patch-2.4.20 linux-2.4.20/arch/x86_64/mm/k8topology.c

• Lines: 186
• Date: Thu Nov 28 15:53:12 2002
• Orig file: linux-2.4.19/arch/x86_64/mm/k8topology.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.19/arch/x86_64/mm/k8topology.c linux-2.4.20/arch/x86_64/mm/k8topology.c
@@ -0,0 +1,185 @@
+/* 
+ * AMD K8 NUMA support.
+ * Discover the memory map and associated nodes.
+ * 
+ * Doesn't use the ACPI SRAT table because it has a questionable license.
+ * Instead the northbridge registers are read directly. 
+ * 
+ * Copyright 2002 Andi Kleen, SuSE Labs.
+ * $Id: k8topology.c,v 1.3 2002/09/12 12:51:39 ak Exp $
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/string.h>
+#include <linux/module.h>
+#include <asm/io.h>
+#include <linux/pci_ids.h>
+#include <asm/types.h>
+#include <asm/mmzone.h>
+#include <asm/proto.h>
+#include <asm/e820.h>
+#include <asm/pci-direct.h>
+
+int memnode_shift;
+u8  memnodemap[NODEMAPSIZE];
+
+static int find_northbridge(void)
+{
+	int num; 
+
+	for (num = 0; num < 32; num++) { 
+		u32 header;
+		
+		header = read_pci_config(0, num, 0, 0x00);  
+		if (header != (PCI_VENDOR_ID_AMD | (0x1100<<16)))
+			continue; 	
+
+		header = read_pci_config(0, num, 1, 0x00); 
+		if (header != (PCI_VENDOR_ID_AMD | (0x1101<<16)))
+			continue;	
+		return num; 
+	} 
+
+	return -1; 	
+}
+
+#define MAXNODE 8 
+#define NODEMASK 0xff
+
+struct node { 
+	u64 start,end; 
+};
+
+#define for_all_nodes(n) \
+	for (n=0; n<MAXNODE;n++) if (nodes[n].start!=nodes[n].end)
+
+static int compute_hash_shift(struct node *nodes, int numnodes, u64 maxmem)
+{
+	int i; 
+	int shift = 24;
+	u64 addr;
+	
+	/* When in doubt use brute force. */
+	while (shift < 48) { 
+		memset(memnodemap,0xff,sizeof(*memnodemap) * NODEMAPSIZE); 
+		for_all_nodes (i) { 
+			for (addr = nodes[i].start; 
+			     addr < nodes[i].end; 
+			     addr += (1UL << shift)) {
+				if (memnodemap[addr >> shift] != 0xff) { 
+					printk("node %d shift %d addr %Lx conflict %d\n", 
+					       i, shift, addr, memnodemap[addr>>shift]);
+					goto next; 
+				} 
+				memnodemap[addr >> shift] = i; 
+			} 
+		} 
+		return shift; 
+	next:
+		shift++; 
+	} 
+	memset(memnodemap,0,sizeof(*memnodemap) * NODEMAPSIZE); 
+	return -1; 
+}
+
+extern unsigned long nodes_present;
+extern unsigned long end_pfn;
+
+int __init k8_scan_nodes(unsigned long start, unsigned long end)
+{ 
+	unsigned long prevbase;
+	struct node nodes[MAXNODE];
+	int nodeid, numnodes, maxnode, i, nb; 
+
+	nb = find_northbridge(); 
+	if (nb < 0) 
+		return nb;
+
+	printk(KERN_INFO "Scanning NUMA topology in Northbridge %d\n", nb); 
+
+	numnodes = (read_pci_config(0, nb, 0, 0x60 ) >> 4) & 3; 
+
+	memset(&nodes,0,sizeof(nodes)); 
+	prevbase = 0;
+	maxnode = -1; 
+	for (i = 0; i < MAXNODE; i++) { 
+		unsigned long base,limit; 
+
+		base = read_pci_config(0, nb, 1, 0x40 + i*8);
+		limit = read_pci_config(0, nb, 1, 0x44 + i*8);
+
+		nodeid = limit & 3; 
+		if (!limit) { 
+			printk(KERN_INFO "Skipping node entry %d (base %lx)\n", i,			       base);
+			continue;
+		}
+		if ((base >> 8) & 3 || (limit >> 8) & 3) {
+			printk(KERN_ERR "Node %d using interleaving mode %lx/%lx\n", 
+			       nodeid, (base>>8)&3, (limit>>8) & 3); 
+			return -1; 
+		}	
+		if (nodeid > maxnode) 
+			maxnode = nodeid; 
+		if ((1UL << nodeid) & nodes_present) { 
+			printk("Node %d already present. Skipping\n", nodeid);
+			continue;
+		}
+
+		limit >>= 16; 
+		limit <<= 24; 
+
+		if (limit > end_pfn << PAGE_SHIFT) 
+			limit = end_pfn << PAGE_SHIFT; 
+		if (limit <= base) { 
+			printk(KERN_INFO "Node %d beyond memory map\n", nodeid);
+			continue; 
+		} 
+			
+		base >>= 16;
+		base <<= 24; 
+
+		if (base < start) 
+			base = start; 
+		if (limit > end) 
+			limit = end; 
+		if (limit == base) 
+			continue; 
+		if (limit < base) { 
+			printk(KERN_INFO"Node %d bogus settings %lx-%lx. Ignored.\n",
+			       nodeid, base, limit); 			       
+			continue; 
+		} 
+		
+		/* Could sort here, but pun for now. Should not happen anyroads. */
+		if (prevbase > base) { 
+			printk(KERN_INFO "Node map not sorted %lx,%lx\n",
+			       prevbase,base);
+			return -1;
+		}
+			
+		printk(KERN_INFO "Node %d MemBase %016lx Limit %016lx\n", 
+		       nodeid, base, limit); 
+		
+		nodes[nodeid].start = base; 
+		nodes[nodeid].end = limit;
+
+		prevbase = base;
+	} 
+
+	if (maxnode <= 0)
+		return -1; 
+
+	memnode_shift = compute_hash_shift(nodes,maxnode,end);
+	if (memnode_shift < 0) { 
+		printk(KERN_ERR "No NUMA node hash function found. Contact maintainer\n"); 
+		return -1; 
+	} 
+	printk(KERN_INFO "Using node hash shift of %d\n", memnode_shift); 
+
+	for_all_nodes(i) { 
+		setup_node_bootmem(i, nodes[i].start, nodes[i].end); 
+	} 
+
+	return 0;
+} 
+