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(fmt: "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, size: &tablelen);
249 if (pa_ftrs == NULL)
250 return;
251
252 scan_features(node, ftrs: pa_ftrs, tablelen, fp, ft_size: 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, name: fp->name, NULL);
322 if (prop && be32_to_cpup(p: 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, name: "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, name: "ibm,ppc-interrupt-server#s", size: &len);
350 if (!intserv)
351 intserv = of_get_flat_dt_prop(node, name: "reg", size: &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, name: "cpu-version", NULL);
421 if (prop && (be32_to_cpup(p: prop) & 0xff000000) == 0x0f000000) {
422 identify_cpu(0, be32_to_cpup(p: prop));
423 seq_buf_printf(s: &ppc_hw_desc, fmt: "0x%04x ", be32_to_cpup(p: 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(cmdline: 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, name: "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, name: "linux,crashkernel-base", NULL);
480 if (lprop)
481 crashk_res.start = *lprop;
482
483 lprop = of_get_flat_dt_prop(node, name: "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: &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(node: dt_root, name: "reserved-ranges", size: &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(cell: prop + (i * 4) + 0, size: 2);
661 size = of_read_number(cell: prop + (i * 4) + 2, size: 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(p: 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(p: reserve_map_32++);
704 size_32 = be32_to_cpup(p: reserve_map_32++);
705 if (size_32 == 0)
706 break;
707 DBG("reserving: %x -> %x\n", base_32, size_32);
708 memblock_reserve(base: base_32, size: 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, name: "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(fmt: "BUG: Failed verifying flat device tree, bad version?");
789
790 of_scan_flat_dt(it: 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(it: early_init_dt_scan_chosen_ppc, data: 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(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(it: 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(node: 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, propname: "ibm,chip-id", out_value: &chip_id)) {
976 of_node_put(node: np);
977 return chip_id;
978 }
979
980 np = of_get_next_parent(node: 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(node: 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}
1029

source code of linux/arch/powerpc/kernel/prom.c