xref: /linux/arch/powerpc/kernel/prom.c (revision da51bbcdbace8f43adf6066934c3926b656376e5)
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 
69 int *chip_id_lookup_table;
70 
71 #ifdef CONFIG_PPC64
72 int __initdata iommu_is_off;
73 int __initdata iommu_force_on;
74 unsigned long tce_alloc_start, tce_alloc_end;
75 u64 ppc64_rma_size;
76 unsigned int boot_cpu_node_count __ro_after_init;
77 #endif
78 static phys_addr_t first_memblock_size;
79 static int __initdata boot_cpu_count;
80 
81 static 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 }
91 early_param("mem", early_parse_mem);
92 
93 /*
94  * overlaps_initrd - check for overlap with page aligned extension of
95  * initrd.
96  */
97 static 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  */
117 static 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  */
158 struct 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 
168 static 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  */
197 static 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 
202 static 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 
241 static 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
256 static 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 
270 static 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)
292 static __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 
314 static 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 
329 static int __init early_init_dt_scan_cpus(unsigned long node,
330 					  const char *uname, int depth,
331 					  void *data)
332 {
333 	const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
334 	const __be32 *prop;
335 	const __be32 *intserv;
336 	int i, nthreads;
337 	int len;
338 	int found = -1;
339 	int found_thread = 0;
340 
341 	/* We are scanning "cpu" nodes only */
342 	if (type == NULL || strcmp(type, "cpu") != 0)
343 		return 0;
344 
345 	if (IS_ENABLED(CONFIG_PPC64))
346 		boot_cpu_node_count++;
347 
348 	/* Get physical cpuid */
349 	intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
350 	if (!intserv)
351 		intserv = of_get_flat_dt_prop(node, "reg", &len);
352 
353 	nthreads = len / sizeof(int);
354 
355 	/*
356 	 * Now see if any of these threads match our boot cpu.
357 	 * NOTE: This must match the parsing done in smp_setup_cpu_maps.
358 	 */
359 	for (i = 0; i < nthreads; i++) {
360 		if (be32_to_cpu(intserv[i]) ==
361 			fdt_boot_cpuid_phys(initial_boot_params)) {
362 			found = boot_cpu_count;
363 			found_thread = i;
364 		}
365 #ifdef CONFIG_SMP
366 		/* logical cpu id is always 0 on UP kernels */
367 		boot_cpu_count++;
368 #endif
369 	}
370 
371 	/* Not the boot CPU */
372 	if (found < 0)
373 		return 0;
374 
375 	boot_cpuid = found;
376 
377 	if (IS_ENABLED(CONFIG_PPC64))
378 		boot_cpu_hwid = be32_to_cpu(intserv[found_thread]);
379 
380 	if (nr_cpu_ids % nthreads != 0) {
381 		set_nr_cpu_ids(ALIGN(nr_cpu_ids, nthreads));
382 		pr_warn("nr_cpu_ids was not a multiple of threads_per_core, adjusted to %d\n",
383 			nr_cpu_ids);
384 	}
385 
386 	if (boot_cpuid >= nr_cpu_ids) {
387 		// Remember boot core for smp_setup_cpu_maps()
388 		boot_core_hwid = be32_to_cpu(intserv[0]);
389 
390 		pr_warn("Boot CPU %d (core hwid %d) >= nr_cpu_ids, adjusted boot CPU to %d\n",
391 			boot_cpuid, boot_core_hwid, found_thread);
392 
393 		// Adjust boot CPU to appear on logical core 0
394 		boot_cpuid = found_thread;
395 	}
396 
397 	DBG("boot cpu: logical %d physical %d\n", boot_cpuid,
398 	    be32_to_cpu(intserv[found_thread]));
399 
400 	/*
401 	 * PAPR defines "logical" PVR values for cpus that
402 	 * meet various levels of the architecture:
403 	 * 0x0f000001	Architecture version 2.04
404 	 * 0x0f000002	Architecture version 2.05
405 	 * If the cpu-version property in the cpu node contains
406 	 * such a value, we call identify_cpu again with the
407 	 * logical PVR value in order to use the cpu feature
408 	 * bits appropriate for the architecture level.
409 	 *
410 	 * A POWER6 partition in "POWER6 architected" mode
411 	 * uses the 0x0f000002 PVR value; in POWER5+ mode
412 	 * it uses 0x0f000001.
413 	 *
414 	 * If we're using device tree CPU feature discovery then we don't
415 	 * support the cpu-version property, and it's the responsibility of the
416 	 * firmware/hypervisor to provide the correct feature set for the
417 	 * architecture level via the ibm,powerpc-cpu-features binding.
418 	 */
419 	if (!dt_cpu_ftrs_in_use()) {
420 		prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
421 		if (prop && (be32_to_cpup(prop) & 0xff000000) == 0x0f000000) {
422 			identify_cpu(0, be32_to_cpup(prop));
423 			seq_buf_printf(&ppc_hw_desc, "0x%04x ", be32_to_cpup(prop));
424 		}
425 
426 		check_cpu_feature_properties(node);
427 		check_cpu_features(node, "ibm,pa-features", ibm_pa_features,
428 				   ARRAY_SIZE(ibm_pa_features));
429 		check_cpu_features(node, "ibm,pi-features", ibm_pi_features,
430 				   ARRAY_SIZE(ibm_pi_features));
431 	}
432 
433 	identical_pvr_fixup(node);
434 	init_mmu_slb_size(node);
435 
436 #ifdef CONFIG_PPC64
437 	if (nthreads == 1)
438 		cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
439 	else if (!dt_cpu_ftrs_in_use())
440 		cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
441 #endif
442 
443 	return 0;
444 }
445 
446 static int __init early_init_dt_scan_chosen_ppc(unsigned long node,
447 						const char *uname,
448 						int depth, void *data)
449 {
450 	const unsigned long *lprop; /* All these set by kernel, so no need to convert endian */
451 
452 	/* Use common scan routine to determine if this is the chosen node */
453 	if (early_init_dt_scan_chosen(data) < 0)
454 		return 0;
455 
456 #ifdef CONFIG_PPC64
457 	/* check if iommu is forced on or off */
458 	if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
459 		iommu_is_off = 1;
460 	if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
461 		iommu_force_on = 1;
462 #endif
463 
464 	/* mem=x on the command line is the preferred mechanism */
465 	lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
466 	if (lprop)
467 		memory_limit = *lprop;
468 
469 #ifdef CONFIG_PPC64
470 	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
471 	if (lprop)
472 		tce_alloc_start = *lprop;
473 	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
474 	if (lprop)
475 		tce_alloc_end = *lprop;
476 #endif
477 
478 #ifdef CONFIG_CRASH_RESERVE
479 	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
480 	if (lprop)
481 		crashk_res.start = *lprop;
482 
483 	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
484 	if (lprop)
485 		crashk_res.end = crashk_res.start + *lprop - 1;
486 #endif
487 
488 	/* break now */
489 	return 1;
490 }
491 
492 /*
493  * Compare the range against max mem limit and update
494  * size if it cross the limit.
495  */
496 
497 #ifdef CONFIG_SPARSEMEM
498 static 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
509 static 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  */
521 static 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 
583 static 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
606 static int add_mem_to_memblock = 1;
607 #else
608 #define add_mem_to_memblock 1
609 #endif
610 
611 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
612 {
613 #ifdef CONFIG_PPC64
614 	if (iommu_is_off) {
615 		if (base >= 0x80000000ul)
616 			return;
617 		if ((base + size) > 0x80000000ul)
618 			size = 0x80000000ul - base;
619 	}
620 #endif
621 	/* Keep track of the beginning of memory -and- the size of
622 	 * the very first block in the device-tree as it represents
623 	 * the RMA on ppc64 server
624 	 */
625 	if (base < memstart_addr) {
626 		memstart_addr = base;
627 		first_memblock_size = size;
628 	}
629 
630 	/* Add the chunk to the MEMBLOCK list */
631 	if (add_mem_to_memblock) {
632 		if (validate_mem_limit(base, &size))
633 			memblock_add(base, size);
634 	}
635 }
636 
637 static void __init early_reserve_mem_dt(void)
638 {
639 	unsigned long i, dt_root;
640 	int len;
641 	const __be32 *prop;
642 
643 	early_init_fdt_reserve_self();
644 	early_init_fdt_scan_reserved_mem();
645 
646 	dt_root = of_get_flat_dt_root();
647 
648 	prop = of_get_flat_dt_prop(dt_root, "reserved-ranges", &len);
649 
650 	if (!prop)
651 		return;
652 
653 	DBG("Found new-style reserved-ranges\n");
654 
655 	/* Each reserved range is an (address,size) pair, 2 cells each,
656 	 * totalling 4 cells per range. */
657 	for (i = 0; i < len / (sizeof(*prop) * 4); i++) {
658 		u64 base, size;
659 
660 		base = of_read_number(prop + (i * 4) + 0, 2);
661 		size = of_read_number(prop + (i * 4) + 2, 2);
662 
663 		if (size) {
664 			DBG("reserving: %llx -> %llx\n", base, size);
665 			memblock_reserve(base, size);
666 		}
667 	}
668 }
669 
670 static void __init early_reserve_mem(void)
671 {
672 	__be64 *reserve_map;
673 
674 	reserve_map = (__be64 *)(((unsigned long)initial_boot_params) +
675 			fdt_off_mem_rsvmap(initial_boot_params));
676 
677 	/* Look for the new "reserved-regions" property in the DT */
678 	early_reserve_mem_dt();
679 
680 #ifdef CONFIG_BLK_DEV_INITRD
681 	/* Then reserve the initrd, if any */
682 	if (initrd_start && (initrd_end > initrd_start)) {
683 		memblock_reserve(ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
684 			ALIGN(initrd_end, PAGE_SIZE) -
685 			ALIGN_DOWN(initrd_start, PAGE_SIZE));
686 	}
687 #endif /* CONFIG_BLK_DEV_INITRD */
688 
689 	if (!IS_ENABLED(CONFIG_PPC32))
690 		return;
691 
692 	/*
693 	 * Handle the case where we might be booting from an old kexec
694 	 * image that setup the mem_rsvmap as pairs of 32-bit values
695 	 */
696 	if (be64_to_cpup(reserve_map) > 0xffffffffull) {
697 		u32 base_32, size_32;
698 		__be32 *reserve_map_32 = (__be32 *)reserve_map;
699 
700 		DBG("Found old 32-bit reserve map\n");
701 
702 		while (1) {
703 			base_32 = be32_to_cpup(reserve_map_32++);
704 			size_32 = be32_to_cpup(reserve_map_32++);
705 			if (size_32 == 0)
706 				break;
707 			DBG("reserving: %x -> %x\n", base_32, size_32);
708 			memblock_reserve(base_32, size_32);
709 		}
710 		return;
711 	}
712 }
713 
714 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
715 static bool tm_disabled __initdata;
716 
717 static 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 }
728 early_param("ppc_tm", parse_ppc_tm);
729 
730 static 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
743 static void tm_init(void) { }
744 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
745 
746 static int __init
747 early_init_dt_scan_model(unsigned long node, const char *uname,
748 			 int depth, void *data)
749 {
750 	const char *prop;
751 
752 	if (depth != 0)
753 		return 0;
754 
755 	prop = of_get_flat_dt_prop(node, "model", NULL);
756 	if (prop)
757 		seq_buf_printf(&ppc_hw_desc, "%s ", prop);
758 
759 	/* break now */
760 	return 1;
761 }
762 
763 #ifdef CONFIG_PPC64
764 static 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
776 static inline void save_fscr_to_task(void) {}
777 #endif
778 
779 
780 void __init early_init_devtree(void *params)
781 {
782 	phys_addr_t limit;
783 
784 	DBG(" -> early_init_devtree(%px)\n", params);
785 
786 	/* Too early to BUG_ON(), do it by hand */
787 	if (!early_init_dt_verify(params))
788 		panic("BUG: Failed verifying flat device tree, bad version?");
789 
790 	of_scan_flat_dt(early_init_dt_scan_model, NULL);
791 
792 #ifdef CONFIG_PPC_RTAS
793 	/* Some machines might need RTAS info for debugging, grab it now. */
794 	of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
795 #endif
796 
797 #ifdef CONFIG_PPC_POWERNV
798 	/* Some machines might need OPAL info for debugging, grab it now. */
799 	of_scan_flat_dt(early_init_dt_scan_opal, NULL);
800 
801 	/* Scan tree for ultravisor feature */
802 	of_scan_flat_dt(early_init_dt_scan_ultravisor, NULL);
803 #endif
804 
805 #if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)
806 	/* scan tree to see if dump is active during last boot */
807 	of_scan_flat_dt(early_init_dt_scan_fw_dump, NULL);
808 #endif
809 
810 	/* Retrieve various informations from the /chosen node of the
811 	 * device-tree, including the platform type, initrd location and
812 	 * size, TCE reserve, and more ...
813 	 */
814 	of_scan_flat_dt(early_init_dt_scan_chosen_ppc, boot_command_line);
815 
816 	/* Scan memory nodes and rebuild MEMBLOCKs */
817 	early_init_dt_scan_root();
818 	early_init_dt_scan_memory_ppc();
819 
820 	/*
821 	 * As generic code authors expect to be able to use static keys
822 	 * in early_param() handlers, we initialize the static keys just
823 	 * before parsing early params (it's fine to call jump_label_init()
824 	 * more than once).
825 	 */
826 	jump_label_init();
827 	parse_early_param();
828 
829 	/* make sure we've parsed cmdline for mem= before this */
830 	if (memory_limit)
831 		first_memblock_size = min_t(u64, first_memblock_size, memory_limit);
832 	setup_initial_memory_limit(memstart_addr, first_memblock_size);
833 	/* Reserve MEMBLOCK regions used by kernel, initrd, dt, etc... */
834 	memblock_reserve(PHYSICAL_START, __pa(_end) - PHYSICAL_START);
835 	/* If relocatable, reserve first 32k for interrupt vectors etc. */
836 	if (PHYSICAL_START > MEMORY_START)
837 		memblock_reserve(MEMORY_START, 0x8000);
838 	reserve_kdump_trampoline();
839 #if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)
840 	/*
841 	 * If we fail to reserve memory for firmware-assisted dump then
842 	 * fallback to kexec based kdump.
843 	 */
844 	if (fadump_reserve_mem() == 0)
845 #endif
846 		reserve_crashkernel();
847 	early_reserve_mem();
848 
849 	/* Ensure that total memory size is page-aligned. */
850 	limit = ALIGN(memory_limit ?: memblock_phys_mem_size(), PAGE_SIZE);
851 	memblock_enforce_memory_limit(limit);
852 
853 #if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_PPC_4K_PAGES)
854 	if (!early_radix_enabled())
855 		memblock_cap_memory_range(0, 1UL << (H_MAX_PHYSMEM_BITS));
856 #endif
857 
858 	memblock_allow_resize();
859 	memblock_dump_all();
860 
861 	DBG("Phys. mem: %llx\n", (unsigned long long)memblock_phys_mem_size());
862 
863 	/* We may need to relocate the flat tree, do it now.
864 	 * FIXME .. and the initrd too? */
865 	move_device_tree();
866 
867 	DBG("Scanning CPUs ...\n");
868 
869 	dt_cpu_ftrs_scan();
870 
871 	// We can now add the CPU name & PVR to the hardware description
872 	seq_buf_printf(&ppc_hw_desc, "%s 0x%04lx ", cur_cpu_spec->cpu_name, mfspr(SPRN_PVR));
873 
874 	/* Retrieve CPU related informations from the flat tree
875 	 * (altivec support, boot CPU ID, ...)
876 	 */
877 	of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
878 	if (boot_cpuid < 0) {
879 		printk("Failed to identify boot CPU !\n");
880 		BUG();
881 	}
882 
883 	save_fscr_to_task();
884 
885 #if defined(CONFIG_SMP) && defined(CONFIG_PPC64)
886 	/* We'll later wait for secondaries to check in; there are
887 	 * NCPUS-1 non-boot CPUs  :-)
888 	 */
889 	spinning_secondaries = boot_cpu_count - 1;
890 #endif
891 
892 	mmu_early_init_devtree();
893 
894 #ifdef CONFIG_PPC_POWERNV
895 	/* Scan and build the list of machine check recoverable ranges */
896 	of_scan_flat_dt(early_init_dt_scan_recoverable_ranges, NULL);
897 #endif
898 	epapr_paravirt_early_init();
899 
900 	/* Now try to figure out if we are running on LPAR and so on */
901 	pseries_probe_fw_features();
902 
903 	/*
904 	 * Initialize pkey features and default AMR/IAMR values
905 	 */
906 	pkey_early_init_devtree();
907 
908 #ifdef CONFIG_PPC_PS3
909 	/* Identify PS3 firmware */
910 	if (of_flat_dt_is_compatible(of_get_flat_dt_root(), "sony,ps3"))
911 		powerpc_firmware_features |= FW_FEATURE_PS3_POSSIBLE;
912 #endif
913 
914 	/* If kexec left a PLPKS password in the DT, get it and clear it */
915 	plpks_early_init_devtree();
916 
917 	tm_init();
918 
919 	DBG(" <- early_init_devtree()\n");
920 }
921 
922 #ifdef CONFIG_RELOCATABLE
923 /*
924  * This function run before early_init_devtree, so we have to init
925  * initial_boot_params.
926  */
927 void __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  */
965 int of_get_ibm_chip_id(struct device_node *np)
966 {
967 	of_node_get(np);
968 	while (np) {
969 		u32 chip_id;
970 
971 		/*
972 		 * Skiboot may produce memory nodes that contain more than one
973 		 * cell in chip-id, we only read the first one here.
974 		 */
975 		if (!of_property_read_u32(np, "ibm,chip-id", &chip_id)) {
976 			of_node_put(np);
977 			return chip_id;
978 		}
979 
980 		np = of_get_next_parent(np);
981 	}
982 	return -1;
983 }
984 EXPORT_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  */
993 int cpu_to_chip_id(int cpu)
994 {
995 	struct device_node *np;
996 	int ret = -1, idx;
997 
998 	idx = cpu / threads_per_core;
999 	if (chip_id_lookup_table && chip_id_lookup_table[idx] != -1)
1000 		return chip_id_lookup_table[idx];
1001 
1002 	np = of_get_cpu_node(cpu, NULL);
1003 	if (np) {
1004 		ret = of_get_ibm_chip_id(np);
1005 		of_node_put(np);
1006 
1007 		if (chip_id_lookup_table)
1008 			chip_id_lookup_table[idx] = ret;
1009 	}
1010 
1011 	return ret;
1012 }
1013 EXPORT_SYMBOL(cpu_to_chip_id);
1014 
1015 bool 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