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-rw-r--r--arch/arm64/kernel/acpi_numa.c120
1 files changed, 120 insertions, 0 deletions
diff --git a/arch/arm64/kernel/acpi_numa.c b/arch/arm64/kernel/acpi_numa.c
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index 0000000000..e51535a5f9
--- /dev/null
+++ b/arch/arm64/kernel/acpi_numa.c
@@ -0,0 +1,120 @@
+// 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/kernel.h>
+#include <linux/mm.h>
+#include <linux/memblock.h>
+#include <linux/mmzone.h>
+#include <linux/module.h>
+#include <linux/topology.h>
+
+#include <asm/numa.h>
+
+static int acpi_early_node_map[NR_CPUS] __initdata = { NUMA_NO_NODE };
+
+int __init acpi_numa_get_nid(unsigned int cpu)
+{
+ return acpi_early_node_map[cpu];
+}
+
+static inline int get_cpu_for_acpi_id(u32 uid)
+{
+ int cpu;
+
+ for (cpu = 0; cpu < nr_cpu_ids; cpu++)
+ if (uid == get_acpi_id_for_cpu(cpu))
+ return cpu;
+
+ return -EINVAL;
+}
+
+static int __init acpi_parse_gicc_pxm(union acpi_subtable_headers *header,
+ const unsigned long end)
+{
+ struct acpi_srat_gicc_affinity *pa;
+ int cpu, pxm, node;
+
+ if (srat_disabled())
+ return -EINVAL;
+
+ pa = (struct acpi_srat_gicc_affinity *)header;
+ if (!pa)
+ return -EINVAL;
+
+ if (!(pa->flags & ACPI_SRAT_GICC_ENABLED))
+ return 0;
+
+ pxm = pa->proximity_domain;
+ node = pxm_to_node(pxm);
+
+ /*
+ * If we can't map the UID to a logical cpu this
+ * means that the UID is not part of possible cpus
+ * so we do not need a NUMA mapping for it, skip
+ * the SRAT entry and keep parsing.
+ */
+ cpu = get_cpu_for_acpi_id(pa->acpi_processor_uid);
+ if (cpu < 0)
+ return 0;
+
+ acpi_early_node_map[cpu] = node;
+ pr_info("SRAT: PXM %d -> MPIDR 0x%llx -> Node %d\n", pxm,
+ cpu_logical_map(cpu), node);
+
+ return 0;
+}
+
+void __init acpi_map_cpus_to_nodes(void)
+{
+ acpi_table_parse_entries(ACPI_SIG_SRAT, sizeof(struct acpi_table_srat),
+ ACPI_SRAT_TYPE_GICC_AFFINITY,
+ acpi_parse_gicc_pxm, 0);
+}
+
+/* Callback for Proximity Domain -> ACPI processor UID mapping */
+void __init acpi_numa_gicc_affinity_init(struct acpi_srat_gicc_affinity *pa)
+{
+ int pxm, node;
+
+ 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;
+
+ pxm = pa->proximity_domain;
+ node = acpi_map_pxm_to_node(pxm);
+
+ if (node == NUMA_NO_NODE) {
+ pr_err("SRAT: Too many proximity domains %d\n", pxm);
+ bad_srat();
+ return;
+ }
+
+ node_set(node, numa_nodes_parsed);
+}
+