pci: Add a function to find a device by class
[platform/kernel/u-boot.git] / drivers / pci / pci.c
index 950a247..e1296ca 100644 (file)
@@ -15,6 +15,7 @@
 #include <common.h>
 
 #include <command.h>
+#include <errno.h>
 #include <asm/processor.h>
 #include <asm/io.h>
 #include <pci.h>
@@ -236,6 +237,48 @@ pci_dev_t pci_find_devices(struct pci_device_id *ids, int index)
        return -1;
 }
 
+pci_dev_t pci_find_class(uint find_class, int index)
+{
+       int bus;
+       int devnum;
+       pci_dev_t bdf;
+       uint32_t class;
+
+       for (bus = 0; bus <= pci_last_busno(); bus++) {
+               for (devnum = 0; devnum < PCI_MAX_PCI_DEVICES - 1; devnum++) {
+                       pci_read_config_dword(PCI_BDF(bus, devnum, 0),
+                                             PCI_CLASS_REVISION, &class);
+                       if (class >> 16 == 0xffff)
+                               continue;
+
+                       for (bdf = PCI_BDF(bus, devnum, 0);
+                                       bdf <= PCI_BDF(bus, devnum,
+                                               PCI_MAX_PCI_FUNCTIONS - 1);
+                                       bdf += PCI_BDF(0, 0, 1)) {
+                               pci_read_config_dword(bdf, PCI_CLASS_REVISION,
+                                                     &class);
+                               class >>= 8;
+
+                               if (class != find_class)
+                                       continue;
+                               /*
+                                * Decrement the index. We want to return the
+                                * correct device, so index is 0 for the first
+                                * matching device, 1 for the second, etc.
+                                */
+                               if (index) {
+                                       index--;
+                                       continue;
+                               }
+                               /* Return index'th controller. */
+                               return bdf;
+                       }
+               }
+       }
+
+       return -ENODEV;
+}
+
 pci_dev_t pci_find_device(unsigned int vendor, unsigned int device, int index)
 {
        struct pci_device_id ids[2] = { {}, {0, 0} };