source: rtems/cpukit/libpci/pci_for_each.c @ 02550220

/*  PCI Help Function, iterate over all PCI devices. Find devices by cfg access.
 *
 *  COPYRIGHT (c) 2010.
 *  Cobham Gaisler AB.
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.rtems.com/license/LICENSE.
 */

#include <pci.h>
#include <pci/access.h>

/*#define DEBUG*/

#ifdef DEBUG
#include <rtems/bspIo.h>
#define DBG(args...) printk(args)
#else
#define DBG(args...)
#endif

int pci_for_each(int (*func)(pci_dev_t, void*), void *arg)
{
        uint32_t id;
        uint8_t hd;
        int bus, dev, fun, result, fail;
        int maxbus = pci_bus_count();
        pci_dev_t pcidev;

        for (bus = 0; bus < maxbus ; bus++) {
                for (dev = 0; dev < PCI_MAX_DEVICES; dev++) {
                        pcidev = PCI_DEV(bus, dev, 0);

                        for (fun = 0; fun < PCI_MAX_FUNCTIONS; fun++, pcidev++) {
                                fail = pci_cfg_r32(pcidev, PCI_VENDOR_ID, &id);
                                if (fail || (0xffffffff == id) || (0 == id)) {
                                        if (fun == 0)
                                                break;
                                        else
                                                continue;
                                }

                                DBG("pcibus_for_each: found 0x%08lx at"
                                    " %d/%d/%d\n", id, bus, dev, fun);
                                result = func(pcidev, arg);
                                if (result != 0)
                                        return result; /* Stopped */

                                /* Stop if not a multi-function device */
                                if (fun == 0) {
                                        pci_cfg_r8(pcidev, PCI_HEADER_TYPE,
                                                        &hd);
                                        if ((hd & PCI_MULTI_FUNCTION) == 0)
                                                break;
                                }
                        }
                }
        }

        return 0; /* scanned all */
}