|  | // SPDX-License-Identifier: GPL-2.0-or-later | 
|  | /* | 
|  | *  acpi_numa.c - ACPI NUMA support | 
|  | * | 
|  | *  Copyright (C) 2002 Takayoshi Kochi <t-kochi@bq.jp.nec.com> | 
|  | */ | 
|  |  | 
|  | #define pr_fmt(fmt) "ACPI: " fmt | 
|  |  | 
|  | #include <linux/module.h> | 
|  | #include <linux/init.h> | 
|  | #include <linux/kernel.h> | 
|  | #include <linux/types.h> | 
|  | #include <linux/errno.h> | 
|  | #include <linux/acpi.h> | 
|  | #include <linux/memblock.h> | 
|  | #include <linux/numa.h> | 
|  | #include <linux/nodemask.h> | 
|  | #include <linux/topology.h> | 
|  |  | 
|  | static nodemask_t nodes_found_map = NODE_MASK_NONE; | 
|  |  | 
|  | /* maps to convert between proximity domain and logical node ID */ | 
|  | static int pxm_to_node_map[MAX_PXM_DOMAINS] | 
|  | = { [0 ... MAX_PXM_DOMAINS - 1] = NUMA_NO_NODE }; | 
|  | static int node_to_pxm_map[MAX_NUMNODES] | 
|  | = { [0 ... MAX_NUMNODES - 1] = PXM_INVAL }; | 
|  |  | 
|  | unsigned char acpi_srat_revision __initdata; | 
|  | static int acpi_numa __initdata; | 
|  |  | 
|  | void __init disable_srat(void) | 
|  | { | 
|  | acpi_numa = -1; | 
|  | } | 
|  |  | 
|  | int pxm_to_node(int pxm) | 
|  | { | 
|  | if (pxm < 0 || pxm >= MAX_PXM_DOMAINS || numa_off) | 
|  | return NUMA_NO_NODE; | 
|  | return pxm_to_node_map[pxm]; | 
|  | } | 
|  | EXPORT_SYMBOL(pxm_to_node); | 
|  |  | 
|  | int node_to_pxm(int node) | 
|  | { | 
|  | if (node < 0) | 
|  | return PXM_INVAL; | 
|  | return node_to_pxm_map[node]; | 
|  | } | 
|  |  | 
|  | static void __acpi_map_pxm_to_node(int pxm, int node) | 
|  | { | 
|  | if (pxm_to_node_map[pxm] == NUMA_NO_NODE || node < pxm_to_node_map[pxm]) | 
|  | pxm_to_node_map[pxm] = node; | 
|  | if (node_to_pxm_map[node] == PXM_INVAL || pxm < node_to_pxm_map[node]) | 
|  | node_to_pxm_map[node] = pxm; | 
|  | } | 
|  |  | 
|  | int acpi_map_pxm_to_node(int pxm) | 
|  | { | 
|  | int node; | 
|  |  | 
|  | if (pxm < 0 || pxm >= MAX_PXM_DOMAINS || numa_off) | 
|  | return NUMA_NO_NODE; | 
|  |  | 
|  | node = pxm_to_node_map[pxm]; | 
|  |  | 
|  | if (node == NUMA_NO_NODE) { | 
|  | node = first_unset_node(nodes_found_map); | 
|  | if (node >= MAX_NUMNODES) | 
|  | return NUMA_NO_NODE; | 
|  | __acpi_map_pxm_to_node(pxm, node); | 
|  | node_set(node, nodes_found_map); | 
|  | } | 
|  |  | 
|  | return node; | 
|  | } | 
|  | EXPORT_SYMBOL(acpi_map_pxm_to_node); | 
|  |  | 
|  | static void __init | 
|  | acpi_table_print_srat_entry(struct acpi_subtable_header *header) | 
|  | { | 
|  | switch (header->type) { | 
|  | case ACPI_SRAT_TYPE_CPU_AFFINITY: | 
|  | { | 
|  | struct acpi_srat_cpu_affinity *p = | 
|  | (struct acpi_srat_cpu_affinity *)header; | 
|  | pr_debug("SRAT Processor (id[0x%02x] eid[0x%02x]) in proximity domain %d %s\n", | 
|  | p->apic_id, p->local_sapic_eid, | 
|  | p->proximity_domain_lo, | 
|  | (p->flags & ACPI_SRAT_CPU_ENABLED) ? | 
|  | "enabled" : "disabled"); | 
|  | } | 
|  | break; | 
|  |  | 
|  | case ACPI_SRAT_TYPE_MEMORY_AFFINITY: | 
|  | { | 
|  | struct acpi_srat_mem_affinity *p = | 
|  | (struct acpi_srat_mem_affinity *)header; | 
|  | pr_debug("SRAT Memory (0x%llx length 0x%llx) in proximity domain %d %s%s%s\n", | 
|  | (unsigned long long)p->base_address, | 
|  | (unsigned long long)p->length, | 
|  | p->proximity_domain, | 
|  | (p->flags & ACPI_SRAT_MEM_ENABLED) ? | 
|  | "enabled" : "disabled", | 
|  | (p->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) ? | 
|  | " hot-pluggable" : "", | 
|  | (p->flags & ACPI_SRAT_MEM_NON_VOLATILE) ? | 
|  | " non-volatile" : ""); | 
|  | } | 
|  | break; | 
|  |  | 
|  | case ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY: | 
|  | { | 
|  | struct acpi_srat_x2apic_cpu_affinity *p = | 
|  | (struct acpi_srat_x2apic_cpu_affinity *)header; | 
|  | pr_debug("SRAT Processor (x2apicid[0x%08x]) in proximity domain %d %s\n", | 
|  | p->apic_id, | 
|  | p->proximity_domain, | 
|  | (p->flags & ACPI_SRAT_CPU_ENABLED) ? | 
|  | "enabled" : "disabled"); | 
|  | } | 
|  | break; | 
|  |  | 
|  | case ACPI_SRAT_TYPE_GICC_AFFINITY: | 
|  | { | 
|  | struct acpi_srat_gicc_affinity *p = | 
|  | (struct acpi_srat_gicc_affinity *)header; | 
|  | pr_debug("SRAT Processor (acpi id[0x%04x]) in proximity domain %d %s\n", | 
|  | p->acpi_processor_uid, | 
|  | p->proximity_domain, | 
|  | (p->flags & ACPI_SRAT_GICC_ENABLED) ? | 
|  | "enabled" : "disabled"); | 
|  | } | 
|  | break; | 
|  |  | 
|  | case ACPI_SRAT_TYPE_GENERIC_AFFINITY: | 
|  | { | 
|  | struct acpi_srat_generic_affinity *p = | 
|  | (struct acpi_srat_generic_affinity *)header; | 
|  |  | 
|  | if (p->device_handle_type == 0) { | 
|  | /* | 
|  | * For pci devices this may be the only place they | 
|  | * are assigned a proximity domain | 
|  | */ | 
|  | pr_debug("SRAT Generic Initiator(Seg:%u BDF:%u) in proximity domain %d %s\n", | 
|  | *(u16 *)(&p->device_handle[0]), | 
|  | *(u16 *)(&p->device_handle[2]), | 
|  | p->proximity_domain, | 
|  | (p->flags & ACPI_SRAT_GENERIC_AFFINITY_ENABLED) ? | 
|  | "enabled" : "disabled"); | 
|  | } else { | 
|  | /* | 
|  | * In this case we can rely on the device having a | 
|  | * proximity domain reference | 
|  | */ | 
|  | pr_debug("SRAT Generic Initiator(HID=%.8s UID=%.4s) in proximity domain %d %s\n", | 
|  | (char *)(&p->device_handle[0]), | 
|  | (char *)(&p->device_handle[8]), | 
|  | p->proximity_domain, | 
|  | (p->flags & ACPI_SRAT_GENERIC_AFFINITY_ENABLED) ? | 
|  | "enabled" : "disabled"); | 
|  | } | 
|  | } | 
|  | break; | 
|  | default: | 
|  | pr_warn("Found unsupported SRAT entry (type = 0x%x)\n", | 
|  | header->type); | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | /* | 
|  | * A lot of BIOS fill in 10 (= no distance) everywhere. This messes | 
|  | * up the NUMA heuristics which wants the local node to have a smaller | 
|  | * distance than the others. | 
|  | * Do some quick checks here and only use the SLIT if it passes. | 
|  | */ | 
|  | static int __init slit_valid(struct acpi_table_slit *slit) | 
|  | { | 
|  | int i, j; | 
|  | int d = slit->locality_count; | 
|  | for (i = 0; i < d; i++) { | 
|  | for (j = 0; j < d; j++) { | 
|  | u8 val = slit->entry[d*i + j]; | 
|  | if (i == j) { | 
|  | if (val != LOCAL_DISTANCE) | 
|  | return 0; | 
|  | } else if (val <= LOCAL_DISTANCE) | 
|  | return 0; | 
|  | } | 
|  | } | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | void __init bad_srat(void) | 
|  | { | 
|  | pr_err("SRAT: SRAT not used.\n"); | 
|  | disable_srat(); | 
|  | } | 
|  |  | 
|  | int __init srat_disabled(void) | 
|  | { | 
|  | return acpi_numa < 0; | 
|  | } | 
|  |  | 
|  | #if defined(CONFIG_X86) || defined(CONFIG_ARM64) || defined(CONFIG_LOONGARCH) | 
|  | /* | 
|  | * Callback for SLIT parsing.  pxm_to_node() returns NUMA_NO_NODE for | 
|  | * I/O localities since SRAT does not list them.  I/O localities are | 
|  | * not supported at this point. | 
|  | */ | 
|  | void __init acpi_numa_slit_init(struct acpi_table_slit *slit) | 
|  | { | 
|  | int i, j; | 
|  |  | 
|  | for (i = 0; i < slit->locality_count; i++) { | 
|  | const int from_node = pxm_to_node(i); | 
|  |  | 
|  | if (from_node == NUMA_NO_NODE) | 
|  | continue; | 
|  |  | 
|  | for (j = 0; j < slit->locality_count; j++) { | 
|  | const int to_node = pxm_to_node(j); | 
|  |  | 
|  | if (to_node == NUMA_NO_NODE) | 
|  | continue; | 
|  |  | 
|  | numa_set_distance(from_node, to_node, | 
|  | slit->entry[slit->locality_count * i + j]); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Default callback for parsing of the Proximity Domain <-> Memory | 
|  | * Area mappings | 
|  | */ | 
|  | int __init | 
|  | acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma) | 
|  | { | 
|  | u64 start, end; | 
|  | u32 hotpluggable; | 
|  | int node, pxm; | 
|  |  | 
|  | if (srat_disabled()) | 
|  | goto out_err; | 
|  | if (ma->header.length < sizeof(struct acpi_srat_mem_affinity)) { | 
|  | pr_err("SRAT: Unexpected header length: %d\n", | 
|  | ma->header.length); | 
|  | goto out_err_bad_srat; | 
|  | } | 
|  | if ((ma->flags & ACPI_SRAT_MEM_ENABLED) == 0) | 
|  | goto out_err; | 
|  | hotpluggable = IS_ENABLED(CONFIG_MEMORY_HOTPLUG) && | 
|  | (ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE); | 
|  |  | 
|  | start = ma->base_address; | 
|  | end = start + ma->length; | 
|  | pxm = ma->proximity_domain; | 
|  | if (acpi_srat_revision <= 1) | 
|  | pxm &= 0xff; | 
|  |  | 
|  | node = acpi_map_pxm_to_node(pxm); | 
|  | if (node == NUMA_NO_NODE) { | 
|  | pr_err("SRAT: Too many proximity domains.\n"); | 
|  | goto out_err_bad_srat; | 
|  | } | 
|  |  | 
|  | if (numa_add_memblk(node, start, end) < 0) { | 
|  | pr_err("SRAT: Failed to add memblk to node %u [mem %#010Lx-%#010Lx]\n", | 
|  | node, (unsigned long long) start, | 
|  | (unsigned long long) end - 1); | 
|  | goto out_err_bad_srat; | 
|  | } | 
|  |  | 
|  | node_set(node, numa_nodes_parsed); | 
|  |  | 
|  | pr_info("SRAT: Node %u PXM %u [mem %#010Lx-%#010Lx]%s%s\n", | 
|  | node, pxm, | 
|  | (unsigned long long) start, (unsigned long long) end - 1, | 
|  | hotpluggable ? " hotplug" : "", | 
|  | ma->flags & ACPI_SRAT_MEM_NON_VOLATILE ? " non-volatile" : ""); | 
|  |  | 
|  | /* Mark hotplug range in memblock. */ | 
|  | if (hotpluggable && memblock_mark_hotplug(start, ma->length)) | 
|  | pr_warn("SRAT: Failed to mark hotplug range [mem %#010Lx-%#010Lx] in memblock\n", | 
|  | (unsigned long long)start, (unsigned long long)end - 1); | 
|  |  | 
|  | max_possible_pfn = max(max_possible_pfn, PFN_UP(end - 1)); | 
|  |  | 
|  | return 0; | 
|  | out_err_bad_srat: | 
|  | bad_srat(); | 
|  | out_err: | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | static int __init acpi_parse_cfmws(union acpi_subtable_headers *header, | 
|  | void *arg, const unsigned long table_end) | 
|  | { | 
|  | struct acpi_cedt_cfmws *cfmws; | 
|  | int *fake_pxm = arg; | 
|  | u64 start, end; | 
|  | int node; | 
|  |  | 
|  | cfmws = (struct acpi_cedt_cfmws *)header; | 
|  | start = cfmws->base_hpa; | 
|  | end = cfmws->base_hpa + cfmws->window_size; | 
|  |  | 
|  | /* | 
|  | * The SRAT may have already described NUMA details for all, | 
|  | * or a portion of, this CFMWS HPA range. Extend the memblks | 
|  | * found for any portion of the window to cover the entire | 
|  | * window. | 
|  | */ | 
|  | if (!numa_fill_memblks(start, end)) | 
|  | return 0; | 
|  |  | 
|  | /* No SRAT description. Create a new node. */ | 
|  | node = acpi_map_pxm_to_node(*fake_pxm); | 
|  |  | 
|  | if (node == NUMA_NO_NODE) { | 
|  | pr_err("ACPI NUMA: Too many proximity domains while processing CFMWS.\n"); | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | if (numa_add_memblk(node, start, end) < 0) { | 
|  | /* CXL driver must handle the NUMA_NO_NODE case */ | 
|  | pr_warn("ACPI NUMA: Failed to add memblk for CFMWS node %d [mem %#llx-%#llx]\n", | 
|  | node, start, end); | 
|  | } | 
|  | node_set(node, numa_nodes_parsed); | 
|  |  | 
|  | /* Set the next available fake_pxm value */ | 
|  | (*fake_pxm)++; | 
|  | return 0; | 
|  | } | 
|  | #else | 
|  | static int __init acpi_parse_cfmws(union acpi_subtable_headers *header, | 
|  | void *arg, const unsigned long table_end) | 
|  | { | 
|  | return 0; | 
|  | } | 
|  | #endif /* defined(CONFIG_X86) || defined (CONFIG_ARM64) */ | 
|  |  | 
|  | static int __init acpi_parse_slit(struct acpi_table_header *table) | 
|  | { | 
|  | struct acpi_table_slit *slit = (struct acpi_table_slit *)table; | 
|  |  | 
|  | if (!slit_valid(slit)) { | 
|  | pr_info("SLIT table looks invalid. Not used.\n"); | 
|  | return -EINVAL; | 
|  | } | 
|  | acpi_numa_slit_init(slit); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | void __init __weak | 
|  | acpi_numa_x2apic_affinity_init(struct acpi_srat_x2apic_cpu_affinity *pa) | 
|  | { | 
|  | pr_warn("Found unsupported x2apic [0x%08x] SRAT entry\n", pa->apic_id); | 
|  | } | 
|  |  | 
|  | static int __init | 
|  | acpi_parse_x2apic_affinity(union acpi_subtable_headers *header, | 
|  | const unsigned long end) | 
|  | { | 
|  | struct acpi_srat_x2apic_cpu_affinity *processor_affinity; | 
|  |  | 
|  | processor_affinity = (struct acpi_srat_x2apic_cpu_affinity *)header; | 
|  |  | 
|  | acpi_table_print_srat_entry(&header->common); | 
|  |  | 
|  | /* let architecture-dependent part to do it */ | 
|  | acpi_numa_x2apic_affinity_init(processor_affinity); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int __init | 
|  | acpi_parse_processor_affinity(union acpi_subtable_headers *header, | 
|  | const unsigned long end) | 
|  | { | 
|  | struct acpi_srat_cpu_affinity *processor_affinity; | 
|  |  | 
|  | processor_affinity = (struct acpi_srat_cpu_affinity *)header; | 
|  |  | 
|  | acpi_table_print_srat_entry(&header->common); | 
|  |  | 
|  | /* let architecture-dependent part to do it */ | 
|  | acpi_numa_processor_affinity_init(processor_affinity); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int __init | 
|  | acpi_parse_gicc_affinity(union acpi_subtable_headers *header, | 
|  | const unsigned long end) | 
|  | { | 
|  | struct acpi_srat_gicc_affinity *processor_affinity; | 
|  |  | 
|  | processor_affinity = (struct acpi_srat_gicc_affinity *)header; | 
|  |  | 
|  | acpi_table_print_srat_entry(&header->common); | 
|  |  | 
|  | /* let architecture-dependent part to do it */ | 
|  | acpi_numa_gicc_affinity_init(processor_affinity); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | #if defined(CONFIG_X86) || defined(CONFIG_ARM64) | 
|  | static int __init | 
|  | acpi_parse_gi_affinity(union acpi_subtable_headers *header, | 
|  | const unsigned long end) | 
|  | { | 
|  | struct acpi_srat_generic_affinity *gi_affinity; | 
|  | int node; | 
|  |  | 
|  | gi_affinity = (struct acpi_srat_generic_affinity *)header; | 
|  | if (!gi_affinity) | 
|  | return -EINVAL; | 
|  | acpi_table_print_srat_entry(&header->common); | 
|  |  | 
|  | if (!(gi_affinity->flags & ACPI_SRAT_GENERIC_AFFINITY_ENABLED)) | 
|  | return -EINVAL; | 
|  |  | 
|  | node = acpi_map_pxm_to_node(gi_affinity->proximity_domain); | 
|  | if (node == NUMA_NO_NODE) { | 
|  | pr_err("SRAT: Too many proximity domains.\n"); | 
|  | return -EINVAL; | 
|  | } | 
|  | node_set(node, numa_nodes_parsed); | 
|  | node_set_state(node, N_GENERIC_INITIATOR); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  | #else | 
|  | static int __init | 
|  | acpi_parse_gi_affinity(union acpi_subtable_headers *header, | 
|  | const unsigned long end) | 
|  | { | 
|  | return 0; | 
|  | } | 
|  | #endif /* defined(CONFIG_X86) || defined (CONFIG_ARM64) */ | 
|  |  | 
|  | static int __initdata parsed_numa_memblks; | 
|  |  | 
|  | static int __init | 
|  | acpi_parse_memory_affinity(union acpi_subtable_headers * header, | 
|  | const unsigned long end) | 
|  | { | 
|  | struct acpi_srat_mem_affinity *memory_affinity; | 
|  |  | 
|  | memory_affinity = (struct acpi_srat_mem_affinity *)header; | 
|  |  | 
|  | acpi_table_print_srat_entry(&header->common); | 
|  |  | 
|  | /* let architecture-dependent part to do it */ | 
|  | if (!acpi_numa_memory_affinity_init(memory_affinity)) | 
|  | parsed_numa_memblks++; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int __init acpi_parse_srat(struct acpi_table_header *table) | 
|  | { | 
|  | struct acpi_table_srat *srat = (struct acpi_table_srat *)table; | 
|  |  | 
|  | acpi_srat_revision = srat->header.revision; | 
|  |  | 
|  | /* Real work done in acpi_table_parse_srat below. */ | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int __init | 
|  | acpi_table_parse_srat(enum acpi_srat_type id, | 
|  | acpi_tbl_entry_handler handler, unsigned int max_entries) | 
|  | { | 
|  | return acpi_table_parse_entries(ACPI_SIG_SRAT, | 
|  | sizeof(struct acpi_table_srat), id, | 
|  | handler, max_entries); | 
|  | } | 
|  |  | 
|  | int __init acpi_numa_init(void) | 
|  | { | 
|  | int i, fake_pxm, cnt = 0; | 
|  |  | 
|  | if (acpi_disabled) | 
|  | return -EINVAL; | 
|  |  | 
|  | /* | 
|  | * Should not limit number with cpu num that is from NR_CPUS or nr_cpus= | 
|  | * SRAT cpu entries could have different order with that in MADT. | 
|  | * So go over all cpu entries in SRAT to get apicid to node mapping. | 
|  | */ | 
|  |  | 
|  | /* SRAT: System Resource Affinity Table */ | 
|  | if (!acpi_table_parse(ACPI_SIG_SRAT, acpi_parse_srat)) { | 
|  | struct acpi_subtable_proc srat_proc[4]; | 
|  |  | 
|  | memset(srat_proc, 0, sizeof(srat_proc)); | 
|  | srat_proc[0].id = ACPI_SRAT_TYPE_CPU_AFFINITY; | 
|  | srat_proc[0].handler = acpi_parse_processor_affinity; | 
|  | srat_proc[1].id = ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY; | 
|  | srat_proc[1].handler = acpi_parse_x2apic_affinity; | 
|  | srat_proc[2].id = ACPI_SRAT_TYPE_GICC_AFFINITY; | 
|  | srat_proc[2].handler = acpi_parse_gicc_affinity; | 
|  | srat_proc[3].id = ACPI_SRAT_TYPE_GENERIC_AFFINITY; | 
|  | srat_proc[3].handler = acpi_parse_gi_affinity; | 
|  |  | 
|  | acpi_table_parse_entries_array(ACPI_SIG_SRAT, | 
|  | sizeof(struct acpi_table_srat), | 
|  | srat_proc, ARRAY_SIZE(srat_proc), 0); | 
|  |  | 
|  | cnt = acpi_table_parse_srat(ACPI_SRAT_TYPE_MEMORY_AFFINITY, | 
|  | acpi_parse_memory_affinity, 0); | 
|  | } | 
|  |  | 
|  | /* SLIT: System Locality Information Table */ | 
|  | acpi_table_parse(ACPI_SIG_SLIT, acpi_parse_slit); | 
|  |  | 
|  | /* | 
|  | * CXL Fixed Memory Window Structures (CFMWS) must be parsed | 
|  | * after the SRAT. Create NUMA Nodes for CXL memory ranges that | 
|  | * are defined in the CFMWS and not already defined in the SRAT. | 
|  | * Initialize a fake_pxm as the first available PXM to emulate. | 
|  | */ | 
|  |  | 
|  | /* fake_pxm is the next unused PXM value after SRAT parsing */ | 
|  | for (i = 0, fake_pxm = -1; i < MAX_NUMNODES; i++) { | 
|  | if (node_to_pxm_map[i] > fake_pxm) | 
|  | fake_pxm = node_to_pxm_map[i]; | 
|  | } | 
|  | fake_pxm++; | 
|  | acpi_table_parse_cedt(ACPI_CEDT_TYPE_CFMWS, acpi_parse_cfmws, | 
|  | &fake_pxm); | 
|  |  | 
|  | if (cnt < 0) | 
|  | return cnt; | 
|  | else if (!parsed_numa_memblks) | 
|  | return -ENOENT; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int acpi_get_pxm(acpi_handle h) | 
|  | { | 
|  | unsigned long long pxm; | 
|  | acpi_status status; | 
|  | acpi_handle handle; | 
|  | acpi_handle phandle = h; | 
|  |  | 
|  | do { | 
|  | handle = phandle; | 
|  | status = acpi_evaluate_integer(handle, "_PXM", NULL, &pxm); | 
|  | if (ACPI_SUCCESS(status)) | 
|  | return pxm; | 
|  | status = acpi_get_parent(handle, &phandle); | 
|  | } while (ACPI_SUCCESS(status)); | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | int acpi_get_node(acpi_handle handle) | 
|  | { | 
|  | int pxm; | 
|  |  | 
|  | pxm = acpi_get_pxm(handle); | 
|  |  | 
|  | return pxm_to_node(pxm); | 
|  | } | 
|  | EXPORT_SYMBOL(acpi_get_node); |