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v5.9
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Procedures for creating, accessing and interpreting the device tree.
  4 *
  5 * Paul Mackerras	August 1996.
  6 * Copyright (C) 1996-2005 Paul Mackerras.
  7 * 
  8 *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
  9 *    {engebret|bergner}@us.ibm.com 
 10 */
 11
 12#undef DEBUG
 13
 14#include <stdarg.h>
 15#include <linux/kernel.h>
 16#include <linux/string.h>
 17#include <linux/init.h>
 18#include <linux/threads.h>
 19#include <linux/spinlock.h>
 20#include <linux/types.h>
 21#include <linux/pci.h>
 22#include <linux/delay.h>
 23#include <linux/initrd.h>
 24#include <linux/bitops.h>
 25#include <linux/export.h>
 26#include <linux/kexec.h>
 27#include <linux/irq.h>
 28#include <linux/memblock.h>
 29#include <linux/of.h>
 30#include <linux/of_fdt.h>
 31#include <linux/libfdt.h>
 32#include <linux/cpu.h>
 33#include <linux/pgtable.h>
 
 34
 35#include <asm/prom.h>
 36#include <asm/rtas.h>
 37#include <asm/page.h>
 38#include <asm/processor.h>
 39#include <asm/irq.h>
 40#include <asm/io.h>
 41#include <asm/kdump.h>
 42#include <asm/smp.h>
 43#include <asm/mmu.h>
 44#include <asm/paca.h>
 45#include <asm/powernv.h>
 46#include <asm/iommu.h>
 47#include <asm/btext.h>
 48#include <asm/sections.h>
 49#include <asm/machdep.h>
 50#include <asm/pci-bridge.h>
 51#include <asm/kexec.h>
 52#include <asm/opal.h>
 53#include <asm/fadump.h>
 54#include <asm/epapr_hcalls.h>
 55#include <asm/firmware.h>
 56#include <asm/dt_cpu_ftrs.h>
 57#include <asm/drmem.h>
 58#include <asm/ultravisor.h>
 
 
 59
 60#include <mm/mmu_decl.h>
 61
 62#ifdef DEBUG
 63#define DBG(fmt...) printk(KERN_ERR fmt)
 64#else
 65#define DBG(fmt...)
 66#endif
 67
 
 
 68#ifdef CONFIG_PPC64
 69int __initdata iommu_is_off;
 70int __initdata iommu_force_on;
 71unsigned long tce_alloc_start, tce_alloc_end;
 72u64 ppc64_rma_size;
 
 73#endif
 74static phys_addr_t first_memblock_size;
 75static int __initdata boot_cpu_count;
 76
 77static int __init early_parse_mem(char *p)
 78{
 79	if (!p)
 80		return 1;
 81
 82	memory_limit = PAGE_ALIGN(memparse(p, &p));
 83	DBG("memory limit = 0x%llx\n", memory_limit);
 84
 85	return 0;
 86}
 87early_param("mem", early_parse_mem);
 88
 89/*
 90 * overlaps_initrd - check for overlap with page aligned extension of
 91 * initrd.
 92 */
 93static inline int overlaps_initrd(unsigned long start, unsigned long size)
 94{
 95#ifdef CONFIG_BLK_DEV_INITRD
 96	if (!initrd_start)
 97		return 0;
 98
 99	return	(start + size) > ALIGN_DOWN(initrd_start, PAGE_SIZE) &&
100			start <= ALIGN(initrd_end, PAGE_SIZE);
101#else
102	return 0;
103#endif
104}
105
106/**
107 * move_device_tree - move tree to an unused area, if needed.
108 *
109 * The device tree may be allocated beyond our memory limit, or inside the
110 * crash kernel region for kdump, or within the page aligned range of initrd.
111 * If so, move it out of the way.
112 */
113static void __init move_device_tree(void)
114{
115	unsigned long start, size;
116	void *p;
117
118	DBG("-> move_device_tree\n");
119
120	start = __pa(initial_boot_params);
121	size = fdt_totalsize(initial_boot_params);
122
123	if ((memory_limit && (start + size) > PHYSICAL_START + memory_limit) ||
124	    !memblock_is_memory(start + size - 1) ||
125	    overlaps_crashkernel(start, size) || overlaps_initrd(start, size)) {
126		p = memblock_alloc_raw(size, PAGE_SIZE);
127		if (!p)
128			panic("Failed to allocate %lu bytes to move device tree\n",
129			      size);
130		memcpy(p, initial_boot_params, size);
131		initial_boot_params = p;
132		DBG("Moved device tree to 0x%px\n", p);
133	}
134
135	DBG("<- move_device_tree\n");
136}
137
138/*
139 * ibm,pa-features is a per-cpu property that contains a string of
140 * attribute descriptors, each of which has a 2 byte header plus up
141 * to 254 bytes worth of processor attribute bits.  First header
142 * byte specifies the number of bytes following the header.
143 * Second header byte is an "attribute-specifier" type, of which
144 * zero is the only currently-defined value.
145 * Implementation:  Pass in the byte and bit offset for the feature
146 * that we are interested in.  The function will return -1 if the
147 * pa-features property is missing, or a 1/0 to indicate if the feature
148 * is supported/not supported.  Note that the bit numbers are
149 * big-endian to match the definition in PAPR.
 
 
 
150 */
151static struct ibm_pa_feature {
152	unsigned long	cpu_features;	/* CPU_FTR_xxx bit */
153	unsigned long	mmu_features;	/* MMU_FTR_xxx bit */
154	unsigned int	cpu_user_ftrs;	/* PPC_FEATURE_xxx bit */
155	unsigned int	cpu_user_ftrs2;	/* PPC_FEATURE2_xxx bit */
156	unsigned char	pabyte;		/* byte number in ibm,pa-features */
157	unsigned char	pabit;		/* bit number (big-endian) */
158	unsigned char	invert;		/* if 1, pa bit set => clear feature */
159} ibm_pa_features[] __initdata = {
 
 
160	{ .pabyte = 0,  .pabit = 0, .cpu_user_ftrs = PPC_FEATURE_HAS_MMU },
161	{ .pabyte = 0,  .pabit = 1, .cpu_user_ftrs = PPC_FEATURE_HAS_FPU },
162	{ .pabyte = 0,  .pabit = 3, .cpu_features  = CPU_FTR_CTRL },
163	{ .pabyte = 0,  .pabit = 6, .cpu_features  = CPU_FTR_NOEXECUTE },
164	{ .pabyte = 1,  .pabit = 2, .mmu_features  = MMU_FTR_CI_LARGE_PAGE },
165#ifdef CONFIG_PPC_RADIX_MMU
166	{ .pabyte = 40, .pabit = 0, .mmu_features  = MMU_FTR_TYPE_RADIX | MMU_FTR_GTSE },
167#endif
168	{ .pabyte = 1,  .pabit = 1, .invert = 1, .cpu_features = CPU_FTR_NODSISRALIGN },
169	{ .pabyte = 5,  .pabit = 0, .cpu_features  = CPU_FTR_REAL_LE,
170				    .cpu_user_ftrs = PPC_FEATURE_TRUE_LE },
171	/*
172	 * If the kernel doesn't support TM (ie CONFIG_PPC_TRANSACTIONAL_MEM=n),
173	 * we don't want to turn on TM here, so we use the *_COMP versions
174	 * which are 0 if the kernel doesn't support TM.
175	 */
176	{ .pabyte = 22, .pabit = 0, .cpu_features = CPU_FTR_TM_COMP,
177	  .cpu_user_ftrs2 = PPC_FEATURE2_HTM_COMP | PPC_FEATURE2_HTM_NOSC_COMP },
178
179	{ .pabyte = 64, .pabit = 0, .cpu_features = CPU_FTR_DAWR1 },
 
 
 
 
 
 
 
 
 
 
 
 
180};
181
182static void __init scan_features(unsigned long node, const unsigned char *ftrs,
183				 unsigned long tablelen,
184				 struct ibm_pa_feature *fp,
185				 unsigned long ft_size)
186{
187	unsigned long i, len, bit;
188
189	/* find descriptor with type == 0 */
190	for (;;) {
191		if (tablelen < 3)
192			return;
193		len = 2 + ftrs[0];
194		if (tablelen < len)
195			return;		/* descriptor 0 not found */
196		if (ftrs[1] == 0)
197			break;
198		tablelen -= len;
199		ftrs += len;
200	}
201
202	/* loop over bits we know about */
203	for (i = 0; i < ft_size; ++i, ++fp) {
204		if (fp->pabyte >= ftrs[0])
205			continue;
206		bit = (ftrs[2 + fp->pabyte] >> (7 - fp->pabit)) & 1;
207		if (bit ^ fp->invert) {
208			cur_cpu_spec->cpu_features |= fp->cpu_features;
209			cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftrs;
210			cur_cpu_spec->cpu_user_features2 |= fp->cpu_user_ftrs2;
211			cur_cpu_spec->mmu_features |= fp->mmu_features;
212		} else {
213			cur_cpu_spec->cpu_features &= ~fp->cpu_features;
214			cur_cpu_spec->cpu_user_features &= ~fp->cpu_user_ftrs;
215			cur_cpu_spec->cpu_user_features2 &= ~fp->cpu_user_ftrs2;
216			cur_cpu_spec->mmu_features &= ~fp->mmu_features;
217		}
218	}
219}
220
221static void __init check_cpu_pa_features(unsigned long node)
 
 
222{
223	const unsigned char *pa_ftrs;
224	int tablelen;
225
226	pa_ftrs = of_get_flat_dt_prop(node, "ibm,pa-features", &tablelen);
227	if (pa_ftrs == NULL)
228		return;
229
230	scan_features(node, pa_ftrs, tablelen,
231		      ibm_pa_features, ARRAY_SIZE(ibm_pa_features));
232}
233
234#ifdef CONFIG_PPC_BOOK3S_64
235static void __init init_mmu_slb_size(unsigned long node)
236{
237	const __be32 *slb_size_ptr;
238
239	slb_size_ptr = of_get_flat_dt_prop(node, "slb-size", NULL) ? :
240			of_get_flat_dt_prop(node, "ibm,slb-size", NULL);
241
242	if (slb_size_ptr)
243		mmu_slb_size = be32_to_cpup(slb_size_ptr);
244}
245#else
246#define init_mmu_slb_size(node) do { } while(0)
247#endif
248
249static struct feature_property {
250	const char *name;
251	u32 min_value;
252	unsigned long cpu_feature;
253	unsigned long cpu_user_ftr;
254} feature_properties[] __initdata = {
255#ifdef CONFIG_ALTIVEC
256	{"altivec", 0, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
257	{"ibm,vmx", 1, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
258#endif /* CONFIG_ALTIVEC */
259#ifdef CONFIG_VSX
260	/* Yes, this _really_ is ibm,vmx == 2 to enable VSX */
261	{"ibm,vmx", 2, CPU_FTR_VSX, PPC_FEATURE_HAS_VSX},
262#endif /* CONFIG_VSX */
263#ifdef CONFIG_PPC64
264	{"ibm,dfp", 1, 0, PPC_FEATURE_HAS_DFP},
265	{"ibm,purr", 1, CPU_FTR_PURR, 0},
266	{"ibm,spurr", 1, CPU_FTR_SPURR, 0},
267#endif /* CONFIG_PPC64 */
268};
269
270#if defined(CONFIG_44x) && defined(CONFIG_PPC_FPU)
271static inline void identical_pvr_fixup(unsigned long node)
272{
273	unsigned int pvr;
274	const char *model = of_get_flat_dt_prop(node, "model", NULL);
275
276	/*
277	 * Since 440GR(x)/440EP(x) processors have the same pvr,
278	 * we check the node path and set bit 28 in the cur_cpu_spec
279	 * pvr for EP(x) processor version. This bit is always 0 in
280	 * the "real" pvr. Then we call identify_cpu again with
281	 * the new logical pvr to enable FPU support.
282	 */
283	if (model && strstr(model, "440EP")) {
284		pvr = cur_cpu_spec->pvr_value | 0x8;
285		identify_cpu(0, pvr);
286		DBG("Using logical pvr %x for %s\n", pvr, model);
287	}
288}
289#else
290#define identical_pvr_fixup(node) do { } while(0)
291#endif
292
293static void __init check_cpu_feature_properties(unsigned long node)
294{
295	int i;
296	struct feature_property *fp = feature_properties;
297	const __be32 *prop;
298
299	for (i = 0; i < (int)ARRAY_SIZE(feature_properties); ++i, ++fp) {
300		prop = of_get_flat_dt_prop(node, fp->name, NULL);
301		if (prop && be32_to_cpup(prop) >= fp->min_value) {
302			cur_cpu_spec->cpu_features |= fp->cpu_feature;
303			cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftr;
304		}
305	}
306}
307
308static int __init early_init_dt_scan_cpus(unsigned long node,
309					  const char *uname, int depth,
310					  void *data)
311{
312	const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
313	const __be32 *prop;
314	const __be32 *intserv;
315	int i, nthreads;
316	int len;
317	int found = -1;
318	int found_thread = 0;
319
320	/* We are scanning "cpu" nodes only */
321	if (type == NULL || strcmp(type, "cpu") != 0)
322		return 0;
323
 
 
 
324	/* Get physical cpuid */
325	intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
326	if (!intserv)
327		intserv = of_get_flat_dt_prop(node, "reg", &len);
328
329	nthreads = len / sizeof(int);
330
331	/*
332	 * Now see if any of these threads match our boot cpu.
333	 * NOTE: This must match the parsing done in smp_setup_cpu_maps.
334	 */
335	for (i = 0; i < nthreads; i++) {
336		if (be32_to_cpu(intserv[i]) ==
337			fdt_boot_cpuid_phys(initial_boot_params)) {
338			found = boot_cpu_count;
339			found_thread = i;
340		}
341#ifdef CONFIG_SMP
342		/* logical cpu id is always 0 on UP kernels */
343		boot_cpu_count++;
344#endif
345	}
346
347	/* Not the boot CPU */
348	if (found < 0)
349		return 0;
350
351	DBG("boot cpu: logical %d physical %d\n", found,
352	    be32_to_cpu(intserv[found_thread]));
353	boot_cpuid = found;
354
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
355	/*
356	 * PAPR defines "logical" PVR values for cpus that
357	 * meet various levels of the architecture:
358	 * 0x0f000001	Architecture version 2.04
359	 * 0x0f000002	Architecture version 2.05
360	 * If the cpu-version property in the cpu node contains
361	 * such a value, we call identify_cpu again with the
362	 * logical PVR value in order to use the cpu feature
363	 * bits appropriate for the architecture level.
364	 *
365	 * A POWER6 partition in "POWER6 architected" mode
366	 * uses the 0x0f000002 PVR value; in POWER5+ mode
367	 * it uses 0x0f000001.
368	 *
369	 * If we're using device tree CPU feature discovery then we don't
370	 * support the cpu-version property, and it's the responsibility of the
371	 * firmware/hypervisor to provide the correct feature set for the
372	 * architecture level via the ibm,powerpc-cpu-features binding.
373	 */
374	if (!dt_cpu_ftrs_in_use()) {
375		prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
376		if (prop && (be32_to_cpup(prop) & 0xff000000) == 0x0f000000)
377			identify_cpu(0, be32_to_cpup(prop));
 
 
378
379		check_cpu_feature_properties(node);
380		check_cpu_pa_features(node);
 
 
 
381	}
382
383	identical_pvr_fixup(node);
384	init_mmu_slb_size(node);
385
386#ifdef CONFIG_PPC64
387	if (nthreads == 1)
388		cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
389	else if (!dt_cpu_ftrs_in_use())
390		cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
391	allocate_paca(boot_cpuid);
392#endif
393	set_hard_smp_processor_id(found, be32_to_cpu(intserv[found_thread]));
394
395	return 0;
396}
397
398static int __init early_init_dt_scan_chosen_ppc(unsigned long node,
399						const char *uname,
400						int depth, void *data)
401{
402	const unsigned long *lprop; /* All these set by kernel, so no need to convert endian */
403
404	/* Use common scan routine to determine if this is the chosen node */
405	if (early_init_dt_scan_chosen(node, uname, depth, data) == 0)
406		return 0;
407
408#ifdef CONFIG_PPC64
409	/* check if iommu is forced on or off */
410	if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
411		iommu_is_off = 1;
412	if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
413		iommu_force_on = 1;
414#endif
415
416	/* mem=x on the command line is the preferred mechanism */
417	lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
418	if (lprop)
419		memory_limit = *lprop;
420
421#ifdef CONFIG_PPC64
422	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
423	if (lprop)
424		tce_alloc_start = *lprop;
425	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
426	if (lprop)
427		tce_alloc_end = *lprop;
428#endif
429
430#ifdef CONFIG_KEXEC_CORE
431	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
432	if (lprop)
433		crashk_res.start = *lprop;
434
435	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
436	if (lprop)
437		crashk_res.end = crashk_res.start + *lprop - 1;
438#endif
439
440	/* break now */
441	return 1;
442}
443
444/*
445 * Compare the range against max mem limit and update
446 * size if it cross the limit.
447 */
448
449#ifdef CONFIG_SPARSEMEM
450static bool validate_mem_limit(u64 base, u64 *size)
451{
452	u64 max_mem = 1UL << (MAX_PHYSMEM_BITS);
453
454	if (base >= max_mem)
455		return false;
456	if ((base + *size) > max_mem)
457		*size = max_mem - base;
458	return true;
459}
460#else
461static bool validate_mem_limit(u64 base, u64 *size)
462{
463	return true;
464}
465#endif
466
467#ifdef CONFIG_PPC_PSERIES
468/*
469 * Interpret the ibm dynamic reconfiguration memory LMBs.
470 * This contains a list of memory blocks along with NUMA affinity
471 * information.
472 */
473static int  __init early_init_drmem_lmb(struct drmem_lmb *lmb,
474					const __be32 **usm,
475					void *data)
476{
477	u64 base, size;
478	int is_kexec_kdump = 0, rngs;
479
480	base = lmb->base_addr;
481	size = drmem_lmb_size();
482	rngs = 1;
483
484	/*
485	 * Skip this block if the reserved bit is set in flags
486	 * or if the block is not assigned to this partition.
487	 */
488	if ((lmb->flags & DRCONF_MEM_RESERVED) ||
489	    !(lmb->flags & DRCONF_MEM_ASSIGNED))
490		return 0;
491
492	if (*usm)
493		is_kexec_kdump = 1;
494
495	if (is_kexec_kdump) {
496		/*
497		 * For each memblock in ibm,dynamic-memory, a
498		 * corresponding entry in linux,drconf-usable-memory
499		 * property contains a counter 'p' followed by 'p'
500		 * (base, size) duple. Now read the counter from
501		 * linux,drconf-usable-memory property
502		 */
503		rngs = dt_mem_next_cell(dt_root_size_cells, usm);
504		if (!rngs) /* there are no (base, size) duple */
505			return 0;
506	}
507
508	do {
509		if (is_kexec_kdump) {
510			base = dt_mem_next_cell(dt_root_addr_cells, usm);
511			size = dt_mem_next_cell(dt_root_size_cells, usm);
512		}
513
514		if (iommu_is_off) {
515			if (base >= 0x80000000ul)
516				continue;
517			if ((base + size) > 0x80000000ul)
518				size = 0x80000000ul - base;
519		}
520
521		if (!validate_mem_limit(base, &size))
522			continue;
523
524		DBG("Adding: %llx -> %llx\n", base, size);
525		memblock_add(base, size);
526
527		if (lmb->flags & DRCONF_MEM_HOTREMOVABLE)
528			memblock_mark_hotplug(base, size);
529	} while (--rngs);
530
531	return 0;
532}
533#endif /* CONFIG_PPC_PSERIES */
534
535static int __init early_init_dt_scan_memory_ppc(unsigned long node,
536						const char *uname,
537						int depth, void *data)
538{
539#ifdef CONFIG_PPC_PSERIES
540	if (depth == 1 &&
541	    strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0) {
 
 
542		walk_drmem_lmbs_early(node, NULL, early_init_drmem_lmb);
543		return 0;
544	}
545#endif
546	
547	return early_init_dt_scan_memory(node, uname, depth, data);
548}
549
550/*
551 * For a relocatable kernel, we need to get the memstart_addr first,
552 * then use it to calculate the virtual kernel start address. This has
553 * to happen at a very early stage (before machine_init). In this case,
554 * we just want to get the memstart_address and would not like to mess the
555 * memblock at this stage. So introduce a variable to skip the memblock_add()
556 * for this reason.
557 */
558#ifdef CONFIG_RELOCATABLE
559static int add_mem_to_memblock = 1;
560#else
561#define add_mem_to_memblock 1
562#endif
563
564void __init early_init_dt_add_memory_arch(u64 base, u64 size)
565{
566#ifdef CONFIG_PPC64
567	if (iommu_is_off) {
568		if (base >= 0x80000000ul)
569			return;
570		if ((base + size) > 0x80000000ul)
571			size = 0x80000000ul - base;
572	}
573#endif
574	/* Keep track of the beginning of memory -and- the size of
575	 * the very first block in the device-tree as it represents
576	 * the RMA on ppc64 server
577	 */
578	if (base < memstart_addr) {
579		memstart_addr = base;
580		first_memblock_size = size;
581	}
582
583	/* Add the chunk to the MEMBLOCK list */
584	if (add_mem_to_memblock) {
585		if (validate_mem_limit(base, &size))
586			memblock_add(base, size);
587	}
588}
589
590static void __init early_reserve_mem_dt(void)
591{
592	unsigned long i, dt_root;
593	int len;
594	const __be32 *prop;
595
596	early_init_fdt_reserve_self();
597	early_init_fdt_scan_reserved_mem();
598
599	dt_root = of_get_flat_dt_root();
600
601	prop = of_get_flat_dt_prop(dt_root, "reserved-ranges", &len);
602
603	if (!prop)
604		return;
605
606	DBG("Found new-style reserved-ranges\n");
607
608	/* Each reserved range is an (address,size) pair, 2 cells each,
609	 * totalling 4 cells per range. */
610	for (i = 0; i < len / (sizeof(*prop) * 4); i++) {
611		u64 base, size;
612
613		base = of_read_number(prop + (i * 4) + 0, 2);
614		size = of_read_number(prop + (i * 4) + 2, 2);
615
616		if (size) {
617			DBG("reserving: %llx -> %llx\n", base, size);
618			memblock_reserve(base, size);
619		}
620	}
621}
622
623static void __init early_reserve_mem(void)
624{
625	__be64 *reserve_map;
626
627	reserve_map = (__be64 *)(((unsigned long)initial_boot_params) +
628			fdt_off_mem_rsvmap(initial_boot_params));
629
630	/* Look for the new "reserved-regions" property in the DT */
631	early_reserve_mem_dt();
632
633#ifdef CONFIG_BLK_DEV_INITRD
634	/* Then reserve the initrd, if any */
635	if (initrd_start && (initrd_end > initrd_start)) {
636		memblock_reserve(ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
637			ALIGN(initrd_end, PAGE_SIZE) -
638			ALIGN_DOWN(initrd_start, PAGE_SIZE));
639	}
640#endif /* CONFIG_BLK_DEV_INITRD */
641
642#ifdef CONFIG_PPC32
 
 
643	/* 
644	 * Handle the case where we might be booting from an old kexec
645	 * image that setup the mem_rsvmap as pairs of 32-bit values
646	 */
647	if (be64_to_cpup(reserve_map) > 0xffffffffull) {
648		u32 base_32, size_32;
649		__be32 *reserve_map_32 = (__be32 *)reserve_map;
650
651		DBG("Found old 32-bit reserve map\n");
652
653		while (1) {
654			base_32 = be32_to_cpup(reserve_map_32++);
655			size_32 = be32_to_cpup(reserve_map_32++);
656			if (size_32 == 0)
657				break;
658			DBG("reserving: %x -> %x\n", base_32, size_32);
659			memblock_reserve(base_32, size_32);
660		}
661		return;
662	}
663#endif
664}
665
666#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
667static bool tm_disabled __initdata;
668
669static int __init parse_ppc_tm(char *str)
670{
671	bool res;
672
673	if (kstrtobool(str, &res))
674		return -EINVAL;
675
676	tm_disabled = !res;
677
678	return 0;
679}
680early_param("ppc_tm", parse_ppc_tm);
681
682static void __init tm_init(void)
683{
684	if (tm_disabled) {
685		pr_info("Disabling hardware transactional memory (HTM)\n");
686		cur_cpu_spec->cpu_user_features2 &=
687			~(PPC_FEATURE2_HTM_NOSC | PPC_FEATURE2_HTM);
688		cur_cpu_spec->cpu_features &= ~CPU_FTR_TM;
689		return;
690	}
691
692	pnv_tm_init();
693}
694#else
695static void tm_init(void) { }
696#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
697
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
698#ifdef CONFIG_PPC64
699static void __init save_fscr_to_task(void)
700{
701	/*
702	 * Ensure the init_task (pid 0, aka swapper) uses the value of FSCR we
703	 * have configured via the device tree features or via __init_FSCR().
704	 * That value will then be propagated to pid 1 (init) and all future
705	 * processes.
706	 */
707	if (early_cpu_has_feature(CPU_FTR_ARCH_207S))
708		init_task.thread.fscr = mfspr(SPRN_FSCR);
709}
710#else
711static inline void save_fscr_to_task(void) {};
712#endif
713
714
715void __init early_init_devtree(void *params)
716{
717	phys_addr_t limit;
718
719	DBG(" -> early_init_devtree(%px)\n", params);
720
721	/* Too early to BUG_ON(), do it by hand */
722	if (!early_init_dt_verify(params))
723		panic("BUG: Failed verifying flat device tree, bad version?");
724
 
 
725#ifdef CONFIG_PPC_RTAS
726	/* Some machines might need RTAS info for debugging, grab it now. */
727	of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
728#endif
729
730#ifdef CONFIG_PPC_POWERNV
731	/* Some machines might need OPAL info for debugging, grab it now. */
732	of_scan_flat_dt(early_init_dt_scan_opal, NULL);
733
734	/* Scan tree for ultravisor feature */
735	of_scan_flat_dt(early_init_dt_scan_ultravisor, NULL);
736#endif
737
738#if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)
739	/* scan tree to see if dump is active during last boot */
740	of_scan_flat_dt(early_init_dt_scan_fw_dump, NULL);
741#endif
742
743	/* Retrieve various informations from the /chosen node of the
744	 * device-tree, including the platform type, initrd location and
745	 * size, TCE reserve, and more ...
746	 */
747	of_scan_flat_dt(early_init_dt_scan_chosen_ppc, boot_command_line);
748
749	/* Scan memory nodes and rebuild MEMBLOCKs */
750	of_scan_flat_dt(early_init_dt_scan_root, NULL);
751	of_scan_flat_dt(early_init_dt_scan_memory_ppc, NULL);
752
 
 
 
 
 
 
 
753	parse_early_param();
754
755	/* make sure we've parsed cmdline for mem= before this */
756	if (memory_limit)
757		first_memblock_size = min_t(u64, first_memblock_size, memory_limit);
758	setup_initial_memory_limit(memstart_addr, first_memblock_size);
759	/* Reserve MEMBLOCK regions used by kernel, initrd, dt, etc... */
760	memblock_reserve(PHYSICAL_START, __pa(klimit) - PHYSICAL_START);
761	/* If relocatable, reserve first 32k for interrupt vectors etc. */
762	if (PHYSICAL_START > MEMORY_START)
763		memblock_reserve(MEMORY_START, 0x8000);
764	reserve_kdump_trampoline();
765#if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)
766	/*
767	 * If we fail to reserve memory for firmware-assisted dump then
768	 * fallback to kexec based kdump.
769	 */
770	if (fadump_reserve_mem() == 0)
771#endif
772		reserve_crashkernel();
773	early_reserve_mem();
774
775	/* Ensure that total memory size is page-aligned. */
776	limit = ALIGN(memory_limit ?: memblock_phys_mem_size(), PAGE_SIZE);
777	memblock_enforce_memory_limit(limit);
778
 
 
 
 
 
779	memblock_allow_resize();
780	memblock_dump_all();
781
782	DBG("Phys. mem: %llx\n", (unsigned long long)memblock_phys_mem_size());
783
784	/* We may need to relocate the flat tree, do it now.
785	 * FIXME .. and the initrd too? */
786	move_device_tree();
787
788	allocate_paca_ptrs();
789
790	DBG("Scanning CPUs ...\n");
791
792	dt_cpu_ftrs_scan();
793
 
 
 
794	/* Retrieve CPU related informations from the flat tree
795	 * (altivec support, boot CPU ID, ...)
796	 */
797	of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
798	if (boot_cpuid < 0) {
799		printk("Failed to identify boot CPU !\n");
800		BUG();
801	}
802
803	save_fscr_to_task();
804
805#if defined(CONFIG_SMP) && defined(CONFIG_PPC64)
806	/* We'll later wait for secondaries to check in; there are
807	 * NCPUS-1 non-boot CPUs  :-)
808	 */
809	spinning_secondaries = boot_cpu_count - 1;
810#endif
811
812	mmu_early_init_devtree();
813
814#ifdef CONFIG_PPC_POWERNV
815	/* Scan and build the list of machine check recoverable ranges */
816	of_scan_flat_dt(early_init_dt_scan_recoverable_ranges, NULL);
817#endif
818	epapr_paravirt_early_init();
819
820	/* Now try to figure out if we are running on LPAR and so on */
821	pseries_probe_fw_features();
822
823	/*
824	 * Initialize pkey features and default AMR/IAMR values
825	 */
826	pkey_early_init_devtree();
827
828#ifdef CONFIG_PPC_PS3
829	/* Identify PS3 firmware */
830	if (of_flat_dt_is_compatible(of_get_flat_dt_root(), "sony,ps3"))
831		powerpc_firmware_features |= FW_FEATURE_PS3_POSSIBLE;
832#endif
833
 
 
 
834	tm_init();
835
836	DBG(" <- early_init_devtree()\n");
837}
838
839#ifdef CONFIG_RELOCATABLE
840/*
841 * This function run before early_init_devtree, so we have to init
842 * initial_boot_params.
843 */
844void __init early_get_first_memblock_info(void *params, phys_addr_t *size)
845{
846	/* Setup flat device-tree pointer */
847	initial_boot_params = params;
848
849	/*
850	 * Scan the memory nodes and set add_mem_to_memblock to 0 to avoid
851	 * mess the memblock.
852	 */
853	add_mem_to_memblock = 0;
854	of_scan_flat_dt(early_init_dt_scan_root, NULL);
855	of_scan_flat_dt(early_init_dt_scan_memory_ppc, NULL);
856	add_mem_to_memblock = 1;
857
858	if (size)
859		*size = first_memblock_size;
860}
861#endif
862
863/*******
864 *
865 * New implementation of the OF "find" APIs, return a refcounted
866 * object, call of_node_put() when done.  The device tree and list
867 * are protected by a rw_lock.
868 *
869 * Note that property management will need some locking as well,
870 * this isn't dealt with yet.
871 *
872 *******/
873
874/**
875 * of_get_ibm_chip_id - Returns the IBM "chip-id" of a device
876 * @np: device node of the device
877 *
878 * This looks for a property "ibm,chip-id" in the node or any
879 * of its parents and returns its content, or -1 if it cannot
880 * be found.
881 */
882int of_get_ibm_chip_id(struct device_node *np)
883{
884	of_node_get(np);
885	while (np) {
886		u32 chip_id;
887
888		/*
889		 * Skiboot may produce memory nodes that contain more than one
890		 * cell in chip-id, we only read the first one here.
891		 */
892		if (!of_property_read_u32(np, "ibm,chip-id", &chip_id)) {
893			of_node_put(np);
894			return chip_id;
895		}
896
897		np = of_get_next_parent(np);
898	}
899	return -1;
900}
901EXPORT_SYMBOL(of_get_ibm_chip_id);
902
903/**
904 * cpu_to_chip_id - Return the cpus chip-id
905 * @cpu: The logical cpu number.
906 *
907 * Return the value of the ibm,chip-id property corresponding to the given
908 * logical cpu number. If the chip-id can not be found, returns -1.
909 */
910int cpu_to_chip_id(int cpu)
911{
912	struct device_node *np;
 
 
 
 
 
913
914	np = of_get_cpu_node(cpu, NULL);
915	if (!np)
916		return -1;
 
 
 
 
 
917
918	of_node_put(np);
919	return of_get_ibm_chip_id(np);
920}
921EXPORT_SYMBOL(cpu_to_chip_id);
922
923bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
924{
925#ifdef CONFIG_SMP
926	/*
927	 * Early firmware scanning must use this rather than
928	 * get_hard_smp_processor_id because we don't have pacas allocated
929	 * until memory topology is discovered.
930	 */
931	if (cpu_to_phys_id != NULL)
932		return (int)phys_id == cpu_to_phys_id[cpu];
933#endif
934
935	return (int)phys_id == get_hard_smp_processor_id(cpu);
936}
v6.9.4
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Procedures for creating, accessing and interpreting the device tree.
   4 *
   5 * Paul Mackerras	August 1996.
   6 * Copyright (C) 1996-2005 Paul Mackerras.
   7 * 
   8 *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
   9 *    {engebret|bergner}@us.ibm.com 
  10 */
  11
  12#undef DEBUG
  13
 
  14#include <linux/kernel.h>
  15#include <linux/string.h>
  16#include <linux/init.h>
  17#include <linux/threads.h>
  18#include <linux/spinlock.h>
  19#include <linux/types.h>
  20#include <linux/pci.h>
  21#include <linux/delay.h>
  22#include <linux/initrd.h>
  23#include <linux/bitops.h>
  24#include <linux/export.h>
  25#include <linux/kexec.h>
  26#include <linux/irq.h>
  27#include <linux/memblock.h>
  28#include <linux/of.h>
  29#include <linux/of_fdt.h>
  30#include <linux/libfdt.h>
  31#include <linux/cpu.h>
  32#include <linux/pgtable.h>
  33#include <linux/seq_buf.h>
  34
 
  35#include <asm/rtas.h>
  36#include <asm/page.h>
  37#include <asm/processor.h>
  38#include <asm/irq.h>
  39#include <asm/io.h>
  40#include <asm/kdump.h>
  41#include <asm/smp.h>
  42#include <asm/mmu.h>
  43#include <asm/paca.h>
  44#include <asm/powernv.h>
  45#include <asm/iommu.h>
  46#include <asm/btext.h>
  47#include <asm/sections.h>
  48#include <asm/setup.h>
  49#include <asm/pci-bridge.h>
  50#include <asm/kexec.h>
  51#include <asm/opal.h>
  52#include <asm/fadump.h>
  53#include <asm/epapr_hcalls.h>
  54#include <asm/firmware.h>
  55#include <asm/dt_cpu_ftrs.h>
  56#include <asm/drmem.h>
  57#include <asm/ultravisor.h>
  58#include <asm/prom.h>
  59#include <asm/plpks.h>
  60
  61#include <mm/mmu_decl.h>
  62
  63#ifdef DEBUG
  64#define DBG(fmt...) printk(KERN_ERR fmt)
  65#else
  66#define DBG(fmt...)
  67#endif
  68
  69int *chip_id_lookup_table;
  70
  71#ifdef CONFIG_PPC64
  72int __initdata iommu_is_off;
  73int __initdata iommu_force_on;
  74unsigned long tce_alloc_start, tce_alloc_end;
  75u64 ppc64_rma_size;
  76unsigned int boot_cpu_node_count __ro_after_init;
  77#endif
  78static phys_addr_t first_memblock_size;
  79static int __initdata boot_cpu_count;
  80
  81static int __init early_parse_mem(char *p)
  82{
  83	if (!p)
  84		return 1;
  85
  86	memory_limit = PAGE_ALIGN(memparse(p, &p));
  87	DBG("memory limit = 0x%llx\n", memory_limit);
  88
  89	return 0;
  90}
  91early_param("mem", early_parse_mem);
  92
  93/*
  94 * overlaps_initrd - check for overlap with page aligned extension of
  95 * initrd.
  96 */
  97static inline int overlaps_initrd(unsigned long start, unsigned long size)
  98{
  99#ifdef CONFIG_BLK_DEV_INITRD
 100	if (!initrd_start)
 101		return 0;
 102
 103	return	(start + size) > ALIGN_DOWN(initrd_start, PAGE_SIZE) &&
 104			start <= ALIGN(initrd_end, PAGE_SIZE);
 105#else
 106	return 0;
 107#endif
 108}
 109
 110/**
 111 * move_device_tree - move tree to an unused area, if needed.
 112 *
 113 * The device tree may be allocated beyond our memory limit, or inside the
 114 * crash kernel region for kdump, or within the page aligned range of initrd.
 115 * If so, move it out of the way.
 116 */
 117static void __init move_device_tree(void)
 118{
 119	unsigned long start, size;
 120	void *p;
 121
 122	DBG("-> move_device_tree\n");
 123
 124	start = __pa(initial_boot_params);
 125	size = fdt_totalsize(initial_boot_params);
 126
 127	if ((memory_limit && (start + size) > PHYSICAL_START + memory_limit) ||
 128	    !memblock_is_memory(start + size - 1) ||
 129	    overlaps_crashkernel(start, size) || overlaps_initrd(start, size)) {
 130		p = memblock_alloc_raw(size, PAGE_SIZE);
 131		if (!p)
 132			panic("Failed to allocate %lu bytes to move device tree\n",
 133			      size);
 134		memcpy(p, initial_boot_params, size);
 135		initial_boot_params = p;
 136		DBG("Moved device tree to 0x%px\n", p);
 137	}
 138
 139	DBG("<- move_device_tree\n");
 140}
 141
 142/*
 143 * ibm,pa/pi-features is a per-cpu property that contains a string of
 144 * attribute descriptors, each of which has a 2 byte header plus up
 145 * to 254 bytes worth of processor attribute bits.  First header
 146 * byte specifies the number of bytes following the header.
 147 * Second header byte is an "attribute-specifier" type, of which
 148 * zero is the only currently-defined value.
 149 * Implementation:  Pass in the byte and bit offset for the feature
 150 * that we are interested in.  The function will return -1 if the
 151 * pa-features property is missing, or a 1/0 to indicate if the feature
 152 * is supported/not supported.  Note that the bit numbers are
 153 * big-endian to match the definition in PAPR.
 154 * Note: the 'clear' flag clears the feature if the bit is set in the
 155 * ibm,pa/pi-features property, it does not set the feature if the
 156 * bit is clear.
 157 */
 158struct ibm_feature {
 159	unsigned long	cpu_features;	/* CPU_FTR_xxx bit */
 160	unsigned long	mmu_features;	/* MMU_FTR_xxx bit */
 161	unsigned int	cpu_user_ftrs;	/* PPC_FEATURE_xxx bit */
 162	unsigned int	cpu_user_ftrs2;	/* PPC_FEATURE2_xxx bit */
 163	unsigned char	pabyte;		/* byte number in ibm,pa/pi-features */
 164	unsigned char	pabit;		/* bit number (big-endian) */
 165	unsigned char	clear;		/* if 1, pa bit set => clear feature */
 166};
 167
 168static struct ibm_feature ibm_pa_features[] __initdata = {
 169	{ .pabyte = 0,  .pabit = 0, .cpu_user_ftrs = PPC_FEATURE_HAS_MMU },
 170	{ .pabyte = 0,  .pabit = 1, .cpu_user_ftrs = PPC_FEATURE_HAS_FPU },
 171	{ .pabyte = 0,  .pabit = 3, .cpu_features  = CPU_FTR_CTRL },
 172	{ .pabyte = 0,  .pabit = 6, .cpu_features  = CPU_FTR_NOEXECUTE },
 173	{ .pabyte = 1,  .pabit = 2, .mmu_features  = MMU_FTR_CI_LARGE_PAGE },
 174#ifdef CONFIG_PPC_RADIX_MMU
 175	{ .pabyte = 40, .pabit = 0, .mmu_features  = MMU_FTR_TYPE_RADIX | MMU_FTR_GTSE },
 176#endif
 
 177	{ .pabyte = 5,  .pabit = 0, .cpu_features  = CPU_FTR_REAL_LE,
 178				    .cpu_user_ftrs = PPC_FEATURE_TRUE_LE },
 179	/*
 180	 * If the kernel doesn't support TM (ie CONFIG_PPC_TRANSACTIONAL_MEM=n),
 181	 * we don't want to turn on TM here, so we use the *_COMP versions
 182	 * which are 0 if the kernel doesn't support TM.
 183	 */
 184	{ .pabyte = 22, .pabit = 0, .cpu_features = CPU_FTR_TM_COMP,
 185	  .cpu_user_ftrs2 = PPC_FEATURE2_HTM_COMP | PPC_FEATURE2_HTM_NOSC_COMP },
 186
 187	{ .pabyte = 64, .pabit = 0, .cpu_features = CPU_FTR_DAWR1 },
 188	{ .pabyte = 68, .pabit = 5, .cpu_features = CPU_FTR_DEXCR_NPHIE },
 189};
 190
 191/*
 192 * ibm,pi-features property provides the support of processor specific
 193 * options not described in ibm,pa-features. Right now use byte 0, bit 3
 194 * which indicates the occurrence of DSI interrupt when the paste operation
 195 * on the suspended NX window.
 196 */
 197static struct ibm_feature ibm_pi_features[] __initdata = {
 198	{ .pabyte = 0, .pabit = 3, .mmu_features  = MMU_FTR_NX_DSI },
 199	{ .pabyte = 0, .pabit = 4, .cpu_features  = CPU_FTR_DBELL, .clear = 1 },
 200};
 201
 202static void __init scan_features(unsigned long node, const unsigned char *ftrs,
 203				 unsigned long tablelen,
 204				 struct ibm_feature *fp,
 205				 unsigned long ft_size)
 206{
 207	unsigned long i, len, bit;
 208
 209	/* find descriptor with type == 0 */
 210	for (;;) {
 211		if (tablelen < 3)
 212			return;
 213		len = 2 + ftrs[0];
 214		if (tablelen < len)
 215			return;		/* descriptor 0 not found */
 216		if (ftrs[1] == 0)
 217			break;
 218		tablelen -= len;
 219		ftrs += len;
 220	}
 221
 222	/* loop over bits we know about */
 223	for (i = 0; i < ft_size; ++i, ++fp) {
 224		if (fp->pabyte >= ftrs[0])
 225			continue;
 226		bit = (ftrs[2 + fp->pabyte] >> (7 - fp->pabit)) & 1;
 227		if (bit && !fp->clear) {
 228			cur_cpu_spec->cpu_features |= fp->cpu_features;
 229			cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftrs;
 230			cur_cpu_spec->cpu_user_features2 |= fp->cpu_user_ftrs2;
 231			cur_cpu_spec->mmu_features |= fp->mmu_features;
 232		} else if (bit == fp->clear) {
 233			cur_cpu_spec->cpu_features &= ~fp->cpu_features;
 234			cur_cpu_spec->cpu_user_features &= ~fp->cpu_user_ftrs;
 235			cur_cpu_spec->cpu_user_features2 &= ~fp->cpu_user_ftrs2;
 236			cur_cpu_spec->mmu_features &= ~fp->mmu_features;
 237		}
 238	}
 239}
 240
 241static void __init check_cpu_features(unsigned long node, char *name,
 242				      struct ibm_feature *fp,
 243				      unsigned long size)
 244{
 245	const unsigned char *pa_ftrs;
 246	int tablelen;
 247
 248	pa_ftrs = of_get_flat_dt_prop(node, name, &tablelen);
 249	if (pa_ftrs == NULL)
 250		return;
 251
 252	scan_features(node, pa_ftrs, tablelen, fp, size);
 
 253}
 254
 255#ifdef CONFIG_PPC_64S_HASH_MMU
 256static void __init init_mmu_slb_size(unsigned long node)
 257{
 258	const __be32 *slb_size_ptr;
 259
 260	slb_size_ptr = of_get_flat_dt_prop(node, "slb-size", NULL) ? :
 261			of_get_flat_dt_prop(node, "ibm,slb-size", NULL);
 262
 263	if (slb_size_ptr)
 264		mmu_slb_size = be32_to_cpup(slb_size_ptr);
 265}
 266#else
 267#define init_mmu_slb_size(node) do { } while(0)
 268#endif
 269
 270static struct feature_property {
 271	const char *name;
 272	u32 min_value;
 273	unsigned long cpu_feature;
 274	unsigned long cpu_user_ftr;
 275} feature_properties[] __initdata = {
 276#ifdef CONFIG_ALTIVEC
 277	{"altivec", 0, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
 278	{"ibm,vmx", 1, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
 279#endif /* CONFIG_ALTIVEC */
 280#ifdef CONFIG_VSX
 281	/* Yes, this _really_ is ibm,vmx == 2 to enable VSX */
 282	{"ibm,vmx", 2, CPU_FTR_VSX, PPC_FEATURE_HAS_VSX},
 283#endif /* CONFIG_VSX */
 284#ifdef CONFIG_PPC64
 285	{"ibm,dfp", 1, 0, PPC_FEATURE_HAS_DFP},
 286	{"ibm,purr", 1, CPU_FTR_PURR, 0},
 287	{"ibm,spurr", 1, CPU_FTR_SPURR, 0},
 288#endif /* CONFIG_PPC64 */
 289};
 290
 291#if defined(CONFIG_44x) && defined(CONFIG_PPC_FPU)
 292static __init void identical_pvr_fixup(unsigned long node)
 293{
 294	unsigned int pvr;
 295	const char *model = of_get_flat_dt_prop(node, "model", NULL);
 296
 297	/*
 298	 * Since 440GR(x)/440EP(x) processors have the same pvr,
 299	 * we check the node path and set bit 28 in the cur_cpu_spec
 300	 * pvr for EP(x) processor version. This bit is always 0 in
 301	 * the "real" pvr. Then we call identify_cpu again with
 302	 * the new logical pvr to enable FPU support.
 303	 */
 304	if (model && strstr(model, "440EP")) {
 305		pvr = cur_cpu_spec->pvr_value | 0x8;
 306		identify_cpu(0, pvr);
 307		DBG("Using logical pvr %x for %s\n", pvr, model);
 308	}
 309}
 310#else
 311#define identical_pvr_fixup(node) do { } while(0)
 312#endif
 313
 314static void __init check_cpu_feature_properties(unsigned long node)
 315{
 316	int i;
 317	struct feature_property *fp = feature_properties;
 318	const __be32 *prop;
 319
 320	for (i = 0; i < (int)ARRAY_SIZE(feature_properties); ++i, ++fp) {
 321		prop = of_get_flat_dt_prop(node, fp->name, NULL);
 322		if (prop && be32_to_cpup(prop) >= fp->min_value) {
 323			cur_cpu_spec->cpu_features |= fp->cpu_feature;
 324			cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftr;
 325		}
 326	}
 327}
 328
 329static int __init early_init_dt_scan_cpus(unsigned long node,
 330					  const char *uname, int depth,
 331					  void *data)
 332{
 333	const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
 334	const __be32 *prop;
 335	const __be32 *intserv;
 336	int i, nthreads;
 337	int len;
 338	int found = -1;
 339	int found_thread = 0;
 340
 341	/* We are scanning "cpu" nodes only */
 342	if (type == NULL || strcmp(type, "cpu") != 0)
 343		return 0;
 344
 345	if (IS_ENABLED(CONFIG_PPC64))
 346		boot_cpu_node_count++;
 347
 348	/* Get physical cpuid */
 349	intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
 350	if (!intserv)
 351		intserv = of_get_flat_dt_prop(node, "reg", &len);
 352
 353	nthreads = len / sizeof(int);
 354
 355	/*
 356	 * Now see if any of these threads match our boot cpu.
 357	 * NOTE: This must match the parsing done in smp_setup_cpu_maps.
 358	 */
 359	for (i = 0; i < nthreads; i++) {
 360		if (be32_to_cpu(intserv[i]) ==
 361			fdt_boot_cpuid_phys(initial_boot_params)) {
 362			found = boot_cpu_count;
 363			found_thread = i;
 364		}
 365#ifdef CONFIG_SMP
 366		/* logical cpu id is always 0 on UP kernels */
 367		boot_cpu_count++;
 368#endif
 369	}
 370
 371	/* Not the boot CPU */
 372	if (found < 0)
 373		return 0;
 374
 
 
 375	boot_cpuid = found;
 376
 377	if (IS_ENABLED(CONFIG_PPC64))
 378		boot_cpu_hwid = be32_to_cpu(intserv[found_thread]);
 379
 380	if (nr_cpu_ids % nthreads != 0) {
 381		set_nr_cpu_ids(ALIGN(nr_cpu_ids, nthreads));
 382		pr_warn("nr_cpu_ids was not a multiple of threads_per_core, adjusted to %d\n",
 383			nr_cpu_ids);
 384	}
 385
 386	if (boot_cpuid >= nr_cpu_ids) {
 387		// Remember boot core for smp_setup_cpu_maps()
 388		boot_core_hwid = be32_to_cpu(intserv[0]);
 389
 390		pr_warn("Boot CPU %d (core hwid %d) >= nr_cpu_ids, adjusted boot CPU to %d\n",
 391			boot_cpuid, boot_core_hwid, found_thread);
 392
 393		// Adjust boot CPU to appear on logical core 0
 394		boot_cpuid = found_thread;
 395	}
 396
 397	DBG("boot cpu: logical %d physical %d\n", boot_cpuid,
 398	    be32_to_cpu(intserv[found_thread]));
 399
 400	/*
 401	 * PAPR defines "logical" PVR values for cpus that
 402	 * meet various levels of the architecture:
 403	 * 0x0f000001	Architecture version 2.04
 404	 * 0x0f000002	Architecture version 2.05
 405	 * If the cpu-version property in the cpu node contains
 406	 * such a value, we call identify_cpu again with the
 407	 * logical PVR value in order to use the cpu feature
 408	 * bits appropriate for the architecture level.
 409	 *
 410	 * A POWER6 partition in "POWER6 architected" mode
 411	 * uses the 0x0f000002 PVR value; in POWER5+ mode
 412	 * it uses 0x0f000001.
 413	 *
 414	 * If we're using device tree CPU feature discovery then we don't
 415	 * support the cpu-version property, and it's the responsibility of the
 416	 * firmware/hypervisor to provide the correct feature set for the
 417	 * architecture level via the ibm,powerpc-cpu-features binding.
 418	 */
 419	if (!dt_cpu_ftrs_in_use()) {
 420		prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
 421		if (prop && (be32_to_cpup(prop) & 0xff000000) == 0x0f000000) {
 422			identify_cpu(0, be32_to_cpup(prop));
 423			seq_buf_printf(&ppc_hw_desc, "0x%04x ", be32_to_cpup(prop));
 424		}
 425
 426		check_cpu_feature_properties(node);
 427		check_cpu_features(node, "ibm,pa-features", ibm_pa_features,
 428				   ARRAY_SIZE(ibm_pa_features));
 429		check_cpu_features(node, "ibm,pi-features", ibm_pi_features,
 430				   ARRAY_SIZE(ibm_pi_features));
 431	}
 432
 433	identical_pvr_fixup(node);
 434	init_mmu_slb_size(node);
 435
 436#ifdef CONFIG_PPC64
 437	if (nthreads == 1)
 438		cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
 439	else if (!dt_cpu_ftrs_in_use())
 440		cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
 
 441#endif
 
 442
 443	return 0;
 444}
 445
 446static int __init early_init_dt_scan_chosen_ppc(unsigned long node,
 447						const char *uname,
 448						int depth, void *data)
 449{
 450	const unsigned long *lprop; /* All these set by kernel, so no need to convert endian */
 451
 452	/* Use common scan routine to determine if this is the chosen node */
 453	if (early_init_dt_scan_chosen(data) < 0)
 454		return 0;
 455
 456#ifdef CONFIG_PPC64
 457	/* check if iommu is forced on or off */
 458	if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
 459		iommu_is_off = 1;
 460	if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
 461		iommu_force_on = 1;
 462#endif
 463
 464	/* mem=x on the command line is the preferred mechanism */
 465	lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
 466	if (lprop)
 467		memory_limit = *lprop;
 468
 469#ifdef CONFIG_PPC64
 470	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
 471	if (lprop)
 472		tce_alloc_start = *lprop;
 473	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
 474	if (lprop)
 475		tce_alloc_end = *lprop;
 476#endif
 477
 478#ifdef CONFIG_CRASH_RESERVE
 479	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
 480	if (lprop)
 481		crashk_res.start = *lprop;
 482
 483	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
 484	if (lprop)
 485		crashk_res.end = crashk_res.start + *lprop - 1;
 486#endif
 487
 488	/* break now */
 489	return 1;
 490}
 491
 492/*
 493 * Compare the range against max mem limit and update
 494 * size if it cross the limit.
 495 */
 496
 497#ifdef CONFIG_SPARSEMEM
 498static bool __init validate_mem_limit(u64 base, u64 *size)
 499{
 500	u64 max_mem = 1UL << (MAX_PHYSMEM_BITS);
 501
 502	if (base >= max_mem)
 503		return false;
 504	if ((base + *size) > max_mem)
 505		*size = max_mem - base;
 506	return true;
 507}
 508#else
 509static bool __init validate_mem_limit(u64 base, u64 *size)
 510{
 511	return true;
 512}
 513#endif
 514
 515#ifdef CONFIG_PPC_PSERIES
 516/*
 517 * Interpret the ibm dynamic reconfiguration memory LMBs.
 518 * This contains a list of memory blocks along with NUMA affinity
 519 * information.
 520 */
 521static int  __init early_init_drmem_lmb(struct drmem_lmb *lmb,
 522					const __be32 **usm,
 523					void *data)
 524{
 525	u64 base, size;
 526	int is_kexec_kdump = 0, rngs;
 527
 528	base = lmb->base_addr;
 529	size = drmem_lmb_size();
 530	rngs = 1;
 531
 532	/*
 533	 * Skip this block if the reserved bit is set in flags
 534	 * or if the block is not assigned to this partition.
 535	 */
 536	if ((lmb->flags & DRCONF_MEM_RESERVED) ||
 537	    !(lmb->flags & DRCONF_MEM_ASSIGNED))
 538		return 0;
 539
 540	if (*usm)
 541		is_kexec_kdump = 1;
 542
 543	if (is_kexec_kdump) {
 544		/*
 545		 * For each memblock in ibm,dynamic-memory, a
 546		 * corresponding entry in linux,drconf-usable-memory
 547		 * property contains a counter 'p' followed by 'p'
 548		 * (base, size) duple. Now read the counter from
 549		 * linux,drconf-usable-memory property
 550		 */
 551		rngs = dt_mem_next_cell(dt_root_size_cells, usm);
 552		if (!rngs) /* there are no (base, size) duple */
 553			return 0;
 554	}
 555
 556	do {
 557		if (is_kexec_kdump) {
 558			base = dt_mem_next_cell(dt_root_addr_cells, usm);
 559			size = dt_mem_next_cell(dt_root_size_cells, usm);
 560		}
 561
 562		if (iommu_is_off) {
 563			if (base >= 0x80000000ul)
 564				continue;
 565			if ((base + size) > 0x80000000ul)
 566				size = 0x80000000ul - base;
 567		}
 568
 569		if (!validate_mem_limit(base, &size))
 570			continue;
 571
 572		DBG("Adding: %llx -> %llx\n", base, size);
 573		memblock_add(base, size);
 574
 575		if (lmb->flags & DRCONF_MEM_HOTREMOVABLE)
 576			memblock_mark_hotplug(base, size);
 577	} while (--rngs);
 578
 579	return 0;
 580}
 581#endif /* CONFIG_PPC_PSERIES */
 582
 583static int __init early_init_dt_scan_memory_ppc(void)
 
 
 584{
 585#ifdef CONFIG_PPC_PSERIES
 586	const void *fdt = initial_boot_params;
 587	int node = fdt_path_offset(fdt, "/ibm,dynamic-reconfiguration-memory");
 588
 589	if (node > 0)
 590		walk_drmem_lmbs_early(node, NULL, early_init_drmem_lmb);
 591
 
 592#endif
 593
 594	return early_init_dt_scan_memory();
 595}
 596
 597/*
 598 * For a relocatable kernel, we need to get the memstart_addr first,
 599 * then use it to calculate the virtual kernel start address. This has
 600 * to happen at a very early stage (before machine_init). In this case,
 601 * we just want to get the memstart_address and would not like to mess the
 602 * memblock at this stage. So introduce a variable to skip the memblock_add()
 603 * for this reason.
 604 */
 605#ifdef CONFIG_RELOCATABLE
 606static int add_mem_to_memblock = 1;
 607#else
 608#define add_mem_to_memblock 1
 609#endif
 610
 611void __init early_init_dt_add_memory_arch(u64 base, u64 size)
 612{
 613#ifdef CONFIG_PPC64
 614	if (iommu_is_off) {
 615		if (base >= 0x80000000ul)
 616			return;
 617		if ((base + size) > 0x80000000ul)
 618			size = 0x80000000ul - base;
 619	}
 620#endif
 621	/* Keep track of the beginning of memory -and- the size of
 622	 * the very first block in the device-tree as it represents
 623	 * the RMA on ppc64 server
 624	 */
 625	if (base < memstart_addr) {
 626		memstart_addr = base;
 627		first_memblock_size = size;
 628	}
 629
 630	/* Add the chunk to the MEMBLOCK list */
 631	if (add_mem_to_memblock) {
 632		if (validate_mem_limit(base, &size))
 633			memblock_add(base, size);
 634	}
 635}
 636
 637static void __init early_reserve_mem_dt(void)
 638{
 639	unsigned long i, dt_root;
 640	int len;
 641	const __be32 *prop;
 642
 643	early_init_fdt_reserve_self();
 644	early_init_fdt_scan_reserved_mem();
 645
 646	dt_root = of_get_flat_dt_root();
 647
 648	prop = of_get_flat_dt_prop(dt_root, "reserved-ranges", &len);
 649
 650	if (!prop)
 651		return;
 652
 653	DBG("Found new-style reserved-ranges\n");
 654
 655	/* Each reserved range is an (address,size) pair, 2 cells each,
 656	 * totalling 4 cells per range. */
 657	for (i = 0; i < len / (sizeof(*prop) * 4); i++) {
 658		u64 base, size;
 659
 660		base = of_read_number(prop + (i * 4) + 0, 2);
 661		size = of_read_number(prop + (i * 4) + 2, 2);
 662
 663		if (size) {
 664			DBG("reserving: %llx -> %llx\n", base, size);
 665			memblock_reserve(base, size);
 666		}
 667	}
 668}
 669
 670static void __init early_reserve_mem(void)
 671{
 672	__be64 *reserve_map;
 673
 674	reserve_map = (__be64 *)(((unsigned long)initial_boot_params) +
 675			fdt_off_mem_rsvmap(initial_boot_params));
 676
 677	/* Look for the new "reserved-regions" property in the DT */
 678	early_reserve_mem_dt();
 679
 680#ifdef CONFIG_BLK_DEV_INITRD
 681	/* Then reserve the initrd, if any */
 682	if (initrd_start && (initrd_end > initrd_start)) {
 683		memblock_reserve(ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
 684			ALIGN(initrd_end, PAGE_SIZE) -
 685			ALIGN_DOWN(initrd_start, PAGE_SIZE));
 686	}
 687#endif /* CONFIG_BLK_DEV_INITRD */
 688
 689	if (!IS_ENABLED(CONFIG_PPC32))
 690		return;
 691
 692	/* 
 693	 * Handle the case where we might be booting from an old kexec
 694	 * image that setup the mem_rsvmap as pairs of 32-bit values
 695	 */
 696	if (be64_to_cpup(reserve_map) > 0xffffffffull) {
 697		u32 base_32, size_32;
 698		__be32 *reserve_map_32 = (__be32 *)reserve_map;
 699
 700		DBG("Found old 32-bit reserve map\n");
 701
 702		while (1) {
 703			base_32 = be32_to_cpup(reserve_map_32++);
 704			size_32 = be32_to_cpup(reserve_map_32++);
 705			if (size_32 == 0)
 706				break;
 707			DBG("reserving: %x -> %x\n", base_32, size_32);
 708			memblock_reserve(base_32, size_32);
 709		}
 710		return;
 711	}
 
 712}
 713
 714#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 715static bool tm_disabled __initdata;
 716
 717static int __init parse_ppc_tm(char *str)
 718{
 719	bool res;
 720
 721	if (kstrtobool(str, &res))
 722		return -EINVAL;
 723
 724	tm_disabled = !res;
 725
 726	return 0;
 727}
 728early_param("ppc_tm", parse_ppc_tm);
 729
 730static void __init tm_init(void)
 731{
 732	if (tm_disabled) {
 733		pr_info("Disabling hardware transactional memory (HTM)\n");
 734		cur_cpu_spec->cpu_user_features2 &=
 735			~(PPC_FEATURE2_HTM_NOSC | PPC_FEATURE2_HTM);
 736		cur_cpu_spec->cpu_features &= ~CPU_FTR_TM;
 737		return;
 738	}
 739
 740	pnv_tm_init();
 741}
 742#else
 743static void tm_init(void) { }
 744#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
 745
 746static int __init
 747early_init_dt_scan_model(unsigned long node, const char *uname,
 748			 int depth, void *data)
 749{
 750	const char *prop;
 751
 752	if (depth != 0)
 753		return 0;
 754
 755	prop = of_get_flat_dt_prop(node, "model", NULL);
 756	if (prop)
 757		seq_buf_printf(&ppc_hw_desc, "%s ", prop);
 758
 759	/* break now */
 760	return 1;
 761}
 762
 763#ifdef CONFIG_PPC64
 764static void __init save_fscr_to_task(void)
 765{
 766	/*
 767	 * Ensure the init_task (pid 0, aka swapper) uses the value of FSCR we
 768	 * have configured via the device tree features or via __init_FSCR().
 769	 * That value will then be propagated to pid 1 (init) and all future
 770	 * processes.
 771	 */
 772	if (early_cpu_has_feature(CPU_FTR_ARCH_207S))
 773		init_task.thread.fscr = mfspr(SPRN_FSCR);
 774}
 775#else
 776static inline void save_fscr_to_task(void) {}
 777#endif
 778
 779
 780void __init early_init_devtree(void *params)
 781{
 782	phys_addr_t limit;
 783
 784	DBG(" -> early_init_devtree(%px)\n", params);
 785
 786	/* Too early to BUG_ON(), do it by hand */
 787	if (!early_init_dt_verify(params))
 788		panic("BUG: Failed verifying flat device tree, bad version?");
 789
 790	of_scan_flat_dt(early_init_dt_scan_model, NULL);
 791
 792#ifdef CONFIG_PPC_RTAS
 793	/* Some machines might need RTAS info for debugging, grab it now. */
 794	of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
 795#endif
 796
 797#ifdef CONFIG_PPC_POWERNV
 798	/* Some machines might need OPAL info for debugging, grab it now. */
 799	of_scan_flat_dt(early_init_dt_scan_opal, NULL);
 800
 801	/* Scan tree for ultravisor feature */
 802	of_scan_flat_dt(early_init_dt_scan_ultravisor, NULL);
 803#endif
 804
 805#if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)
 806	/* scan tree to see if dump is active during last boot */
 807	of_scan_flat_dt(early_init_dt_scan_fw_dump, NULL);
 808#endif
 809
 810	/* Retrieve various informations from the /chosen node of the
 811	 * device-tree, including the platform type, initrd location and
 812	 * size, TCE reserve, and more ...
 813	 */
 814	of_scan_flat_dt(early_init_dt_scan_chosen_ppc, boot_command_line);
 815
 816	/* Scan memory nodes and rebuild MEMBLOCKs */
 817	early_init_dt_scan_root();
 818	early_init_dt_scan_memory_ppc();
 819
 820	/*
 821	 * As generic code authors expect to be able to use static keys
 822	 * in early_param() handlers, we initialize the static keys just
 823	 * before parsing early params (it's fine to call jump_label_init()
 824	 * more than once).
 825	 */
 826	jump_label_init();
 827	parse_early_param();
 828
 829	/* make sure we've parsed cmdline for mem= before this */
 830	if (memory_limit)
 831		first_memblock_size = min_t(u64, first_memblock_size, memory_limit);
 832	setup_initial_memory_limit(memstart_addr, first_memblock_size);
 833	/* Reserve MEMBLOCK regions used by kernel, initrd, dt, etc... */
 834	memblock_reserve(PHYSICAL_START, __pa(_end) - PHYSICAL_START);
 835	/* If relocatable, reserve first 32k for interrupt vectors etc. */
 836	if (PHYSICAL_START > MEMORY_START)
 837		memblock_reserve(MEMORY_START, 0x8000);
 838	reserve_kdump_trampoline();
 839#if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)
 840	/*
 841	 * If we fail to reserve memory for firmware-assisted dump then
 842	 * fallback to kexec based kdump.
 843	 */
 844	if (fadump_reserve_mem() == 0)
 845#endif
 846		reserve_crashkernel();
 847	early_reserve_mem();
 848
 849	/* Ensure that total memory size is page-aligned. */
 850	limit = ALIGN(memory_limit ?: memblock_phys_mem_size(), PAGE_SIZE);
 851	memblock_enforce_memory_limit(limit);
 852
 853#if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_PPC_4K_PAGES)
 854	if (!early_radix_enabled())
 855		memblock_cap_memory_range(0, 1UL << (H_MAX_PHYSMEM_BITS));
 856#endif
 857
 858	memblock_allow_resize();
 859	memblock_dump_all();
 860
 861	DBG("Phys. mem: %llx\n", (unsigned long long)memblock_phys_mem_size());
 862
 863	/* We may need to relocate the flat tree, do it now.
 864	 * FIXME .. and the initrd too? */
 865	move_device_tree();
 866
 
 
 867	DBG("Scanning CPUs ...\n");
 868
 869	dt_cpu_ftrs_scan();
 870
 871	// We can now add the CPU name & PVR to the hardware description
 872	seq_buf_printf(&ppc_hw_desc, "%s 0x%04lx ", cur_cpu_spec->cpu_name, mfspr(SPRN_PVR));
 873
 874	/* Retrieve CPU related informations from the flat tree
 875	 * (altivec support, boot CPU ID, ...)
 876	 */
 877	of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
 878	if (boot_cpuid < 0) {
 879		printk("Failed to identify boot CPU !\n");
 880		BUG();
 881	}
 882
 883	save_fscr_to_task();
 884
 885#if defined(CONFIG_SMP) && defined(CONFIG_PPC64)
 886	/* We'll later wait for secondaries to check in; there are
 887	 * NCPUS-1 non-boot CPUs  :-)
 888	 */
 889	spinning_secondaries = boot_cpu_count - 1;
 890#endif
 891
 892	mmu_early_init_devtree();
 893
 894#ifdef CONFIG_PPC_POWERNV
 895	/* Scan and build the list of machine check recoverable ranges */
 896	of_scan_flat_dt(early_init_dt_scan_recoverable_ranges, NULL);
 897#endif
 898	epapr_paravirt_early_init();
 899
 900	/* Now try to figure out if we are running on LPAR and so on */
 901	pseries_probe_fw_features();
 902
 903	/*
 904	 * Initialize pkey features and default AMR/IAMR values
 905	 */
 906	pkey_early_init_devtree();
 907
 908#ifdef CONFIG_PPC_PS3
 909	/* Identify PS3 firmware */
 910	if (of_flat_dt_is_compatible(of_get_flat_dt_root(), "sony,ps3"))
 911		powerpc_firmware_features |= FW_FEATURE_PS3_POSSIBLE;
 912#endif
 913
 914	/* If kexec left a PLPKS password in the DT, get it and clear it */
 915	plpks_early_init_devtree();
 916
 917	tm_init();
 918
 919	DBG(" <- early_init_devtree()\n");
 920}
 921
 922#ifdef CONFIG_RELOCATABLE
 923/*
 924 * This function run before early_init_devtree, so we have to init
 925 * initial_boot_params.
 926 */
 927void __init early_get_first_memblock_info(void *params, phys_addr_t *size)
 928{
 929	/* Setup flat device-tree pointer */
 930	initial_boot_params = params;
 931
 932	/*
 933	 * Scan the memory nodes and set add_mem_to_memblock to 0 to avoid
 934	 * mess the memblock.
 935	 */
 936	add_mem_to_memblock = 0;
 937	early_init_dt_scan_root();
 938	early_init_dt_scan_memory_ppc();
 939	add_mem_to_memblock = 1;
 940
 941	if (size)
 942		*size = first_memblock_size;
 943}
 944#endif
 945
 946/*******
 947 *
 948 * New implementation of the OF "find" APIs, return a refcounted
 949 * object, call of_node_put() when done.  The device tree and list
 950 * are protected by a rw_lock.
 951 *
 952 * Note that property management will need some locking as well,
 953 * this isn't dealt with yet.
 954 *
 955 *******/
 956
 957/**
 958 * of_get_ibm_chip_id - Returns the IBM "chip-id" of a device
 959 * @np: device node of the device
 960 *
 961 * This looks for a property "ibm,chip-id" in the node or any
 962 * of its parents and returns its content, or -1 if it cannot
 963 * be found.
 964 */
 965int of_get_ibm_chip_id(struct device_node *np)
 966{
 967	of_node_get(np);
 968	while (np) {
 969		u32 chip_id;
 970
 971		/*
 972		 * Skiboot may produce memory nodes that contain more than one
 973		 * cell in chip-id, we only read the first one here.
 974		 */
 975		if (!of_property_read_u32(np, "ibm,chip-id", &chip_id)) {
 976			of_node_put(np);
 977			return chip_id;
 978		}
 979
 980		np = of_get_next_parent(np);
 981	}
 982	return -1;
 983}
 984EXPORT_SYMBOL(of_get_ibm_chip_id);
 985
 986/**
 987 * cpu_to_chip_id - Return the cpus chip-id
 988 * @cpu: The logical cpu number.
 989 *
 990 * Return the value of the ibm,chip-id property corresponding to the given
 991 * logical cpu number. If the chip-id can not be found, returns -1.
 992 */
 993int cpu_to_chip_id(int cpu)
 994{
 995	struct device_node *np;
 996	int ret = -1, idx;
 997
 998	idx = cpu / threads_per_core;
 999	if (chip_id_lookup_table && chip_id_lookup_table[idx] != -1)
1000		return chip_id_lookup_table[idx];
1001
1002	np = of_get_cpu_node(cpu, NULL);
1003	if (np) {
1004		ret = of_get_ibm_chip_id(np);
1005		of_node_put(np);
1006
1007		if (chip_id_lookup_table)
1008			chip_id_lookup_table[idx] = ret;
1009	}
1010
1011	return ret;
 
1012}
1013EXPORT_SYMBOL(cpu_to_chip_id);
1014
1015bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
1016{
1017#ifdef CONFIG_SMP
1018	/*
1019	 * Early firmware scanning must use this rather than
1020	 * get_hard_smp_processor_id because we don't have pacas allocated
1021	 * until memory topology is discovered.
1022	 */
1023	if (cpu_to_phys_id != NULL)
1024		return (int)phys_id == cpu_to_phys_id[cpu];
1025#endif
1026
1027	return (int)phys_id == get_hard_smp_processor_id(cpu);
1028}