arch/x86/mm/k8topology_64.c

   1 /*
   2  * AMD K8 NUMA support.
   3  * Discover the memory map and associated nodes.
   4  *
   5  * This version reads it directly from the K8 northbridge.
   6  *
   7  * Copyright 2002,2003 Andi Kleen, SuSE Labs.
   8  */
   9 #include <linux/kernel.h>
  10 #include <linux/init.h>
  11 #include <linux/string.h>
  12 #include <linux/module.h>
  13 #include <linux/nodemask.h>
  14 #include <asm/io.h>
  15 #include <linux/pci_ids.h>
  16 #include <asm/types.h>
  17 #include <asm/mmzone.h>
  18 #include <asm/proto.h>
  19 #include <asm/e820.h>
  20 #include <asm/pci-direct.h>
  21 #include <asm/numa.h>
  22
  23 static __init int find_northbridge(void)
  24 {
  25         int num;
  26
  27         for (num = 0; num < 32; num++) {
  28                 u32 header;
  29
  30                 header = read_pci_config(0, num, 0, 0x00);
  31                 if (header != (PCI_VENDOR_ID_AMD | (0x1100<<16)))
  32                         continue;
  33
  34                 header = read_pci_config(0, num, 1, 0x00);
  35                 if (header != (PCI_VENDOR_ID_AMD | (0x1101<<16)))
  36                         continue;
  37                 return num;
  38         }
  39
  40         return -1;
  41 }
  42
  43 int __init k8_scan_nodes(unsigned long start, unsigned long end)
  44 {
  45         unsigned long prevbase;
  46         struct bootnode nodes[8];
  47         int nodeid, i, nb;
  48         unsigned char nodeids[8];
  49         int found = 0;
  50         u32 reg;
  51         unsigned numnodes;
  52         unsigned cores;
  53         unsigned bits;
  54         int j;
  55
  56         if (!early_pci_allowed())
  57                 return -1;
  58
  59         nb = find_northbridge();
  60         if (nb < 0)
  61                 return nb;
  62
  63         printk(KERN_INFO "Scanning NUMA topology in Northbridge %d\n", nb);
  64
  65         reg = read_pci_config(0, nb, 0, 0x60);
  66         numnodes = ((reg >> 4) & 0xF) + 1;
  67         if (numnodes <= 1)
  68                 return -1;
  69
  70         printk(KERN_INFO "Number of nodes %d\n", numnodes);
  71
  72         memset(&nodes, 0, sizeof(nodes));
  73         prevbase = 0;
  74         for (i = 0; i < 8; i++) {
  75                 unsigned long base, limit;
  76                 u32 nodeid;
  77
  78                 base = read_pci_config(0, nb, 1, 0x40 + i*8);
  79                 limit = read_pci_config(0, nb, 1, 0x44 + i*8);
  80
  81                 nodeid = limit & 7;
  82                 nodeids[i] = nodeid;
  83                 if ((base & 3) == 0) {
  84                         if (i < numnodes)
  85                                 printk("Skipping disabled node %d\n", i);
  86                         continue;
  87                 }
  88                 if (nodeid >= numnodes) {
  89                         printk("Ignoring excess node %d (%lx:%lx)\n", nodeid,
  90                                base, limit);
  91                         continue;
  92                 }
  93
  94                 if (!limit) {
  95                         printk(KERN_INFO "Skipping node entry %d (base %lx)\n",
  96                                i, base);
  97                         continue;
  98                 }
  99                 if ((base >> 8) & 3 || (limit >> 8) & 3) {
 100                         printk(KERN_ERR "Node %d using interleaving mode %lx/%lx\n",
 101                                nodeid, (base>>8)&3, (limit>>8) & 3);
 102                         return -1;
 103                 }
 104                 if (node_isset(nodeid, node_possible_map)) {
 105                         printk(KERN_INFO "Node %d already present. Skipping\n",
 106                                nodeid);
 107                         continue;
 108                 }
 109
 110                 limit >>= 16;
 111                 limit <<= 24;
 112                 limit |= (1<<24)-1;
 113                 limit++;
 114
 115                 if (limit > end_pfn << PAGE_SHIFT)
 116                         limit = end_pfn << PAGE_SHIFT;
 117                 if (limit <= base)
 118                         continue;
 119
 120                 base >>= 16;
 121                 base <<= 24;
 122
 123                 if (base < start)
 124                         base = start;
 125                 if (limit > end)
 126                         limit = end;
 127                 if (limit == base) {
 128                         printk(KERN_ERR "Empty node %d\n", nodeid);
 129                         continue;
 130                 }
 131                 if (limit < base) {
 132                         printk(KERN_ERR "Node %d bogus settings %lx-%lx.\n",
 133                                nodeid, base, limit);
 134                         continue;
 135                 }
 136
 137                 /* Could sort here, but pun for now. Should not happen anyroads. */
 138                 if (prevbase > base) {
 139                         printk(KERN_ERR "Node map not sorted %lx,%lx\n",
 140                                prevbase, base);
 141                         return -1;
 142                 }
 143
 144                 printk(KERN_INFO "Node %d MemBase %016lx Limit %016lx\n",
 145                        nodeid, base, limit);
 146
 147                 found++;
 148
 149                 nodes[nodeid].start = base;
 150                 nodes[nodeid].end = limit;
 151                 e820_register_active_regions(nodeid,
 152                                 nodes[nodeid].start >> PAGE_SHIFT,
 153                                 nodes[nodeid].end >> PAGE_SHIFT);
 154
 155                 prevbase = base;
 156
 157                 node_set(nodeid, node_possible_map);
 158         }
 159
 160         if (!found)
 161                 return -1;
 162
 163         memnode_shift = compute_hash_shift(nodes, 8);
 164         if (memnode_shift < 0) {
 165                 printk(KERN_ERR "No NUMA node hash function found. Contact maintainer\n");
 166                 return -1;
 167         }
 168         printk(KERN_INFO "Using node hash shift of %d\n", memnode_shift);
 169
 170         /* use the coreid bits from early_identify_cpu */
 171         bits = boot_cpu_data.x86_coreid_bits;
 172         cores = (1<<bits);
 173
 174         for (i = 0; i < 8; i++) {
 175                 if (nodes[i].start != nodes[i].end) {
 176                         nodeid = nodeids[i];
 177                         for (j = 0; j < cores; j++)
 178                                 apicid_to_node[(nodeid << bits) + j] = i;
 179                         setup_node_bootmem(i, nodes[i].start, nodes[i].end);
 180                 }
 181         }
 182
 183         numa_init_array();
 184         return 0;
 185 }