Add support for locating an image's Fdt map which is used to determine
the contents and structure of the image.
Signed-off-by: Simon Glass <sjg@chromium.org>
At present if this function tries to update the contents such that the
size changes, it raises an error. We plan to add the ability to change
the size of entries after packing is completed, since in some cases it is
not possible to determine the size in advance.
An example of this is with a compressed device tree, where the values
of the device tree change in SetCalculatedProperties() or
ProcessEntryContents(). While the device tree itself does not change size,
since placeholders for any new properties have already bee added by
AddMissingProperties(), we cannot predict the size of the device tree
after compression. If a value changes from 0 to 0x1234 (say), then the
compressed device tree may expand.
As a first step towards supporting this, make ProcessContentsUpdate()
return a value indicating whether the content size is OK. For now this is
always True (since otherwise binman raises an error), but later patches
will adjust this.
Signed-off-by: Simon Glass <sjg@chromium.org>
SetContents() should only be called to set the contents of an entry from
within the ObtainContents() call, since it has no guard against increasing
the size of the contents, thus triggering incorrect operation.
Change all such calls to use ProcessUpdateContents() instead.
Signed-off-by: Simon Glass <sjg@chromium.org>
An FDT map is an entry which holds a full description of the image
entries, in FDT format. It can be discovered using the magic string at
its start. Tools can locate and read this entry to find out what entries
are in the image and where each entry is located.
Signed-off-by: Simon Glass <sjg@chromium.org>
