1/* SPDX-License-Identifier: GPL-2.0+ OR BSD-2-Clause */
2/*
3 * pylibfdt - Flat Device Tree manipulation in Python
4 * Copyright (C) 2017 Google, Inc.
5 * Written by Simon Glass <sjg@chromium.org>
6 */
7
8%module libfdt
9
10%include <stdint.i>
11
12%{
13#define SWIG_FILE_WITH_INIT
14#include "libfdt.h"
15
16/*
17 * We rename this function here to avoid problems with swig, since we also have
18 * a struct called fdt_property. That struct causes swig to create a class in
19 * libfdt.py called fdt_property(), which confuses things.
20 */
21static int fdt_property_stub(void *fdt, const char *name, const char *val,
22                             int len)
23{
24    return fdt_property(fdt, name, val, len);
25}
26
27%}
28
29%pythoncode %{
30
31import struct
32
33# Error codes, corresponding to FDT_ERR_... in libfdt.h
34(NOTFOUND,
35        EXISTS,
36        NOSPACE,
37        BADOFFSET,
38        BADPATH,
39        BADPHANDLE,
40        BADSTATE,
41        TRUNCATED,
42        BADMAGIC,
43        BADVERSION,
44        BADSTRUCTURE,
45        BADLAYOUT,
46        INTERNAL,
47        BADNCELLS,
48        BADVALUE,
49        BADOVERLAY,
50        NOPHANDLES) = QUIET_ALL = range(1, 18)
51# QUIET_ALL can be passed as the 'quiet' parameter to avoid exceptions
52# altogether. All # functions passed this value will return an error instead
53# of raising an exception.
54
55# Pass this as the 'quiet' parameter to return -ENOTFOUND on NOTFOUND errors,
56# instead of raising an exception.
57QUIET_NOTFOUND = (NOTFOUND,)
58QUIET_NOSPACE = (NOSPACE,)
59
60
61class FdtException(Exception):
62    """An exception caused by an error such as one of the codes above"""
63    def __init__(self, err):
64        self.err = err
65
66    def __str__(self):
67        return 'pylibfdt error %d: %s' % (self.err, fdt_strerror(self.err))
68
69def strerror(fdt_err):
70    """Get the string for an error number
71
72    Args:
73        fdt_err: Error number (-ve)
74
75    Returns:
76        String containing the associated error
77    """
78    return fdt_strerror(fdt_err)
79
80def check_err(val, quiet=()):
81    """Raise an error if the return value is -ve
82
83    This is used to check for errors returned by libfdt C functions.
84
85    Args:
86        val: Return value from a libfdt function
87        quiet: Errors to ignore (empty to raise on all errors)
88
89    Returns:
90        val if val >= 0
91
92    Raises
93        FdtException if val < 0
94    """
95    if val < 0:
96        if -val not in quiet:
97            raise FdtException(val)
98    return val
99
100def check_err_null(val, quiet=()):
101    """Raise an error if the return value is NULL
102
103    This is used to check for a NULL return value from certain libfdt C
104    functions
105
106    Args:
107        val: Return value from a libfdt function
108        quiet: Errors to ignore (empty to raise on all errors)
109
110    Returns:
111        val if val is a list, None if not
112
113    Raises
114        FdtException if val indicates an error was reported and the error
115        is not in @quiet.
116    """
117    # Normally a list is returned which contains the data and its length.
118    # If we get just an integer error code, it means the function failed.
119    if not isinstance(val, list):
120        if -val not in quiet:
121            raise FdtException(val)
122    return val
123
124class FdtRo(object):
125    """Class for a read-only device-tree
126
127    This is a base class used by FdtRw (read-write access) and FdtSw
128    (sequential-write access). It implements read-only access to the
129    device tree.
130
131    Here are the three classes and when you should use them:
132
133        FdtRo - read-only access to an existing FDT
134        FdtRw - read-write access to an existing FDT (most common case)
135        FdtSw - for creating a new FDT, as well as allowing read-only access
136    """
137    def __init__(self, data):
138        self._fdt = bytearray(data)
139        check_err(fdt_check_header(self._fdt));
140
141    def as_bytearray(self):
142        """Get the device tree contents as a bytearray
143
144        This can be passed directly to libfdt functions that access a
145        const void * for the device tree.
146
147        Returns:
148            bytearray containing the device tree
149        """
150        return bytearray(self._fdt)
151
152    def next_node(self, nodeoffset, depth, quiet=()):
153        """Find the next subnode
154
155        Args:
156            nodeoffset: Node offset of previous node
157            depth: The depth of the node at nodeoffset. This is used to
158                calculate the depth of the returned node
159            quiet: Errors to ignore (empty to raise on all errors)
160
161        Returns:
162            Typle:
163                Offset of the next node, if any, else a -ve error
164                Depth of the returned node, if any, else undefined
165
166        Raises:
167            FdtException if no more nodes found or other error occurs
168        """
169        return check_err(fdt_next_node(self._fdt, nodeoffset, depth), quiet)
170
171    def first_subnode(self, nodeoffset, quiet=()):
172        """Find the first subnode of a parent node
173
174        Args:
175            nodeoffset: Node offset of parent node
176            quiet: Errors to ignore (empty to raise on all errors)
177
178        Returns:
179            The offset of the first subnode, if any
180
181        Raises:
182            FdtException if no subnodes found or other error occurs
183        """
184        return check_err(fdt_first_subnode(self._fdt, nodeoffset), quiet)
185
186    def next_subnode(self, nodeoffset, quiet=()):
187        """Find the next subnode
188
189        Args:
190            nodeoffset: Node offset of previous subnode
191            quiet: Errors to ignore (empty to raise on all errors)
192
193        Returns:
194            The offset of the next subnode, if any
195
196        Raises:
197            FdtException if no more subnodes found or other error occurs
198        """
199        return check_err(fdt_next_subnode(self._fdt, nodeoffset), quiet)
200
201    def magic(self):
202        """Return the magic word from the header
203
204        Returns:
205            Magic word
206        """
207        return fdt_magic(self._fdt)
208
209    def totalsize(self):
210        """Return the total size of the device tree
211
212        Returns:
213            Total tree size in bytes
214        """
215        return fdt_totalsize(self._fdt)
216
217    def off_dt_struct(self):
218        """Return the start of the device-tree struct area
219
220        Returns:
221            Start offset of struct area
222        """
223        return fdt_off_dt_struct(self._fdt)
224
225    def off_dt_strings(self):
226        """Return the start of the device-tree string area
227
228        Returns:
229            Start offset of string area
230        """
231        return fdt_off_dt_strings(self._fdt)
232
233    def off_mem_rsvmap(self):
234        """Return the start of the memory reserve map
235
236        Returns:
237            Start offset of memory reserve map
238        """
239        return fdt_off_mem_rsvmap(self._fdt)
240
241    def version(self):
242        """Return the version of the device tree
243
244        Returns:
245            Version number of the device tree
246        """
247        return fdt_version(self._fdt)
248
249    def last_comp_version(self):
250        """Return the last compatible version of the device tree
251
252        Returns:
253            Last compatible version number of the device tree
254        """
255        return fdt_last_comp_version(self._fdt)
256
257    def boot_cpuid_phys(self):
258        """Return the physical boot CPU ID
259
260        Returns:
261            Physical boot CPU ID
262        """
263        return fdt_boot_cpuid_phys(self._fdt)
264
265    def size_dt_strings(self):
266        """Return the start of the device-tree string area
267
268        Returns:
269            Start offset of string area
270        """
271        return fdt_size_dt_strings(self._fdt)
272
273    def size_dt_struct(self):
274        """Return the start of the device-tree struct area
275
276        Returns:
277            Start offset of struct area
278        """
279        return fdt_size_dt_struct(self._fdt)
280
281    def num_mem_rsv(self, quiet=()):
282        """Return the number of memory reserve-map records
283
284        Returns:
285            Number of memory reserve-map records
286        """
287        return check_err(fdt_num_mem_rsv(self._fdt), quiet)
288
289    def get_mem_rsv(self, index, quiet=()):
290        """Return the indexed memory reserve-map record
291
292        Args:
293            index: Record to return (0=first)
294
295        Returns:
296            Number of memory reserve-map records
297        """
298        return check_err(fdt_get_mem_rsv(self._fdt, index), quiet)
299
300    def subnode_offset(self, parentoffset, name, quiet=()):
301        """Get the offset of a named subnode
302
303        Args:
304            parentoffset: Offset of the parent node to check
305            name: Name of the required subnode, e.g. 'subnode@1'
306            quiet: Errors to ignore (empty to raise on all errors)
307
308        Returns:
309            The node offset of the found node, if any
310
311        Raises
312            FdtException if there is no node with that name, or other error
313        """
314        return check_err(fdt_subnode_offset(self._fdt, parentoffset, name),
315                         quiet)
316
317    def path_offset(self, path, quiet=()):
318        """Get the offset for a given path
319
320        Args:
321            path: Path to the required node, e.g. '/node@3/subnode@1'
322            quiet: Errors to ignore (empty to raise on all errors)
323
324        Returns:
325            Node offset
326
327        Raises
328            FdtException if the path is not valid or not found
329        """
330        return check_err(fdt_path_offset(self._fdt, path), quiet)
331
332    def get_name(self, nodeoffset):
333        """Get the name of a node
334
335        Args:
336            nodeoffset: Offset of node to check
337
338        Returns:
339            Node name
340
341        Raises:
342            FdtException on error (e.g. nodeoffset is invalid)
343        """
344        return check_err_null(fdt_get_name(self._fdt, nodeoffset))[0]
345
346    def first_property_offset(self, nodeoffset, quiet=()):
347        """Get the offset of the first property in a node offset
348
349        Args:
350            nodeoffset: Offset to the node to check
351            quiet: Errors to ignore (empty to raise on all errors)
352
353        Returns:
354            Offset of the first property
355
356        Raises
357            FdtException if the associated node has no properties, or some
358                other error occurred
359        """
360        return check_err(fdt_first_property_offset(self._fdt, nodeoffset),
361                         quiet)
362
363    def next_property_offset(self, prop_offset, quiet=()):
364        """Get the next property in a node
365
366        Args:
367            prop_offset: Offset of the previous property
368            quiet: Errors to ignore (empty to raise on all errors)
369
370        Returns:
371            Offset of the next property
372
373        Raises:
374            FdtException if the associated node has no more properties, or
375                some other error occurred
376        """
377        return check_err(fdt_next_property_offset(self._fdt, prop_offset),
378                         quiet)
379
380    def get_property_by_offset(self, prop_offset, quiet=()):
381        """Obtains a property that can be examined
382
383        Args:
384            prop_offset: Offset of property (e.g. from first_property_offset())
385            quiet: Errors to ignore (empty to raise on all errors)
386
387        Returns:
388            Property object, or None if not found
389
390        Raises:
391            FdtException on error (e.g. invalid prop_offset or device
392            tree format)
393        """
394        pdata = check_err_null(
395                fdt_get_property_by_offset(self._fdt, prop_offset), quiet)
396        if isinstance(pdata, (int)):
397            return pdata
398        return Property(pdata[0], pdata[1])
399
400    def getprop(self, nodeoffset, prop_name, quiet=()):
401        """Get a property from a node
402
403        Args:
404            nodeoffset: Node offset containing property to get
405            prop_name: Name of property to get
406            quiet: Errors to ignore (empty to raise on all errors)
407
408        Returns:
409            Value of property as a Property object (which can be used as a
410               bytearray/string), or -ve error number. On failure, returns an
411               integer error
412
413        Raises:
414            FdtError if any error occurs (e.g. the property is not found)
415        """
416        pdata = check_err_null(fdt_getprop(self._fdt, nodeoffset, prop_name),
417                               quiet)
418        if isinstance(pdata, (int)):
419            return pdata
420        return Property(prop_name, bytearray(pdata[0]))
421
422    def get_phandle(self, nodeoffset):
423        """Get the phandle of a node
424
425        Args:
426            nodeoffset: Node offset to check
427
428        Returns:
429            phandle of node, or 0 if the node has no phandle or another error
430            occurs
431        """
432        return fdt_get_phandle(self._fdt, nodeoffset)
433
434    def parent_offset(self, nodeoffset, quiet=()):
435        """Get the offset of a node's parent
436
437        Args:
438            nodeoffset: Node offset to check
439            quiet: Errors to ignore (empty to raise on all errors)
440
441        Returns:
442            The offset of the parent node, if any
443
444        Raises:
445            FdtException if no parent found or other error occurs
446        """
447        return check_err(fdt_parent_offset(self._fdt, nodeoffset), quiet)
448
449    def node_offset_by_phandle(self, phandle, quiet=()):
450        """Get the offset of a node with the given phandle
451
452        Args:
453            phandle: Phandle to search for
454            quiet: Errors to ignore (empty to raise on all errors)
455
456        Returns:
457            The offset of node with that phandle, if any
458
459        Raises:
460            FdtException if no node found or other error occurs
461        """
462        return check_err(fdt_node_offset_by_phandle(self._fdt, phandle), quiet)
463
464
465class Fdt(FdtRo):
466    """Device tree class, supporting all operations
467
468    The Fdt object is created is created from a device tree binary file,
469    e.g. with something like:
470
471       fdt = Fdt(open("filename.dtb").read())
472
473    Operations can then be performed using the methods in this class. Each
474    method xxx(args...) corresponds to a libfdt function fdt_xxx(fdt, args...).
475
476    All methods raise an FdtException if an error occurs. To avoid this
477    behaviour a 'quiet' parameter is provided for some functions. This
478    defaults to empty, but you can pass a list of errors that you expect.
479    If one of these errors occurs, the function will return an error number
480    (e.g. -NOTFOUND).
481    """
482    def __init__(self, data):
483        FdtRo.__init__(self, data)
484
485    @staticmethod
486    def create_empty_tree(size, quiet=()):
487        """Create an empty device tree ready for use
488
489        Args:
490            size: Size of device tree in bytes
491
492        Returns:
493            Fdt object containing the device tree
494        """
495        data = bytearray(size)
496        err = check_err(fdt_create_empty_tree(data, size), quiet)
497        if err:
498            return err
499        return Fdt(data)
500
501    def resize(self, size, quiet=()):
502        """Move the device tree into a larger or smaller space
503
504        This creates a new device tree of size @size and moves the existing
505        device tree contents over to that. It can be used to create more space
506        in a device tree. Note that the Fdt object remains the same, but it
507        now has a new bytearray holding the contents.
508
509        Args:
510            size: Required new size of device tree in bytes
511        """
512        fdt = bytearray(size)
513        err = check_err(fdt_open_into(self._fdt, fdt, size), quiet)
514        if err:
515            return err
516        self._fdt = fdt
517
518    def pack(self, quiet=()):
519        """Pack the device tree to remove unused space
520
521        This adjusts the tree in place.
522
523        Args:
524            quiet: Errors to ignore (empty to raise on all errors)
525
526        Returns:
527            Error code, or 0 if OK
528
529        Raises:
530            FdtException if any error occurs
531        """
532        err = check_err(fdt_pack(self._fdt), quiet)
533        if err:
534            return err
535        del self._fdt[self.totalsize():]
536        return err
537
538    def set_name(self, nodeoffset, name, quiet=()):
539        """Set the name of a node
540
541        Args:
542            nodeoffset: Node offset of node to update
543            name: New node name (string without \0)
544
545        Returns:
546            Error code, or 0 if OK
547
548        Raises:
549            FdtException if no parent found or other error occurs
550        """
551        if chr(0) in name:
552            raise ValueError('Property contains embedded nul characters')
553        return check_err(fdt_set_name(self._fdt, nodeoffset, name), quiet)
554
555    def setprop(self, nodeoffset, prop_name, val, quiet=()):
556        """Set the value of a property
557
558        Args:
559            nodeoffset: Node offset containing the property to create/update
560            prop_name: Name of property
561            val: Value to write (string or bytearray)
562            quiet: Errors to ignore (empty to raise on all errors)
563
564        Returns:
565            Error code, or 0 if OK
566
567        Raises:
568            FdtException if no parent found or other error occurs
569        """
570        return check_err(fdt_setprop(self._fdt, nodeoffset, prop_name, val,
571                                     len(val)), quiet)
572
573    def setprop_u32(self, nodeoffset, prop_name, val, quiet=()):
574        """Set the value of a property
575
576        Args:
577            nodeoffset: Node offset containing the property to create/update
578            prop_name: Name of property
579            val: Value to write (integer)
580            quiet: Errors to ignore (empty to raise on all errors)
581
582        Returns:
583            Error code, or 0 if OK
584
585        Raises:
586            FdtException if no parent found or other error occurs
587        """
588        return check_err(fdt_setprop_u32(self._fdt, nodeoffset, prop_name, val),
589                         quiet)
590
591    def setprop_u64(self, nodeoffset, prop_name, val, quiet=()):
592        """Set the value of a property
593
594        Args:
595            nodeoffset: Node offset containing the property to create/update
596            prop_name: Name of property
597            val: Value to write (integer)
598            quiet: Errors to ignore (empty to raise on all errors)
599
600        Returns:
601            Error code, or 0 if OK
602
603        Raises:
604            FdtException if no parent found or other error occurs
605        """
606        return check_err(fdt_setprop_u64(self._fdt, nodeoffset, prop_name, val),
607                         quiet)
608
609    def setprop_str(self, nodeoffset, prop_name, val, quiet=()):
610        """Set the string value of a property
611
612        The property is set to the string, with a nul terminator added
613
614        Args:
615            nodeoffset: Node offset containing the property to create/update
616            prop_name: Name of property
617            val: Value to write (string without nul terminator). Unicode is
618                supposed by encoding to UTF-8
619            quiet: Errors to ignore (empty to raise on all errors)
620
621        Returns:
622            Error code, or 0 if OK
623
624        Raises:
625            FdtException if no parent found or other error occurs
626        """
627        val = val.encode('utf-8') + '\0'
628        return check_err(fdt_setprop(self._fdt, nodeoffset, prop_name,
629                                     val, len(val)), quiet)
630
631    def delprop(self, nodeoffset, prop_name):
632        """Delete a property from a node
633
634        Args:
635            nodeoffset: Node offset containing property to delete
636            prop_name: Name of property to delete
637
638        Raises:
639            FdtError if the property does not exist, or another error occurs
640        """
641        return check_err(fdt_delprop(self._fdt, nodeoffset, prop_name))
642
643    def del_node(self, nodeoffset):
644        """Delete a node
645
646        Args:
647            nodeoffset: Node offset containing property to delete
648
649        Raises:
650            FdtError if the node does not exist, or another error occurs
651        """
652        return check_err(fdt_del_node(self._fdt, nodeoffset))
653
654
655class Property(bytearray):
656    """Holds a device tree property name and value.
657
658    This holds a copy of a property taken from the device tree. It does not
659    reference the device tree, so if anything changes in the device tree,
660    a Property object will remain valid.
661
662    Properties:
663        name: Property name
664        value: Property value as a bytearray
665    """
666    def __init__(self, name, value):
667        bytearray.__init__(self, value)
668        self.name = name
669
670    def as_cell(self, fmt):
671        return struct.unpack('>' + fmt, self)[0]
672
673    def as_uint32(self):
674        return self.as_cell('L')
675
676    def as_int32(self):
677        return self.as_cell('l')
678
679    def as_uint64(self):
680        return self.as_cell('Q')
681
682    def as_int64(self):
683        return self.as_cell('q')
684
685    def as_str(self):
686        """Unicode is supported by decoding from UTF-8"""
687        if self[-1] != 0:
688            raise ValueError('Property lacks nul termination')
689        if 0 in self[:-1]:
690            raise ValueError('Property contains embedded nul characters')
691        return self[:-1].decode('utf-8')
692
693
694class FdtSw(FdtRo):
695    """Software interface to create a device tree from scratch
696
697    The methods in this class work by adding to an existing 'partial' device
698    tree buffer of a fixed size created by instantiating this class. When the
699    tree is complete, call as_fdt() to obtain a device tree ready to be used.
700
701    Similarly with nodes, a new node is started with begin_node() and finished
702    with end_node().
703
704    The context manager functions can be used to make this a bit easier:
705
706    # First create the device tree with a node and property:
707    sw = FdtSw()
708    with sw.add_node('node'):
709        sw.property_u32('reg', 2)
710    fdt = sw.as_fdt()
711
712    # Now we can use it as a real device tree
713    fdt.setprop_u32(0, 'reg', 3)
714
715    The size hint provides a starting size for the space to be used by the
716    device tree. This will be increased automatically as needed as new items
717    are added to the tree.
718    """
719    INC_SIZE = 1024  # Expand size by this much when out of space
720
721    def __init__(self, size_hint=None):
722        """Create a new FdtSw object
723
724        Args:
725            size_hint: A hint as to the initial size to use
726
727        Raises:
728            ValueError if size_hint is negative
729
730        Returns:
731            FdtSw object on success, else integer error code (if not raising)
732        """
733        if not size_hint:
734            size_hint = self.INC_SIZE
735        fdtsw = bytearray(size_hint)
736        err = check_err(fdt_create(fdtsw, size_hint))
737        if err:
738            return err
739        self._fdt = fdtsw
740
741    def as_fdt(self):
742        """Convert a FdtSw into an Fdt so it can be accessed as normal
743
744        Creates a new Fdt object from the work-in-progress device tree. This
745        does not call fdt_finish() on the current object, so it is possible to
746        add more nodes/properties and call as_fdt() again to get an updated
747        tree.
748
749        Returns:
750            Fdt object allowing access to the newly created device tree
751        """
752        fdtsw = bytearray(self._fdt)
753        check_err(fdt_finish(fdtsw))
754        return Fdt(fdtsw)
755
756    def check_space(self, val):
757        """Check if we need to add more space to the FDT
758
759        This should be called with the error code from an operation. If this is
760        -NOSPACE then the FDT will be expanded to have more space, and True will
761        be returned, indicating that the operation needs to be tried again.
762
763        Args:
764            val: Return value from the operation that was attempted
765
766        Returns:
767            True if the operation must be retried, else False
768        """
769        if check_err(val, QUIET_NOSPACE) < 0:
770            self.resize(len(self._fdt) + self.INC_SIZE)
771            return True
772        return False
773
774    def resize(self, size):
775        """Resize the buffer to accommodate a larger tree
776
777        Args:
778            size: New size of tree
779
780        Raises:
781            FdtException on any error
782        """
783        fdt = bytearray(size)
784        err = check_err(fdt_resize(self._fdt, fdt, size))
785        self._fdt = fdt
786
787    def add_reservemap_entry(self, addr, size):
788        """Add a new memory reserve map entry
789
790        Once finished adding, you must call finish_reservemap().
791
792        Args:
793            addr: 64-bit start address
794            size: 64-bit size
795
796        Raises:
797            FdtException on any error
798        """
799        while self.check_space(fdt_add_reservemap_entry(self._fdt, addr,
800                                                        size)):
801            pass
802
803    def finish_reservemap(self):
804        """Indicate that there are no more reserve map entries to add
805
806        Raises:
807            FdtException on any error
808        """
809        while self.check_space(fdt_finish_reservemap(self._fdt)):
810            pass
811
812    def begin_node(self, name):
813        """Begin a new node
814
815        Use this before adding properties to the node. Then call end_node() to
816        finish it. You can also use the context manager as shown in the FdtSw
817        class comment.
818
819        Args:
820            name: Name of node to begin
821
822        Raises:
823            FdtException on any error
824        """
825        while self.check_space(fdt_begin_node(self._fdt, name)):
826            pass
827
828    def property_string(self, name, string):
829        """Add a property with a string value
830
831        The string will be nul-terminated when written to the device tree
832
833        Args:
834            name: Name of property to add
835            string: String value of property
836
837        Raises:
838            FdtException on any error
839        """
840        while self.check_space(fdt_property_string(self._fdt, name, string)):
841            pass
842
843    def property_u32(self, name, val):
844        """Add a property with a 32-bit value
845
846        Write a single-cell value to the device tree
847
848        Args:
849            name: Name of property to add
850            val: Value of property
851
852        Raises:
853            FdtException on any error
854        """
855        while self.check_space(fdt_property_u32(self._fdt, name, val)):
856            pass
857
858    def property_u64(self, name, val):
859        """Add a property with a 64-bit value
860
861        Write a double-cell value to the device tree in big-endian format
862
863        Args:
864            name: Name of property to add
865            val: Value of property
866
867        Raises:
868            FdtException on any error
869        """
870        while self.check_space(fdt_property_u64(self._fdt, name, val)):
871            pass
872
873    def property_cell(self, name, val):
874        """Add a property with a single-cell value
875
876        Write a single-cell value to the device tree
877
878        Args:
879            name: Name of property to add
880            val: Value of property
881            quiet: Errors to ignore (empty to raise on all errors)
882
883        Raises:
884            FdtException on any error
885        """
886        while self.check_space(fdt_property_cell(self._fdt, name, val)):
887            pass
888
889    def property(self, name, val):
890        """Add a property
891
892        Write a new property with the given value to the device tree. The value
893        is taken as is and is not nul-terminated
894
895        Args:
896            name: Name of property to add
897            val: Value of property
898            quiet: Errors to ignore (empty to raise on all errors)
899
900        Raises:
901            FdtException on any error
902        """
903        while self.check_space(fdt_property_stub(self._fdt, name, val,
904                                                 len(val))):
905            pass
906
907    def end_node(self):
908        """End a node
909
910        Use this after adding properties to a node to close it off. You can also
911        use the context manager as shown in the FdtSw class comment.
912
913        Args:
914            quiet: Errors to ignore (empty to raise on all errors)
915
916        Raises:
917            FdtException on any error
918        """
919        while self.check_space(fdt_end_node(self._fdt)):
920            pass
921
922    def add_node(self, name):
923        """Create a new context for adding a node
924
925        When used in a 'with' clause this starts a new node and finishes it
926        afterward.
927
928        Args:
929            name: Name of node to add
930        """
931        return NodeAdder(self, name)
932
933
934class NodeAdder():
935    """Class to provide a node context
936
937    This allows you to add nodes in a more natural way:
938
939        with fdtsw.add_node('name'):
940            fdtsw.property_string('test', 'value')
941
942    The node is automatically completed with a call to end_node() when the
943    context exits.
944    """
945    def __init__(self, fdtsw, name):
946        self._fdt = fdtsw
947        self._name = name
948
949    def __enter__(self):
950        self._fdt.begin_node(self._name)
951
952    def __exit__(self, type, value, traceback):
953        self._fdt.end_node()
954%}
955
956%rename(fdt_property) fdt_property_func;
957
958/*
959 * fdt32_t is a big-endian 32-bit value defined to uint32_t in libfdt_env.h
960 * so use the same type here.
961 */
962typedef uint32_t fdt32_t;
963
964%include "libfdt/fdt.h"
965
966%include "typemaps.i"
967
968/* Most functions don't change the device tree, so use a const void * */
969%typemap(in) (const void *)(const void *fdt) {
970	if (!PyByteArray_Check($input)) {
971		SWIG_exception_fail(SWIG_TypeError, "in method '" "$symname"
972			"', argument " "$argnum"" of type '" "$type""'");
973	}
974	$1 = (void *)PyByteArray_AsString($input);
975        fdt = $1;
976        fdt = fdt; /* avoid unused variable warning */
977}
978
979/* Some functions do change the device tree, so use void * */
980%typemap(in) (void *)(const void *fdt) {
981	if (!PyByteArray_Check($input)) {
982		SWIG_exception_fail(SWIG_TypeError, "in method '" "$symname"
983			"', argument " "$argnum"" of type '" "$type""'");
984	}
985	$1 = PyByteArray_AsString($input);
986        fdt = $1;
987        fdt = fdt; /* avoid unused variable warning */
988}
989
990/* typemap used for fdt_get_property_by_offset() */
991%typemap(out) (struct fdt_property *) {
992	PyObject *buff;
993
994	if ($1) {
995		resultobj = PyString_FromString(
996			fdt_string(fdt1, fdt32_to_cpu($1->nameoff)));
997		buff = PyByteArray_FromStringAndSize(
998			(const char *)($1 + 1), fdt32_to_cpu($1->len));
999		resultobj = SWIG_Python_AppendOutput(resultobj, buff);
1000	}
1001}
1002
1003%apply int *OUTPUT { int *lenp };
1004
1005/* typemap used for fdt_getprop() */
1006%typemap(out) (const void *) {
1007	if (!$1)
1008		$result = Py_None;
1009	else
1010		$result = Py_BuildValue("s#", $1, *arg4);
1011}
1012
1013/* typemap used for fdt_setprop() */
1014%typemap(in) (const void *val) {
1015    $1 = PyString_AsString($input);   /* char *str */
1016}
1017
1018/* typemap used for fdt_add_reservemap_entry() */
1019%typemap(in) uint64_t {
1020   $1 = PyLong_AsUnsignedLong($input);
1021}
1022
1023/* typemaps used for fdt_next_node() */
1024%typemap(in, numinputs=1) int *depth (int depth) {
1025   depth = (int) PyInt_AsLong($input);
1026   $1 = &depth;
1027}
1028
1029%typemap(argout) int *depth {
1030        PyObject *val = Py_BuildValue("i", *arg$argnum);
1031        resultobj = SWIG_Python_AppendOutput(resultobj, val);
1032}
1033
1034%apply int *depth { int *depth };
1035
1036/* typemaps for fdt_get_mem_rsv */
1037%typemap(in, numinputs=0) uint64_t * (uint64_t temp) {
1038   $1 = &temp;
1039}
1040
1041%typemap(argout) uint64_t * {
1042        PyObject *val = PyLong_FromUnsignedLong(*arg$argnum);
1043        if (!result) {
1044           if (PyTuple_GET_SIZE(resultobj) == 0)
1045              resultobj = val;
1046           else
1047              resultobj = SWIG_Python_AppendOutput(resultobj, val);
1048        }
1049}
1050
1051/* We have both struct fdt_property and a function fdt_property() */
1052%warnfilter(302) fdt_property;
1053
1054/* These are macros in the header so have to be redefined here */
1055uint32_t fdt_magic(const void *fdt);
1056uint32_t fdt_totalsize(const void *fdt);
1057uint32_t fdt_off_dt_struct(const void *fdt);
1058uint32_t fdt_off_dt_strings(const void *fdt);
1059uint32_t fdt_off_mem_rsvmap(const void *fdt);
1060uint32_t fdt_version(const void *fdt);
1061uint32_t fdt_last_comp_version(const void *fdt);
1062uint32_t fdt_boot_cpuid_phys(const void *fdt);
1063uint32_t fdt_size_dt_strings(const void *fdt);
1064uint32_t fdt_size_dt_struct(const void *fdt);
1065
1066int fdt_property_string(void *fdt, const char *name, const char *val);
1067int fdt_property_cell(void *fdt, const char *name, uint32_t val);
1068
1069/*
1070 * This function has a stub since the name fdt_property is used for both a
1071  * function and a struct, which confuses SWIG.
1072 */
1073int fdt_property_stub(void *fdt, const char *name, const char *val, int len);
1074
1075%include <../libfdt/libfdt.h>
1076