1 files changed, 263 insertions, 17 deletions

diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c
index 54676e3d82dd..de5f8c018333 100644
--- a/drivers/acpi/pptt.c
+++ b/drivers/acpi/pptt.c
@@ -21,6 +21,25 @@
 #include <linux/cacheinfo.h>
 #include <acpi/processor.h>
 
+/*
+ * The acpi_pptt_cache_v1 in actbl2.h, which is imported from acpica,
+ * only contains the cache_id field rather than all the fields of the
+ * Cache Type Structure. Use this alternative structure until it is
+ * resolved in acpica.
+ */
+struct acpi_pptt_cache_v1_full {
+	struct acpi_subtable_header header;
+	u16 reserved;
+	u32 flags;
+	u32 next_level_of_cache;
+	u32 size;
+	u32 number_of_sets;
+	u8 associativity;
+	u8 attributes;
+	u16 line_size;
+	u32 cache_id;
+} __packed;
+
 static struct acpi_subtable_header *fetch_pptt_subtable(struct acpi_table_header *table_hdr,
 							u32 pptt_ref)
 {
@@ -56,6 +75,18 @@ static struct acpi_pptt_cache *fetch_pptt_cache(struct acpi_table_header *table_
 	return (struct acpi_pptt_cache *)fetch_pptt_subtable(table_hdr, pptt_ref);
 }
 
+static struct acpi_pptt_cache_v1_full *upgrade_pptt_cache(struct acpi_pptt_cache *cache)
+{
+	if (cache->header.length < sizeof(struct acpi_pptt_cache_v1_full))
+		return NULL;
+
+	/* No use for v1 if the only additional field is invalid */
+	if (!(cache->flags & ACPI_PPTT_CACHE_ID_VALID))
+		return NULL;
+
+	return (struct acpi_pptt_cache_v1_full *)cache;
+}
+
 static struct acpi_subtable_header *acpi_get_pptt_resource(struct acpi_table_header *table_hdr,
 							   struct acpi_pptt_processor *node,
 							   int resource)
@@ -177,14 +208,14 @@ acpi_find_cache_level(struct acpi_table_header *table_hdr,
 }
 
 /**
- * acpi_count_levels() - Given a PPTT table, and a CPU node, count the cache
- * levels and split cache levels (data/instruction).
+ * acpi_count_levels() - Given a PPTT table, and a CPU node, count the
+ * total number of levels and split cache levels (data/instruction).
  * @table_hdr: Pointer to the head of the PPTT table
  * @cpu_node: processor node we wish to count caches for
- * @levels: Number of levels if success.
  * @split_levels:	Number of split cache levels (data/instruction) if
  *			success. Can by NULL.
  *
+ * Return: number of levels.
  * Given a processor node containing a processing unit, walk into it and count
  * how many levels exist solely for it, and then walk up each level until we hit
  * the root node (ignore the package level because it may be possible to have
@@ -192,14 +223,18 @@ acpi_find_cache_level(struct acpi_table_header *table_hdr,
  * split cache levels (data/instruction) that exist at each level on the way
  * up.
  */
-static void acpi_count_levels(struct acpi_table_header *table_hdr,
-			      struct acpi_pptt_processor *cpu_node,
-			      unsigned int *levels, unsigned int *split_levels)
+static int acpi_count_levels(struct acpi_table_header *table_hdr,
+			     struct acpi_pptt_processor *cpu_node,
+			     unsigned int *split_levels)
 {
+	int current_level = 0;
+
 	do {
-		acpi_find_cache_level(table_hdr, cpu_node, levels, split_levels, 0, 0);
+		acpi_find_cache_level(table_hdr, cpu_node, &current_level, split_levels, 0, 0);
 		cpu_node = fetch_pptt_node(table_hdr, cpu_node->parent);
 	} while (cpu_node);
+
+	return current_level;
 }
 
 /**
@@ -351,7 +386,6 @@ static struct acpi_pptt_cache *acpi_find_cache_node(struct acpi_table_header *ta
  * @this_leaf: Kernel cache info structure being updated
  * @found_cache: The PPTT node describing this cache instance
  * @cpu_node: A unique reference to describe this cache instance
- * @revision: The revision of the PPTT table
  *
  * The ACPI spec implies that the fields in the cache structures are used to
  * extend and correct the information probed from the hardware. Lets only
@@ -361,10 +395,9 @@ static struct acpi_pptt_cache *acpi_find_cache_node(struct acpi_table_header *ta
  */
 static void update_cache_properties(struct cacheinfo *this_leaf,
 				    struct acpi_pptt_cache *found_cache,
-				    struct acpi_pptt_processor *cpu_node,
-				    u8 revision)
+				    struct acpi_pptt_processor *cpu_node)
 {
-	struct acpi_pptt_cache_v1* found_cache_v1;
+	struct acpi_pptt_cache_v1_full *found_cache_v1;
 
 	this_leaf->fw_token = cpu_node;
 	if (found_cache->flags & ACPI_PPTT_SIZE_PROPERTY_VALID)
@@ -414,9 +447,8 @@ static void update_cache_properties(struct cacheinfo *this_leaf,
 	    found_cache->flags & ACPI_PPTT_CACHE_TYPE_VALID)
 		this_leaf->type = CACHE_TYPE_UNIFIED;
 
-	if (revision >= 3 && (found_cache->flags & ACPI_PPTT_CACHE_ID_VALID)) {
-		found_cache_v1 = ACPI_ADD_PTR(struct acpi_pptt_cache_v1,
-	                                      found_cache, sizeof(struct acpi_pptt_cache));
+	found_cache_v1 = upgrade_pptt_cache(found_cache);
+	if (found_cache_v1) {
 		this_leaf->id = found_cache_v1->cache_id;
 		this_leaf->attributes |= CACHE_ID;
 	}
@@ -441,8 +473,7 @@ static void cache_setup_acpi_cpu(struct acpi_table_header *table,
 		pr_debug("found = %p %p\n", found_cache, cpu_node);
 		if (found_cache)
 			update_cache_properties(this_leaf, found_cache,
-						ACPI_TO_POINTER(ACPI_PTR_DIFF(cpu_node, table)),
-						table->revision);
+						ACPI_TO_POINTER(ACPI_PTR_DIFF(cpu_node, table)));
 
 		index++;
 	}
@@ -645,7 +676,7 @@ int acpi_get_cache_info(unsigned int cpu, unsigned int *levels,
 	if (!cpu_node)
 		return -ENOENT;
 
-	acpi_count_levels(table, cpu_node, levels, split_levels);
+	*levels = acpi_count_levels(table, cpu_node, split_levels);
 
 	pr_debug("Cache Setup: last_level=%d split_levels=%d\n",
 		 *levels, split_levels ? *split_levels : -1);
@@ -817,3 +848,218 @@ int find_acpi_cpu_topology_hetero_id(unsigned int cpu)
 	return find_acpi_cpu_topology_tag(cpu, PPTT_ABORT_PACKAGE,
 					  ACPI_PPTT_ACPI_IDENTICAL);
 }
+
+/**
+ * acpi_pptt_get_child_cpus() - Find all the CPUs below a PPTT
+ * processor hierarchy node
+ *
+ * @table_hdr:		A reference to the PPTT table
+ * @parent_node:	A pointer to the processor hierarchy node in the
+ *			table_hdr
+ * @cpus:		A cpumask to fill with the CPUs below @parent_node
+ *
+ * Walks up the PPTT from every possible CPU to find if the provided
+ * @parent_node is a parent of this CPU.
+ */
+static void acpi_pptt_get_child_cpus(struct acpi_table_header *table_hdr,
+				     struct acpi_pptt_processor *parent_node,
+				     cpumask_t *cpus)
+{
+	struct acpi_pptt_processor *cpu_node;
+	u32 acpi_id;
+	int cpu;
+
+	cpumask_clear(cpus);
+
+	for_each_possible_cpu(cpu) {
+		acpi_id = get_acpi_id_for_cpu(cpu);
+		cpu_node = acpi_find_processor_node(table_hdr, acpi_id);
+
+		while (cpu_node) {
+			if (cpu_node == parent_node) {
+				cpumask_set_cpu(cpu, cpus);
+				break;
+			}
+			cpu_node = fetch_pptt_node(table_hdr, cpu_node->parent);
+		}
+	}
+}
+
+/**
+ * acpi_pptt_get_cpus_from_container() - Populate a cpumask with all CPUs in a
+ *                                       processor container
+ * @acpi_cpu_id:	The UID of the processor container
+ * @cpus:		The resulting CPU mask
+ *
+ * Find the specified Processor Container, and fill @cpus with all the cpus
+ * below it.
+ *
+ * Not all 'Processor Hierarchy' entries in the PPTT are either a CPU
+ * or a Processor Container, they may exist purely to describe a
+ * Private resource. CPUs have to be leaves, so a Processor Container
+ * is a non-leaf that has the 'ACPI Processor ID valid' flag set.
+ */
+void acpi_pptt_get_cpus_from_container(u32 acpi_cpu_id, cpumask_t *cpus)
+{
+	struct acpi_table_header *table_hdr;
+	struct acpi_subtable_header *entry;
+	unsigned long table_end;
+	u32 proc_sz;
+
+	cpumask_clear(cpus);
+
+	table_hdr = acpi_get_pptt();
+	if (!table_hdr)
+		return;
+
+	table_end = (unsigned long)table_hdr + table_hdr->length;
+	entry = ACPI_ADD_PTR(struct acpi_subtable_header, table_hdr,
+			     sizeof(struct acpi_table_pptt));
+	proc_sz = sizeof(struct acpi_pptt_processor);
+	while ((unsigned long)entry + proc_sz <= table_end) {
+		if (entry->type == ACPI_PPTT_TYPE_PROCESSOR) {
+			struct acpi_pptt_processor *cpu_node;
+
+			cpu_node = (struct acpi_pptt_processor *)entry;
+			if (cpu_node->flags & ACPI_PPTT_ACPI_PROCESSOR_ID_VALID &&
+			    !acpi_pptt_leaf_node(table_hdr, cpu_node) &&
+			    cpu_node->acpi_processor_id == acpi_cpu_id) {
+				acpi_pptt_get_child_cpus(table_hdr, cpu_node, cpus);
+				break;
+			}
+		}
+		entry = ACPI_ADD_PTR(struct acpi_subtable_header, entry,
+				     entry->length);
+	}
+}
+
+/**
+ * find_acpi_cache_level_from_id() - Get the level of the specified cache
+ * @cache_id: The id field of the cache
+ *
+ * Determine the level relative to any CPU for the cache identified by
+ * cache_id. This allows the property to be found even if the CPUs are offline.
+ *
+ * The returned level can be used to group caches that are peers.
+ *
+ * The PPTT table must be rev 3 or later.
+ *
+ * If one CPU's L2 is shared with another CPU as L3, this function will return
+ * an unpredictable value.
+ *
+ * Return: -ENOENT if the PPTT doesn't exist, the revision isn't supported or
+ * the cache cannot be found.
+ * Otherwise returns a value which represents the level of the specified cache.
+ */
+int find_acpi_cache_level_from_id(u32 cache_id)
+{
+	int cpu;
+	struct acpi_table_header *table;
+
+	table = acpi_get_pptt();
+	if (!table)
+		return -ENOENT;
+
+	if (table->revision < 3)
+		return -ENOENT;
+
+	for_each_possible_cpu(cpu) {
+		bool empty;
+		int level = 1;
+		u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu);
+		struct acpi_pptt_cache *cache;
+		struct acpi_pptt_processor *cpu_node;
+
+		cpu_node = acpi_find_processor_node(table, acpi_cpu_id);
+		if (!cpu_node)
+			continue;
+
+		do {
+			int cache_type[] = {CACHE_TYPE_INST, CACHE_TYPE_DATA, CACHE_TYPE_UNIFIED};
+
+			empty = true;
+			for (int i = 0; i < ARRAY_SIZE(cache_type); i++) {
+				struct acpi_pptt_cache_v1_full *cache_v1;
+
+				cache = acpi_find_cache_node(table, acpi_cpu_id, cache_type[i],
+							     level, &cpu_node);
+				if (!cache)
+					continue;
+
+				empty = false;
+
+				cache_v1 = upgrade_pptt_cache(cache);
+				if (cache_v1 && cache_v1->cache_id == cache_id)
+					return level;
+			}
+			level++;
+		} while (!empty);
+	}
+
+	return -ENOENT;
+}
+
+/**
+ * acpi_pptt_get_cpumask_from_cache_id() - Get the cpus associated with the
+ *					   specified cache
+ * @cache_id: The id field of the cache
+ * @cpus: Where to build the cpumask
+ *
+ * Determine which CPUs are below this cache in the PPTT. This allows the property
+ * to be found even if the CPUs are offline.
+ *
+ * The PPTT table must be rev 3 or later,
+ *
+ * Return: -ENOENT if the PPTT doesn't exist, or the cache cannot be found.
+ * Otherwise returns 0 and sets the cpus in the provided cpumask.
+ */
+int acpi_pptt_get_cpumask_from_cache_id(u32 cache_id, cpumask_t *cpus)
+{
+	int cpu;
+	struct acpi_table_header *table;
+
+	cpumask_clear(cpus);
+
+	table = acpi_get_pptt();
+	if (!table)
+		return -ENOENT;
+
+	if (table->revision < 3)
+		return -ENOENT;
+
+	for_each_possible_cpu(cpu) {
+		bool empty;
+		int level = 1;
+		u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu);
+		struct acpi_pptt_cache *cache;
+		struct acpi_pptt_processor *cpu_node;
+
+		cpu_node = acpi_find_processor_node(table, acpi_cpu_id);
+		if (!cpu_node)
+			continue;
+
+		do {
+			int cache_type[] = {CACHE_TYPE_INST, CACHE_TYPE_DATA, CACHE_TYPE_UNIFIED};
+
+			empty = true;
+			for (int i = 0; i < ARRAY_SIZE(cache_type); i++) {
+				struct acpi_pptt_cache_v1_full *cache_v1;
+
+				cache = acpi_find_cache_node(table, acpi_cpu_id, cache_type[i],
+							     level, &cpu_node);
+
+				if (!cache)
+					continue;
+
+				empty = false;
+
+				cache_v1 = upgrade_pptt_cache(cache);
+				if (cache_v1 && cache_v1->cache_id == cache_id)
+					cpumask_set_cpu(cpu, cpus);
+			}
+			level++;
+		} while (!empty);
+	}
+
+	return 0;
+}