include "hw/irq.h" 20 #include "hw/qdev-properties.h" 21 #include "migration/vmstate.h" 22 #include "qapi/error.h" 23 #include "qemu/log.h" 24 #include "qemu/module.h" 25 #include "qemu/units.h" 26 #include "trace.h" 27 28 /* 32-bit register indices. */ 29 enum NPCM7xxGPIORegister { 30 NPCM7XX_GPIO_TLOCK1, 31 NPCM7XX_GPIO_DIN, 32 NPCM7XX_GPIO_POL, 33 NPCM7XX_GPIO_DOUT, 34 NPCM7XX_GPIO_OE, 35 NPCM7XX_GPIO_OTYP, 36 NPCM7XX_GPIO_MP, 37 NPCM7XX_GPIO_PU, 38 NPCM7XX_GPIO_PD, 39 NPCM7XX_GPIO_DBNC, 40 NPCM7XX_GPIO_EVTYP, 41 NPCM7XX_GPIO_EVBE, 42 NPCM7XX_GPIO_OBL0, 43 NPCM7XX_GPIO_OBL1, 44 NPCM7XX_GPIO_OBL2, 45 NPCM7XX_GPIO_OBL3, 46 NPCM7XX_GPIO_EVEN, 47 NPCM7XX_GPIO_EVENS, 48 NPCM7XX_GPIO_EVENC, 49 NPCM7XX_GPIO_EVST, 50 NPCM7XX_GPIO_SPLCK, 51 NPCM7XX_GPIO_MPLCK, 52 NPCM7XX_GPIO_IEM, 53 NPCM7XX_GPIO_OSRC, 54 NPCM7XX_GPIO_ODSC, 55 NPCM7XX_GPIO_DOS = 0x68 / sizeof(uint32_t), 56 NPCM7XX_GPIO_DOC, 57 NPCM7XX_GPIO_OES, 58 NPCM7XX_GPIO_OEC, 59 NPCM7XX_GPIO_TLOCK2 = 0x7c / sizeof(uint32_t), 60 NPCM7XX_GPIO_REGS_END, 61 }; 62 63 #define NPCM7XX_GPIO_REGS_SIZE (4 * KiB) 64 65 #define NPCM7XX_GPIO_LOCK_MAGIC1 (0xc0defa73) 66 #define NPCM7XX_GPIO_LOCK_MAGIC2 (0xc0de1248) 67 68 static void npcm7xx_gpio_update_events(NPCM7xxGPIOState *s, uint32_t din_diff) 69 { 70 uint32_t din_new = s->regs[NPCM7XX_GPIO_DIN]; 71 72 /* Trigger on high level */ 73 s->regs[NPCM7XX_GPIO_EVST] |= din_new & ~s->regs[NPCM7XX_GPIO_EVTYP]; 74 /* Trigger on both edges */ 75 s->regs[NPCM7XX_GPIO_EVST] |= (din_diff & s->regs[NPCM7XX_GPIO_EVTYP] 76 & s->regs[NPCM7XX_GPIO_EVBE]); 77 /* Trigger on rising edge */ 78 s->regs[NPCM7XX_GPIO_EVST] |= (din_diff & din_new 79 & s->regs[NPCM7XX_GPIO_EVTYP]); 80 81 trace_npcm7xx_gpio_update_events(DEVICE(s)->canonical_path, 82 s->regs[NPCM7XX_GPIO_EVST], 83 s->regs[NPCM7XX_GPIO_EVEN]); 84 qemu_set_irq(s->irq, !!(s->regs[NPCM7XX_GPIO_EVST] 85 & s->regs[NPCM7XX_GPIO_EVEN])); 86 } 87 88 static void npcm7xx_gpio_update_pins(NPCM7xxGPIOState *s, uint32_t diff) 89 { 90 uint32_t drive_en; 91 uint32_t drive_lvl; 92 uint32_t not_driven; 93 uint32_t undefined; 94 uint32_t pin_diff; 95 uint32_t din_old; 96 97 /* Calculate level of each pin driven by GPIO controller. */ 98 drive_lvl = s->regs[NPCM7XX_GPIO_DOUT] ^ s->regs[NPCM7XX_GPIO_POL]; 99 /* If OTYP=1, only drive low (open drain) */ 100 drive_en = s->regs[NPCM7XX_GPIO_OE] & ~(s->regs[NPCM7XX_GPIO_OTYP] 101 & drive_lvl); 102 /* 103 * If a pin is driven to opposite levels by the GPIO controller and the 104 * external driver, the result is undefined. 105 */ 106 undefined = drive_en & s->ext_driven & (drive_lvl ^ s->ext_level); 107 if (undefined) { 108 qemu_log_mask(LOG_GUEST_ERROR, 109 "%s: pins have multiple drivers: 0x%" PRIx32 "\n", 110 DEVICE(s)->canonical_path, undefined); 111 } 112 113 not_driven = ~(drive_en | s->ext_driven); 114 pin_diff = s->pin_level; 115 116 /* Set pins to externally driven level. */ 117 s->pin_level = s->ext_level & s->ext_driven; 118 /* Set internally driven pins, ignoring any conflicts. */ 119 s->pin_level |= drive_lvl & drive_en; 120 /* Pull up undriven pins with internal pull-up enabled. */ 121 s->pin_level |= not_driven & s->regs[NPCM7XX_GPIO_PU]; 122 /* Pins not driven, pulled up or pulled down are undefined */ 123 undefined |= not_driven & ~(s->regs[NPCM7XX_GPIO_PU] 124 | s->regs[NPCM7XX_GPIO_PD]); 125 126 /* If any pins changed state, update the outgoing GPIOs. */ 127 pin_diff ^= s->pin_level; 128 pin_diff |= undefined & diff; 129 if (pin_diff) { 130 int i; 131 132 for (i = 0; i < NPCM7XX_GPIO_NR_PINS; i++) { 133 uint32_t mask = BIT(i); 134 if (pin_diff & mask) { 135 int level = (undefined & mask) ? -1 : !!(s->pin_level & mask); 136 trace_npcm7xx_gpio_set_output(DEVICE(s)->canonical_path, 137 i, level); 138 qemu_set_irq(s->output[i], level); 139 } 140 } 141 } 142 143 /* Calculate new value of DIN after masking and polarity setting. */ 144 din_old = s->regs[NPCM7XX_GPIO_DIN]; 145 s->regs[NPCM7XX_GPIO_DIN] = ((s->pin_level & s->regs[NPCM7XX_GPIO_IEM]) 146 ^ s->regs[NPCM7XX_GPIO_POL]); 147 148 /* See if any new events triggered because of all this. */ 149 npcm7xx_gpio_update_events(s, din_old ^ s->regs[NPCM7XX_GPIO_DIN]); 150 } 151 152 static bool npcm7xx_gpio_is_locked(NPCM7xxGPIOState *s) 153 { 154 return s->regs[NPCM7XX_GPIO_TLOCK1] == 1; 155 } 156 157 static uint64_t npcm7xx_gpio_regs_read(void *opaque, hwaddr addr, 158 unsigned int size) 159 { 160 hwaddr reg = addr / sizeof(uint32_t); 161 NPCM7xxGPIOState *s = opaque; 162 uint64_t value = 0; 163 164 switch (reg) { 165 case NPCM7XX_GPIO_TLOCK1 ... NPCM7XX_GPIO_EVEN: 166 case NPCM7XX_GPIO_EVST ... NPCM7XX_GPIO_ODSC: 167 value = s->regs[reg]; 168 break; 169 170 case NPCM7XX_GPIO_EVENS ... NPCM7XX_GPIO_EVENC: 171 case NPCM7XX_GPIO_DOS ... NPCM7XX_GPIO_TLOCK2: 172 qemu_log_mask(LOG_GUEST_ERROR, 173 "%s: read from write-only register 0x%" HWADDR_PRIx "\n", 174 DEVICE(s)->canonical_path, addr); 175 break; 176 177 default: 178 qemu_log_mask(LOG_GUEST_ERROR, 179 "%s: read from invalid offset 0x%" HWADDR_PRIx "\n", 180 DEVICE(s)->canonical_path, addr); 181 break; 182 } 183 184 trace_npcm7xx_gpio_read(DEVICE(s)->canonical_path, addr, value); 185 186 return value; 187 } 188 189 static void npcm7xx_gpio_regs_write(void *opaque, hwaddr addr, uint64_t v, 190 unsigned int size) 191 { 192 hwaddr reg = addr / sizeof(uint32_t); 193 NPCM7xxGPIOState *s = opaque; 194 uint32_t value = v; 195 uint32_t diff; 196 197 trace_npcm7xx_gpio_write(DEVICE(s)->canonical_path, addr, v); 198 199 if (npcm7xx_gpio_is_locked(s)) { 200 switch (reg) { 201 case NPCM7XX_GPIO_TLOCK1: 202 if (s->regs[NPCM7XX_GPIO_TLOCK2] == NPCM7XX_GPIO_LOCK_MAGIC2 && 203 value == NPCM7XX_GPIO_LOCK_MAGIC1) { 204 s->regs[NPCM7XX_GPIO_TLOCK1] = 0; 205 s->regs[NPCM7XX_GPIO_TLOCK2] = 0; 206 } 207 break; 208 209 case NPCM7XX_GPIO_TLOCK2: 210 s->regs[reg] = value; 211 break; 212 213 default: 214 qemu_log_mask(LOG_GUEST_ERROR, 215 "%s: write to locked register @ 0x%" HWADDR_PRIx "\n", 216 DEVICE(s)->canonical_path, addr); 217 break; 218 } 219 220 return; 221 } 222 223 diff = s->regs[reg] ^ value; 224 225 switch (reg) { 226 case NPCM7XX_GPIO_TLOCK1: 227 case NPCM7XX_GPIO_TLOCK2: 228 s->regs[NPCM7XX_GPIO_TLOCK1] = 1; 229 s->regs[NPCM7XX_GPIO_TLOCK2] = 0; 230 break; 231 232 case NPCM7XX_GPIO_DIN: 233 qemu_log_mask(LOG_GUEST_ERROR, 234 "%s: write to read-only register @ 0x%" HWADDR_PRIx "\n", 235 DEVICE(s)->canonical_path, addr); 236 break; 237 238 case NPCM7XX_GPIO_POL: 239 case NPCM7XX_GPIO_DOUT: 240 case NPCM7XX_GPIO_OE: 241 case NPCM7XX_GPIO_OTYP: 242 case NPCM7XX_GPIO_PU: 243 case NPCM7XX_GPIO_PD: 244 case NPCM7XX_GPIO_IEM: 245 s->regs[reg] = value; 246 npcm7xx_gpio_update_pins(s, diff); 247 break; 248 249 case NPCM7XX_GPIO_DOS: 250 s->regs[NPCM7XX_GPIO_DOUT] |= value; 251 npcm7xx_gpio_update_pins(s, value); 252 break; 253 case NPCM7XX_GPIO_DOC: 254 s->regs[NPCM7XX_GPIO_DOUT] &= ~value; 255 npcm7xx_gpio_update_pins(s, value); 256 break; 257 case NPCM7XX_GPIO_OES: 258 s->regs[NPCM7XX_GPIO_OE] |= value; 259 npcm7xx_gpio_update_pins(s, value); 260 break; 261 case NPCM7XX_GPIO_OEC: 262 s->regs[NPCM7XX_GPIO_OE] &= ~value; 263 npcm7xx_gpio_update_pins(s, value); 264 break; 265 266 case NPCM7XX_GPIO_EVTYP: 267 case NPCM7XX_GPIO_EVBE: 268 case NPCM7XX_GPIO_EVEN: 269 s->regs[reg] = value; 270 npcm7xx_gpio_update_events(s, 0); 271 break; 272 273 case NPCM7XX_GPIO_EVENS: 274 s->regs[NPCM7XX_GPIO_EVEN] |= value; 275 npcm7xx_gpio_update_events(s, 0); 276 break; 277 case NPCM7XX_GPIO_EVENC: 278 s->regs[NPCM7XX_GPIO_EVEN] &= ~value; 279 npcm7xx_gpio_update_events(s, 0); 280 break; 281 282 case NPCM7XX_GPIO_EVST: 283 s->regs[reg] &= ~value; 284 npcm7xx_gpio_update_events(s, 0); 285 break; 286 287 case NPCM7XX_GPIO_MP: 288 case NPCM7XX_GPIO_DBNC: 289 case NPCM7XX_GPIO_OSRC: 290 case NPCM7XX_GPIO_ODSC: 291 /* Nothing to do; just store the value. */ 292 s->regs[reg] = value; 293 break; 294 295 case NPCM7XX_GPIO_OBL0: 296 case NPCM7XX_GPIO_OBL1: 297 case NPCM7XX_GPIO_OBL2: 298 case NPCM7XX_GPIO_OBL3: 299 s->regs[reg] = value; 300 qemu_log_mask(LOG_UNIMP, "%s: Blinking is not implemented\n", 301 __func__); 302 break; 303 304 case NPCM7XX_GPIO_SPLCK: 305 case NPCM7XX_GPIO_MPLCK: 306 qemu_log_mask(LOG_UNIMP, "%s: Per-pin lock is not implemented\n", 307 __func__); 308 break; 309 310 default: 311 qemu_log_mask(LOG_GUEST_ERROR, 312 "%s: write to invalid offset 0x%" HWADDR_PRIx "\n", 313 DEVICE(s)->canonical_path, addr); 314 break; 315 } 316 } 317 318 static const MemoryRegionOps npcm7xx_gpio_regs_ops = { 319 .read = npcm7xx_gpio_regs_read, 320 .write = npcm7xx_gpio_regs_write, 321 .endianness = DEVICE_NATIVE_ENDIAN, 322 .valid = { 323 .min_access_size = 4, 324 .max_access_size = 4, 325 .unaligned = false, 326 }, 327 }; 328 329 static void npcm7xx_gpio_set_input(void *opaque, int line, int level) 330 { 331 NPCM7xxGPIOState *s = opaque; 332 333 trace_npcm7xx_gpio_set_input(DEVICE(s)->canonical_path, line, level); 334 335 g_assert(line >= 0 && line < NPCM7XX_GPIO_NR_PINS); 336 337 s->ext_driven = deposit32(s->ext_driven, line, 1, level >= 0); 338 s->ext_level = deposit32(s->ext_level, line, 1, level > 0); 339 340 npcm7xx_gpio_update_pins(s, BIT(line)); 341 } 342 343 static void npcm7xx_gpio_enter_reset(Object *obj, ResetType type) 344 { 345 NPCM7xxGPIOState *s = NPCM7XX_GPIO(obj); 346 347 memset(s->regs, 0, sizeof(s->regs)); 348 349 s->regs[NPCM7XX_GPIO_PU] = s->reset_pu; 350 s->regs[NPCM7XX_GPIO_PD] = s->reset_pd; 351 s->regs[NPCM7XX_GPIO_OSRC] = s->reset_osrc; 352 s->regs[NPCM7XX_GPIO_ODSC] = s->reset_odsc; 353 } 354 355 static void npcm7xx_gpio_hold_reset(Object *obj) 356 { 357 NPCM7xxGPIOState *s = NPCM7XX_GPIO(obj); 358 359 npcm7xx_gpio_update_pins(s, -1); 360 } 361 362 static void npcm7xx_gpio_init(Object *obj) 363 { 364 NPCM7xxGPIOState *s = NPCM7XX_GPIO(obj); 365 DeviceState *dev = DEVICE(obj); 366 367 memory_region_init_io(&s->mmio, obj, &npcm7xx_gpio_regs_ops, s, 368 "regs", NPCM7XX_GPIO_REGS_SIZE); 369 sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio); 370 sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq); 371 372 qdev_init_gpio_in(dev, npcm7xx_gpio_set_input, NPCM7XX_GPIO_NR_PINS); 373 qdev_init_gpio_out(dev, s->output, NPCM7XX_GPIO_NR_PINS); 374 } 375 376 static const VMStateDescription vmstate_npcm7xx_gpio = { 377 .name = "npcm7xx-gpio", 378 .version_id = 0, 379 .minimum_version_id = 0, 380 .fields = (const VMStateField[]) { 381 VMSTATE_UINT32(pin_level, NPCM7xxGPIOState), 382 VMSTATE_UINT32(ext_level, NPCM7xxGPIOState), 383 VMSTATE_UINT32(ext_driven, NPCM7xxGPIOState), 384 VMSTATE_UINT32_ARRAY(regs, NPCM7xxGPIOState, NPCM7XX_GPIO_NR_REGS), 385 VMSTATE_END_OF_LIST(), 386 }, 387 }; 388 389 static Property npcm7xx_gpio_properties[] = { 390 /* Bit n set => pin n has pullup enabled by default. */ 391 DEFINE_PROP_UINT32("reset-pullup", NPCM7xxGPIOState, reset_pu, 0), 392 /* Bit n set => pin n has pulldown enabled by default. */ 393 DEFINE_PROP_UINT32("reset-pulldown", NPCM7xxGPIOState, reset_pd, 0), 394 /* Bit n set => pin n has high slew rate by default. */ 395 DEFINE_PROP_UINT32("reset-osrc", NPCM7xxGPIOState, reset_osrc, 0), 396 /* Bit n set => pin n has high drive strength by default. */ 397 DEFINE_PROP_UINT32("reset-odsc", NPCM7xxGPIOState, reset_odsc, 0), 398 DEFINE_PROP_END_OF_LIST(), 399 }; 400 401 static void npcm7xx_gpio_class_init(ObjectClass *klass, void *data) 402 { 403 ResettableClass *reset = RESETTABLE_CLASS(klass); 404 DeviceClass *dc = DEVICE_CLASS(klass); 405 406 QEMU_BUILD_BUG_ON(NPCM7XX_GPIO_REGS_END > NPCM7XX_GPIO_NR_REGS); 407 408 dc->desc = "NPCM7xx GPIO Controller"; 409 dc->vmsd = &vmstate_npcm7xx_gpio; 410 reset->phases.enter = npcm7xx_gpio_enter_reset; 411 reset->phases.hold = npcm7xx_gpio_hold_reset; 412 device_class_set_props(dc, npcm7xx_gpio_properties); 413 } 414 415 static const TypeInfo npcm7xx_gpio_types[] = { 416 { 417 .name = TYPE_NPCM7XX_GPIO, 418 .parent = TYPE_SYS_BUS_DEVICE, 419 .instance_size = sizeof(NPCM7xxGPIOState), 420 .class_init = npcm7xx_gpio_class_init, 421 .instance_init = npcm7xx_gpio_init, 422 }, 423 }; 424 DEFINE_TYPES(npcm7xx_gpio_types); 425