xref: /openbmc/linux/arch/arm64/kernel/acpi_numa.c (revision ba61bb17)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * ACPI 5.1 based NUMA setup for ARM64
4  * Lots of code was borrowed from arch/x86/mm/srat.c
5  *
6  * Copyright 2004 Andi Kleen, SuSE Labs.
7  * Copyright (C) 2013-2016, Linaro Ltd.
8  *		Author: Hanjun Guo <hanjun.guo@linaro.org>
9  *
10  * Reads the ACPI SRAT table to figure out what memory belongs to which CPUs.
11  *
12  * Called from acpi_numa_init while reading the SRAT and SLIT tables.
13  * Assumes all memory regions belonging to a single proximity domain
14  * are in one chunk. Holes between them will be included in the node.
15  */
16 
17 #define pr_fmt(fmt) "ACPI: NUMA: " fmt
18 
19 #include <linux/acpi.h>
20 #include <linux/bitmap.h>
21 #include <linux/bootmem.h>
22 #include <linux/kernel.h>
23 #include <linux/mm.h>
24 #include <linux/memblock.h>
25 #include <linux/mmzone.h>
26 #include <linux/module.h>
27 #include <linux/topology.h>
28 
29 #include <acpi/processor.h>
30 #include <asm/numa.h>
31 
32 static int cpus_in_srat;
33 
34 struct __node_cpu_hwid {
35 	u32 node_id;    /* logical node containing this CPU */
36 	u64 cpu_hwid;   /* MPIDR for this CPU */
37 };
38 
39 static struct __node_cpu_hwid early_node_cpu_hwid[NR_CPUS] = {
40 [0 ... NR_CPUS - 1] = {NUMA_NO_NODE, PHYS_CPUID_INVALID} };
41 
42 int acpi_numa_get_nid(unsigned int cpu, u64 hwid)
43 {
44 	int i;
45 
46 	for (i = 0; i < cpus_in_srat; i++) {
47 		if (hwid == early_node_cpu_hwid[i].cpu_hwid)
48 			return early_node_cpu_hwid[i].node_id;
49 	}
50 
51 	return NUMA_NO_NODE;
52 }
53 
54 /* Callback for Proximity Domain -> ACPI processor UID mapping */
55 void __init acpi_numa_gicc_affinity_init(struct acpi_srat_gicc_affinity *pa)
56 {
57 	int pxm, node;
58 	phys_cpuid_t mpidr;
59 
60 	if (srat_disabled())
61 		return;
62 
63 	if (pa->header.length < sizeof(struct acpi_srat_gicc_affinity)) {
64 		pr_err("SRAT: Invalid SRAT header length: %d\n",
65 			pa->header.length);
66 		bad_srat();
67 		return;
68 	}
69 
70 	if (!(pa->flags & ACPI_SRAT_GICC_ENABLED))
71 		return;
72 
73 	if (cpus_in_srat >= NR_CPUS) {
74 		pr_warn_once("SRAT: cpu_to_node_map[%d] is too small, may not be able to use all cpus\n",
75 			     NR_CPUS);
76 		return;
77 	}
78 
79 	pxm = pa->proximity_domain;
80 	node = acpi_map_pxm_to_node(pxm);
81 
82 	if (node == NUMA_NO_NODE || node >= MAX_NUMNODES) {
83 		pr_err("SRAT: Too many proximity domains %d\n", pxm);
84 		bad_srat();
85 		return;
86 	}
87 
88 	mpidr = acpi_map_madt_entry(pa->acpi_processor_uid);
89 	if (mpidr == PHYS_CPUID_INVALID) {
90 		pr_err("SRAT: PXM %d with ACPI ID %d has no valid MPIDR in MADT\n",
91 			pxm, pa->acpi_processor_uid);
92 		bad_srat();
93 		return;
94 	}
95 
96 	early_node_cpu_hwid[cpus_in_srat].node_id = node;
97 	early_node_cpu_hwid[cpus_in_srat].cpu_hwid =  mpidr;
98 	node_set(node, numa_nodes_parsed);
99 	cpus_in_srat++;
100 	pr_info("SRAT: PXM %d -> MPIDR 0x%Lx -> Node %d\n",
101 		pxm, mpidr, node);
102 }
103 
104 int __init arm64_acpi_numa_init(void)
105 {
106 	int ret;
107 
108 	ret = acpi_numa_init();
109 	if (ret) {
110 		pr_info("Failed to initialise from firmware\n");
111 		return ret;
112 	}
113 
114 	return srat_disabled() ? -EINVAL : 0;
115 }
116