hw/xen/xen-host-pci-device.c

   1 /*
   2  * Copyright (C) 2011       Citrix Ltd.
   3  *
   4  * This work is licensed under the terms of the GNU GPL, version 2.  See
   5  * the COPYING file in the top-level directory.
   6  *
   7  */
   8
   9 #include "qemu/osdep.h"
  10 #include "qemu-common.h"
  11 #include "xen-host-pci-device.h"
  12
  13 #define XEN_HOST_PCI_MAX_EXT_CAP \
  14     ((PCIE_CONFIG_SPACE_SIZE - PCI_CONFIG_SPACE_SIZE) / (PCI_CAP_SIZEOF + 4))
  15
  16 #ifdef XEN_HOST_PCI_DEVICE_DEBUG
  17 #  define XEN_HOST_PCI_LOG(f, a...) fprintf(stderr, "%s: " f, __func__, ##a)
  18 #else
  19 #  define XEN_HOST_PCI_LOG(f, a...) (void)0
  20 #endif
  21
  22 /*
  23  * from linux/ioport.h
  24  * IO resources have these defined flags.
  25  */
  26 #define IORESOURCE_BITS         0x000000ff      /* Bus-specific bits */
  27
  28 #define IORESOURCE_TYPE_BITS    0x00000f00      /* Resource type */
  29 #define IORESOURCE_IO           0x00000100
  30 #define IORESOURCE_MEM          0x00000200
  31
  32 #define IORESOURCE_PREFETCH     0x00001000      /* No side effects */
  33 #define IORESOURCE_MEM_64       0x00100000
  34
  35 static void xen_host_pci_sysfs_path(const XenHostPCIDevice *d,
  36                                     const char *name, char *buf, ssize_t size)
  37 {
  38     int rc;
  39
  40     rc = snprintf(buf, size, "/sys/bus/pci/devices/%04x:%02x:%02x.%d/%s",
  41                   d->domain, d->bus, d->dev, d->func, name);
  42     assert(rc >= 0 && rc < size);
  43 }
  44
  45
  46 /* This size should be enough to read the first 7 lines of a resource file */
  47 #define XEN_HOST_PCI_RESOURCE_BUFFER_SIZE 400
  48 static void xen_host_pci_get_resource(XenHostPCIDevice *d, Error **errp)
  49 {
  50     int i, rc, fd;
  51     char path[PATH_MAX];
  52     char buf[XEN_HOST_PCI_RESOURCE_BUFFER_SIZE];
  53     unsigned long long start, end, flags, size;
  54     char *endptr, *s;
  55     uint8_t type;
  56
  57     xen_host_pci_sysfs_path(d, "resource", path, sizeof(path));
  58
  59     fd = open(path, O_RDONLY);
  60     if (fd == -1) {
  61         error_setg_file_open(errp, errno, path);
  62         return;
  63     }
  64
  65     do {
  66         rc = read(fd, &buf, sizeof(buf) - 1);
  67         if (rc < 0 && errno != EINTR) {
  68             error_setg_errno(errp, errno, "read err");
  69             goto out;
  70         }
  71     } while (rc < 0);
  72     buf[rc] = 0;
  73
  74     s = buf;
  75     for (i = 0; i < PCI_NUM_REGIONS; i++) {
  76         type = 0;
  77
  78         start = strtoll(s, &endptr, 16);
  79         if (*endptr != ' ' || s == endptr) {
  80             break;
  81         }
  82         s = endptr + 1;
  83         end = strtoll(s, &endptr, 16);
  84         if (*endptr != ' ' || s == endptr) {
  85             break;
  86         }
  87         s = endptr + 1;
  88         flags = strtoll(s, &endptr, 16);
  89         if (*endptr != '\n' || s == endptr) {
  90             break;
  91         }
  92         s = endptr + 1;
  93
  94         if (start) {
  95             size = end - start + 1;
  96         } else {
  97             size = 0;
  98         }
  99
 100         if (flags & IORESOURCE_IO) {
 101             type |= XEN_HOST_PCI_REGION_TYPE_IO;
 102         }
 103         if (flags & IORESOURCE_MEM) {
 104             type |= XEN_HOST_PCI_REGION_TYPE_MEM;
 105         }
 106         if (flags & IORESOURCE_PREFETCH) {
 107             type |= XEN_HOST_PCI_REGION_TYPE_PREFETCH;
 108         }
 109         if (flags & IORESOURCE_MEM_64) {
 110             type |= XEN_HOST_PCI_REGION_TYPE_MEM_64;
 111         }
 112
 113         if (i < PCI_ROM_SLOT) {
 114             d->io_regions[i].base_addr = start;
 115             d->io_regions[i].size = size;
 116             d->io_regions[i].type = type;
 117             d->io_regions[i].bus_flags = flags & IORESOURCE_BITS;
 118         } else {
 119             d->rom.base_addr = start;
 120             d->rom.size = size;
 121             d->rom.type = type;
 122             d->rom.bus_flags = flags & IORESOURCE_BITS;
 123         }
 124     }
 125
 126     if (i != PCI_NUM_REGIONS) {
 127         error_setg(errp, "Invalid format or input too short: %s", buf);
 128     }
 129
 130 out:
 131     close(fd);
 132 }
 133
 134 /* This size should be enough to read a long from a file */
 135 #define XEN_HOST_PCI_GET_VALUE_BUFFER_SIZE 22
 136 static void xen_host_pci_get_value(XenHostPCIDevice *d, const char *name,
 137                                    unsigned int *pvalue, int base, Error **errp)
 138 {
 139     char path[PATH_MAX];
 140     char buf[XEN_HOST_PCI_GET_VALUE_BUFFER_SIZE];
 141     int fd, rc;
 142     unsigned long value;
 143     const char *endptr;
 144
 145     xen_host_pci_sysfs_path(d, name, path, sizeof(path));
 146
 147     fd = open(path, O_RDONLY);
 148     if (fd == -1) {
 149         error_setg_file_open(errp, errno, path);
 150         return;
 151     }
 152
 153     do {
 154         rc = read(fd, &buf, sizeof(buf) - 1);
 155         if (rc < 0 && errno != EINTR) {
 156             error_setg_errno(errp, errno, "read err");
 157             goto out;
 158         }
 159     } while (rc < 0);
 160
 161     buf[rc] = 0;
 162     rc = qemu_strtoul(buf, &endptr, base, &value);
 163     if (!rc) {
 164         assert(value <= UINT_MAX);
 165         *pvalue = value;
 166     } else {
 167         error_setg_errno(errp, -rc, "failed to parse value '%s'", buf);
 168     }
 169
 170 out:
 171     close(fd);
 172 }
 173
 174 static inline void xen_host_pci_get_hex_value(XenHostPCIDevice *d,
 175                                               const char *name,
 176                                               unsigned int *pvalue,
 177                                               Error **errp)
 178 {
 179     xen_host_pci_get_value(d, name, pvalue, 16, errp);
 180 }
 181
 182 static inline void xen_host_pci_get_dec_value(XenHostPCIDevice *d,
 183                                               const char *name,
 184                                               unsigned int *pvalue,
 185                                               Error **errp)
 186 {
 187     xen_host_pci_get_value(d, name, pvalue, 10, errp);
 188 }
 189
 190 static bool xen_host_pci_dev_is_virtfn(XenHostPCIDevice *d)
 191 {
 192     char path[PATH_MAX];
 193     struct stat buf;
 194
 195     xen_host_pci_sysfs_path(d, "physfn", path, sizeof(path));
 196
 197     return !stat(path, &buf);
 198 }
 199
 200 static void xen_host_pci_config_open(XenHostPCIDevice *d, Error **errp)
 201 {
 202     char path[PATH_MAX];
 203
 204     xen_host_pci_sysfs_path(d, "config", path, sizeof(path));
 205
 206     d->config_fd = open(path, O_RDWR);
 207     if (d->config_fd == -1) {
 208         error_setg_file_open(errp, errno, path);
 209     }
 210 }
 211
 212 static int xen_host_pci_config_read(XenHostPCIDevice *d,
 213                                     int pos, void *buf, int len)
 214 {
 215     int rc;
 216
 217     do {
 218         rc = pread(d->config_fd, buf, len, pos);
 219     } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
 220     if (rc != len) {
 221         return -errno;
 222     }
 223     return 0;
 224 }
 225
 226 static int xen_host_pci_config_write(XenHostPCIDevice *d,
 227                                      int pos, const void *buf, int len)
 228 {
 229     int rc;
 230
 231     do {
 232         rc = pwrite(d->config_fd, buf, len, pos);
 233     } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
 234     if (rc != len) {
 235         return -errno;
 236     }
 237     return 0;
 238 }
 239
 240
 241 int xen_host_pci_get_byte(XenHostPCIDevice *d, int pos, uint8_t *p)
 242 {
 243     uint8_t buf;
 244     int rc = xen_host_pci_config_read(d, pos, &buf, 1);
 245     if (!rc) {
 246         *p = buf;
 247     }
 248     return rc;
 249 }
 250
 251 int xen_host_pci_get_word(XenHostPCIDevice *d, int pos, uint16_t *p)
 252 {
 253     uint16_t buf;
 254     int rc = xen_host_pci_config_read(d, pos, &buf, 2);
 255     if (!rc) {
 256         *p = le16_to_cpu(buf);
 257     }
 258     return rc;
 259 }
 260
 261 int xen_host_pci_get_long(XenHostPCIDevice *d, int pos, uint32_t *p)
 262 {
 263     uint32_t buf;
 264     int rc = xen_host_pci_config_read(d, pos, &buf, 4);
 265     if (!rc) {
 266         *p = le32_to_cpu(buf);
 267     }
 268     return rc;
 269 }
 270
 271 int xen_host_pci_get_block(XenHostPCIDevice *d, int pos, uint8_t *buf, int len)
 272 {
 273     return xen_host_pci_config_read(d, pos, buf, len);
 274 }
 275
 276 int xen_host_pci_set_byte(XenHostPCIDevice *d, int pos, uint8_t data)
 277 {
 278     return xen_host_pci_config_write(d, pos, &data, 1);
 279 }
 280
 281 int xen_host_pci_set_word(XenHostPCIDevice *d, int pos, uint16_t data)
 282 {
 283     data = cpu_to_le16(data);
 284     return xen_host_pci_config_write(d, pos, &data, 2);
 285 }
 286
 287 int xen_host_pci_set_long(XenHostPCIDevice *d, int pos, uint32_t data)
 288 {
 289     data = cpu_to_le32(data);
 290     return xen_host_pci_config_write(d, pos, &data, 4);
 291 }
 292
 293 int xen_host_pci_set_block(XenHostPCIDevice *d, int pos, uint8_t *buf, int len)
 294 {
 295     return xen_host_pci_config_write(d, pos, buf, len);
 296 }
 297
 298 int xen_host_pci_find_ext_cap_offset(XenHostPCIDevice *d, uint32_t cap)
 299 {
 300     uint32_t header = 0;
 301     int max_cap = XEN_HOST_PCI_MAX_EXT_CAP;
 302     int pos = PCI_CONFIG_SPACE_SIZE;
 303
 304     do {
 305         if (xen_host_pci_get_long(d, pos, &header)) {
 306             break;
 307         }
 308         /*
 309          * If we have no capabilities, this is indicated by cap ID,
 310          * cap version and next pointer all being 0.
 311          */
 312         if (header == 0) {
 313             break;
 314         }
 315
 316         if (PCI_EXT_CAP_ID(header) == cap) {
 317             return pos;
 318         }
 319
 320         pos = PCI_EXT_CAP_NEXT(header);
 321         if (pos < PCI_CONFIG_SPACE_SIZE) {
 322             break;
 323         }
 324
 325         max_cap--;
 326     } while (max_cap > 0);
 327
 328     return -1;
 329 }
 330
 331 void xen_host_pci_device_get(XenHostPCIDevice *d, uint16_t domain,
 332                              uint8_t bus, uint8_t dev, uint8_t func,
 333                              Error **errp)
 334 {
 335     unsigned int v;
 336     Error *err = NULL;
 337
 338     d->config_fd = -1;
 339     d->domain = domain;
 340     d->bus = bus;
 341     d->dev = dev;
 342     d->func = func;
 343
 344     xen_host_pci_config_open(d, &err);
 345     if (err) {
 346         goto error;
 347     }
 348
 349     xen_host_pci_get_resource(d, &err);
 350     if (err) {
 351         goto error;
 352     }
 353
 354     xen_host_pci_get_hex_value(d, "vendor", &v, &err);
 355     if (err) {
 356         goto error;
 357     }
 358     d->vendor_id = v;
 359
 360     xen_host_pci_get_hex_value(d, "device", &v, &err);
 361     if (err) {
 362         goto error;
 363     }
 364     d->device_id = v;
 365
 366     xen_host_pci_get_dec_value(d, "irq", &v, &err);
 367     if (err) {
 368         goto error;
 369     }
 370     d->irq = v;
 371
 372     xen_host_pci_get_hex_value(d, "class", &v, &err);
 373     if (err) {
 374         goto error;
 375     }
 376     d->class_code = v;
 377
 378     d->is_virtfn = xen_host_pci_dev_is_virtfn(d);
 379
 380     return;
 381
 382 error:
 383     error_propagate(errp, err);
 384
 385     if (d->config_fd >= 0) {
 386         close(d->config_fd);
 387         d->config_fd = -1;
 388     }
 389 }
 390
 391 bool xen_host_pci_device_closed(XenHostPCIDevice *d)
 392 {
 393     return d->config_fd == -1;
 394 }
 395
 396 void xen_host_pci_device_put(XenHostPCIDevice *d)
 397 {
 398     if (d->config_fd >= 0) {
 399         close(d->config_fd);
 400         d->config_fd = -1;
 401     }
 402 }