diff options
| -rw-r--r-- | drivers/acpi/pptt.c | 84 | ||||
| -rw-r--r-- | include/linux/acpi.h | 3 |
2 files changed, 87 insertions, 0 deletions
diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c index 54676e3d82dd..b8248c0092fe 100644 --- a/drivers/acpi/pptt.c +++ b/drivers/acpi/pptt.c @@ -817,3 +817,87 @@ 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); + } +} diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 5ff5d99f6ead..4752ebd48132 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -1541,6 +1541,7 @@ int find_acpi_cpu_topology(unsigned int cpu, int level); int find_acpi_cpu_topology_cluster(unsigned int cpu); int find_acpi_cpu_topology_package(unsigned int cpu); int find_acpi_cpu_topology_hetero_id(unsigned int cpu); +void acpi_pptt_get_cpus_from_container(u32 acpi_cpu_id, cpumask_t *cpus); #else static inline int acpi_pptt_cpu_is_thread(unsigned int cpu) { @@ -1562,6 +1563,8 @@ static inline int find_acpi_cpu_topology_hetero_id(unsigned int cpu) { return -EINVAL; } +static inline void acpi_pptt_get_cpus_from_container(u32 acpi_cpu_id, + cpumask_t *cpus) { } #endif void acpi_arch_init(void); |