# SPDX-License-Identifier: GPL-2.0+ # Copyright 2019 Google LLC # Written by Simon Glass # # Entry-type module for a Coreboot Filesystem (CBFS) # from collections import OrderedDict from binman import cbfs_util from binman.cbfs_util import CbfsWriter from binman.entry import Entry from dtoc import fdt_util class Entry_cbfs(Entry): """Coreboot Filesystem (CBFS) A CBFS provides a way to group files into a group. It has a simple directory structure and allows the position of individual files to be set, since it is designed to support execute-in-place in an x86 SPI-flash device. Where XIP is not used, it supports compression and storing ELF files. CBFS is used by coreboot as its way of orgnanising SPI-flash contents. The contents of the CBFS are defined by subnodes of the cbfs entry, e.g.:: cbfs { size = <0x100000>; u-boot { cbfs-type = "raw"; }; u-boot-dtb { cbfs-type = "raw"; }; }; This creates a CBFS 1MB in size two files in it: u-boot.bin and u-boot.dtb. Note that the size is required since binman does not support calculating it. The contents of each entry is just what binman would normally provide if it were not a CBFS node. A blob type can be used to import arbitrary files as with the second subnode below:: cbfs { size = <0x100000>; u-boot { cbfs-name = "BOOT"; cbfs-type = "raw"; }; dtb { type = "blob"; filename = "u-boot.dtb"; cbfs-type = "raw"; cbfs-compress = "lz4"; cbfs-offset = <0x100000>; }; }; This creates a CBFS 1MB in size with u-boot.bin (named "BOOT") and u-boot.dtb (named "dtb") and compressed with the lz4 algorithm. Properties supported in the top-level CBFS node: cbfs-arch: Defaults to "x86", but you can specify the architecture if needed. Properties supported in the CBFS entry subnodes: cbfs-name: This is the name of the file created in CBFS. It defaults to the entry name (which is the node name), but you can override it with this property. cbfs-type: This is the CBFS file type. The following are supported: raw: This is a 'raw' file, although compression is supported. It can be used to store any file in CBFS. stage: This is an ELF file that has been loaded (i.e. mapped to memory), so appears in the CBFS as a flat binary. The input file must be an ELF image, for example this puts "u-boot" (the ELF image) into a 'stage' entry:: cbfs { size = <0x100000>; u-boot-elf { cbfs-name = "BOOT"; cbfs-type = "stage"; }; }; You can use your own ELF file with something like:: cbfs { size = <0x100000>; something { type = "blob"; filename = "cbfs-stage.elf"; cbfs-type = "stage"; }; }; As mentioned, the file is converted to a flat binary, so it is equivalent to adding "u-boot.bin", for example, but with the load and start addresses specified by the ELF. At present there is no option to add a flat binary with a load/start address, similar to the 'add-flat-binary' option in cbfstool. cbfs-offset: This is the offset of the file's data within the CBFS. It is used to specify where the file should be placed in cases where a fixed position is needed. Typical uses are for code which is not relocatable and must execute in-place from a particular address. This works because SPI flash is generally mapped into memory on x86 devices. The file header is placed before this offset so that the data start lines up exactly with the chosen offset. If this property is not provided, then the file is placed in the next available spot. The current implementation supports only a subset of CBFS features. It does not support other file types (e.g. payload), adding multiple files (like the 'files' entry with a pattern supported by binman), putting files at a particular offset in the CBFS and a few other things. Of course binman can create images containing multiple CBFSs, simply by defining these in the binman config:: binman { size = <0x800000>; cbfs { offset = <0x100000>; size = <0x100000>; u-boot { cbfs-type = "raw"; }; u-boot-dtb { cbfs-type = "raw"; }; }; cbfs2 { offset = <0x700000>; size = <0x100000>; u-boot { cbfs-type = "raw"; }; u-boot-dtb { cbfs-type = "raw"; }; image { type = "blob"; filename = "image.jpg"; }; }; }; This creates an 8MB image with two CBFSs, one at offset 1MB, one at 7MB, both of size 1MB. """ def __init__(self, section, etype, node): # Put this here to allow entry-docs and help to work without libfdt global state from binman import state super().__init__(section, etype, node) self._cbfs_arg = fdt_util.GetString(node, 'cbfs-arch', 'x86') self.align_default = None self._cbfs_entries = OrderedDict() self._ReadSubnodes() self.reader = None def ObtainContents(self, skip=None): arch = cbfs_util.find_arch(self._cbfs_arg) if arch is None: self.Raise("Invalid architecture '%s'" % self._cbfs_arg) if self.size is None: self.Raise("'cbfs' entry must have a size property") cbfs = CbfsWriter(self.size, arch) for entry in self._cbfs_entries.values(): # First get the input data and put it in a file. If not available, # try later. if entry != skip and not entry.ObtainContents(): return False data = entry.GetData() cfile = None if entry._type == 'raw': cfile = cbfs.add_file_raw(entry._cbfs_name, data, entry._cbfs_offset, entry._cbfs_compress) elif entry._type == 'stage': cfile = cbfs.add_file_stage(entry._cbfs_name, data, entry._cbfs_offset) else: entry.Raise("Unknown cbfs-type '%s' (use 'raw', 'stage')" % entry._type) if cfile: entry._cbfs_file = cfile data = cbfs.get_data() self.SetContents(data) return True def _ReadSubnodes(self): """Read the subnodes to find out what should go in this CBFS""" for node in self._node.subnodes: entry = Entry.Create(self, node) entry.ReadNode() entry._cbfs_name = fdt_util.GetString(node, 'cbfs-name', entry.name) entry._type = fdt_util.GetString(node, 'cbfs-type') compress = fdt_util.GetString(node, 'cbfs-compress', 'none') entry._cbfs_offset = fdt_util.GetInt(node, 'cbfs-offset') entry._cbfs_compress = cbfs_util.find_compress(compress) if entry._cbfs_compress is None: self.Raise("Invalid compression in '%s': '%s'" % (node.name, compress)) self._cbfs_entries[entry._cbfs_name] = entry def SetImagePos(self, image_pos): """Override this function to set all the entry properties from CBFS We can only do this once image_pos is known Args: image_pos: Position of this entry in the image """ super().SetImagePos(image_pos) # Now update the entries with info from the CBFS entries for entry in self._cbfs_entries.values(): cfile = entry._cbfs_file entry.size = cfile.data_len entry.offset = cfile.calced_cbfs_offset entry.image_pos = self.image_pos + entry.offset if entry._cbfs_compress: entry.uncomp_size = cfile.memlen def AddMissingProperties(self, have_image_pos): super().AddMissingProperties(have_image_pos) for entry in self._cbfs_entries.values(): entry.AddMissingProperties(have_image_pos) if entry._cbfs_compress: state.AddZeroProp(entry._node, 'uncomp-size') # Store the 'compress' property, since we don't look at # 'cbfs-compress' in Entry.ReadData() state.AddString(entry._node, 'compress', cbfs_util.compress_name(entry._cbfs_compress)) def SetCalculatedProperties(self): """Set the value of device-tree properties calculated by binman""" super().SetCalculatedProperties() for entry in self._cbfs_entries.values(): state.SetInt(entry._node, 'offset', entry.offset) state.SetInt(entry._node, 'size', entry.size) state.SetInt(entry._node, 'image-pos', entry.image_pos) if entry.uncomp_size is not None: state.SetInt(entry._node, 'uncomp-size', entry.uncomp_size) def ListEntries(self, entries, indent): """Override this method to list all files in the section""" super().ListEntries(entries, indent) for entry in self._cbfs_entries.values(): entry.ListEntries(entries, indent + 1) def GetEntries(self): return self._cbfs_entries def ReadData(self, decomp=True): data = super().ReadData(True) return data def ReadChildData(self, child, decomp=True): if not self.reader: data = super().ReadData(True) self.reader = cbfs_util.CbfsReader(data) reader = self.reader cfile = reader.files.get(child.name) return cfile.data if decomp else cfile.orig_data def WriteChildData(self, child): self.ObtainContents(skip=child) return True