2 * Procedures for creating, accessing and interpreting the device tree.
4 * Paul Mackerras August 1996.
5 * Copyright (C) 1996-2005 Paul Mackerras.
7 * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
8 * {engebret|bergner}@us.ibm.com
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.
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/module.h>
31 #include <linux/kexec.h>
32 #include <linux/debugfs.h>
33 #include <linux/irq.h>
34 #include <linux/lmb.h>
39 #include <asm/processor.h>
42 #include <asm/kdump.h>
44 #include <asm/system.h>
46 #include <asm/pgtable.h>
48 #include <asm/iommu.h>
49 #include <asm/btext.h>
50 #include <asm/sections.h>
51 #include <asm/machdep.h>
52 #include <asm/pSeries_reconfig.h>
53 #include <asm/pci-bridge.h>
54 #include <asm/phyp_dump.h>
55 #include <asm/kexec.h>
56 #include <mm/mmu_decl.h>
59 #define DBG(fmt...) printk(KERN_ERR fmt)
65 static int __initdata dt_root_addr_cells;
66 static int __initdata dt_root_size_cells;
69 int __initdata iommu_is_off;
70 int __initdata iommu_force_on;
71 unsigned long tce_alloc_start, tce_alloc_end;
77 static struct boot_param_header *initial_boot_params __initdata;
79 struct boot_param_header *initial_boot_params;
82 extern struct device_node *allnodes; /* temporary while merging */
84 extern rwlock_t devtree_lock; /* temporary while merging */
86 /* export that to outside world */
87 struct device_node *of_chosen;
89 static inline char *find_flat_dt_string(u32 offset)
91 return ((char *)initial_boot_params) +
92 initial_boot_params->off_dt_strings + offset;
96 * This function is used to scan the flattened device-tree, it is
97 * used to extract the memory informations at boot before we can
100 int __init of_scan_flat_dt(int (*it)(unsigned long node,
101 const char *uname, int depth,
105 unsigned long p = ((unsigned long)initial_boot_params) +
106 initial_boot_params->off_dt_struct;
111 u32 tag = *((u32 *)p);
115 if (tag == OF_DT_END_NODE) {
119 if (tag == OF_DT_NOP)
121 if (tag == OF_DT_END)
123 if (tag == OF_DT_PROP) {
124 u32 sz = *((u32 *)p);
126 if (initial_boot_params->version < 0x10)
127 p = _ALIGN(p, sz >= 8 ? 8 : 4);
132 if (tag != OF_DT_BEGIN_NODE) {
133 printk(KERN_WARNING "Invalid tag %x scanning flattened"
134 " device tree !\n", tag);
139 p = _ALIGN(p + strlen(pathp) + 1, 4);
140 if ((*pathp) == '/') {
142 for (lp = NULL, np = pathp; *np; np++)
148 rc = it(p, pathp, depth, data);
156 unsigned long __init of_get_flat_dt_root(void)
158 unsigned long p = ((unsigned long)initial_boot_params) +
159 initial_boot_params->off_dt_struct;
161 while(*((u32 *)p) == OF_DT_NOP)
163 BUG_ON (*((u32 *)p) != OF_DT_BEGIN_NODE);
165 return _ALIGN(p + strlen((char *)p) + 1, 4);
169 * This function can be used within scan_flattened_dt callback to get
170 * access to properties
172 void* __init of_get_flat_dt_prop(unsigned long node, const char *name,
175 unsigned long p = node;
178 u32 tag = *((u32 *)p);
183 if (tag == OF_DT_NOP)
185 if (tag != OF_DT_PROP)
189 noff = *((u32 *)(p + 4));
191 if (initial_boot_params->version < 0x10)
192 p = _ALIGN(p, sz >= 8 ? 8 : 4);
194 nstr = find_flat_dt_string(noff);
196 printk(KERN_WARNING "Can't find property index"
200 if (strcmp(name, nstr) == 0) {
210 int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
213 unsigned long cplen, l;
215 cp = of_get_flat_dt_prop(node, "compatible", &cplen);
219 if (strncasecmp(cp, compat, strlen(compat)) == 0)
229 static void *__init unflatten_dt_alloc(unsigned long *mem, unsigned long size,
234 *mem = _ALIGN(*mem, align);
241 static unsigned long __init unflatten_dt_node(unsigned long mem,
243 struct device_node *dad,
244 struct device_node ***allnextpp,
245 unsigned long fpsize)
247 struct device_node *np;
248 struct property *pp, **prev_pp = NULL;
251 unsigned int l, allocl;
255 tag = *((u32 *)(*p));
256 if (tag != OF_DT_BEGIN_NODE) {
257 printk("Weird tag at start of node: %x\n", tag);
262 l = allocl = strlen(pathp) + 1;
263 *p = _ALIGN(*p + l, 4);
265 /* version 0x10 has a more compact unit name here instead of the full
266 * path. we accumulate the full path size using "fpsize", we'll rebuild
267 * it later. We detect this because the first character of the name is
270 if ((*pathp) != '/') {
273 /* root node: special case. fpsize accounts for path
274 * plus terminating zero. root node only has '/', so
275 * fpsize should be 2, but we want to avoid the first
276 * level nodes to have two '/' so we use fpsize 1 here
281 /* account for '/' and path size minus terminal 0
290 np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
291 __alignof__(struct device_node));
293 memset(np, 0, sizeof(*np));
294 np->full_name = ((char*)np) + sizeof(struct device_node);
296 char *p = np->full_name;
297 /* rebuild full path for new format */
298 if (dad && dad->parent) {
299 strcpy(p, dad->full_name);
301 if ((strlen(p) + l + 1) != allocl) {
302 DBG("%s: p: %d, l: %d, a: %d\n",
303 pathp, (int)strlen(p), l, allocl);
311 memcpy(np->full_name, pathp, l);
312 prev_pp = &np->properties;
314 *allnextpp = &np->allnext;
317 /* we temporarily use the next field as `last_child'*/
321 dad->next->sibling = np;
324 kref_init(&np->kref);
330 tag = *((u32 *)(*p));
331 if (tag == OF_DT_NOP) {
335 if (tag != OF_DT_PROP)
339 noff = *((u32 *)((*p) + 4));
341 if (initial_boot_params->version < 0x10)
342 *p = _ALIGN(*p, sz >= 8 ? 8 : 4);
344 pname = find_flat_dt_string(noff);
346 printk("Can't find property name in list !\n");
349 if (strcmp(pname, "name") == 0)
351 l = strlen(pname) + 1;
352 pp = unflatten_dt_alloc(&mem, sizeof(struct property),
353 __alignof__(struct property));
355 if (strcmp(pname, "linux,phandle") == 0) {
356 np->node = *((u32 *)*p);
357 if (np->linux_phandle == 0)
358 np->linux_phandle = np->node;
360 if (strcmp(pname, "ibm,phandle") == 0)
361 np->linux_phandle = *((u32 *)*p);
364 pp->value = (void *)*p;
368 *p = _ALIGN((*p) + sz, 4);
370 /* with version 0x10 we may not have the name property, recreate
371 * it here from the unit name if absent
374 char *p = pathp, *ps = pathp, *pa = NULL;
387 pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
388 __alignof__(struct property));
395 memcpy(pp->value, ps, sz - 1);
396 ((char *)pp->value)[sz - 1] = 0;
397 DBG("fixed up name for %s -> %s\n", pathp,
403 np->name = of_get_property(np, "name", NULL);
404 np->type = of_get_property(np, "device_type", NULL);
411 while (tag == OF_DT_BEGIN_NODE) {
412 mem = unflatten_dt_node(mem, p, np, allnextpp, fpsize);
413 tag = *((u32 *)(*p));
415 if (tag != OF_DT_END_NODE) {
416 printk("Weird tag at end of node: %x\n", tag);
423 static int __init early_parse_mem(char *p)
428 memory_limit = PAGE_ALIGN(memparse(p, &p));
429 DBG("memory limit = 0x%lx\n", memory_limit);
433 early_param("mem", early_parse_mem);
436 * move_device_tree - move tree to an unused area, if needed.
438 * The device tree may be allocated beyond our memory limit, or inside the
439 * crash kernel region for kdump. If so, move it out of the way.
441 static void __init move_device_tree(void)
443 unsigned long start, size;
446 DBG("-> move_device_tree\n");
448 start = __pa(initial_boot_params);
449 size = initial_boot_params->totalsize;
451 if ((memory_limit && (start + size) > memory_limit) ||
452 overlaps_crashkernel(start, size)) {
453 p = __va(lmb_alloc_base(size, PAGE_SIZE, lmb.rmo_size));
454 memcpy(p, initial_boot_params, size);
455 initial_boot_params = (struct boot_param_header *)p;
456 DBG("Moved device tree to 0x%p\n", p);
459 DBG("<- move_device_tree\n");
463 * unflattens the device-tree passed by the firmware, creating the
464 * tree of struct device_node. It also fills the "name" and "type"
465 * pointers of the nodes so the normal device-tree walking functions
466 * can be used (this used to be done by finish_device_tree)
468 void __init unflatten_device_tree(void)
470 unsigned long start, mem, size;
471 struct device_node **allnextp = &allnodes;
473 DBG(" -> unflatten_device_tree()\n");
475 /* First pass, scan for size */
476 start = ((unsigned long)initial_boot_params) +
477 initial_boot_params->off_dt_struct;
478 size = unflatten_dt_node(0, &start, NULL, NULL, 0);
479 size = (size | 3) + 1;
481 DBG(" size is %lx, allocating...\n", size);
483 /* Allocate memory for the expanded device tree */
484 mem = lmb_alloc(size + 4, __alignof__(struct device_node));
485 mem = (unsigned long) __va(mem);
487 ((u32 *)mem)[size / 4] = 0xdeadbeef;
489 DBG(" unflattening %lx...\n", mem);
491 /* Second pass, do actual unflattening */
492 start = ((unsigned long)initial_boot_params) +
493 initial_boot_params->off_dt_struct;
494 unflatten_dt_node(mem, &start, NULL, &allnextp, 0);
495 if (*((u32 *)start) != OF_DT_END)
496 printk(KERN_WARNING "Weird tag at end of tree: %08x\n", *((u32 *)start));
497 if (((u32 *)mem)[size / 4] != 0xdeadbeef)
498 printk(KERN_WARNING "End of tree marker overwritten: %08x\n",
499 ((u32 *)mem)[size / 4] );
502 /* Get pointer to OF "/chosen" node for use everywhere */
503 of_chosen = of_find_node_by_path("/chosen");
504 if (of_chosen == NULL)
505 of_chosen = of_find_node_by_path("/chosen@0");
507 DBG(" <- unflatten_device_tree()\n");
511 * ibm,pa-features is a per-cpu property that contains a string of
512 * attribute descriptors, each of which has a 2 byte header plus up
513 * to 254 bytes worth of processor attribute bits. First header
514 * byte specifies the number of bytes following the header.
515 * Second header byte is an "attribute-specifier" type, of which
516 * zero is the only currently-defined value.
517 * Implementation: Pass in the byte and bit offset for the feature
518 * that we are interested in. The function will return -1 if the
519 * pa-features property is missing, or a 1/0 to indicate if the feature
520 * is supported/not supported. Note that the bit numbers are
521 * big-endian to match the definition in PAPR.
523 static struct ibm_pa_feature {
524 unsigned long cpu_features; /* CPU_FTR_xxx bit */
525 unsigned int cpu_user_ftrs; /* PPC_FEATURE_xxx bit */
526 unsigned char pabyte; /* byte number in ibm,pa-features */
527 unsigned char pabit; /* bit number (big-endian) */
528 unsigned char invert; /* if 1, pa bit set => clear feature */
529 } ibm_pa_features[] __initdata = {
530 {0, PPC_FEATURE_HAS_MMU, 0, 0, 0},
531 {0, PPC_FEATURE_HAS_FPU, 0, 1, 0},
532 {CPU_FTR_SLB, 0, 0, 2, 0},
533 {CPU_FTR_CTRL, 0, 0, 3, 0},
534 {CPU_FTR_NOEXECUTE, 0, 0, 6, 0},
535 {CPU_FTR_NODSISRALIGN, 0, 1, 1, 1},
536 {CPU_FTR_CI_LARGE_PAGE, 0, 1, 2, 0},
537 {CPU_FTR_REAL_LE, PPC_FEATURE_TRUE_LE, 5, 0, 0},
540 static void __init scan_features(unsigned long node, unsigned char *ftrs,
541 unsigned long tablelen,
542 struct ibm_pa_feature *fp,
543 unsigned long ft_size)
545 unsigned long i, len, bit;
547 /* find descriptor with type == 0 */
553 return; /* descriptor 0 not found */
560 /* loop over bits we know about */
561 for (i = 0; i < ft_size; ++i, ++fp) {
562 if (fp->pabyte >= ftrs[0])
564 bit = (ftrs[2 + fp->pabyte] >> (7 - fp->pabit)) & 1;
565 if (bit ^ fp->invert) {
566 cur_cpu_spec->cpu_features |= fp->cpu_features;
567 cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftrs;
569 cur_cpu_spec->cpu_features &= ~fp->cpu_features;
570 cur_cpu_spec->cpu_user_features &= ~fp->cpu_user_ftrs;
575 static void __init check_cpu_pa_features(unsigned long node)
577 unsigned char *pa_ftrs;
578 unsigned long tablelen;
580 pa_ftrs = of_get_flat_dt_prop(node, "ibm,pa-features", &tablelen);
584 scan_features(node, pa_ftrs, tablelen,
585 ibm_pa_features, ARRAY_SIZE(ibm_pa_features));
589 static void __init check_cpu_slb_size(unsigned long node)
593 slb_size_ptr = of_get_flat_dt_prop(node, "slb-size", NULL);
594 if (slb_size_ptr != NULL) {
595 mmu_slb_size = *slb_size_ptr;
598 slb_size_ptr = of_get_flat_dt_prop(node, "ibm,slb-size", NULL);
599 if (slb_size_ptr != NULL) {
600 mmu_slb_size = *slb_size_ptr;
604 #define check_cpu_slb_size(node) do { } while(0)
607 static struct feature_property {
610 unsigned long cpu_feature;
611 unsigned long cpu_user_ftr;
612 } feature_properties[] __initdata = {
613 #ifdef CONFIG_ALTIVEC
614 {"altivec", 0, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
615 {"ibm,vmx", 1, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
616 #endif /* CONFIG_ALTIVEC */
618 /* Yes, this _really_ is ibm,vmx == 2 to enable VSX */
619 {"ibm,vmx", 2, CPU_FTR_VSX, PPC_FEATURE_HAS_VSX},
620 #endif /* CONFIG_VSX */
622 {"ibm,dfp", 1, 0, PPC_FEATURE_HAS_DFP},
623 {"ibm,purr", 1, CPU_FTR_PURR, 0},
624 {"ibm,spurr", 1, CPU_FTR_SPURR, 0},
625 #endif /* CONFIG_PPC64 */
628 #if defined(CONFIG_44x) && defined(CONFIG_PPC_FPU)
629 static inline void identical_pvr_fixup(unsigned long node)
632 char *model = of_get_flat_dt_prop(node, "model", NULL);
635 * Since 440GR(x)/440EP(x) processors have the same pvr,
636 * we check the node path and set bit 28 in the cur_cpu_spec
637 * pvr for EP(x) processor version. This bit is always 0 in
638 * the "real" pvr. Then we call identify_cpu again with
639 * the new logical pvr to enable FPU support.
641 if (model && strstr(model, "440EP")) {
642 pvr = cur_cpu_spec->pvr_value | 0x8;
643 identify_cpu(0, pvr);
644 DBG("Using logical pvr %x for %s\n", pvr, model);
648 #define identical_pvr_fixup(node) do { } while(0)
651 static void __init check_cpu_feature_properties(unsigned long node)
654 struct feature_property *fp = feature_properties;
657 for (i = 0; i < ARRAY_SIZE(feature_properties); ++i, ++fp) {
658 prop = of_get_flat_dt_prop(node, fp->name, NULL);
659 if (prop && *prop >= fp->min_value) {
660 cur_cpu_spec->cpu_features |= fp->cpu_feature;
661 cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftr;
666 static int __init early_init_dt_scan_cpus(unsigned long node,
667 const char *uname, int depth,
670 static int logical_cpuid = 0;
671 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
678 /* We are scanning "cpu" nodes only */
679 if (type == NULL || strcmp(type, "cpu") != 0)
682 /* Get physical cpuid */
683 intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
685 nthreads = len / sizeof(int);
687 intserv = of_get_flat_dt_prop(node, "reg", NULL);
692 * Now see if any of these threads match our boot cpu.
693 * NOTE: This must match the parsing done in smp_setup_cpu_maps.
695 for (i = 0; i < nthreads; i++) {
697 * version 2 of the kexec param format adds the phys cpuid of
700 if (initial_boot_params && initial_boot_params->version >= 2) {
702 initial_boot_params->boot_cpuid_phys) {
708 * Check if it's the boot-cpu, set it's hw index now,
709 * unfortunately this format did not support booting
710 * off secondary threads.
712 if (of_get_flat_dt_prop(node,
713 "linux,boot-cpu", NULL) != NULL) {
720 /* logical cpu id is always 0 on UP kernels */
726 DBG("boot cpu: logical %d physical %d\n", logical_cpuid,
728 boot_cpuid = logical_cpuid;
729 set_hard_smp_processor_id(boot_cpuid, intserv[i]);
732 * PAPR defines "logical" PVR values for cpus that
733 * meet various levels of the architecture:
734 * 0x0f000001 Architecture version 2.04
735 * 0x0f000002 Architecture version 2.05
736 * If the cpu-version property in the cpu node contains
737 * such a value, we call identify_cpu again with the
738 * logical PVR value in order to use the cpu feature
739 * bits appropriate for the architecture level.
741 * A POWER6 partition in "POWER6 architected" mode
742 * uses the 0x0f000002 PVR value; in POWER5+ mode
743 * it uses 0x0f000001.
745 prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
746 if (prop && (*prop & 0xff000000) == 0x0f000000)
747 identify_cpu(0, *prop);
749 identical_pvr_fixup(node);
752 check_cpu_feature_properties(node);
753 check_cpu_pa_features(node);
754 check_cpu_slb_size(node);
756 #ifdef CONFIG_PPC_PSERIES
758 cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
760 cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
766 #ifdef CONFIG_BLK_DEV_INITRD
767 static void __init early_init_dt_check_for_initrd(unsigned long node)
772 DBG("Looking for initrd properties... ");
774 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &l);
776 initrd_start = (unsigned long)__va(of_read_ulong(prop, l/4));
778 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &l);
780 initrd_end = (unsigned long)
781 __va(of_read_ulong(prop, l/4));
782 initrd_below_start_ok = 1;
788 DBG("initrd_start=0x%lx initrd_end=0x%lx\n", initrd_start, initrd_end);
791 static inline void early_init_dt_check_for_initrd(unsigned long node)
794 #endif /* CONFIG_BLK_DEV_INITRD */
796 static int __init early_init_dt_scan_chosen(unsigned long node,
797 const char *uname, int depth, void *data)
799 unsigned long *lprop;
803 DBG("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
806 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
810 /* check if iommu is forced on or off */
811 if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
813 if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
817 /* mem=x on the command line is the preferred mechanism */
818 lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
820 memory_limit = *lprop;
823 lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
825 tce_alloc_start = *lprop;
826 lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
828 tce_alloc_end = *lprop;
832 lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
834 crashk_res.start = *lprop;
836 lprop = of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
838 crashk_res.end = crashk_res.start + *lprop - 1;
841 early_init_dt_check_for_initrd(node);
843 /* Retreive command line */
844 p = of_get_flat_dt_prop(node, "bootargs", &l);
845 if (p != NULL && l > 0)
846 strlcpy(cmd_line, p, min((int)l, COMMAND_LINE_SIZE));
848 #ifdef CONFIG_CMDLINE
849 if (p == NULL || l == 0 || (l == 1 && (*p) == 0))
850 strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
851 #endif /* CONFIG_CMDLINE */
853 DBG("Command line is: %s\n", cmd_line);
859 static int __init early_init_dt_scan_root(unsigned long node,
860 const char *uname, int depth, void *data)
867 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
868 dt_root_size_cells = (prop == NULL) ? 1 : *prop;
869 DBG("dt_root_size_cells = %x\n", dt_root_size_cells);
871 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
872 dt_root_addr_cells = (prop == NULL) ? 2 : *prop;
873 DBG("dt_root_addr_cells = %x\n", dt_root_addr_cells);
879 static u64 __init dt_mem_next_cell(int s, cell_t **cellp)
884 return of_read_number(p, s);
887 #ifdef CONFIG_PPC_PSERIES
889 * Interpret the ibm,dynamic-memory property in the
890 * /ibm,dynamic-reconfiguration-memory node.
891 * This contains a list of memory blocks along with NUMA affinity
894 static int __init early_init_dt_scan_drconf_memory(unsigned long node)
896 cell_t *dm, *ls, *usm;
897 unsigned long l, n, flags;
898 u64 base, size, lmb_size;
899 unsigned int is_kexec_kdump = 0, rngs;
901 ls = of_get_flat_dt_prop(node, "ibm,lmb-size", &l);
902 if (ls == NULL || l < dt_root_size_cells * sizeof(cell_t))
904 lmb_size = dt_mem_next_cell(dt_root_size_cells, &ls);
906 dm = of_get_flat_dt_prop(node, "ibm,dynamic-memory", &l);
907 if (dm == NULL || l < sizeof(cell_t))
910 n = *dm++; /* number of entries */
911 if (l < (n * (dt_root_addr_cells + 4) + 1) * sizeof(cell_t))
914 /* check if this is a kexec/kdump kernel. */
915 usm = of_get_flat_dt_prop(node, "linux,drconf-usable-memory",
920 for (; n != 0; --n) {
921 base = dt_mem_next_cell(dt_root_addr_cells, &dm);
923 /* skip DRC index, pad, assoc. list index, flags */
925 /* skip this block if the reserved bit is set in flags (0x80)
926 or if the block is not assigned to this partition (0x8) */
927 if ((flags & 0x80) || !(flags & 0x8))
931 if (is_kexec_kdump) {
933 * For each lmb in ibm,dynamic-memory, a corresponding
934 * entry in linux,drconf-usable-memory property contains
935 * a counter 'p' followed by 'p' (base, size) duple.
936 * Now read the counter from
937 * linux,drconf-usable-memory property
939 rngs = dt_mem_next_cell(dt_root_size_cells, &usm);
940 if (!rngs) /* there are no (base, size) duple */
944 if (is_kexec_kdump) {
945 base = dt_mem_next_cell(dt_root_addr_cells,
947 size = dt_mem_next_cell(dt_root_size_cells,
951 if (base >= 0x80000000ul)
953 if ((base + size) > 0x80000000ul)
954 size = 0x80000000ul - base;
963 #define early_init_dt_scan_drconf_memory(node) 0
964 #endif /* CONFIG_PPC_PSERIES */
966 static int __init early_init_dt_scan_memory(unsigned long node,
967 const char *uname, int depth, void *data)
969 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
973 /* Look for the ibm,dynamic-reconfiguration-memory node */
975 strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0)
976 return early_init_dt_scan_drconf_memory(node);
978 /* We are scanning "memory" nodes only */
981 * The longtrail doesn't have a device_type on the
982 * /memory node, so look for the node called /memory@0.
984 if (depth != 1 || strcmp(uname, "memory@0") != 0)
986 } else if (strcmp(type, "memory") != 0)
989 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
991 reg = of_get_flat_dt_prop(node, "reg", &l);
995 endp = reg + (l / sizeof(cell_t));
997 DBG("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
998 uname, l, reg[0], reg[1], reg[2], reg[3]);
1000 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
1003 base = dt_mem_next_cell(dt_root_addr_cells, ®);
1004 size = dt_mem_next_cell(dt_root_size_cells, ®);
1008 DBG(" - %llx , %llx\n", (unsigned long long)base,
1009 (unsigned long long)size);
1012 if (base >= 0x80000000ul)
1014 if ((base + size) > 0x80000000ul)
1015 size = 0x80000000ul - base;
1018 lmb_add(base, size);
1020 memstart_addr = min((u64)memstart_addr, base);
1026 static void __init early_reserve_mem(void)
1030 unsigned long self_base;
1031 unsigned long self_size;
1033 reserve_map = (u64 *)(((unsigned long)initial_boot_params) +
1034 initial_boot_params->off_mem_rsvmap);
1036 /* before we do anything, lets reserve the dt blob */
1037 self_base = __pa((unsigned long)initial_boot_params);
1038 self_size = initial_boot_params->totalsize;
1039 lmb_reserve(self_base, self_size);
1041 #ifdef CONFIG_BLK_DEV_INITRD
1042 /* then reserve the initrd, if any */
1043 if (initrd_start && (initrd_end > initrd_start))
1044 lmb_reserve(__pa(initrd_start), initrd_end - initrd_start);
1045 #endif /* CONFIG_BLK_DEV_INITRD */
1049 * Handle the case where we might be booting from an old kexec
1050 * image that setup the mem_rsvmap as pairs of 32-bit values
1052 if (*reserve_map > 0xffffffffull) {
1053 u32 base_32, size_32;
1054 u32 *reserve_map_32 = (u32 *)reserve_map;
1057 base_32 = *(reserve_map_32++);
1058 size_32 = *(reserve_map_32++);
1061 /* skip if the reservation is for the blob */
1062 if (base_32 == self_base && size_32 == self_size)
1064 DBG("reserving: %x -> %x\n", base_32, size_32);
1065 lmb_reserve(base_32, size_32);
1071 base = *(reserve_map++);
1072 size = *(reserve_map++);
1075 DBG("reserving: %llx -> %llx\n", base, size);
1076 lmb_reserve(base, size);
1080 DBG("memory reserved, lmbs :\n");
1085 #ifdef CONFIG_PHYP_DUMP
1087 * phyp_dump_calculate_reserve_size() - reserve variable boot area 5% or arg
1089 * Function to find the largest size we need to reserve
1090 * during early boot process.
1092 * It either looks for boot param and returns that OR
1093 * returns larger of 256 or 5% rounded down to multiples of 256MB.
1096 static inline unsigned long phyp_dump_calculate_reserve_size(void)
1100 if (phyp_dump_info->reserve_bootvar)
1101 return phyp_dump_info->reserve_bootvar;
1103 /* divide by 20 to get 5% of value */
1104 tmp = lmb_end_of_DRAM();
1107 /* round it down in multiples of 256 */
1108 tmp = tmp & ~0x0FFFFFFFUL;
1110 return (tmp > PHYP_DUMP_RMR_END ? tmp : PHYP_DUMP_RMR_END);
1114 * phyp_dump_reserve_mem() - reserve all not-yet-dumped mmemory
1116 * This routine may reserve memory regions in the kernel only
1117 * if the system is supported and a dump was taken in last
1118 * boot instance or if the hardware is supported and the
1119 * scratch area needs to be setup. In other instances it returns
1120 * without reserving anything. The memory in case of dump being
1121 * active is freed when the dump is collected (by userland tools).
1123 static void __init phyp_dump_reserve_mem(void)
1125 unsigned long base, size;
1126 unsigned long variable_reserve_size;
1128 if (!phyp_dump_info->phyp_dump_configured) {
1129 printk(KERN_ERR "Phyp-dump not supported on this hardware\n");
1133 if (!phyp_dump_info->phyp_dump_at_boot) {
1134 printk(KERN_INFO "Phyp-dump disabled at boot time\n");
1138 variable_reserve_size = phyp_dump_calculate_reserve_size();
1140 if (phyp_dump_info->phyp_dump_is_active) {
1141 /* Reserve *everything* above RMR.Area freed by userland tools*/
1142 base = variable_reserve_size;
1143 size = lmb_end_of_DRAM() - base;
1145 /* XXX crashed_ram_end is wrong, since it may be beyond
1146 * the memory_limit, it will need to be adjusted. */
1147 lmb_reserve(base, size);
1149 phyp_dump_info->init_reserve_start = base;
1150 phyp_dump_info->init_reserve_size = size;
1152 size = phyp_dump_info->cpu_state_size +
1153 phyp_dump_info->hpte_region_size +
1154 variable_reserve_size;
1155 base = lmb_end_of_DRAM() - size;
1156 lmb_reserve(base, size);
1157 phyp_dump_info->init_reserve_start = base;
1158 phyp_dump_info->init_reserve_size = size;
1162 static inline void __init phyp_dump_reserve_mem(void) {}
1163 #endif /* CONFIG_PHYP_DUMP && CONFIG_PPC_RTAS */
1166 void __init early_init_devtree(void *params)
1168 unsigned long limit;
1170 DBG(" -> early_init_devtree(%p)\n", params);
1172 /* Setup flat device-tree pointer */
1173 initial_boot_params = params;
1175 #ifdef CONFIG_PPC_RTAS
1176 /* Some machines might need RTAS info for debugging, grab it now. */
1177 of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
1180 #ifdef CONFIG_PHYP_DUMP
1181 /* scan tree to see if dump occured during last boot */
1182 of_scan_flat_dt(early_init_dt_scan_phyp_dump, NULL);
1185 /* Retrieve various informations from the /chosen node of the
1186 * device-tree, including the platform type, initrd location and
1187 * size, TCE reserve, and more ...
1189 of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
1191 /* Scan memory nodes and rebuild LMBs */
1193 of_scan_flat_dt(early_init_dt_scan_root, NULL);
1194 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1196 /* Save command line for /proc/cmdline and then parse parameters */
1197 strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE);
1198 parse_early_param();
1200 /* Reserve LMB regions used by kernel, initrd, dt, etc... */
1201 lmb_reserve(PHYSICAL_START, __pa(klimit) - PHYSICAL_START);
1202 /* If relocatable, reserve first 32k for interrupt vectors etc. */
1203 if (PHYSICAL_START > MEMORY_START)
1204 lmb_reserve(MEMORY_START, 0x8000);
1205 reserve_kdump_trampoline();
1206 reserve_crashkernel();
1207 early_reserve_mem();
1208 phyp_dump_reserve_mem();
1210 limit = memory_limit;
1212 unsigned long memsize;
1214 /* Ensure that total memory size is page-aligned, because
1215 * otherwise mark_bootmem() gets upset. */
1217 memsize = lmb_phys_mem_size();
1218 if ((memsize & PAGE_MASK) != memsize)
1219 limit = memsize & PAGE_MASK;
1221 lmb_enforce_memory_limit(limit);
1225 DBG("Phys. mem: %lx\n", lmb_phys_mem_size());
1227 /* We may need to relocate the flat tree, do it now.
1228 * FIXME .. and the initrd too? */
1231 DBG("Scanning CPUs ...\n");
1233 /* Retreive CPU related informations from the flat tree
1234 * (altivec support, boot CPU ID, ...)
1236 of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
1238 DBG(" <- early_init_devtree()\n");
1243 * Indicates whether the root node has a given value in its
1244 * compatible property.
1246 int machine_is_compatible(const char *compat)
1248 struct device_node *root;
1251 root = of_find_node_by_path("/");
1253 rc = of_device_is_compatible(root, compat);
1258 EXPORT_SYMBOL(machine_is_compatible);
1262 * New implementation of the OF "find" APIs, return a refcounted
1263 * object, call of_node_put() when done. The device tree and list
1264 * are protected by a rw_lock.
1266 * Note that property management will need some locking as well,
1267 * this isn't dealt with yet.
1272 * of_find_node_by_phandle - Find a node given a phandle
1273 * @handle: phandle of the node to find
1275 * Returns a node pointer with refcount incremented, use
1276 * of_node_put() on it when done.
1278 struct device_node *of_find_node_by_phandle(phandle handle)
1280 struct device_node *np;
1282 read_lock(&devtree_lock);
1283 for (np = allnodes; np != 0; np = np->allnext)
1284 if (np->linux_phandle == handle)
1287 read_unlock(&devtree_lock);
1290 EXPORT_SYMBOL(of_find_node_by_phandle);
1293 * of_find_next_cache_node - Find a node's subsidiary cache
1294 * @np: node of type "cpu" or "cache"
1296 * Returns a node pointer with refcount incremented, use
1297 * of_node_put() on it when done. Caller should hold a reference
1300 struct device_node *of_find_next_cache_node(struct device_node *np)
1302 struct device_node *child;
1303 const phandle *handle;
1305 handle = of_get_property(np, "l2-cache", NULL);
1307 handle = of_get_property(np, "next-level-cache", NULL);
1310 return of_find_node_by_phandle(*handle);
1312 /* OF on pmac has nodes instead of properties named "l2-cache"
1313 * beneath CPU nodes.
1315 if (!strcmp(np->type, "cpu"))
1316 for_each_child_of_node(np, child)
1317 if (!strcmp(child->type, "cache"))
1324 * of_find_all_nodes - Get next node in global list
1325 * @prev: Previous node or NULL to start iteration
1326 * of_node_put() will be called on it
1328 * Returns a node pointer with refcount incremented, use
1329 * of_node_put() on it when done.
1331 struct device_node *of_find_all_nodes(struct device_node *prev)
1333 struct device_node *np;
1335 read_lock(&devtree_lock);
1336 np = prev ? prev->allnext : allnodes;
1337 for (; np != 0; np = np->allnext)
1338 if (of_node_get(np))
1341 read_unlock(&devtree_lock);
1344 EXPORT_SYMBOL(of_find_all_nodes);
1347 * of_node_get - Increment refcount of a node
1348 * @node: Node to inc refcount, NULL is supported to
1349 * simplify writing of callers
1353 struct device_node *of_node_get(struct device_node *node)
1356 kref_get(&node->kref);
1359 EXPORT_SYMBOL(of_node_get);
1361 static inline struct device_node * kref_to_device_node(struct kref *kref)
1363 return container_of(kref, struct device_node, kref);
1367 * of_node_release - release a dynamically allocated node
1368 * @kref: kref element of the node to be released
1370 * In of_node_put() this function is passed to kref_put()
1371 * as the destructor.
1373 static void of_node_release(struct kref *kref)
1375 struct device_node *node = kref_to_device_node(kref);
1376 struct property *prop = node->properties;
1378 /* We should never be releasing nodes that haven't been detached. */
1379 if (!of_node_check_flag(node, OF_DETACHED)) {
1380 printk("WARNING: Bad of_node_put() on %s\n", node->full_name);
1382 kref_init(&node->kref);
1386 if (!of_node_check_flag(node, OF_DYNAMIC))
1390 struct property *next = prop->next;
1397 prop = node->deadprops;
1398 node->deadprops = NULL;
1401 kfree(node->full_name);
1407 * of_node_put - Decrement refcount of a node
1408 * @node: Node to dec refcount, NULL is supported to
1409 * simplify writing of callers
1412 void of_node_put(struct device_node *node)
1415 kref_put(&node->kref, of_node_release);
1417 EXPORT_SYMBOL(of_node_put);
1420 * Plug a device node into the tree and global list.
1422 void of_attach_node(struct device_node *np)
1424 unsigned long flags;
1426 write_lock_irqsave(&devtree_lock, flags);
1427 np->sibling = np->parent->child;
1428 np->allnext = allnodes;
1429 np->parent->child = np;
1431 write_unlock_irqrestore(&devtree_lock, flags);
1435 * "Unplug" a node from the device tree. The caller must hold
1436 * a reference to the node. The memory associated with the node
1437 * is not freed until its refcount goes to zero.
1439 void of_detach_node(struct device_node *np)
1441 struct device_node *parent;
1442 unsigned long flags;
1444 write_lock_irqsave(&devtree_lock, flags);
1446 parent = np->parent;
1451 allnodes = np->allnext;
1453 struct device_node *prev;
1454 for (prev = allnodes;
1455 prev->allnext != np;
1456 prev = prev->allnext)
1458 prev->allnext = np->allnext;
1461 if (parent->child == np)
1462 parent->child = np->sibling;
1464 struct device_node *prevsib;
1465 for (prevsib = np->parent->child;
1466 prevsib->sibling != np;
1467 prevsib = prevsib->sibling)
1469 prevsib->sibling = np->sibling;
1472 of_node_set_flag(np, OF_DETACHED);
1475 write_unlock_irqrestore(&devtree_lock, flags);
1478 #ifdef CONFIG_PPC_PSERIES
1480 * Fix up the uninitialized fields in a new device node:
1481 * name, type and pci-specific fields
1484 static int of_finish_dynamic_node(struct device_node *node)
1486 struct device_node *parent = of_get_parent(node);
1488 const phandle *ibm_phandle;
1490 node->name = of_get_property(node, "name", NULL);
1491 node->type = of_get_property(node, "device_type", NULL);
1494 node->name = "<NULL>";
1496 node->type = "<NULL>";
1503 /* We don't support that function on PowerMac, at least
1506 if (machine_is(powermac))
1509 /* fix up new node's linux_phandle field */
1510 if ((ibm_phandle = of_get_property(node, "ibm,phandle", NULL)))
1511 node->linux_phandle = *ibm_phandle;
1514 of_node_put(parent);
1518 static int prom_reconfig_notifier(struct notifier_block *nb,
1519 unsigned long action, void *node)
1524 case PSERIES_RECONFIG_ADD:
1525 err = of_finish_dynamic_node(node);
1527 printk(KERN_ERR "finish_node returned %d\n", err);
1538 static struct notifier_block prom_reconfig_nb = {
1539 .notifier_call = prom_reconfig_notifier,
1540 .priority = 10, /* This one needs to run first */
1543 static int __init prom_reconfig_setup(void)
1545 return pSeries_reconfig_notifier_register(&prom_reconfig_nb);
1547 __initcall(prom_reconfig_setup);
1551 * Add a property to a node
1553 int prom_add_property(struct device_node* np, struct property* prop)
1555 struct property **next;
1556 unsigned long flags;
1559 write_lock_irqsave(&devtree_lock, flags);
1560 next = &np->properties;
1562 if (strcmp(prop->name, (*next)->name) == 0) {
1563 /* duplicate ! don't insert it */
1564 write_unlock_irqrestore(&devtree_lock, flags);
1567 next = &(*next)->next;
1570 write_unlock_irqrestore(&devtree_lock, flags);
1572 #ifdef CONFIG_PROC_DEVICETREE
1573 /* try to add to proc as well if it was initialized */
1575 proc_device_tree_add_prop(np->pde, prop);
1576 #endif /* CONFIG_PROC_DEVICETREE */
1582 * Remove a property from a node. Note that we don't actually
1583 * remove it, since we have given out who-knows-how-many pointers
1584 * to the data using get-property. Instead we just move the property
1585 * to the "dead properties" list, so it won't be found any more.
1587 int prom_remove_property(struct device_node *np, struct property *prop)
1589 struct property **next;
1590 unsigned long flags;
1593 write_lock_irqsave(&devtree_lock, flags);
1594 next = &np->properties;
1596 if (*next == prop) {
1597 /* found the node */
1599 prop->next = np->deadprops;
1600 np->deadprops = prop;
1604 next = &(*next)->next;
1606 write_unlock_irqrestore(&devtree_lock, flags);
1611 #ifdef CONFIG_PROC_DEVICETREE
1612 /* try to remove the proc node as well */
1614 proc_device_tree_remove_prop(np->pde, prop);
1615 #endif /* CONFIG_PROC_DEVICETREE */
1621 * Update a property in a node. Note that we don't actually
1622 * remove it, since we have given out who-knows-how-many pointers
1623 * to the data using get-property. Instead we just move the property
1624 * to the "dead properties" list, and add the new property to the
1627 int prom_update_property(struct device_node *np,
1628 struct property *newprop,
1629 struct property *oldprop)
1631 struct property **next;
1632 unsigned long flags;
1635 write_lock_irqsave(&devtree_lock, flags);
1636 next = &np->properties;
1638 if (*next == oldprop) {
1639 /* found the node */
1640 newprop->next = oldprop->next;
1642 oldprop->next = np->deadprops;
1643 np->deadprops = oldprop;
1647 next = &(*next)->next;
1649 write_unlock_irqrestore(&devtree_lock, flags);
1654 #ifdef CONFIG_PROC_DEVICETREE
1655 /* try to add to proc as well if it was initialized */
1657 proc_device_tree_update_prop(np->pde, newprop, oldprop);
1658 #endif /* CONFIG_PROC_DEVICETREE */
1664 /* Find the device node for a given logical cpu number, also returns the cpu
1665 * local thread number (index in ibm,interrupt-server#s) if relevant and
1666 * asked for (non NULL)
1668 struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
1671 struct device_node *np;
1673 hardid = get_hard_smp_processor_id(cpu);
1675 for_each_node_by_type(np, "cpu") {
1677 unsigned int plen, t;
1679 /* Check for ibm,ppc-interrupt-server#s. If it doesn't exist
1680 * fallback to "reg" property and assume no threads
1682 intserv = of_get_property(np, "ibm,ppc-interrupt-server#s",
1684 if (intserv == NULL) {
1685 const u32 *reg = of_get_property(np, "reg", NULL);
1688 if (*reg == hardid) {
1694 plen /= sizeof(u32);
1695 for (t = 0; t < plen; t++) {
1696 if (hardid == intserv[t]) {
1706 EXPORT_SYMBOL(of_get_cpu_node);
1708 #if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
1709 static struct debugfs_blob_wrapper flat_dt_blob;
1711 static int __init export_flat_device_tree(void)
1715 flat_dt_blob.data = initial_boot_params;
1716 flat_dt_blob.size = initial_boot_params->totalsize;
1718 d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR,
1719 powerpc_debugfs_root, &flat_dt_blob);
1725 __initcall(export_flat_device_tree);