Archipelago » qemu

/*

 * Copyright (C) 2011       Citrix Ltd.

 *

 * This work is licensed under the terms of the GNU GPL, version 2.  See

 * the COPYING file in the top-level directory.

 *

 */

#include "qemu-common.h"

#include "xen-host-pci-device.h"

#define XEN_HOST_PCI_MAX_EXT_CAP \

    ((PCIE_CONFIG_SPACE_SIZE - PCI_CONFIG_SPACE_SIZE) / (PCI_CAP_SIZEOF + 4))

#ifdef XEN_HOST_PCI_DEVICE_DEBUG

#  define XEN_HOST_PCI_LOG(f, a...) fprintf(stderr, "%s: " f, __func__, ##a)

#else

#  define XEN_HOST_PCI_LOG(f, a...) (void)0

#endif

/*

 * from linux/ioport.h

 * IO resources have these defined flags.

 */

#define IORESOURCE_BITS         0x000000ff      /* Bus-specific bits */

#define IORESOURCE_TYPE_BITS    0x00000f00      /* Resource type */

#define IORESOURCE_IO           0x00000100

#define IORESOURCE_MEM          0x00000200

#define IORESOURCE_PREFETCH     0x00001000      /* No side effects */

#define IORESOURCE_MEM_64       0x00100000

static int xen_host_pci_sysfs_path(const XenHostPCIDevice *d,

                                   const char *name, char *buf, ssize_t size)

{

    int rc;

    rc = snprintf(buf, size, "/sys/bus/pci/devices/%04x:%02x:%02x.%d/%s",

                  d->domain, d->bus, d->dev, d->func, name);

    if (rc >= size || rc < 0) {

        /* The ouput is truncated or an other error is encountered */

        return -ENODEV;

    }

    return 0;

}

/* This size should be enough to read the first 7 lines of a ressource file */

#define XEN_HOST_PCI_RESSOURCE_BUFFER_SIZE 400

static int xen_host_pci_get_resource(XenHostPCIDevice *d)

{

    int i, rc, fd;

    char path[PATH_MAX];

    char buf[XEN_HOST_PCI_RESSOURCE_BUFFER_SIZE];

    unsigned long long start, end, flags, size;

    char *endptr, *s;

    uint8_t type;

    rc = xen_host_pci_sysfs_path(d, "resource", path, sizeof (path));

    if (rc) {

        return rc;

    }

    fd = open(path, O_RDONLY);

    if (fd == -1) {

        XEN_HOST_PCI_LOG("Error: Can't open %s: %s\n", path, strerror(errno));

        return -errno;

    }

    do {

        rc = read(fd, &buf, sizeof (buf) - 1);

        if (rc < 0 && errno != EINTR) {

            rc = -errno;

            goto out;

        }

    } while (rc < 0);

    buf[rc] = 0;

    rc = 0;

    s = buf;

    for (i = 0; i < PCI_NUM_REGIONS; i++) {

        type = 0;

        start = strtoll(s, &endptr, 16);

        if (*endptr != ' ' || s == endptr) {

            break;

        }

        s = endptr + 1;

        end = strtoll(s, &endptr, 16);

        if (*endptr != ' ' || s == endptr) {

            break;

        }

        s = endptr + 1;

        flags = strtoll(s, &endptr, 16);

        if (*endptr != '\n' || s == endptr) {

            break;

        }

        s = endptr + 1;

        if (start) {

            size = end - start + 1;

        } else {

            size = 0;

        }

        if (flags & IORESOURCE_IO) {

            type |= XEN_HOST_PCI_REGION_TYPE_IO;

        }

        if (flags & IORESOURCE_MEM) {

            type |= XEN_HOST_PCI_REGION_TYPE_MEM;

        }

        if (flags & IORESOURCE_PREFETCH) {

            type |= XEN_HOST_PCI_REGION_TYPE_PREFETCH;

        }

        if (flags & IORESOURCE_MEM_64) {

            type |= XEN_HOST_PCI_REGION_TYPE_MEM_64;

        }

        if (i < PCI_ROM_SLOT) {

            d->io_regions[i].base_addr = start;

            d->io_regions[i].size = size;

            d->io_regions[i].type = type;

            d->io_regions[i].bus_flags = flags & IORESOURCE_BITS;

        } else {

            d->rom.base_addr = start;

            d->rom.size = size;

            d->rom.type = type;

            d->rom.bus_flags = flags & IORESOURCE_BITS;

        }

    }

    if (i != PCI_NUM_REGIONS) {

        /* Invalid format or input to short */

        rc = -ENODEV;

    }

out:

    close(fd);

    return rc;

}

/* This size should be enough to read a long from a file */

#define XEN_HOST_PCI_GET_VALUE_BUFFER_SIZE 22

static int xen_host_pci_get_value(XenHostPCIDevice *d, const char *name,

                                  unsigned int *pvalue, int base)

{

    char path[PATH_MAX];

    char buf[XEN_HOST_PCI_GET_VALUE_BUFFER_SIZE];

    int fd, rc;

    unsigned long value;

    char *endptr;

    rc = xen_host_pci_sysfs_path(d, name, path, sizeof (path));

    if (rc) {

        return rc;

    }

    fd = open(path, O_RDONLY);

    if (fd == -1) {

        XEN_HOST_PCI_LOG("Error: Can't open %s: %s\n", path, strerror(errno));

        return -errno;

    }

    do {

        rc = read(fd, &buf, sizeof (buf) - 1);

        if (rc < 0 && errno != EINTR) {

            rc = -errno;

            goto out;

        }

    } while (rc < 0);

    buf[rc] = 0;

    value = strtol(buf, &endptr, base);

    if (endptr == buf || *endptr != '\n') {

        rc = -1;

    } else if ((value == LONG_MIN || value == LONG_MAX) && errno == ERANGE) {

        rc = -errno;

    } else {

        rc = 0;

        *pvalue = value;

    }

out:

    close(fd);

    return rc;

}

static inline int xen_host_pci_get_hex_value(XenHostPCIDevice *d,

                                             const char *name,

                                             unsigned int *pvalue)

{

    return xen_host_pci_get_value(d, name, pvalue, 16);

}

static inline int xen_host_pci_get_dec_value(XenHostPCIDevice *d,

                                             const char *name,

                                             unsigned int *pvalue)

{

    return xen_host_pci_get_value(d, name, pvalue, 10);

}

static bool xen_host_pci_dev_is_virtfn(XenHostPCIDevice *d)

{

    char path[PATH_MAX];

    struct stat buf;

    if (xen_host_pci_sysfs_path(d, "physfn", path, sizeof (path))) {

        return false;

    }

    return !stat(path, &buf);

}

static int xen_host_pci_config_open(XenHostPCIDevice *d)

{

    char path[PATH_MAX];

    int rc;

    rc = xen_host_pci_sysfs_path(d, "config", path, sizeof (path));

    if (rc) {

        return rc;

    }

    d->config_fd = open(path, O_RDWR);

    if (d->config_fd < 0) {

        return -errno;

    }

    return 0;

}

static int xen_host_pci_config_read(XenHostPCIDevice *d,

                                    int pos, void *buf, int len)

{

    int rc;

    do {

        rc = pread(d->config_fd, buf, len, pos);

    } while (rc < 0 && (errno == EINTR || errno == EAGAIN));

    if (rc != len) {

        return -errno;

    }

    return 0;

}

static int xen_host_pci_config_write(XenHostPCIDevice *d,

                                     int pos, const void *buf, int len)

{

    int rc;

    do {

        rc = pwrite(d->config_fd, buf, len, pos);

    } while (rc < 0 && (errno == EINTR || errno == EAGAIN));

    if (rc != len) {

        return -errno;

    }

    return 0;

}

int xen_host_pci_get_byte(XenHostPCIDevice *d, int pos, uint8_t *p)

{

    uint8_t buf;

    int rc = xen_host_pci_config_read(d, pos, &buf, 1);

    if (!rc) {

        *p = buf;

    }

    return rc;

}

int xen_host_pci_get_word(XenHostPCIDevice *d, int pos, uint16_t *p)

{

    uint16_t buf;

    int rc = xen_host_pci_config_read(d, pos, &buf, 2);

    if (!rc) {

        *p = le16_to_cpu(buf);

    }

    return rc;

}

int xen_host_pci_get_long(XenHostPCIDevice *d, int pos, uint32_t *p)

{

    uint32_t buf;

    int rc = xen_host_pci_config_read(d, pos, &buf, 4);

    if (!rc) {

        *p = le32_to_cpu(buf);

    }

    return rc;

}

int xen_host_pci_get_block(XenHostPCIDevice *d, int pos, uint8_t *buf, int len)

{

    return xen_host_pci_config_read(d, pos, buf, len);

}

int xen_host_pci_set_byte(XenHostPCIDevice *d, int pos, uint8_t data)

{

    return xen_host_pci_config_write(d, pos, &data, 1);

}

int xen_host_pci_set_word(XenHostPCIDevice *d, int pos, uint16_t data)

{

    data = cpu_to_le16(data);

    return xen_host_pci_config_write(d, pos, &data, 2);

}

int xen_host_pci_set_long(XenHostPCIDevice *d, int pos, uint32_t data)

{

    data = cpu_to_le32(data);

    return xen_host_pci_config_write(d, pos, &data, 4);

}

int xen_host_pci_set_block(XenHostPCIDevice *d, int pos, uint8_t *buf, int len)

{

    return xen_host_pci_config_write(d, pos, buf, len);

}

int xen_host_pci_find_ext_cap_offset(XenHostPCIDevice *d, uint32_t cap)

{

    uint32_t header = 0;

    int max_cap = XEN_HOST_PCI_MAX_EXT_CAP;

    int pos = PCI_CONFIG_SPACE_SIZE;

    do {

        if (xen_host_pci_get_long(d, pos, &header)) {

            break;

        }

        /*

         * If we have no capabilities, this is indicated by cap ID,

         * cap version and next pointer all being 0.

         */

        if (header == 0) {

            break;

        }

        if (PCI_EXT_CAP_ID(header) == cap) {

            return pos;

        }

        pos = PCI_EXT_CAP_NEXT(header);

        if (pos < PCI_CONFIG_SPACE_SIZE) {

            break;

        }

        max_cap--;

    } while (max_cap > 0);

    return -1;

}

int xen_host_pci_device_get(XenHostPCIDevice *d, uint16_t domain,

                            uint8_t bus, uint8_t dev, uint8_t func)

{

    unsigned int v;

    int rc = 0;

    d->config_fd = -1;

    d->domain = domain;

    d->bus = bus;

    d->dev = dev;

    d->func = func;

    rc = xen_host_pci_config_open(d);

    if (rc) {

        goto error;

    }

    rc = xen_host_pci_get_resource(d);

    if (rc) {

        goto error;

    }

    rc = xen_host_pci_get_hex_value(d, "vendor", &v);

    if (rc) {

        goto error;

    }

    d->vendor_id = v;

    rc = xen_host_pci_get_hex_value(d, "device", &v);

    if (rc) {

        goto error;

    }

    d->device_id = v;

    rc = xen_host_pci_get_dec_value(d, "irq", &v);

    if (rc) {

        goto error;

    }

    d->irq = v;

    d->is_virtfn = xen_host_pci_dev_is_virtfn(d);

    return 0;

error:

    if (d->config_fd >= 0) {

        close(d->config_fd);

        d->config_fd = -1;

    }

    return rc;

}

void xen_host_pci_device_put(XenHostPCIDevice *d)

{

    if (d->config_fd >= 0) {

        close(d->config_fd);

        d->config_fd = -1;

    }

}