pci: add the prog-if (register level programming interface) to pci de…

…vice attributes

It's the 3rd byte of the class, useful in some corner cases.

It'll be assumed 0 when importing from pre-3.x XMLs.

Signed-off-by: Brice Goglin <Brice.Goglin@inria.fr>

NEWS

@@ -21,6 +21,8 @@ Version 3.0.0
 -------------
 * API
   + PCI domains are now always 32bits.
+  + The "programming interface" of PCI devices is now exposed
+    in PCI object attributes.
 
 
 Version 2.9.0

hwloc/topology-linux.c

@@ -6864,6 +6864,7 @@ hwloc_linuxfs_pci_look_pcidevices(struct hwloc_backend *backend)
     unsigned domain, bus, dev, func;
     unsigned secondary_bus, subordinate_bus;
     unsigned short class_id;
+    unsigned char prog_if;
     hwloc_obj_type_t type;
     hwloc_obj_t obj;
     struct hwloc_pcidev_attr_s *attr;
@@ -6884,10 +6885,14 @@ hwloc_linuxfs_pci_look_pcidevices(struct hwloc_backend *backend)
     }
 
     class_id = HWLOC_PCI_CLASS_NOT_DEFINED;
+    prog_if = 0;
     err = snprintf(path, sizeof(path), "/sys/bus/pci/devices/%s/class", dirent->d_name);
     if ((size_t) err < sizeof(path)
-	&& hwloc_read_path_by_length(path, value, sizeof(value), root_fd) > 0)
-      class_id = strtoul(value, NULL, 16) >> 8;
+	&& hwloc_read_path_by_length(path, value, sizeof(value), root_fd) > 0) {
+      unsigned long fullclass = strtoul(value, NULL, 16);
+      class_id = fullclass >> 8;
+      prog_if = fullclass & 0xff;
+    }
 
     type = hwloc_pcidisc_check_bridge_type(class_id, config_space_cache);
     /* only HWLOC_OBJ_BRIDGE for bridges to-PCI */
@@ -6943,6 +6948,7 @@ hwloc_linuxfs_pci_look_pcidevices(struct hwloc_backend *backend)
     attr->vendor_id = 0;
     attr->device_id = 0;
     attr->class_id = class_id;
+    attr->prog_if = prog_if;
     attr->revision = 0;
     attr->subvendor_id = 0;
     attr->subdevice_id = 0;

hwloc/topology-nvml.c

@@ -90,9 +90,9 @@ hwloc__nvml_get_peer_obj_by_pci(struct hwloc_topology *topology, hwloc_obj_t gpu
   default: {
     static int warned = 0;
     if (!warned && HWLOC_SHOW_ALL_ERRORS())
-      fprintf(stderr, "hwloc failed to recognize NVLink peer %04x:%02x:%02x class %04x vendor %04x device %04x\n",
+      fprintf(stderr, "hwloc failed to recognize NVLink peer %04x:%02x:%02x class %04x prog-if %02x vendor %04x device %04x\n",
               peer_bdf.domain, peer_bdf.bus, peer_bdf.device,
-              obj->attr->pcidev.class_id, obj->attr->pcidev.vendor_id, obj->attr->pcidev.device_id);
+              obj->attr->pcidev.class_id, obj->attr->pcidev.prog_if, obj->attr->pcidev.vendor_id, obj->attr->pcidev.device_id);
     warned = 1;
     return NULL;
   }

hwloc/topology-pci.c

@@ -193,7 +193,7 @@ hwloc_look_pci(struct hwloc_backend *backend, struct hwloc_disc_status *dstatus)
     struct hwloc_obj *obj;
     unsigned domain, bus, dev, func;
     unsigned secondary_bus, subordinate_bus;
-    unsigned device_class;
+    unsigned device_class, prog_if;
     unsigned short tmp16;
     unsigned offset;
 
@@ -209,6 +209,7 @@ hwloc_look_pci(struct hwloc_backend *backend, struct hwloc_disc_status *dstatus)
 
     /* try to read the device_class */
     device_class = pcidev->device_class >> 8;
+    prog_if = pcidev->device_class & 0xff;
 
     /* bridge or pci dev? */
     type = hwloc_pcidisc_check_bridge_type(device_class, config_space_cache);
@@ -297,6 +298,7 @@ hwloc_look_pci(struct hwloc_backend *backend, struct hwloc_disc_status *dstatus)
     obj->attr->pcidev.vendor_id = pcidev->vendor_id;
     obj->attr->pcidev.device_id = pcidev->device_id;
     obj->attr->pcidev.class_id = device_class;
+    obj->attr->pcidev.prog_if = prog_if;
     obj->attr->pcidev.revision = config_space_cache[PCI_REVISION_ID];
 
     /* bridge specific attributes */
@@ -358,9 +360,9 @@ hwloc_look_pci(struct hwloc_backend *backend, struct hwloc_disc_status *dstatus)
        */
     }
 
-    hwloc_debug("  %04x:%02x:%02x.%01x %04x %04x:%04x\n",
+    hwloc_debug("  %04x:%02x:%02x.%01x %04x %02x %04x:%04x\n",
 		domain, bus, dev, func,
-		device_class, pcidev->vendor_id, pcidev->device_id);
+		device_class, prog_if, pcidev->vendor_id, pcidev->device_id);
 
     hwloc_pci_get_obj_names(obj, &m);
     hwloc_pcidisc_tree_insert_by_busid(&tree, obj);

hwloc/topology-xml.c

@@ -291,14 +291,17 @@ hwloc__xml_import_object_attr(struct hwloc_topology *topology,
     switch (obj->type) {
     case HWLOC_OBJ_PCI_DEVICE:
     case HWLOC_OBJ_BRIDGE: {
-      unsigned classid, vendor, device, subvendor, subdevice, revision;
-      if (sscanf(value, "%x [%04x:%04x] [%04x:%04x] %02x",
-		 &classid, &vendor, &device, &subvendor, &subdevice, &revision) != 6) {
+      unsigned classid, vendor, device, subvendor, subdevice, revision, prog_if = 0;
+      if (sscanf(value, "%x [%04x:%04x] [%04x:%04x] %02x %02x",
+		 &classid, &vendor, &device, &subvendor, &subdevice, &revision, &prog_if) != 7
+          && sscanf(value, "%x [%04x:%04x] [%04x:%04x] %02x", /* hwloc < 3.x didn't export the prog-if */
+                    &classid, &vendor, &device, &subvendor, &subdevice, &revision) != 6) {
 	if (hwloc__xml_verbose())
 	  fprintf(stderr, "%s: ignoring invalid pci_type format string %s\n",
 		  state->global->msgprefix, value);
       } else {
 	obj->attr->pcidev.class_id = classid;
+	obj->attr->pcidev.prog_if = prog_if;
 	obj->attr->pcidev.vendor_id = vendor;
 	obj->attr->pcidev.device_id = device;
 	obj->attr->pcidev.subvendor_id = subvendor;
@@ -2586,11 +2589,11 @@ hwloc__xml_export_object_contents (hwloc__xml_export_state_t state, hwloc_topolo
 	    (unsigned) obj->attr->pcidev.dev,
 	    (unsigned) obj->attr->pcidev.func);
     state->new_prop(state, "pci_busid", tmp);
-    sprintf(tmp, "%04x [%04x:%04x] [%04x:%04x] %02x",
+    sprintf(tmp, "%04x [%04x:%04x] [%04x:%04x] %02x %02x",
 	    (unsigned) obj->attr->pcidev.class_id,
 	    (unsigned) obj->attr->pcidev.vendor_id, (unsigned) obj->attr->pcidev.device_id,
 	    (unsigned) obj->attr->pcidev.subvendor_id, (unsigned) obj->attr->pcidev.subdevice_id,
-	    (unsigned) obj->attr->pcidev.revision);
+	    (unsigned) obj->attr->pcidev.revision, (unsigned) obj->attr->pcidev.prog_if);
     state->new_prop(state, "pci_type", tmp);
     sprintf(tmp, "%f", obj->attr->pcidev.linkspeed);
     state->new_prop(state, "pci_link_speed", tmp);

include/hwloc.h

@@ -93,7 +93,7 @@ extern "C" {
  * Two stable releases of the same series usually have the same ::HWLOC_API_VERSION
  * even if their HWLOC_VERSION are different.
  */
-#define HWLOC_API_VERSION 0x00020800
+#define HWLOC_API_VERSION 0x00030000
 
 /** \brief Indicate at runtime which hwloc API version was used at build time.
  *
@@ -633,6 +633,7 @@ union hwloc_obj_attr_u {
   struct hwloc_pcidev_attr_s {
     unsigned int domain;
     unsigned char bus, dev, func;
+    unsigned char prog_if; /* the register-level programming interface */
     unsigned short class_id;
     unsigned short vendor_id, device_id, subvendor_id, subdevice_id;
     unsigned char revision;