After any node/property deletion the device tree can be packed to remove spare space. Add a way to perform this operation.
Note that for fdt_fallback, fdtput automatically packs the device tree after deletion, so no action is required here.
Signed-off-by: Simon Glass sjg@chromium.org ---
lib/libfdt/libfdt.swig | 1 + tools/dtoc/fdt.py | 16 ++++++++++++++++ tools/dtoc/fdt_normal.py | 11 +++++++++++ 3 files changed, 28 insertions(+)
diff --git a/lib/libfdt/libfdt.swig b/lib/libfdt/libfdt.swig index ce516fd..0cb7977 100644 --- a/lib/libfdt/libfdt.swig +++ b/lib/libfdt/libfdt.swig @@ -107,3 +107,4 @@ int fdt_next_subnode(const void *fdt, int offset); int fdt_delprop(void *fdt, int nodeoffset, const char *name);
const char *fdt_strerror(int errval); +int fdt_pack(void *fdt); diff --git a/tools/dtoc/fdt.py b/tools/dtoc/fdt.py index f01c7b1..403eb1f 100644 --- a/tools/dtoc/fdt.py +++ b/tools/dtoc/fdt.py @@ -240,3 +240,19 @@ class Fdt: return None return node
+ def Flush(self): + """Flush device tree changes back to the file + + If the device tree has changed in memory, write it back to the file. + Subclasses can implement this if needed. + """ + pass + + def Pack(self): + """Pack the device tree down to its minimum size + + When nodes and properties shrink or are deleted, wasted space can + build up in the device tree binary. Subclasses can implement this + to remove that spare space. + """ + pass diff --git a/tools/dtoc/fdt_normal.py b/tools/dtoc/fdt_normal.py index 52d8055..f2cf608 100644 --- a/tools/dtoc/fdt_normal.py +++ b/tools/dtoc/fdt_normal.py @@ -140,6 +140,17 @@ class FdtNormal(Fdt): """ return self._fdt
+ def Flush(self): + """Flush device tree changes back to the file""" + with open(self._fname, 'wb') as fd: + fd.write(self._fdt) + + def Pack(self): + """Pack the device tree down to its minimum size""" + CheckErr(libfdt.fdt_pack(self._fdt), 'pack') + fdt_len = libfdt.fdt_totalsize(self._fdt) + del self._fdt[fdt_len:] + def GetProps(self, node, path): """Get all properties from a node.