different name for each and specifying the type with the 'type' attribute.
+Sections and hiearchical images
+-------------------------------
+
+Sometimes it is convenient to split an image into several pieces, each of which
+contains its own set of binaries. An example is a flash device where part of
+the image is read-only and part is read-write. We can set up sections for each
+of these, and place binaries in them independently. The image is still produced
+as a single output file.
+
+This feature provides a way of creating hierarchical images. For example here
+is an example with two copies of U-Boot. One is read-only (ro), intended to be
+written only in the factory. Another is read-write (rw), so that it can be
+upgraded in the field. The sizes are fixed so that the ro/rw boundary is known
+and can be programmed:
+
+ binman {
+ section@0 {
+ read-only;
+ size = <0x100000>;
+ u-boot {
+ };
+ };
+ section@1 {
+ size = <0x100000>;
+ u-boot {
+ };
+ };
+ };
+
+This image could be placed into a SPI flash chip, with the protection boundary
+set at 1MB.
+
+A few special properties are provided for sections:
+
+read-only:
+ Indicates that this section is read-only. This has no impact on binman's
+ operation, but his property can be read at run time.
+
+
Special properties
------------------
- Allow easy building of images by specifying just the board name
- Produce a full Python binding for libfdt (for upstream)
- Add an option to decode an image into the constituent binaries
-- Suppoort hierarchical images (packing of binaries into another binary
- which is then placed in the image)
- Support building an image for a board (-b) more completely, with a
configurable build directory
- Consider making binman work with buildman, although if it is used in the
pos = 0
prev_name = 'None'
for entry in self._entries.values():
+ entry.CheckPosition()
if (entry.pos < self._skip_at_start or
entry.pos >= self._skip_at_start + self._size):
entry.Raise("Position %#x (%d) is outside the section starting "
section: Section containing the entry
"""
pass
+
+ def CheckPosition(self):
+ """Check that the entry positions are correct
+
+ This is used for entries which have extra position requirements (other
+ than having to be fully inside their section). Sub-classes can implement
+ this function and raise if there is a problem.
+ """
+ pass
--- /dev/null
+# SPDX-License-Identifier: GPL-2.0+
+# Copyright (c) 2018 Google, Inc
+# Written by Simon Glass <sjg@chromium.org>
+#
+# Entry-type module for sections, which are entries which can contain other
+# entries.
+#
+
+from entry import Entry
+import fdt_util
+import tools
+
+import bsection
+
+class Entry_section(Entry):
+ def __init__(self, image, etype, node):
+ Entry.__init__(self, image, etype, node)
+ self._section = bsection.Section(node.name, node)
+
+ def ObtainContents(self):
+ self._section.GetEntryContents()
+
+ def GetData(self):
+ return self._section.GetData()
+
+ def GetPositions(self):
+ """Handle entries that want to set the position/size of other entries
+
+ This calls each entry's GetPositions() method. If it returns a list
+ of entries to update, it updates them.
+ """
+ self._section.GetEntryPositions()
+ return {}
+
+ def Pack(self, pos):
+ """Pack all entries into the section"""
+ self._section.PackEntries()
+ self.size = self._section.CheckSize()
+ return super(Entry_section, self).Pack(pos)
+
+ def WriteSymbols(self, section):
+ """Write symbol values into binary files for access at run time"""
+ self._section.WriteSymbols()
+
+ def ProcessContents(self):
+ self._section.ProcessEntryContents()
+ super(Entry_section, self).ProcessContents()
+
+ def CheckPosition(self):
+ self._section.CheckEntries()
data = self._DoReadFile('54_unit_address.dts')
self.assertEqual(U_BOOT_DATA + U_BOOT_DATA, data)
+ def testSections(self):
+ """Basic test of sections"""
+ data = self._DoReadFile('55_sections.dts')
+ expected = U_BOOT_DATA + '!' * 12 + U_BOOT_DATA + 'a' * 12 + '&' * 8
+ self.assertEqual(expected, data)
if __name__ == "__main__":
unittest.main()
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+
+/dts-v1/;
+
+/ {
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ binman {
+ pad-byte = <0x26>;
+ size = <0x28>;
+ section@0 {
+ read-only;
+ size = <0x10>;
+ pad-byte = <0x21>;
+
+ u-boot {
+ };
+ };
+ section@1 {
+ size = <0x10>;
+ pad-byte = <0x61>;
+
+ u-boot {
+ };
+ };
+ };
+};
projects / u-boot.git / commitdiff
