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-rw-r--r--arch/powerpc/mm/numa.c1479
1 files changed, 1479 insertions, 0 deletions
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
new file mode 100644
index 000000000..16cfe56be
--- /dev/null
+++ b/arch/powerpc/mm/numa.c
@@ -0,0 +1,1479 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * pSeries NUMA support
+ *
+ * Copyright (C) 2002 Anton Blanchard <anton@au.ibm.com>, IBM
+ */
+#define pr_fmt(fmt) "numa: " fmt
+
+#include <linux/threads.h>
+#include <linux/memblock.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/mmzone.h>
+#include <linux/export.h>
+#include <linux/nodemask.h>
+#include <linux/cpu.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+#include <linux/pfn.h>
+#include <linux/cpuset.h>
+#include <linux/node.h>
+#include <linux/stop_machine.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include <asm/cputhreads.h>
+#include <asm/sparsemem.h>
+#include <asm/smp.h>
+#include <asm/topology.h>
+#include <asm/firmware.h>
+#include <asm/paca.h>
+#include <asm/hvcall.h>
+#include <asm/setup.h>
+#include <asm/vdso.h>
+#include <asm/drmem.h>
+
+static int numa_enabled = 1;
+
+static char *cmdline __initdata;
+
+int numa_cpu_lookup_table[NR_CPUS];
+cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
+struct pglist_data *node_data[MAX_NUMNODES];
+
+EXPORT_SYMBOL(numa_cpu_lookup_table);
+EXPORT_SYMBOL(node_to_cpumask_map);
+EXPORT_SYMBOL(node_data);
+
+static int primary_domain_index;
+static int n_mem_addr_cells, n_mem_size_cells;
+
+#define FORM0_AFFINITY 0
+#define FORM1_AFFINITY 1
+#define FORM2_AFFINITY 2
+static int affinity_form;
+
+#define MAX_DISTANCE_REF_POINTS 4
+static int distance_ref_points_depth;
+static const __be32 *distance_ref_points;
+static int distance_lookup_table[MAX_NUMNODES][MAX_DISTANCE_REF_POINTS];
+static int numa_distance_table[MAX_NUMNODES][MAX_NUMNODES] = {
+ [0 ... MAX_NUMNODES - 1] = { [0 ... MAX_NUMNODES - 1] = -1 }
+};
+static int numa_id_index_table[MAX_NUMNODES] = { [0 ... MAX_NUMNODES - 1] = NUMA_NO_NODE };
+
+/*
+ * Allocate node_to_cpumask_map based on number of available nodes
+ * Requires node_possible_map to be valid.
+ *
+ * Note: cpumask_of_node() is not valid until after this is done.
+ */
+static void __init setup_node_to_cpumask_map(void)
+{
+ unsigned int node;
+
+ /* setup nr_node_ids if not done yet */
+ if (nr_node_ids == MAX_NUMNODES)
+ setup_nr_node_ids();
+
+ /* allocate the map */
+ for_each_node(node)
+ alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
+
+ /* cpumask_of_node() will now work */
+ pr_debug("Node to cpumask map for %u nodes\n", nr_node_ids);
+}
+
+static int __init fake_numa_create_new_node(unsigned long end_pfn,
+ unsigned int *nid)
+{
+ unsigned long long mem;
+ char *p = cmdline;
+ static unsigned int fake_nid;
+ static unsigned long long curr_boundary;
+
+ /*
+ * Modify node id, iff we started creating NUMA nodes
+ * We want to continue from where we left of the last time
+ */
+ if (fake_nid)
+ *nid = fake_nid;
+ /*
+ * In case there are no more arguments to parse, the
+ * node_id should be the same as the last fake node id
+ * (we've handled this above).
+ */
+ if (!p)
+ return 0;
+
+ mem = memparse(p, &p);
+ if (!mem)
+ return 0;
+
+ if (mem < curr_boundary)
+ return 0;
+
+ curr_boundary = mem;
+
+ if ((end_pfn << PAGE_SHIFT) > mem) {
+ /*
+ * Skip commas and spaces
+ */
+ while (*p == ',' || *p == ' ' || *p == '\t')
+ p++;
+
+ cmdline = p;
+ fake_nid++;
+ *nid = fake_nid;
+ pr_debug("created new fake_node with id %d\n", fake_nid);
+ return 1;
+ }
+ return 0;
+}
+
+static void __init reset_numa_cpu_lookup_table(void)
+{
+ unsigned int cpu;
+
+ for_each_possible_cpu(cpu)
+ numa_cpu_lookup_table[cpu] = -1;
+}
+
+void map_cpu_to_node(int cpu, int node)
+{
+ update_numa_cpu_lookup_table(cpu, node);
+
+ if (!(cpumask_test_cpu(cpu, node_to_cpumask_map[node]))) {
+ pr_debug("adding cpu %d to node %d\n", cpu, node);
+ cpumask_set_cpu(cpu, node_to_cpumask_map[node]);
+ }
+}
+
+#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PPC_SPLPAR)
+void unmap_cpu_from_node(unsigned long cpu)
+{
+ int node = numa_cpu_lookup_table[cpu];
+
+ if (cpumask_test_cpu(cpu, node_to_cpumask_map[node])) {
+ cpumask_clear_cpu(cpu, node_to_cpumask_map[node]);
+ pr_debug("removing cpu %lu from node %d\n", cpu, node);
+ } else {
+ pr_warn("Warning: cpu %lu not found in node %d\n", cpu, node);
+ }
+}
+#endif /* CONFIG_HOTPLUG_CPU || CONFIG_PPC_SPLPAR */
+
+static int __associativity_to_nid(const __be32 *associativity,
+ int max_array_sz)
+{
+ int nid;
+ /*
+ * primary_domain_index is 1 based array index.
+ */
+ int index = primary_domain_index - 1;
+
+ if (!numa_enabled || index >= max_array_sz)
+ return NUMA_NO_NODE;
+
+ nid = of_read_number(&associativity[index], 1);
+
+ /* POWER4 LPAR uses 0xffff as invalid node */
+ if (nid == 0xffff || nid >= nr_node_ids)
+ nid = NUMA_NO_NODE;
+ return nid;
+}
+/*
+ * Returns nid in the range [0..nr_node_ids], or -1 if no useful NUMA
+ * info is found.
+ */
+static int associativity_to_nid(const __be32 *associativity)
+{
+ int array_sz = of_read_number(associativity, 1);
+
+ /* Skip the first element in the associativity array */
+ return __associativity_to_nid((associativity + 1), array_sz);
+}
+
+static int __cpu_form2_relative_distance(__be32 *cpu1_assoc, __be32 *cpu2_assoc)
+{
+ int dist;
+ int node1, node2;
+
+ node1 = associativity_to_nid(cpu1_assoc);
+ node2 = associativity_to_nid(cpu2_assoc);
+
+ dist = numa_distance_table[node1][node2];
+ if (dist <= LOCAL_DISTANCE)
+ return 0;
+ else if (dist <= REMOTE_DISTANCE)
+ return 1;
+ else
+ return 2;
+}
+
+static int __cpu_form1_relative_distance(__be32 *cpu1_assoc, __be32 *cpu2_assoc)
+{
+ int dist = 0;
+
+ int i, index;
+
+ for (i = 0; i < distance_ref_points_depth; i++) {
+ index = be32_to_cpu(distance_ref_points[i]);
+ if (cpu1_assoc[index] == cpu2_assoc[index])
+ break;
+ dist++;
+ }
+
+ return dist;
+}
+
+int cpu_relative_distance(__be32 *cpu1_assoc, __be32 *cpu2_assoc)
+{
+ /* We should not get called with FORM0 */
+ VM_WARN_ON(affinity_form == FORM0_AFFINITY);
+ if (affinity_form == FORM1_AFFINITY)
+ return __cpu_form1_relative_distance(cpu1_assoc, cpu2_assoc);
+ return __cpu_form2_relative_distance(cpu1_assoc, cpu2_assoc);
+}
+
+/* must hold reference to node during call */
+static const __be32 *of_get_associativity(struct device_node *dev)
+{
+ return of_get_property(dev, "ibm,associativity", NULL);
+}
+
+int __node_distance(int a, int b)
+{
+ int i;
+ int distance = LOCAL_DISTANCE;
+
+ if (affinity_form == FORM2_AFFINITY)
+ return numa_distance_table[a][b];
+ else if (affinity_form == FORM0_AFFINITY)
+ return ((a == b) ? LOCAL_DISTANCE : REMOTE_DISTANCE);
+
+ for (i = 0; i < distance_ref_points_depth; i++) {
+ if (distance_lookup_table[a][i] == distance_lookup_table[b][i])
+ break;
+
+ /* Double the distance for each NUMA level */
+ distance *= 2;
+ }
+
+ return distance;
+}
+EXPORT_SYMBOL(__node_distance);
+
+/* Returns the nid associated with the given device tree node,
+ * or -1 if not found.
+ */
+static int of_node_to_nid_single(struct device_node *device)
+{
+ int nid = NUMA_NO_NODE;
+ const __be32 *tmp;
+
+ tmp = of_get_associativity(device);
+ if (tmp)
+ nid = associativity_to_nid(tmp);
+ return nid;
+}
+
+/* Walk the device tree upwards, looking for an associativity id */
+int of_node_to_nid(struct device_node *device)
+{
+ int nid = NUMA_NO_NODE;
+
+ of_node_get(device);
+ while (device) {
+ nid = of_node_to_nid_single(device);
+ if (nid != -1)
+ break;
+
+ device = of_get_next_parent(device);
+ }
+ of_node_put(device);
+
+ return nid;
+}
+EXPORT_SYMBOL(of_node_to_nid);
+
+static void __initialize_form1_numa_distance(const __be32 *associativity,
+ int max_array_sz)
+{
+ int i, nid;
+
+ if (affinity_form != FORM1_AFFINITY)
+ return;
+
+ nid = __associativity_to_nid(associativity, max_array_sz);
+ if (nid != NUMA_NO_NODE) {
+ for (i = 0; i < distance_ref_points_depth; i++) {
+ const __be32 *entry;
+ int index = be32_to_cpu(distance_ref_points[i]) - 1;
+
+ /*
+ * broken hierarchy, return with broken distance table
+ */
+ if (WARN(index >= max_array_sz, "Broken ibm,associativity property"))
+ return;
+
+ entry = &associativity[index];
+ distance_lookup_table[nid][i] = of_read_number(entry, 1);
+ }
+ }
+}
+
+static void initialize_form1_numa_distance(const __be32 *associativity)
+{
+ int array_sz;
+
+ array_sz = of_read_number(associativity, 1);
+ /* Skip the first element in the associativity array */
+ __initialize_form1_numa_distance(associativity + 1, array_sz);
+}
+
+/*
+ * Used to update distance information w.r.t newly added node.
+ */
+void update_numa_distance(struct device_node *node)
+{
+ int nid;
+
+ if (affinity_form == FORM0_AFFINITY)
+ return;
+ else if (affinity_form == FORM1_AFFINITY) {
+ const __be32 *associativity;
+
+ associativity = of_get_associativity(node);
+ if (!associativity)
+ return;
+
+ initialize_form1_numa_distance(associativity);
+ return;
+ }
+
+ /* FORM2 affinity */
+ nid = of_node_to_nid_single(node);
+ if (nid == NUMA_NO_NODE)
+ return;
+
+ /*
+ * With FORM2 we expect NUMA distance of all possible NUMA
+ * nodes to be provided during boot.
+ */
+ WARN(numa_distance_table[nid][nid] == -1,
+ "NUMA distance details for node %d not provided\n", nid);
+}
+EXPORT_SYMBOL_GPL(update_numa_distance);
+
+/*
+ * ibm,numa-lookup-index-table= {N, domainid1, domainid2, ..... domainidN}
+ * ibm,numa-distance-table = { N, 1, 2, 4, 5, 1, 6, .... N elements}
+ */
+static void __init initialize_form2_numa_distance_lookup_table(void)
+{
+ int i, j;
+ struct device_node *root;
+ const __u8 *form2_distances;
+ const __be32 *numa_lookup_index;
+ int form2_distances_length;
+ int max_numa_index, distance_index;
+
+ if (firmware_has_feature(FW_FEATURE_OPAL))
+ root = of_find_node_by_path("/ibm,opal");
+ else
+ root = of_find_node_by_path("/rtas");
+ if (!root)
+ root = of_find_node_by_path("/");
+
+ numa_lookup_index = of_get_property(root, "ibm,numa-lookup-index-table", NULL);
+ max_numa_index = of_read_number(&numa_lookup_index[0], 1);
+
+ /* first element of the array is the size and is encode-int */
+ form2_distances = of_get_property(root, "ibm,numa-distance-table", NULL);
+ form2_distances_length = of_read_number((const __be32 *)&form2_distances[0], 1);
+ /* Skip the size which is encoded int */
+ form2_distances += sizeof(__be32);
+
+ pr_debug("form2_distances_len = %d, numa_dist_indexes_len = %d\n",
+ form2_distances_length, max_numa_index);
+
+ for (i = 0; i < max_numa_index; i++)
+ /* +1 skip the max_numa_index in the property */
+ numa_id_index_table[i] = of_read_number(&numa_lookup_index[i + 1], 1);
+
+
+ if (form2_distances_length != max_numa_index * max_numa_index) {
+ WARN(1, "Wrong NUMA distance information\n");
+ form2_distances = NULL; // don't use it
+ }
+ distance_index = 0;
+ for (i = 0; i < max_numa_index; i++) {
+ for (j = 0; j < max_numa_index; j++) {
+ int nodeA = numa_id_index_table[i];
+ int nodeB = numa_id_index_table[j];
+ int dist;
+
+ if (form2_distances)
+ dist = form2_distances[distance_index++];
+ else if (nodeA == nodeB)
+ dist = LOCAL_DISTANCE;
+ else
+ dist = REMOTE_DISTANCE;
+ numa_distance_table[nodeA][nodeB] = dist;
+ pr_debug("dist[%d][%d]=%d ", nodeA, nodeB, dist);
+ }
+ }
+
+ of_node_put(root);
+}
+
+static int __init find_primary_domain_index(void)
+{
+ int index;
+ struct device_node *root;
+
+ /*
+ * Check for which form of affinity.
+ */
+ if (firmware_has_feature(FW_FEATURE_OPAL)) {
+ affinity_form = FORM1_AFFINITY;
+ } else if (firmware_has_feature(FW_FEATURE_FORM2_AFFINITY)) {
+ pr_debug("Using form 2 affinity\n");
+ affinity_form = FORM2_AFFINITY;
+ } else if (firmware_has_feature(FW_FEATURE_FORM1_AFFINITY)) {
+ pr_debug("Using form 1 affinity\n");
+ affinity_form = FORM1_AFFINITY;
+ } else
+ affinity_form = FORM0_AFFINITY;
+
+ if (firmware_has_feature(FW_FEATURE_OPAL))
+ root = of_find_node_by_path("/ibm,opal");
+ else
+ root = of_find_node_by_path("/rtas");
+ if (!root)
+ root = of_find_node_by_path("/");
+
+ /*
+ * This property is a set of 32-bit integers, each representing
+ * an index into the ibm,associativity nodes.
+ *
+ * With form 0 affinity the first integer is for an SMP configuration
+ * (should be all 0's) and the second is for a normal NUMA
+ * configuration. We have only one level of NUMA.
+ *
+ * With form 1 affinity the first integer is the most significant
+ * NUMA boundary and the following are progressively less significant
+ * boundaries. There can be more than one level of NUMA.
+ */
+ distance_ref_points = of_get_property(root,
+ "ibm,associativity-reference-points",
+ &distance_ref_points_depth);
+
+ if (!distance_ref_points) {
+ pr_debug("ibm,associativity-reference-points not found.\n");
+ goto err;
+ }
+
+ distance_ref_points_depth /= sizeof(int);
+ if (affinity_form == FORM0_AFFINITY) {
+ if (distance_ref_points_depth < 2) {
+ pr_warn("short ibm,associativity-reference-points\n");
+ goto err;
+ }
+
+ index = of_read_number(&distance_ref_points[1], 1);
+ } else {
+ /*
+ * Both FORM1 and FORM2 affinity find the primary domain details
+ * at the same offset.
+ */
+ index = of_read_number(distance_ref_points, 1);
+ }
+ /*
+ * Warn and cap if the hardware supports more than
+ * MAX_DISTANCE_REF_POINTS domains.
+ */
+ if (distance_ref_points_depth > MAX_DISTANCE_REF_POINTS) {
+ pr_warn("distance array capped at %d entries\n",
+ MAX_DISTANCE_REF_POINTS);
+ distance_ref_points_depth = MAX_DISTANCE_REF_POINTS;
+ }
+
+ of_node_put(root);
+ return index;
+
+err:
+ of_node_put(root);
+ return -1;
+}
+
+static void __init get_n_mem_cells(int *n_addr_cells, int *n_size_cells)
+{
+ struct device_node *memory = NULL;
+
+ memory = of_find_node_by_type(memory, "memory");
+ if (!memory)
+ panic("numa.c: No memory nodes found!");
+
+ *n_addr_cells = of_n_addr_cells(memory);
+ *n_size_cells = of_n_size_cells(memory);
+ of_node_put(memory);
+}
+
+static unsigned long read_n_cells(int n, const __be32 **buf)
+{
+ unsigned long result = 0;
+
+ while (n--) {
+ result = (result << 32) | of_read_number(*buf, 1);
+ (*buf)++;
+ }
+ return result;
+}
+
+struct assoc_arrays {
+ u32 n_arrays;
+ u32 array_sz;
+ const __be32 *arrays;
+};
+
+/*
+ * Retrieve and validate the list of associativity arrays for drconf
+ * memory from the ibm,associativity-lookup-arrays property of the
+ * device tree..
+ *
+ * The layout of the ibm,associativity-lookup-arrays property is a number N
+ * indicating the number of associativity arrays, followed by a number M
+ * indicating the size of each associativity array, followed by a list
+ * of N associativity arrays.
+ */
+static int of_get_assoc_arrays(struct assoc_arrays *aa)
+{
+ struct device_node *memory;
+ const __be32 *prop;
+ u32 len;
+
+ memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
+ if (!memory)
+ return -1;
+
+ prop = of_get_property(memory, "ibm,associativity-lookup-arrays", &len);
+ if (!prop || len < 2 * sizeof(unsigned int)) {
+ of_node_put(memory);
+ return -1;
+ }
+
+ aa->n_arrays = of_read_number(prop++, 1);
+ aa->array_sz = of_read_number(prop++, 1);
+
+ of_node_put(memory);
+
+ /* Now that we know the number of arrays and size of each array,
+ * revalidate the size of the property read in.
+ */
+ if (len < (aa->n_arrays * aa->array_sz + 2) * sizeof(unsigned int))
+ return -1;
+
+ aa->arrays = prop;
+ return 0;
+}
+
+static int __init get_nid_and_numa_distance(struct drmem_lmb *lmb)
+{
+ struct assoc_arrays aa = { .arrays = NULL };
+ int default_nid = NUMA_NO_NODE;
+ int nid = default_nid;
+ int rc, index;
+
+ if ((primary_domain_index < 0) || !numa_enabled)
+ return default_nid;
+
+ rc = of_get_assoc_arrays(&aa);
+ if (rc)
+ return default_nid;
+
+ if (primary_domain_index <= aa.array_sz &&
+ !(lmb->flags & DRCONF_MEM_AI_INVALID) && lmb->aa_index < aa.n_arrays) {
+ const __be32 *associativity;
+
+ index = lmb->aa_index * aa.array_sz;
+ associativity = &aa.arrays[index];
+ nid = __associativity_to_nid(associativity, aa.array_sz);
+ if (nid > 0 && affinity_form == FORM1_AFFINITY) {
+ /*
+ * lookup array associativity entries have
+ * no length of the array as the first element.
+ */
+ __initialize_form1_numa_distance(associativity, aa.array_sz);
+ }
+ }
+ return nid;
+}
+
+/*
+ * This is like of_node_to_nid_single() for memory represented in the
+ * ibm,dynamic-reconfiguration-memory node.
+ */
+int of_drconf_to_nid_single(struct drmem_lmb *lmb)
+{
+ struct assoc_arrays aa = { .arrays = NULL };
+ int default_nid = NUMA_NO_NODE;
+ int nid = default_nid;
+ int rc, index;
+
+ if ((primary_domain_index < 0) || !numa_enabled)
+ return default_nid;
+
+ rc = of_get_assoc_arrays(&aa);
+ if (rc)
+ return default_nid;
+
+ if (primary_domain_index <= aa.array_sz &&
+ !(lmb->flags & DRCONF_MEM_AI_INVALID) && lmb->aa_index < aa.n_arrays) {
+ const __be32 *associativity;
+
+ index = lmb->aa_index * aa.array_sz;
+ associativity = &aa.arrays[index];
+ nid = __associativity_to_nid(associativity, aa.array_sz);
+ }
+ return nid;
+}
+
+#ifdef CONFIG_PPC_SPLPAR
+
+static int __vphn_get_associativity(long lcpu, __be32 *associativity)
+{
+ long rc, hwid;
+
+ /*
+ * On a shared lpar, device tree will not have node associativity.
+ * At this time lppaca, or its __old_status field may not be
+ * updated. Hence kernel cannot detect if its on a shared lpar. So
+ * request an explicit associativity irrespective of whether the
+ * lpar is shared or dedicated. Use the device tree property as a
+ * fallback. cpu_to_phys_id is only valid between
+ * smp_setup_cpu_maps() and smp_setup_pacas().
+ */
+ if (firmware_has_feature(FW_FEATURE_VPHN)) {
+ if (cpu_to_phys_id)
+ hwid = cpu_to_phys_id[lcpu];
+ else
+ hwid = get_hard_smp_processor_id(lcpu);
+
+ rc = hcall_vphn(hwid, VPHN_FLAG_VCPU, associativity);
+ if (rc == H_SUCCESS)
+ return 0;
+ }
+
+ return -1;
+}
+
+static int vphn_get_nid(long lcpu)
+{
+ __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
+
+
+ if (!__vphn_get_associativity(lcpu, associativity))
+ return associativity_to_nid(associativity);
+
+ return NUMA_NO_NODE;
+
+}
+#else
+
+static int __vphn_get_associativity(long lcpu, __be32 *associativity)
+{
+ return -1;
+}
+
+static int vphn_get_nid(long unused)
+{
+ return NUMA_NO_NODE;
+}
+#endif /* CONFIG_PPC_SPLPAR */
+
+/*
+ * Figure out to which domain a cpu belongs and stick it there.
+ * Return the id of the domain used.
+ */
+static int numa_setup_cpu(unsigned long lcpu)
+{
+ struct device_node *cpu;
+ int fcpu = cpu_first_thread_sibling(lcpu);
+ int nid = NUMA_NO_NODE;
+
+ if (!cpu_present(lcpu)) {
+ set_cpu_numa_node(lcpu, first_online_node);
+ return first_online_node;
+ }
+
+ /*
+ * If a valid cpu-to-node mapping is already available, use it
+ * directly instead of querying the firmware, since it represents
+ * the most recent mapping notified to us by the platform (eg: VPHN).
+ * Since cpu_to_node binding remains the same for all threads in the
+ * core. If a valid cpu-to-node mapping is already available, for
+ * the first thread in the core, use it.
+ */
+ nid = numa_cpu_lookup_table[fcpu];
+ if (nid >= 0) {
+ map_cpu_to_node(lcpu, nid);
+ return nid;
+ }
+
+ nid = vphn_get_nid(lcpu);
+ if (nid != NUMA_NO_NODE)
+ goto out_present;
+
+ cpu = of_get_cpu_node(lcpu, NULL);
+
+ if (!cpu) {
+ WARN_ON(1);
+ if (cpu_present(lcpu))
+ goto out_present;
+ else
+ goto out;
+ }
+
+ nid = of_node_to_nid_single(cpu);
+ of_node_put(cpu);
+
+out_present:
+ if (nid < 0 || !node_possible(nid))
+ nid = first_online_node;
+
+ /*
+ * Update for the first thread of the core. All threads of a core
+ * have to be part of the same node. This not only avoids querying
+ * for every other thread in the core, but always avoids a case
+ * where virtual node associativity change causes subsequent threads
+ * of a core to be associated with different nid. However if first
+ * thread is already online, expect it to have a valid mapping.
+ */
+ if (fcpu != lcpu) {
+ WARN_ON(cpu_online(fcpu));
+ map_cpu_to_node(fcpu, nid);
+ }
+
+ map_cpu_to_node(lcpu, nid);
+out:
+ return nid;
+}
+
+static void verify_cpu_node_mapping(int cpu, int node)
+{
+ int base, sibling, i;
+
+ /* Verify that all the threads in the core belong to the same node */
+ base = cpu_first_thread_sibling(cpu);
+
+ for (i = 0; i < threads_per_core; i++) {
+ sibling = base + i;
+
+ if (sibling == cpu || cpu_is_offline(sibling))
+ continue;
+
+ if (cpu_to_node(sibling) != node) {
+ WARN(1, "CPU thread siblings %d and %d don't belong"
+ " to the same node!\n", cpu, sibling);
+ break;
+ }
+ }
+}
+
+/* Must run before sched domains notifier. */
+static int ppc_numa_cpu_prepare(unsigned int cpu)
+{
+ int nid;
+
+ nid = numa_setup_cpu(cpu);
+ verify_cpu_node_mapping(cpu, nid);
+ return 0;
+}
+
+static int ppc_numa_cpu_dead(unsigned int cpu)
+{
+ return 0;
+}
+
+/*
+ * Check and possibly modify a memory region to enforce the memory limit.
+ *
+ * Returns the size the region should have to enforce the memory limit.
+ * This will either be the original value of size, a truncated value,
+ * or zero. If the returned value of size is 0 the region should be
+ * discarded as it lies wholly above the memory limit.
+ */
+static unsigned long __init numa_enforce_memory_limit(unsigned long start,
+ unsigned long size)
+{
+ /*
+ * We use memblock_end_of_DRAM() in here instead of memory_limit because
+ * we've already adjusted it for the limit and it takes care of
+ * having memory holes below the limit. Also, in the case of
+ * iommu_is_off, memory_limit is not set but is implicitly enforced.
+ */
+
+ if (start + size <= memblock_end_of_DRAM())
+ return size;
+
+ if (start >= memblock_end_of_DRAM())
+ return 0;
+
+ return memblock_end_of_DRAM() - start;
+}
+
+/*
+ * Reads the counter for a given entry in
+ * linux,drconf-usable-memory property
+ */
+static inline int __init read_usm_ranges(const __be32 **usm)
+{
+ /*
+ * For each lmb in ibm,dynamic-memory a corresponding
+ * entry in linux,drconf-usable-memory property contains
+ * a counter followed by that many (base, size) duple.
+ * read the counter from linux,drconf-usable-memory
+ */
+ return read_n_cells(n_mem_size_cells, usm);
+}
+
+/*
+ * Extract NUMA information from the ibm,dynamic-reconfiguration-memory
+ * node. This assumes n_mem_{addr,size}_cells have been set.
+ */
+static int __init numa_setup_drmem_lmb(struct drmem_lmb *lmb,
+ const __be32 **usm,
+ void *data)
+{
+ unsigned int ranges, is_kexec_kdump = 0;
+ unsigned long base, size, sz;
+ int nid;
+
+ /*
+ * Skip this block if the reserved bit is set in flags (0x80)
+ * or if the block is not assigned to this partition (0x8)
+ */
+ if ((lmb->flags & DRCONF_MEM_RESERVED)
+ || !(lmb->flags & DRCONF_MEM_ASSIGNED))
+ return 0;
+
+ if (*usm)
+ is_kexec_kdump = 1;
+
+ base = lmb->base_addr;
+ size = drmem_lmb_size();
+ ranges = 1;
+
+ if (is_kexec_kdump) {
+ ranges = read_usm_ranges(usm);
+ if (!ranges) /* there are no (base, size) duple */
+ return 0;
+ }
+
+ do {
+ if (is_kexec_kdump) {
+ base = read_n_cells(n_mem_addr_cells, usm);
+ size = read_n_cells(n_mem_size_cells, usm);
+ }
+
+ nid = get_nid_and_numa_distance(lmb);
+ fake_numa_create_new_node(((base + size) >> PAGE_SHIFT),
+ &nid);
+ node_set_online(nid);
+ sz = numa_enforce_memory_limit(base, size);
+ if (sz)
+ memblock_set_node(base, sz, &memblock.memory, nid);
+ } while (--ranges);
+
+ return 0;
+}
+
+static int __init parse_numa_properties(void)
+{
+ struct device_node *memory;
+ int default_nid = 0;
+ unsigned long i;
+ const __be32 *associativity;
+
+ if (numa_enabled == 0) {
+ pr_warn("disabled by user\n");
+ return -1;
+ }
+
+ primary_domain_index = find_primary_domain_index();
+
+ if (primary_domain_index < 0) {
+ /*
+ * if we fail to parse primary_domain_index from device tree
+ * mark the numa disabled, boot with numa disabled.
+ */
+ numa_enabled = false;
+ return primary_domain_index;
+ }
+
+ pr_debug("associativity depth for CPU/Memory: %d\n", primary_domain_index);
+
+ /*
+ * If it is FORM2 initialize the distance table here.
+ */
+ if (affinity_form == FORM2_AFFINITY)
+ initialize_form2_numa_distance_lookup_table();
+
+ /*
+ * Even though we connect cpus to numa domains later in SMP
+ * init, we need to know the node ids now. This is because
+ * each node to be onlined must have NODE_DATA etc backing it.
+ */
+ for_each_present_cpu(i) {
+ __be32 vphn_assoc[VPHN_ASSOC_BUFSIZE];
+ struct device_node *cpu;
+ int nid = NUMA_NO_NODE;
+
+ memset(vphn_assoc, 0, VPHN_ASSOC_BUFSIZE * sizeof(__be32));
+
+ if (__vphn_get_associativity(i, vphn_assoc) == 0) {
+ nid = associativity_to_nid(vphn_assoc);
+ initialize_form1_numa_distance(vphn_assoc);
+ } else {
+
+ /*
+ * Don't fall back to default_nid yet -- we will plug
+ * cpus into nodes once the memory scan has discovered
+ * the topology.
+ */
+ cpu = of_get_cpu_node(i, NULL);
+ BUG_ON(!cpu);
+
+ associativity = of_get_associativity(cpu);
+ if (associativity) {
+ nid = associativity_to_nid(associativity);
+ initialize_form1_numa_distance(associativity);
+ }
+ of_node_put(cpu);
+ }
+
+ /* node_set_online() is an UB if 'nid' is negative */
+ if (likely(nid >= 0))
+ node_set_online(nid);
+ }
+
+ get_n_mem_cells(&n_mem_addr_cells, &n_mem_size_cells);
+
+ for_each_node_by_type(memory, "memory") {
+ unsigned long start;
+ unsigned long size;
+ int nid;
+ int ranges;
+ const __be32 *memcell_buf;
+ unsigned int len;
+
+ memcell_buf = of_get_property(memory,
+ "linux,usable-memory", &len);
+ if (!memcell_buf || len <= 0)
+ memcell_buf = of_get_property(memory, "reg", &len);
+ if (!memcell_buf || len <= 0)
+ continue;
+
+ /* ranges in cell */
+ ranges = (len >> 2) / (n_mem_addr_cells + n_mem_size_cells);
+new_range:
+ /* these are order-sensitive, and modify the buffer pointer */
+ start = read_n_cells(n_mem_addr_cells, &memcell_buf);
+ size = read_n_cells(n_mem_size_cells, &memcell_buf);
+
+ /*
+ * Assumption: either all memory nodes or none will
+ * have associativity properties. If none, then
+ * everything goes to default_nid.
+ */
+ associativity = of_get_associativity(memory);
+ if (associativity) {
+ nid = associativity_to_nid(associativity);
+ initialize_form1_numa_distance(associativity);
+ } else
+ nid = default_nid;
+
+ fake_numa_create_new_node(((start + size) >> PAGE_SHIFT), &nid);
+ node_set_online(nid);
+
+ size = numa_enforce_memory_limit(start, size);
+ if (size)
+ memblock_set_node(start, size, &memblock.memory, nid);
+
+ if (--ranges)
+ goto new_range;
+ }
+
+ /*
+ * Now do the same thing for each MEMBLOCK listed in the
+ * ibm,dynamic-memory property in the
+ * ibm,dynamic-reconfiguration-memory node.
+ */
+ memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
+ if (memory) {
+ walk_drmem_lmbs(memory, NULL, numa_setup_drmem_lmb);
+ of_node_put(memory);
+ }
+
+ return 0;
+}
+
+static void __init setup_nonnuma(void)
+{
+ unsigned long top_of_ram = memblock_end_of_DRAM();
+ unsigned long total_ram = memblock_phys_mem_size();
+ unsigned long start_pfn, end_pfn;
+ unsigned int nid = 0;
+ int i;
+
+ pr_debug("Top of RAM: 0x%lx, Total RAM: 0x%lx\n", top_of_ram, total_ram);
+ pr_debug("Memory hole size: %ldMB\n", (top_of_ram - total_ram) >> 20);
+
+ for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
+ fake_numa_create_new_node(end_pfn, &nid);
+ memblock_set_node(PFN_PHYS(start_pfn),
+ PFN_PHYS(end_pfn - start_pfn),
+ &memblock.memory, nid);
+ node_set_online(nid);
+ }
+}
+
+void __init dump_numa_cpu_topology(void)
+{
+ unsigned int node;
+ unsigned int cpu, count;
+
+ if (!numa_enabled)
+ return;
+
+ for_each_online_node(node) {
+ pr_info("Node %d CPUs:", node);
+
+ count = 0;
+ /*
+ * If we used a CPU iterator here we would miss printing
+ * the holes in the cpumap.
+ */
+ for (cpu = 0; cpu < nr_cpu_ids; cpu++) {
+ if (cpumask_test_cpu(cpu,
+ node_to_cpumask_map[node])) {
+ if (count == 0)
+ pr_cont(" %u", cpu);
+ ++count;
+ } else {
+ if (count > 1)
+ pr_cont("-%u", cpu - 1);
+ count = 0;
+ }
+ }
+
+ if (count > 1)
+ pr_cont("-%u", nr_cpu_ids - 1);
+ pr_cont("\n");
+ }
+}
+
+/* Initialize NODE_DATA for a node on the local memory */
+static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
+{
+ u64 spanned_pages = end_pfn - start_pfn;
+ const size_t nd_size = roundup(sizeof(pg_data_t), SMP_CACHE_BYTES);
+ u64 nd_pa;
+ void *nd;
+ int tnid;
+
+ nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
+ if (!nd_pa)
+ panic("Cannot allocate %zu bytes for node %d data\n",
+ nd_size, nid);
+
+ nd = __va(nd_pa);
+
+ /* report and initialize */
+ pr_info(" NODE_DATA [mem %#010Lx-%#010Lx]\n",
+ nd_pa, nd_pa + nd_size - 1);
+ tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
+ if (tnid != nid)
+ pr_info(" NODE_DATA(%d) on node %d\n", nid, tnid);
+
+ node_data[nid] = nd;
+ memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
+ NODE_DATA(nid)->node_id = nid;
+ NODE_DATA(nid)->node_start_pfn = start_pfn;
+ NODE_DATA(nid)->node_spanned_pages = spanned_pages;
+}
+
+static void __init find_possible_nodes(void)
+{
+ struct device_node *rtas;
+ const __be32 *domains = NULL;
+ int prop_length, max_nodes;
+ u32 i;
+
+ if (!numa_enabled)
+ return;
+
+ rtas = of_find_node_by_path("/rtas");
+ if (!rtas)
+ return;
+
+ /*
+ * ibm,current-associativity-domains is a fairly recent property. If
+ * it doesn't exist, then fallback on ibm,max-associativity-domains.
+ * Current denotes what the platform can support compared to max
+ * which denotes what the Hypervisor can support.
+ *
+ * If the LPAR is migratable, new nodes might be activated after a LPM,
+ * so we should consider the max number in that case.
+ */
+ if (!of_get_property(of_root, "ibm,migratable-partition", NULL))
+ domains = of_get_property(rtas,
+ "ibm,current-associativity-domains",
+ &prop_length);
+ if (!domains) {
+ domains = of_get_property(rtas, "ibm,max-associativity-domains",
+ &prop_length);
+ if (!domains)
+ goto out;
+ }
+
+ max_nodes = of_read_number(&domains[primary_domain_index], 1);
+ pr_info("Partition configured for %d NUMA nodes.\n", max_nodes);
+
+ for (i = 0; i < max_nodes; i++) {
+ if (!node_possible(i))
+ node_set(i, node_possible_map);
+ }
+
+ prop_length /= sizeof(int);
+ if (prop_length > primary_domain_index + 2)
+ coregroup_enabled = 1;
+
+out:
+ of_node_put(rtas);
+}
+
+void __init mem_topology_setup(void)
+{
+ int cpu;
+
+ max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
+ min_low_pfn = MEMORY_START >> PAGE_SHIFT;
+
+ /*
+ * Linux/mm assumes node 0 to be online at boot. However this is not
+ * true on PowerPC, where node 0 is similar to any other node, it
+ * could be cpuless, memoryless node. So force node 0 to be offline
+ * for now. This will prevent cpuless, memoryless node 0 showing up
+ * unnecessarily as online. If a node has cpus or memory that need
+ * to be online, then node will anyway be marked online.
+ */
+ node_set_offline(0);
+
+ if (parse_numa_properties())
+ setup_nonnuma();
+
+ /*
+ * Modify the set of possible NUMA nodes to reflect information
+ * available about the set of online nodes, and the set of nodes
+ * that we expect to make use of for this platform's affinity
+ * calculations.
+ */
+ nodes_and(node_possible_map, node_possible_map, node_online_map);
+
+ find_possible_nodes();
+
+ setup_node_to_cpumask_map();
+
+ reset_numa_cpu_lookup_table();
+
+ for_each_possible_cpu(cpu) {
+ /*
+ * Powerpc with CONFIG_NUMA always used to have a node 0,
+ * even if it was memoryless or cpuless. For all cpus that
+ * are possible but not present, cpu_to_node() would point
+ * to node 0. To remove a cpuless, memoryless dummy node,
+ * powerpc need to make sure all possible but not present
+ * cpu_to_node are set to a proper node.
+ */
+ numa_setup_cpu(cpu);
+ }
+}
+
+void __init initmem_init(void)
+{
+ int nid;
+
+ memblock_dump_all();
+
+ for_each_online_node(nid) {
+ unsigned long start_pfn, end_pfn;
+
+ get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
+ setup_node_data(nid, start_pfn, end_pfn);
+ }
+
+ sparse_init();
+
+ /*
+ * We need the numa_cpu_lookup_table to be accurate for all CPUs,
+ * even before we online them, so that we can use cpu_to_{node,mem}
+ * early in boot, cf. smp_prepare_cpus().
+ * _nocalls() + manual invocation is used because cpuhp is not yet
+ * initialized for the boot CPU.
+ */
+ cpuhp_setup_state_nocalls(CPUHP_POWER_NUMA_PREPARE, "powerpc/numa:prepare",
+ ppc_numa_cpu_prepare, ppc_numa_cpu_dead);
+}
+
+static int __init early_numa(char *p)
+{
+ if (!p)
+ return 0;
+
+ if (strstr(p, "off"))
+ numa_enabled = 0;
+
+ p = strstr(p, "fake=");
+ if (p)
+ cmdline = p + strlen("fake=");
+
+ return 0;
+}
+early_param("numa", early_numa);
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+/*
+ * Find the node associated with a hot added memory section for
+ * memory represented in the device tree by the property
+ * ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory.
+ */
+static int hot_add_drconf_scn_to_nid(unsigned long scn_addr)
+{
+ struct drmem_lmb *lmb;
+ unsigned long lmb_size;
+ int nid = NUMA_NO_NODE;
+
+ lmb_size = drmem_lmb_size();
+
+ for_each_drmem_lmb(lmb) {
+ /* skip this block if it is reserved or not assigned to
+ * this partition */
+ if ((lmb->flags & DRCONF_MEM_RESERVED)
+ || !(lmb->flags & DRCONF_MEM_ASSIGNED))
+ continue;
+
+ if ((scn_addr < lmb->base_addr)
+ || (scn_addr >= (lmb->base_addr + lmb_size)))
+ continue;
+
+ nid = of_drconf_to_nid_single(lmb);
+ break;
+ }
+
+ return nid;
+}
+
+/*
+ * Find the node associated with a hot added memory section for memory
+ * represented in the device tree as a node (i.e. memory@XXXX) for
+ * each memblock.
+ */
+static int hot_add_node_scn_to_nid(unsigned long scn_addr)
+{
+ struct device_node *memory;
+ int nid = NUMA_NO_NODE;
+
+ for_each_node_by_type(memory, "memory") {
+ unsigned long start, size;
+ int ranges;
+ const __be32 *memcell_buf;
+ unsigned int len;
+
+ memcell_buf = of_get_property(memory, "reg", &len);
+ if (!memcell_buf || len <= 0)
+ continue;
+
+ /* ranges in cell */
+ ranges = (len >> 2) / (n_mem_addr_cells + n_mem_size_cells);
+
+ while (ranges--) {
+ start = read_n_cells(n_mem_addr_cells, &memcell_buf);
+ size = read_n_cells(n_mem_size_cells, &memcell_buf);
+
+ if ((scn_addr < start) || (scn_addr >= (start + size)))
+ continue;
+
+ nid = of_node_to_nid_single(memory);
+ break;
+ }
+
+ if (nid >= 0)
+ break;
+ }
+
+ of_node_put(memory);
+
+ return nid;
+}
+
+/*
+ * Find the node associated with a hot added memory section. Section
+ * corresponds to a SPARSEMEM section, not an MEMBLOCK. It is assumed that
+ * sections are fully contained within a single MEMBLOCK.
+ */
+int hot_add_scn_to_nid(unsigned long scn_addr)
+{
+ struct device_node *memory = NULL;
+ int nid;
+
+ if (!numa_enabled)
+ return first_online_node;
+
+ memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
+ if (memory) {
+ nid = hot_add_drconf_scn_to_nid(scn_addr);
+ of_node_put(memory);
+ } else {
+ nid = hot_add_node_scn_to_nid(scn_addr);
+ }
+
+ if (nid < 0 || !node_possible(nid))
+ nid = first_online_node;
+
+ return nid;
+}
+
+static u64 hot_add_drconf_memory_max(void)
+{
+ struct device_node *memory = NULL;
+ struct device_node *dn = NULL;
+ const __be64 *lrdr = NULL;
+
+ dn = of_find_node_by_path("/rtas");
+ if (dn) {
+ lrdr = of_get_property(dn, "ibm,lrdr-capacity", NULL);
+ of_node_put(dn);
+ if (lrdr)
+ return be64_to_cpup(lrdr);
+ }
+
+ memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
+ if (memory) {
+ of_node_put(memory);
+ return drmem_lmb_memory_max();
+ }
+ return 0;
+}
+
+/*
+ * memory_hotplug_max - return max address of memory that may be added
+ *
+ * This is currently only used on systems that support drconfig memory
+ * hotplug.
+ */
+u64 memory_hotplug_max(void)
+{
+ return max(hot_add_drconf_memory_max(), memblock_end_of_DRAM());
+}
+#endif /* CONFIG_MEMORY_HOTPLUG */
+
+/* Virtual Processor Home Node (VPHN) support */
+#ifdef CONFIG_PPC_SPLPAR
+static int topology_inited;
+
+/*
+ * Retrieve the new associativity information for a virtual processor's
+ * home node.
+ */
+static long vphn_get_associativity(unsigned long cpu,
+ __be32 *associativity)
+{
+ long rc;
+
+ rc = hcall_vphn(get_hard_smp_processor_id(cpu),
+ VPHN_FLAG_VCPU, associativity);
+
+ switch (rc) {
+ case H_SUCCESS:
+ pr_debug("VPHN hcall succeeded. Reset polling...\n");
+ goto out;
+
+ case H_FUNCTION:
+ pr_err_ratelimited("VPHN unsupported. Disabling polling...\n");
+ break;
+ case H_HARDWARE:
+ pr_err_ratelimited("hcall_vphn() experienced a hardware fault "
+ "preventing VPHN. Disabling polling...\n");
+ break;
+ case H_PARAMETER:
+ pr_err_ratelimited("hcall_vphn() was passed an invalid parameter. "
+ "Disabling polling...\n");
+ break;
+ default:
+ pr_err_ratelimited("hcall_vphn() returned %ld. Disabling polling...\n"
+ , rc);
+ break;
+ }
+out:
+ return rc;
+}
+
+void find_and_update_cpu_nid(int cpu)
+{
+ __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
+ int new_nid;
+
+ /* Use associativity from first thread for all siblings */
+ if (vphn_get_associativity(cpu, associativity))
+ return;
+
+ /* Do not have previous associativity, so find it now. */
+ new_nid = associativity_to_nid(associativity);
+
+ if (new_nid < 0 || !node_possible(new_nid))
+ new_nid = first_online_node;
+ else
+ // Associate node <-> cpu, so cpu_up() calls
+ // try_online_node() on the right node.
+ set_cpu_numa_node(cpu, new_nid);
+
+ pr_debug("%s:%d cpu %d nid %d\n", __func__, __LINE__, cpu, new_nid);
+}
+
+int cpu_to_coregroup_id(int cpu)
+{
+ __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
+ int index;
+
+ if (cpu < 0 || cpu > nr_cpu_ids)
+ return -1;
+
+ if (!coregroup_enabled)
+ goto out;
+
+ if (!firmware_has_feature(FW_FEATURE_VPHN))
+ goto out;
+
+ if (vphn_get_associativity(cpu, associativity))
+ goto out;
+
+ index = of_read_number(associativity, 1);
+ if (index > primary_domain_index + 1)
+ return of_read_number(&associativity[index - 1], 1);
+
+out:
+ return cpu_to_core_id(cpu);
+}
+
+static int topology_update_init(void)
+{
+ topology_inited = 1;
+ return 0;
+}
+device_initcall(topology_update_init);
+#endif /* CONFIG_PPC_SPLPAR */