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-rw-r--r--arch/x86/mm/amdtopology.c183
1 files changed, 183 insertions, 0 deletions
diff --git a/arch/x86/mm/amdtopology.c b/arch/x86/mm/amdtopology.c
new file mode 100644
index 000000000..058b2f36b
--- /dev/null
+++ b/arch/x86/mm/amdtopology.c
@@ -0,0 +1,183 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AMD NUMA support.
+ * Discover the memory map and associated nodes.
+ *
+ * This version reads it directly from the AMD northbridge.
+ *
+ * Copyright 2002,2003 Andi Kleen, SuSE Labs.
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/string.h>
+#include <linux/nodemask.h>
+#include <linux/memblock.h>
+
+#include <asm/io.h>
+#include <linux/pci_ids.h>
+#include <linux/acpi.h>
+#include <asm/types.h>
+#include <asm/mmzone.h>
+#include <asm/proto.h>
+#include <asm/e820/api.h>
+#include <asm/pci-direct.h>
+#include <asm/numa.h>
+#include <asm/mpspec.h>
+#include <asm/apic.h>
+#include <asm/amd_nb.h>
+
+static unsigned char __initdata nodeids[8];
+
+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)) &&
+ header != (PCI_VENDOR_ID_AMD | (0x1200<<16)) &&
+ header != (PCI_VENDOR_ID_AMD | (0x1300<<16)))
+ continue;
+
+ header = read_pci_config(0, num, 1, 0x00);
+ if (header != (PCI_VENDOR_ID_AMD | (0x1101<<16)) &&
+ header != (PCI_VENDOR_ID_AMD | (0x1201<<16)) &&
+ header != (PCI_VENDOR_ID_AMD | (0x1301<<16)))
+ continue;
+ return num;
+ }
+
+ return -ENOENT;
+}
+
+int __init amd_numa_init(void)
+{
+ u64 start = PFN_PHYS(0);
+ u64 end = PFN_PHYS(max_pfn);
+ unsigned numnodes;
+ u64 prevbase;
+ int i, j, nb;
+ u32 nodeid, reg;
+ unsigned int bits, cores, apicid_base;
+
+ if (!early_pci_allowed())
+ return -EINVAL;
+
+ nb = find_northbridge();
+ if (nb < 0)
+ return nb;
+
+ pr_info("Scanning NUMA topology in Northbridge %d\n", nb);
+
+ reg = read_pci_config(0, nb, 0, 0x60);
+ numnodes = ((reg >> 4) & 0xF) + 1;
+ if (numnodes <= 1)
+ return -ENOENT;
+
+ pr_info("Number of physical nodes %d\n", numnodes);
+
+ prevbase = 0;
+ for (i = 0; i < 8; i++) {
+ u64 base, limit;
+
+ base = read_pci_config(0, nb, 1, 0x40 + i*8);
+ limit = read_pci_config(0, nb, 1, 0x44 + i*8);
+
+ nodeids[i] = nodeid = limit & 7;
+ if ((base & 3) == 0) {
+ if (i < numnodes)
+ pr_info("Skipping disabled node %d\n", i);
+ continue;
+ }
+ if (nodeid >= numnodes) {
+ pr_info("Ignoring excess node %d (%Lx:%Lx)\n", nodeid,
+ base, limit);
+ continue;
+ }
+
+ if (!limit) {
+ pr_info("Skipping node entry %d (base %Lx)\n",
+ i, base);
+ continue;
+ }
+ if ((base >> 8) & 3 || (limit >> 8) & 3) {
+ pr_err("Node %d using interleaving mode %Lx/%Lx\n",
+ nodeid, (base >> 8) & 3, (limit >> 8) & 3);
+ return -EINVAL;
+ }
+ if (node_isset(nodeid, numa_nodes_parsed)) {
+ pr_info("Node %d already present, skipping\n",
+ nodeid);
+ continue;
+ }
+
+ limit >>= 16;
+ limit++;
+ limit <<= 24;
+
+ if (limit > end)
+ limit = end;
+ if (limit <= base)
+ continue;
+
+ base >>= 16;
+ base <<= 24;
+
+ if (base < start)
+ base = start;
+ if (limit > end)
+ limit = end;
+ if (limit == base) {
+ pr_err("Empty node %d\n", nodeid);
+ continue;
+ }
+ if (limit < base) {
+ pr_err("Node %d bogus settings %Lx-%Lx.\n",
+ nodeid, base, limit);
+ continue;
+ }
+
+ /* Could sort here, but pun for now. Should not happen anyroads. */
+ if (prevbase > base) {
+ pr_err("Node map not sorted %Lx,%Lx\n",
+ prevbase, base);
+ return -EINVAL;
+ }
+
+ pr_info("Node %d MemBase %016Lx Limit %016Lx\n",
+ nodeid, base, limit);
+
+ prevbase = base;
+ numa_add_memblk(nodeid, base, limit);
+ node_set(nodeid, numa_nodes_parsed);
+ }
+
+ if (!nodes_weight(numa_nodes_parsed))
+ return -ENOENT;
+
+ /*
+ * We seem to have valid NUMA configuration. Map apicids to nodes
+ * using the coreid bits from early_identify_cpu.
+ */
+ bits = boot_cpu_data.x86_coreid_bits;
+ cores = 1 << bits;
+ apicid_base = 0;
+
+ /*
+ * get boot-time SMP configuration:
+ */
+ early_get_smp_config();
+
+ if (boot_cpu_physical_apicid > 0) {
+ pr_info("BSP APIC ID: %02x\n", boot_cpu_physical_apicid);
+ apicid_base = boot_cpu_physical_apicid;
+ }
+
+ for_each_node_mask(i, numa_nodes_parsed)
+ for (j = apicid_base; j < cores + apicid_base; j++)
+ set_apicid_to_node((i << bits) + j, i);
+
+ return 0;
+}