drivers/mfd/vexpress-sysreg.c

   1 /*
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License version 2 as
   4  * published by the Free Software Foundation.
   5  *
   6  * This program is distributed in the hope that it will be useful,
   7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9  * GNU General Public License for more details.
  10  *
  11  * Copyright (C) 2012 ARM Limited
  12  */
  13
  14 #include <linux/err.h>
  15 #include <linux/gpio.h>
  16 #include <linux/io.h>
  17 #include <linux/leds.h>
  18 #include <linux/of_address.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/regulator/driver.h>
  21 #include <linux/slab.h>
  22 #include <linux/stat.h>
  23 #include <linux/timer.h>
  24 #include <linux/vexpress.h>
  25
  26 #define SYS_ID                  0x000
  27 #define SYS_SW                  0x004
  28 #define SYS_LED                 0x008
  29 #define SYS_100HZ               0x024
  30 #define SYS_FLAGS               0x030
  31 #define SYS_FLAGSSET            0x030
  32 #define SYS_FLAGSCLR            0x034
  33 #define SYS_NVFLAGS             0x038
  34 #define SYS_NVFLAGSSET          0x038
  35 #define SYS_NVFLAGSCLR          0x03c
  36 #define SYS_MCI                 0x048
  37 #define SYS_FLASH               0x04c
  38 #define SYS_CFGSW               0x058
  39 #define SYS_24MHZ               0x05c
  40 #define SYS_MISC                0x060
  41 #define SYS_DMA                 0x064
  42 #define SYS_PROCID0             0x084
  43 #define SYS_PROCID1             0x088
  44 #define SYS_CFGDATA             0x0a0
  45 #define SYS_CFGCTRL             0x0a4
  46 #define SYS_CFGSTAT             0x0a8
  47
  48 #define SYS_HBI_MASK            0xfff
  49 #define SYS_ID_HBI_SHIFT        16
  50 #define SYS_PROCIDx_HBI_SHIFT   0
  51
  52 #define SYS_LED_LED(n)          (1 << (n))
  53
  54 #define SYS_MCI_CARDIN          (1 << 0)
  55 #define SYS_MCI_WPROT           (1 << 1)
  56
  57 #define SYS_FLASH_WPn           (1 << 0)
  58
  59 #define SYS_MISC_MASTERSITE     (1 << 14)
  60
  61 #define SYS_CFGCTRL_START       (1 << 31)
  62 #define SYS_CFGCTRL_WRITE       (1 << 30)
  63 #define SYS_CFGCTRL_DCC(n)      (((n) & 0xf) << 26)
  64 #define SYS_CFGCTRL_FUNC(n)     (((n) & 0x3f) << 20)
  65 #define SYS_CFGCTRL_SITE(n)     (((n) & 0x3) << 16)
  66 #define SYS_CFGCTRL_POSITION(n) (((n) & 0xf) << 12)
  67 #define SYS_CFGCTRL_DEVICE(n)   (((n) & 0xfff) << 0)
  68
  69 #define SYS_CFGSTAT_ERR         (1 << 1)
  70 #define SYS_CFGSTAT_COMPLETE    (1 << 0)
  71
  72
  73 static void __iomem *vexpress_sysreg_base;
  74 static struct device *vexpress_sysreg_dev;
  75 static int vexpress_master_site;
  76
  77
  78 void vexpress_flags_set(u32 data)
  79 {
  80         writel(~0, vexpress_sysreg_base + SYS_FLAGSCLR);
  81         writel(data, vexpress_sysreg_base + SYS_FLAGSSET);
  82 }
  83
  84 u32 vexpress_get_procid(int site)
  85 {
  86         if (site == VEXPRESS_SITE_MASTER)
  87                 site = vexpress_master_site;
  88
  89         return readl(vexpress_sysreg_base + (site == VEXPRESS_SITE_DB1 ?
  90                         SYS_PROCID0 : SYS_PROCID1));
  91 }
  92
  93 u32 vexpress_get_hbi(int site)
  94 {
  95         u32 id;
  96
  97         switch (site) {
  98         case VEXPRESS_SITE_MB:
  99                 id = readl(vexpress_sysreg_base + SYS_ID);
 100                 return (id >> SYS_ID_HBI_SHIFT) & SYS_HBI_MASK;
 101         case VEXPRESS_SITE_MASTER:
 102         case VEXPRESS_SITE_DB1:
 103         case VEXPRESS_SITE_DB2:
 104                 id = vexpress_get_procid(site);
 105                 return (id >> SYS_PROCIDx_HBI_SHIFT) & SYS_HBI_MASK;
 106         }
 107
 108         return ~0;
 109 }
 110
 111 void __iomem *vexpress_get_24mhz_clock_base(void)
 112 {
 113         return vexpress_sysreg_base + SYS_24MHZ;
 114 }
 115
 116
 117 static void vexpress_sysreg_find_prop(struct device_node *node,
 118                 const char *name, u32 *val)
 119 {
 120         of_node_get(node);
 121         while (node) {
 122                 if (of_property_read_u32(node, name, val) == 0) {
 123                         of_node_put(node);
 124                         return;
 125                 }
 126                 node = of_get_next_parent(node);
 127         }
 128 }
 129
 130 unsigned __vexpress_get_site(struct device *dev, struct device_node *node)
 131 {
 132         u32 site = 0;
 133
 134         WARN_ON(dev && node && dev->of_node != node);
 135         if (dev && !node)
 136                 node = dev->of_node;
 137
 138         if (node) {
 139                 vexpress_sysreg_find_prop(node, "arm,vexpress,site", &site);
 140         } else if (dev && dev->bus == &platform_bus_type) {
 141                 struct platform_device *pdev = to_platform_device(dev);
 142
 143                 if (pdev->num_resources == 1 &&
 144                                 pdev->resource[0].flags == IORESOURCE_BUS)
 145                         site = pdev->resource[0].start;
 146         } else if (dev && strncmp(dev_name(dev), "ct:", 3) == 0) {
 147                 site = VEXPRESS_SITE_MASTER;
 148         }
 149
 150         if (site == VEXPRESS_SITE_MASTER)
 151                 site = vexpress_master_site;
 152
 153         return site;
 154 }
 155
 156
 157 struct vexpress_sysreg_config_func {
 158         u32 template;
 159         u32 device;
 160 };
 161
 162 static struct vexpress_config_bridge *vexpress_sysreg_config_bridge;
 163 static struct timer_list vexpress_sysreg_config_timer;
 164 static u32 *vexpress_sysreg_config_data;
 165 static int vexpress_sysreg_config_tries;
 166
 167 static void *vexpress_sysreg_config_func_get(struct device *dev,
 168                 struct device_node *node)
 169 {
 170         struct vexpress_sysreg_config_func *config_func;
 171         u32 site;
 172         u32 position = 0;
 173         u32 dcc = 0;
 174         u32 func_device[2];
 175         int err = -EFAULT;
 176
 177         if (node) {
 178                 of_node_get(node);
 179                 vexpress_sysreg_find_prop(node, "arm,vexpress,site", &site);
 180                 vexpress_sysreg_find_prop(node, "arm,vexpress,position",
 181                                 &position);
 182                 vexpress_sysreg_find_prop(node, "arm,vexpress,dcc", &dcc);
 183                 err = of_property_read_u32_array(node,
 184                                 "arm,vexpress-sysreg,func", func_device,
 185                                 ARRAY_SIZE(func_device));
 186                 of_node_put(node);
 187         } else if (dev && dev->bus == &platform_bus_type) {
 188                 struct platform_device *pdev = to_platform_device(dev);
 189
 190                 if (pdev->num_resources == 1 &&
 191                                 pdev->resource[0].flags == IORESOURCE_BUS) {
 192                         site = pdev->resource[0].start;
 193                         func_device[0] = pdev->resource[0].end;
 194                         func_device[1] = pdev->id;
 195                         err = 0;
 196                 }
 197         }
 198         if (err)
 199                 return NULL;
 200
 201         config_func = kzalloc(sizeof(*config_func), GFP_KERNEL);
 202         if (!config_func)
 203                 return NULL;
 204
 205         config_func->template = SYS_CFGCTRL_DCC(dcc);
 206         config_func->template |= SYS_CFGCTRL_FUNC(func_device[0]);
 207         config_func->template |= SYS_CFGCTRL_SITE(site == VEXPRESS_SITE_MASTER ?
 208                         vexpress_master_site : site);
 209         config_func->template |= SYS_CFGCTRL_POSITION(position);
 210         config_func->device |= func_device[1];
 211
 212         dev_dbg(vexpress_sysreg_dev, "func 0x%p = 0x%x, %d\n", config_func,
 213                         config_func->template, config_func->device);
 214
 215         return config_func;
 216 }
 217
 218 static void vexpress_sysreg_config_func_put(void *func)
 219 {
 220         kfree(func);
 221 }
 222
 223 static int vexpress_sysreg_config_func_exec(void *func, int offset,
 224                 bool write, u32 *data)
 225 {
 226         int status;
 227         struct vexpress_sysreg_config_func *config_func = func;
 228         u32 command;
 229
 230         if (WARN_ON(!vexpress_sysreg_base))
 231                 return -ENOENT;
 232
 233         command = readl(vexpress_sysreg_base + SYS_CFGCTRL);
 234         if (WARN_ON(command & SYS_CFGCTRL_START))
 235                 return -EBUSY;
 236
 237         command = SYS_CFGCTRL_START;
 238         command |= write ? SYS_CFGCTRL_WRITE : 0;
 239         command |= config_func->template;
 240         command |= SYS_CFGCTRL_DEVICE(config_func->device + offset);
 241
 242         /* Use a canary for reads */
 243         if (!write)
 244                 *data = 0xdeadbeef;
 245
 246         dev_dbg(vexpress_sysreg_dev, "command %x, data %x\n",
 247                         command, *data);
 248         writel(*data, vexpress_sysreg_base + SYS_CFGDATA);
 249         writel(0, vexpress_sysreg_base + SYS_CFGSTAT);
 250         writel(command, vexpress_sysreg_base + SYS_CFGCTRL);
 251         mb();
 252
 253         if (vexpress_sysreg_dev) {
 254                 /* Schedule completion check */
 255                 if (!write)
 256                         vexpress_sysreg_config_data = data;
 257                 vexpress_sysreg_config_tries = 100;
 258                 mod_timer(&vexpress_sysreg_config_timer,
 259                                 jiffies + usecs_to_jiffies(100));
 260                 status = VEXPRESS_CONFIG_STATUS_WAIT;
 261         } else {
 262                 /* Early execution, no timer available, have to spin */
 263                 u32 cfgstat;
 264
 265                 do {
 266                         cpu_relax();
 267                         cfgstat = readl(vexpress_sysreg_base + SYS_CFGSTAT);
 268                 } while (!cfgstat);
 269
 270                 if (!write && (cfgstat & SYS_CFGSTAT_COMPLETE))
 271                         *data = readl(vexpress_sysreg_base + SYS_CFGDATA);
 272                 status = VEXPRESS_CONFIG_STATUS_DONE;
 273
 274                 if (cfgstat & SYS_CFGSTAT_ERR)
 275                         status = -EINVAL;
 276         }
 277
 278         return status;
 279 }
 280
 281 struct vexpress_config_bridge_info vexpress_sysreg_config_bridge_info = {
 282         .name = "vexpress-sysreg",
 283         .func_get = vexpress_sysreg_config_func_get,
 284         .func_put = vexpress_sysreg_config_func_put,
 285         .func_exec = vexpress_sysreg_config_func_exec,
 286 };
 287
 288 static void vexpress_sysreg_config_complete(unsigned long data)
 289 {
 290         int status = VEXPRESS_CONFIG_STATUS_DONE;
 291         u32 cfgstat = readl(vexpress_sysreg_base + SYS_CFGSTAT);
 292
 293         if (cfgstat & SYS_CFGSTAT_ERR)
 294                 status = -EINVAL;
 295         if (!vexpress_sysreg_config_tries--)
 296                 status = -ETIMEDOUT;
 297
 298         if (status < 0) {
 299                 dev_err(vexpress_sysreg_dev, "error %d\n", status);
 300         } else if (!(cfgstat & SYS_CFGSTAT_COMPLETE)) {
 301                 mod_timer(&vexpress_sysreg_config_timer,
 302                                 jiffies + usecs_to_jiffies(50));
 303                 return;
 304         }
 305
 306         if (vexpress_sysreg_config_data) {
 307                 *vexpress_sysreg_config_data = readl(vexpress_sysreg_base +
 308                                 SYS_CFGDATA);
 309                 dev_dbg(vexpress_sysreg_dev, "read data %x\n",
 310                                 *vexpress_sysreg_config_data);
 311                 vexpress_sysreg_config_data = NULL;
 312         }
 313
 314         vexpress_config_complete(vexpress_sysreg_config_bridge, status);
 315 }
 316
 317
 318 void vexpress_sysreg_setup(struct device_node *node)
 319 {
 320         if (WARN_ON(!vexpress_sysreg_base))
 321                 return;
 322
 323         if (readl(vexpress_sysreg_base + SYS_MISC) & SYS_MISC_MASTERSITE)
 324                 vexpress_master_site = VEXPRESS_SITE_DB2;
 325         else
 326                 vexpress_master_site = VEXPRESS_SITE_DB1;
 327
 328         vexpress_sysreg_config_bridge = vexpress_config_bridge_register(
 329                         node, &vexpress_sysreg_config_bridge_info);
 330         WARN_ON(!vexpress_sysreg_config_bridge);
 331 }
 332
 333 void __init vexpress_sysreg_early_init(void __iomem *base)
 334 {
 335         vexpress_sysreg_base = base;
 336         vexpress_sysreg_setup(NULL);
 337 }
 338
 339 void __init vexpress_sysreg_of_early_init(void)
 340 {
 341         struct device_node *node;
 342
 343         if (vexpress_sysreg_base)
 344                 return;
 345
 346         node = of_find_compatible_node(NULL, NULL, "arm,vexpress-sysreg");
 347         if (node) {
 348                 vexpress_sysreg_base = of_iomap(node, 0);
 349                 vexpress_sysreg_setup(node);
 350         }
 351 }
 352
 353
 354 #define VEXPRESS_SYSREG_GPIO(_name, _reg, _value) \
 355         [VEXPRESS_GPIO_##_name] = { \
 356                 .reg = _reg, \
 357                 .value = _reg##_##_value, \
 358         }
 359
 360 static struct vexpress_sysreg_gpio {
 361         unsigned long reg;
 362         u32 value;
 363 } vexpress_sysreg_gpios[] = {
 364         VEXPRESS_SYSREG_GPIO(MMC_CARDIN,        SYS_MCI,        CARDIN),
 365         VEXPRESS_SYSREG_GPIO(MMC_WPROT,         SYS_MCI,        WPROT),
 366         VEXPRESS_SYSREG_GPIO(FLASH_WPn,         SYS_FLASH,      WPn),
 367         VEXPRESS_SYSREG_GPIO(LED0,              SYS_LED,        LED(0)),
 368         VEXPRESS_SYSREG_GPIO(LED1,              SYS_LED,        LED(1)),
 369         VEXPRESS_SYSREG_GPIO(LED2,              SYS_LED,        LED(2)),
 370         VEXPRESS_SYSREG_GPIO(LED3,              SYS_LED,        LED(3)),
 371         VEXPRESS_SYSREG_GPIO(LED4,              SYS_LED,        LED(4)),
 372         VEXPRESS_SYSREG_GPIO(LED5,              SYS_LED,        LED(5)),
 373         VEXPRESS_SYSREG_GPIO(LED6,              SYS_LED,        LED(6)),
 374         VEXPRESS_SYSREG_GPIO(LED7,              SYS_LED,        LED(7)),
 375 };
 376
 377 static int vexpress_sysreg_gpio_direction_input(struct gpio_chip *chip,
 378                                        unsigned offset)
 379 {
 380         return 0;
 381 }
 382
 383 static int vexpress_sysreg_gpio_get(struct gpio_chip *chip,
 384                                        unsigned offset)
 385 {
 386         struct vexpress_sysreg_gpio *gpio = &vexpress_sysreg_gpios[offset];
 387         u32 reg_value = readl(vexpress_sysreg_base + gpio->reg);
 388
 389         return !!(reg_value & gpio->value);
 390 }
 391
 392 static void vexpress_sysreg_gpio_set(struct gpio_chip *chip,
 393                                        unsigned offset, int value)
 394 {
 395         struct vexpress_sysreg_gpio *gpio = &vexpress_sysreg_gpios[offset];
 396         u32 reg_value = readl(vexpress_sysreg_base + gpio->reg);
 397
 398         if (value)
 399                 reg_value |= gpio->value;
 400         else
 401                 reg_value &= ~gpio->value;
 402
 403         writel(reg_value, vexpress_sysreg_base + gpio->reg);
 404 }
 405
 406 static int vexpress_sysreg_gpio_direction_output(struct gpio_chip *chip,
 407                                                 unsigned offset, int value)
 408 {
 409         vexpress_sysreg_gpio_set(chip, offset, value);
 410
 411         return 0;
 412 }
 413
 414 static struct gpio_chip vexpress_sysreg_gpio_chip = {
 415         .label = "vexpress-sysreg",
 416         .direction_input = vexpress_sysreg_gpio_direction_input,
 417         .direction_output = vexpress_sysreg_gpio_direction_output,
 418         .get = vexpress_sysreg_gpio_get,
 419         .set = vexpress_sysreg_gpio_set,
 420         .ngpio = ARRAY_SIZE(vexpress_sysreg_gpios),
 421         .base = 0,
 422 };
 423
 424
 425 #define VEXPRESS_SYSREG_GREEN_LED(_name, _default_trigger, _gpio) \
 426         { \
 427                 .name = "v2m:green:"_name, \
 428                 .default_trigger = _default_trigger, \
 429                 .gpio = VEXPRESS_GPIO_##_gpio, \
 430         }
 431
 432 struct gpio_led vexpress_sysreg_leds[] = {
 433         VEXPRESS_SYSREG_GREEN_LED("user1",      "heartbeat",    LED0),
 434         VEXPRESS_SYSREG_GREEN_LED("user2",      "mmc0",         LED1),
 435         VEXPRESS_SYSREG_GREEN_LED("user3",      "cpu0",         LED2),
 436         VEXPRESS_SYSREG_GREEN_LED("user4",      "cpu1",         LED3),
 437         VEXPRESS_SYSREG_GREEN_LED("user5",      "cpu2",         LED4),
 438         VEXPRESS_SYSREG_GREEN_LED("user6",      "cpu3",         LED5),
 439         VEXPRESS_SYSREG_GREEN_LED("user7",      "cpu4",         LED6),
 440         VEXPRESS_SYSREG_GREEN_LED("user8",      "cpu5",         LED7),
 441 };
 442
 443 struct gpio_led_platform_data vexpress_sysreg_leds_pdata = {
 444         .num_leds = ARRAY_SIZE(vexpress_sysreg_leds),
 445         .leds = vexpress_sysreg_leds,
 446 };
 447
 448
 449 static ssize_t vexpress_sysreg_sys_id_show(struct device *dev,
 450                 struct device_attribute *attr, char *buf)
 451 {
 452         return sprintf(buf, "0x%08x\n", readl(vexpress_sysreg_base + SYS_ID));
 453 }
 454
 455 DEVICE_ATTR(sys_id, S_IRUGO, vexpress_sysreg_sys_id_show, NULL);
 456
 457 static int vexpress_sysreg_probe(struct platform_device *pdev)
 458 {
 459         int err;
 460         struct resource *res = platform_get_resource(pdev,
 461                         IORESOURCE_MEM, 0);
 462
 463         if (!devm_request_mem_region(&pdev->dev, res->start,
 464                         resource_size(res), pdev->name)) {
 465                 dev_err(&pdev->dev, "Failed to request memory region!\n");
 466                 return -EBUSY;
 467         }
 468
 469         if (!vexpress_sysreg_base) {
 470                 vexpress_sysreg_base = devm_ioremap(&pdev->dev, res->start,
 471                                 resource_size(res));
 472                 vexpress_sysreg_setup(pdev->dev.of_node);
 473         }
 474
 475         if (!vexpress_sysreg_base) {
 476                 dev_err(&pdev->dev, "Failed to obtain base address!\n");
 477                 return -EFAULT;
 478         }
 479
 480         setup_timer(&vexpress_sysreg_config_timer,
 481                         vexpress_sysreg_config_complete, 0);
 482
 483         vexpress_sysreg_gpio_chip.dev = &pdev->dev;
 484         err = gpiochip_add(&vexpress_sysreg_gpio_chip);
 485         if (err) {
 486                 vexpress_config_bridge_unregister(
 487                                 vexpress_sysreg_config_bridge);
 488                 dev_err(&pdev->dev, "Failed to register GPIO chip! (%d)\n",
 489                                 err);
 490                 return err;
 491         }
 492
 493         platform_device_register_data(vexpress_sysreg_dev, "leds-gpio",
 494                         PLATFORM_DEVID_AUTO, &vexpress_sysreg_leds_pdata,
 495                         sizeof(vexpress_sysreg_leds_pdata));
 496
 497         vexpress_sysreg_dev = &pdev->dev;
 498
 499         device_create_file(vexpress_sysreg_dev, &dev_attr_sys_id);
 500
 501         return 0;
 502 }
 503
 504 static const struct of_device_id vexpress_sysreg_match[] = {
 505         { .compatible = "arm,vexpress-sysreg", },
 506         {},
 507 };
 508
 509 static struct platform_driver vexpress_sysreg_driver = {
 510         .driver = {
 511                 .name = "vexpress-sysreg",
 512                 .of_match_table = vexpress_sysreg_match,
 513         },
 514         .probe = vexpress_sysreg_probe,
 515 };
 516
 517 static int __init vexpress_sysreg_init(void)
 518 {
 519         vexpress_sysreg_of_early_init();
 520         return platform_driver_register(&vexpress_sysreg_driver);
 521 }
 522 core_initcall(vexpress_sysreg_init);