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/config.h>
20 #include <linux/kernel.h>
21 #include <linux/string.h>
22 #include <linux/init.h>
23 #include <linux/threads.h>
24 #include <linux/spinlock.h>
25 #include <linux/types.h>
26 #include <linux/pci.h>
27 #include <linux/stringify.h>
28 #include <linux/delay.h>
29 #include <linux/initrd.h>
30 #include <linux/bitops.h>
31 #include <linux/module.h>
32 #include <linux/kexec.h>
38 #include <asm/processor.h>
41 #include <asm/kdump.h>
43 #include <asm/system.h>
45 #include <asm/pgtable.h>
47 #include <asm/iommu.h>
48 #include <asm/btext.h>
49 #include <asm/sections.h>
50 #include <asm/machdep.h>
51 #include <asm/pSeries_reconfig.h>
52 #include <asm/pci-bridge.h>
55 #define DBG(fmt...) printk(KERN_ERR fmt)
61 static int __initdata dt_root_addr_cells;
62 static int __initdata dt_root_size_cells;
65 static int __initdata iommu_is_off;
66 int __initdata iommu_force_on;
67 unsigned long tce_alloc_start, tce_alloc_end;
73 static struct boot_param_header *initial_boot_params __initdata;
75 struct boot_param_header *initial_boot_params;
78 static struct device_node *allnodes = NULL;
80 /* use when traversing tree through the allnext, child, sibling,
81 * or parent members of struct device_node.
83 static DEFINE_RWLOCK(devtree_lock);
85 /* export that to outside world */
86 struct device_node *of_chosen;
88 struct device_node *dflt_interrupt_controller;
89 int num_interrupt_controllers;
92 * Wrapper for allocating memory for various data that needs to be
93 * attached to device nodes as they are processed at boot or when
94 * added to the device tree later (e.g. DLPAR). At boot there is
95 * already a region reserved so we just increment *mem_start by size;
96 * otherwise we call kmalloc.
98 static void * prom_alloc(unsigned long size, unsigned long *mem_start)
103 return kmalloc(size, GFP_KERNEL);
111 * Find the device_node with a given phandle.
113 static struct device_node * find_phandle(phandle ph)
115 struct device_node *np;
117 for (np = allnodes; np != 0; np = np->allnext)
118 if (np->linux_phandle == ph)
124 * Find the interrupt parent of a node.
126 static struct device_node * __devinit intr_parent(struct device_node *p)
130 parp = (phandle *) get_property(p, "interrupt-parent", NULL);
133 p = find_phandle(*parp);
137 * On a powermac booted with BootX, we don't get to know the
138 * phandles for any nodes, so find_phandle will return NULL.
139 * Fortunately these machines only have one interrupt controller
140 * so there isn't in fact any ambiguity. -- paulus
142 if (num_interrupt_controllers == 1)
143 p = dflt_interrupt_controller;
148 * Find out the size of each entry of the interrupts property
151 int __devinit prom_n_intr_cells(struct device_node *np)
153 struct device_node *p;
156 for (p = np; (p = intr_parent(p)) != NULL; ) {
157 icp = (unsigned int *)
158 get_property(p, "#interrupt-cells", NULL);
161 if (get_property(p, "interrupt-controller", NULL) != NULL
162 || get_property(p, "interrupt-map", NULL) != NULL) {
163 printk("oops, node %s doesn't have #interrupt-cells\n",
169 printk("prom_n_intr_cells failed for %s\n", np->full_name);
175 * Map an interrupt from a device up to the platform interrupt
178 static int __devinit map_interrupt(unsigned int **irq, struct device_node **ictrler,
179 struct device_node *np, unsigned int *ints,
182 struct device_node *p, *ipar;
183 unsigned int *imap, *imask, *ip;
184 int i, imaplen, match;
185 int newintrc = 0, newaddrc = 0;
189 reg = (unsigned int *) get_property(np, "reg", NULL);
190 naddrc = prom_n_addr_cells(np);
193 if (get_property(p, "interrupt-controller", NULL) != NULL)
194 /* this node is an interrupt controller, stop here */
196 imap = (unsigned int *)
197 get_property(p, "interrupt-map", &imaplen);
202 imask = (unsigned int *)
203 get_property(p, "interrupt-map-mask", NULL);
205 printk("oops, %s has interrupt-map but no mask\n",
209 imaplen /= sizeof(unsigned int);
212 while (imaplen > 0 && !match) {
213 /* check the child-interrupt field */
215 for (i = 0; i < naddrc && match; ++i)
216 match = ((reg[i] ^ imap[i]) & imask[i]) == 0;
217 for (; i < naddrc + nintrc && match; ++i)
218 match = ((ints[i-naddrc] ^ imap[i]) & imask[i]) == 0;
219 imap += naddrc + nintrc;
220 imaplen -= naddrc + nintrc;
221 /* grab the interrupt parent */
222 ipar = find_phandle((phandle) *imap++);
224 if (ipar == NULL && num_interrupt_controllers == 1)
225 /* cope with BootX not giving us phandles */
226 ipar = dflt_interrupt_controller;
228 printk("oops, no int parent %x in map of %s\n",
229 imap[-1], p->full_name);
232 /* find the parent's # addr and intr cells */
233 ip = (unsigned int *)
234 get_property(ipar, "#interrupt-cells", NULL);
236 printk("oops, no #interrupt-cells on %s\n",
241 ip = (unsigned int *)
242 get_property(ipar, "#address-cells", NULL);
243 newaddrc = (ip == NULL)? 0: *ip;
244 imap += newaddrc + newintrc;
245 imaplen -= newaddrc + newintrc;
248 printk("oops, error decoding int-map on %s, len=%d\n",
249 p->full_name, imaplen);
254 printk("oops, no match in %s int-map for %s\n",
255 p->full_name, np->full_name);
262 ints = imap - nintrc;
267 printk("hmmm, int tree for %s doesn't have ctrler\n",
277 static unsigned char map_isa_senses[4] = {
278 IRQ_SENSE_LEVEL | IRQ_POLARITY_NEGATIVE,
279 IRQ_SENSE_LEVEL | IRQ_POLARITY_POSITIVE,
280 IRQ_SENSE_EDGE | IRQ_POLARITY_NEGATIVE,
281 IRQ_SENSE_EDGE | IRQ_POLARITY_POSITIVE
284 static unsigned char map_mpic_senses[4] = {
285 IRQ_SENSE_EDGE | IRQ_POLARITY_POSITIVE,
286 IRQ_SENSE_LEVEL | IRQ_POLARITY_NEGATIVE,
287 /* 2 seems to be used for the 8259 cascade... */
288 IRQ_SENSE_LEVEL | IRQ_POLARITY_POSITIVE,
289 IRQ_SENSE_EDGE | IRQ_POLARITY_NEGATIVE,
292 static int __devinit finish_node_interrupts(struct device_node *np,
293 unsigned long *mem_start,
297 int intlen, intrcells, intrcount;
299 unsigned int *irq, virq;
300 struct device_node *ic;
302 if (num_interrupt_controllers == 0) {
304 * Old machines just have a list of interrupt numbers
305 * and no interrupt-controller nodes.
307 ints = (unsigned int *) get_property(np, "AAPL,interrupts",
309 /* XXX old interpret_pci_props looked in parent too */
310 /* XXX old interpret_macio_props looked for interrupts
311 before AAPL,interrupts */
313 ints = (unsigned int *) get_property(np, "interrupts",
318 np->n_intrs = intlen / sizeof(unsigned int);
319 np->intrs = prom_alloc(np->n_intrs * sizeof(np->intrs[0]),
326 for (i = 0; i < np->n_intrs; ++i) {
327 np->intrs[i].line = *ints++;
328 np->intrs[i].sense = IRQ_SENSE_LEVEL
329 | IRQ_POLARITY_NEGATIVE;
334 ints = (unsigned int *) get_property(np, "interrupts", &intlen);
337 intrcells = prom_n_intr_cells(np);
338 intlen /= intrcells * sizeof(unsigned int);
340 np->intrs = prom_alloc(intlen * sizeof(*(np->intrs)), mem_start);
348 for (i = 0; i < intlen; ++i, ints += intrcells) {
349 n = map_interrupt(&irq, &ic, np, ints, intrcells);
353 /* don't map IRQ numbers under a cascaded 8259 controller */
354 if (ic && device_is_compatible(ic, "chrp,iic")) {
355 np->intrs[intrcount].line = irq[0];
356 sense = (n > 1)? (irq[1] & 3): 3;
357 np->intrs[intrcount].sense = map_isa_senses[sense];
359 virq = virt_irq_create_mapping(irq[0]);
361 if (virq == NO_IRQ) {
362 printk(KERN_CRIT "Could not allocate interrupt"
363 " number for %s\n", np->full_name);
367 np->intrs[intrcount].line = irq_offset_up(virq);
368 sense = (n > 1)? (irq[1] & 3): 1;
369 np->intrs[intrcount].sense = map_mpic_senses[sense];
373 /* We offset irq numbers for the u3 MPIC by 128 in PowerMac */
374 if (_machine == PLATFORM_POWERMAC && ic && ic->parent) {
375 char *name = get_property(ic->parent, "name", NULL);
376 if (name && !strcmp(name, "u3"))
377 np->intrs[intrcount].line += 128;
378 else if (!(name && !strcmp(name, "mac-io")))
379 /* ignore other cascaded controllers, such as
385 printk("hmmm, got %d intr cells for %s:", n,
387 for (j = 0; j < n; ++j)
388 printk(" %d", irq[j]);
393 np->n_intrs = intrcount;
398 static int __devinit finish_node(struct device_node *np,
399 unsigned long *mem_start,
402 struct device_node *child;
405 rc = finish_node_interrupts(np, mem_start, measure_only);
409 for (child = np->child; child != NULL; child = child->sibling) {
410 rc = finish_node(child, mem_start, measure_only);
418 static void __init scan_interrupt_controllers(void)
420 struct device_node *np;
425 for (np = allnodes; np != NULL; np = np->allnext) {
426 ic = get_property(np, "interrupt-controller", &iclen);
427 name = get_property(np, "name", NULL);
428 /* checking iclen makes sure we don't get a false
429 match on /chosen.interrupt_controller */
431 && strcmp(name, "interrupt-controller") == 0)
432 || (ic != NULL && iclen == 0
433 && strcmp(name, "AppleKiwi"))) {
435 dflt_interrupt_controller = np;
439 num_interrupt_controllers = n;
443 * finish_device_tree is called once things are running normally
444 * (i.e. with text and data mapped to the address they were linked at).
445 * It traverses the device tree and fills in some of the additional,
446 * fields in each node like {n_}addrs and {n_}intrs, the virt interrupt
447 * mapping is also initialized at this point.
449 void __init finish_device_tree(void)
451 unsigned long start, end, size = 0;
453 DBG(" -> finish_device_tree\n");
456 /* Initialize virtual IRQ map */
459 scan_interrupt_controllers();
462 * Finish device-tree (pre-parsing some properties etc...)
463 * We do this in 2 passes. One with "measure_only" set, which
464 * will only measure the amount of memory needed, then we can
465 * allocate that memory, and call finish_node again. However,
466 * we must be careful as most routines will fail nowadays when
467 * prom_alloc() returns 0, so we must make sure our first pass
468 * doesn't start at 0. We pre-initialize size to 16 for that
469 * reason and then remove those additional 16 bytes
472 finish_node(allnodes, &size, 1);
474 end = start = (unsigned long) __va(lmb_alloc(size, 128));
475 finish_node(allnodes, &end, 0);
476 BUG_ON(end != start + size);
478 DBG(" <- finish_device_tree\n");
481 static inline char *find_flat_dt_string(u32 offset)
483 return ((char *)initial_boot_params) +
484 initial_boot_params->off_dt_strings + offset;
488 * This function is used to scan the flattened device-tree, it is
489 * used to extract the memory informations at boot before we can
492 int __init of_scan_flat_dt(int (*it)(unsigned long node,
493 const char *uname, int depth,
497 unsigned long p = ((unsigned long)initial_boot_params) +
498 initial_boot_params->off_dt_struct;
503 u32 tag = *((u32 *)p);
507 if (tag == OF_DT_END_NODE) {
511 if (tag == OF_DT_NOP)
513 if (tag == OF_DT_END)
515 if (tag == OF_DT_PROP) {
516 u32 sz = *((u32 *)p);
518 if (initial_boot_params->version < 0x10)
519 p = _ALIGN(p, sz >= 8 ? 8 : 4);
524 if (tag != OF_DT_BEGIN_NODE) {
525 printk(KERN_WARNING "Invalid tag %x scanning flattened"
526 " device tree !\n", tag);
531 p = _ALIGN(p + strlen(pathp) + 1, 4);
532 if ((*pathp) == '/') {
534 for (lp = NULL, np = pathp; *np; np++)
540 rc = it(p, pathp, depth, data);
549 * This function can be used within scan_flattened_dt callback to get
550 * access to properties
552 void* __init of_get_flat_dt_prop(unsigned long node, const char *name,
555 unsigned long p = node;
558 u32 tag = *((u32 *)p);
563 if (tag == OF_DT_NOP)
565 if (tag != OF_DT_PROP)
569 noff = *((u32 *)(p + 4));
571 if (initial_boot_params->version < 0x10)
572 p = _ALIGN(p, sz >= 8 ? 8 : 4);
574 nstr = find_flat_dt_string(noff);
576 printk(KERN_WARNING "Can't find property index"
580 if (strcmp(name, nstr) == 0) {
590 static void *__init unflatten_dt_alloc(unsigned long *mem, unsigned long size,
595 *mem = _ALIGN(*mem, align);
602 static unsigned long __init unflatten_dt_node(unsigned long mem,
604 struct device_node *dad,
605 struct device_node ***allnextpp,
606 unsigned long fpsize)
608 struct device_node *np;
609 struct property *pp, **prev_pp = NULL;
612 unsigned int l, allocl;
616 tag = *((u32 *)(*p));
617 if (tag != OF_DT_BEGIN_NODE) {
618 printk("Weird tag at start of node: %x\n", tag);
623 l = allocl = strlen(pathp) + 1;
624 *p = _ALIGN(*p + l, 4);
626 /* version 0x10 has a more compact unit name here instead of the full
627 * path. we accumulate the full path size using "fpsize", we'll rebuild
628 * it later. We detect this because the first character of the name is
631 if ((*pathp) != '/') {
634 /* root node: special case. fpsize accounts for path
635 * plus terminating zero. root node only has '/', so
636 * fpsize should be 2, but we want to avoid the first
637 * level nodes to have two '/' so we use fpsize 1 here
642 /* account for '/' and path size minus terminal 0
651 np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
652 __alignof__(struct device_node));
654 memset(np, 0, sizeof(*np));
655 np->full_name = ((char*)np) + sizeof(struct device_node);
657 char *p = np->full_name;
658 /* rebuild full path for new format */
659 if (dad && dad->parent) {
660 strcpy(p, dad->full_name);
662 if ((strlen(p) + l + 1) != allocl) {
663 DBG("%s: p: %d, l: %d, a: %d\n",
664 pathp, strlen(p), l, allocl);
672 memcpy(np->full_name, pathp, l);
673 prev_pp = &np->properties;
675 *allnextpp = &np->allnext;
678 /* we temporarily use the next field as `last_child'*/
682 dad->next->sibling = np;
685 kref_init(&np->kref);
691 tag = *((u32 *)(*p));
692 if (tag == OF_DT_NOP) {
696 if (tag != OF_DT_PROP)
700 noff = *((u32 *)((*p) + 4));
702 if (initial_boot_params->version < 0x10)
703 *p = _ALIGN(*p, sz >= 8 ? 8 : 4);
705 pname = find_flat_dt_string(noff);
707 printk("Can't find property name in list !\n");
710 if (strcmp(pname, "name") == 0)
712 l = strlen(pname) + 1;
713 pp = unflatten_dt_alloc(&mem, sizeof(struct property),
714 __alignof__(struct property));
716 if (strcmp(pname, "linux,phandle") == 0) {
717 np->node = *((u32 *)*p);
718 if (np->linux_phandle == 0)
719 np->linux_phandle = np->node;
721 if (strcmp(pname, "ibm,phandle") == 0)
722 np->linux_phandle = *((u32 *)*p);
725 pp->value = (void *)*p;
729 *p = _ALIGN((*p) + sz, 4);
731 /* with version 0x10 we may not have the name property, recreate
732 * it here from the unit name if absent
735 char *p = pathp, *ps = pathp, *pa = NULL;
748 pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
749 __alignof__(struct property));
753 pp->value = (unsigned char *)(pp + 1);
756 memcpy(pp->value, ps, sz - 1);
757 ((char *)pp->value)[sz - 1] = 0;
758 DBG("fixed up name for %s -> %s\n", pathp, pp->value);
763 np->name = get_property(np, "name", NULL);
764 np->type = get_property(np, "device_type", NULL);
771 while (tag == OF_DT_BEGIN_NODE) {
772 mem = unflatten_dt_node(mem, p, np, allnextpp, fpsize);
773 tag = *((u32 *)(*p));
775 if (tag != OF_DT_END_NODE) {
776 printk("Weird tag at end of node: %x\n", tag);
785 * unflattens the device-tree passed by the firmware, creating the
786 * tree of struct device_node. It also fills the "name" and "type"
787 * pointers of the nodes so the normal device-tree walking functions
788 * can be used (this used to be done by finish_device_tree)
790 void __init unflatten_device_tree(void)
792 unsigned long start, mem, size;
793 struct device_node **allnextp = &allnodes;
797 DBG(" -> unflatten_device_tree()\n");
799 /* First pass, scan for size */
800 start = ((unsigned long)initial_boot_params) +
801 initial_boot_params->off_dt_struct;
802 size = unflatten_dt_node(0, &start, NULL, NULL, 0);
803 size = (size | 3) + 1;
805 DBG(" size is %lx, allocating...\n", size);
807 /* Allocate memory for the expanded device tree */
808 mem = lmb_alloc(size + 4, __alignof__(struct device_node));
810 DBG("Couldn't allocate memory with lmb_alloc()!\n");
811 panic("Couldn't allocate memory with lmb_alloc()!\n");
813 mem = (unsigned long) __va(mem);
815 ((u32 *)mem)[size / 4] = 0xdeadbeef;
817 DBG(" unflattening %lx...\n", mem);
819 /* Second pass, do actual unflattening */
820 start = ((unsigned long)initial_boot_params) +
821 initial_boot_params->off_dt_struct;
822 unflatten_dt_node(mem, &start, NULL, &allnextp, 0);
823 if (*((u32 *)start) != OF_DT_END)
824 printk(KERN_WARNING "Weird tag at end of tree: %08x\n", *((u32 *)start));
825 if (((u32 *)mem)[size / 4] != 0xdeadbeef)
826 printk(KERN_WARNING "End of tree marker overwritten: %08x\n",
827 ((u32 *)mem)[size / 4] );
830 /* Get pointer to OF "/chosen" node for use everywhere */
831 of_chosen = of_find_node_by_path("/chosen");
832 if (of_chosen == NULL)
833 of_chosen = of_find_node_by_path("/chosen@0");
835 /* Retreive command line */
836 if (of_chosen != NULL) {
837 p = (char *)get_property(of_chosen, "bootargs", &l);
838 if (p != NULL && l > 0)
839 strlcpy(cmd_line, p, min(l, COMMAND_LINE_SIZE));
841 #ifdef CONFIG_CMDLINE
842 if (l == 0 || (l == 1 && (*p) == 0))
843 strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
844 #endif /* CONFIG_CMDLINE */
846 DBG("Command line is: %s\n", cmd_line);
848 DBG(" <- unflatten_device_tree()\n");
852 static int __init early_init_dt_scan_cpus(unsigned long node,
853 const char *uname, int depth, void *data)
857 char *type = of_get_flat_dt_prop(node, "device_type", &size);
859 /* We are scanning "cpu" nodes only */
860 if (type == NULL || strcmp(type, "cpu") != 0)
865 if (initial_boot_params && initial_boot_params->version >= 2) {
866 /* version 2 of the kexec param format adds the phys cpuid
869 boot_cpuid_phys = initial_boot_params->boot_cpuid_phys;
871 /* Check if it's the boot-cpu, set it's hw index now */
872 if (of_get_flat_dt_prop(node,
873 "linux,boot-cpu", NULL) != NULL) {
874 prop = of_get_flat_dt_prop(node, "reg", NULL);
876 boot_cpuid_phys = *prop;
879 set_hard_smp_processor_id(0, boot_cpuid_phys);
881 #ifdef CONFIG_ALTIVEC
882 /* Check if we have a VMX and eventually update CPU features */
883 prop = (u32 *)of_get_flat_dt_prop(node, "ibm,vmx", NULL);
884 if (prop && (*prop) > 0) {
885 cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
886 cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
889 /* Same goes for Apple's "altivec" property */
890 prop = (u32 *)of_get_flat_dt_prop(node, "altivec", NULL);
892 cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
893 cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
895 #endif /* CONFIG_ALTIVEC */
897 #ifdef CONFIG_PPC_PSERIES
899 * Check for an SMT capable CPU and set the CPU feature. We do
900 * this by looking at the size of the ibm,ppc-interrupt-server#s
903 prop = (u32 *)of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s",
905 cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
906 if (prop && ((size / sizeof(u32)) > 1))
907 cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
913 static int __init early_init_dt_scan_chosen(unsigned long node,
914 const char *uname, int depth, void *data)
917 unsigned long *lprop;
919 DBG("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
922 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
925 /* get platform type */
926 prop = (u32 *)of_get_flat_dt_prop(node, "linux,platform", NULL);
929 #ifdef CONFIG_PPC_MULTIPLATFORM
934 /* check if iommu is forced on or off */
935 if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
937 if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
941 lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
943 memory_limit = *lprop;
946 lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
948 tce_alloc_start = *lprop;
949 lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
951 tce_alloc_end = *lprop;
954 #ifdef CONFIG_PPC_RTAS
955 /* To help early debugging via the front panel, we retreive a minimal
956 * set of RTAS infos now if available
961 basep = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
962 entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
963 prop = of_get_flat_dt_prop(node, "linux,rtas-size", NULL);
964 if (basep && entryp && prop) {
966 rtas.entry = *entryp;
970 #endif /* CONFIG_PPC_RTAS */
973 lprop = (u64*)of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
975 crashk_res.start = *lprop;
977 lprop = (u64*)of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
979 crashk_res.end = crashk_res.start + *lprop - 1;
986 static int __init early_init_dt_scan_root(unsigned long node,
987 const char *uname, int depth, void *data)
994 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
995 dt_root_size_cells = (prop == NULL) ? 1 : *prop;
996 DBG("dt_root_size_cells = %x\n", dt_root_size_cells);
998 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
999 dt_root_addr_cells = (prop == NULL) ? 2 : *prop;
1000 DBG("dt_root_addr_cells = %x\n", dt_root_addr_cells);
1006 static unsigned long __init dt_mem_next_cell(int s, cell_t **cellp)
1011 /* Ignore more than 2 cells */
1012 while (s > sizeof(unsigned long) / 4) {
1030 static int __init early_init_dt_scan_memory(unsigned long node,
1031 const char *uname, int depth, void *data)
1033 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
1037 /* We are scanning "memory" nodes only */
1040 * The longtrail doesn't have a device_type on the
1041 * /memory node, so look for the node called /memory@0.
1043 if (depth != 1 || strcmp(uname, "memory@0") != 0)
1045 } else if (strcmp(type, "memory") != 0)
1048 reg = (cell_t *)of_get_flat_dt_prop(node, "linux,usable-memory", &l);
1050 reg = (cell_t *)of_get_flat_dt_prop(node, "reg", &l);
1054 endp = reg + (l / sizeof(cell_t));
1056 DBG("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
1057 uname, l, reg[0], reg[1], reg[2], reg[3]);
1059 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
1060 unsigned long base, size;
1062 base = dt_mem_next_cell(dt_root_addr_cells, ®);
1063 size = dt_mem_next_cell(dt_root_size_cells, ®);
1067 DBG(" - %lx , %lx\n", base, size);
1070 if (base >= 0x80000000ul)
1072 if ((base + size) > 0x80000000ul)
1073 size = 0x80000000ul - base;
1076 lmb_add(base, size);
1081 static void __init early_reserve_mem(void)
1083 unsigned long base, size;
1084 unsigned long *reserve_map;
1086 reserve_map = (unsigned long *)(((unsigned long)initial_boot_params) +
1087 initial_boot_params->off_mem_rsvmap);
1089 base = *(reserve_map++);
1090 size = *(reserve_map++);
1093 DBG("reserving: %lx -> %lx\n", base, size);
1094 lmb_reserve(base, size);
1098 DBG("memory reserved, lmbs :\n");
1103 void __init early_init_devtree(void *params)
1105 DBG(" -> early_init_devtree()\n");
1107 /* Setup flat device-tree pointer */
1108 initial_boot_params = params;
1110 /* Retrieve various informations from the /chosen node of the
1111 * device-tree, including the platform type, initrd location and
1112 * size, TCE reserve, and more ...
1114 of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
1116 /* Scan memory nodes and rebuild LMBs */
1118 of_scan_flat_dt(early_init_dt_scan_root, NULL);
1119 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1120 lmb_enforce_memory_limit(memory_limit);
1123 DBG("Phys. mem: %lx\n", lmb_phys_mem_size());
1125 /* Reserve LMB regions used by kernel, initrd, dt, etc... */
1126 lmb_reserve(PHYSICAL_START, __pa(klimit) - PHYSICAL_START);
1127 #ifdef CONFIG_CRASH_DUMP
1128 lmb_reserve(0, KDUMP_RESERVE_LIMIT);
1130 early_reserve_mem();
1132 DBG("Scanning CPUs ...\n");
1134 /* Retreive CPU related informations from the flat tree
1135 * (altivec support, boot CPU ID, ...)
1137 of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
1139 DBG(" <- early_init_devtree()\n");
1145 prom_n_addr_cells(struct device_node* np)
1151 ip = (int *) get_property(np, "#address-cells", NULL);
1154 } while (np->parent);
1155 /* No #address-cells property for the root node, default to 1 */
1158 EXPORT_SYMBOL(prom_n_addr_cells);
1161 prom_n_size_cells(struct device_node* np)
1167 ip = (int *) get_property(np, "#size-cells", NULL);
1170 } while (np->parent);
1171 /* No #size-cells property for the root node, default to 1 */
1174 EXPORT_SYMBOL(prom_n_size_cells);
1177 * Work out the sense (active-low level / active-high edge)
1178 * of each interrupt from the device tree.
1180 void __init prom_get_irq_senses(unsigned char *senses, int off, int max)
1182 struct device_node *np;
1185 /* default to level-triggered */
1186 memset(senses, IRQ_SENSE_LEVEL | IRQ_POLARITY_NEGATIVE, max - off);
1188 for (np = allnodes; np != 0; np = np->allnext) {
1189 for (j = 0; j < np->n_intrs; j++) {
1190 i = np->intrs[j].line;
1191 if (i >= off && i < max)
1192 senses[i-off] = np->intrs[j].sense;
1198 * Construct and return a list of the device_nodes with a given name.
1200 struct device_node *find_devices(const char *name)
1202 struct device_node *head, **prevp, *np;
1205 for (np = allnodes; np != 0; np = np->allnext) {
1206 if (np->name != 0 && strcasecmp(np->name, name) == 0) {
1214 EXPORT_SYMBOL(find_devices);
1217 * Construct and return a list of the device_nodes with a given type.
1219 struct device_node *find_type_devices(const char *type)
1221 struct device_node *head, **prevp, *np;
1224 for (np = allnodes; np != 0; np = np->allnext) {
1225 if (np->type != 0 && strcasecmp(np->type, type) == 0) {
1233 EXPORT_SYMBOL(find_type_devices);
1236 * Returns all nodes linked together
1238 struct device_node *find_all_nodes(void)
1240 struct device_node *head, **prevp, *np;
1243 for (np = allnodes; np != 0; np = np->allnext) {
1250 EXPORT_SYMBOL(find_all_nodes);
1252 /** Checks if the given "compat" string matches one of the strings in
1253 * the device's "compatible" property
1255 int device_is_compatible(struct device_node *device, const char *compat)
1260 cp = (char *) get_property(device, "compatible", &cplen);
1264 if (strncasecmp(cp, compat, strlen(compat)) == 0)
1273 EXPORT_SYMBOL(device_is_compatible);
1277 * Indicates whether the root node has a given value in its
1278 * compatible property.
1280 int machine_is_compatible(const char *compat)
1282 struct device_node *root;
1285 root = of_find_node_by_path("/");
1287 rc = device_is_compatible(root, compat);
1292 EXPORT_SYMBOL(machine_is_compatible);
1295 * Construct and return a list of the device_nodes with a given type
1296 * and compatible property.
1298 struct device_node *find_compatible_devices(const char *type,
1301 struct device_node *head, **prevp, *np;
1304 for (np = allnodes; np != 0; np = np->allnext) {
1306 && !(np->type != 0 && strcasecmp(np->type, type) == 0))
1308 if (device_is_compatible(np, compat)) {
1316 EXPORT_SYMBOL(find_compatible_devices);
1319 * Find the device_node with a given full_name.
1321 struct device_node *find_path_device(const char *path)
1323 struct device_node *np;
1325 for (np = allnodes; np != 0; np = np->allnext)
1326 if (np->full_name != 0 && strcasecmp(np->full_name, path) == 0)
1330 EXPORT_SYMBOL(find_path_device);
1334 * New implementation of the OF "find" APIs, return a refcounted
1335 * object, call of_node_put() when done. The device tree and list
1336 * are protected by a rw_lock.
1338 * Note that property management will need some locking as well,
1339 * this isn't dealt with yet.
1344 * of_find_node_by_name - Find a node by its "name" property
1345 * @from: The node to start searching from or NULL, the node
1346 * you pass will not be searched, only the next one
1347 * will; typically, you pass what the previous call
1348 * returned. of_node_put() will be called on it
1349 * @name: The name string to match against
1351 * Returns a node pointer with refcount incremented, use
1352 * of_node_put() on it when done.
1354 struct device_node *of_find_node_by_name(struct device_node *from,
1357 struct device_node *np;
1359 read_lock(&devtree_lock);
1360 np = from ? from->allnext : allnodes;
1361 for (; np != 0; np = np->allnext)
1362 if (np->name != 0 && strcasecmp(np->name, name) == 0
1367 read_unlock(&devtree_lock);
1370 EXPORT_SYMBOL(of_find_node_by_name);
1373 * of_find_node_by_type - Find a node by its "device_type" property
1374 * @from: The node to start searching from or NULL, the node
1375 * you pass will not be searched, only the next one
1376 * will; typically, you pass what the previous call
1377 * returned. of_node_put() will be called on it
1378 * @name: The type string to match against
1380 * Returns a node pointer with refcount incremented, use
1381 * of_node_put() on it when done.
1383 struct device_node *of_find_node_by_type(struct device_node *from,
1386 struct device_node *np;
1388 read_lock(&devtree_lock);
1389 np = from ? from->allnext : allnodes;
1390 for (; np != 0; np = np->allnext)
1391 if (np->type != 0 && strcasecmp(np->type, type) == 0
1396 read_unlock(&devtree_lock);
1399 EXPORT_SYMBOL(of_find_node_by_type);
1402 * of_find_compatible_node - Find a node based on type and one of the
1403 * tokens in its "compatible" property
1404 * @from: The node to start searching from or NULL, the node
1405 * you pass will not be searched, only the next one
1406 * will; typically, you pass what the previous call
1407 * returned. of_node_put() will be called on it
1408 * @type: The type string to match "device_type" or NULL to ignore
1409 * @compatible: The string to match to one of the tokens in the device
1410 * "compatible" list.
1412 * Returns a node pointer with refcount incremented, use
1413 * of_node_put() on it when done.
1415 struct device_node *of_find_compatible_node(struct device_node *from,
1416 const char *type, const char *compatible)
1418 struct device_node *np;
1420 read_lock(&devtree_lock);
1421 np = from ? from->allnext : allnodes;
1422 for (; np != 0; np = np->allnext) {
1424 && !(np->type != 0 && strcasecmp(np->type, type) == 0))
1426 if (device_is_compatible(np, compatible) && of_node_get(np))
1431 read_unlock(&devtree_lock);
1434 EXPORT_SYMBOL(of_find_compatible_node);
1437 * of_find_node_by_path - Find a node matching a full OF path
1438 * @path: The full path to match
1440 * Returns a node pointer with refcount incremented, use
1441 * of_node_put() on it when done.
1443 struct device_node *of_find_node_by_path(const char *path)
1445 struct device_node *np = allnodes;
1447 read_lock(&devtree_lock);
1448 for (; np != 0; np = np->allnext) {
1449 if (np->full_name != 0 && strcasecmp(np->full_name, path) == 0
1453 read_unlock(&devtree_lock);
1456 EXPORT_SYMBOL(of_find_node_by_path);
1459 * of_find_node_by_phandle - Find a node given a phandle
1460 * @handle: phandle of the node to find
1462 * Returns a node pointer with refcount incremented, use
1463 * of_node_put() on it when done.
1465 struct device_node *of_find_node_by_phandle(phandle handle)
1467 struct device_node *np;
1469 read_lock(&devtree_lock);
1470 for (np = allnodes; np != 0; np = np->allnext)
1471 if (np->linux_phandle == handle)
1475 read_unlock(&devtree_lock);
1478 EXPORT_SYMBOL(of_find_node_by_phandle);
1481 * of_find_all_nodes - Get next node in global list
1482 * @prev: Previous node or NULL to start iteration
1483 * of_node_put() will be called on it
1485 * Returns a node pointer with refcount incremented, use
1486 * of_node_put() on it when done.
1488 struct device_node *of_find_all_nodes(struct device_node *prev)
1490 struct device_node *np;
1492 read_lock(&devtree_lock);
1493 np = prev ? prev->allnext : allnodes;
1494 for (; np != 0; np = np->allnext)
1495 if (of_node_get(np))
1499 read_unlock(&devtree_lock);
1502 EXPORT_SYMBOL(of_find_all_nodes);
1505 * of_get_parent - Get a node's parent if any
1506 * @node: Node to get parent
1508 * Returns a node pointer with refcount incremented, use
1509 * of_node_put() on it when done.
1511 struct device_node *of_get_parent(const struct device_node *node)
1513 struct device_node *np;
1518 read_lock(&devtree_lock);
1519 np = of_node_get(node->parent);
1520 read_unlock(&devtree_lock);
1523 EXPORT_SYMBOL(of_get_parent);
1526 * of_get_next_child - Iterate a node childs
1527 * @node: parent node
1528 * @prev: previous child of the parent node, or NULL to get first
1530 * Returns a node pointer with refcount incremented, use
1531 * of_node_put() on it when done.
1533 struct device_node *of_get_next_child(const struct device_node *node,
1534 struct device_node *prev)
1536 struct device_node *next;
1538 read_lock(&devtree_lock);
1539 next = prev ? prev->sibling : node->child;
1540 for (; next != 0; next = next->sibling)
1541 if (of_node_get(next))
1545 read_unlock(&devtree_lock);
1548 EXPORT_SYMBOL(of_get_next_child);
1551 * of_node_get - Increment refcount of a node
1552 * @node: Node to inc refcount, NULL is supported to
1553 * simplify writing of callers
1557 struct device_node *of_node_get(struct device_node *node)
1560 kref_get(&node->kref);
1563 EXPORT_SYMBOL(of_node_get);
1565 static inline struct device_node * kref_to_device_node(struct kref *kref)
1567 return container_of(kref, struct device_node, kref);
1571 * of_node_release - release a dynamically allocated node
1572 * @kref: kref element of the node to be released
1574 * In of_node_put() this function is passed to kref_put()
1575 * as the destructor.
1577 static void of_node_release(struct kref *kref)
1579 struct device_node *node = kref_to_device_node(kref);
1580 struct property *prop = node->properties;
1582 if (!OF_IS_DYNAMIC(node))
1585 struct property *next = prop->next;
1592 kfree(node->full_name);
1598 * of_node_put - Decrement refcount of a node
1599 * @node: Node to dec refcount, NULL is supported to
1600 * simplify writing of callers
1603 void of_node_put(struct device_node *node)
1606 kref_put(&node->kref, of_node_release);
1608 EXPORT_SYMBOL(of_node_put);
1611 * Plug a device node into the tree and global list.
1613 void of_attach_node(struct device_node *np)
1615 write_lock(&devtree_lock);
1616 np->sibling = np->parent->child;
1617 np->allnext = allnodes;
1618 np->parent->child = np;
1620 write_unlock(&devtree_lock);
1624 * "Unplug" a node from the device tree. The caller must hold
1625 * a reference to the node. The memory associated with the node
1626 * is not freed until its refcount goes to zero.
1628 void of_detach_node(const struct device_node *np)
1630 struct device_node *parent;
1632 write_lock(&devtree_lock);
1634 parent = np->parent;
1637 allnodes = np->allnext;
1639 struct device_node *prev;
1640 for (prev = allnodes;
1641 prev->allnext != np;
1642 prev = prev->allnext)
1644 prev->allnext = np->allnext;
1647 if (parent->child == np)
1648 parent->child = np->sibling;
1650 struct device_node *prevsib;
1651 for (prevsib = np->parent->child;
1652 prevsib->sibling != np;
1653 prevsib = prevsib->sibling)
1655 prevsib->sibling = np->sibling;
1658 write_unlock(&devtree_lock);
1661 #ifdef CONFIG_PPC_PSERIES
1663 * Fix up the uninitialized fields in a new device node:
1664 * name, type, n_addrs, addrs, n_intrs, intrs, and pci-specific fields
1666 * A lot of boot-time code is duplicated here, because functions such
1667 * as finish_node_interrupts, interpret_pci_props, etc. cannot use the
1670 * This should probably be split up into smaller chunks.
1673 static int of_finish_dynamic_node(struct device_node *node)
1675 struct device_node *parent = of_get_parent(node);
1677 phandle *ibm_phandle;
1679 node->name = get_property(node, "name", NULL);
1680 node->type = get_property(node, "device_type", NULL);
1687 /* We don't support that function on PowerMac, at least
1690 if (_machine == PLATFORM_POWERMAC)
1693 /* fix up new node's linux_phandle field */
1694 if ((ibm_phandle = (unsigned int *)get_property(node,
1695 "ibm,phandle", NULL)))
1696 node->linux_phandle = *ibm_phandle;
1699 of_node_put(parent);
1703 static int prom_reconfig_notifier(struct notifier_block *nb,
1704 unsigned long action, void *node)
1709 case PSERIES_RECONFIG_ADD:
1710 err = of_finish_dynamic_node(node);
1712 finish_node(node, NULL, 0);
1714 printk(KERN_ERR "finish_node returned %d\n", err);
1725 static struct notifier_block prom_reconfig_nb = {
1726 .notifier_call = prom_reconfig_notifier,
1727 .priority = 10, /* This one needs to run first */
1730 static int __init prom_reconfig_setup(void)
1732 return pSeries_reconfig_notifier_register(&prom_reconfig_nb);
1734 __initcall(prom_reconfig_setup);
1738 * Find a property with a given name for a given node
1739 * and return the value.
1741 unsigned char *get_property(struct device_node *np, const char *name,
1744 struct property *pp;
1746 for (pp = np->properties; pp != 0; pp = pp->next)
1747 if (strcmp(pp->name, name) == 0) {
1754 EXPORT_SYMBOL(get_property);
1757 * Add a property to a node
1759 int prom_add_property(struct device_node* np, struct property* prop)
1761 struct property **next;
1764 write_lock(&devtree_lock);
1765 next = &np->properties;
1767 if (strcmp(prop->name, (*next)->name) == 0) {
1768 /* duplicate ! don't insert it */
1769 write_unlock(&devtree_lock);
1772 next = &(*next)->next;
1775 write_unlock(&devtree_lock);
1777 #ifdef CONFIG_PROC_DEVICETREE
1778 /* try to add to proc as well if it was initialized */
1780 proc_device_tree_add_prop(np->pde, prop);
1781 #endif /* CONFIG_PROC_DEVICETREE */