Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:
 "Apart from the core arm64 and perf changes, the Spectre v4 mitigation
  touches the arm KVM code and the ACPI PPTT support touches drivers/
  (acpi and cacheinfo). I should have the maintainers' acks in place.

  Summary:

   - Spectre v4 mitigation (Speculative Store Bypass Disable) support
     for arm64 using SMC firmware call to set a hardware chicken bit

   - ACPI PPTT (Processor Properties Topology Table) parsing support and
     enable the feature for arm64

   - Report signal frame size to user via auxv (AT_MINSIGSTKSZ). The
     primary motivation is Scalable Vector Extensions which requires
     more space on the signal frame than the currently defined
     MINSIGSTKSZ

   - ARM perf patches: allow building arm-cci as module, demote
     dev_warn() to dev_dbg() in arm-ccn event_init(), miscellaneous
     cleanups

   - cmpwait() WFE optimisation to avoid some spurious wakeups

   - L1_CACHE_BYTES reverted back to 64 (for performance reasons that
     have to do with some network allocations) while keeping
     ARCH_DMA_MINALIGN to 128. cache_line_size() returns the actual
     hardware Cache Writeback Granule

   - Turn LSE atomics on by default in Kconfig

   - Kernel fault reporting tidying

   - Some #include and miscellaneous cleanups"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (53 commits)
  arm64: Fix syscall restarting around signal suppressed by tracer
  arm64: topology: Avoid checking numa mask for scheduler MC selection
  ACPI / PPTT: fix build when CONFIG_ACPI_PPTT is not enabled
  arm64: cpu_errata: include required headers
  arm64: KVM: Move VCPU_WORKAROUND_2_FLAG macros to the top of the file
  arm64: signal: Report signal frame size to userspace via auxv
  arm64/sve: Thin out initialisation sanity-checks for sve_max_vl
  arm64: KVM: Add ARCH_WORKAROUND_2 discovery through ARCH_FEATURES_FUNC_ID
  arm64: KVM: Handle guest's ARCH_WORKAROUND_2 requests
  arm64: KVM: Add ARCH_WORKAROUND_2 support for guests
  arm64: KVM: Add HYP per-cpu accessors
  arm64: ssbd: Add prctl interface for per-thread mitigation
  arm64: ssbd: Introduce thread flag to control userspace mitigation
  arm64: ssbd: Restore mitigation status on CPU resume
  arm64: ssbd: Skip apply_ssbd if not using dynamic mitigation
  arm64: ssbd: Add global mitigation state accessor
  arm64: Add 'ssbd' command-line option
  arm64: Add ARCH_WORKAROUND_2 probing
  arm64: Add per-cpu infrastructure to call ARCH_WORKAROUND_2
  arm64: Call ARCH_WORKAROUND_2 on transitions between EL0 and EL1
  ...

4 files changed, 660 insertions, 1 deletions

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 516d7b3..b533eeb 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -547,6 +547,9 @@ config ACPI_CONFIGFS
 
 if ARM64
 source "drivers/acpi/arm64/Kconfig"
+
+config ACPI_PPTT
+	bool
 endif
 
 config TPS68470_PMIC_OPREGION
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 48e2027..6d59aa1 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -88,6 +88,7 @@ obj-$(CONFIG_ACPI_BGRT)		+= bgrt.o
 obj-$(CONFIG_ACPI_CPPC_LIB)	+= cppc_acpi.o
 obj-$(CONFIG_ACPI_SPCR_TABLE)	+= spcr.o
 obj-$(CONFIG_ACPI_DEBUGGER_USER) += acpi_dbg.o
+obj-$(CONFIG_ACPI_PPTT) 	+= pptt.o
 
 # processor has its own "processor." module_param namespace
 processor-y			:= processor_driver.o
diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c
new file mode 100644
index 0000000..e5ea197
--- /dev/null
+++ b/drivers/acpi/pptt.c
@@ -0,0 +1,655 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * pptt.c - parsing of Processor Properties Topology Table (PPTT)
+ *
+ * Copyright (C) 2018, ARM
+ *
+ * This file implements parsing of the Processor Properties Topology Table
+ * which is optionally used to describe the processor and cache topology.
+ * Due to the relative pointers used throughout the table, this doesn't
+ * leverage the existing subtable parsing in the kernel.
+ *
+ * The PPTT structure is an inverted tree, with each node potentially
+ * holding one or two inverted tree data structures describing
+ * the caches available at that level. Each cache structure optionally
+ * contains properties describing the cache at a given level which can be
+ * used to override hardware probed values.
+ */
+#define pr_fmt(fmt) "ACPI PPTT: " fmt
+
+#include <linux/acpi.h>
+#include <linux/cacheinfo.h>
+#include <acpi/processor.h>
+
+static struct acpi_subtable_header *fetch_pptt_subtable(struct acpi_table_header *table_hdr,
+							u32 pptt_ref)
+{
+	struct acpi_subtable_header *entry;
+
+	/* there isn't a subtable at reference 0 */
+	if (pptt_ref < sizeof(struct acpi_subtable_header))
+		return NULL;
+
+	if (pptt_ref + sizeof(struct acpi_subtable_header) > table_hdr->length)
+		return NULL;
+
+	entry = ACPI_ADD_PTR(struct acpi_subtable_header, table_hdr, pptt_ref);
+
+	if (entry->length == 0)
+		return NULL;
+
+	if (pptt_ref + entry->length > table_hdr->length)
+		return NULL;
+
+	return entry;
+}
+
+static struct acpi_pptt_processor *fetch_pptt_node(struct acpi_table_header *table_hdr,
+						   u32 pptt_ref)
+{
+	return (struct acpi_pptt_processor *)fetch_pptt_subtable(table_hdr, pptt_ref);
+}
+
+static struct acpi_pptt_cache *fetch_pptt_cache(struct acpi_table_header *table_hdr,
+						u32 pptt_ref)
+{
+	return (struct acpi_pptt_cache *)fetch_pptt_subtable(table_hdr, pptt_ref);
+}
+
+static struct acpi_subtable_header *acpi_get_pptt_resource(struct acpi_table_header *table_hdr,
+							   struct acpi_pptt_processor *node,
+							   int resource)
+{
+	u32 *ref;
+
+	if (resource >= node->number_of_priv_resources)
+		return NULL;
+
+	ref = ACPI_ADD_PTR(u32, node, sizeof(struct acpi_pptt_processor));
+	ref += resource;
+
+	return fetch_pptt_subtable(table_hdr, *ref);
+}
+
+static inline bool acpi_pptt_match_type(int table_type, int type)
+{
+	return ((table_type & ACPI_PPTT_MASK_CACHE_TYPE) == type ||
+		table_type & ACPI_PPTT_CACHE_TYPE_UNIFIED & type);
+}
+
+/**
+ * acpi_pptt_walk_cache() - Attempt to find the requested acpi_pptt_cache
+ * @table_hdr: Pointer to the head of the PPTT table
+ * @local_level: passed res reflects this cache level
+ * @res: cache resource in the PPTT we want to walk
+ * @found: returns a pointer to the requested level if found
+ * @level: the requested cache level
+ * @type: the requested cache type
+ *
+ * Attempt to find a given cache level, while counting the max number
+ * of cache levels for the cache node.
+ *
+ * Given a pptt resource, verify that it is a cache node, then walk
+ * down each level of caches, counting how many levels are found
+ * as well as checking the cache type (icache, dcache, unified). If a
+ * level & type match, then we set found, and continue the search.
+ * Once the entire cache branch has been walked return its max
+ * depth.
+ *
+ * Return: The cache structure and the level we terminated with.
+ */
+static int acpi_pptt_walk_cache(struct acpi_table_header *table_hdr,
+				int local_level,
+				struct acpi_subtable_header *res,
+				struct acpi_pptt_cache **found,
+				int level, int type)
+{
+	struct acpi_pptt_cache *cache;
+
+	if (res->type != ACPI_PPTT_TYPE_CACHE)
+		return 0;
+
+	cache = (struct acpi_pptt_cache *) res;
+	while (cache) {
+		local_level++;
+
+		if (local_level == level &&
+		    cache->flags & ACPI_PPTT_CACHE_TYPE_VALID &&
+		    acpi_pptt_match_type(cache->attributes, type)) {
+			if (*found != NULL && cache != *found)
+				pr_warn("Found duplicate cache level/type unable to determine uniqueness\n");
+
+			pr_debug("Found cache @ level %d\n", level);
+			*found = cache;
+			/*
+			 * continue looking at this node's resource list
+			 * to verify that we don't find a duplicate
+			 * cache node.
+			 */
+		}
+		cache = fetch_pptt_cache(table_hdr, cache->next_level_of_cache);
+	}
+	return local_level;
+}
+
+static struct acpi_pptt_cache *acpi_find_cache_level(struct acpi_table_header *table_hdr,
+						     struct acpi_pptt_processor *cpu_node,
+						     int *starting_level, int level,
+						     int type)
+{
+	struct acpi_subtable_header *res;
+	int number_of_levels = *starting_level;
+	int resource = 0;
+	struct acpi_pptt_cache *ret = NULL;
+	int local_level;
+
+	/* walk down from processor node */
+	while ((res = acpi_get_pptt_resource(table_hdr, cpu_node, resource))) {
+		resource++;
+
+		local_level = acpi_pptt_walk_cache(table_hdr, *starting_level,
+						   res, &ret, level, type);
+		/*
+		 * we are looking for the max depth. Since its potentially
+		 * possible for a given node to have resources with differing
+		 * depths verify that the depth we have found is the largest.
+		 */
+		if (number_of_levels < local_level)
+			number_of_levels = local_level;
+	}
+	if (number_of_levels > *starting_level)
+		*starting_level = number_of_levels;
+
+	return ret;
+}
+
+/**
+ * acpi_count_levels() - Given a PPTT table, and a cpu node, count the caches
+ * @table_hdr: Pointer to the head of the PPTT table
+ * @cpu_node: processor node we wish to count caches for
+ *
+ * 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
+ * caches that exist across packages). Count the number of cache levels that
+ * exist at each level on the way up.
+ *
+ * Return: Total number of levels found.
+ */
+static int acpi_count_levels(struct acpi_table_header *table_hdr,
+			     struct acpi_pptt_processor *cpu_node)
+{
+	int total_levels = 0;
+
+	do {
+		acpi_find_cache_level(table_hdr, cpu_node, &total_levels, 0, 0);
+		cpu_node = fetch_pptt_node(table_hdr, cpu_node->parent);
+	} while (cpu_node);
+
+	return total_levels;
+}
+
+/**
+ * acpi_pptt_leaf_node() - Given a processor node, determine if its a leaf
+ * @table_hdr: Pointer to the head of the PPTT table
+ * @node: passed node is checked to see if its a leaf
+ *
+ * Determine if the *node parameter is a leaf node by iterating the
+ * PPTT table, looking for nodes which reference it.
+ *
+ * Return: 0 if we find a node referencing the passed node (or table error),
+ * or 1 if we don't.
+ */
+static int acpi_pptt_leaf_node(struct acpi_table_header *table_hdr,
+			       struct acpi_pptt_processor *node)
+{
+	struct acpi_subtable_header *entry;
+	unsigned long table_end;
+	u32 node_entry;
+	struct acpi_pptt_processor *cpu_node;
+	u32 proc_sz;
+
+	table_end = (unsigned long)table_hdr + table_hdr->length;
+	node_entry = ACPI_PTR_DIFF(node, table_hdr);
+	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) {
+		cpu_node = (struct acpi_pptt_processor *)entry;
+		if (entry->type == ACPI_PPTT_TYPE_PROCESSOR &&
+		    cpu_node->parent == node_entry)
+			return 0;
+		if (entry->length == 0)
+			return 0;
+		entry = ACPI_ADD_PTR(struct acpi_subtable_header, entry,
+				     entry->length);
+
+	}
+	return 1;
+}
+
+/**
+ * acpi_find_processor_node() - Given a PPTT table find the requested processor
+ * @table_hdr:  Pointer to the head of the PPTT table
+ * @acpi_cpu_id: cpu we are searching for
+ *
+ * Find the subtable entry describing the provided processor.
+ * This is done by iterating the PPTT table looking for processor nodes
+ * which have an acpi_processor_id that matches the acpi_cpu_id parameter
+ * passed into the function. If we find a node that matches this criteria
+ * we verify that its a leaf node in the topology rather than depending
+ * on the valid flag, which doesn't need to be set for leaf nodes.
+ *
+ * Return: NULL, or the processors acpi_pptt_processor*
+ */
+static struct acpi_pptt_processor *acpi_find_processor_node(struct acpi_table_header *table_hdr,
+							    u32 acpi_cpu_id)
+{
+	struct acpi_subtable_header *entry;
+	unsigned long table_end;
+	struct acpi_pptt_processor *cpu_node;
+	u32 proc_sz;
+
+	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 *);
+
+	/* find the processor structure associated with this cpuid */
+	while ((unsigned long)entry + proc_sz < table_end) {
+		cpu_node = (struct acpi_pptt_processor *)entry;
+
+		if (entry->length == 0) {
+			pr_warn("Invalid zero length subtable\n");
+			break;
+		}
+		if (entry->type == ACPI_PPTT_TYPE_PROCESSOR &&
+		    acpi_cpu_id == cpu_node->acpi_processor_id &&
+		     acpi_pptt_leaf_node(table_hdr, cpu_node)) {
+			return (struct acpi_pptt_processor *)entry;
+		}
+
+		entry = ACPI_ADD_PTR(struct acpi_subtable_header, entry,
+				     entry->length);
+	}
+
+	return NULL;
+}
+
+static int acpi_find_cache_levels(struct acpi_table_header *table_hdr,
+				  u32 acpi_cpu_id)
+{
+	int number_of_levels = 0;
+	struct acpi_pptt_processor *cpu;
+
+	cpu = acpi_find_processor_node(table_hdr, acpi_cpu_id);
+	if (cpu)
+		number_of_levels = acpi_count_levels(table_hdr, cpu);
+
+	return number_of_levels;
+}
+
+static u8 acpi_cache_type(enum cache_type type)
+{
+	switch (type) {
+	case CACHE_TYPE_DATA:
+		pr_debug("Looking for data cache\n");
+		return ACPI_PPTT_CACHE_TYPE_DATA;
+	case CACHE_TYPE_INST:
+		pr_debug("Looking for instruction cache\n");
+		return ACPI_PPTT_CACHE_TYPE_INSTR;
+	default:
+	case CACHE_TYPE_UNIFIED:
+		pr_debug("Looking for unified cache\n");
+		/*
+		 * It is important that ACPI_PPTT_CACHE_TYPE_UNIFIED
+		 * contains the bit pattern that will match both
+		 * ACPI unified bit patterns because we use it later
+		 * to match both cases.
+		 */
+		return ACPI_PPTT_CACHE_TYPE_UNIFIED;
+	}
+}
+
+static struct acpi_pptt_cache *acpi_find_cache_node(struct acpi_table_header *table_hdr,
+						    u32 acpi_cpu_id,
+						    enum cache_type type,
+						    unsigned int level,
+						    struct acpi_pptt_processor **node)
+{
+	int total_levels = 0;
+	struct acpi_pptt_cache *found = NULL;
+	struct acpi_pptt_processor *cpu_node;
+	u8 acpi_type = acpi_cache_type(type);
+
+	pr_debug("Looking for CPU %d's level %d cache type %d\n",
+		 acpi_cpu_id, level, acpi_type);
+
+	cpu_node = acpi_find_processor_node(table_hdr, acpi_cpu_id);
+
+	while (cpu_node && !found) {
+		found = acpi_find_cache_level(table_hdr, cpu_node,
+					      &total_levels, level, acpi_type);
+		*node = cpu_node;
+		cpu_node = fetch_pptt_node(table_hdr, cpu_node->parent);
+	}
+
+	return found;
+}
+
+/* total number of attributes checked by the properties code */
+#define PPTT_CHECKED_ATTRIBUTES 4
+
+/**
+ * update_cache_properties() - Update cacheinfo for the given processor
+ * @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
+ *
+ * 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
+ * set fields that we determine are VALID.
+ *
+ * Return: nothing. Side effect of updating the global cacheinfo
+ */
+static void update_cache_properties(struct cacheinfo *this_leaf,
+				    struct acpi_pptt_cache *found_cache,
+				    struct acpi_pptt_processor *cpu_node)
+{
+	int valid_flags = 0;
+
+	this_leaf->fw_token = cpu_node;
+	if (found_cache->flags & ACPI_PPTT_SIZE_PROPERTY_VALID) {
+		this_leaf->size = found_cache->size;
+		valid_flags++;
+	}
+	if (found_cache->flags & ACPI_PPTT_LINE_SIZE_VALID) {
+		this_leaf->coherency_line_size = found_cache->line_size;
+		valid_flags++;
+	}
+	if (found_cache->flags & ACPI_PPTT_NUMBER_OF_SETS_VALID) {
+		this_leaf->number_of_sets = found_cache->number_of_sets;
+		valid_flags++;
+	}
+	if (found_cache->flags & ACPI_PPTT_ASSOCIATIVITY_VALID) {
+		this_leaf->ways_of_associativity = found_cache->associativity;
+		valid_flags++;
+	}
+	if (found_cache->flags & ACPI_PPTT_WRITE_POLICY_VALID) {
+		switch (found_cache->attributes & ACPI_PPTT_MASK_WRITE_POLICY) {
+		case ACPI_PPTT_CACHE_POLICY_WT:
+			this_leaf->attributes = CACHE_WRITE_THROUGH;
+			break;
+		case ACPI_PPTT_CACHE_POLICY_WB:
+			this_leaf->attributes = CACHE_WRITE_BACK;
+			break;
+		}
+	}
+	if (found_cache->flags & ACPI_PPTT_ALLOCATION_TYPE_VALID) {
+		switch (found_cache->attributes & ACPI_PPTT_MASK_ALLOCATION_TYPE) {
+		case ACPI_PPTT_CACHE_READ_ALLOCATE:
+			this_leaf->attributes |= CACHE_READ_ALLOCATE;
+			break;
+		case ACPI_PPTT_CACHE_WRITE_ALLOCATE:
+			this_leaf->attributes |= CACHE_WRITE_ALLOCATE;
+			break;
+		case ACPI_PPTT_CACHE_RW_ALLOCATE:
+		case ACPI_PPTT_CACHE_RW_ALLOCATE_ALT:
+			this_leaf->attributes |=
+				CACHE_READ_ALLOCATE | CACHE_WRITE_ALLOCATE;
+			break;
+		}
+	}
+	/*
+	 * If the above flags are valid, and the cache type is NOCACHE
+	 * update the cache type as well.
+	 */
+	if (this_leaf->type == CACHE_TYPE_NOCACHE &&
+	    valid_flags == PPTT_CHECKED_ATTRIBUTES)
+		this_leaf->type = CACHE_TYPE_UNIFIED;
+}
+
+static void cache_setup_acpi_cpu(struct acpi_table_header *table,
+				 unsigned int cpu)
+{
+	struct acpi_pptt_cache *found_cache;
+	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+	u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu);
+	struct cacheinfo *this_leaf;
+	unsigned int index = 0;
+	struct acpi_pptt_processor *cpu_node = NULL;
+
+	while (index < get_cpu_cacheinfo(cpu)->num_leaves) {
+		this_leaf = this_cpu_ci->info_list + index;
+		found_cache = acpi_find_cache_node(table, acpi_cpu_id,
+						   this_leaf->type,
+						   this_leaf->level,
+						   &cpu_node);
+		pr_debug("found = %p %p\n", found_cache, cpu_node);
+		if (found_cache)
+			update_cache_properties(this_leaf,
+						found_cache,
+						cpu_node);
+
+		index++;
+	}
+}
+
+/* Passing level values greater than this will result in search termination */
+#define PPTT_ABORT_PACKAGE 0xFF
+
+static struct acpi_pptt_processor *acpi_find_processor_package_id(struct acpi_table_header *table_hdr,
+								  struct acpi_pptt_processor *cpu,
+								  int level, int flag)
+{
+	struct acpi_pptt_processor *prev_node;
+
+	while (cpu && level) {
+		if (cpu->flags & flag)
+			break;
+		pr_debug("level %d\n", level);
+		prev_node = fetch_pptt_node(table_hdr, cpu->parent);
+		if (prev_node == NULL)
+			break;
+		cpu = prev_node;
+		level--;
+	}
+	return cpu;
+}
+
+/**
+ * topology_get_acpi_cpu_tag() - Find a unique topology value for a feature
+ * @table: Pointer to the head of the PPTT table
+ * @cpu: Kernel logical cpu number
+ * @level: A level that terminates the search
+ * @flag: A flag which terminates the search
+ *
+ * Get a unique value given a cpu, and a topology level, that can be
+ * matched to determine which cpus share common topological features
+ * at that level.
+ *
+ * Return: Unique value, or -ENOENT if unable to locate cpu
+ */
+static int topology_get_acpi_cpu_tag(struct acpi_table_header *table,
+				     unsigned int cpu, int level, int flag)
+{
+	struct acpi_pptt_processor *cpu_node;
+	u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu);
+
+	cpu_node = acpi_find_processor_node(table, acpi_cpu_id);
+	if (cpu_node) {
+		cpu_node = acpi_find_processor_package_id(table, cpu_node,
+							  level, flag);
+		/* Only the first level has a guaranteed id */
+		if (level == 0)
+			return cpu_node->acpi_processor_id;
+		return ACPI_PTR_DIFF(cpu_node, table);
+	}
+	pr_warn_once("PPTT table found, but unable to locate core %d (%d)\n",
+		    cpu, acpi_cpu_id);
+	return -ENOENT;
+}
+
+static int find_acpi_cpu_topology_tag(unsigned int cpu, int level, int flag)
+{
+	struct acpi_table_header *table;
+	acpi_status status;
+	int retval;
+
+	status = acpi_get_table(ACPI_SIG_PPTT, 0, &table);
+	if (ACPI_FAILURE(status)) {
+		pr_warn_once("No PPTT table found, cpu topology may be inaccurate\n");
+		return -ENOENT;
+	}
+	retval = topology_get_acpi_cpu_tag(table, cpu, level, flag);
+	pr_debug("Topology Setup ACPI cpu %d, level %d ret = %d\n",
+		 cpu, level, retval);
+	acpi_put_table(table);
+
+	return retval;
+}
+
+/**
+ * acpi_find_last_cache_level() - Determines the number of cache levels for a PE
+ * @cpu: Kernel logical cpu number
+ *
+ * Given a logical cpu number, returns the number of levels of cache represented
+ * in the PPTT. Errors caused by lack of a PPTT table, or otherwise, return 0
+ * indicating we didn't find any cache levels.
+ *
+ * Return: Cache levels visible to this core.
+ */
+int acpi_find_last_cache_level(unsigned int cpu)
+{
+	u32 acpi_cpu_id;
+	struct acpi_table_header *table;
+	int number_of_levels = 0;
+	acpi_status status;
+
+	pr_debug("Cache Setup find last level cpu=%d\n", cpu);
+
+	acpi_cpu_id = get_acpi_id_for_cpu(cpu);
+	status = acpi_get_table(ACPI_SIG_PPTT, 0, &table);
+	if (ACPI_FAILURE(status)) {
+		pr_warn_once("No PPTT table found, cache topology may be inaccurate\n");
+	} else {
+		number_of_levels = acpi_find_cache_levels(table, acpi_cpu_id);
+		acpi_put_table(table);
+	}
+	pr_debug("Cache Setup find last level level=%d\n", number_of_levels);
+
+	return number_of_levels;
+}
+
+/**
+ * cache_setup_acpi() - Override CPU cache topology with data from the PPTT
+ * @cpu: Kernel logical cpu number
+ *
+ * Updates the global cache info provided by cpu_get_cacheinfo()
+ * when there are valid properties in the acpi_pptt_cache nodes. A
+ * successful parse may not result in any updates if none of the
+ * cache levels have any valid flags set.  Futher, a unique value is
+ * associated with each known CPU cache entry. This unique value
+ * can be used to determine whether caches are shared between cpus.
+ *
+ * Return: -ENOENT on failure to find table, or 0 on success
+ */
+int cache_setup_acpi(unsigned int cpu)
+{
+	struct acpi_table_header *table;
+	acpi_status status;
+
+	pr_debug("Cache Setup ACPI cpu %d\n", cpu);
+
+	status = acpi_get_table(ACPI_SIG_PPTT, 0, &table);
+	if (ACPI_FAILURE(status)) {
+		pr_warn_once("No PPTT table found, cache topology may be inaccurate\n");
+		return -ENOENT;
+	}
+
+	cache_setup_acpi_cpu(table, cpu);
+	acpi_put_table(table);
+
+	return status;
+}
+
+/**
+ * find_acpi_cpu_topology() - Determine a unique topology value for a given cpu
+ * @cpu: Kernel logical cpu number
+ * @level: The topological level for which we would like a unique ID
+ *
+ * Determine a topology unique ID for each thread/core/cluster/mc_grouping
+ * /socket/etc. This ID can then be used to group peers, which will have
+ * matching ids.
+ *
+ * The search terminates when either the requested level is found or
+ * we reach a root node. Levels beyond the termination point will return the
+ * same unique ID. The unique id for level 0 is the acpi processor id. All
+ * other levels beyond this use a generated value to uniquely identify
+ * a topological feature.
+ *
+ * Return: -ENOENT if the PPTT doesn't exist, or the cpu cannot be found.
+ * Otherwise returns a value which represents a unique topological feature.
+ */
+int find_acpi_cpu_topology(unsigned int cpu, int level)
+{
+	return find_acpi_cpu_topology_tag(cpu, level, 0);
+}
+
+/**
+ * find_acpi_cpu_cache_topology() - Determine a unique cache topology value
+ * @cpu: Kernel logical cpu number
+ * @level: The cache level for which we would like a unique ID
+ *
+ * Determine a unique ID for each unified cache in the system
+ *
+ * Return: -ENOENT if the PPTT doesn't exist, or the cpu cannot be found.
+ * Otherwise returns a value which represents a unique topological feature.
+ */
+int find_acpi_cpu_cache_topology(unsigned int cpu, int level)
+{
+	struct acpi_table_header *table;
+	struct acpi_pptt_cache *found_cache;
+	acpi_status status;
+	u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu);
+	struct acpi_pptt_processor *cpu_node = NULL;
+	int ret = -1;
+
+	status = acpi_get_table(ACPI_SIG_PPTT, 0, &table);
+	if (ACPI_FAILURE(status)) {
+		pr_warn_once("No PPTT table found, topology may be inaccurate\n");
+		return -ENOENT;
+	}
+
+	found_cache = acpi_find_cache_node(table, acpi_cpu_id,
+					   CACHE_TYPE_UNIFIED,
+					   level,
+					   &cpu_node);
+	if (found_cache)
+		ret = ACPI_PTR_DIFF(cpu_node, table);
+
+	acpi_put_table(table);
+
+	return ret;
+}
+
+
+/**
+ * find_acpi_cpu_topology_package() - Determine a unique cpu package value
+ * @cpu: Kernel logical cpu number
+ *
+ * Determine a topology unique package ID for the given cpu.
+ * This ID can then be used to group peers, which will have matching ids.
+ *
+ * The search terminates when either a level is found with the PHYSICAL_PACKAGE
+ * flag set or we reach a root node.
+ *
+ * Return: -ENOENT if the PPTT doesn't exist, or the cpu cannot be found.
+ * Otherwise returns a value which represents the package for this cpu.
+ */
+int find_acpi_cpu_topology_package(unsigned int cpu)
+{
+	return find_acpi_cpu_topology_tag(cpu, PPTT_ABORT_PACKAGE,
+					  ACPI_PPTT_PHYSICAL_PACKAGE);
+}
diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c
index 4a3410a..a3d012b 100644
--- a/drivers/acpi/tables.c
+++ b/drivers/acpi/tables.c
@@ -462,7 +462,7 @@ static const char * const table_sigs[] = {
 	ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT, ACPI_SIG_WDDT,
 	ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT, ACPI_SIG_PSDT,
 	ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT, ACPI_SIG_IORT,
-	ACPI_SIG_NFIT, ACPI_SIG_HMAT, NULL };
+	ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT, NULL };
 
 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)