2 * Procedures for creating, accessing and interpreting the device tree.
4 * Paul Mackerras August 1996.
5 * Copyright (C) 1996-2005 Paul Mackerras.
7 * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
8 * {engebret|bergner}@us.ibm.com
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
19 #include <linux/kernel.h>
20 #include <linux/string.h>
21 #include <linux/init.h>
22 #include <linux/threads.h>
23 #include <linux/spinlock.h>
24 #include <linux/types.h>
25 #include <linux/pci.h>
26 #include <linux/stringify.h>
27 #include <linux/delay.h>
28 #include <linux/initrd.h>
29 #include <linux/bitops.h>
30 #include <linux/export.h>
31 #include <linux/kexec.h>
32 #include <linux/irq.h>
33 #include <linux/memblock.h>
35 #include <linux/of_fdt.h>
36 #include <linux/libfdt.h>
41 #include <asm/processor.h>
44 #include <asm/kdump.h>
48 #include <asm/pgtable.h>
49 #include <asm/iommu.h>
50 #include <asm/btext.h>
51 #include <asm/sections.h>
52 #include <asm/machdep.h>
53 #include <asm/pci-bridge.h>
54 #include <asm/kexec.h>
56 #include <asm/fadump.h>
57 #include <asm/debug.h>
59 #include <mm/mmu_decl.h>
62 #define DBG(fmt...) printk(KERN_ERR fmt)
68 int __initdata iommu_is_off;
69 int __initdata iommu_force_on;
70 unsigned long tce_alloc_start, tce_alloc_end;
73 static phys_addr_t first_memblock_size;
74 static int __initdata boot_cpu_count;
76 static int __init early_parse_mem(char *p)
81 memory_limit = PAGE_ALIGN(memparse(p, &p));
82 DBG("memory limit = 0x%llx\n", memory_limit);
86 early_param("mem", early_parse_mem);
89 * overlaps_initrd - check for overlap with page aligned extension of
92 static inline int overlaps_initrd(unsigned long start, unsigned long size)
94 #ifdef CONFIG_BLK_DEV_INITRD
98 return (start + size) > _ALIGN_DOWN(initrd_start, PAGE_SIZE) &&
99 start <= _ALIGN_UP(initrd_end, PAGE_SIZE);
106 * move_device_tree - move tree to an unused area, if needed.
108 * The device tree may be allocated beyond our memory limit, or inside the
109 * crash kernel region for kdump, or within the page aligned range of initrd.
110 * If so, move it out of the way.
112 static void __init move_device_tree(void)
114 unsigned long start, size;
117 DBG("-> move_device_tree\n");
119 start = __pa(initial_boot_params);
120 size = fdt_totalsize(initial_boot_params);
122 if ((memory_limit && (start + size) > PHYSICAL_START + memory_limit) ||
123 overlaps_crashkernel(start, size) ||
124 overlaps_initrd(start, size)) {
125 p = __va(memblock_alloc(size, PAGE_SIZE));
126 memcpy(p, initial_boot_params, size);
127 initial_boot_params = p;
128 DBG("Moved device tree to 0x%p\n", p);
131 DBG("<- move_device_tree\n");
135 * ibm,pa-features is a per-cpu property that contains a string of
136 * attribute descriptors, each of which has a 2 byte header plus up
137 * to 254 bytes worth of processor attribute bits. First header
138 * byte specifies the number of bytes following the header.
139 * Second header byte is an "attribute-specifier" type, of which
140 * zero is the only currently-defined value.
141 * Implementation: Pass in the byte and bit offset for the feature
142 * that we are interested in. The function will return -1 if the
143 * pa-features property is missing, or a 1/0 to indicate if the feature
144 * is supported/not supported. Note that the bit numbers are
145 * big-endian to match the definition in PAPR.
147 static struct ibm_pa_feature {
148 unsigned long cpu_features; /* CPU_FTR_xxx bit */
149 unsigned long mmu_features; /* MMU_FTR_xxx bit */
150 unsigned int cpu_user_ftrs; /* PPC_FEATURE_xxx bit */
151 unsigned int cpu_user_ftrs2; /* PPC_FEATURE2_xxx bit */
152 unsigned char pabyte; /* byte number in ibm,pa-features */
153 unsigned char pabit; /* bit number (big-endian) */
154 unsigned char invert; /* if 1, pa bit set => clear feature */
155 } ibm_pa_features[] __initdata = {
156 {0, 0, PPC_FEATURE_HAS_MMU, 0, 0, 0, 0},
157 {0, 0, PPC_FEATURE_HAS_FPU, 0, 0, 1, 0},
158 {CPU_FTR_CTRL, 0, 0, 0, 0, 3, 0},
159 {CPU_FTR_NOEXECUTE, 0, 0, 0, 0, 6, 0},
160 {CPU_FTR_NODSISRALIGN, 0, 0, 0, 1, 1, 1},
161 {0, MMU_FTR_CI_LARGE_PAGE, 0, 0, 1, 2, 0},
162 {CPU_FTR_REAL_LE, 0, PPC_FEATURE_TRUE_LE, 0, 5, 0, 0},
164 * If the kernel doesn't support TM (ie. CONFIG_PPC_TRANSACTIONAL_MEM=n),
165 * we don't want to turn on CPU_FTR_TM here, so we use CPU_FTR_TM_COMP
166 * which is 0 if the kernel doesn't support TM.
168 {CPU_FTR_TM_COMP, 0, 0, 0, 22, 0, 0},
171 static void __init scan_features(unsigned long node, const unsigned char *ftrs,
172 unsigned long tablelen,
173 struct ibm_pa_feature *fp,
174 unsigned long ft_size)
176 unsigned long i, len, bit;
178 /* find descriptor with type == 0 */
184 return; /* descriptor 0 not found */
191 /* loop over bits we know about */
192 for (i = 0; i < ft_size; ++i, ++fp) {
193 if (fp->pabyte >= ftrs[0])
195 bit = (ftrs[2 + fp->pabyte] >> (7 - fp->pabit)) & 1;
196 if (bit ^ fp->invert) {
197 cur_cpu_spec->cpu_features |= fp->cpu_features;
198 cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftrs;
199 cur_cpu_spec->cpu_user_features2 |= fp->cpu_user_ftrs2;
200 cur_cpu_spec->mmu_features |= fp->mmu_features;
202 cur_cpu_spec->cpu_features &= ~fp->cpu_features;
203 cur_cpu_spec->cpu_user_features &= ~fp->cpu_user_ftrs;
204 cur_cpu_spec->cpu_user_features2 &= ~fp->cpu_user_ftrs2;
205 cur_cpu_spec->mmu_features &= ~fp->mmu_features;
210 static void __init check_cpu_pa_features(unsigned long node)
212 const unsigned char *pa_ftrs;
215 pa_ftrs = of_get_flat_dt_prop(node, "ibm,pa-features", &tablelen);
219 scan_features(node, pa_ftrs, tablelen,
220 ibm_pa_features, ARRAY_SIZE(ibm_pa_features));
223 #ifdef CONFIG_PPC_STD_MMU_64
224 static void __init init_mmu_slb_size(unsigned long node)
226 const __be32 *slb_size_ptr;
228 slb_size_ptr = of_get_flat_dt_prop(node, "slb-size", NULL) ? :
229 of_get_flat_dt_prop(node, "ibm,slb-size", NULL);
232 mmu_slb_size = be32_to_cpup(slb_size_ptr);
235 #define init_mmu_slb_size(node) do { } while(0)
238 static struct feature_property {
241 unsigned long cpu_feature;
242 unsigned long cpu_user_ftr;
243 } feature_properties[] __initdata = {
244 #ifdef CONFIG_ALTIVEC
245 {"altivec", 0, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
246 {"ibm,vmx", 1, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
247 #endif /* CONFIG_ALTIVEC */
249 /* Yes, this _really_ is ibm,vmx == 2 to enable VSX */
250 {"ibm,vmx", 2, CPU_FTR_VSX, PPC_FEATURE_HAS_VSX},
251 #endif /* CONFIG_VSX */
253 {"ibm,dfp", 1, 0, PPC_FEATURE_HAS_DFP},
254 {"ibm,purr", 1, CPU_FTR_PURR, 0},
255 {"ibm,spurr", 1, CPU_FTR_SPURR, 0},
256 #endif /* CONFIG_PPC64 */
259 #if defined(CONFIG_44x) && defined(CONFIG_PPC_FPU)
260 static inline void identical_pvr_fixup(unsigned long node)
263 const char *model = of_get_flat_dt_prop(node, "model", NULL);
266 * Since 440GR(x)/440EP(x) processors have the same pvr,
267 * we check the node path and set bit 28 in the cur_cpu_spec
268 * pvr for EP(x) processor version. This bit is always 0 in
269 * the "real" pvr. Then we call identify_cpu again with
270 * the new logical pvr to enable FPU support.
272 if (model && strstr(model, "440EP")) {
273 pvr = cur_cpu_spec->pvr_value | 0x8;
274 identify_cpu(0, pvr);
275 DBG("Using logical pvr %x for %s\n", pvr, model);
279 #define identical_pvr_fixup(node) do { } while(0)
282 static void __init check_cpu_feature_properties(unsigned long node)
285 struct feature_property *fp = feature_properties;
288 for (i = 0; i < ARRAY_SIZE(feature_properties); ++i, ++fp) {
289 prop = of_get_flat_dt_prop(node, fp->name, NULL);
290 if (prop && be32_to_cpup(prop) >= fp->min_value) {
291 cur_cpu_spec->cpu_features |= fp->cpu_feature;
292 cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftr;
297 static int __init early_init_dt_scan_cpus(unsigned long node,
298 const char *uname, int depth,
301 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
303 const __be32 *intserv;
307 int found_thread = 0;
309 /* We are scanning "cpu" nodes only */
310 if (type == NULL || strcmp(type, "cpu") != 0)
313 /* Get physical cpuid */
314 intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
316 intserv = of_get_flat_dt_prop(node, "reg", &len);
318 nthreads = len / sizeof(int);
321 * Now see if any of these threads match our boot cpu.
322 * NOTE: This must match the parsing done in smp_setup_cpu_maps.
324 for (i = 0; i < nthreads; i++) {
326 * version 2 of the kexec param format adds the phys cpuid of
329 if (fdt_version(initial_boot_params) >= 2) {
330 if (be32_to_cpu(intserv[i]) ==
331 fdt_boot_cpuid_phys(initial_boot_params)) {
332 found = boot_cpu_count;
337 * Check if it's the boot-cpu, set it's hw index now,
338 * unfortunately this format did not support booting
339 * off secondary threads.
341 if (of_get_flat_dt_prop(node,
342 "linux,boot-cpu", NULL) != NULL)
343 found = boot_cpu_count;
346 /* logical cpu id is always 0 on UP kernels */
351 /* Not the boot CPU */
355 DBG("boot cpu: logical %d physical %d\n", found,
356 be32_to_cpu(intserv[found_thread]));
358 set_hard_smp_processor_id(found, be32_to_cpu(intserv[found_thread]));
361 * PAPR defines "logical" PVR values for cpus that
362 * meet various levels of the architecture:
363 * 0x0f000001 Architecture version 2.04
364 * 0x0f000002 Architecture version 2.05
365 * If the cpu-version property in the cpu node contains
366 * such a value, we call identify_cpu again with the
367 * logical PVR value in order to use the cpu feature
368 * bits appropriate for the architecture level.
370 * A POWER6 partition in "POWER6 architected" mode
371 * uses the 0x0f000002 PVR value; in POWER5+ mode
372 * it uses 0x0f000001.
374 prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
375 if (prop && (be32_to_cpup(prop) & 0xff000000) == 0x0f000000)
376 identify_cpu(0, be32_to_cpup(prop));
378 identical_pvr_fixup(node);
380 check_cpu_feature_properties(node);
381 check_cpu_pa_features(node);
382 init_mmu_slb_size(node);
386 cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
388 cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
393 static int __init early_init_dt_scan_chosen_ppc(unsigned long node,
395 int depth, void *data)
397 const unsigned long *lprop; /* All these set by kernel, so no need to convert endian */
399 /* Use common scan routine to determine if this is the chosen node */
400 if (early_init_dt_scan_chosen(node, uname, depth, data) == 0)
404 /* check if iommu is forced on or off */
405 if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
407 if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
411 /* mem=x on the command line is the preferred mechanism */
412 lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
414 memory_limit = *lprop;
417 lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
419 tce_alloc_start = *lprop;
420 lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
422 tce_alloc_end = *lprop;
426 lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
428 crashk_res.start = *lprop;
430 lprop = of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
432 crashk_res.end = crashk_res.start + *lprop - 1;
439 #ifdef CONFIG_PPC_PSERIES
441 * Interpret the ibm,dynamic-memory property in the
442 * /ibm,dynamic-reconfiguration-memory node.
443 * This contains a list of memory blocks along with NUMA affinity
446 static int __init early_init_dt_scan_drconf_memory(unsigned long node)
448 const __be32 *dm, *ls, *usm;
450 unsigned long n, flags;
451 u64 base, size, memblock_size;
452 unsigned int is_kexec_kdump = 0, rngs;
454 ls = of_get_flat_dt_prop(node, "ibm,lmb-size", &l);
455 if (ls == NULL || l < dt_root_size_cells * sizeof(__be32))
457 memblock_size = dt_mem_next_cell(dt_root_size_cells, &ls);
459 dm = of_get_flat_dt_prop(node, "ibm,dynamic-memory", &l);
460 if (dm == NULL || l < sizeof(__be32))
463 n = of_read_number(dm++, 1); /* number of entries */
464 if (l < (n * (dt_root_addr_cells + 4) + 1) * sizeof(__be32))
467 /* check if this is a kexec/kdump kernel. */
468 usm = of_get_flat_dt_prop(node, "linux,drconf-usable-memory",
473 for (; n != 0; --n) {
474 base = dt_mem_next_cell(dt_root_addr_cells, &dm);
475 flags = of_read_number(&dm[3], 1);
476 /* skip DRC index, pad, assoc. list index, flags */
478 /* skip this block if the reserved bit is set in flags
479 or if the block is not assigned to this partition */
480 if ((flags & DRCONF_MEM_RESERVED) ||
481 !(flags & DRCONF_MEM_ASSIGNED))
483 size = memblock_size;
485 if (is_kexec_kdump) {
487 * For each memblock in ibm,dynamic-memory, a corresponding
488 * entry in linux,drconf-usable-memory property contains
489 * a counter 'p' followed by 'p' (base, size) duple.
490 * Now read the counter from
491 * linux,drconf-usable-memory property
493 rngs = dt_mem_next_cell(dt_root_size_cells, &usm);
494 if (!rngs) /* there are no (base, size) duple */
498 if (is_kexec_kdump) {
499 base = dt_mem_next_cell(dt_root_addr_cells,
501 size = dt_mem_next_cell(dt_root_size_cells,
505 if (base >= 0x80000000ul)
507 if ((base + size) > 0x80000000ul)
508 size = 0x80000000ul - base;
510 memblock_add(base, size);
517 #define early_init_dt_scan_drconf_memory(node) 0
518 #endif /* CONFIG_PPC_PSERIES */
520 static int __init early_init_dt_scan_memory_ppc(unsigned long node,
522 int depth, void *data)
525 strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0)
526 return early_init_dt_scan_drconf_memory(node);
528 return early_init_dt_scan_memory(node, uname, depth, data);
532 * For a relocatable kernel, we need to get the memstart_addr first,
533 * then use it to calculate the virtual kernel start address. This has
534 * to happen at a very early stage (before machine_init). In this case,
535 * we just want to get the memstart_address and would not like to mess the
536 * memblock at this stage. So introduce a variable to skip the memblock_add()
539 #ifdef CONFIG_RELOCATABLE
540 static int add_mem_to_memblock = 1;
542 #define add_mem_to_memblock 1
545 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
549 if (base >= 0x80000000ul)
551 if ((base + size) > 0x80000000ul)
552 size = 0x80000000ul - base;
555 /* Keep track of the beginning of memory -and- the size of
556 * the very first block in the device-tree as it represents
557 * the RMA on ppc64 server
559 if (base < memstart_addr) {
560 memstart_addr = base;
561 first_memblock_size = size;
564 /* Add the chunk to the MEMBLOCK list */
565 if (add_mem_to_memblock)
566 memblock_add(base, size);
569 static void __init early_reserve_mem_dt(void)
571 unsigned long i, dt_root;
575 early_init_fdt_reserve_self();
576 early_init_fdt_scan_reserved_mem();
578 dt_root = of_get_flat_dt_root();
580 prop = of_get_flat_dt_prop(dt_root, "reserved-ranges", &len);
585 DBG("Found new-style reserved-ranges\n");
587 /* Each reserved range is an (address,size) pair, 2 cells each,
588 * totalling 4 cells per range. */
589 for (i = 0; i < len / (sizeof(*prop) * 4); i++) {
592 base = of_read_number(prop + (i * 4) + 0, 2);
593 size = of_read_number(prop + (i * 4) + 2, 2);
596 DBG("reserving: %llx -> %llx\n", base, size);
597 memblock_reserve(base, size);
602 static void __init early_reserve_mem(void)
606 reserve_map = (__be64 *)(((unsigned long)initial_boot_params) +
607 fdt_off_mem_rsvmap(initial_boot_params));
609 /* Look for the new "reserved-regions" property in the DT */
610 early_reserve_mem_dt();
612 #ifdef CONFIG_BLK_DEV_INITRD
613 /* Then reserve the initrd, if any */
614 if (initrd_start && (initrd_end > initrd_start)) {
615 memblock_reserve(_ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
616 _ALIGN_UP(initrd_end, PAGE_SIZE) -
617 _ALIGN_DOWN(initrd_start, PAGE_SIZE));
619 #endif /* CONFIG_BLK_DEV_INITRD */
623 * Handle the case where we might be booting from an old kexec
624 * image that setup the mem_rsvmap as pairs of 32-bit values
626 if (be64_to_cpup(reserve_map) > 0xffffffffull) {
627 u32 base_32, size_32;
628 __be32 *reserve_map_32 = (__be32 *)reserve_map;
630 DBG("Found old 32-bit reserve map\n");
633 base_32 = be32_to_cpup(reserve_map_32++);
634 size_32 = be32_to_cpup(reserve_map_32++);
637 DBG("reserving: %x -> %x\n", base_32, size_32);
638 memblock_reserve(base_32, size_32);
645 void __init early_init_devtree(void *params)
649 DBG(" -> early_init_devtree(%p)\n", params);
651 /* Too early to BUG_ON(), do it by hand */
652 if (!early_init_dt_verify(params))
653 panic("BUG: Failed verifying flat device tree, bad version?");
655 #ifdef CONFIG_PPC_RTAS
656 /* Some machines might need RTAS info for debugging, grab it now. */
657 of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
660 #ifdef CONFIG_PPC_POWERNV
661 /* Some machines might need OPAL info for debugging, grab it now. */
662 of_scan_flat_dt(early_init_dt_scan_opal, NULL);
665 #ifdef CONFIG_FA_DUMP
666 /* scan tree to see if dump is active during last boot */
667 of_scan_flat_dt(early_init_dt_scan_fw_dump, NULL);
670 /* Retrieve various informations from the /chosen node of the
671 * device-tree, including the platform type, initrd location and
672 * size, TCE reserve, and more ...
674 of_scan_flat_dt(early_init_dt_scan_chosen_ppc, boot_command_line);
676 /* Scan memory nodes and rebuild MEMBLOCKs */
677 of_scan_flat_dt(early_init_dt_scan_root, NULL);
678 of_scan_flat_dt(early_init_dt_scan_memory_ppc, NULL);
682 /* make sure we've parsed cmdline for mem= before this */
684 first_memblock_size = min_t(u64, first_memblock_size, memory_limit);
685 setup_initial_memory_limit(memstart_addr, first_memblock_size);
686 /* Reserve MEMBLOCK regions used by kernel, initrd, dt, etc... */
687 memblock_reserve(PHYSICAL_START, __pa(klimit) - PHYSICAL_START);
688 /* If relocatable, reserve first 32k for interrupt vectors etc. */
689 if (PHYSICAL_START > MEMORY_START)
690 memblock_reserve(MEMORY_START, 0x8000);
691 reserve_kdump_trampoline();
692 #ifdef CONFIG_FA_DUMP
694 * If we fail to reserve memory for firmware-assisted dump then
695 * fallback to kexec based kdump.
697 if (fadump_reserve_mem() == 0)
699 reserve_crashkernel();
702 /* Ensure that total memory size is page-aligned. */
703 limit = ALIGN(memory_limit ?: memblock_phys_mem_size(), PAGE_SIZE);
704 memblock_enforce_memory_limit(limit);
706 memblock_allow_resize();
709 DBG("Phys. mem: %llx\n", memblock_phys_mem_size());
711 /* We may need to relocate the flat tree, do it now.
712 * FIXME .. and the initrd too? */
717 DBG("Scanning CPUs ...\n");
719 /* Retrieve CPU related informations from the flat tree
720 * (altivec support, boot CPU ID, ...)
722 of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
723 if (boot_cpuid < 0) {
724 printk("Failed to identify boot CPU !\n");
728 #if defined(CONFIG_SMP) && defined(CONFIG_PPC64)
729 /* We'll later wait for secondaries to check in; there are
730 * NCPUS-1 non-boot CPUs :-)
732 spinning_secondaries = boot_cpu_count - 1;
735 #ifdef CONFIG_PPC_POWERNV
736 /* Scan and build the list of machine check recoverable ranges */
737 of_scan_flat_dt(early_init_dt_scan_recoverable_ranges, NULL);
740 DBG(" <- early_init_devtree()\n");
743 #ifdef CONFIG_RELOCATABLE
745 * This function run before early_init_devtree, so we have to init
746 * initial_boot_params.
748 void __init early_get_first_memblock_info(void *params, phys_addr_t *size)
750 /* Setup flat device-tree pointer */
751 initial_boot_params = params;
754 * Scan the memory nodes and set add_mem_to_memblock to 0 to avoid
757 add_mem_to_memblock = 0;
758 of_scan_flat_dt(early_init_dt_scan_root, NULL);
759 of_scan_flat_dt(early_init_dt_scan_memory_ppc, NULL);
760 add_mem_to_memblock = 1;
763 *size = first_memblock_size;
769 * New implementation of the OF "find" APIs, return a refcounted
770 * object, call of_node_put() when done. The device tree and list
771 * are protected by a rw_lock.
773 * Note that property management will need some locking as well,
774 * this isn't dealt with yet.
779 * of_get_ibm_chip_id - Returns the IBM "chip-id" of a device
780 * @np: device node of the device
782 * This looks for a property "ibm,chip-id" in the node or any
783 * of its parents and returns its content, or -1 if it cannot
786 int of_get_ibm_chip_id(struct device_node *np)
793 * Skiboot may produce memory nodes that contain more than one
794 * cell in chip-id, we only read the first one here.
796 if (!of_property_read_u32(np, "ibm,chip-id", &chip_id)) {
801 np = of_get_next_parent(np);
805 EXPORT_SYMBOL(of_get_ibm_chip_id);
808 * cpu_to_chip_id - Return the cpus chip-id
809 * @cpu: The logical cpu number.
811 * Return the value of the ibm,chip-id property corresponding to the given
812 * logical cpu number. If the chip-id can not be found, returns -1.
814 int cpu_to_chip_id(int cpu)
816 struct device_node *np;
818 np = of_get_cpu_node(cpu, NULL);
823 return of_get_ibm_chip_id(np);
825 EXPORT_SYMBOL(cpu_to_chip_id);
827 bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
829 return (int)phys_id == get_hard_smp_processor_id(cpu);