diff --git a/usr.bin/dtc/HACKING b/usr.bin/dtc/HACKING index 9447c4f6ebf9..ef858c8885c0 100644 --- a/usr.bin/dtc/HACKING +++ b/usr.bin/dtc/HACKING @@ -1,62 +1,61 @@ - Notes for people hacking on dtc =============================== This file contains some notes for people wishing to hack on dtc. Upstreaming ----------- This code is developed in the git repository: https://github.com/davidchisnall/dtc If you got the source from anywhere else and wish to make changes, please ensure that you are working against the latest version, or you may end up fixing bugs that are already fixed upstream. Although the license makes no requirement that you share any improvements that you make, patches are very welcome. C++11 ----- This project uses C++11, as the goal for FreeBSD 11 is to require C/C++11 as a minimum, either from clang or an external toolchain. In particular, it uses `std::unique_ptr` extensively for memory management within the tree. Unique pointers are also used in several other places to track ownership. Most iterator loops use the new loop syntax and the `auto` type for type deduction. Range-based `for` loops generally improve the readability of the code, though `auto` should only be used in places where the type can be deduced as easily by the reader as by the compiler. The code also makes use of `static_assert()` to track compile-time invariants. Adding New Checks ----------------- Currently, the biggest weakness of this version of the tool is that it lacks most of the semantic checkers that can be implemented by simply reading the ePAPR spec. The `checker` class provides a simple superclass for implementing these quite easily. There are also helper methods on `device_tree` for finding specific nodes, for checks that require some understanding of the structure of the tree. We should probably add a parent pointer to the `node` class for easily walking up the tree. Adding Direct C Output ---------------------- The FreeBSD build system currently uses dtc to generate a blob and then converts this to C source code. A new `output_writer` subclass could easily generate the C directly. Parser Improvements ------------------- There are a few FIXME lines in the parser for some corner cases that are not currently used by FreeBSD. These are mainly related to labels in the middle of values. These can be fixed by creating a new `property_value` with the specified label, starting at the location of the label. Don't forget to remove the associated comments from the BUGS section of the man page if you fix this. diff --git a/usr.bin/dtc/Makefile b/usr.bin/dtc/Makefile index d242ed80e8b1..d7661ae164c3 100644 --- a/usr.bin/dtc/Makefile +++ b/usr.bin/dtc/Makefile @@ -1,14 +1,11 @@ - PROG_CXX=dtc SRCS= dtc.cc input_buffer.cc string.cc dtb.cc fdt.cc checking.cc MAN= dtc.1 WARNS?= 3 CXXFLAGS+= -fno-rtti -fno-exceptions -CXXSTD= c++11 - NO_SHARED?=NO .include diff --git a/usr.bin/dtc/fdt.cc b/usr.bin/dtc/fdt.cc index 5ab9ba10d2f0..f0b98cfe720c 100644 --- a/usr.bin/dtc/fdt.cc +++ b/usr.bin/dtc/fdt.cc @@ -1,2228 +1,2304 @@ /*- * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2013 David Chisnall * All rights reserved. * * This software was developed by SRI International and the University of * Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237) * ("CTSRD"), as part of the DARPA CRASH research programme. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. 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. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. */ #define __STDC_LIMIT_MACROS 1 #include "fdt.hh" #include "dtb.hh" #include #include #include #include #include #include #include #include #include #include #include #include #include #include using std::string; namespace dtc { namespace fdt { uint32_t property_value::get_as_uint32() { if (byte_data.size() != 4) { return 0; } uint32_t v = 0; v &= byte_data[0] << 24; v &= byte_data[1] << 16; v &= byte_data[2] << 8; v &= byte_data[3] << 0; return v; } void property_value::push_to_buffer(byte_buffer &buffer) { if (!byte_data.empty()) { buffer.insert(buffer.end(), byte_data.begin(), byte_data.end()); } else { push_string(buffer, string_data, true); // Trailing nul buffer.push_back(0); } } void property_value::write_dts(FILE *file) { resolve_type(); switch (type) { default: assert(0 && "Invalid type"); case STRING: case STRING_LIST: case CROSS_REFERENCE: write_as_string(file); break; case PHANDLE: write_as_cells(file); break; case BINARY: if (byte_data.size() % 4 == 0) { write_as_cells(file); break; } write_as_bytes(file); break; } } void property_value::resolve_type() { if (type != UNKNOWN) { return; } if (byte_data.empty()) { type = STRING; return; } if (byte_data.back() == 0) { bool is_all_printable = true; int nuls = 0; int bytes = 0; bool lastWasNull = false; for (auto i : byte_data) { bytes++; is_all_printable &= (i == '\0') || isprint(i); if (i == '\0') { // If there are two nulls in a row, then we're probably binary. if (lastWasNull) { type = BINARY; return; } nuls++; lastWasNull = true; } else { lastWasNull = false; } if (!is_all_printable) { break; } } if ((is_all_printable && (bytes > nuls)) || bytes == 0) { type = STRING; if (nuls > 1) { type = STRING_LIST; } return; } } type = BINARY; } size_t property_value::size() { if (!byte_data.empty()) { return byte_data.size(); } return string_data.size() + 1; } void property_value::write_as_string(FILE *file) { putc('"', file); if (byte_data.empty()) { fputs(string_data.c_str(), file); } else { bool hasNull = (byte_data.back() == '\0'); // Remove trailing null bytes from the string before printing as dts. if (hasNull) { byte_data.pop_back(); } for (auto i : byte_data) { // FIXME Escape tabs, newlines, and so on. if (i == '\0') { fputs("\", \"", file); continue; } putc(i, file); } if (hasNull) { byte_data.push_back('\0'); } } putc('"', file); } void property_value::write_as_cells(FILE *file) { putc('<', file); assert((byte_data.size() % 4) == 0); for (auto i=byte_data.begin(), e=byte_data.end(); i!=e ; ++i) { uint32_t v = 0; v = (v << 8) | *i; ++i; v = (v << 8) | *i; ++i; v = (v << 8) | *i; ++i; v = (v << 8) | *i; fprintf(file, "0x%" PRIx32, v); if (i+1 != e) { putc(' ', file); } } putc('>', file); } void property_value::write_as_bytes(FILE *file) { putc('[', file); for (auto i=byte_data.begin(), e=byte_data.end(); i!=e ; i++) { fprintf(file, "%02hhx", *i); if (i+1 != e) { putc(' ', file); } } putc(']', file); } void property::parse_string(text_input_buffer &input) { property_value v; assert(*input == '"'); ++input; std::vector bytes; bool isEscaped = false; while (char c = *input) { if (c == '"' && !isEscaped) { input.consume('"'); break; } isEscaped = (c == '\\'); bytes.push_back(c); ++input; } v.string_data = string(bytes.begin(), bytes.end()); values.push_back(v); } void property::parse_cells(text_input_buffer &input, int cell_size) { assert(*input == '<'); ++input; property_value v; input.next_token(); while (!input.consume('>')) { input.next_token(); // If this is a phandle then we need to get the name of the // referenced node if (input.consume('&')) { if (cell_size != 32) { input.parse_error("reference only permitted in 32-bit arrays"); valid = false; return; } input.next_token(); string referenced; if (!input.consume('{')) { referenced = input.parse_node_name(); } else { referenced = input.parse_to('}'); input.consume('}'); } if (referenced.empty()) { input.parse_error("Expected node name"); valid = false; return; } input.next_token(); // If we already have some bytes, make the phandle a // separate component. if (!v.byte_data.empty()) { values.push_back(v); v = property_value(); } v.string_data = referenced; v.type = property_value::PHANDLE; values.push_back(v); v = property_value(); } else { //FIXME: We should support labels in the middle //of these, but we don't. unsigned long long val; if (!input.consume_integer_expression(val)) { // FIXME: Distinguish invalid syntax from a // number that cannot be represented in an // unsigned long long. input.parse_error("Expected numbers in array of cells"); valid = false; return; } // FIXME: No sign information available, so cannot // distinguish small negative values from large // positive ones, and thus we have to conservatively // permit anything that looks like a sign-extended // negative integer. if (cell_size < 64 && val >= (1ull << cell_size) && (val | ((1ull << (cell_size - 1)) - 1)) != std::numeric_limits::max()) { std::string msg = "Value does not fit in a " + std::to_string(cell_size) + "-bit cell"; input.parse_error(msg.c_str()); valid = false; return; } switch (cell_size) { case 8: v.byte_data.push_back(val); break; case 16: push_big_endian(v.byte_data, (uint16_t)val); break; case 32: push_big_endian(v.byte_data, (uint32_t)val); break; case 64: push_big_endian(v.byte_data, (uint64_t)val); break; default: assert(0 && "Invalid cell size!"); } input.next_token(); } } // Don't store an empty string value here. if (v.byte_data.size() > 0) { values.push_back(v); } } void property::parse_bytes(text_input_buffer &input) { assert(*input == '['); ++input; property_value v; input.next_token(); while (!input.consume(']')) { { //FIXME: We should support //labels in the middle of //these, but we don't. uint8_t val; if (!input.consume_hex_byte(val)) { input.parse_error("Expected hex bytes in array of bytes"); valid = false; return; } v.byte_data.push_back(val); input.next_token(); } } values.push_back(v); } void property::parse_reference(text_input_buffer &input) { assert(*input == '&'); ++input; input.next_token(); property_value v; v.string_data = input.parse_node_name(); if (v.string_data.empty()) { input.parse_error("Expected node name"); valid = false; return; } v.type = property_value::CROSS_REFERENCE; values.push_back(v); } property::property(input_buffer &structs, input_buffer &strings) { uint32_t name_offset; uint32_t length; valid = structs.consume_binary(length) && structs.consume_binary(name_offset); if (!valid) { fprintf(stderr, "Failed to read property\n"); return; } // Find the name input_buffer name_buffer = strings.buffer_from_offset(name_offset); if (name_buffer.finished()) { fprintf(stderr, "Property name offset %" PRIu32 " is past the end of the strings table\n", name_offset); valid = false; return; } key = name_buffer.parse_to(0); // If we're empty, do not push anything as value. if (!length) return; // Read the value uint8_t byte; property_value v; for (uint32_t i=0 ; ifind(name)) == defines->end())) { input.parse_error("Undefined property name\n"); valid = false; return; } values.push_back((*found).second->values[0]); } property::property(text_input_buffer &input, string &&k, string_set &&l, bool semicolonTerminated, define_map *defines) : key(k), labels(l), valid(true) { do { input.next_token(); switch (*input) { case '$': { parse_define(input, defines); if (valid) { break; } } [[fallthrough]]; default: input.parse_error("Invalid property value."); valid = false; return; case '/': { if (input.consume("/incbin/(\"")) { auto loc = input.location(); std::string filename = input.parse_to('"'); if (!(valid = input.consume('"'))) { loc.report_error("Syntax error, expected '\"' to terminate /incbin/("); return; } property_value v; if (!(valid = input.read_binary_file(filename, v.byte_data))) { input.parse_error("Cannot open binary include file"); return; } if (!(valid &= input.consume(')'))) { input.parse_error("Syntax error, expected ')' to terminate /incbin/("); return; } values.push_back(v); break; } unsigned long long bits = 0; valid = input.consume("/bits/"); input.next_token(); valid &= input.consume_integer(bits); if ((bits != 8) && (bits != 16) && (bits != 32) && (bits != 64)) { input.parse_error("Invalid size for elements"); valid = false; } if (!valid) return; input.next_token(); if (*input != '<') { input.parse_error("/bits/ directive is only valid on arrays"); valid = false; return; } parse_cells(input, bits); break; } case '"': parse_string(input); break; case '<': parse_cells(input, 32); break; case '[': parse_bytes(input); break; case '&': parse_reference(input); break; case ';': { break; } } input.next_token(); } while (input.consume(',')); if (semicolonTerminated && !input.consume(';')) { input.parse_error("Expected ; at end of property"); valid = false; } } property_ptr property::parse_dtb(input_buffer &structs, input_buffer &strings) { property_ptr p(new property(structs, strings)); if (!p->valid) { p = nullptr; } return p; } property_ptr property::parse(text_input_buffer &input, string &&key, string_set &&label, bool semicolonTerminated, define_map *defines) { property_ptr p(new property(input, std::move(key), std::move(label), semicolonTerminated, defines)); if (!p->valid) { p = nullptr; } return p; } void property::write(dtb::output_writer &writer, dtb::string_table &strings) { writer.write_token(dtb::FDT_PROP); byte_buffer value_buffer; for (value_iterator i=begin(), e=end() ; i!=e ; ++i) { i->push_to_buffer(value_buffer); } writer.write_data((uint32_t)value_buffer.size()); writer.write_comment(key); writer.write_data(strings.add_string(key)); writer.write_data(value_buffer); } bool property_value::try_to_merge(property_value &other) { resolve_type(); switch (type) { case UNKNOWN: __builtin_unreachable(); assert(0); return false; case EMPTY: *this = other; [[fallthrough]]; case STRING: case STRING_LIST: case CROSS_REFERENCE: return false; case PHANDLE: case BINARY: if (other.type == PHANDLE || other.type == BINARY) { type = BINARY; byte_data.insert(byte_data.end(), other.byte_data.begin(), other.byte_data.end()); return true; } } return false; } void property::write_dts(FILE *file, int indent) { for (int i=0 ; i *vals = &values; std::vector v; // If we've got multiple values then try to merge them all together. if (values.size() > 1) { vals = &v; v.push_back(values.front()); for (auto i=(++begin()), e=end() ; i!=e ; ++i) { if (!v.back().try_to_merge(*i)) { v.push_back(*i); } } } fputs(" = ", file); for (auto i=vals->begin(), e=vals->end() ; i!=e ; ++i) { i->write_dts(file); if (i+1 != e) { putc(',', file); putc(' ', file); } } } fputs(";\n", file); } size_t property::offset_of_value(property_value &val) { size_t off = 0; for (auto &v : values) { if (&v == &val) { return off; } off += v.size(); } return -1; } string node::parse_name(text_input_buffer &input, bool &is_property, const char *error) { if (!valid) { return string(); } input.next_token(); if (is_property) { return input.parse_property_name(); } string n = input.parse_node_or_property_name(is_property); if (n.empty()) { if (n.empty()) { input.parse_error(error); valid = false; } } return n; } node::visit_behavior node::visit(std::function fn, node *parent) { visit_behavior behavior; behavior = fn(*this, parent); if (behavior == VISIT_BREAK) { return VISIT_BREAK; } else if (behavior != VISIT_CONTINUE) { for (auto &&c : children) { behavior = c->visit(fn, this); // Any status other than VISIT_RECURSE stops our execution and // bubbles up to our caller. The caller may then either continue // visiting nodes that are siblings to this one or completely halt // visiting. if (behavior != VISIT_RECURSE) { return behavior; } } } // Continue recursion by default return VISIT_RECURSE; } node::node(input_buffer &structs, input_buffer &strings) : valid(true) { std::vector bytes; while (structs[0] != '\0' && structs[0] != '@') { bytes.push_back(structs[0]); ++structs; } name = string(bytes.begin(), bytes.end()); bytes.clear(); if (structs[0] == '@') { ++structs; while (structs[0] != '\0') { bytes.push_back(structs[0]); ++structs; } unit_address = string(bytes.begin(), bytes.end()); } ++structs; uint32_t token; while (structs.consume_binary(token)) { switch (token) { default: fprintf(stderr, "Unexpected token 0x%" PRIx32 " while parsing node.\n", token); valid = false; return; // Child node, parse it. case dtb::FDT_BEGIN_NODE: { node_ptr child = node::parse_dtb(structs, strings); if (child == 0) { valid = false; return; } children.push_back(std::move(child)); break; } // End of this node, no errors. case dtb::FDT_END_NODE: return; // Property, parse it. case dtb::FDT_PROP: { property_ptr prop = property::parse_dtb(structs, strings); if (prop == 0) { valid = false; return; } props.push_back(prop); break; } break; // End of structs table. Should appear after // the end of the last node. case dtb::FDT_END: fprintf(stderr, "Unexpected FDT_END token while parsing node.\n"); valid = false; return; // NOPs are padding. Ignore them. case dtb::FDT_NOP: break; } } fprintf(stderr, "Failed to read token from structs table while parsing node.\n"); valid = false; return; } node::node(const string &n, const std::vector &p) : name(n) { props.insert(props.begin(), p.begin(), p.end()); } node_ptr node::create_special_node(const string &name, const std::vector &props) { - node_ptr n(new node(name, props)); + // Work around for the fact that we can't call make_shared on something + // with a private constructor. Instead create a subclass with a public + // constructor that is visible only in this function and construct that + // instead. + struct constructable_node : public node + { + constructable_node(const string &n, const std::vector &p) : node(n, p) {} + }; + node_ptr n{std::make_shared(name, props)}; return n; } node::node(text_input_buffer &input, device_tree &tree, string &&n, std::unordered_set &&l, string &&a, define_map *defines) : labels(l), name(n), unit_address(a), valid(true) { if (!input.consume('{')) { input.parse_error("Expected { to start new device tree node.\n"); } input.next_token(); while (valid && !input.consume('}')) { // flag set if we find any characters that are only in // the property name character set, not the node bool is_property = false; // flag set if our node is marked as /omit-if-no-ref/ to be // garbage collected later if nothing references it bool marked_omit_if_no_ref = false; string child_name, child_address; std::unordered_set child_labels; auto parse_delete = [&](const char *expected, bool at) { if (child_name == string()) { input.parse_error(expected); valid = false; return; } input.next_token(); if (at && input.consume('@')) { child_name += '@'; child_name += parse_name(input, is_property, "Expected unit address"); } if (!input.consume(';')) { input.parse_error("Expected semicolon"); valid = false; return; } input.next_token(); }; if (input.consume("/delete-node/")) { input.next_token(); child_name = input.parse_node_name(); parse_delete("Expected node name", true); if (valid) { deleted_children.insert(child_name); } continue; } if (input.consume("/delete-property/")) { input.next_token(); child_name = input.parse_property_name(); parse_delete("Expected property name", false); if (valid) { deleted_props.insert(child_name); } continue; } if (input.consume("/omit-if-no-ref/")) { input.next_token(); marked_omit_if_no_ref = true; tree.set_needs_garbage_collection(); } child_name = parse_name(input, is_property, "Expected property or node name"); while (input.consume(':')) { // Node labels can contain any characters? The // spec doesn't say, so we guess so... is_property = false; child_labels.insert(std::move(child_name)); child_name = parse_name(input, is_property, "Expected property or node name"); } if (input.consume('@')) { child_address = parse_name(input, is_property, "Expected unit address"); } if (!valid) { return; } input.next_token(); // If we're parsing a property, then we must actually do that. if (input.consume('=')) { property_ptr p = property::parse(input, std::move(child_name), std::move(child_labels), true, defines); if (p == 0) { valid = false; } else { props.push_back(p); } } else if (!is_property && *input == ('{')) { node_ptr child = node::parse(input, tree, std::move(child_name), std::move(child_labels), std::move(child_address), defines); if (child) { child->omit_if_no_ref = marked_omit_if_no_ref; children.push_back(std::move(child)); } else { valid = false; } } else if (input.consume(';')) { props.push_back(property_ptr(new property(std::move(child_name), std::move(child_labels)))); } else { input.parse_error("Error parsing property. Expected property value"); valid = false; } input.next_token(); } input.next_token(); input.consume(';'); } bool node::cmp_properties(property_ptr &p1, property_ptr &p2) { return p1->get_key() < p2->get_key(); } bool node::cmp_children(node_ptr &c1, node_ptr &c2) { if (c1->name == c2->name) { return c1->unit_address < c2->unit_address; } return c1->name < c2->name; } void node::sort() { std::sort(property_begin(), property_end(), cmp_properties); std::sort(child_begin(), child_end(), cmp_children); for (auto &c : child_nodes()) { c->sort(); } } node_ptr node::parse(text_input_buffer &input, device_tree &tree, string &&name, string_set &&label, string &&address, define_map *defines) { - node_ptr n(new node(input, - tree, - std::move(name), - std::move(label), - std::move(address), - defines)); + // Work around for the fact that we can't call make_shared on something + // with a private constructor. Instead create a subclass with a public + // constructor that is visible only in this function and construct that + // instead. + struct constructable_node : public node + { + constructable_node(text_input_buffer &input, + device_tree &tree, + std::string &&n, + std::unordered_set &&l, + std::string &&a, + define_map*m) : node(input, + tree, + std::move(n), + std::move(l), + std::move(a), + m) + {} + }; + node_ptr n{std::make_shared(input, + tree, + std::move(name), + std::move(label), + std::move(address), + defines)}; if (!n->valid) { n = 0; } return n; } node_ptr node::parse_dtb(input_buffer &structs, input_buffer &strings) { node_ptr n(new node(structs, strings)); if (!n->valid) { n = 0; } return n; } property_ptr node::get_property(const string &key) { for (auto &i : props) { if (i->get_key() == key) { return i; } } return 0; } void node::merge_node(node_ptr &other) { for (auto &l : other->labels) { labels.insert(l); } children.erase(std::remove_if(children.begin(), children.end(), [&](const node_ptr &p) { string full_name = p->name; if (p->unit_address != string()) { full_name += '@'; full_name += p->unit_address; } if (other->deleted_children.count(full_name) > 0) { other->deleted_children.erase(full_name); return true; } return false; }), children.end()); props.erase(std::remove_if(props.begin(), props.end(), [&](const property_ptr &p) { if (other->deleted_props.count(p->get_key()) > 0) { other->deleted_props.erase(p->get_key()); return true; } return false; }), props.end()); // Note: this is an O(n*m) operation. It might be sensible to // optimise this if we find that there are nodes with very // large numbers of properties, but for typical usage the // entire vector will fit (easily) into cache, so iterating // over it repeatedly isn't that expensive. for (auto &p : other->properties()) { bool found = false; for (auto &mp : properties()) { if (mp->get_key() == p->get_key()) { mp = p; found = true; break; } } if (!found) { add_property(p); } } for (auto &c : other->children) { bool found = false; for (auto &i : children) { if (i->name == c->name && i->unit_address == c->unit_address) { i->merge_node(c); found = true; break; } } if (!found) { children.push_back(std::move(c)); } } } void node::write(dtb::output_writer &writer, dtb::string_table &strings) { writer.write_token(dtb::FDT_BEGIN_NODE); byte_buffer name_buffer; push_string(name_buffer, name); if (unit_address != string()) { name_buffer.push_back('@'); push_string(name_buffer, unit_address); } writer.write_comment(name); writer.write_data(name_buffer); writer.write_data((uint8_t)0); for (auto p : properties()) { p->write(writer, strings); } for (auto &c : child_nodes()) { c->write(writer, strings); } writer.write_token(dtb::FDT_END_NODE); } void node::write_dts(FILE *file, int indent) { for (int i=0 ; iwrite_dts(file, indent+1); } for (auto &c : child_nodes()) { c->write_dts(file, indent+1); } for (int i=0 ; iname, n->unit_address)); for (const string &name : n->labels) { if (name != string()) { auto iter = node_names.find(name); if (iter == node_names.end()) { - node_names.insert(std::make_pair(name, n.get())); + node_names.insert(std::make_pair(name, n)); node_paths.insert(std::make_pair(name, path)); ordered_node_paths.push_back({name, path}); + if (parent) + { + node_name_parents.insert({name, parent}); + } } else { node_names.erase(iter); auto i = node_paths.find(name); if (i != node_paths.end()) { node_paths.erase(name); } fprintf(stderr, "Label not unique: %s. References to this label will not be resolved.\n", name.c_str()); } } } for (auto &c : n->child_nodes()) { - collect_names_recursive(c, path); + collect_names_recursive(n, c, path); } // Now we collect the phandles and properties that reference // other nodes. for (auto &p : n->properties()) { for (auto &v : *p) { if (v.is_phandle()) { fixups.push_back({path, p, v}); } if (v.is_cross_reference()) { cross_references.push_back(&v); } } if ((p->get_key() == "phandle") || (p->get_key() == "linux,phandle")) { if (p->begin()->byte_data.size() != 4) { fprintf(stderr, "Invalid phandle value for node %s. Should be a 4-byte value.\n", n->name.c_str()); valid = false; } else { uint32_t phandle = p->begin()->get_as_uint32(); - used_phandles.insert(std::make_pair(phandle, n.get())); + used_phandles.insert(std::make_pair(phandle, n)); } } } path.pop_back(); } void device_tree::collect_names() { node_path p; node_names.clear(); node_paths.clear(); ordered_node_paths.clear(); cross_references.clear(); fixups.clear(); - collect_names_recursive(root, p); + collect_names_recursive(nullptr, root, p); } property_ptr -device_tree::assign_phandle(node *n, uint32_t &phandle) +device_tree::assign_phandle(node_ptr n, uint32_t &phandle) { // If there is an existing phandle, use it property_ptr p = n->get_property("phandle"); if (p == 0) { p = n->get_property("linux,phandle"); } if (p == 0) { // Otherwise insert a new phandle node property_value v; while (used_phandles.find(phandle) != used_phandles.end()) { // Note that we only don't need to // store this phandle in the set, // because we are monotonically // increasing the value of phandle and // so will only ever revisit this value // if we have used 2^32 phandles, at // which point our blob won't fit in // any 32-bit system and we've done // something badly wrong elsewhere // already. phandle++; } push_big_endian(v.byte_data, phandle++); if (phandle_node_name == BOTH || phandle_node_name == LINUX) { p.reset(new property("linux,phandle")); p->add_value(v); n->add_property(p); } if (phandle_node_name == BOTH || phandle_node_name == EPAPR) { p.reset(new property("phandle")); p->add_value(v); n->add_property(p); } } return (p); } void -device_tree::assign_phandles(node_ptr &n, uint32_t &next) +device_tree::assign_phandles(node_ptr n, uint32_t &next) { if (!n->labels.empty()) { - assign_phandle(n.get(), next); + assign_phandle(n, next); } for (auto &c : n->child_nodes()) { assign_phandles(c, next); } } void device_tree::resolve_cross_references(uint32_t &phandle) { for (auto *pv : cross_references) { node_path path = node_paths[pv->string_data]; auto p = path.begin(); auto pe = path.end(); if (p != pe) { // Skip the first name in the path. It's always "", and implicitly / for (++p ; p!=pe ; ++p) { pv->byte_data.push_back('/'); push_string(pv->byte_data, p->first); if (!(p->second.empty())) { pv->byte_data.push_back('@'); push_string(pv->byte_data, p->second); } } pv->byte_data.push_back(0); } } std::unordered_map phandle_set; for (auto &i : fixups) { phandle_set.insert({&i.val, i}); } std::vector> sorted_phandles; root->visit([&](node &n, node *) { for (auto &p : n.properties()) { for (auto &v : *p) { auto i = phandle_set.find(&v); if (i != phandle_set.end()) { sorted_phandles.push_back(i->second); } } } // Allow recursion return node::VISIT_RECURSE; }, nullptr); assert(sorted_phandles.size() == fixups.size()); for (auto &i : sorted_phandles) { string target_name = i.get().val.string_data; - node *target = nullptr; + node_ptr target; string possible; // If the node name is a path, then look it up by following the path, // otherwise jump directly to the named node. if (target_name[0] == '/') { string path; - target = root.get(); + target = root; std::istringstream ss(target_name); string path_element; // Read the leading / std::getline(ss, path_element, '/'); // Iterate over path elements while (!ss.eof()) { path += '/'; std::getline(ss, path_element, '/'); std::istringstream nss(path_element); string node_name, node_address; std::getline(nss, node_name, '@'); std::getline(nss, node_address, '@'); - node *next = nullptr; + node_ptr next; for (auto &c : target->child_nodes()) { if (c->name == node_name) { if (c->unit_address == node_address) { - next = c.get(); + next = c; break; } else { possible = path + c->name; if (c->unit_address != string()) { possible += '@'; possible += c->unit_address; } } } } path += node_name; if (node_address != string()) { path += '@'; path += node_address; } target = next; if (target == nullptr) { break; } } } else { target = node_names[target_name]; } if (target == nullptr) { if (is_plugin) { unresolved_fixups.push_back(i); continue; } else { fprintf(stderr, "Failed to find node with label: %s\n", target_name.c_str()); if (possible != string()) { fprintf(stderr, "Possible intended match: %s\n", possible.c_str()); } valid = 0; return; } } // If there is an existing phandle, use it property_ptr p = assign_phandle(target, phandle); p->begin()->push_to_buffer(i.get().val.byte_data); assert(i.get().val.byte_data.size() == 4); } } bool device_tree::garbage_collect_marked_nodes() { - std::unordered_set previously_referenced_nodes; - std::unordered_set newly_referenced_nodes; + std::unordered_set previously_referenced_nodes; + std::unordered_set newly_referenced_nodes; auto mark_referenced_nodes_used = [&](node &n) { for (auto &p : n.properties()) { for (auto &v : *p) { if (v.is_phandle()) { - node *nx = node_names[v.string_data]; + node_ptr nx = node_names[v.string_data]; if (nx == nullptr) { // Try it again, but as a path for (auto &s : node_paths) { if (v.string_data == s.second.to_string()) { nx = node_names[s.first]; break; } } } if (nx == nullptr) { // Couldn't resolve this one? continue; } // Only mark those currently unmarked if (!nx->used) { nx->used = 1; newly_referenced_nodes.insert(nx); } } } } }; // Seed our referenced nodes with those that have been seen by a node that // either will not be omitted if it's unreferenced or has a symbol. // Nodes with symbols are explicitly not garbage collected because they may // be expected for referencing by an overlay, and we do not want surprises // there. root->visit([&](node &n, node *) { if (!n.omit_if_no_ref || (write_symbols && !n.labels.empty())) { mark_referenced_nodes_used(n); } // Recurse as normal return node::VISIT_RECURSE; }, nullptr); while (!newly_referenced_nodes.empty()) { - previously_referenced_nodes = std::move(newly_referenced_nodes); - for (auto *n : previously_referenced_nodes) + previously_referenced_nodes = newly_referenced_nodes; + newly_referenced_nodes.clear(); + for (auto &n : previously_referenced_nodes) { mark_referenced_nodes_used(*n); } } previously_referenced_nodes.clear(); bool children_deleted = false; // Delete root->visit([&](node &n, node *) { bool gc_children = false; for (auto &cn : n.child_nodes()) { if (cn->omit_if_no_ref && !cn->used) { gc_children = true; break; } } if (gc_children) { children_deleted = true; n.delete_children_if([](node_ptr &nx) { return (nx->omit_if_no_ref && !nx->used); }); return node::VISIT_CONTINUE; } return node::VISIT_RECURSE; }, nullptr); return children_deleted; } void device_tree::parse_file(text_input_buffer &input, std::vector &roots, bool &read_header) { input.next_token(); // Read the header while (input.consume("/dts-v1/;")) { read_header = true; input.next_token(); } if (input.consume("/plugin/;")) { is_plugin = true; } input.next_token(); if (!read_header) { input.parse_error("Expected /dts-v1/; version string"); } // Read any memory reservations while (input.consume("/memreserve/")) { unsigned long long start, len; input.next_token(); // Read the start and length. if (!(input.consume_integer_expression(start) && (input.next_token(), input.consume_integer_expression(len)))) { input.parse_error("Expected size on /memreserve/ node."); } else { reservations.push_back(reservation(start, len)); } input.next_token(); input.consume(';'); input.next_token(); } while (valid && !input.finished()) { node_ptr n; - if (input.consume('/')) + if (input.consume("/delete-node/")) + { + // Top-level /delete-node/ directives refer to references that must + // be deleted later. + input.next_token(); + auto expect = [&](auto token, const char *msg) + { + if (!input.consume(token)) + { + input.parse_error(msg); + valid = false; + } + input.next_token(); + return valid; + }; + if (expect('&', "Expected reference after top-level /delete-node/.")) + { + string ref = input.parse_node_name(); + if (ref == string()) + { + input.parse_error("Expected label name for top-level /delete-node/."); + valid = false; + } + else + { + deletions.push_back(std::move(ref)); + } + expect(';', "Missing semicolon."); + } + continue; + } + else if (input.consume('/')) { input.next_token(); n = node::parse(input, *this, string(), string_set(), string(), &defines); } else if (input.consume('&')) { input.next_token(); string name; bool name_is_path_reference = false; // This is to deal with names intended as path references, e.g. &{/path}. // While it may make sense in a non-plugin context, we don't support such // usage at this time. if (input.consume('{') && is_plugin) { name = input.parse_to('}'); input.consume('}'); name_is_path_reference = true; } else { name = input.parse_node_name(); } input.next_token(); n = node::parse(input, *this, std::move(name), string_set(), string(), &defines); if (n) { n->name_is_path_reference = name_is_path_reference; } } else { input.parse_error("Failed to find root node /."); } if (n) { roots.push_back(std::move(n)); } else { valid = false; } input.next_token(); } } template void device_tree::write(int fd) { dtb::string_table st; dtb::header head; writer head_writer; writer reservation_writer; writer struct_writer; writer strings_writer; // Build the reservation table reservation_writer.write_comment(string("Memory reservations")); reservation_writer.write_label(string("dt_reserve_map")); for (auto &i : reservations) { reservation_writer.write_comment(string("Reservation start")); reservation_writer.write_data(i.first); reservation_writer.write_comment(string("Reservation length")); reservation_writer.write_data(i.second); } // Write n spare reserve map entries, plus the trailing 0. for (uint32_t i=0 ; i<=spare_reserve_map_entries ; i++) { reservation_writer.write_data((uint64_t)0); reservation_writer.write_data((uint64_t)0); } struct_writer.write_comment(string("Device tree")); struct_writer.write_label(string("dt_struct_start")); root->write(struct_writer, st); struct_writer.write_token(dtb::FDT_END); struct_writer.write_label(string("dt_struct_end")); st.write(strings_writer); // Find the strings size before we stick padding on the end. // Note: We should possibly use a new writer for the padding. head.size_dt_strings = strings_writer.size(); // Stick the padding in the strings writer, but after the // marker indicating that it's the end. // Note: We probably should add a padding call to the writer so // that the asm back end can write padding directives instead // of a load of 0 bytes. for (uint32_t i=0 ; i(fd); } void device_tree::write_asm(int fd) { write(fd); } void device_tree::write_dts(int fd) { FILE *file = fdopen(fd, "w"); fputs("/dts-v1/;\n\n", file); if (!reservations.empty()) { const char msg[] = "/memreserve/"; // Exclude the null byte when we're writing it out to the file. fwrite(msg, sizeof(msg) - 1, 1, file); for (auto &i : reservations) { fprintf(file, " 0x%" PRIx64 " 0x%" PRIx64, i.first, i.second); } fputs(";\n\n", file); } putc('/', file); putc(' ', file); root->write_dts(file, 0); fclose(file); } void device_tree::parse_dtb(const string &fn, FILE *) { auto in = input_buffer::buffer_for_file(fn); if (in == 0) { valid = false; return; } input_buffer &input = *in; dtb::header h; valid = h.read_dtb(input); boot_cpu = h.boot_cpuid_phys; if (h.last_comp_version > 17) { fprintf(stderr, "Don't know how to read this version of the device tree blob"); valid = false; } if (!valid) { return; } input_buffer reservation_map = input.buffer_from_offset(h.off_mem_rsvmap, 0); uint64_t start, length; do { if (!(reservation_map.consume_binary(start) && reservation_map.consume_binary(length))) { fprintf(stderr, "Failed to read memory reservation table\n"); valid = false; return; } if (start != 0 || length != 0) { reservations.push_back(reservation(start, length)); } } while (!((start == 0) && (length == 0))); input_buffer struct_table = input.buffer_from_offset(h.off_dt_struct, h.size_dt_struct); input_buffer strings_table = input.buffer_from_offset(h.off_dt_strings, h.size_dt_strings); uint32_t token; if (!(struct_table.consume_binary(token) && (token == dtb::FDT_BEGIN_NODE))) { fprintf(stderr, "Expected FDT_BEGIN_NODE token.\n"); valid = false; return; } root = node::parse_dtb(struct_table, strings_table); if (!(struct_table.consume_binary(token) && (token == dtb::FDT_END))) { fprintf(stderr, "Expected FDT_END token after parsing root node.\n"); valid = false; return; } valid = (root != 0); } string device_tree::node_path::to_string() const { string path; auto p = begin(); auto pe = end(); if ((p == pe) || (p+1 == pe)) { return string("/"); } // Skip the first name in the path. It's always "", and implicitly / for (++p ; p!=pe ; ++p) { path += '/'; path += p->first; if (!(p->second.empty())) { path += '@'; path += p->second; } } return path; } node_ptr device_tree::create_fragment_wrapper(node_ptr &node, int &fragnum) { // In a plugin, we can massage these non-/ root nodes into into a fragment std::string fragment_address = "fragment@" + std::to_string(fragnum); ++fragnum; std::vector symbols; // Intentionally left empty node_ptr newroot = node::create_special_node("", symbols); node_ptr wrapper = node::create_special_node("__overlay__", symbols); // Generate the fragment with $propname = <&name> property_value v; std::string propname; v.string_data = node->name; if (!node->name_is_path_reference) { propname = "target"; v.type = property_value::PHANDLE; } else { propname = "target-path"; v.type = property_value::STRING; } auto prop = std::make_shared(std::string(propname)); prop->add_value(v); symbols.push_back(prop); node_ptr fragment = node::create_special_node(fragment_address, symbols); wrapper->merge_node(node); fragment->add_child(std::move(wrapper)); newroot->add_child(std::move(fragment)); return newroot; } node_ptr device_tree::generate_root(node_ptr &node, int &fragnum) { string name = node->name; if (name == string()) { return std::move(node); } else if (!is_plugin) { return nullptr; } return create_fragment_wrapper(node, fragnum); } void device_tree::reassign_fragment_numbers(node_ptr &node, int &delta) { for (auto &c : node->child_nodes()) { if (c->name == std::string("fragment")) { int current_address = std::stoi(c->unit_address, nullptr, 16); std::ostringstream new_address; current_address += delta; // It's possible that we hopped more than one somewhere, so just reset // delta to the next in sequence. delta = current_address + 1; new_address << std::hex << current_address; c->unit_address = new_address.str(); } } } void device_tree::parse_dts(const string &fn, FILE *depfile) { auto in = input_buffer::buffer_for_file(fn); if (!in) { valid = false; return; } std::vector roots; std::unordered_set defnames; for (auto &i : defines) { defnames.insert(i.first); } text_input_buffer input(std::move(in), std::move(defnames), std::vector(include_paths), dirname(fn), depfile); bool read_header = false; int fragnum = 0; parse_file(input, roots, read_header); switch (roots.size()) { case 0: valid = false; input.parse_error("Failed to find root node /."); return; case 1: root = generate_root(roots[0], fragnum); if (!root) { valid = false; input.parse_error("Failed to find root node /."); return; } break; default: { root = generate_root(roots[0], fragnum); if (!root) { valid = false; input.parse_error("Failed to find root node /."); return; } for (auto i=++(roots.begin()), e=roots.end() ; i!=e ; ++i) { auto &node = *i; string name = node->name; if (name == string()) { if (is_plugin) { // Re-assign any fragment numbers based on a delta of // fragnum before we merge it reassign_fragment_numbers(node, fragnum); } root->merge_node(node); } else { auto existing = node_names.find(name); if (existing == node_names.end()) { collect_names(); existing = node_names.find(name); } if (existing == node_names.end()) { if (is_plugin) { auto fragment = create_fragment_wrapper(node, fragnum); root->merge_node(fragment); } else { fprintf(stderr, "Unable to merge node: %s\n", name.c_str()); } } else { existing->second->merge_node(node); } } } } } collect_names(); + for (auto &ref : deletions) + { + auto parent = node_name_parents[ref]; + auto node = node_names[ref]; + if (!parent) + { + fprintf(stderr, "Top-level /delete-node/ directive refers to label %s, which is not found.\n", ref.c_str()); + } + else + { + parent->delete_children_if([&](node_ptr &child) { return child == node; }); + } + } // Return value indicates whether we've dirtied the tree or not and need to // recollect names if (garbage_collect && garbage_collect_marked_nodes()) { collect_names(); } uint32_t phandle = 1; // If we're writing symbols, go ahead and assign phandles to the entire // tree. We'll do this before we resolve cross references, just to keep // order semi-predictable and stable. if (write_symbols) { assign_phandles(root, phandle); } resolve_cross_references(phandle); if (write_symbols) { std::vector symbols; // Create a symbol table. Each label in this device tree may be // referenced by other plugins, so we create a __symbols__ node inside // the root that contains mappings (properties) from label names to // paths. for (auto i=ordered_node_paths.rbegin(), e=ordered_node_paths.rend() ; i!=e ; ++i) { auto &s = *i; if (node_paths.find(s.first) == node_paths.end()) { // Erased node, skip it. continue; } property_value v; v.string_data = s.second.to_string(); v.type = property_value::STRING; string name = s.first; auto prop = std::make_shared(std::move(name)); prop->add_value(v); symbols.push_back(prop); } root->add_child(node::create_special_node("__symbols__", symbols)); } // If this is a plugin, then we also need to create two extra nodes. // Internal phandles will need to be renumbered to avoid conflicts with // already-loaded nodes and external references will need to be // resolved. if (is_plugin) { std::vector symbols; // Create the fixups entry. This is of the form: // {target} = {path}:{property name}:{offset} auto create_fixup_entry = [&](fixup &i, string target) { string value = i.path.to_string(); value += ':'; value += i.prop->get_key(); value += ':'; value += std::to_string(i.prop->offset_of_value(i.val)); property_value v; v.string_data = value; v.type = property_value::STRING; auto prop = std::make_shared(std::move(target)); prop->add_value(v); return prop; }; // If we have any unresolved phandle references in this plugin, // then we must update them to 0xdeadbeef and leave a property in // the /__fixups__ node whose key is the label and whose value is // as described above. if (!unresolved_fixups.empty()) { for (auto &i : unresolved_fixups) { auto &val = i.get().val; symbols.push_back(create_fixup_entry(i, val.string_data)); val.byte_data.push_back(0xde); val.byte_data.push_back(0xad); val.byte_data.push_back(0xbe); val.byte_data.push_back(0xef); val.type = property_value::BINARY; } root->add_child(node::create_special_node("__fixups__", symbols)); } symbols.clear(); // If we have any resolved phandle references in this plugin, then // we must create a child in the __local_fixups__ node whose path // matches the node path from the root and whose value contains the // location of the reference within a property. // Create a local_fixups node that is initially empty. node_ptr local_fixups = node::create_special_node("__local_fixups__", symbols); for (auto &i : fixups) { if (!i.val.is_phandle()) { continue; } - node *n = local_fixups.get(); + node_ptr n = local_fixups; for (auto &p : i.path) { // Skip the implicit root if (p.first.empty()) { continue; } bool found = false; for (auto &c : n->child_nodes()) { if (c->name == p.first) { if (c->unit_address == p.second) { - n = c.get(); + n = c; found = true; break; } } } if (!found) { string path = p.first; if (!(p.second.empty())) { path += '@'; path += p.second; } n->add_child(node::create_special_node(path, symbols)); - n = (--n->child_end())->get(); + n = *(--(n->child_end())); } } assert(n); property_value pv; push_big_endian(pv.byte_data, static_cast(i.prop->offset_of_value(i.val))); pv.type = property_value::BINARY; auto key = i.prop->get_key(); property_ptr prop = n->get_property(key); // If we don't have an existing property then create one and // use this property value if (!prop) { prop = std::make_shared(std::move(key)); n->add_property(prop); prop->add_value(pv); } else { // If we do have an existing property value, try to append // this value. property_value &old_val = *(--prop->end()); if (!old_val.try_to_merge(pv)) { prop->add_value(pv); } } } // We've iterated over all fixups, but only emit the // __local_fixups__ if we found some that were resolved internally. if (local_fixups->child_begin() != local_fixups->child_end()) { root->add_child(std::move(local_fixups)); } } } bool device_tree::parse_define(const char *def) { const char *val = strchr(def, '='); if (!val) { if (strlen(def) != 0) { string name(def); defines[name]; return true; } return false; } string name(def, val-def); string name_copy = name; val++; std::unique_ptr raw(new input_buffer(val, strlen(val))); text_input_buffer in(std::move(raw), std::unordered_set(), std::vector(), string(), nullptr); property_ptr p = property::parse(in, std::move(name_copy), string_set(), false); if (p) defines[name] = p; return (bool)p; } } // namespace fdt } // namespace dtc diff --git a/usr.bin/dtc/fdt.hh b/usr.bin/dtc/fdt.hh index 86c9ff153b80..fad9609d40bb 100644 --- a/usr.bin/dtc/fdt.hh +++ b/usr.bin/dtc/fdt.hh @@ -1,1066 +1,1074 @@ /*- * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2013 David Chisnall * All rights reserved. * * This software was developed by SRI International and the University of * Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237) * ("CTSRD"), as part of the DARPA CRASH research programme. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. 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. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. */ #ifndef _FDT_HH_ #define _FDT_HH_ #include #include #include #include #include #include #include "util.hh" #include "input_buffer.hh" namespace dtc { namespace dtb { struct output_writer; class string_table; } namespace fdt { class property; class node; class device_tree; /** * Type for device tree write functions. */ typedef void (device_tree::* tree_write_fn_ptr)(int); /** * Type for device tree read functions. */ typedef void (device_tree::* tree_read_fn_ptr)(const std::string &, FILE *); /** * Type for (owned) pointers to properties. */ typedef std::shared_ptr property_ptr; /** * Owning pointer to a node. */ -typedef std::unique_ptr node_ptr; +typedef std::shared_ptr node_ptr; /** * Map from macros to property pointers. */ typedef std::unordered_map define_map; /** * Set of strings used for label names. */ typedef std::unordered_set string_set; /** * Properties may contain a number of different value, each with a different * label. This class encapsulates a single value. */ struct property_value { /** * The label for this data. This is usually empty. */ std::string label; /** * If this value is a string, or something resolved from a string (a * reference) then this contains the source string. */ std::string string_data; /** * The data that should be written to the final output. */ byte_buffer byte_data; /** * Enumeration describing the possible types of a value. Note that * property-coded arrays will appear simply as binary (or possibly * string, if they happen to be nul-terminated and printable), and must * be checked separately. */ enum value_type { /** * This is a list of strings. When read from source, string * lists become one property value for each string, however * when read from binary we have a single property value * incorporating the entire text, with nul bytes separating the * strings. */ STRING_LIST, /** * This property contains a single string. */ STRING, /** * This is a binary value. Check the size of byte_data to * determine how many bytes this contains. */ BINARY, /** This contains a short-form address that should be replaced * by a fully-qualified version. This will only appear when * the input is a device tree source. When parsed from a * device tree blob, the cross reference will have already been * resolved and the property value will be a string containing * the full path of the target node. */ CROSS_REFERENCE, /** * This is a phandle reference. When parsed from source, the * string_data will contain the node label for the target and, * after cross references have been resolved, the binary data * will contain a 32-bit integer that should match the phandle * property of the target node. */ PHANDLE, /** * An empty property value. This will never appear on a real * property value, it is used by checkers to indicate that no * property values should exist for a property. */ EMPTY, /** * The type of this property has not yet been determined. */ UNKNOWN }; /** * The type of this property. */ value_type type; /** * Returns true if this value is a cross reference, false otherwise. */ inline bool is_cross_reference() { return is_type(CROSS_REFERENCE); } /** * Returns true if this value is a phandle reference, false otherwise. */ inline bool is_phandle() { return is_type(PHANDLE); } /** * Returns true if this value is a string, false otherwise. */ inline bool is_string() { return is_type(STRING); } /** * Returns true if this value is a string list (a nul-separated * sequence of strings), false otherwise. */ inline bool is_string_list() { return is_type(STRING_LIST); } /** * Returns true if this value is binary, false otherwise. */ inline bool is_binary() { return is_type(BINARY); } /** * Returns this property value as a 32-bit integer. Returns 0 if this * property value is not 32 bits long. The bytes in the property value * are assumed to be in big-endian format, but the return value is in * the host native endian. */ uint32_t get_as_uint32(); /** * Default constructor, specifying the label of the value. */ property_value(std::string l=std::string()) : label(l), type(UNKNOWN) {} /** * Writes the data for this value into an output buffer. */ void push_to_buffer(byte_buffer &buffer); /** * Writes the property value to the standard output. This uses the * following heuristics for deciding how to print the output: * * - If the value is nul-terminated and only contains printable * characters, it is written as a string. * - If it is a multiple of 4 bytes long, then it is printed as cells. * - Otherwise, it is printed as a byte buffer. */ void write_dts(FILE *file); /** * Tries to merge adjacent property values, returns true if it succeeds and * false otherwise. */ bool try_to_merge(property_value &other); /** * Returns the size (in bytes) of this property value. */ size_t size(); private: /** * Returns whether the value is of the specified type. If the type of * the value has not yet been determined, then this calculates it. */ inline bool is_type(value_type v) { if (type == UNKNOWN) { resolve_type(); } return type == v; } /** * Determines the type of the value based on its contents. */ void resolve_type(); /** * Writes the property value to the specified file as a quoted string. * This is used when generating DTS. */ void write_as_string(FILE *file); /** * Writes the property value to the specified file as a sequence of * 32-bit big-endian cells. This is used when generating DTS. */ void write_as_cells(FILE *file); /** * Writes the property value to the specified file as a sequence of * bytes. This is used when generating DTS. */ void write_as_bytes(FILE *file); }; /** * A value encapsulating a single property. This contains a key, optionally a * label, and optionally one or more values. */ class property { /** * The name of this property. */ std::string key; /** * Zero or more labels. */ string_set labels; /** * The values in this property. */ std::vector values; /** * Value indicating that this is a valid property. If a parse error * occurs, then this value is false. */ bool valid; /** * Parses a string property value, i.e. a value enclosed in double quotes. */ void parse_string(text_input_buffer &input); /** * Parses one or more 32-bit values enclosed in angle brackets. */ void parse_cells(text_input_buffer &input, int cell_size); /** * Parses an array of bytes, contained within square brackets. */ void parse_bytes(text_input_buffer &input); /** * Parses a reference. This is a node label preceded by an ampersand * symbol, which should expand to the full path to that node. * * Note: The specification says that the target of such a reference is * a node name, however dtc assumes that it is a label, and so we * follow their interpretation for compatibility. */ void parse_reference(text_input_buffer &input); /** * Parse a predefined macro definition for a property. */ void parse_define(text_input_buffer &input, define_map *defines); /** * Constructs a new property from two input buffers, pointing to the * struct and strings tables in the device tree blob, respectively. * The structs input buffer is assumed to have just consumed the * FDT_PROP token. */ property(input_buffer &structs, input_buffer &strings); /** * Parses a new property from the input buffer. */ property(text_input_buffer &input, std::string &&k, string_set &&l, bool terminated, define_map *defines); public: /** * Creates an empty property. */ property(std::string &&k, string_set &&l=string_set()) : key(k), labels(l), valid(true) {} /** * Copy constructor. */ property(property &p) : key(p.key), labels(p.labels), values(p.values), valid(p.valid) {} /** * Factory method for constructing a new property. Attempts to parse a * property from the input, and returns it on success. On any parse * error, this will return 0. */ static property_ptr parse_dtb(input_buffer &structs, input_buffer &strings); /** * Factory method for constructing a new property. Attempts to parse a * property from the input, and returns it on success. On any parse * error, this will return 0. */ static property_ptr parse(text_input_buffer &input, std::string &&key, string_set &&labels=string_set(), bool semicolonTerminated=true, define_map *defines=0); /** * Iterator type used for accessing the values of a property. */ typedef std::vector::iterator value_iterator; /** * Returns an iterator referring to the first value in this property. */ inline value_iterator begin() { return values.begin(); } /** * Returns an iterator referring to the last value in this property. */ inline value_iterator end() { return values.end(); } /** * Adds a new value to an existing property. */ inline void add_value(property_value v) { values.push_back(v); } /** * Returns the key for this property. */ inline const std::string &get_key() { return key; } /** * Writes the property to the specified writer. The property name is a * reference into the strings table. */ void write(dtb::output_writer &writer, dtb::string_table &strings); /** * Writes in DTS format to the specified file, at the given indent * level. This will begin the line with the number of tabs specified * as the indent level and then write the property in the most * applicable way that it can determine. */ void write_dts(FILE *file, int indent); /** * Returns the byte offset of the specified property value. */ size_t offset_of_value(property_value &val); }; /** * Class encapsulating a device tree node. Nodes may contain properties and * other nodes. */ class node { public: /** * The labels for this node, if any. Node labels are used as the * targets for cross references. */ std::unordered_set labels; /** * The name of the node. */ std::string name; /** * The name of the node is a path reference. */ bool name_is_path_reference = false; /** * The unit address of the node, which is optionally written after the * name followed by an at symbol. */ std::string unit_address; /** * A flag indicating that this node has been marked /omit-if-no-ref/ and * will be omitted if it is not referenced, either directly or indirectly, * by a node that is not similarly denoted. */ bool omit_if_no_ref = false; /** * A flag indicating that this node has been referenced, either directly * or indirectly, by a node that is not marked /omit-if-no-ref/. */ bool used = false; /** * The type for the property vector. */ typedef std::vector property_vector; /** * Iterator type for child nodes. */ typedef std::vector::iterator child_iterator; /** * Recursion behavior to be observed for visiting */ enum visit_behavior { /** * Recurse as normal through the rest of the tree. */ VISIT_RECURSE, /** * Continue recursing through the device tree, but do not * recurse through this branch of the tree any further. */ VISIT_CONTINUE, /** * Immediately halt the visit. No further nodes will be visited. */ VISIT_BREAK }; private: /** * Adaptor to use children in range-based for loops. */ struct child_range { child_range(node &nd) : n(nd) {} child_iterator begin() { return n.child_begin(); } child_iterator end() { return n.child_end(); } private: node &n; }; /** * Adaptor to use properties in range-based for loops. */ struct property_range { property_range(node &nd) : n(nd) {} property_vector::iterator begin() { return n.property_begin(); } property_vector::iterator end() { return n.property_end(); } private: node &n; }; /** * The properties contained within this node. */ property_vector props; /** * The children of this node. */ std::vector children; /** * Children that should be deleted from this node when merging. */ std::unordered_set deleted_children; /** * Properties that should be deleted from this node when merging. */ std::unordered_set deleted_props; /** * A flag indicating whether this node is valid. This is set to false * if an error occurs during parsing. */ bool valid; /** * Parses a name inside a node, writing the string passed as the last * argument as an error if it fails. */ std::string parse_name(text_input_buffer &input, bool &is_property, const char *error); /** * Constructs a new node from two input buffers, pointing to the struct * and strings tables in the device tree blob, respectively. */ node(input_buffer &structs, input_buffer &strings); /** * Parses a new node from the specified input buffer. This is called * when the input cursor is on the open brace for the start of the * node. The name, and optionally label and unit address, should have * already been parsed. */ node(text_input_buffer &input, device_tree &tree, std::string &&n, std::unordered_set &&l, std::string &&a, define_map*); /** * Creates a special node with the specified name and properties. */ node(const std::string &n, const std::vector &p); /** * Comparison function for properties, used when sorting the properties * vector. Orders the properties based on their names. */ static inline bool cmp_properties(property_ptr &p1, property_ptr &p2); /* { return p1->get_key() < p2->get_key(); } */ /** * Comparison function for nodes, used when sorting the children * vector. Orders the nodes based on their names or, if the names are * the same, by the unit addresses. */ static inline bool cmp_children(node_ptr &c1, node_ptr &c2); public: /** * Sorts the node's properties and children into alphabetical order and * recursively sorts the children. */ void sort(); /** * Returns an iterator for the first child of this node. */ inline child_iterator child_begin() { return children.begin(); } /** * Returns an iterator after the last child of this node. */ inline child_iterator child_end() { return children.end(); } /** * Returns a range suitable for use in a range-based for loop describing * the children of this node. */ inline child_range child_nodes() { return child_range(*this); } /** * Accessor for the deleted children. */ inline const std::unordered_set &deleted_child_nodes() { return deleted_children; } /** * Accessor for the deleted properties */ inline const std::unordered_set &deleted_properties() { return deleted_props; } /** * Returns a range suitable for use in a range-based for loop describing * the properties of this node. */ inline property_range properties() { return property_range(*this); } /** * Returns an iterator after the last property of this node. */ inline property_vector::iterator property_begin() { return props.begin(); } /** * Returns an iterator for the first property of this node. */ inline property_vector::iterator property_end() { return props.end(); } /** * Factory method for constructing a new node. Attempts to parse a * node in DTS format from the input, and returns it on success. On * any parse error, this will return 0. This should be called with the * cursor on the open brace of the property, after the name and so on * have been parsed. */ static node_ptr parse(text_input_buffer &input, device_tree &tree, std::string &&name, std::unordered_set &&label=std::unordered_set(), std::string &&address=std::string(), define_map *defines=0); /** * Factory method for constructing a new node. Attempts to parse a * node in DTB format from the input, and returns it on success. On * any parse error, this will return 0. This should be called with the * cursor on the open brace of the property, after the name and so on * have been parsed. */ static node_ptr parse_dtb(input_buffer &structs, input_buffer &strings); /** * Construct a new special node from a name and set of properties. */ static node_ptr create_special_node(const std::string &name, const std::vector &props); /** * Returns a property corresponding to the specified key, or 0 if this * node does not contain a property of that name. */ property_ptr get_property(const std::string &key); /** * Adds a new property to this node. */ inline void add_property(property_ptr &p) { props.push_back(p); } /** * Adds a new child to this node. */ inline void add_child(node_ptr &&n) { children.push_back(std::move(n)); } /** * Deletes any children from this node. */ - inline void delete_children_if(bool (*predicate)(node_ptr &)) + inline void delete_children_if(std::function predicate) { children.erase(std::remove_if(children.begin(), children.end(), predicate), children.end()); } /** * Merges a node into this one. Any properties present in both are * overridden, any properties present in only one are preserved. */ void merge_node(node_ptr &other); /** * Write this node to the specified output. Although nodes do not * refer to a string table directly, their properties do. The string * table passed as the second argument is used for the names of * properties within this node and its children. */ void write(dtb::output_writer &writer, dtb::string_table &strings); /** * Writes the current node as DTS to the specified file. The second * parameter is the indent level. This function will start every line * with this number of tabs. */ void write_dts(FILE *file, int indent); /** * Recursively visit this node and then its children based on the * callable's return value. The callable may return VISIT_BREAK * immediately halt all recursion and end the visit, VISIT_CONTINUE to * not recurse into the current node's children, or VISIT_RECURSE to recurse * through children as expected. parent will be passed to the callable. */ visit_behavior visit(std::function, node *parent); }; /** * Class encapsulating the entire parsed FDT. This is the top-level class, * which parses the entire DTS representation and write out the finished * version. */ class device_tree { public: /** * Type used for node paths. A node path is sequence of names and unit * addresses. */ class node_path : public std::vector> { public: /** * Converts this to a string representation. */ std::string to_string() const; }; /** * Name that we should use for phandle nodes. */ enum phandle_format { /** linux,phandle */ LINUX, /** phandle */ EPAPR, /** Create both nodes. */ BOTH }; private: /** * The format that we should use for writing phandles. */ phandle_format phandle_node_name = EPAPR; /** * Flag indicating that this tree is valid. This will be set to false * on parse errors. */ bool valid = true; /** * Flag indicating that this tree requires garbage collection. This will be * set to true if a node marked /omit-if-no-ref/ is encountered. */ bool garbage_collect = false; /** * Type used for memory reservations. A reservation is two 64-bit * values indicating a base address and length in memory that the * kernel should not use. The high 32 bits are ignored on 32-bit * platforms. */ typedef std::pair reservation; /** * The memory reserves table. */ std::vector reservations; /** * Root node. All other nodes are children of this node. */ node_ptr root; /** * Mapping from names to nodes. Only unambiguous names are recorded, * duplicate names are stored as (node*)-1. */ - std::unordered_map node_names; + std::unordered_map node_names; + /** + * Mapping from names to the nodes that contain them. + */ + std::unordered_map node_name_parents; /** * A map from labels to node paths. When resolving cross references, * we look up referenced nodes in this and replace the cross reference * with the full path to its target. */ std::unordered_map node_paths; /** * All of the elements in `node_paths` in the order that they were * created. This is used for emitting the `__symbols__` section, where * we want to guarantee stable ordering. */ std::vector> ordered_node_paths; /** * A collection of property values that are references to other nodes. * These should be expanded to the full path of their targets. */ std::vector cross_references; + /** + * Labels collected from top-level /delete-node/ directives. + */ + std::vector deletions; /** * The location of something requiring a fixup entry. */ struct fixup { /** * The path to the node. */ node_path path; /** * The property containing the reference. */ property_ptr prop; /** * The property value that contains the reference. */ property_value &val; }; /** * A collection of property values that refer to phandles. These will * be replaced by the value of the phandle property in their * destination. */ std::vector fixups; /** * The locations of all of the values that are supposed to become phandle * references, but refer to things outside of this file. */ std::vector> unresolved_fixups; /** * The names of nodes that target phandles. */ std::unordered_set phandle_targets; /** * A collection of input buffers that we are using. These input * buffers are the ones that own their memory, and so we must preserve * them for the lifetime of the device tree. */ std::vector> buffers; /** * A map of used phandle values to nodes. All phandles must be unique, * so we keep a set of ones that the user explicitly provides in the * input to ensure that we don't reuse them. * * This is a map, rather than a set, because we also want to be able to * find phandles that were provided by the user explicitly when we are * doing checking. */ - std::unordered_map used_phandles; + std::unordered_map used_phandles; /** * Paths to search for include files. This contains a set of * nul-terminated strings, which are not owned by this class and so * must be freed separately. */ std::vector include_paths; /** * Dictionary of predefined macros provided on the command line. */ define_map defines; /** * The default boot CPU, specified in the device tree header. */ uint32_t boot_cpu = 0; /** * The number of empty reserve map entries to generate in the blob. */ uint32_t spare_reserve_map_entries = 0; /** * The minimum size in bytes of the blob. */ uint32_t minimum_blob_size = 0; /** * The number of bytes of padding to add to the end of the blob. */ uint32_t blob_padding = 0; /** * Is this tree a plugin? */ bool is_plugin = false; /** * Visit all of the nodes recursively, and if they have labels then add * them to the node_paths and node_names vectors so that they can be * used in resolving cross references. Also collects phandle * properties that have been explicitly added. */ - void collect_names_recursive(node_ptr &n, node_path &path); + void collect_names_recursive(node_ptr parent, node_ptr n, node_path &path); /** * Assign a phandle property to a single node. The next parameter * holds the phandle to be assigned, and will be incremented upon * assignment. */ - property_ptr assign_phandle(node *n, uint32_t &next); + property_ptr assign_phandle(node_ptr n, uint32_t &next); /** * Assign phandle properties to all nodes that have been referenced and * require one. This method will recursively visit the tree starting at * the node that it is passed. */ - void assign_phandles(node_ptr &n, uint32_t &next); + void assign_phandles(node_ptr n, uint32_t &next); /** * Calls the recursive version of this method on every root node. */ void collect_names(); /** * Resolves all cross references. Any properties that refer to another * node must have their values replaced by either the node path or * phandle value. The phandle parameter holds the next phandle to be * assigned, should the need arise. It will be incremented upon each * assignment of a phandle. Garbage collection of unreferenced nodes * marked for "delete if unreferenced" will also occur here. */ void resolve_cross_references(uint32_t &phandle); /** * Garbage collects nodes that have been marked /omit-if-no-ref/ and do not * have any references to them from nodes that are similarly marked. This * is a fairly expensive operation. The return value indicates whether the * tree has been dirtied as a result of this operation, so that the caller * may take appropriate measures to bring the device tree into a consistent * state as needed. */ bool garbage_collect_marked_nodes(); /** * Parses a dts file in the given buffer and adds the roots to the parsed * set. The `read_header` argument indicates whether the header has * already been read. Some dts files place the header in an include, * rather than in the top-level file. */ void parse_file(text_input_buffer &input, std::vector &roots, bool &read_header); /** * Template function that writes a dtb blob using the specified writer. * The writer defines the output format (assembly, blob). */ template void write(int fd); public: /** * Should we write the __symbols__ node (to allow overlays to be linked * against this blob)? */ bool write_symbols = false; /** * Returns the node referenced by the property. If this is a tree that * is in source form, then we have a string that we can use to index * the cross_references array and so we can just look that up. */ - node *referenced_node(property_value &v); + node_ptr referenced_node(property_value &v); /** * Writes this FDT as a DTB to the specified output. */ void write_binary(int fd); /** * Writes this FDT as an assembly representation of the DTB to the * specified output. The result can then be assembled and linked into * a program. */ void write_asm(int fd); /** * Writes the tree in DTS (source) format. */ void write_dts(int fd); /** * Default constructor. Creates a valid, but empty FDT. */ device_tree() {} /** * Constructs a device tree from the specified file name, referring to * a file that contains a device tree blob. */ void parse_dtb(const std::string &fn, FILE *depfile); /** * Construct a fragment wrapper around node. This will assume that node's * name may be used as the target of the fragment, and the contents are to * be wrapped in an __overlay__ node. The fragment wrapper will be assigned * fragnumas its fragment number, and fragment number will be incremented. */ node_ptr create_fragment_wrapper(node_ptr &node, int &fragnum); /** * Generate a root node from the node passed in. This is sensitive to * whether we're in a plugin context or not, so that if we're in a plugin we * can circumvent any errors that might normally arise from a non-/ root. * fragnum will be assigned to any fragment wrapper generated as a result * of the call, and fragnum will be incremented. */ node_ptr generate_root(node_ptr &node, int &fragnum); /** * Reassign any fragment numbers from this new node, based on the given * delta. */ void reassign_fragment_numbers(node_ptr &node, int &delta); /* * Constructs a device tree from the specified file name, referring to * a file that contains device tree source. */ void parse_dts(const std::string &fn, FILE *depfile); /** * Returns whether this tree is valid. */ inline bool is_valid() { return valid; } /** * Mark this tree as needing garbage collection, because an /omit-if-no-ref/ * node has been encountered. */ void set_needs_garbage_collection() { garbage_collect = true; } /** * Sets the format for writing phandle properties. */ inline void set_phandle_format(phandle_format f) { phandle_node_name = f; } /** * Returns a pointer to the root node of this tree. No ownership * transfer. */ inline const node_ptr &get_root() const { return root; } /** * Sets the physical boot CPU. */ void set_boot_cpu(uint32_t cpu) { boot_cpu = cpu; } /** * Sorts the tree. Useful for debugging device trees. */ void sort() { if (root) { root->sort(); } } /** * Adds a path to search for include files. The argument must be a * nul-terminated string representing the path. The device tree keeps * a pointer to this string, but does not own it: the caller is * responsible for freeing it if required. */ void add_include_path(const char *path) { std::string p(path); include_paths.push_back(std::move(p)); } /** * Sets the number of empty reserve map entries to add. */ void set_empty_reserve_map_entries(uint32_t e) { spare_reserve_map_entries = e; } /** * Sets the minimum size, in bytes, of the blob. */ void set_blob_minimum_size(uint32_t s) { minimum_blob_size = s; } /** * Sets the amount of padding to add to the blob. */ void set_blob_padding(uint32_t p) { blob_padding = p; } /** * Parses a predefined macro value. */ bool parse_define(const char *def); }; } // namespace fdt } // namespace dtc #endif // !_FDT_HH_