text: // SPDX-License-Identifier: GPL-2.0
  /*
   * ACPI 5.1 based NUMA setup for ARM64
   * Lots of code was borrowed from arch/x86/mm/srat.c
   *
   * Copyright 2004 Andi Kleen, SuSE Labs.
   * Copyright (C) 2013-2016, Linaro Ltd.
   *		Author: Hanjun Guo <hanjun.guo@linaro.org>
   *
   * Reads the ACPI SRAT table to figure out what memory belongs to which CPUs.
   *
   * Called from acpi_numa_init while reading the SRAT and SLIT tables.
   * Assumes all memory regions belonging to a single proximity domain
   * are in one chunk. Holes between them will be included in the node.
   */
  
  #define pr_fmt(fmt) "ACPI: NUMA: " fmt
  
  #include <linux/acpi.h>
  #include <linux/bitmap.h>
  #include <linux/bootmem.h>
  #include <linux/kernel.h>
  #include <linux/mm.h>
  #include <linux/memblock.h>
  #include <linux/mmzone.h>
  #include <linux/module.h>
  #include <linux/topology.h>
  
  #include <acpi/processor.h>
  #include <asm/numa.h>
  
  static int cpus_in_srat;
  
  struct __node_cpu_hwid {
  	u32 node_id;    /* logical node containing this CPU */
  	u64 cpu_hwid;   /* MPIDR for this CPU */
  };
  
  static struct __node_cpu_hwid early_node_cpu_hwid[NR_CPUS] = {
  [0 ... NR_CPUS - 1] = {NUMA_NO_NODE, PHYS_CPUID_INVALID} };
  
  int acpi_numa_get_nid(unsigned int cpu, u64 hwid)
  {
  	int i;
  
  	for (i = 0; i < cpus_in_srat; i++) {
  		if (hwid == early_node_cpu_hwid[i].cpu_hwid)
  			return early_node_cpu_hwid[i].node_id;
  	}
  
  	return NUMA_NO_NODE;
  }
  
  /* Callback for Proximity Domain -> ACPI processor UID mapping */
  void __init acpi_numa_gicc_affinity_init(struct acpi_srat_gicc_affinity *pa)
  {
  	int pxm, node;
  	phys_cpuid_t mpidr;
  
  	if (srat_disabled())
  		return;
  
  	if (pa->header.length < sizeof(struct acpi_srat_gicc_affinity)) {
  		pr_err("SRAT: Invalid SRAT header length: %d\n",
  			pa->header.length);
  		bad_srat();
  		return;
  	}
  
  	if (!(pa->flags & ACPI_SRAT_GICC_ENABLED))
  		return;
  
  	if (cpus_in_srat >= NR_CPUS) {
  		pr_warn_once("SRAT: cpu_to_node_map[%d] is too small, may not be able to use all cpus\n",
  			     NR_CPUS);
  		return;
  	}
  
  	pxm = pa->proximity_domain;
  	node = acpi_map_pxm_to_node(pxm);
  
  	if (node == NUMA_NO_NODE || node >= MAX_NUMNODES) {
  		pr_err("SRAT: Too many proximity domains %d\n", pxm);
  		bad_srat();
  		return;
  	}
  
  	mpidr = acpi_map_madt_entry(pa->acpi_processor_uid);
  	if (mpidr == PHYS_CPUID_INVALID) {
  		pr_err("SRAT: PXM %d with ACPI ID %d has no valid MPIDR in MADT\n",
  			pxm, pa->acpi_processor_uid);
  		bad_srat();
  		return;
  	}
  
  	early_node_cpu_hwid[cpus_in_srat].node_id = node;
  	early_node_cpu_hwid[cpus_in_srat].cpu_hwid =  mpidr;
  	node_set(node, numa_nodes_parsed);
  	cpus_in_srat++;
  	pr_info("SRAT: PXM %d -> MPIDR 0x%Lx -> Node %d\n",
  		pxm, mpidr, node);
  }
  
  int __init arm64_acpi_numa_init(void)
  {
  	int ret;
  
  	ret = acpi_numa_init();
  	if (ret) {
  		pr_info("Failed to initialise from firmware\n");
  		return ret;
  	}
  
  	return srat_disabled() ? -EINVAL : 0;
  }
  