x86_64: make k8topology multi-core aware

This makes k8topology multicore aware instead of limited to signle- and
dual-core CPUs.  It uses the CPUID to be more future proof.
Signed-off-by: Joachim Deguara <joachim.deguara@amd.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/x86_64/mm/k8topology.c

@@ -44,12 +44,12 @@ int __init k8_scan_nodes(unsigned long start, unsigned long end)
 { 
 	unsigned long prevbase;
 	struct bootnode nodes[8];
-	int nodeid, i, nb; 
+	int nodeid, i, j, nb;
 	unsigned char nodeids[8];
 	int found = 0;
 	u32 reg;
 	unsigned numnodes;
-	unsigned dualcore = 0;
+	unsigned num_cores;
 
 	if (!early_pci_allowed())
 		return -1;
@@ -60,6 +60,9 @@ int __init k8_scan_nodes(unsigned long start, unsigned long end)
 
 	printk(KERN_INFO "Scanning NUMA topology in Northbridge %d\n", nb); 
 
+	num_cores = (cpuid_ecx(0x80000008) & 0xff) + 1;
+	printk(KERN_INFO "CPU has %d num_cores\n", num_cores);
+
 	reg = read_pci_config(0, nb, 0, 0x60); 
 	numnodes = ((reg >> 4) & 0xF) + 1;
 	if (numnodes <= 1)
@@ -73,8 +76,6 @@ int __init k8_scan_nodes(unsigned long start, unsigned long end)
 		unsigned long base,limit; 
 		u32 nodeid;
 		
-		/* Undefined before E stepping, but hopefully 0 */
-		dualcore |= ((read_pci_config(0, nb, 3, 0xe8) >> 12) & 3) == 1;
 		base = read_pci_config(0, nb, 1, 0x40 + i*8);
 		limit = read_pci_config(0, nb, 1, 0x44 + i*8);
 
@@ -170,8 +171,8 @@ int __init k8_scan_nodes(unsigned long start, unsigned long end)
 	for (i = 0; i < 8; i++) {
 		if (nodes[i].start != nodes[i].end) { 
 			nodeid = nodeids[i];
-			apicid_to_node[nodeid << dualcore] = i;
-			apicid_to_node[(nodeid << dualcore) + dualcore] = i;
+			for (j = 0; j < num_cores; j++)
+				apicid_to_node[(nodeid * num_cores) + j] = i;
 			setup_node_bootmem(i, nodes[i].start, nodes[i].end); 
 		} 
 	}