perf/x86/intel/uncore: With > 8 nodes, get pci bus die id from NUMA info

The registers used to determine which die a pci bus belongs to don't
contain enough information to uniquely specify more than 8 dies, so
when more than 8 dies are present, use NUMA information instead.

Continue to use the previous method for 8 or fewer because it
works there, and covers cases of NUMA being disabled.
Signed-off-by: Steve Wahl <steve.wahl@hpe.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lkml.kernel.org/r/20210108153549.108989-3-steve.wahl@hpe.com

arch/x86/events/intel/uncore_snbep.c

@@ -1370,6 +1370,14 @@ static int snbep_pci2phy_map_init(int devid, int nodeid_loc, int idmap_loc, bool
 		if (!ubox_dev)
 			break;
 		bus = ubox_dev->bus->number;
+		/*
+		 * The nodeid and idmap registers only contain enough
+		 * information to handle 8 nodes.  On systems with more
+		 * than 8 nodes, we need to rely on NUMA information,
+		 * filled in from BIOS supplied information, to determine
+		 * the topology.
+		 */
+		if (nr_node_ids <= 8) {
 			/* get the Node ID of the local register */
 			err = pci_read_config_dword(ubox_dev, nodeid_loc, &config);
 			if (err)
@@ -1404,6 +1412,35 @@ static int snbep_pci2phy_map_init(int devid, int nodeid_loc, int idmap_loc, bool
 				}
 			}
 			raw_spin_unlock(&pci2phy_map_lock);
+		} else {
+			int node = pcibus_to_node(ubox_dev->bus);
+			int cpu;
+
+			segment = pci_domain_nr(ubox_dev->bus);
+			raw_spin_lock(&pci2phy_map_lock);
+			map = __find_pci2phy_map(segment);
+			if (!map) {
+				raw_spin_unlock(&pci2phy_map_lock);
+				err = -ENOMEM;
+				break;
+			}
+
+			die_id = -1;
+			for_each_cpu(cpu, cpumask_of_pcibus(ubox_dev->bus)) {
+				struct cpuinfo_x86 *c = &cpu_data(cpu);
+
+				if (c->initialized && cpu_to_node(cpu) == node) {
+					map->pbus_to_dieid[bus] = die_id = c->logical_die_id;
+					break;
+				}
+			}
+			raw_spin_unlock(&pci2phy_map_lock);
+
+			if (WARN_ON_ONCE(die_id == -1)) {
+				err = -EINVAL;
+				break;
+			}
+		}
 	}
 
 	if (!err) {