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v5.14.15
  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
 68int *chip_id_lookup_table;
 69
 70#ifdef CONFIG_PPC64
 71int __initdata iommu_is_off;
 72int __initdata iommu_force_on;
 73unsigned long tce_alloc_start, tce_alloc_end;
 74u64 ppc64_rma_size;
 
 75#endif
 76static phys_addr_t first_memblock_size;
 77static int __initdata boot_cpu_count;
 78
 79static int __init early_parse_mem(char *p)
 80{
 81	if (!p)
 82		return 1;
 83
 84	memory_limit = PAGE_ALIGN(memparse(p, &p));
 85	DBG("memory limit = 0x%llx\n", memory_limit);
 86
 87	return 0;
 88}
 89early_param("mem", early_parse_mem);
 90
 91/*
 92 * overlaps_initrd - check for overlap with page aligned extension of
 93 * initrd.
 94 */
 95static inline int overlaps_initrd(unsigned long start, unsigned long size)
 96{
 97#ifdef CONFIG_BLK_DEV_INITRD
 98	if (!initrd_start)
 99		return 0;
100
101	return	(start + size) > ALIGN_DOWN(initrd_start, PAGE_SIZE) &&
102			start <= ALIGN(initrd_end, PAGE_SIZE);
103#else
104	return 0;
105#endif
106}
107
108/**
109 * move_device_tree - move tree to an unused area, if needed.
110 *
111 * The device tree may be allocated beyond our memory limit, or inside the
112 * crash kernel region for kdump, or within the page aligned range of initrd.
113 * If so, move it out of the way.
114 */
115static void __init move_device_tree(void)
116{
117	unsigned long start, size;
118	void *p;
119
120	DBG("-> move_device_tree\n");
121
122	start = __pa(initial_boot_params);
123	size = fdt_totalsize(initial_boot_params);
124
125	if ((memory_limit && (start + size) > PHYSICAL_START + memory_limit) ||
126	    !memblock_is_memory(start + size - 1) ||
127	    overlaps_crashkernel(start, size) || overlaps_initrd(start, size)) {
128		p = memblock_alloc_raw(size, PAGE_SIZE);
129		if (!p)
130			panic("Failed to allocate %lu bytes to move device tree\n",
131			      size);
132		memcpy(p, initial_boot_params, size);
133		initial_boot_params = p;
134		DBG("Moved device tree to 0x%px\n", p);
135	}
136
137	DBG("<- move_device_tree\n");
138}
139
140/*
141 * ibm,pa-features is a per-cpu property that contains a string of
142 * attribute descriptors, each of which has a 2 byte header plus up
143 * to 254 bytes worth of processor attribute bits.  First header
144 * byte specifies the number of bytes following the header.
145 * Second header byte is an "attribute-specifier" type, of which
146 * zero is the only currently-defined value.
147 * Implementation:  Pass in the byte and bit offset for the feature
148 * that we are interested in.  The function will return -1 if the
149 * pa-features property is missing, or a 1/0 to indicate if the feature
150 * is supported/not supported.  Note that the bit numbers are
151 * big-endian to match the definition in PAPR.
 
 
 
152 */
153static struct ibm_pa_feature {
154	unsigned long	cpu_features;	/* CPU_FTR_xxx bit */
155	unsigned long	mmu_features;	/* MMU_FTR_xxx bit */
156	unsigned int	cpu_user_ftrs;	/* PPC_FEATURE_xxx bit */
157	unsigned int	cpu_user_ftrs2;	/* PPC_FEATURE2_xxx bit */
158	unsigned char	pabyte;		/* byte number in ibm,pa-features */
159	unsigned char	pabit;		/* bit number (big-endian) */
160	unsigned char	invert;		/* if 1, pa bit set => clear feature */
161} ibm_pa_features[] __initdata = {
 
 
162	{ .pabyte = 0,  .pabit = 0, .cpu_user_ftrs = PPC_FEATURE_HAS_MMU },
163	{ .pabyte = 0,  .pabit = 1, .cpu_user_ftrs = PPC_FEATURE_HAS_FPU },
164	{ .pabyte = 0,  .pabit = 3, .cpu_features  = CPU_FTR_CTRL },
165	{ .pabyte = 0,  .pabit = 6, .cpu_features  = CPU_FTR_NOEXECUTE },
166	{ .pabyte = 1,  .pabit = 2, .mmu_features  = MMU_FTR_CI_LARGE_PAGE },
167#ifdef CONFIG_PPC_RADIX_MMU
168	{ .pabyte = 40, .pabit = 0, .mmu_features  = MMU_FTR_TYPE_RADIX | MMU_FTR_GTSE },
169#endif
170	{ .pabyte = 5,  .pabit = 0, .cpu_features  = CPU_FTR_REAL_LE,
171				    .cpu_user_ftrs = PPC_FEATURE_TRUE_LE },
172	/*
173	 * If the kernel doesn't support TM (ie CONFIG_PPC_TRANSACTIONAL_MEM=n),
174	 * we don't want to turn on TM here, so we use the *_COMP versions
175	 * which are 0 if the kernel doesn't support TM.
176	 */
177	{ .pabyte = 22, .pabit = 0, .cpu_features = CPU_FTR_TM_COMP,
178	  .cpu_user_ftrs2 = PPC_FEATURE2_HTM_COMP | PPC_FEATURE2_HTM_NOSC_COMP },
179
180	{ .pabyte = 64, .pabit = 0, .cpu_features = CPU_FTR_DAWR1 },
 
 
 
 
 
 
 
 
 
 
 
 
181};
182
183static void __init scan_features(unsigned long node, const unsigned char *ftrs,
184				 unsigned long tablelen,
185				 struct ibm_pa_feature *fp,
186				 unsigned long ft_size)
187{
188	unsigned long i, len, bit;
189
190	/* find descriptor with type == 0 */
191	for (;;) {
192		if (tablelen < 3)
193			return;
194		len = 2 + ftrs[0];
195		if (tablelen < len)
196			return;		/* descriptor 0 not found */
197		if (ftrs[1] == 0)
198			break;
199		tablelen -= len;
200		ftrs += len;
201	}
202
203	/* loop over bits we know about */
204	for (i = 0; i < ft_size; ++i, ++fp) {
205		if (fp->pabyte >= ftrs[0])
206			continue;
207		bit = (ftrs[2 + fp->pabyte] >> (7 - fp->pabit)) & 1;
208		if (bit ^ fp->invert) {
209			cur_cpu_spec->cpu_features |= fp->cpu_features;
210			cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftrs;
211			cur_cpu_spec->cpu_user_features2 |= fp->cpu_user_ftrs2;
212			cur_cpu_spec->mmu_features |= fp->mmu_features;
213		} else {
214			cur_cpu_spec->cpu_features &= ~fp->cpu_features;
215			cur_cpu_spec->cpu_user_features &= ~fp->cpu_user_ftrs;
216			cur_cpu_spec->cpu_user_features2 &= ~fp->cpu_user_ftrs2;
217			cur_cpu_spec->mmu_features &= ~fp->mmu_features;
218		}
219	}
220}
221
222static void __init check_cpu_pa_features(unsigned long node)
 
 
223{
224	const unsigned char *pa_ftrs;
225	int tablelen;
226
227	pa_ftrs = of_get_flat_dt_prop(node, "ibm,pa-features", &tablelen);
228	if (pa_ftrs == NULL)
229		return;
230
231	scan_features(node, pa_ftrs, tablelen,
232		      ibm_pa_features, ARRAY_SIZE(ibm_pa_features));
233}
234
235#ifdef CONFIG_PPC_BOOK3S_64
236static void __init init_mmu_slb_size(unsigned long node)
237{
238	const __be32 *slb_size_ptr;
239
240	slb_size_ptr = of_get_flat_dt_prop(node, "slb-size", NULL) ? :
241			of_get_flat_dt_prop(node, "ibm,slb-size", NULL);
242
243	if (slb_size_ptr)
244		mmu_slb_size = be32_to_cpup(slb_size_ptr);
245}
246#else
247#define init_mmu_slb_size(node) do { } while(0)
248#endif
249
250static struct feature_property {
251	const char *name;
252	u32 min_value;
253	unsigned long cpu_feature;
254	unsigned long cpu_user_ftr;
255} feature_properties[] __initdata = {
256#ifdef CONFIG_ALTIVEC
257	{"altivec", 0, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
258	{"ibm,vmx", 1, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
259#endif /* CONFIG_ALTIVEC */
260#ifdef CONFIG_VSX
261	/* Yes, this _really_ is ibm,vmx == 2 to enable VSX */
262	{"ibm,vmx", 2, CPU_FTR_VSX, PPC_FEATURE_HAS_VSX},
263#endif /* CONFIG_VSX */
264#ifdef CONFIG_PPC64
265	{"ibm,dfp", 1, 0, PPC_FEATURE_HAS_DFP},
266	{"ibm,purr", 1, CPU_FTR_PURR, 0},
267	{"ibm,spurr", 1, CPU_FTR_SPURR, 0},
268#endif /* CONFIG_PPC64 */
269};
270
271#if defined(CONFIG_44x) && defined(CONFIG_PPC_FPU)
272static __init void identical_pvr_fixup(unsigned long node)
273{
274	unsigned int pvr;
275	const char *model = of_get_flat_dt_prop(node, "model", NULL);
276
277	/*
278	 * Since 440GR(x)/440EP(x) processors have the same pvr,
279	 * we check the node path and set bit 28 in the cur_cpu_spec
280	 * pvr for EP(x) processor version. This bit is always 0 in
281	 * the "real" pvr. Then we call identify_cpu again with
282	 * the new logical pvr to enable FPU support.
283	 */
284	if (model && strstr(model, "440EP")) {
285		pvr = cur_cpu_spec->pvr_value | 0x8;
286		identify_cpu(0, pvr);
287		DBG("Using logical pvr %x for %s\n", pvr, model);
288	}
289}
290#else
291#define identical_pvr_fixup(node) do { } while(0)
292#endif
293
294static void __init check_cpu_feature_properties(unsigned long node)
295{
296	int i;
297	struct feature_property *fp = feature_properties;
298	const __be32 *prop;
299
300	for (i = 0; i < (int)ARRAY_SIZE(feature_properties); ++i, ++fp) {
301		prop = of_get_flat_dt_prop(node, fp->name, NULL);
302		if (prop && be32_to_cpup(prop) >= fp->min_value) {
303			cur_cpu_spec->cpu_features |= fp->cpu_feature;
304			cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftr;
305		}
306	}
307}
308
309static int __init early_init_dt_scan_cpus(unsigned long node,
310					  const char *uname, int depth,
311					  void *data)
312{
313	const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
 
314	const __be32 *prop;
315	const __be32 *intserv;
316	int i, nthreads;
317	int len;
318	int found = -1;
319	int found_thread = 0;
320
321	/* We are scanning "cpu" nodes only */
322	if (type == NULL || strcmp(type, "cpu") != 0)
323		return 0;
324
 
 
 
325	/* Get physical cpuid */
326	intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
327	if (!intserv)
328		intserv = of_get_flat_dt_prop(node, "reg", &len);
329
330	nthreads = len / sizeof(int);
331
332	/*
333	 * Now see if any of these threads match our boot cpu.
334	 * NOTE: This must match the parsing done in smp_setup_cpu_maps.
335	 */
336	for (i = 0; i < nthreads; i++) {
337		if (be32_to_cpu(intserv[i]) ==
338			fdt_boot_cpuid_phys(initial_boot_params)) {
339			found = boot_cpu_count;
340			found_thread = i;
341		}
342#ifdef CONFIG_SMP
343		/* logical cpu id is always 0 on UP kernels */
344		boot_cpu_count++;
345#endif
346	}
347
348	/* Not the boot CPU */
349	if (found < 0)
350		return 0;
351
352	DBG("boot cpu: logical %d physical %d\n", found,
353	    be32_to_cpu(intserv[found_thread]));
354	boot_cpuid = found;
355
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
356	/*
357	 * PAPR defines "logical" PVR values for cpus that
358	 * meet various levels of the architecture:
359	 * 0x0f000001	Architecture version 2.04
360	 * 0x0f000002	Architecture version 2.05
361	 * If the cpu-version property in the cpu node contains
362	 * such a value, we call identify_cpu again with the
363	 * logical PVR value in order to use the cpu feature
364	 * bits appropriate for the architecture level.
365	 *
366	 * A POWER6 partition in "POWER6 architected" mode
367	 * uses the 0x0f000002 PVR value; in POWER5+ mode
368	 * it uses 0x0f000001.
369	 *
370	 * If we're using device tree CPU feature discovery then we don't
371	 * support the cpu-version property, and it's the responsibility of the
372	 * firmware/hypervisor to provide the correct feature set for the
373	 * architecture level via the ibm,powerpc-cpu-features binding.
374	 */
375	if (!dt_cpu_ftrs_in_use()) {
376		prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
377		if (prop && (be32_to_cpup(prop) & 0xff000000) == 0x0f000000)
378			identify_cpu(0, be32_to_cpup(prop));
 
 
379
380		check_cpu_feature_properties(node);
381		check_cpu_pa_features(node);
 
 
 
382	}
383
384	identical_pvr_fixup(node);
 
 
 
 
 
 
385	init_mmu_slb_size(node);
386
387#ifdef CONFIG_PPC64
388	if (nthreads == 1)
389		cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
390	else if (!dt_cpu_ftrs_in_use())
391		cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
392	allocate_paca(boot_cpuid);
393#endif
394	set_hard_smp_processor_id(found, be32_to_cpu(intserv[found_thread]));
395
396	return 0;
397}
398
399static int __init early_init_dt_scan_chosen_ppc(unsigned long node,
400						const char *uname,
401						int depth, void *data)
402{
403	const unsigned long *lprop; /* All these set by kernel, so no need to convert endian */
404
405	/* Use common scan routine to determine if this is the chosen node */
406	if (early_init_dt_scan_chosen(node, uname, depth, data) == 0)
407		return 0;
408
409#ifdef CONFIG_PPC64
410	/* check if iommu is forced on or off */
411	if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
412		iommu_is_off = 1;
413	if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
414		iommu_force_on = 1;
415#endif
416
417	/* mem=x on the command line is the preferred mechanism */
418	lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
419	if (lprop)
420		memory_limit = *lprop;
421
422#ifdef CONFIG_PPC64
423	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
424	if (lprop)
425		tce_alloc_start = *lprop;
426	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
427	if (lprop)
428		tce_alloc_end = *lprop;
429#endif
430
431#ifdef CONFIG_KEXEC_CORE
432	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
433	if (lprop)
434		crashk_res.start = *lprop;
435
436	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
437	if (lprop)
438		crashk_res.end = crashk_res.start + *lprop - 1;
439#endif
440
441	/* break now */
442	return 1;
443}
444
445/*
446 * Compare the range against max mem limit and update
447 * size if it cross the limit.
448 */
449
450#ifdef CONFIG_SPARSEMEM
451static bool validate_mem_limit(u64 base, u64 *size)
452{
453	u64 max_mem = 1UL << (MAX_PHYSMEM_BITS);
454
455	if (base >= max_mem)
456		return false;
457	if ((base + *size) > max_mem)
458		*size = max_mem - base;
459	return true;
460}
461#else
462static bool validate_mem_limit(u64 base, u64 *size)
463{
464	return true;
465}
466#endif
467
468#ifdef CONFIG_PPC_PSERIES
469/*
470 * Interpret the ibm dynamic reconfiguration memory LMBs.
471 * This contains a list of memory blocks along with NUMA affinity
472 * information.
473 */
474static int  __init early_init_drmem_lmb(struct drmem_lmb *lmb,
475					const __be32 **usm,
476					void *data)
477{
478	u64 base, size;
479	int is_kexec_kdump = 0, rngs;
480
481	base = lmb->base_addr;
482	size = drmem_lmb_size();
483	rngs = 1;
484
485	/*
486	 * Skip this block if the reserved bit is set in flags
487	 * or if the block is not assigned to this partition.
488	 */
489	if ((lmb->flags & DRCONF_MEM_RESERVED) ||
490	    !(lmb->flags & DRCONF_MEM_ASSIGNED))
491		return 0;
492
493	if (*usm)
494		is_kexec_kdump = 1;
495
496	if (is_kexec_kdump) {
497		/*
498		 * For each memblock in ibm,dynamic-memory, a
499		 * corresponding entry in linux,drconf-usable-memory
500		 * property contains a counter 'p' followed by 'p'
501		 * (base, size) duple. Now read the counter from
502		 * linux,drconf-usable-memory property
503		 */
504		rngs = dt_mem_next_cell(dt_root_size_cells, usm);
505		if (!rngs) /* there are no (base, size) duple */
506			return 0;
507	}
508
509	do {
510		if (is_kexec_kdump) {
511			base = dt_mem_next_cell(dt_root_addr_cells, usm);
512			size = dt_mem_next_cell(dt_root_size_cells, usm);
513		}
514
515		if (iommu_is_off) {
516			if (base >= 0x80000000ul)
517				continue;
518			if ((base + size) > 0x80000000ul)
519				size = 0x80000000ul - base;
520		}
521
522		if (!validate_mem_limit(base, &size))
523			continue;
524
525		DBG("Adding: %llx -> %llx\n", base, size);
526		memblock_add(base, size);
527
528		if (lmb->flags & DRCONF_MEM_HOTREMOVABLE)
529			memblock_mark_hotplug(base, size);
530	} while (--rngs);
531
532	return 0;
533}
534#endif /* CONFIG_PPC_PSERIES */
535
536static int __init early_init_dt_scan_memory_ppc(unsigned long node,
537						const char *uname,
538						int depth, void *data)
539{
540#ifdef CONFIG_PPC_PSERIES
541	if (depth == 1 &&
542	    strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0) {
 
 
543		walk_drmem_lmbs_early(node, NULL, early_init_drmem_lmb);
544		return 0;
545	}
546#endif
547	
548	return early_init_dt_scan_memory(node, uname, depth, data);
549}
550
551/*
552 * For a relocatable kernel, we need to get the memstart_addr first,
553 * then use it to calculate the virtual kernel start address. This has
554 * to happen at a very early stage (before machine_init). In this case,
555 * we just want to get the memstart_address and would not like to mess the
556 * memblock at this stage. So introduce a variable to skip the memblock_add()
557 * for this reason.
558 */
559#ifdef CONFIG_RELOCATABLE
560static int add_mem_to_memblock = 1;
561#else
562#define add_mem_to_memblock 1
563#endif
564
565void __init early_init_dt_add_memory_arch(u64 base, u64 size)
566{
567#ifdef CONFIG_PPC64
568	if (iommu_is_off) {
569		if (base >= 0x80000000ul)
570			return;
571		if ((base + size) > 0x80000000ul)
572			size = 0x80000000ul - base;
573	}
574#endif
575	/* Keep track of the beginning of memory -and- the size of
576	 * the very first block in the device-tree as it represents
577	 * the RMA on ppc64 server
578	 */
579	if (base < memstart_addr) {
580		memstart_addr = base;
581		first_memblock_size = size;
582	}
583
584	/* Add the chunk to the MEMBLOCK list */
585	if (add_mem_to_memblock) {
586		if (validate_mem_limit(base, &size))
587			memblock_add(base, size);
588	}
589}
590
591static void __init early_reserve_mem_dt(void)
592{
593	unsigned long i, dt_root;
594	int len;
595	const __be32 *prop;
596
597	early_init_fdt_reserve_self();
598	early_init_fdt_scan_reserved_mem();
599
600	dt_root = of_get_flat_dt_root();
601
602	prop = of_get_flat_dt_prop(dt_root, "reserved-ranges", &len);
603
604	if (!prop)
605		return;
606
607	DBG("Found new-style reserved-ranges\n");
608
609	/* Each reserved range is an (address,size) pair, 2 cells each,
610	 * totalling 4 cells per range. */
611	for (i = 0; i < len / (sizeof(*prop) * 4); i++) {
612		u64 base, size;
613
614		base = of_read_number(prop + (i * 4) + 0, 2);
615		size = of_read_number(prop + (i * 4) + 2, 2);
616
617		if (size) {
618			DBG("reserving: %llx -> %llx\n", base, size);
619			memblock_reserve(base, size);
620		}
621	}
622}
623
624static void __init early_reserve_mem(void)
625{
626	__be64 *reserve_map;
627
628	reserve_map = (__be64 *)(((unsigned long)initial_boot_params) +
629			fdt_off_mem_rsvmap(initial_boot_params));
630
631	/* Look for the new "reserved-regions" property in the DT */
632	early_reserve_mem_dt();
633
634#ifdef CONFIG_BLK_DEV_INITRD
635	/* Then reserve the initrd, if any */
636	if (initrd_start && (initrd_end > initrd_start)) {
637		memblock_reserve(ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
638			ALIGN(initrd_end, PAGE_SIZE) -
639			ALIGN_DOWN(initrd_start, PAGE_SIZE));
640	}
641#endif /* CONFIG_BLK_DEV_INITRD */
642
643#ifdef CONFIG_PPC32
 
 
644	/* 
645	 * Handle the case where we might be booting from an old kexec
646	 * image that setup the mem_rsvmap as pairs of 32-bit values
647	 */
648	if (be64_to_cpup(reserve_map) > 0xffffffffull) {
649		u32 base_32, size_32;
650		__be32 *reserve_map_32 = (__be32 *)reserve_map;
651
652		DBG("Found old 32-bit reserve map\n");
653
654		while (1) {
655			base_32 = be32_to_cpup(reserve_map_32++);
656			size_32 = be32_to_cpup(reserve_map_32++);
657			if (size_32 == 0)
658				break;
659			DBG("reserving: %x -> %x\n", base_32, size_32);
660			memblock_reserve(base_32, size_32);
661		}
662		return;
663	}
664#endif
665}
666
667#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
668static bool tm_disabled __initdata;
669
670static int __init parse_ppc_tm(char *str)
671{
672	bool res;
673
674	if (kstrtobool(str, &res))
675		return -EINVAL;
676
677	tm_disabled = !res;
678
679	return 0;
680}
681early_param("ppc_tm", parse_ppc_tm);
682
683static void __init tm_init(void)
684{
685	if (tm_disabled) {
686		pr_info("Disabling hardware transactional memory (HTM)\n");
687		cur_cpu_spec->cpu_user_features2 &=
688			~(PPC_FEATURE2_HTM_NOSC | PPC_FEATURE2_HTM);
689		cur_cpu_spec->cpu_features &= ~CPU_FTR_TM;
690		return;
691	}
692
693	pnv_tm_init();
694}
695#else
696static void tm_init(void) { }
697#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
698
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
699#ifdef CONFIG_PPC64
700static void __init save_fscr_to_task(void)
701{
702	/*
703	 * Ensure the init_task (pid 0, aka swapper) uses the value of FSCR we
704	 * have configured via the device tree features or via __init_FSCR().
705	 * That value will then be propagated to pid 1 (init) and all future
706	 * processes.
707	 */
708	if (early_cpu_has_feature(CPU_FTR_ARCH_207S))
709		init_task.thread.fscr = mfspr(SPRN_FSCR);
710}
711#else
712static inline void save_fscr_to_task(void) {}
713#endif
714
715
716void __init early_init_devtree(void *params)
717{
718	phys_addr_t limit;
719
720	DBG(" -> early_init_devtree(%px)\n", params);
721
722	/* Too early to BUG_ON(), do it by hand */
723	if (!early_init_dt_verify(params))
724		panic("BUG: Failed verifying flat device tree, bad version?");
725
 
 
726#ifdef CONFIG_PPC_RTAS
727	/* Some machines might need RTAS info for debugging, grab it now. */
728	of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
729#endif
730
731#ifdef CONFIG_PPC_POWERNV
732	/* Some machines might need OPAL info for debugging, grab it now. */
733	of_scan_flat_dt(early_init_dt_scan_opal, NULL);
734
735	/* Scan tree for ultravisor feature */
736	of_scan_flat_dt(early_init_dt_scan_ultravisor, NULL);
737#endif
738
739#if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)
740	/* scan tree to see if dump is active during last boot */
741	of_scan_flat_dt(early_init_dt_scan_fw_dump, NULL);
742#endif
743
744	/* Retrieve various informations from the /chosen node of the
745	 * device-tree, including the platform type, initrd location and
746	 * size, TCE reserve, and more ...
747	 */
748	of_scan_flat_dt(early_init_dt_scan_chosen_ppc, boot_command_line);
749
 
 
 
750	/* Scan memory nodes and rebuild MEMBLOCKs */
751	of_scan_flat_dt(early_init_dt_scan_root, NULL);
752	of_scan_flat_dt(early_init_dt_scan_memory_ppc, NULL);
753
 
 
 
 
 
 
 
754	parse_early_param();
755
756	/* make sure we've parsed cmdline for mem= before this */
757	if (memory_limit)
758		first_memblock_size = min_t(u64, first_memblock_size, memory_limit);
759	setup_initial_memory_limit(memstart_addr, first_memblock_size);
760	/* Reserve MEMBLOCK regions used by kernel, initrd, dt, etc... */
761	memblock_reserve(PHYSICAL_START, __pa(_end) - PHYSICAL_START);
 
 
 
 
 
762	/* If relocatable, reserve first 32k for interrupt vectors etc. */
 
 
763	if (PHYSICAL_START > MEMORY_START)
764		memblock_reserve(MEMORY_START, 0x8000);
765	reserve_kdump_trampoline();
766#if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)
767	/*
768	 * If we fail to reserve memory for firmware-assisted dump then
769	 * fallback to kexec based kdump.
770	 */
771	if (fadump_reserve_mem() == 0)
772#endif
773		reserve_crashkernel();
774	early_reserve_mem();
775
776	/* Ensure that total memory size is page-aligned. */
777	limit = ALIGN(memory_limit ?: memblock_phys_mem_size(), PAGE_SIZE);
778	memblock_enforce_memory_limit(limit);
 
 
 
779
780#if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_PPC_4K_PAGES)
781	if (!early_radix_enabled())
782		memblock_cap_memory_range(0, 1UL << (H_MAX_PHYSMEM_BITS));
783#endif
784
785	memblock_allow_resize();
786	memblock_dump_all();
787
788	DBG("Phys. mem: %llx\n", (unsigned long long)memblock_phys_mem_size());
789
790	/* We may need to relocate the flat tree, do it now.
791	 * FIXME .. and the initrd too? */
792	move_device_tree();
793
794	allocate_paca_ptrs();
795
796	DBG("Scanning CPUs ...\n");
797
798	dt_cpu_ftrs_scan();
799
800	/* Retrieve CPU related informations from the flat tree
801	 * (altivec support, boot CPU ID, ...)
802	 */
803	of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
804	if (boot_cpuid < 0) {
805		printk("Failed to identify boot CPU !\n");
806		BUG();
807	}
808
809	save_fscr_to_task();
810
811#if defined(CONFIG_SMP) && defined(CONFIG_PPC64)
812	/* We'll later wait for secondaries to check in; there are
813	 * NCPUS-1 non-boot CPUs  :-)
814	 */
815	spinning_secondaries = boot_cpu_count - 1;
816#endif
817
818	mmu_early_init_devtree();
819
 
 
 
820#ifdef CONFIG_PPC_POWERNV
821	/* Scan and build the list of machine check recoverable ranges */
822	of_scan_flat_dt(early_init_dt_scan_recoverable_ranges, NULL);
823#endif
824	epapr_paravirt_early_init();
825
826	/* Now try to figure out if we are running on LPAR and so on */
827	pseries_probe_fw_features();
828
829	/*
830	 * Initialize pkey features and default AMR/IAMR values
831	 */
832	pkey_early_init_devtree();
833
834#ifdef CONFIG_PPC_PS3
835	/* Identify PS3 firmware */
836	if (of_flat_dt_is_compatible(of_get_flat_dt_root(), "sony,ps3"))
837		powerpc_firmware_features |= FW_FEATURE_PS3_POSSIBLE;
838#endif
839
 
 
 
840	tm_init();
841
842	DBG(" <- early_init_devtree()\n");
843}
844
845#ifdef CONFIG_RELOCATABLE
846/*
847 * This function run before early_init_devtree, so we have to init
848 * initial_boot_params.
849 */
850void __init early_get_first_memblock_info(void *params, phys_addr_t *size)
851{
852	/* Setup flat device-tree pointer */
853	initial_boot_params = params;
854
855	/*
856	 * Scan the memory nodes and set add_mem_to_memblock to 0 to avoid
857	 * mess the memblock.
858	 */
859	add_mem_to_memblock = 0;
860	of_scan_flat_dt(early_init_dt_scan_root, NULL);
861	of_scan_flat_dt(early_init_dt_scan_memory_ppc, NULL);
862	add_mem_to_memblock = 1;
863
864	if (size)
865		*size = first_memblock_size;
866}
867#endif
868
869/*******
870 *
871 * New implementation of the OF "find" APIs, return a refcounted
872 * object, call of_node_put() when done.  The device tree and list
873 * are protected by a rw_lock.
874 *
875 * Note that property management will need some locking as well,
876 * this isn't dealt with yet.
877 *
878 *******/
879
880/**
881 * of_get_ibm_chip_id - Returns the IBM "chip-id" of a device
882 * @np: device node of the device
883 *
884 * This looks for a property "ibm,chip-id" in the node or any
885 * of its parents and returns its content, or -1 if it cannot
886 * be found.
887 */
888int of_get_ibm_chip_id(struct device_node *np)
889{
890	of_node_get(np);
891	while (np) {
892		u32 chip_id;
893
894		/*
895		 * Skiboot may produce memory nodes that contain more than one
896		 * cell in chip-id, we only read the first one here.
897		 */
898		if (!of_property_read_u32(np, "ibm,chip-id", &chip_id)) {
899			of_node_put(np);
900			return chip_id;
901		}
902
903		np = of_get_next_parent(np);
904	}
905	return -1;
906}
907EXPORT_SYMBOL(of_get_ibm_chip_id);
908
909/**
910 * cpu_to_chip_id - Return the cpus chip-id
911 * @cpu: The logical cpu number.
912 *
913 * Return the value of the ibm,chip-id property corresponding to the given
914 * logical cpu number. If the chip-id can not be found, returns -1.
915 */
916int cpu_to_chip_id(int cpu)
917{
918	struct device_node *np;
919	int ret = -1, idx;
920
921	idx = cpu / threads_per_core;
922	if (chip_id_lookup_table && chip_id_lookup_table[idx] != -1)
923		return chip_id_lookup_table[idx];
924
925	np = of_get_cpu_node(cpu, NULL);
926	if (np) {
927		ret = of_get_ibm_chip_id(np);
928		of_node_put(np);
929
930		if (chip_id_lookup_table)
931			chip_id_lookup_table[idx] = ret;
932	}
933
934	return ret;
935}
936EXPORT_SYMBOL(cpu_to_chip_id);
937
938bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
939{
940#ifdef CONFIG_SMP
941	/*
942	 * Early firmware scanning must use this rather than
943	 * get_hard_smp_processor_id because we don't have pacas allocated
944	 * until memory topology is discovered.
945	 */
946	if (cpu_to_phys_id != NULL)
947		return (int)phys_id == cpu_to_phys_id[cpu];
948#endif
949
950	return (int)phys_id == get_hard_smp_processor_id(cpu);
951}
v6.13.7
   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 *cpu_version = NULL;
 335	const __be32 *prop;
 336	const __be32 *intserv;
 337	int i, nthreads;
 338	int len;
 339	int found = -1;
 340	int found_thread = 0;
 341
 342	/* We are scanning "cpu" nodes only */
 343	if (type == NULL || strcmp(type, "cpu") != 0)
 344		return 0;
 345
 346	if (IS_ENABLED(CONFIG_PPC64))
 347		boot_cpu_node_count++;
 348
 349	/* Get physical cpuid */
 350	intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
 351	if (!intserv)
 352		intserv = of_get_flat_dt_prop(node, "reg", &len);
 353
 354	nthreads = len / sizeof(int);
 355
 356	/*
 357	 * Now see if any of these threads match our boot cpu.
 358	 * NOTE: This must match the parsing done in smp_setup_cpu_maps.
 359	 */
 360	for (i = 0; i < nthreads; i++) {
 361		if (be32_to_cpu(intserv[i]) ==
 362			fdt_boot_cpuid_phys(initial_boot_params)) {
 363			found = boot_cpu_count;
 364			found_thread = i;
 365		}
 366#ifdef CONFIG_SMP
 367		/* logical cpu id is always 0 on UP kernels */
 368		boot_cpu_count++;
 369#endif
 370	}
 371
 372	/* Not the boot CPU */
 373	if (found < 0)
 374		return 0;
 375
 
 
 376	boot_cpuid = found;
 377
 378	if (IS_ENABLED(CONFIG_PPC64))
 379		boot_cpu_hwid = be32_to_cpu(intserv[found_thread]);
 380
 381	if (nr_cpu_ids % nthreads != 0) {
 382		set_nr_cpu_ids(ALIGN(nr_cpu_ids, nthreads));
 383		pr_warn("nr_cpu_ids was not a multiple of threads_per_core, adjusted to %d\n",
 384			nr_cpu_ids);
 385	}
 386
 387	if (boot_cpuid >= nr_cpu_ids) {
 388		// Remember boot core for smp_setup_cpu_maps()
 389		boot_core_hwid = be32_to_cpu(intserv[0]);
 390
 391		pr_warn("Boot CPU %d (core hwid %d) >= nr_cpu_ids, adjusted boot CPU to %d\n",
 392			boot_cpuid, boot_core_hwid, found_thread);
 393
 394		// Adjust boot CPU to appear on logical core 0
 395		boot_cpuid = found_thread;
 396	}
 397
 398	DBG("boot cpu: logical %d physical %d\n", boot_cpuid,
 399	    be32_to_cpu(intserv[found_thread]));
 400
 401	/*
 402	 * PAPR defines "logical" PVR values for cpus that
 403	 * meet various levels of the architecture:
 404	 * 0x0f000001	Architecture version 2.04
 405	 * 0x0f000002	Architecture version 2.05
 406	 * If the cpu-version property in the cpu node contains
 407	 * such a value, we call identify_cpu again with the
 408	 * logical PVR value in order to use the cpu feature
 409	 * bits appropriate for the architecture level.
 410	 *
 411	 * A POWER6 partition in "POWER6 architected" mode
 412	 * uses the 0x0f000002 PVR value; in POWER5+ mode
 413	 * it uses 0x0f000001.
 414	 *
 415	 * If we're using device tree CPU feature discovery then we don't
 416	 * support the cpu-version property, and it's the responsibility of the
 417	 * firmware/hypervisor to provide the correct feature set for the
 418	 * architecture level via the ibm,powerpc-cpu-features binding.
 419	 */
 420	if (!dt_cpu_ftrs_in_use()) {
 421		prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
 422		if (prop && (be32_to_cpup(prop) & 0xff000000) == 0x0f000000) {
 423			identify_cpu(0, be32_to_cpup(prop));
 424			cpu_version = prop;
 425		}
 426
 427		check_cpu_feature_properties(node);
 428		check_cpu_features(node, "ibm,pa-features", ibm_pa_features,
 429				   ARRAY_SIZE(ibm_pa_features));
 430		check_cpu_features(node, "ibm,pi-features", ibm_pi_features,
 431				   ARRAY_SIZE(ibm_pi_features));
 432	}
 433
 434	identical_pvr_fixup(node);
 435
 436	// We can now add the CPU name & PVR to the hardware description
 437	seq_buf_printf(&ppc_hw_desc, "%s 0x%04lx ", cur_cpu_spec->cpu_name, mfspr(SPRN_PVR));
 438	if (cpu_version)
 439		seq_buf_printf(&ppc_hw_desc, "0x%04x ", be32_to_cpup(cpu_version));
 440
 441	init_mmu_slb_size(node);
 442
 443#ifdef CONFIG_PPC64
 444	if (nthreads == 1)
 445		cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
 446	else if (!dt_cpu_ftrs_in_use())
 447		cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
 
 448#endif
 
 449
 450	return 0;
 451}
 452
 453static int __init early_init_dt_scan_chosen_ppc(unsigned long node,
 454						const char *uname,
 455						int depth, void *data)
 456{
 457	const unsigned long *lprop; /* All these set by kernel, so no need to convert endian */
 458
 459	/* Use common scan routine to determine if this is the chosen node */
 460	if (early_init_dt_scan_chosen(data) < 0)
 461		return 0;
 462
 463#ifdef CONFIG_PPC64
 464	/* check if iommu is forced on or off */
 465	if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
 466		iommu_is_off = 1;
 467	if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
 468		iommu_force_on = 1;
 469#endif
 470
 471	/* mem=x on the command line is the preferred mechanism */
 472	lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
 473	if (lprop)
 474		memory_limit = *lprop;
 475
 476#ifdef CONFIG_PPC64
 477	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
 478	if (lprop)
 479		tce_alloc_start = *lprop;
 480	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
 481	if (lprop)
 482		tce_alloc_end = *lprop;
 483#endif
 484
 485#ifdef CONFIG_CRASH_RESERVE
 486	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
 487	if (lprop)
 488		crashk_res.start = *lprop;
 489
 490	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
 491	if (lprop)
 492		crashk_res.end = crashk_res.start + *lprop - 1;
 493#endif
 494
 495	/* break now */
 496	return 1;
 497}
 498
 499/*
 500 * Compare the range against max mem limit and update
 501 * size if it cross the limit.
 502 */
 503
 504#ifdef CONFIG_SPARSEMEM
 505static bool __init validate_mem_limit(u64 base, u64 *size)
 506{
 507	u64 max_mem = 1UL << (MAX_PHYSMEM_BITS);
 508
 509	if (base >= max_mem)
 510		return false;
 511	if ((base + *size) > max_mem)
 512		*size = max_mem - base;
 513	return true;
 514}
 515#else
 516static bool __init validate_mem_limit(u64 base, u64 *size)
 517{
 518	return true;
 519}
 520#endif
 521
 522#ifdef CONFIG_PPC_PSERIES
 523/*
 524 * Interpret the ibm dynamic reconfiguration memory LMBs.
 525 * This contains a list of memory blocks along with NUMA affinity
 526 * information.
 527 */
 528static int  __init early_init_drmem_lmb(struct drmem_lmb *lmb,
 529					const __be32 **usm,
 530					void *data)
 531{
 532	u64 base, size;
 533	int is_kexec_kdump = 0, rngs;
 534
 535	base = lmb->base_addr;
 536	size = drmem_lmb_size();
 537	rngs = 1;
 538
 539	/*
 540	 * Skip this block if the reserved bit is set in flags
 541	 * or if the block is not assigned to this partition.
 542	 */
 543	if ((lmb->flags & DRCONF_MEM_RESERVED) ||
 544	    !(lmb->flags & DRCONF_MEM_ASSIGNED))
 545		return 0;
 546
 547	if (*usm)
 548		is_kexec_kdump = 1;
 549
 550	if (is_kexec_kdump) {
 551		/*
 552		 * For each memblock in ibm,dynamic-memory, a
 553		 * corresponding entry in linux,drconf-usable-memory
 554		 * property contains a counter 'p' followed by 'p'
 555		 * (base, size) duple. Now read the counter from
 556		 * linux,drconf-usable-memory property
 557		 */
 558		rngs = dt_mem_next_cell(dt_root_size_cells, usm);
 559		if (!rngs) /* there are no (base, size) duple */
 560			return 0;
 561	}
 562
 563	do {
 564		if (is_kexec_kdump) {
 565			base = dt_mem_next_cell(dt_root_addr_cells, usm);
 566			size = dt_mem_next_cell(dt_root_size_cells, usm);
 567		}
 568
 569		if (iommu_is_off) {
 570			if (base >= 0x80000000ul)
 571				continue;
 572			if ((base + size) > 0x80000000ul)
 573				size = 0x80000000ul - base;
 574		}
 575
 576		if (!validate_mem_limit(base, &size))
 577			continue;
 578
 579		DBG("Adding: %llx -> %llx\n", base, size);
 580		memblock_add(base, size);
 581
 582		if (lmb->flags & DRCONF_MEM_HOTREMOVABLE)
 583			memblock_mark_hotplug(base, size);
 584	} while (--rngs);
 585
 586	return 0;
 587}
 588#endif /* CONFIG_PPC_PSERIES */
 589
 590static int __init early_init_dt_scan_memory_ppc(void)
 
 
 591{
 592#ifdef CONFIG_PPC_PSERIES
 593	const void *fdt = initial_boot_params;
 594	int node = fdt_path_offset(fdt, "/ibm,dynamic-reconfiguration-memory");
 595
 596	if (node > 0)
 597		walk_drmem_lmbs_early(node, NULL, early_init_drmem_lmb);
 598
 
 599#endif
 600
 601	return early_init_dt_scan_memory();
 602}
 603
 604/*
 605 * For a relocatable kernel, we need to get the memstart_addr first,
 606 * then use it to calculate the virtual kernel start address. This has
 607 * to happen at a very early stage (before machine_init). In this case,
 608 * we just want to get the memstart_address and would not like to mess the
 609 * memblock at this stage. So introduce a variable to skip the memblock_add()
 610 * for this reason.
 611 */
 612#ifdef CONFIG_RELOCATABLE
 613static int add_mem_to_memblock = 1;
 614#else
 615#define add_mem_to_memblock 1
 616#endif
 617
 618void __init early_init_dt_add_memory_arch(u64 base, u64 size)
 619{
 620#ifdef CONFIG_PPC64
 621	if (iommu_is_off) {
 622		if (base >= 0x80000000ul)
 623			return;
 624		if ((base + size) > 0x80000000ul)
 625			size = 0x80000000ul - base;
 626	}
 627#endif
 628	/* Keep track of the beginning of memory -and- the size of
 629	 * the very first block in the device-tree as it represents
 630	 * the RMA on ppc64 server
 631	 */
 632	if (base < memstart_addr) {
 633		memstart_addr = base;
 634		first_memblock_size = size;
 635	}
 636
 637	/* Add the chunk to the MEMBLOCK list */
 638	if (add_mem_to_memblock) {
 639		if (validate_mem_limit(base, &size))
 640			memblock_add(base, size);
 641	}
 642}
 643
 644static void __init early_reserve_mem_dt(void)
 645{
 646	unsigned long i, dt_root;
 647	int len;
 648	const __be32 *prop;
 649
 650	early_init_fdt_reserve_self();
 651	early_init_fdt_scan_reserved_mem();
 652
 653	dt_root = of_get_flat_dt_root();
 654
 655	prop = of_get_flat_dt_prop(dt_root, "reserved-ranges", &len);
 656
 657	if (!prop)
 658		return;
 659
 660	DBG("Found new-style reserved-ranges\n");
 661
 662	/* Each reserved range is an (address,size) pair, 2 cells each,
 663	 * totalling 4 cells per range. */
 664	for (i = 0; i < len / (sizeof(*prop) * 4); i++) {
 665		u64 base, size;
 666
 667		base = of_read_number(prop + (i * 4) + 0, 2);
 668		size = of_read_number(prop + (i * 4) + 2, 2);
 669
 670		if (size) {
 671			DBG("reserving: %llx -> %llx\n", base, size);
 672			memblock_reserve(base, size);
 673		}
 674	}
 675}
 676
 677static void __init early_reserve_mem(void)
 678{
 679	__be64 *reserve_map;
 680
 681	reserve_map = (__be64 *)(((unsigned long)initial_boot_params) +
 682			fdt_off_mem_rsvmap(initial_boot_params));
 683
 684	/* Look for the new "reserved-regions" property in the DT */
 685	early_reserve_mem_dt();
 686
 687#ifdef CONFIG_BLK_DEV_INITRD
 688	/* Then reserve the initrd, if any */
 689	if (initrd_start && (initrd_end > initrd_start)) {
 690		memblock_reserve(ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
 691			ALIGN(initrd_end, PAGE_SIZE) -
 692			ALIGN_DOWN(initrd_start, PAGE_SIZE));
 693	}
 694#endif /* CONFIG_BLK_DEV_INITRD */
 695
 696	if (!IS_ENABLED(CONFIG_PPC32))
 697		return;
 698
 699	/* 
 700	 * Handle the case where we might be booting from an old kexec
 701	 * image that setup the mem_rsvmap as pairs of 32-bit values
 702	 */
 703	if (be64_to_cpup(reserve_map) > 0xffffffffull) {
 704		u32 base_32, size_32;
 705		__be32 *reserve_map_32 = (__be32 *)reserve_map;
 706
 707		DBG("Found old 32-bit reserve map\n");
 708
 709		while (1) {
 710			base_32 = be32_to_cpup(reserve_map_32++);
 711			size_32 = be32_to_cpup(reserve_map_32++);
 712			if (size_32 == 0)
 713				break;
 714			DBG("reserving: %x -> %x\n", base_32, size_32);
 715			memblock_reserve(base_32, size_32);
 716		}
 717		return;
 718	}
 
 719}
 720
 721#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 722static bool tm_disabled __initdata;
 723
 724static int __init parse_ppc_tm(char *str)
 725{
 726	bool res;
 727
 728	if (kstrtobool(str, &res))
 729		return -EINVAL;
 730
 731	tm_disabled = !res;
 732
 733	return 0;
 734}
 735early_param("ppc_tm", parse_ppc_tm);
 736
 737static void __init tm_init(void)
 738{
 739	if (tm_disabled) {
 740		pr_info("Disabling hardware transactional memory (HTM)\n");
 741		cur_cpu_spec->cpu_user_features2 &=
 742			~(PPC_FEATURE2_HTM_NOSC | PPC_FEATURE2_HTM);
 743		cur_cpu_spec->cpu_features &= ~CPU_FTR_TM;
 744		return;
 745	}
 746
 747	pnv_tm_init();
 748}
 749#else
 750static void tm_init(void) { }
 751#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
 752
 753static int __init
 754early_init_dt_scan_model(unsigned long node, const char *uname,
 755			 int depth, void *data)
 756{
 757	const char *prop;
 758
 759	if (depth != 0)
 760		return 0;
 761
 762	prop = of_get_flat_dt_prop(node, "model", NULL);
 763	if (prop)
 764		seq_buf_printf(&ppc_hw_desc, "%s ", prop);
 765
 766	/* break now */
 767	return 1;
 768}
 769
 770#ifdef CONFIG_PPC64
 771static void __init save_fscr_to_task(void)
 772{
 773	/*
 774	 * Ensure the init_task (pid 0, aka swapper) uses the value of FSCR we
 775	 * have configured via the device tree features or via __init_FSCR().
 776	 * That value will then be propagated to pid 1 (init) and all future
 777	 * processes.
 778	 */
 779	if (early_cpu_has_feature(CPU_FTR_ARCH_207S))
 780		init_task.thread.fscr = mfspr(SPRN_FSCR);
 781}
 782#else
 783static inline void save_fscr_to_task(void) {}
 784#endif
 785
 786
 787void __init early_init_devtree(void *params)
 788{
 789	phys_addr_t int_vector_size;
 790
 791	DBG(" -> early_init_devtree(%px)\n", params);
 792
 793	/* Too early to BUG_ON(), do it by hand */
 794	if (!early_init_dt_verify(params, __pa(params)))
 795		panic("BUG: Failed verifying flat device tree, bad version?");
 796
 797	of_scan_flat_dt(early_init_dt_scan_model, NULL);
 798
 799#ifdef CONFIG_PPC_RTAS
 800	/* Some machines might need RTAS info for debugging, grab it now. */
 801	of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
 802#endif
 803
 804#ifdef CONFIG_PPC_POWERNV
 805	/* Some machines might need OPAL info for debugging, grab it now. */
 806	of_scan_flat_dt(early_init_dt_scan_opal, NULL);
 807
 808	/* Scan tree for ultravisor feature */
 809	of_scan_flat_dt(early_init_dt_scan_ultravisor, NULL);
 810#endif
 811
 812#if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)
 813	/* scan tree to see if dump is active during last boot */
 814	of_scan_flat_dt(early_init_dt_scan_fw_dump, NULL);
 815#endif
 816
 817	/* Retrieve various informations from the /chosen node of the
 818	 * device-tree, including the platform type, initrd location and
 819	 * size, TCE reserve, and more ...
 820	 */
 821	of_scan_flat_dt(early_init_dt_scan_chosen_ppc, boot_command_line);
 822
 823	/* Append additional parameters passed for fadump capture kernel */
 824	fadump_append_bootargs();
 825
 826	/* Scan memory nodes and rebuild MEMBLOCKs */
 827	early_init_dt_scan_root();
 828	early_init_dt_scan_memory_ppc();
 829
 830	/*
 831	 * As generic code authors expect to be able to use static keys
 832	 * in early_param() handlers, we initialize the static keys just
 833	 * before parsing early params (it's fine to call jump_label_init()
 834	 * more than once).
 835	 */
 836	jump_label_init();
 837	parse_early_param();
 838
 839	/* make sure we've parsed cmdline for mem= before this */
 840	if (memory_limit)
 841		first_memblock_size = min_t(u64, first_memblock_size, memory_limit);
 842	setup_initial_memory_limit(memstart_addr, first_memblock_size);
 843	/* Reserve MEMBLOCK regions used by kernel, initrd, dt, etc... */
 844	memblock_reserve(PHYSICAL_START, __pa(_end) - PHYSICAL_START);
 845#ifdef CONFIG_PPC64
 846	/* If relocatable, reserve at least 32k for interrupt vectors etc. */
 847	int_vector_size = __end_interrupts - _stext;
 848	int_vector_size = max_t(phys_addr_t, SZ_32K, int_vector_size);
 849#else
 850	/* If relocatable, reserve first 32k for interrupt vectors etc. */
 851	int_vector_size = SZ_32K;
 852#endif
 853	if (PHYSICAL_START > MEMORY_START)
 854		memblock_reserve(MEMORY_START, int_vector_size);
 855	reserve_kdump_trampoline();
 856#if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)
 857	/*
 858	 * If we fail to reserve memory for firmware-assisted dump then
 859	 * fallback to kexec based kdump.
 860	 */
 861	if (fadump_reserve_mem() == 0)
 862#endif
 863		reserve_crashkernel();
 864	early_reserve_mem();
 865
 866	if (memory_limit > memblock_phys_mem_size())
 867		memory_limit = 0;
 868
 869	/* Align down to 16 MB which is large page size with hash page translation */
 870	memory_limit = ALIGN_DOWN(memory_limit ?: memblock_phys_mem_size(), SZ_16M);
 871	memblock_enforce_memory_limit(memory_limit);
 872
 873#if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_PPC_4K_PAGES)
 874	if (!early_radix_enabled())
 875		memblock_cap_memory_range(0, 1UL << (H_MAX_PHYSMEM_BITS));
 876#endif
 877
 878	memblock_allow_resize();
 879	memblock_dump_all();
 880
 881	DBG("Phys. mem: %llx\n", (unsigned long long)memblock_phys_mem_size());
 882
 883	/* We may need to relocate the flat tree, do it now.
 884	 * FIXME .. and the initrd too? */
 885	move_device_tree();
 886
 
 
 887	DBG("Scanning CPUs ...\n");
 888
 889	dt_cpu_ftrs_scan();
 890
 891	/* Retrieve CPU related informations from the flat tree
 892	 * (altivec support, boot CPU ID, ...)
 893	 */
 894	of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
 895	if (boot_cpuid < 0) {
 896		printk("Failed to identify boot CPU !\n");
 897		BUG();
 898	}
 899
 900	save_fscr_to_task();
 901
 902#if defined(CONFIG_SMP) && defined(CONFIG_PPC64)
 903	/* We'll later wait for secondaries to check in; there are
 904	 * NCPUS-1 non-boot CPUs  :-)
 905	 */
 906	spinning_secondaries = boot_cpu_count - 1;
 907#endif
 908
 909	mmu_early_init_devtree();
 910
 911	/* Setup param area for passing additional parameters to fadump capture kernel. */
 912	fadump_setup_param_area();
 913
 914#ifdef CONFIG_PPC_POWERNV
 915	/* Scan and build the list of machine check recoverable ranges */
 916	of_scan_flat_dt(early_init_dt_scan_recoverable_ranges, NULL);
 917#endif
 918	epapr_paravirt_early_init();
 919
 920	/* Now try to figure out if we are running on LPAR and so on */
 921	pseries_probe_fw_features();
 922
 923	/*
 924	 * Initialize pkey features and default AMR/IAMR values
 925	 */
 926	pkey_early_init_devtree();
 927
 928#ifdef CONFIG_PPC_PS3
 929	/* Identify PS3 firmware */
 930	if (of_flat_dt_is_compatible(of_get_flat_dt_root(), "sony,ps3"))
 931		powerpc_firmware_features |= FW_FEATURE_PS3_POSSIBLE;
 932#endif
 933
 934	/* If kexec left a PLPKS password in the DT, get it and clear it */
 935	plpks_early_init_devtree();
 936
 937	tm_init();
 938
 939	DBG(" <- early_init_devtree()\n");
 940}
 941
 942#ifdef CONFIG_RELOCATABLE
 943/*
 944 * This function run before early_init_devtree, so we have to init
 945 * initial_boot_params.
 946 */
 947void __init early_get_first_memblock_info(void *params, phys_addr_t *size)
 948{
 949	/* Setup flat device-tree pointer */
 950	initial_boot_params = params;
 951
 952	/*
 953	 * Scan the memory nodes and set add_mem_to_memblock to 0 to avoid
 954	 * mess the memblock.
 955	 */
 956	add_mem_to_memblock = 0;
 957	early_init_dt_scan_root();
 958	early_init_dt_scan_memory_ppc();
 959	add_mem_to_memblock = 1;
 960
 961	if (size)
 962		*size = first_memblock_size;
 963}
 964#endif
 965
 966/*******
 967 *
 968 * New implementation of the OF "find" APIs, return a refcounted
 969 * object, call of_node_put() when done.  The device tree and list
 970 * are protected by a rw_lock.
 971 *
 972 * Note that property management will need some locking as well,
 973 * this isn't dealt with yet.
 974 *
 975 *******/
 976
 977/**
 978 * of_get_ibm_chip_id - Returns the IBM "chip-id" of a device
 979 * @np: device node of the device
 980 *
 981 * This looks for a property "ibm,chip-id" in the node or any
 982 * of its parents and returns its content, or -1 if it cannot
 983 * be found.
 984 */
 985int of_get_ibm_chip_id(struct device_node *np)
 986{
 987	of_node_get(np);
 988	while (np) {
 989		u32 chip_id;
 990
 991		/*
 992		 * Skiboot may produce memory nodes that contain more than one
 993		 * cell in chip-id, we only read the first one here.
 994		 */
 995		if (!of_property_read_u32(np, "ibm,chip-id", &chip_id)) {
 996			of_node_put(np);
 997			return chip_id;
 998		}
 999
1000		np = of_get_next_parent(np);
1001	}
1002	return -1;
1003}
1004EXPORT_SYMBOL(of_get_ibm_chip_id);
1005
1006/**
1007 * cpu_to_chip_id - Return the cpus chip-id
1008 * @cpu: The logical cpu number.
1009 *
1010 * Return the value of the ibm,chip-id property corresponding to the given
1011 * logical cpu number. If the chip-id can not be found, returns -1.
1012 */
1013int cpu_to_chip_id(int cpu)
1014{
1015	struct device_node *np;
1016	int ret = -1, idx;
1017
1018	idx = cpu / threads_per_core;
1019	if (chip_id_lookup_table && chip_id_lookup_table[idx] != -1)
1020		return chip_id_lookup_table[idx];
1021
1022	np = of_get_cpu_node(cpu, NULL);
1023	if (np) {
1024		ret = of_get_ibm_chip_id(np);
1025		of_node_put(np);
1026
1027		if (chip_id_lookup_table)
1028			chip_id_lookup_table[idx] = ret;
1029	}
1030
1031	return ret;
1032}
1033EXPORT_SYMBOL(cpu_to_chip_id);
1034
1035bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
1036{
1037#ifdef CONFIG_SMP
1038	/*
1039	 * Early firmware scanning must use this rather than
1040	 * get_hard_smp_processor_id because we don't have pacas allocated
1041	 * until memory topology is discovered.
1042	 */
1043	if (cpu_to_phys_id != NULL)
1044		return (int)phys_id == cpu_to_phys_id[cpu];
1045#endif
1046
1047	return (int)phys_id == get_hard_smp_processor_id(cpu);
1048}