arch/mips/sgi-ip22/ip22-gio.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 #include <linux/export.h>
   3 #include <linux/kernel.h>
   4 #include <linux/init.h>
   5 #include <linux/slab.h>
   6
   7 #include <asm/addrspace.h>
   8 #include <asm/paccess.h>
   9 #include <asm/gio_device.h>
  10 #include <asm/sgi/gio.h>
  11 #include <asm/sgi/hpc3.h>
  12 #include <asm/sgi/mc.h>
  13 #include <asm/sgi/ip22.h>
  14
  15 static const struct bus_type gio_bus_type;
  16
  17 static struct {
  18         const char *name;
  19         __u8       id;
  20 } gio_name_table[] = {
  21         { .name = "SGI Impact", .id = 0x10 },
  22         { .name = "Phobos G160", .id = 0x35 },
  23         { .name = "Phobos G130", .id = 0x36 },
  24         { .name = "Phobos G100", .id = 0x37 },
  25         { .name = "Set Engineering GFE", .id = 0x38 },
  26         /* fake IDs */
  27         { .name = "SGI Newport", .id = 0x7e },
  28         { .name = "SGI GR2/GR3", .id = 0x7f },
  29 };
  30
  31 static void gio_bus_release(struct device *dev)
  32 {
  33         kfree(dev);
  34 }
  35
  36 static struct device gio_bus = {
  37         .init_name = "gio",
  38         .release = &gio_bus_release,
  39 };
  40
  41 /**
  42  * gio_match_device - Tell if an of_device structure has a matching
  43  * gio_match structure
  44  * @ids: array of of device match structures to search in
  45  * @dev: the of device structure to match against
  46  *
  47  * Used by a driver to check whether an of_device present in the
  48  * system is in its list of supported devices.
  49  */
  50 static const struct gio_device_id *
  51 gio_match_device(const struct gio_device_id *match,
  52                  const struct gio_device *dev)
  53 {
  54         const struct gio_device_id *ids;
  55
  56         for (ids = match; ids->id != 0xff; ids++)
  57                 if (ids->id == dev->id.id)
  58                         return ids;
  59
  60         return NULL;
  61 }
  62
  63 struct gio_device *gio_dev_get(struct gio_device *dev)
  64 {
  65         struct device *tmp;
  66
  67         if (!dev)
  68                 return NULL;
  69         tmp = get_device(&dev->dev);
  70         if (tmp)
  71                 return to_gio_device(tmp);
  72         else
  73                 return NULL;
  74 }
  75 EXPORT_SYMBOL_GPL(gio_dev_get);
  76
  77 void gio_dev_put(struct gio_device *dev)
  78 {
  79         if (dev)
  80                 put_device(&dev->dev);
  81 }
  82 EXPORT_SYMBOL_GPL(gio_dev_put);
  83
  84 /**
  85  * gio_release_dev - free an gio device structure when all users of it are finished.
  86  * @dev: device that's been disconnected
  87  *
  88  * Will be called only by the device core when all users of this gio device are
  89  * done.
  90  */
  91 void gio_release_dev(struct device *dev)
  92 {
  93         struct gio_device *giodev;
  94
  95         giodev = to_gio_device(dev);
  96         kfree(giodev);
  97 }
  98 EXPORT_SYMBOL_GPL(gio_release_dev);
  99
 100 int gio_device_register(struct gio_device *giodev)
 101 {
 102         giodev->dev.bus = &gio_bus_type;
 103         giodev->dev.parent = &gio_bus;
 104         return device_register(&giodev->dev);
 105 }
 106 EXPORT_SYMBOL_GPL(gio_device_register);
 107
 108 void gio_device_unregister(struct gio_device *giodev)
 109 {
 110         device_unregister(&giodev->dev);
 111 }
 112 EXPORT_SYMBOL_GPL(gio_device_unregister);
 113
 114 static int gio_bus_match(struct device *dev, const struct device_driver *drv)
 115 {
 116         struct gio_device *gio_dev = to_gio_device(dev);
 117         struct gio_driver *gio_drv = to_gio_driver(drv);
 118
 119         return gio_match_device(gio_drv->id_table, gio_dev) != NULL;
 120 }
 121
 122 static int gio_device_probe(struct device *dev)
 123 {
 124         int error = -ENODEV;
 125         struct gio_driver *drv;
 126         struct gio_device *gio_dev;
 127         const struct gio_device_id *match;
 128
 129         drv = to_gio_driver(dev->driver);
 130         gio_dev = to_gio_device(dev);
 131
 132         if (!drv->probe)
 133                 return error;
 134
 135         gio_dev_get(gio_dev);
 136
 137         match = gio_match_device(drv->id_table, gio_dev);
 138         if (match)
 139                 error = drv->probe(gio_dev, match);
 140         if (error)
 141                 gio_dev_put(gio_dev);
 142
 143         return error;
 144 }
 145
 146 static void gio_device_remove(struct device *dev)
 147 {
 148         struct gio_device *gio_dev = to_gio_device(dev);
 149         struct gio_driver *drv = to_gio_driver(dev->driver);
 150
 151         if (drv->remove)
 152                 drv->remove(gio_dev);
 153 }
 154
 155 static void gio_device_shutdown(struct device *dev)
 156 {
 157         struct gio_device *gio_dev = to_gio_device(dev);
 158         struct gio_driver *drv = to_gio_driver(dev->driver);
 159
 160         if (dev->driver && drv->shutdown)
 161                 drv->shutdown(gio_dev);
 162 }
 163
 164 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 165                              char *buf)
 166 {
 167         struct gio_device *gio_dev = to_gio_device(dev);
 168
 169         return sysfs_emit(buf, "gio:%x\n", gio_dev->id.id);
 170 }
 171 static DEVICE_ATTR_RO(modalias);
 172
 173 static ssize_t name_show(struct device *dev,
 174                          struct device_attribute *attr, char *buf)
 175 {
 176         struct gio_device *giodev;
 177
 178         giodev = to_gio_device(dev);
 179         return sysfs_emit(buf, "%s\n", giodev->name);
 180 }
 181 static DEVICE_ATTR_RO(name);
 182
 183 static ssize_t id_show(struct device *dev,
 184                        struct device_attribute *attr, char *buf)
 185 {
 186         struct gio_device *giodev;
 187
 188         giodev = to_gio_device(dev);
 189         return sysfs_emit(buf, "%x\n", giodev->id.id);
 190 }
 191 static DEVICE_ATTR_RO(id);
 192
 193 static struct attribute *gio_dev_attrs[] = {
 194         &dev_attr_modalias.attr,
 195         &dev_attr_name.attr,
 196         &dev_attr_id.attr,
 197         NULL,
 198 };
 199 ATTRIBUTE_GROUPS(gio_dev);
 200
 201 static int gio_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
 202 {
 203         const struct gio_device *gio_dev = to_gio_device(dev);
 204
 205         add_uevent_var(env, "MODALIAS=gio:%x", gio_dev->id.id);
 206         return 0;
 207 }
 208
 209 int gio_register_driver(struct gio_driver *drv)
 210 {
 211         /* initialize common driver fields */
 212         if (!drv->driver.name)
 213                 drv->driver.name = drv->name;
 214         if (!drv->driver.owner)
 215                 drv->driver.owner = drv->owner;
 216         drv->driver.bus = &gio_bus_type;
 217
 218         /* register with core */
 219         return driver_register(&drv->driver);
 220 }
 221 EXPORT_SYMBOL_GPL(gio_register_driver);
 222
 223 void gio_unregister_driver(struct gio_driver *drv)
 224 {
 225         driver_unregister(&drv->driver);
 226 }
 227 EXPORT_SYMBOL_GPL(gio_unregister_driver);
 228
 229 void gio_set_master(struct gio_device *dev)
 230 {
 231         u32 tmp = sgimc->giopar;
 232
 233         switch (dev->slotno) {
 234         case 0:
 235                 tmp |= SGIMC_GIOPAR_MASTERGFX;
 236                 break;
 237         case 1:
 238                 tmp |= SGIMC_GIOPAR_MASTEREXP0;
 239                 break;
 240         case 2:
 241                 tmp |= SGIMC_GIOPAR_MASTEREXP1;
 242                 break;
 243         }
 244         sgimc->giopar = tmp;
 245 }
 246 EXPORT_SYMBOL_GPL(gio_set_master);
 247
 248 static void ip22_gio_set_64bit(int slotno)
 249 {
 250         u32 tmp = sgimc->giopar;
 251
 252         switch (slotno) {
 253         case 0:
 254                 tmp |= SGIMC_GIOPAR_GFX64;
 255                 break;
 256         case 1:
 257                 tmp |= SGIMC_GIOPAR_EXP064;
 258                 break;
 259         case 2:
 260                 tmp |= SGIMC_GIOPAR_EXP164;
 261                 break;
 262         }
 263         sgimc->giopar = tmp;
 264 }
 265
 266 static int ip22_gio_id(unsigned long addr, u32 *res)
 267 {
 268         u8 tmp8;
 269         u8 tmp16;
 270         u32 tmp32;
 271         u8 *ptr8;
 272         u16 *ptr16;
 273         u32 *ptr32;
 274
 275         ptr32 = (void *)CKSEG1ADDR(addr);
 276         if (!get_dbe(tmp32, ptr32)) {
 277                 /*
 278                  * We got no DBE, but this doesn't mean anything.
 279                  * If GIO is pipelined (which can't be disabled
 280                  * for GFX slot) we don't get a DBE, but we see
 281                  * the transfer size as data. So we do an 8bit
 282                  * and a 16bit access and check whether the common
 283                  * data matches
 284                  */
 285                 ptr8 = (void *)CKSEG1ADDR(addr + 3);
 286                 if (get_dbe(tmp8, ptr8)) {
 287                         /*
 288                          * 32bit access worked, but 8bit doesn't
 289                          * so we don't see phantom reads on
 290                          * a pipelined bus, but a real card which
 291                          * doesn't support 8 bit reads
 292                          */
 293                         *res = tmp32;
 294                         return 1;
 295                 }
 296                 ptr16 = (void *)CKSEG1ADDR(addr + 2);
 297                 get_dbe(tmp16, ptr16);
 298                 if (tmp8 == (tmp16 & 0xff) &&
 299                     tmp8 == (tmp32 & 0xff) &&
 300                     tmp16 == (tmp32 & 0xffff)) {
 301                         *res = tmp32;
 302                         return 1;
 303                 }
 304         }
 305         return 0; /* nothing here */
 306 }
 307
 308 #define HQ2_MYSTERY_OFFS       0x6A07C
 309 #define NEWPORT_USTATUS_OFFS   0xF133C
 310
 311 static int ip22_is_gr2(unsigned long addr)
 312 {
 313         u32 tmp;
 314         u32 *ptr;
 315
 316         /* HQ2 only allows 32bit accesses */
 317         ptr = (void *)CKSEG1ADDR(addr + HQ2_MYSTERY_OFFS);
 318         if (!get_dbe(tmp, ptr)) {
 319                 if (tmp == 0xdeadbeef)
 320                         return 1;
 321         }
 322         return 0;
 323 }
 324
 325
 326 static void ip22_check_gio(int slotno, unsigned long addr, int irq)
 327 {
 328         const char *name = "Unknown";
 329         struct gio_device *gio_dev;
 330         u32 tmp;
 331         __u8 id;
 332         int i;
 333
 334         /* first look for GR2/GR3 by checking mystery register */
 335         if (ip22_is_gr2(addr))
 336                 tmp = 0x7f;
 337         else {
 338                 if (!ip22_gio_id(addr, &tmp)) {
 339                         /*
 340                          * no GIO signature at start address of slot
 341                          * since Newport doesn't have one, we check if
 342                          * user status register is readable
 343                          */
 344                         if (ip22_gio_id(addr + NEWPORT_USTATUS_OFFS, &tmp))
 345                                 tmp = 0x7e;
 346                         else
 347                                 tmp = 0;
 348                 }
 349         }
 350         if (tmp) {
 351                 id = GIO_ID(tmp);
 352                 if (tmp & GIO_32BIT_ID) {
 353                         if (tmp & GIO_64BIT_IFACE)
 354                                 ip22_gio_set_64bit(slotno);
 355                 }
 356                 for (i = 0; i < ARRAY_SIZE(gio_name_table); i++) {
 357                         if (id == gio_name_table[i].id) {
 358                                 name = gio_name_table[i].name;
 359                                 break;
 360                         }
 361                 }
 362                 printk(KERN_INFO "GIO: slot %d : %s (id %x)\n",
 363                        slotno, name, id);
 364                 gio_dev = kzalloc(sizeof *gio_dev, GFP_KERNEL);
 365                 if (!gio_dev)
 366                         return;
 367                 gio_dev->name = name;
 368                 gio_dev->slotno = slotno;
 369                 gio_dev->id.id = id;
 370                 gio_dev->resource.start = addr;
 371                 gio_dev->resource.end = addr + 0x3fffff;
 372                 gio_dev->resource.flags = IORESOURCE_MEM;
 373                 gio_dev->irq = irq;
 374                 dev_set_name(&gio_dev->dev, "%d", slotno);
 375                 gio_device_register(gio_dev);
 376         } else
 377                 printk(KERN_INFO "GIO: slot %d : Empty\n", slotno);
 378 }
 379
 380 static const struct bus_type gio_bus_type = {
 381         .name      = "gio",
 382         .dev_groups = gio_dev_groups,
 383         .match     = gio_bus_match,
 384         .probe     = gio_device_probe,
 385         .remove    = gio_device_remove,
 386         .shutdown  = gio_device_shutdown,
 387         .uevent    = gio_device_uevent,
 388 };
 389
 390 static struct resource gio_bus_resource = {
 391         .start = GIO_SLOT_GFX_BASE,
 392         .end   = GIO_SLOT_GFX_BASE + 0x9fffff,
 393         .name  = "GIO Bus",
 394         .flags = IORESOURCE_MEM,
 395 };
 396
 397 static int __init ip22_gio_init(void)
 398 {
 399         unsigned int pbdma __maybe_unused;
 400         int ret;
 401
 402         ret = device_register(&gio_bus);
 403         if (ret) {
 404                 put_device(&gio_bus);
 405                 return ret;
 406         }
 407
 408         ret = bus_register(&gio_bus_type);
 409         if (!ret) {
 410                 request_resource(&iomem_resource, &gio_bus_resource);
 411                 printk(KERN_INFO "GIO: Probing bus...\n");
 412
 413                 if (ip22_is_fullhouse()) {
 414                         /* Indigo2 */
 415                         ip22_check_gio(0, GIO_SLOT_GFX_BASE, SGI_GIO_1_IRQ);
 416                         ip22_check_gio(1, GIO_SLOT_EXP0_BASE, SGI_GIO_1_IRQ);
 417                 } else {
 418                         /* Indy/Challenge S */
 419                         if (get_dbe(pbdma, (unsigned int *)&hpc3c1->pbdma[1]))
 420                                 ip22_check_gio(0, GIO_SLOT_GFX_BASE,
 421                                                SGI_GIO_0_IRQ);
 422                         ip22_check_gio(1, GIO_SLOT_EXP0_BASE, SGI_GIOEXP0_IRQ);
 423                         ip22_check_gio(2, GIO_SLOT_EXP1_BASE, SGI_GIOEXP1_IRQ);
 424                 }
 425         } else
 426                 device_unregister(&gio_bus);
 427
 428         return ret;
 429 }
 430
 431 subsys_initcall(ip22_gio_init);