arch/arm64/kernel/acpi_numa.c

   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/kernel.h>
  22 #include <linux/mm.h>
  23 #include <linux/memblock.h>
  24 #include <linux/mmzone.h>
  25 #include <linux/module.h>
  26 #include <linux/topology.h>
  27
  28 #include <asm/numa.h>
  29
  30 static int acpi_early_node_map[NR_CPUS] __initdata = { [0 ... NR_CPUS - 1] = NUMA_NO_NODE };
  31
  32 int __init acpi_numa_get_nid(unsigned int cpu)
  33 {
  34         return acpi_early_node_map[cpu];
  35 }
  36
  37 static int __init acpi_parse_gicc_pxm(union acpi_subtable_headers *header,
  38                                       const unsigned long end)
  39 {
  40         struct acpi_srat_gicc_affinity *pa;
  41         int cpu, pxm, node;
  42
  43         if (srat_disabled())
  44                 return -EINVAL;
  45
  46         pa = (struct acpi_srat_gicc_affinity *)header;
  47         if (!pa)
  48                 return -EINVAL;
  49
  50         if (!(pa->flags & ACPI_SRAT_GICC_ENABLED))
  51                 return 0;
  52
  53         pxm = pa->proximity_domain;
  54         node = pxm_to_node(pxm);
  55
  56         /*
  57          * If we can't map the UID to a logical cpu this
  58          * means that the UID is not part of possible cpus
  59          * so we do not need a NUMA mapping for it, skip
  60          * the SRAT entry and keep parsing.
  61          */
  62         cpu = get_cpu_for_acpi_id(pa->acpi_processor_uid);
  63         if (cpu < 0)
  64                 return 0;
  65
  66         acpi_early_node_map[cpu] = node;
  67         pr_info("SRAT: PXM %d -> MPIDR 0x%llx -> Node %d\n", pxm,
  68                 cpu_logical_map(cpu), node);
  69
  70         return 0;
  71 }
  72
  73 void __init acpi_map_cpus_to_nodes(void)
  74 {
  75         acpi_table_parse_entries(ACPI_SIG_SRAT, sizeof(struct acpi_table_srat),
  76                                             ACPI_SRAT_TYPE_GICC_AFFINITY,
  77                                             acpi_parse_gicc_pxm, 0);
  78 }
  79
  80 /* Callback for Proximity Domain -> ACPI processor UID mapping */
  81 void __init acpi_numa_gicc_affinity_init(struct acpi_srat_gicc_affinity *pa)
  82 {
  83         int pxm, node;
  84
  85         if (srat_disabled())
  86                 return;
  87
  88         if (pa->header.length < sizeof(struct acpi_srat_gicc_affinity)) {
  89                 pr_err("SRAT: Invalid SRAT header length: %d\n",
  90                         pa->header.length);
  91                 bad_srat();
  92                 return;
  93         }
  94
  95         if (!(pa->flags & ACPI_SRAT_GICC_ENABLED))
  96                 return;
  97
  98         pxm = pa->proximity_domain;
  99         node = acpi_map_pxm_to_node(pxm);
 100
 101         if (node == NUMA_NO_NODE) {
 102                 pr_err("SRAT: Too many proximity domains %d\n", pxm);
 103                 bad_srat();
 104                 return;
 105         }
 106
 107         node_set(node, numa_nodes_parsed);
 108 }
 109