source: rtems/c/src/lib/libbsp/powerpc/shared/pci/pcifinddevice.c @ 0943f48d

/* Author: Till Straumann <strauman@slac.stanford.edu>, 2001 */

/* find a particular PCI device
 * (we assume, the firmware configured the PCI bus[es] for us)
 *
 * $Id$
 */

#define PCI_INVALID_VENDORDEVICEID  0xffffffff
#define PCI_MULTI_FUNCTION      0x80

#include <bsp/pci.h>
#include <rtems/bspIo.h>

int
pci_find_device(
  unsigned short vendorid,
  unsigned short deviceid,
  int instance,
  int *pbus,
  int *pdev,
  int *pfun
) {
   unsigned int d;
   unsigned short s;
   unsigned char bus,dev,fun,hd;

   for (bus=0; bus<BusCountPCI(); bus++) {
     for (dev=0; dev<PCI_MAX_DEVICES; dev++) {

       pci_read_config_byte(bus,dev,0, PCI_HEADER_TYPE, &hd);
       hd = (hd & PCI_MULTI_FUNCTION ? PCI_MAX_FUNCTIONS : 1);

       for (fun=0; fun<hd; fun++) {
         /*
          * The last devfn id/slot is special; must skip it
          */
        if (PCI_MAX_DEVICES-1==dev && PCI_MAX_FUNCTIONS-1 == fun)
          break;
        (void)pci_read_config_dword(bus,dev,fun,PCI_VENDOR_ID,&d);
        if (PCI_INVALID_VENDORDEVICEID == d)
          continue;
#ifdef PCI_DEBUG
        printk("pci_find_by_devid: found 0x%08x at %d/%d/%d\n",d,bus,dev,fun);
#endif
        (void) pci_read_config_word(bus,dev,fun,PCI_VENDOR_ID,&s);
        if (vendorid != s)
          continue;
        (void) pci_read_config_word(bus,dev,fun,PCI_DEVICE_ID,&s);
        if (deviceid == s) {
          if (instance--) continue;
          *pbus=bus; *pdev=dev; *pfun=fun;
          return 0;
        }
      }
    }
  }
  return -1;
}