From f7107fb7954b45547ab792493e86760cf6fe33ed Mon Sep 17 00:00:00 2001 From: Anthony Gutierrez Date: Fri, 15 Feb 2013 18:48:59 -0500 Subject: loader: add a flattened device tree blob (dtb) object this adds a dtb_object so the loader can load in the dtb file for linux/android ARM kernels. --- src/base/loader/dtb_object.cc | 169 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 169 insertions(+) create mode 100644 src/base/loader/dtb_object.cc (limited to 'src/base/loader/dtb_object.cc') diff --git a/src/base/loader/dtb_object.cc b/src/base/loader/dtb_object.cc new file mode 100644 index 000000000..f22cee1ed --- /dev/null +++ b/src/base/loader/dtb_object.cc @@ -0,0 +1,169 @@ +/* + * Copyright (c) 2013 The Regents of The University of Michigan + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Anthony Gutierrez + */ + +#include +#include +#include + +#include + +#include "base/loader/dtb_object.hh" +#include "fdt.h" +#include "libfdt.h" + +ObjectFile * +DtbObject::tryFile(const std::string &fname, int fd, size_t len, uint8_t *data) +{ + // Check if this is a FDT file by looking for magic number + if (fdt_magic((void*)data) == FDT_MAGIC) { + return new DtbObject(fname, fd, len, data, + ObjectFile::UnknownArch, ObjectFile::UnknownOpSys); + } else { + return NULL; + } +} + +DtbObject::DtbObject(const std::string &_filename, int _fd, + size_t _len, uint8_t *_data, + Arch _arch, OpSys _opSys) + : ObjectFile(_filename, _fd, _len, _data, _arch, _opSys) +{ + text.baseAddr = 0; + text.size = len; + text.fileImage = fileData; + + data.baseAddr = 0; + data.size = 0; + data.fileImage = NULL; + + bss.baseAddr = 0; + bss.size = 0; + bss.fileImage = NULL; + + fileDataMmapped = true; +} + +DtbObject::~DtbObject() +{ + if (descriptor >= 0) { + ::close(descriptor); + descriptor = -1; + } + + // Make sure to clean up memory properly depending + // on how buffer was allocated. + if (fileData && !fileDataMmapped) { + delete [] fileData; + fileData = NULL; + } else if (fileData) { + munmap(fileData, len); + fileData = NULL; + } +} + +bool +DtbObject::addBootCmdLine(const char* _args, size_t len) +{ + const char* root_path = "/"; + const char* node_name = "chosen"; + const char* full_path_node_name = "/chosen"; + const char* property_name = "bootargs"; + + // Make a new buffer that has extra space to add nodes/properties + int newLen = 2*this->len; + uint8_t* fdt_buf_w_space = new uint8_t[newLen]; + // Copy and unpack flattened device tree into new buffer + int ret = fdt_open_into((void*)fileData, (void*)fdt_buf_w_space, (newLen)); + if (ret < 0) { + warn("Error resizing buffer of flattened device tree, " + "errno: %d\n", ret); + delete [] fdt_buf_w_space; + return false; + } + + // First try finding the /chosen node in the dtb + int offset = fdt_path_offset((void*)fdt_buf_w_space, full_path_node_name); + if (offset < 0) { + // try adding the node by walking dtb tree to proper insertion point + offset = fdt_path_offset((void*)fdt_buf_w_space, root_path); + offset = fdt_add_subnode((void*)fdt_buf_w_space, offset, node_name); + offset = fdt_path_offset((void*)fdt_buf_w_space, full_path_node_name); + if (offset < 0) { + warn("Error finding or adding \"chosen\" subnode to flattened " + "device tree, errno: %d\n", offset); + delete [] fdt_buf_w_space; + return false; + } + } + + // Set the bootargs property in the /chosen node + ret = fdt_setprop((void*)fdt_buf_w_space, offset, property_name, + (const void*)_args, len+1); + if (ret < 0) { + warn("Error setting \"bootargs\" property to flattened device tree, " + "errno: %d\n", ret); + delete [] fdt_buf_w_space; + return false; + } + + // Repack the dtb for kernel use + ret = fdt_pack((void*)fdt_buf_w_space); + if (ret < 0) { + warn("Error re-packing flattened device tree structure, " + "errno: %d\n", ret); + delete [] fdt_buf_w_space; + return false; + } + + text.size = newLen; + text.fileImage = fdt_buf_w_space; + + // clean up old buffer and set to new fdt blob + munmap(fileData, this->len); + fileData = fdt_buf_w_space; + fileDataMmapped = false; + this->len = newLen; + + return true; +} + +bool +DtbObject::loadGlobalSymbols(SymbolTable *symtab, Addr addrMask) +{ + // nothing to do here + return false; +} + +bool +DtbObject::loadLocalSymbols(SymbolTable *symtab, Addr addrMask) +{ + // nothing to do here + return false; +} -- cgit v1.2.3