backport Python3 support

.github/workflows/custom.yml

@@ -89,14 +89,7 @@ jobs:
       - name: Install essential packages
         run: |
           sudo apt-get update
-          sudo apt-get install swig
-          echo 'switch to python2 as default'
-          sudo rm /usr/bin/python
-          wget https://www.python.org/ftp/python/2.7.18/Python-2.7.18.tar.xz
-          tar -xJf Python-2.7.18.tar.xz
-          cd Python-2.7.18
-          ./configure && sudo make && sudo make install
-          sudo ln -s /usr/bin/python2 /usr/bin/python
+          sudo apt-get install swig python3-dev
 
       - name: Download OpenWrt toolchain
         run: |

scripts/dtc/README

@@ -0,0 +1,106 @@
+The source tree contains the Device Tree Compiler (dtc) toolchain for
+working with device tree source and binary files and also libfdt, a
+utility library for reading and manipulating the binary format.
+
+DTC and LIBFDT are maintained by:
+
+David Gibson <david@gibson.dropbear.id.au>
+Jon Loeliger <loeliger@gmail.com>
+
+
+Python library
+--------------
+
+A Python library is also available. To build this you will need to install
+swig and Python development files. On Debian distributions:
+
+   sudo apt-get install swig python3-dev
+
+The library provides an Fdt class which you can use like this:
+
+$ PYTHONPATH=../pylibfdt python3
+>>> import libfdt
+>>> fdt = libfdt.Fdt(open('test_tree1.dtb', mode='rb').read())
+>>> node = fdt.path_offset('/subnode@1')
+>>> print(node)
+124
+>>> prop_offset = fdt.first_property_offset(node)
+>>> prop = fdt.get_property_by_offset(prop_offset)
+>>> print('%s=%s' % (prop.name, prop.as_str()))
+compatible=subnode1
+>>> node2 = fdt.path_offset('/')
+>>> print(fdt.getprop(node2, 'compatible').as_str())
+test_tree1
+
+You will find tests in tests/pylibfdt_tests.py showing how to use each
+method. Help is available using the Python help command, e.g.:
+
+    $ cd pylibfdt
+    $ python3 -c "import libfdt; help(libfdt)"
+
+If you add new features, please check code coverage:
+
+    $ sudo apt-get install python3-coverage
+    $ cd tests
+    # It's just 'coverage' on most other distributions
+    $ python3-coverage run pylibfdt_tests.py
+    $ python3-coverage html
+    # Open 'htmlcov/index.html' in your browser
+
+
+The library can be installed with pip from a local source tree:
+
+    pip install . [--user|--prefix=/path/to/install_dir]
+
+Or directly from a remote git repo:
+
+    pip install git+git://git.kernel.org/pub/scm/utils/dtc/dtc.git@main
+
+The install depends on libfdt shared library being installed on the host system
+first. Generally, using --user or --prefix is not necessary and pip will use the
+default location for the Python installation which varies if the user is root or
+not.
+
+You can also install everything via make if you like, but pip is recommended.
+
+To install both libfdt and pylibfdt you can use:
+
+    make install [PREFIX=/path/to/install_dir]
+
+To disable building the python library, even if swig and Python are available,
+use:
+
+    make NO_PYTHON=1
+
+
+More work remains to support all of libfdt, including access to numeric
+values.
+
+
+Adding a new function to libfdt.h
+---------------------------------
+
+The shared library uses libfdt/version.lds to list the exported functions, so
+add your new function there. Check that your function works with pylibfdt. If
+it cannot be supported, put the declaration in libfdt.h behind #ifndef SWIG so
+that swig ignores it.
+
+
+Tests
+-----
+
+Test files are kept in the tests/ directory. Use 'make check' to build and run
+all tests.
+
+If you want to adjust a test file, be aware that tree_tree1.dts is compiled
+and checked against a binary tree from assembler macros in trees.S. So
+if you change that file you must change tree.S also.
+
+
+Mailing list
+------------
+The following list is for discussion about dtc and libfdt implementation
+mailto:devicetree-compiler@vger.kernel.org
+
+Core device tree bindings are discussed on the devicetree-spec list:
+mailto:devicetree-spec@vger.kernel.org

scripts/dtc/pylibfdt/Makefile

@@ -13,19 +13,32 @@ include $(LIBFDT_srcdir)/Makefile.libfdt
 PYLIBFDT_srcs = $(addprefix $(LIBFDT_srcdir)/,$(LIBFDT_SRCS)) \
 		$(obj)/libfdt.i
 
+# create a version string compliant with PEP 440
+PEP_VERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(subst -,,$(EXTRAVERSION))
+
 quiet_cmd_pymod = PYMOD   $@
       cmd_pymod = unset CROSS_COMPILE; unset CFLAGS; \
 		CC="$(HOSTCC)" LDSHARED="$(HOSTCC) -shared " \
 		LDFLAGS="$(HOSTLDFLAGS)" \
-		VERSION="u-boot-$(UBOOTVERSION)" \
+		VERSION="$(PEP_VERSION)" \
 		CPPFLAGS="$(HOSTCFLAGS) -I$(LIBFDT_srcdir)" OBJDIR=$(obj) \
 		SOURCES="$(PYLIBFDT_srcs)" \
 		SWIG_OPTS="-I$(LIBFDT_srcdir) -I$(LIBFDT_srcdir)/.." \
-		$(PYTHON) $< --quiet build_ext --inplace
+		$(PYTHON3) $< --quiet build_ext --inplace
 
-$(obj)/_libfdt.so: $(src)/setup.py $(PYLIBFDT_srcs) FORCE
+rebuild: $(src)/setup.py $(PYLIBFDT_srcs)
+	@# Remove the library since otherwise Python doesn't seem to regenerate
+	@# the libfdt.py file if it is missing.
+	@rm -f $(obj)/_libfdt*.so
 	$(call if_changed,pymod)
+	@# Rename the file to _libfdt.so so this Makefile doesn't run every time
+	@if [ ! -e $(obj)/_libfdt.so ]; then \
+		mv $(obj)/_libfdt*.so $(obj)/_libfdt.so; \
+	fi
+
+$(obj)/_libfdt.so $(obj)/libfdt.py &: rebuild
+	@:
 
-always += _libfdt.so
+always += _libfdt.so libfdt.py
 
 clean-files += libfdt.i _libfdt.so libfdt.py libfdt_wrap.c

scripts/dtc/pylibfdt/libfdt.i_shipped

@@ -7,6 +7,10 @@
 
 %module libfdt
 
+%begin %{
+#define PY_SSIZE_T_CLEAN
+%}
+
 %include <stdint.i>
 
 %{
@@ -18,7 +22,7 @@
  * a struct called fdt_property. That struct causes swig to create a class in
  * libfdt.py called fdt_property(), which confuses things.
  */
-static int fdt_property_stub(void *fdt, const char *name, const char *val,
+static int fdt_property_stub(void *fdt, const char *name, const void *val,
                              int len)
 {
     return fdt_property(fdt, name, val, len);
@@ -92,7 +96,7 @@ def check_err(val, quiet=()):
     Raises
         FdtException if val < 0
     """
-    if val < 0:
+    if isinstance(val, int) and val < 0:
         if -val not in quiet:
             raise FdtException(val)
     return val
@@ -417,7 +421,7 @@ class FdtRo(object):
                                quiet)
         if isinstance(pdata, (int)):
             return pdata
-        return Property(prop_name, bytearray(pdata[0]))
+        return Property(prop_name, bytes(pdata[0]))
 
     def get_phandle(self, nodeoffset):
         """Get the phandle of a node
@@ -431,6 +435,18 @@ class FdtRo(object):
         """
         return fdt_get_phandle(self._fdt, nodeoffset)
 
+    def get_alias(self, name):
+        """Get the full path referenced by a given alias
+
+        Args:
+            name: name of the alias to lookup
+
+        Returns:
+            Full path to the node for the alias named 'name', if it exists
+            None, if the given alias or the /aliases node does not exist
+        """
+        return fdt_get_alias(self._fdt, name)
+
     def parent_offset(self, nodeoffset, quiet=()):
         """Get the offset of a node's parent
 
@@ -624,32 +640,54 @@ class Fdt(FdtRo):
         Raises:
             FdtException if no parent found or other error occurs
         """
-        val = val.encode('utf-8') + '\0'
+        val = val.encode('utf-8') + b'\0'
         return check_err(fdt_setprop(self._fdt, nodeoffset, prop_name,
                                      val, len(val)), quiet)
 
-    def delprop(self, nodeoffset, prop_name):
+    def delprop(self, nodeoffset, prop_name, quiet=()):
         """Delete a property from a node
 
         Args:
             nodeoffset: Node offset containing property to delete
             prop_name: Name of property to delete
+            quiet: Errors to ignore (empty to raise on all errors)
+
+        Returns:
+            Error code, or 0 if OK
 
         Raises:
             FdtError if the property does not exist, or another error occurs
         """
-        return check_err(fdt_delprop(self._fdt, nodeoffset, prop_name))
+        return check_err(fdt_delprop(self._fdt, nodeoffset, prop_name), quiet)
+
+    def add_subnode(self, parentoffset, name, quiet=()):
+        """Add a new subnode to a node
+
+        Args:
+            parentoffset: Parent offset to add the subnode to
+            name: Name of node to add
+
+        Returns:
+            offset of the node created, or negative error code on failure
+
+        Raises:
+            FdtError if there is not enough space, or another error occurs
+        """
+        return check_err(fdt_add_subnode(self._fdt, parentoffset, name), quiet)
 
-    def del_node(self, nodeoffset):
+    def del_node(self, nodeoffset, quiet=()):
         """Delete a node
 
         Args:
-            nodeoffset: Node offset containing property to delete
+            nodeoffset: Offset of node to delete
+
+        Returns:
+            Error code, or 0 if OK
 
         Raises:
-            FdtError if the node does not exist, or another error occurs
+            FdtError if an error occurs
         """
-        return check_err(fdt_del_node(self._fdt, nodeoffset))
+        return check_err(fdt_del_node(self._fdt, nodeoffset), quiet)
 
 
 class Property(bytearray):
@@ -705,8 +743,10 @@ class FdtSw(FdtRo):
 
     # First create the device tree with a node and property:
     sw = FdtSw()
-    with sw.add_node('node'):
-        sw.property_u32('reg', 2)
+    sw.finish_reservemap()
+    with sw.add_node(''):
+        with sw.add_node('node'):
+            sw.property_u32('reg', 2)
     fdt = sw.as_fdt()
 
     # Now we can use it as a real device tree
@@ -996,7 +1036,7 @@ typedef uint32_t fdt32_t;
 			fdt_string(fdt1, fdt32_to_cpu($1->nameoff)));
 		buff = PyByteArray_FromStringAndSize(
 			(const char *)($1 + 1), fdt32_to_cpu($1->len));
-		resultobj = SWIG_Python_AppendOutput(resultobj, buff);
+		resultobj = SWIG_AppendOutput(resultobj, buff);
 	}
 }
 
@@ -1007,17 +1047,24 @@ typedef uint32_t fdt32_t;
 	if (!$1)
 		$result = Py_None;
 	else
-		$result = Py_BuildValue("s#", $1, *arg4);
+        %#if PY_VERSION_HEX >= 0x03000000
+            $result = Py_BuildValue("y#", $1, *arg4);
+        %#else
+            $result = Py_BuildValue("s#", $1, *arg4);
+        %#endif
 }
 
 /* typemap used for fdt_setprop() */
 %typemap(in) (const void *val) {
-    $1 = PyString_AsString($input);   /* char *str */
-}
-
-/* typemap used for fdt_add_reservemap_entry() */
-%typemap(in) uint64_t {
-   $1 = PyLong_AsUnsignedLong($input);
+    %#if PY_VERSION_HEX >= 0x03000000
+        if (!PyBytes_Check($input)) {
+            SWIG_exception_fail(SWIG_TypeError, "bytes expected in method '" "$symname"
+                "', argument " "$argnum"" of type '" "$type""'");
+        }
+        $1 = PyBytes_AsString($input);
+    %#else
+        $1 = PyString_AsString($input);   /* char *str */
+    %#endif
 }
 
 /* typemaps used for fdt_next_node() */
@@ -1028,7 +1075,7 @@ typedef uint32_t fdt32_t;
 
 %typemap(argout) int *depth {
         PyObject *val = Py_BuildValue("i", *arg$argnum);
-        resultobj = SWIG_Python_AppendOutput(resultobj, val);
+        resultobj = SWIG_AppendOutput(resultobj, val);
 }
 
 %apply int *depth { int *depth };
@@ -1039,12 +1086,12 @@ typedef uint32_t fdt32_t;
 }
 
 %typemap(argout) uint64_t * {
-        PyObject *val = PyLong_FromUnsignedLong(*arg$argnum);
+        PyObject *val = PyLong_FromUnsignedLongLong(*arg$argnum);
         if (!result) {
            if (PyTuple_GET_SIZE(resultobj) == 0)
               resultobj = val;
            else
-              resultobj = SWIG_Python_AppendOutput(resultobj, val);
+              resultobj = SWIG_AppendOutput(resultobj, val);
         }
 }
 
@@ -1070,6 +1117,6 @@ int fdt_property_cell(void *fdt, const char *name, uint32_t val);
  * This function has a stub since the name fdt_property is used for both a
   * function and a struct, which confuses SWIG.
  */
-int fdt_property_stub(void *fdt, const char *name, const char *val, int len);
+int fdt_property_stub(void *fdt, const char *name, const void *val, int len);
 
 %include <../libfdt/libfdt.h>