diff --git a/src/device/hypertransport.c b/src/device/hypertransport.c
index 1a2e7ff..84b1aa7 100644
--- a/src/device/hypertransport.c
+++ b/src/device/hypertransport.c
@@ -501,8 +501,8 @@
 					 ht_unitid_base, offset_unitid);
 
 	/* Now that nothing is overlapping it is safe to scan the children. */
-	max = pci_scan_bus(bus, 0x00, ((next_unitid - 1) << 3) | 7, max);
-	return max;
+	bus->subordinate = pci_scan_bus(bus, 0x00, ((next_unitid - 1) << 3) | 7, bus->secondary);
+	return bus->subordinate;
 }
 
 unsigned int ht_scan_bridge(struct device *dev, unsigned int max)
diff --git a/src/northbridge/amd/agesa/family10/northbridge.c b/src/northbridge/amd/agesa/family10/northbridge.c
index 6d0b1b7..9f2555f 100644
--- a/src/northbridge/amd/agesa/family10/northbridge.c
+++ b/src/northbridge/amd/agesa/family10/northbridge.c
@@ -554,13 +554,14 @@
 {
 }
 
-static unsigned amdfam10_scan_chains(device_t dev, unsigned max)
+static unsigned amdfam10_scan_chains(device_t dev, unsigned unused)
 {
 	unsigned nodeid;
 	struct bus *link;
 	unsigned sblink = sysconf.sblk;
 	device_t io_hub = NULL;
 	u32 next_unitid = 0xff;
+	unsigned int max = dev->bus->subordinate;
 
 	nodeid = amdfam10_nodeid(dev);
 	if (nodeid == 0) {
@@ -576,7 +577,9 @@
 		}
 	}
 
-	return max;
+	dev->bus->subordinate = max;
+
+	return unused;
 }
 
 static struct device_operations northbridge_operations = {
@@ -913,7 +916,9 @@
 	}
 
 	for (link = dev->link_list; link; link = link->next) {
-		max = pci_scan_bus(link, PCI_DEVFN(CONFIG_CDB, 0), 0xff, max);
+		link->secondary = dev->bus->subordinate;
+		link->subordinate = pci_scan_bus(link, PCI_DEVFN(CONFIG_CDB, 0), 0xff, link->secondary);
+		dev->bus->subordinate = link->subordinate;
 	}
 
 	/* Tune the hypertransport transaction for best performance.
diff --git a/src/northbridge/amd/agesa/family15/northbridge.c b/src/northbridge/amd/agesa/family15/northbridge.c
index b2d8abd..a4f78f1 100644
--- a/src/northbridge/amd/agesa/family15/northbridge.c
+++ b/src/northbridge/amd/agesa/family15/northbridge.c
@@ -459,12 +459,14 @@
 	}
 }
 
-static unsigned scan_chains(device_t dev, unsigned max)
+static unsigned scan_chains(device_t dev, unsigned unused)
 {
 	unsigned nodeid;
 	struct bus *link;
 	device_t io_hub = NULL;
 	u32 next_unitid = 0x18;
+	unsigned int max = dev->bus->subordinate;
+
 	nodeid = amdfam15_nodeid(dev);
 	if (nodeid == 0) {
 		for (link = dev->link_list; link; link = link->next) {
@@ -479,7 +481,10 @@
 			}
 		}
 	}
-	return max;
+
+	dev->bus->subordinate = max;
+
+	return unused;
 }
 
 
@@ -948,8 +953,9 @@
 /* all family15's pci devices are under 0x18.0, so we search from dev 0x18 fun 0 */
 static unsigned int f15_pci_domain_scan_bus(device_t dev, unsigned int max)
 {
-	max = pci_scan_bus(dev->link_list, PCI_DEVFN(0x18, 0), 0xff, max);
-	return max;
+	struct bus *link = dev->link_list;
+	link->subordinate = pci_scan_bus(link, PCI_DEVFN(0x18, 0), 0xff, link->secondary);
+	return link->subordinate;
 }
 
 static struct device_operations pci_domain_ops = {
diff --git a/src/northbridge/amd/amdfam10/northbridge.c b/src/northbridge/amd/amdfam10/northbridge.c
index a2124f0..121cdf2 100644
--- a/src/northbridge/amd/amdfam10/northbridge.c
+++ b/src/northbridge/amd/amdfam10/northbridge.c
@@ -227,7 +227,7 @@
 		max_bus = 0xfc;
 
 		link->secondary = min_bus;
-		link->subordinate = max_bus;
+		link->subordinate = link->secondary;
 
 		/* Read the existing primary/secondary/subordinate bus
 		 * number configuration.
@@ -245,7 +245,7 @@
 
 		/* set the config map space */
 
-		set_config_map_reg(nodeid, link->link_num, ht_c_index, link->secondary, link->subordinate, sysconf.segbit, sysconf.nodes);
+		set_config_map_reg(nodeid, link->link_num, ht_c_index, link->secondary, max_bus, sysconf.segbit, sysconf.nodes);
 
 		/* Now we can scan all of the subordinate busses i.e. the
 		 * chain on the hypertranport link
@@ -263,16 +263,11 @@
 		next_unitid = hypertransport_scan_chain(link, 0, max_devfn, ht_unitid_base, offset_unit_id(is_sblink));
 
 		/* Now that nothing is overlapping it is safe to scan the children. */
-		max = pci_scan_bus(link, 0x00, ((next_unitid - 1) << 3) | 7, max);
+		link->subordinate = pci_scan_bus(link, 0x00, ((next_unitid - 1) << 3) | 7, link->secondary);
 
 		/* We know the number of busses behind this bridge.  Set the
 		 * subordinate bus number to it's real value
 		 */
-		if(ht_c_index>3) { // clear the extend reg
-			clear_config_map_reg(nodeid, link->link_num, ht_c_index, (max+1)>>sysconf.segbit, (link->subordinate)>>sysconf.segbit, sysconf.nodes);
-		}
-
-		link->subordinate = max;
 		set_config_map_reg(nodeid, link->link_num, ht_c_index, link->secondary, link->subordinate, sysconf.segbit, sysconf.nodes);
 		sysconf.ht_c_num++;
 
@@ -286,15 +281,16 @@
 			sysconf.hcdn_reg[ht_c_index] = temp;
 
 		}
-	store_ht_c_conf_bus(nodeid, link->link_num, ht_c_index, link->secondary, link->subordinate, &sysconf);
-	return max;
+		store_ht_c_conf_bus(nodeid, link->link_num, ht_c_index, link->secondary, link->subordinate, &sysconf);
+		return link->subordinate;
 }
 
-static unsigned amdfam10_scan_chains(device_t dev, unsigned max)
+static unsigned amdfam10_scan_chains(device_t dev, unsigned unused)
 {
 	unsigned nodeid;
 	struct bus *link;
 	unsigned sblink = sysconf.sblk;
+	unsigned int max = dev->bus->subordinate;
 
 	nodeid = amdfam10_nodeid(dev);
 
@@ -312,7 +308,10 @@
 
 		max = amdfam10_scan_chain(dev, nodeid, link, is_sblink, max);
 	}
-	return max;
+
+	dev->bus->subordinate = max;
+
+	return unused;
 }
 
 
@@ -913,7 +912,7 @@
 	}
 }
 
-static u32 amdfam10_domain_scan_bus(device_t dev, u32 max)
+static u32 amdfam10_domain_scan_bus(device_t dev, u32 unused)
 {
 	u32 reg;
 	int i;
@@ -924,7 +923,9 @@
 	}
 
 	for(link = dev->link_list; link; link = link->next) {
-		max = pci_scan_bus(link, PCI_DEVFN(CONFIG_CDB, 0), 0xff, max);
+		link->secondary = dev->bus->subordinate;
+		link->subordinate = pci_scan_bus(link, PCI_DEVFN(CONFIG_CDB, 0), 0xff, link->secondary);
+		dev->bus->subordinate = link->subordinate;
 	}
 
 	/* Tune the hypertransport transaction for best performance.
@@ -948,7 +949,7 @@
 			pci_write_config32(f0_dev, HT_TRANSACTION_CONTROL, httc);
 		}
 	}
-	return max;
+	return unused;
 }
 
 #if IS_ENABLED(CONFIG_GENERATE_SMBIOS_TABLES)
@@ -1213,7 +1214,7 @@
 	last->next = NULL;
 }
 
-static u32 cpu_bus_scan(device_t dev, u32 max)
+static u32 cpu_bus_scan(device_t dev, u32 passthru)
 {
 	struct bus *cpu_bus;
 	device_t dev_mc;
@@ -1382,7 +1383,7 @@
 				amd_cpu_topology(cpu, i, j);
 		} //j
 	}
-	return max;
+	return passthru;
 }
 
 static void cpu_bus_init(device_t dev)
diff --git a/src/northbridge/amd/amdk8/northbridge.c b/src/northbridge/amd/amdk8/northbridge.c
index 29cc5ed..51e1e2d 100644
--- a/src/northbridge/amd/amdk8/northbridge.c
+++ b/src/northbridge/amd/amdk8/northbridge.c
@@ -171,7 +171,7 @@
 		max_bus = 0xff;
 
 		link->secondary = min_bus;
-		link->subordinate = max_bus;
+		link->subordinate = link->secondary;
 
 		/* Read the existing primary/secondary/subordinate bus
 		 * number configuration.
@@ -186,7 +186,7 @@
 		busses &= 0xff000000;
 		busses |= (((unsigned int)(dev->bus->secondary) << 0) |
 			((unsigned int)(link->secondary) << 8) |
-			((unsigned int)(link->subordinate) << 16));
+			(max_bus << 16));
 		pci_write_config32(dev, link->cap + 0x14, busses);
 
 		config_busses &= 0x000fc88;
@@ -195,7 +195,7 @@
 			(( nodeid & 7) << 4) |
 			((link->link_num & 3) << 8) |
 			((link->secondary) << 16) |
-			((link->subordinate) << 24);
+			(max_bus << 24);
 		f1_write_config32(config_reg, config_busses);
 
 		/* Now we can scan all of the subordinate busses i.e. the
@@ -213,12 +213,11 @@
 		next_unitid = hypertransport_scan_chain(link, 0, max_devfn, ht_unitid_base, offset_unit_id(is_sblink));
 
 		/* Now that nothing is overlapping it is safe to scan the children. */
-		max = pci_scan_bus(link, 0x00, ((next_unitid - 1) << 3) | 7, max);
+		link->subordinate = pci_scan_bus(link, 0x00, ((next_unitid - 1) << 3) | 7, link->secondary);
 
 		/* We know the number of busses behind this bridge.  Set the
 		 * subordinate bus number to it's real value
 		 */
-		link->subordinate = max;
 		busses = (busses & 0xff00ffff) |
 			((unsigned int) (link->subordinate) << 16);
 		pci_write_config32(dev, link->cap + 0x14, busses);
@@ -239,14 +238,15 @@
 			sysconf.hcdn_reg[index] = temp;
 
 		}
-	return max;
+		return link->subordinate;
 }
 
-static unsigned amdk8_scan_chains(device_t dev, unsigned max)
+static unsigned amdk8_scan_chains(device_t dev, unsigned unused)
 {
 	unsigned nodeid;
 	struct bus *link;
 	unsigned sblink = 0;
+	unsigned int max = dev->bus->subordinate;
 
 	nodeid = amdk8_nodeid(dev);
 	if (nodeid == 0)
@@ -266,7 +266,10 @@
 
 		max = amdk8_scan_chain(dev, nodeid, link, is_sblink, max);
 	}
-	return max;
+
+	dev->bus->subordinate = max;
+
+	return unused;
 }
 
 
@@ -1096,11 +1099,16 @@
 {
 	u32 reg;
 	int i;
+	struct bus *link = dev->link_list;
+
 	/* Unmap all of the HT chains */
 	for(reg = 0xe0; reg <= 0xec; reg += 4) {
 		f1_write_config32(reg, 0);
 	}
-	max = pci_scan_bus(dev->link_list, PCI_DEVFN(0x18, 0), 0xff, max);
+
+	link->secondary = dev->bus->subordinate;
+	link->subordinate = pci_scan_bus(link, PCI_DEVFN(0x18, 0), 0xff, link->secondary);
+	dev->bus->subordinate = link->subordinate;
 
 	/* Tune the hypertransport transaction for best performance.
 	 * Including enabling relaxed ordering if it is safe.