/* * 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. * XXX in 2.5 we could use the generic SRAT code * * Copyright 2002,2003 Andi Kleen, SuSE Labs. */ #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> #include <asm/numa.h> static __init 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; } int __init k8_scan_nodes(unsigned long start, unsigned long end) { unsigned long prevbase; struct node nodes[MAXNODE]; int nodeid, i, nb; int found = 0; nb = find_northbridge(); if (nb < 0) return nb; printk(KERN_INFO "Scanning NUMA topology in Northbridge %d\n", nb); numnodes = (1 << ((read_pci_config(0, nb, 0, 0x60 ) >> 4) & 3)); printk(KERN_INFO "Assuming %d nodes\n", numnodes - 1); memset(&nodes,0,sizeof(nodes)); prevbase = 0; for (i = 0; i < numnodes; 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_ERR "Skipping node entry %d (base %lx)\n", i, base); return -1; } 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 ((1UL << nodeid) & nodes_present) { printk(KERN_INFO "Node %d already present. Skipping\n", nodeid); continue; } limit >>= 16; limit <<= 24; limit |= (1<<24)-1; if (limit > end_pfn_map << PAGE_SHIFT) limit = end_pfn_map << 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) { printk(KERN_ERR "Empty node %d\n", nodeid); continue; } if (limit < base) { printk(KERN_ERR "Node %d bogus settings %lx-%lx.\n", nodeid, base, limit); return -1; } /* Could sort here, but pun for now. Should not happen anyroads. */ if (prevbase > base) { printk(KERN_ERR "Node map not sorted %lx,%lx\n", prevbase,base); return -1; } printk(KERN_INFO "Node %d MemBase %016lx Limit %016lx\n", nodeid, base, limit); found++; nodes[nodeid].start = base; nodes[nodeid].end = limit; prevbase = base; } if (!found) return -1; memnode_shift = compute_hash_shift(nodes); 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 (i = 0; i < numnodes; i++) { if (nodes[i].start != nodes[i].end) setup_node_bootmem(i, nodes[i].start, nodes[i].end); } return 0; }