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-common.h"
  10 #include "xen-host-pci-device.h"
  11
  12 #define XEN_HOST_PCI_MAX_EXT_CAP \
  13     ((PCIE_CONFIG_SPACE_SIZE - PCI_CONFIG_SPACE_SIZE) / (PCI_CAP_SIZEOF + 4))
  14
  15 #ifdef XEN_HOST_PCI_DEVICE_DEBUG
  16 #  define XEN_HOST_PCI_LOG(f, a...) fprintf(stderr, "%s: " f, __func__, ##a)
  17 #else
  18 #  define XEN_HOST_PCI_LOG(f, a...) (void)0
  19 #endif
  20
  21 /*
  22  * from linux/ioport.h
  23  * IO resources have these defined flags.
  24  */
  25 #define IORESOURCE_BITS         0x000000ff      /* Bus-specific bits */
  26
  27 #define IORESOURCE_TYPE_BITS    0x00000f00      /* Resource type */
  28 #define IORESOURCE_IO           0x00000100
  29 #define IORESOURCE_MEM          0x00000200
  30
  31 #define IORESOURCE_PREFETCH     0x00001000      /* No side effects */
  32 #define IORESOURCE_MEM_64       0x00100000
  33
  34 static void xen_host_pci_sysfs_path(const XenHostPCIDevice *d,
  35                                     const char *name, char *buf, ssize_t size)
  36 {
  37     int rc;
  38
  39     rc = snprintf(buf, size, "/sys/bus/pci/devices/%04x:%02x:%02x.%d/%s",
  40                   d->domain, d->bus, d->dev, d->func, name);
  41     assert(rc >= 0 && rc < size);
  42 }
  43
  44
  45 /* This size should be enough to read the first 7 lines of a resource file */
  46 #define XEN_HOST_PCI_RESOURCE_BUFFER_SIZE 400
  47 static int xen_host_pci_get_resource(XenHostPCIDevice *d)
  48 {
  49     int i, rc, fd;
  50     char path[PATH_MAX];
  51     char buf[XEN_HOST_PCI_RESOURCE_BUFFER_SIZE];
  52     unsigned long long start, end, flags, size;
  53     char *endptr, *s;
  54     uint8_t type;
  55
  56     xen_host_pci_sysfs_path(d, "resource", path, sizeof(path));
  57
  58     fd = open(path, O_RDONLY);
  59     if (fd == -1) {
  60         XEN_HOST_PCI_LOG("Error: Can't open %s: %s\n", path, strerror(errno));
  61         return -errno;
  62     }
  63
  64     do {
  65         rc = read(fd, &buf, sizeof (buf) - 1);
  66         if (rc < 0 && errno != EINTR) {
  67             rc = -errno;
  68             goto out;
  69         }
  70     } while (rc < 0);
  71     buf[rc] = 0;
  72     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     if (i != PCI_NUM_REGIONS) {
 126         /* Invalid format or input to short */
 127         rc = -ENODEV;
 128     }
 129
 130 out:
 131     close(fd);
 132     return rc;
 133 }
 134
 135 /* This size should be enough to read a long from a file */
 136 #define XEN_HOST_PCI_GET_VALUE_BUFFER_SIZE 22
 137 static int xen_host_pci_get_value(XenHostPCIDevice *d, const char *name,
 138                                   unsigned int *pvalue, int base)
 139 {
 140     char path[PATH_MAX];
 141     char buf[XEN_HOST_PCI_GET_VALUE_BUFFER_SIZE];
 142     int fd, rc;
 143     unsigned long value;
 144     char *endptr;
 145
 146     xen_host_pci_sysfs_path(d, name, path, sizeof(path));
 147
 148     fd = open(path, O_RDONLY);
 149     if (fd == -1) {
 150         XEN_HOST_PCI_LOG("Error: Can't open %s: %s\n", path, strerror(errno));
 151         return -errno;
 152     }
 153     do {
 154         rc = read(fd, &buf, sizeof (buf) - 1);
 155         if (rc < 0 && errno != EINTR) {
 156             rc = -errno;
 157             goto out;
 158         }
 159     } while (rc < 0);
 160     buf[rc] = 0;
 161     value = strtol(buf, &endptr, base);
 162     if (endptr == buf || *endptr != '\n') {
 163         rc = -1;
 164     } else if ((value == LONG_MIN || value == LONG_MAX) && errno == ERANGE) {
 165         rc = -errno;
 166     } else {
 167         rc = 0;
 168         *pvalue = value;
 169     }
 170 out:
 171     close(fd);
 172     return rc;
 173 }
 174
 175 static inline int xen_host_pci_get_hex_value(XenHostPCIDevice *d,
 176                                              const char *name,
 177                                              unsigned int *pvalue)
 178 {
 179     return xen_host_pci_get_value(d, name, pvalue, 16);
 180 }
 181
 182 static inline int xen_host_pci_get_dec_value(XenHostPCIDevice *d,
 183                                              const char *name,
 184                                              unsigned int *pvalue)
 185 {
 186     return xen_host_pci_get_value(d, name, pvalue, 10);
 187 }
 188
 189 static bool xen_host_pci_dev_is_virtfn(XenHostPCIDevice *d)
 190 {
 191     char path[PATH_MAX];
 192     struct stat buf;
 193
 194     xen_host_pci_sysfs_path(d, "physfn", path, sizeof(path));
 195
 196     return !stat(path, &buf);
 197 }
 198
 199 static int xen_host_pci_config_open(XenHostPCIDevice *d)
 200 {
 201     char path[PATH_MAX];
 202
 203     xen_host_pci_sysfs_path(d, "config", path, sizeof(path));
 204
 205     d->config_fd = open(path, O_RDWR);
 206     if (d->config_fd < 0) {
 207         return -errno;
 208     }
 209     return 0;
 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 int xen_host_pci_device_get(XenHostPCIDevice *d, uint16_t domain,
 332                             uint8_t bus, uint8_t dev, uint8_t func)
 333 {
 334     unsigned int v;
 335     int rc = 0;
 336
 337     d->config_fd = -1;
 338     d->domain = domain;
 339     d->bus = bus;
 340     d->dev = dev;
 341     d->func = func;
 342
 343     rc = xen_host_pci_config_open(d);
 344     if (rc) {
 345         goto error;
 346     }
 347     rc = xen_host_pci_get_resource(d);
 348     if (rc) {
 349         goto error;
 350     }
 351     rc = xen_host_pci_get_hex_value(d, "vendor", &v);
 352     if (rc) {
 353         goto error;
 354     }
 355     d->vendor_id = v;
 356     rc = xen_host_pci_get_hex_value(d, "device", &v);
 357     if (rc) {
 358         goto error;
 359     }
 360     d->device_id = v;
 361     rc = xen_host_pci_get_dec_value(d, "irq", &v);
 362     if (rc) {
 363         goto error;
 364     }
 365     d->irq = v;
 366     rc = xen_host_pci_get_hex_value(d, "class", &v);
 367     if (rc) {
 368         goto error;
 369     }
 370     d->class_code = v;
 371     d->is_virtfn = xen_host_pci_dev_is_virtfn(d);
 372
 373     return 0;
 374 error:
 375     if (d->config_fd >= 0) {
 376         close(d->config_fd);
 377         d->config_fd = -1;
 378     }
 379     return rc;
 380 }
 381
 382 bool xen_host_pci_device_closed(XenHostPCIDevice *d)
 383 {
 384     return d->config_fd == -1;
 385 }
 386
 387 void xen_host_pci_device_put(XenHostPCIDevice *d)
 388 {
 389     if (d->config_fd >= 0) {
 390         close(d->config_fd);
 391         d->config_fd = -1;
 392     }
 393 }