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                         header != (PCI_VENDOR_ID_AMD | (0x1200<<16)) &&
  33                         header != (PCI_VENDOR_ID_AMD | (0x1300<<16)))
  34                         continue;
  35
  36                 header = read_pci_config(0, num, 1, 0x00);
  37                 if (header != (PCI_VENDOR_ID_AMD | (0x1101<<16)) &&
  38                         header != (PCI_VENDOR_ID_AMD | (0x1201<<16)) &&
  39                         header != (PCI_VENDOR_ID_AMD | (0x1301<<16)))
  40                         continue;
  41                 return num;
  42         }
  43
  44         return -1;
  45 }
  46
  47 int __init k8_scan_nodes(unsigned long start, unsigned long end)
  48 {
  49         unsigned long prevbase;
  50         struct bootnode nodes[8];
  51         int nodeid, i, nb;
  52         unsigned char nodeids[8];
  53         int found = 0;
  54         u32 reg;
  55         unsigned numnodes;
  56         unsigned cores;
  57         unsigned bits;
  58         int j;
  59
  60         if (!early_pci_allowed())
  61                 return -1;
  62
  63         nb = find_northbridge();
  64         if (nb < 0)
  65                 return nb;
  66
  67         printk(KERN_INFO "Scanning NUMA topology in Northbridge %d\n", nb);
  68
  69         reg = read_pci_config(0, nb, 0, 0x60);
  70         numnodes = ((reg >> 4) & 0xF) + 1;
  71         if (numnodes <= 1)
  72                 return -1;
  73
  74         printk(KERN_INFO "Number of nodes %d\n", numnodes);
  75
  76         memset(&nodes, 0, sizeof(nodes));
  77         prevbase = 0;
  78         for (i = 0; i < 8; i++) {
  79                 unsigned long base, limit;
  80                 u32 nodeid;
  81
  82                 base = read_pci_config(0, nb, 1, 0x40 + i*8);
  83                 limit = read_pci_config(0, nb, 1, 0x44 + i*8);
  84
  85                 nodeid = limit & 7;
  86                 nodeids[i] = nodeid;
  87                 if ((base & 3) == 0) {
  88                         if (i < numnodes)
  89                                 printk("Skipping disabled node %d\n", i);
  90                         continue;
  91                 }
  92                 if (nodeid >= numnodes) {
  93                         printk("Ignoring excess node %d (%lx:%lx)\n", nodeid,
  94                                base, limit);
  95                         continue;
  96                 }
  97
  98                 if (!limit) {
  99                         printk(KERN_INFO "Skipping node entry %d (base %lx)\n",
 100                                i, base);
 101                         continue;
 102                 }
 103                 if ((base >> 8) & 3 || (limit >> 8) & 3) {
 104                         printk(KERN_ERR "Node %d using interleaving mode %lx/%lx\n",
 105                                nodeid, (base>>8)&3, (limit>>8) & 3);
 106                         return -1;
 107                 }
 108                 if (node_isset(nodeid, node_possible_map)) {
 109                         printk(KERN_INFO "Node %d already present. Skipping\n",
 110                                nodeid);
 111                         continue;
 112                 }
 113
 114                 limit >>= 16;
 115                 limit <<= 24;
 116                 limit |= (1<<24)-1;
 117                 limit++;
 118
 119                 if (limit > end_pfn << PAGE_SHIFT)
 120                         limit = end_pfn << PAGE_SHIFT;
 121                 if (limit <= base)
 122                         continue;
 123
 124                 base >>= 16;
 125                 base <<= 24;
 126
 127                 if (base < start)
 128                         base = start;
 129                 if (limit > end)
 130                         limit = end;
 131                 if (limit == base) {
 132                         printk(KERN_ERR "Empty node %d\n", nodeid);
 133                         continue;
 134                 }
 135                 if (limit < base) {
 136                         printk(KERN_ERR "Node %d bogus settings %lx-%lx.\n",
 137                                nodeid, base, limit);
 138                         continue;
 139                 }
 140
 141                 /* Could sort here, but pun for now. Should not happen anyroads. */
 142                 if (prevbase > base) {
 143                         printk(KERN_ERR "Node map not sorted %lx,%lx\n",
 144                                prevbase, base);
 145                         return -1;
 146                 }
 147
 148                 printk(KERN_INFO "Node %d MemBase %016lx Limit %016lx\n",
 149                        nodeid, base, limit);
 150
 151                 found++;
 152
 153                 nodes[nodeid].start = base;
 154                 nodes[nodeid].end = limit;
 155                 e820_register_active_regions(nodeid,
 156                                 nodes[nodeid].start >> PAGE_SHIFT,
 157                                 nodes[nodeid].end >> PAGE_SHIFT);
 158
 159                 prevbase = base;
 160
 161                 node_set(nodeid, node_possible_map);
 162         }
 163
 164         if (!found)
 165                 return -1;
 166
 167         memnode_shift = compute_hash_shift(nodes, 8, NULL);
 168         if (memnode_shift < 0) {
 169                 printk(KERN_ERR "No NUMA node hash function found. Contact maintainer\n");
 170                 return -1;
 171         }
 172         printk(KERN_INFO "Using node hash shift of %d\n", memnode_shift);
 173
 174         /* use the coreid bits from early_identify_cpu */
 175         bits = boot_cpu_data.x86_coreid_bits;
 176         cores = (1<<bits);
 177
 178         for (i = 0; i < 8; i++) {
 179                 if (nodes[i].start != nodes[i].end) {
 180                         nodeid = nodeids[i];
 181                         for (j = 0; j < cores; j++)
 182                                 apicid_to_node[(nodeid << bits) + j] = i;
 183                         setup_node_bootmem(i, nodes[i].start, nodes[i].end);
 184                 }
 185         }
 186
 187         numa_init_array();
 188         return 0;
 189 }