binman: Add a ProcessFdt() method

Some entry types modify the device tree, e.g. to remove microcode or add a
property. So far this just modifies their local copy and does not affect
a 'shared' device tree.

Rather than doing this modification in the ObtainContents() method, and a
new ProcessFdt() method which is specifically designed to modify this
shared device tree.

Move the existing device-tree code over to use this method, reducing
ObtainContents() to the goal of just obtaining the contents without any
processing, even for device tree.

Signed-off-by: Simon Glass <sjg@chromium.org>

tools/binman/README

@@ -462,7 +462,14 @@ Order of image creation
 
 Image creation proceeds in the following order, for each entry in the image.
 
-1. GetEntryContents() - the contents of each entry are obtained, normally by
+1. ProcessFdt() - process the device tree information as required by the
+particular entry. This may involve adding or deleting properties. If the
+processing is complete, this method should return True. If the processing
+cannot complete because it needs the ProcessFdt() method of another entry to
+run first, this method should return False, in which case it will be called
+again later.
+
+2. GetEntryContents() - the contents of each entry are obtained, normally by
 reading from a file. This calls the Entry.ObtainContents() to read the
 contents. The default version of Entry.ObtainContents() calls
 Entry.GetDefaultFilename() and then reads that file. So a common mechanism
@@ -471,35 +478,35 @@ functions must return True when they have read the contents. Binman will
 retry calling the functions a few times if False is returned, allowing
 dependencies between the contents of different entries.
 
-2. GetEntryPositions() - calls Entry.GetPositions() for each entry. This can
+3. GetEntryPositions() - calls Entry.GetPositions() for each entry. This can
 return a dict containing entries that need updating. The key should be the
 entry name and the value is a tuple (pos, size). This allows an entry to
 provide the position and size for other entries. The default implementation
 of GetEntryPositions() returns {}.
 
-3. PackEntries() - calls Entry.Pack() which figures out the position and
+4. PackEntries() - calls Entry.Pack() which figures out the position and
 size of an entry. The 'current' image position is passed in, and the function
 returns the position immediately after the entry being packed. The default
 implementation of Pack() is usually sufficient.
 
-4. CheckSize() - checks that the contents of all the entries fits within
+5. CheckSize() - checks that the contents of all the entries fits within
 the image size. If the image does not have a defined size, the size is set
 large enough to hold all the entries.
 
-5. CheckEntries() - checks that the entries do not overlap, nor extend
+6. CheckEntries() - checks that the entries do not overlap, nor extend
 outside the image.
 
-6. ProcessEntryContents() - this calls Entry.ProcessContents() on each entry.
+7. ProcessEntryContents() - this calls Entry.ProcessContents() on each entry.
 The default implementatoin does nothing. This can be overriden to adjust the
 contents of an entry in some way. For example, it would be possible to create
 an entry containing a hash of the contents of some other entries. At this
 stage the position and size of entries should not be adjusted.
 
-7. WriteSymbols() - write the value of symbols into the U-Boot SPL binary.
+8. WriteSymbols() - write the value of symbols into the U-Boot SPL binary.
 See 'Access to binman entry positions at run time' below for a description of
 what happens in this stage.
 
-8. BuildImage() - builds the image and writes it to a file. This is the final
+9. BuildImage() - builds the image and writes it to a file. This is the final
 step.
 
 

tools/binman/bsection.py

@@ -90,6 +90,21 @@ class Section(object):
             entry.SetPrefix(self._name_prefix)
             self._entries[node.name] = entry
 
+    def ProcessFdt(self, fdt):
+        todo = self._entries.values()
+        for passnum in range(3):
+            next_todo = []
+            for entry in todo:
+                if not entry.ProcessFdt(fdt):
+                    next_todo.append(entry)
+            todo = next_todo
+            if not todo:
+                break
+        if todo:
+            self._Raise('Internal error: Could not complete processing of Fdt: '
+                        'remaining %s' % todo)
+        return True
+
     def CheckSize(self):
         """Check that the section contents does not exceed its size, etc."""
         contents_size = 0

tools/binman/control.py

@@ -21,6 +21,11 @@ import tout
 # Make this global so that it can be referenced from tests
 images = OrderedDict()
 
+# Records the device-tree files known to binman, keyed by filename (e.g.
+# 'u-boot-spl.dtb')
+fdt_files = {}
+
+
 def _ReadImageDesc(binman_node):
     """Read the image descriptions from the /binman node
 
@@ -53,6 +58,24 @@ def _FindBinmanNode(dtb):
             return node
     return None
 
+def GetFdt(fname):
+    """Get the Fdt object for a particular device-tree filename
+
+    Binman keeps track of at least one device-tree file called u-boot.dtb but
+    can also have others (e.g. for SPL). This function looks up the given
+    filename and returns the associated Fdt object.
+
+    Args:
+        fname: Filename to look up (e.g. 'u-boot.dtb').
+
+    Returns:
+        Fdt object associated with the filename
+    """
+    return fdt_files[fname]
+
+def GetFdtPath(fname):
+    return fdt_files[fname]._fname
+
 def Binman(options, args):
     """The main control code for binman
 
@@ -93,12 +116,39 @@ def Binman(options, args):
         try:
             tools.SetInputDirs(options.indir)
             tools.PrepareOutputDir(options.outdir, options.preserve)
-            dtb = fdt.FdtScan(dtb_fname)
+
+            # Get the device tree ready by compiling it and copying the compiled
+            # output into a file in our output directly. Then scan it for use
+            # in binman.
+            dtb_fname = fdt_util.EnsureCompiled(dtb_fname)
+            fname = tools.GetOutputFilename('u-boot-out.dtb')
+            with open(dtb_fname) as infd:
+                with open(fname, 'wb') as outfd:
+                    outfd.write(infd.read())
+            dtb = fdt.FdtScan(fname)
+
+            # Note the file so that GetFdt() can find it
+            fdt_files['u-boot.dtb'] = dtb
             node = _FindBinmanNode(dtb)
             if not node:
                 raise ValueError("Device tree '%s' does not have a 'binman' "
                                  "node" % dtb_fname)
+
             images = _ReadImageDesc(node)
+
+            # Prepare the device tree by making sure that any missing
+            # properties are added (e.g. 'pos' and 'size'). The values of these
+            # may not be correct yet, but we add placeholders so that the
+            # size of the device tree is correct. Later, in
+            # SetCalculatedProperties() we will insert the correct values
+            # without changing the device-tree size, thus ensuring that our
+            # entry positions remain the same.
+            for image in images.values():
+                image.ProcessFdt(dtb)
+
+            dtb.Pack()
+            dtb.Flush()
+
             for image in images.values():
                 # Perform all steps for this image, including checking and
                 # writing it. This means that errors found with a later

tools/binman/entry.py

@@ -130,6 +130,9 @@ class Entry(object):
         self.align_end = fdt_util.GetInt(self._node, 'align-end')
         self.pos_unset = fdt_util.GetBool(self._node, 'pos-unset')
 
+    def ProcessFdt(self, fdt):
+        return True
+
     def SetPrefix(self, prefix):
         """Set the name prefix for a node
 

tools/binman/etype/section.py

@@ -17,6 +17,9 @@ class Entry_section(Entry):
         Entry.__init__(self, image, etype, node)
         self._section = bsection.Section(node.name, node)
 
+    def ProcessFdt(self, fdt):
+        return self._section.ProcessFdt(fdt)
+
     def ObtainContents(self):
         return self._section.GetEntryContents()
 

tools/binman/etype/u_boot_dtb_with_ucode.py

@@ -5,6 +5,7 @@
 # Entry-type module for U-Boot device tree with the microcode removed
 #
 
+import control
 import fdt
 from entry import Entry
 from blob import Entry_blob
@@ -22,13 +23,13 @@ class Entry_u_boot_dtb_with_ucode(Entry_blob):
         self.collate = False
         self.ucode_offset = None
         self.ucode_size = None
+        self.ucode = None
+        self.ready = False
 
     def GetDefaultFilename(self):
         return 'u-boot.dtb'
 
-    def ObtainContents(self):
-        Entry_blob.ObtainContents(self)
-
+    def ProcessFdt(self, fdt):
         # If the section does not need microcode, there is nothing to do
         ucode_dest_entry = self.section.FindEntryType(
             'u-boot-spl-with-ucode-ptr')
@@ -38,36 +39,35 @@ class Entry_u_boot_dtb_with_ucode(Entry_blob):
         if not ucode_dest_entry or not ucode_dest_entry.target_pos:
             return True
 
-        # Create a new file to hold the copied device tree
-        dtb_name = 'u-boot-dtb-with-ucode.dtb'
-        fname = tools.GetOutputFilename(dtb_name)
-        with open(fname, 'wb') as fd:
-            fd.write(self.data)
-
         # Remove the microcode
-        dtb = fdt.FdtScan(fname)
-        ucode = dtb.GetNode('/microcode')
-        if not ucode:
+        fname = self.GetDefaultFilename()
+        fdt = control.GetFdt(fname)
+        self.ucode = fdt.GetNode('/microcode')
+        if not self.ucode:
             raise self.Raise("No /microcode node found in '%s'" % fname)
 
         # There's no need to collate it (move all microcode into one place)
         # if we only have one chunk of microcode.
-        self.collate = len(ucode.subnodes) > 1
-        for node in ucode.subnodes:
+        self.collate = len(self.ucode.subnodes) > 1
+        for node in self.ucode.subnodes:
             data_prop = node.props.get('data')
             if data_prop:
                 self.ucode_data += ''.join(data_prop.bytes)
                 if self.collate:
-                    prop = node.DeleteProp('data')
-                else:
+                    node.DeleteProp('data')
+        return True
+
+    def ObtainContents(self):
+        # Call the base class just in case it does something important.
+        Entry_blob.ObtainContents(self)
+        self._pathname = control.GetFdtPath(self._filename)
+        self.ReadContents()
+        if self.ucode:
+            for node in self.ucode.subnodes:
+                data_prop = node.props.get('data')
+                if data_prop and not self.collate:
                     # Find the offset in the device tree of the ucode data
                     self.ucode_offset = data_prop.GetOffset() + 12
                     self.ucode_size = len(data_prop.bytes)
-        if self.collate:
-            dtb.Pack()
-            dtb.Flush()
-
-            # Make this file the contents of this entry
-            self._pathname = fname
-            self.ReadContents()
+        self.ready = True
         return True

tools/binman/etype/u_boot_ucode.py

@@ -71,7 +71,7 @@ class Entry_u_boot_ucode(Entry_blob):
         fdt_entry = self.section.FindEntryType('u-boot-dtb-with-ucode')
         if not fdt_entry:
             return True
-        if not fdt_entry.ucode_data:
+        if not fdt_entry.ready:
             return False
 
         if not fdt_entry.collate:

tools/binman/etype/u_boot_with_ucode_ptr.py

@@ -28,7 +28,7 @@ class Entry_u_boot_with_ucode_ptr(Entry_blob):
     def GetDefaultFilename(self):
         return 'u-boot-nodtb.bin'
 
-    def ObtainContents(self):
+    def ProcessFdt(self, fdt):
         # Figure out where to put the microcode pointer
         fname = tools.GetInputFilename(self.elf_fname)
         sym = elf.GetSymbolAddress(fname, '_dt_ucode_base_size')
@@ -36,8 +36,7 @@ class Entry_u_boot_with_ucode_ptr(Entry_blob):
            self.target_pos = sym
         elif not fdt_util.GetBool(self._node, 'optional-ucode'):
             self.Raise('Cannot locate _dt_ucode_base_size symbol in u-boot')
-
-        return Entry_blob.ObtainContents(self)
+        return True
 
     def ProcessContents(self):
         # If the image does not need microcode, there is nothing to do
@@ -73,7 +72,7 @@ class Entry_u_boot_with_ucode_ptr(Entry_blob):
             pos, size = ucode_entry.pos, ucode_entry.size
         else:
             dtb_entry = self.section.FindEntryType('u-boot-dtb-with-ucode')
-            if not dtb_entry:
+            if not dtb_entry or not dtb_entry.ready:
                 self.Raise('Cannot find microcode region u-boot-dtb-with-ucode')
             pos = dtb_entry.pos + dtb_entry.ucode_offset
             size = dtb_entry.ucode_size

tools/binman/image.py

@@ -54,6 +54,9 @@ class Image:
             self._filename = filename
         self._section = bsection.Section('main-section', self._node)
 
+    def ProcessFdt(self, fdt):
+        return self._section.ProcessFdt(fdt)
+
     def GetEntryContents(self):
         """Call ObtainContents() for the section
         """