xref: /openbmc/linux/arch/powerpc/kernel/prom.c (revision 9cdb81c7)
1 /*
2  * Procedures for creating, accessing and interpreting the device tree.
3  *
4  * Paul Mackerras	August 1996.
5  * Copyright (C) 1996-2005 Paul Mackerras.
6  *
7  *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
8  *    {engebret|bergner}@us.ibm.com
9  *
10  *      This program is free software; you can redistribute it and/or
11  *      modify it under the terms of the GNU General Public License
12  *      as published by the Free Software Foundation; either version
13  *      2 of the License, or (at your option) any later version.
14  */
15 
16 #undef DEBUG
17 
18 #include <stdarg.h>
19 #include <linux/kernel.h>
20 #include <linux/string.h>
21 #include <linux/init.h>
22 #include <linux/threads.h>
23 #include <linux/spinlock.h>
24 #include <linux/types.h>
25 #include <linux/pci.h>
26 #include <linux/stringify.h>
27 #include <linux/delay.h>
28 #include <linux/initrd.h>
29 #include <linux/bitops.h>
30 #include <linux/export.h>
31 #include <linux/kexec.h>
32 #include <linux/debugfs.h>
33 #include <linux/irq.h>
34 #include <linux/memblock.h>
35 
36 #include <asm/prom.h>
37 #include <asm/rtas.h>
38 #include <asm/page.h>
39 #include <asm/processor.h>
40 #include <asm/irq.h>
41 #include <asm/io.h>
42 #include <asm/kdump.h>
43 #include <asm/smp.h>
44 #include <asm/system.h>
45 #include <asm/mmu.h>
46 #include <asm/paca.h>
47 #include <asm/pgtable.h>
48 #include <asm/pci.h>
49 #include <asm/iommu.h>
50 #include <asm/btext.h>
51 #include <asm/sections.h>
52 #include <asm/machdep.h>
53 #include <asm/pSeries_reconfig.h>
54 #include <asm/pci-bridge.h>
55 #include <asm/kexec.h>
56 #include <asm/opal.h>
57 #include <asm/fadump.h>
58 
59 #include <mm/mmu_decl.h>
60 
61 #ifdef DEBUG
62 #define DBG(fmt...) printk(KERN_ERR fmt)
63 #else
64 #define DBG(fmt...)
65 #endif
66 
67 #ifdef CONFIG_PPC64
68 int __initdata iommu_is_off;
69 int __initdata iommu_force_on;
70 unsigned long tce_alloc_start, tce_alloc_end;
71 u64 ppc64_rma_size;
72 #endif
73 static phys_addr_t first_memblock_size;
74 static int __initdata boot_cpu_count;
75 
76 static int __init early_parse_mem(char *p)
77 {
78 	if (!p)
79 		return 1;
80 
81 	memory_limit = PAGE_ALIGN(memparse(p, &p));
82 	DBG("memory limit = 0x%llx\n", (unsigned long long)memory_limit);
83 
84 	return 0;
85 }
86 early_param("mem", early_parse_mem);
87 
88 /*
89  * overlaps_initrd - check for overlap with page aligned extension of
90  * initrd.
91  */
92 static inline int overlaps_initrd(unsigned long start, unsigned long size)
93 {
94 #ifdef CONFIG_BLK_DEV_INITRD
95 	if (!initrd_start)
96 		return 0;
97 
98 	return	(start + size) > _ALIGN_DOWN(initrd_start, PAGE_SIZE) &&
99 			start <= _ALIGN_UP(initrd_end, PAGE_SIZE);
100 #else
101 	return 0;
102 #endif
103 }
104 
105 /**
106  * move_device_tree - move tree to an unused area, if needed.
107  *
108  * The device tree may be allocated beyond our memory limit, or inside the
109  * crash kernel region for kdump, or within the page aligned range of initrd.
110  * If so, move it out of the way.
111  */
112 static void __init move_device_tree(void)
113 {
114 	unsigned long start, size;
115 	void *p;
116 
117 	DBG("-> move_device_tree\n");
118 
119 	start = __pa(initial_boot_params);
120 	size = be32_to_cpu(initial_boot_params->totalsize);
121 
122 	if ((memory_limit && (start + size) > PHYSICAL_START + memory_limit) ||
123 			overlaps_crashkernel(start, size) ||
124 			overlaps_initrd(start, size)) {
125 		p = __va(memblock_alloc(size, PAGE_SIZE));
126 		memcpy(p, initial_boot_params, size);
127 		initial_boot_params = (struct boot_param_header *)p;
128 		DBG("Moved device tree to 0x%p\n", p);
129 	}
130 
131 	DBG("<- move_device_tree\n");
132 }
133 
134 /*
135  * ibm,pa-features is a per-cpu property that contains a string of
136  * attribute descriptors, each of which has a 2 byte header plus up
137  * to 254 bytes worth of processor attribute bits.  First header
138  * byte specifies the number of bytes following the header.
139  * Second header byte is an "attribute-specifier" type, of which
140  * zero is the only currently-defined value.
141  * Implementation:  Pass in the byte and bit offset for the feature
142  * that we are interested in.  The function will return -1 if the
143  * pa-features property is missing, or a 1/0 to indicate if the feature
144  * is supported/not supported.  Note that the bit numbers are
145  * big-endian to match the definition in PAPR.
146  */
147 static struct ibm_pa_feature {
148 	unsigned long	cpu_features;	/* CPU_FTR_xxx bit */
149 	unsigned long	mmu_features;	/* MMU_FTR_xxx bit */
150 	unsigned int	cpu_user_ftrs;	/* PPC_FEATURE_xxx bit */
151 	unsigned char	pabyte;		/* byte number in ibm,pa-features */
152 	unsigned char	pabit;		/* bit number (big-endian) */
153 	unsigned char	invert;		/* if 1, pa bit set => clear feature */
154 } ibm_pa_features[] __initdata = {
155 	{0, 0, PPC_FEATURE_HAS_MMU,	0, 0, 0},
156 	{0, 0, PPC_FEATURE_HAS_FPU,	0, 1, 0},
157 	{0, MMU_FTR_SLB, 0,		0, 2, 0},
158 	{CPU_FTR_CTRL, 0, 0,		0, 3, 0},
159 	{CPU_FTR_NOEXECUTE, 0, 0,	0, 6, 0},
160 	{CPU_FTR_NODSISRALIGN, 0, 0,	1, 1, 1},
161 	{0, MMU_FTR_CI_LARGE_PAGE, 0,	1, 2, 0},
162 	{CPU_FTR_REAL_LE, PPC_FEATURE_TRUE_LE, 5, 0, 0},
163 };
164 
165 static void __init scan_features(unsigned long node, unsigned char *ftrs,
166 				 unsigned long tablelen,
167 				 struct ibm_pa_feature *fp,
168 				 unsigned long ft_size)
169 {
170 	unsigned long i, len, bit;
171 
172 	/* find descriptor with type == 0 */
173 	for (;;) {
174 		if (tablelen < 3)
175 			return;
176 		len = 2 + ftrs[0];
177 		if (tablelen < len)
178 			return;		/* descriptor 0 not found */
179 		if (ftrs[1] == 0)
180 			break;
181 		tablelen -= len;
182 		ftrs += len;
183 	}
184 
185 	/* loop over bits we know about */
186 	for (i = 0; i < ft_size; ++i, ++fp) {
187 		if (fp->pabyte >= ftrs[0])
188 			continue;
189 		bit = (ftrs[2 + fp->pabyte] >> (7 - fp->pabit)) & 1;
190 		if (bit ^ fp->invert) {
191 			cur_cpu_spec->cpu_features |= fp->cpu_features;
192 			cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftrs;
193 			cur_cpu_spec->mmu_features |= fp->mmu_features;
194 		} else {
195 			cur_cpu_spec->cpu_features &= ~fp->cpu_features;
196 			cur_cpu_spec->cpu_user_features &= ~fp->cpu_user_ftrs;
197 			cur_cpu_spec->mmu_features &= ~fp->mmu_features;
198 		}
199 	}
200 }
201 
202 static void __init check_cpu_pa_features(unsigned long node)
203 {
204 	unsigned char *pa_ftrs;
205 	unsigned long tablelen;
206 
207 	pa_ftrs = of_get_flat_dt_prop(node, "ibm,pa-features", &tablelen);
208 	if (pa_ftrs == NULL)
209 		return;
210 
211 	scan_features(node, pa_ftrs, tablelen,
212 		      ibm_pa_features, ARRAY_SIZE(ibm_pa_features));
213 }
214 
215 #ifdef CONFIG_PPC_STD_MMU_64
216 static void __init check_cpu_slb_size(unsigned long node)
217 {
218 	u32 *slb_size_ptr;
219 
220 	slb_size_ptr = of_get_flat_dt_prop(node, "slb-size", NULL);
221 	if (slb_size_ptr != NULL) {
222 		mmu_slb_size = *slb_size_ptr;
223 		return;
224 	}
225 	slb_size_ptr = of_get_flat_dt_prop(node, "ibm,slb-size", NULL);
226 	if (slb_size_ptr != NULL) {
227 		mmu_slb_size = *slb_size_ptr;
228 	}
229 }
230 #else
231 #define check_cpu_slb_size(node) do { } while(0)
232 #endif
233 
234 static struct feature_property {
235 	const char *name;
236 	u32 min_value;
237 	unsigned long cpu_feature;
238 	unsigned long cpu_user_ftr;
239 } feature_properties[] __initdata = {
240 #ifdef CONFIG_ALTIVEC
241 	{"altivec", 0, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
242 	{"ibm,vmx", 1, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
243 #endif /* CONFIG_ALTIVEC */
244 #ifdef CONFIG_VSX
245 	/* Yes, this _really_ is ibm,vmx == 2 to enable VSX */
246 	{"ibm,vmx", 2, CPU_FTR_VSX, PPC_FEATURE_HAS_VSX},
247 #endif /* CONFIG_VSX */
248 #ifdef CONFIG_PPC64
249 	{"ibm,dfp", 1, 0, PPC_FEATURE_HAS_DFP},
250 	{"ibm,purr", 1, CPU_FTR_PURR, 0},
251 	{"ibm,spurr", 1, CPU_FTR_SPURR, 0},
252 #endif /* CONFIG_PPC64 */
253 };
254 
255 #if defined(CONFIG_44x) && defined(CONFIG_PPC_FPU)
256 static inline void identical_pvr_fixup(unsigned long node)
257 {
258 	unsigned int pvr;
259 	char *model = of_get_flat_dt_prop(node, "model", NULL);
260 
261 	/*
262 	 * Since 440GR(x)/440EP(x) processors have the same pvr,
263 	 * we check the node path and set bit 28 in the cur_cpu_spec
264 	 * pvr for EP(x) processor version. This bit is always 0 in
265 	 * the "real" pvr. Then we call identify_cpu again with
266 	 * the new logical pvr to enable FPU support.
267 	 */
268 	if (model && strstr(model, "440EP")) {
269 		pvr = cur_cpu_spec->pvr_value | 0x8;
270 		identify_cpu(0, pvr);
271 		DBG("Using logical pvr %x for %s\n", pvr, model);
272 	}
273 }
274 #else
275 #define identical_pvr_fixup(node) do { } while(0)
276 #endif
277 
278 static void __init check_cpu_feature_properties(unsigned long node)
279 {
280 	unsigned long i;
281 	struct feature_property *fp = feature_properties;
282 	const u32 *prop;
283 
284 	for (i = 0; i < ARRAY_SIZE(feature_properties); ++i, ++fp) {
285 		prop = of_get_flat_dt_prop(node, fp->name, NULL);
286 		if (prop && *prop >= fp->min_value) {
287 			cur_cpu_spec->cpu_features |= fp->cpu_feature;
288 			cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftr;
289 		}
290 	}
291 }
292 
293 static int __init early_init_dt_scan_cpus(unsigned long node,
294 					  const char *uname, int depth,
295 					  void *data)
296 {
297 	char *type = of_get_flat_dt_prop(node, "device_type", NULL);
298 	const u32 *prop;
299 	const u32 *intserv;
300 	int i, nthreads;
301 	unsigned long len;
302 	int found = -1;
303 	int found_thread = 0;
304 
305 	/* We are scanning "cpu" nodes only */
306 	if (type == NULL || strcmp(type, "cpu") != 0)
307 		return 0;
308 
309 	/* Get physical cpuid */
310 	intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
311 	if (intserv) {
312 		nthreads = len / sizeof(int);
313 	} else {
314 		intserv = of_get_flat_dt_prop(node, "reg", NULL);
315 		nthreads = 1;
316 	}
317 
318 	/*
319 	 * Now see if any of these threads match our boot cpu.
320 	 * NOTE: This must match the parsing done in smp_setup_cpu_maps.
321 	 */
322 	for (i = 0; i < nthreads; i++) {
323 		/*
324 		 * version 2 of the kexec param format adds the phys cpuid of
325 		 * booted proc.
326 		 */
327 		if (initial_boot_params->version >= 2) {
328 			if (intserv[i] == initial_boot_params->boot_cpuid_phys) {
329 				found = boot_cpu_count;
330 				found_thread = i;
331 			}
332 		} else {
333 			/*
334 			 * Check if it's the boot-cpu, set it's hw index now,
335 			 * unfortunately this format did not support booting
336 			 * off secondary threads.
337 			 */
338 			if (of_get_flat_dt_prop(node,
339 					"linux,boot-cpu", NULL) != NULL)
340 				found = boot_cpu_count;
341 		}
342 #ifdef CONFIG_SMP
343 		/* logical cpu id is always 0 on UP kernels */
344 		boot_cpu_count++;
345 #endif
346 	}
347 
348 	if (found >= 0) {
349 		DBG("boot cpu: logical %d physical %d\n", found,
350 			intserv[found_thread]);
351 		boot_cpuid = found;
352 		set_hard_smp_processor_id(found, intserv[found_thread]);
353 
354 		/*
355 		 * PAPR defines "logical" PVR values for cpus that
356 		 * meet various levels of the architecture:
357 		 * 0x0f000001	Architecture version 2.04
358 		 * 0x0f000002	Architecture version 2.05
359 		 * If the cpu-version property in the cpu node contains
360 		 * such a value, we call identify_cpu again with the
361 		 * logical PVR value in order to use the cpu feature
362 		 * bits appropriate for the architecture level.
363 		 *
364 		 * A POWER6 partition in "POWER6 architected" mode
365 		 * uses the 0x0f000002 PVR value; in POWER5+ mode
366 		 * it uses 0x0f000001.
367 		 */
368 		prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
369 		if (prop && (*prop & 0xff000000) == 0x0f000000)
370 			identify_cpu(0, *prop);
371 
372 		identical_pvr_fixup(node);
373 	}
374 
375 	check_cpu_feature_properties(node);
376 	check_cpu_pa_features(node);
377 	check_cpu_slb_size(node);
378 
379 #ifdef CONFIG_PPC_PSERIES
380 	if (nthreads > 1)
381 		cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
382 	else
383 		cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
384 #endif
385 
386 	return 0;
387 }
388 
389 int __init early_init_dt_scan_chosen_ppc(unsigned long node, const char *uname,
390 					 int depth, void *data)
391 {
392 	unsigned long *lprop;
393 
394 	/* Use common scan routine to determine if this is the chosen node */
395 	if (early_init_dt_scan_chosen(node, uname, depth, data) == 0)
396 		return 0;
397 
398 #ifdef CONFIG_PPC64
399 	/* check if iommu is forced on or off */
400 	if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
401 		iommu_is_off = 1;
402 	if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
403 		iommu_force_on = 1;
404 #endif
405 
406 	/* mem=x on the command line is the preferred mechanism */
407 	lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
408 	if (lprop)
409 		memory_limit = *lprop;
410 
411 #ifdef CONFIG_PPC64
412 	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
413 	if (lprop)
414 		tce_alloc_start = *lprop;
415 	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
416 	if (lprop)
417 		tce_alloc_end = *lprop;
418 #endif
419 
420 #ifdef CONFIG_KEXEC
421 	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
422 	if (lprop)
423 		crashk_res.start = *lprop;
424 
425 	lprop = of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
426 	if (lprop)
427 		crashk_res.end = crashk_res.start + *lprop - 1;
428 #endif
429 
430 	/* break now */
431 	return 1;
432 }
433 
434 #ifdef CONFIG_PPC_PSERIES
435 /*
436  * Interpret the ibm,dynamic-memory property in the
437  * /ibm,dynamic-reconfiguration-memory node.
438  * This contains a list of memory blocks along with NUMA affinity
439  * information.
440  */
441 static int __init early_init_dt_scan_drconf_memory(unsigned long node)
442 {
443 	__be32 *dm, *ls, *usm;
444 	unsigned long l, n, flags;
445 	u64 base, size, memblock_size;
446 	unsigned int is_kexec_kdump = 0, rngs;
447 
448 	ls = of_get_flat_dt_prop(node, "ibm,lmb-size", &l);
449 	if (ls == NULL || l < dt_root_size_cells * sizeof(__be32))
450 		return 0;
451 	memblock_size = dt_mem_next_cell(dt_root_size_cells, &ls);
452 
453 	dm = of_get_flat_dt_prop(node, "ibm,dynamic-memory", &l);
454 	if (dm == NULL || l < sizeof(__be32))
455 		return 0;
456 
457 	n = *dm++;	/* number of entries */
458 	if (l < (n * (dt_root_addr_cells + 4) + 1) * sizeof(__be32))
459 		return 0;
460 
461 	/* check if this is a kexec/kdump kernel. */
462 	usm = of_get_flat_dt_prop(node, "linux,drconf-usable-memory",
463 						 &l);
464 	if (usm != NULL)
465 		is_kexec_kdump = 1;
466 
467 	for (; n != 0; --n) {
468 		base = dt_mem_next_cell(dt_root_addr_cells, &dm);
469 		flags = dm[3];
470 		/* skip DRC index, pad, assoc. list index, flags */
471 		dm += 4;
472 		/* skip this block if the reserved bit is set in flags (0x80)
473 		   or if the block is not assigned to this partition (0x8) */
474 		if ((flags & 0x80) || !(flags & 0x8))
475 			continue;
476 		size = memblock_size;
477 		rngs = 1;
478 		if (is_kexec_kdump) {
479 			/*
480 			 * For each memblock in ibm,dynamic-memory, a corresponding
481 			 * entry in linux,drconf-usable-memory property contains
482 			 * a counter 'p' followed by 'p' (base, size) duple.
483 			 * Now read the counter from
484 			 * linux,drconf-usable-memory property
485 			 */
486 			rngs = dt_mem_next_cell(dt_root_size_cells, &usm);
487 			if (!rngs) /* there are no (base, size) duple */
488 				continue;
489 		}
490 		do {
491 			if (is_kexec_kdump) {
492 				base = dt_mem_next_cell(dt_root_addr_cells,
493 							 &usm);
494 				size = dt_mem_next_cell(dt_root_size_cells,
495 							 &usm);
496 			}
497 			if (iommu_is_off) {
498 				if (base >= 0x80000000ul)
499 					continue;
500 				if ((base + size) > 0x80000000ul)
501 					size = 0x80000000ul - base;
502 			}
503 			memblock_add(base, size);
504 		} while (--rngs);
505 	}
506 	memblock_dump_all();
507 	return 0;
508 }
509 #else
510 #define early_init_dt_scan_drconf_memory(node)	0
511 #endif /* CONFIG_PPC_PSERIES */
512 
513 static int __init early_init_dt_scan_memory_ppc(unsigned long node,
514 						const char *uname,
515 						int depth, void *data)
516 {
517 	if (depth == 1 &&
518 	    strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0)
519 		return early_init_dt_scan_drconf_memory(node);
520 
521 	return early_init_dt_scan_memory(node, uname, depth, data);
522 }
523 
524 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
525 {
526 #ifdef CONFIG_PPC64
527 	if (iommu_is_off) {
528 		if (base >= 0x80000000ul)
529 			return;
530 		if ((base + size) > 0x80000000ul)
531 			size = 0x80000000ul - base;
532 	}
533 #endif
534 	/* Keep track of the beginning of memory -and- the size of
535 	 * the very first block in the device-tree as it represents
536 	 * the RMA on ppc64 server
537 	 */
538 	if (base < memstart_addr) {
539 		memstart_addr = base;
540 		first_memblock_size = size;
541 	}
542 
543 	/* Add the chunk to the MEMBLOCK list */
544 	memblock_add(base, size);
545 }
546 
547 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
548 {
549 	return __va(memblock_alloc(size, align));
550 }
551 
552 #ifdef CONFIG_BLK_DEV_INITRD
553 void __init early_init_dt_setup_initrd_arch(unsigned long start,
554 		unsigned long end)
555 {
556 	initrd_start = (unsigned long)__va(start);
557 	initrd_end = (unsigned long)__va(end);
558 	initrd_below_start_ok = 1;
559 }
560 #endif
561 
562 static void __init early_reserve_mem(void)
563 {
564 	u64 base, size;
565 	u64 *reserve_map;
566 	unsigned long self_base;
567 	unsigned long self_size;
568 
569 	reserve_map = (u64 *)(((unsigned long)initial_boot_params) +
570 					initial_boot_params->off_mem_rsvmap);
571 
572 	/* before we do anything, lets reserve the dt blob */
573 	self_base = __pa((unsigned long)initial_boot_params);
574 	self_size = initial_boot_params->totalsize;
575 	memblock_reserve(self_base, self_size);
576 
577 #ifdef CONFIG_BLK_DEV_INITRD
578 	/* then reserve the initrd, if any */
579 	if (initrd_start && (initrd_end > initrd_start))
580 		memblock_reserve(_ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
581 			_ALIGN_UP(initrd_end, PAGE_SIZE) -
582 			_ALIGN_DOWN(initrd_start, PAGE_SIZE));
583 #endif /* CONFIG_BLK_DEV_INITRD */
584 
585 #ifdef CONFIG_PPC32
586 	/*
587 	 * Handle the case where we might be booting from an old kexec
588 	 * image that setup the mem_rsvmap as pairs of 32-bit values
589 	 */
590 	if (*reserve_map > 0xffffffffull) {
591 		u32 base_32, size_32;
592 		u32 *reserve_map_32 = (u32 *)reserve_map;
593 
594 		while (1) {
595 			base_32 = *(reserve_map_32++);
596 			size_32 = *(reserve_map_32++);
597 			if (size_32 == 0)
598 				break;
599 			/* skip if the reservation is for the blob */
600 			if (base_32 == self_base && size_32 == self_size)
601 				continue;
602 			DBG("reserving: %x -> %x\n", base_32, size_32);
603 			memblock_reserve(base_32, size_32);
604 		}
605 		return;
606 	}
607 #endif
608 	while (1) {
609 		base = *(reserve_map++);
610 		size = *(reserve_map++);
611 		if (size == 0)
612 			break;
613 		DBG("reserving: %llx -> %llx\n", base, size);
614 		memblock_reserve(base, size);
615 	}
616 }
617 
618 void __init early_init_devtree(void *params)
619 {
620 	phys_addr_t limit;
621 
622 	DBG(" -> early_init_devtree(%p)\n", params);
623 
624 	/* Setup flat device-tree pointer */
625 	initial_boot_params = params;
626 
627 #ifdef CONFIG_PPC_RTAS
628 	/* Some machines might need RTAS info for debugging, grab it now. */
629 	of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
630 #endif
631 
632 #ifdef CONFIG_PPC_POWERNV
633 	/* Some machines might need OPAL info for debugging, grab it now. */
634 	of_scan_flat_dt(early_init_dt_scan_opal, NULL);
635 #endif
636 
637 #ifdef CONFIG_FA_DUMP
638 	/* scan tree to see if dump is active during last boot */
639 	of_scan_flat_dt(early_init_dt_scan_fw_dump, NULL);
640 #endif
641 
642 	/* Pre-initialize the cmd_line with the content of boot_commmand_line,
643 	 * which will be empty except when the content of the variable has
644 	 * been overriden by a bootloading mechanism. This happens typically
645 	 * with HAL takeover
646 	 */
647 	strlcpy(cmd_line, boot_command_line, COMMAND_LINE_SIZE);
648 
649 	/* Retrieve various informations from the /chosen node of the
650 	 * device-tree, including the platform type, initrd location and
651 	 * size, TCE reserve, and more ...
652 	 */
653 	of_scan_flat_dt(early_init_dt_scan_chosen_ppc, cmd_line);
654 
655 	/* Scan memory nodes and rebuild MEMBLOCKs */
656 	of_scan_flat_dt(early_init_dt_scan_root, NULL);
657 	of_scan_flat_dt(early_init_dt_scan_memory_ppc, NULL);
658 
659 	/* Save command line for /proc/cmdline and then parse parameters */
660 	strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE);
661 	parse_early_param();
662 
663 	/* make sure we've parsed cmdline for mem= before this */
664 	if (memory_limit)
665 		first_memblock_size = min(first_memblock_size, memory_limit);
666 	setup_initial_memory_limit(memstart_addr, first_memblock_size);
667 	/* Reserve MEMBLOCK regions used by kernel, initrd, dt, etc... */
668 	memblock_reserve(PHYSICAL_START, __pa(klimit) - PHYSICAL_START);
669 	/* If relocatable, reserve first 32k for interrupt vectors etc. */
670 	if (PHYSICAL_START > MEMORY_START)
671 		memblock_reserve(MEMORY_START, 0x8000);
672 	reserve_kdump_trampoline();
673 #ifdef CONFIG_FA_DUMP
674 	/*
675 	 * If we fail to reserve memory for firmware-assisted dump then
676 	 * fallback to kexec based kdump.
677 	 */
678 	if (fadump_reserve_mem() == 0)
679 #endif
680 		reserve_crashkernel();
681 	early_reserve_mem();
682 
683 	/*
684 	 * Ensure that total memory size is page-aligned, because otherwise
685 	 * mark_bootmem() gets upset.
686 	 */
687 	limit = ALIGN(memory_limit ?: memblock_phys_mem_size(), PAGE_SIZE);
688 	memblock_enforce_memory_limit(limit);
689 
690 	memblock_allow_resize();
691 	memblock_dump_all();
692 
693 	DBG("Phys. mem: %llx\n", memblock_phys_mem_size());
694 
695 	/* We may need to relocate the flat tree, do it now.
696 	 * FIXME .. and the initrd too? */
697 	move_device_tree();
698 
699 	allocate_pacas();
700 
701 	DBG("Scanning CPUs ...\n");
702 
703 	/* Retrieve CPU related informations from the flat tree
704 	 * (altivec support, boot CPU ID, ...)
705 	 */
706 	of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
707 
708 #if defined(CONFIG_SMP) && defined(CONFIG_PPC64)
709 	/* We'll later wait for secondaries to check in; there are
710 	 * NCPUS-1 non-boot CPUs  :-)
711 	 */
712 	spinning_secondaries = boot_cpu_count - 1;
713 #endif
714 
715 	DBG(" <- early_init_devtree()\n");
716 }
717 
718 /*******
719  *
720  * New implementation of the OF "find" APIs, return a refcounted
721  * object, call of_node_put() when done.  The device tree and list
722  * are protected by a rw_lock.
723  *
724  * Note that property management will need some locking as well,
725  * this isn't dealt with yet.
726  *
727  *******/
728 
729 /**
730  *	of_find_next_cache_node - Find a node's subsidiary cache
731  *	@np:	node of type "cpu" or "cache"
732  *
733  *	Returns a node pointer with refcount incremented, use
734  *	of_node_put() on it when done.  Caller should hold a reference
735  *	to np.
736  */
737 struct device_node *of_find_next_cache_node(struct device_node *np)
738 {
739 	struct device_node *child;
740 	const phandle *handle;
741 
742 	handle = of_get_property(np, "l2-cache", NULL);
743 	if (!handle)
744 		handle = of_get_property(np, "next-level-cache", NULL);
745 
746 	if (handle)
747 		return of_find_node_by_phandle(*handle);
748 
749 	/* OF on pmac has nodes instead of properties named "l2-cache"
750 	 * beneath CPU nodes.
751 	 */
752 	if (!strcmp(np->type, "cpu"))
753 		for_each_child_of_node(np, child)
754 			if (!strcmp(child->type, "cache"))
755 				return child;
756 
757 	return NULL;
758 }
759 
760 #ifdef CONFIG_PPC_PSERIES
761 /*
762  * Fix up the uninitialized fields in a new device node:
763  * name, type and pci-specific fields
764  */
765 
766 static int of_finish_dynamic_node(struct device_node *node)
767 {
768 	struct device_node *parent = of_get_parent(node);
769 	int err = 0;
770 	const phandle *ibm_phandle;
771 
772 	node->name = of_get_property(node, "name", NULL);
773 	node->type = of_get_property(node, "device_type", NULL);
774 
775 	if (!node->name)
776 		node->name = "<NULL>";
777 	if (!node->type)
778 		node->type = "<NULL>";
779 
780 	if (!parent) {
781 		err = -ENODEV;
782 		goto out;
783 	}
784 
785 	/* We don't support that function on PowerMac, at least
786 	 * not yet
787 	 */
788 	if (machine_is(powermac))
789 		return -ENODEV;
790 
791 	/* fix up new node's phandle field */
792 	if ((ibm_phandle = of_get_property(node, "ibm,phandle", NULL)))
793 		node->phandle = *ibm_phandle;
794 
795 out:
796 	of_node_put(parent);
797 	return err;
798 }
799 
800 static int prom_reconfig_notifier(struct notifier_block *nb,
801 				  unsigned long action, void *node)
802 {
803 	int err;
804 
805 	switch (action) {
806 	case PSERIES_RECONFIG_ADD:
807 		err = of_finish_dynamic_node(node);
808 		if (err < 0)
809 			printk(KERN_ERR "finish_node returned %d\n", err);
810 		break;
811 	default:
812 		err = 0;
813 		break;
814 	}
815 	return notifier_from_errno(err);
816 }
817 
818 static struct notifier_block prom_reconfig_nb = {
819 	.notifier_call = prom_reconfig_notifier,
820 	.priority = 10, /* This one needs to run first */
821 };
822 
823 static int __init prom_reconfig_setup(void)
824 {
825 	return pSeries_reconfig_notifier_register(&prom_reconfig_nb);
826 }
827 __initcall(prom_reconfig_setup);
828 #endif
829 
830 /* Find the device node for a given logical cpu number, also returns the cpu
831  * local thread number (index in ibm,interrupt-server#s) if relevant and
832  * asked for (non NULL)
833  */
834 struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
835 {
836 	int hardid;
837 	struct device_node *np;
838 
839 	hardid = get_hard_smp_processor_id(cpu);
840 
841 	for_each_node_by_type(np, "cpu") {
842 		const u32 *intserv;
843 		unsigned int plen, t;
844 
845 		/* Check for ibm,ppc-interrupt-server#s. If it doesn't exist
846 		 * fallback to "reg" property and assume no threads
847 		 */
848 		intserv = of_get_property(np, "ibm,ppc-interrupt-server#s",
849 				&plen);
850 		if (intserv == NULL) {
851 			const u32 *reg = of_get_property(np, "reg", NULL);
852 			if (reg == NULL)
853 				continue;
854 			if (*reg == hardid) {
855 				if (thread)
856 					*thread = 0;
857 				return np;
858 			}
859 		} else {
860 			plen /= sizeof(u32);
861 			for (t = 0; t < plen; t++) {
862 				if (hardid == intserv[t]) {
863 					if (thread)
864 						*thread = t;
865 					return np;
866 				}
867 			}
868 		}
869 	}
870 	return NULL;
871 }
872 EXPORT_SYMBOL(of_get_cpu_node);
873 
874 #if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
875 static struct debugfs_blob_wrapper flat_dt_blob;
876 
877 static int __init export_flat_device_tree(void)
878 {
879 	struct dentry *d;
880 
881 	flat_dt_blob.data = initial_boot_params;
882 	flat_dt_blob.size = initial_boot_params->totalsize;
883 
884 	d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR,
885 				powerpc_debugfs_root, &flat_dt_blob);
886 	if (!d)
887 		return 1;
888 
889 	return 0;
890 }
891 __initcall(export_flat_device_tree);
892 #endif
893