1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * AMD NUMA support. 4 * Discover the memory map and associated nodes. 5 * 6 * This version reads it directly from the AMD northbridge. 7 * 8 * Copyright 2002,2003 Andi Kleen, SuSE Labs. 9 */ 10 #include <linux/kernel.h> 11 #include <linux/init.h> 12 #include <linux/string.h> 13 #include <linux/nodemask.h> 14 #include <linux/memblock.h> 15 #include <linux/numa_memblks.h> 16 17 #include <asm/io.h> 18 #include <linux/pci_ids.h> 19 #include <linux/acpi.h> 20 #include <asm/types.h> 21 #include <asm/mmzone.h> 22 #include <asm/proto.h> 23 #include <asm/e820/api.h> 24 #include <asm/pci-direct.h> 25 #include <asm/numa.h> 26 #include <asm/mpspec.h> 27 #include <asm/apic.h> 28 #include <asm/amd_nb.h> 29 30 static unsigned char __initdata nodeids[8]; 31 32 static __init int find_northbridge(void) 33 { 34 int num; 35 36 for (num = 0; num < 32; num++) { 37 u32 header; 38 39 header = read_pci_config(0, num, 0, 0x00); 40 if (header != (PCI_VENDOR_ID_AMD | (0x1100<<16)) && 41 header != (PCI_VENDOR_ID_AMD | (0x1200<<16)) && 42 header != (PCI_VENDOR_ID_AMD | (0x1300<<16))) 43 continue; 44 45 header = read_pci_config(0, num, 1, 0x00); 46 if (header != (PCI_VENDOR_ID_AMD | (0x1101<<16)) && 47 header != (PCI_VENDOR_ID_AMD | (0x1201<<16)) && 48 header != (PCI_VENDOR_ID_AMD | (0x1301<<16))) 49 continue; 50 return num; 51 } 52 53 return -ENOENT; 54 } 55 56 int __init amd_numa_init(void) 57 { 58 unsigned int numnodes, cores, apicid; 59 u64 prevbase, start = PFN_PHYS(0); 60 u64 end = PFN_PHYS(max_pfn); 61 u32 nodeid, reg; 62 int i, j, nb; 63 64 if (!early_pci_allowed()) 65 return -EINVAL; 66 67 nb = find_northbridge(); 68 if (nb < 0) 69 return nb; 70 71 pr_info("Scanning NUMA topology in Northbridge %d\n", nb); 72 73 reg = read_pci_config(0, nb, 0, 0x60); 74 numnodes = ((reg >> 4) & 0xF) + 1; 75 if (numnodes <= 1) 76 return -ENOENT; 77 78 pr_info("Number of physical nodes %d\n", numnodes); 79 80 prevbase = 0; 81 for (i = 0; i < 8; i++) { 82 u64 base, limit; 83 84 base = read_pci_config(0, nb, 1, 0x40 + i*8); 85 limit = read_pci_config(0, nb, 1, 0x44 + i*8); 86 87 nodeids[i] = nodeid = limit & 7; 88 if ((base & 3) == 0) { 89 if (i < numnodes) 90 pr_info("Skipping disabled node %d\n", i); 91 continue; 92 } 93 if (nodeid >= numnodes) { 94 pr_info("Ignoring excess node %d (%Lx:%Lx)\n", nodeid, 95 base, limit); 96 continue; 97 } 98 99 if (!limit) { 100 pr_info("Skipping node entry %d (base %Lx)\n", 101 i, base); 102 continue; 103 } 104 if ((base >> 8) & 3 || (limit >> 8) & 3) { 105 pr_err("Node %d using interleaving mode %Lx/%Lx\n", 106 nodeid, (base >> 8) & 3, (limit >> 8) & 3); 107 return -EINVAL; 108 } 109 if (node_isset(nodeid, numa_nodes_parsed)) { 110 pr_info("Node %d already present, skipping\n", 111 nodeid); 112 continue; 113 } 114 115 limit >>= 16; 116 limit++; 117 limit <<= 24; 118 119 if (limit > end) 120 limit = end; 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 pr_err("Empty node %d\n", nodeid); 133 continue; 134 } 135 if (limit < base) { 136 pr_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 pr_err("Node map not sorted %Lx,%Lx\n", 144 prevbase, base); 145 return -EINVAL; 146 } 147 148 pr_info("Node %d MemBase %016Lx Limit %016Lx\n", 149 nodeid, base, limit); 150 151 prevbase = base; 152 numa_add_memblk(nodeid, base, limit); 153 node_set(nodeid, numa_nodes_parsed); 154 } 155 156 if (nodes_empty(numa_nodes_parsed)) 157 return -ENOENT; 158 159 /* 160 * We seem to have valid NUMA configuration. Map apicids to nodes 161 * using the size of the core domain in the APIC space. 162 */ 163 cores = topology_get_domain_size(TOPO_CORE_DOMAIN); 164 165 apicid = boot_cpu_physical_apicid; 166 if (apicid > 0) 167 pr_info("BSP APIC ID: %02x\n", apicid); 168 169 for_each_node_mask(i, numa_nodes_parsed) { 170 for (j = 0; j < cores; j++, apicid++) 171 set_apicid_to_node(apicid, i); 172 } 173 return 0; 174 } 175