arch/riscv/kernel/acpi_numa.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ACPI 6.6 based NUMA setup for RISCV
   4  * Lots of code was borrowed from arch/arm64/kernel/acpi_numa.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  * Copyright (C) 2024 Intel Corporation.
  10  *
  11  * Reads the ACPI SRAT table to figure out what memory belongs to which CPUs.
  12  *
  13  * Called from acpi_numa_init while reading the SRAT and SLIT tables.
  14  * Assumes all memory regions belonging to a single proximity domain
  15  * are in one chunk. Holes between them will be included in the node.
  16  */
  17
  18 #define pr_fmt(fmt) "ACPI: NUMA: " fmt
  19
  20 #include <linux/acpi.h>
  21 #include <linux/bitmap.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 <asm/numa.h>
  30
  31 static int acpi_early_node_map[NR_CPUS] __initdata = { [0 ... NR_CPUS - 1] = NUMA_NO_NODE };
  32
  33 static int __init acpi_numa_get_nid(unsigned int cpu)
  34 {
  35         return acpi_early_node_map[cpu];
  36 }
  37
  38 static inline int get_cpu_for_acpi_id(u32 uid)
  39 {
  40         int cpu;
  41
  42         for (cpu = 0; cpu < nr_cpu_ids; cpu++)
  43                 if (uid == get_acpi_id_for_cpu(cpu))
  44                         return cpu;
  45
  46         return -EINVAL;
  47 }
  48
  49 static int __init acpi_parse_rintc_pxm(union acpi_subtable_headers *header,
  50                                        const unsigned long end)
  51 {
  52         struct acpi_srat_rintc_affinity *pa;
  53         int cpu, pxm, node;
  54
  55         if (srat_disabled())
  56                 return -EINVAL;
  57
  58         pa = (struct acpi_srat_rintc_affinity *)header;
  59         if (!pa)
  60                 return -EINVAL;
  61
  62         if (!(pa->flags & ACPI_SRAT_RINTC_ENABLED))
  63                 return 0;
  64
  65         pxm = pa->proximity_domain;
  66         node = pxm_to_node(pxm);
  67
  68         /*
  69          * If we can't map the UID to a logical cpu this
  70          * means that the UID is not part of possible cpus
  71          * so we do not need a NUMA mapping for it, skip
  72          * the SRAT entry and keep parsing.
  73          */
  74         cpu = get_cpu_for_acpi_id(pa->acpi_processor_uid);
  75         if (cpu < 0)
  76                 return 0;
  77
  78         acpi_early_node_map[cpu] = node;
  79         pr_info("SRAT: PXM %d -> HARTID 0x%lx -> Node %d\n", pxm,
  80                 cpuid_to_hartid_map(cpu), node);
  81
  82         return 0;
  83 }
  84
  85 void __init acpi_map_cpus_to_nodes(void)
  86 {
  87         int i;
  88
  89         /*
  90          * In ACPI, SMP and CPU NUMA information is provided in separate
  91          * static tables, namely the MADT and the SRAT.
  92          *
  93          * Thus, it is simpler to first create the cpu logical map through
  94          * an MADT walk and then map the logical cpus to their node ids
  95          * as separate steps.
  96          */
  97         acpi_table_parse_entries(ACPI_SIG_SRAT, sizeof(struct acpi_table_srat),
  98                                  ACPI_SRAT_TYPE_RINTC_AFFINITY, acpi_parse_rintc_pxm, 0);
  99
 100         for (i = 0; i < nr_cpu_ids; i++)
 101                 early_map_cpu_to_node(i, acpi_numa_get_nid(i));
 102 }
 103
 104 /* Callback for Proximity Domain -> logical node ID mapping */
 105 void __init acpi_numa_rintc_affinity_init(struct acpi_srat_rintc_affinity *pa)
 106 {
 107         int pxm, node;
 108
 109         if (srat_disabled())
 110                 return;
 111
 112         if (pa->header.length < sizeof(struct acpi_srat_rintc_affinity)) {
 113                 pr_err("SRAT: Invalid SRAT header length: %d\n", pa->header.length);
 114                 bad_srat();
 115                 return;
 116         }
 117
 118         if (!(pa->flags & ACPI_SRAT_RINTC_ENABLED))
 119                 return;
 120
 121         pxm = pa->proximity_domain;
 122         node = acpi_map_pxm_to_node(pxm);
 123
 124         if (node == NUMA_NO_NODE) {
 125                 pr_err("SRAT: Too many proximity domains %d\n", pxm);
 126                 bad_srat();
 127                 return;
 128         }
 129
 130         node_set(node, numa_nodes_parsed);
 131 }