fdt: test program and run script

issue #188

src/test/fdt/main.cc

@@ -0,0 +1,100 @@
+/**
+ * \brief  Test basic libfdt functionality
+ * \author Sebastian Sumpf
+ * \date   2019-08-09
+ */
+
+/*
+ * Copyright (C) 2019 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU Affero General Public License version 3.
+ */
+
+extern "C" {
+#include <libfdt.h>
+}
+
+#include <base/attached_rom_dataspace.h>
+#include <base/component.h>
+#include <util/endian.h>
+
+using namespace Genode;
+
+enum { MAX_FDT = 128*1024 };
+static char fdt[MAX_FDT];
+
+
+static void memory(int offset)
+{
+	log("Address cells: ", fdt_address_cells(fdt, offset));
+	log("Size cells ", fdt_size_cells(fdt, offset));
+	log("Reg subnode offset: ", fdt_subnode_offset(fdt, offset, "reg"));
+
+	int pr_off;
+	fdt_for_each_property_offset(pr_off, fdt, offset) {
+
+		int len;
+		struct fdt_property const *pr = fdt_get_property_by_offset(fdt, pr_off, &len);
+		log("Property length: ", len);
+		log("name '", fdt_get_string(fdt, host_to_big_endian(pr->nameoff), nullptr), "' ",
+		   " tag: ", Hex(host_to_big_endian(pr->tag)),
+		   " length: ", host_to_big_endian(pr->len),
+		   " name offset: ", Hex(host_to_big_endian(pr->nameoff)));
+
+		if (strcmp(fdt_get_string(fdt, host_to_big_endian(pr->nameoff), nullptr), "reg") != 0) continue;
+		unsigned *data = (unsigned *)pr->data;
+		log("Poperty: ", pr,  " data at ", data);
+		for (int i = 0; i < 4; i++) {
+			log("[", i, "] data: ", Hex(host_to_big_endian(data[i])));
+		}
+
+		log("Set property");
+		data[3] = host_to_big_endian(0xb0000000);
+
+		for (int i = 0; i < 4; i++) {
+			log("[", i, "] data: ", Hex(host_to_big_endian(data[i])));
+		}
+	}
+}
+
+
+void Component::construct(Genode::Env &env)
+{
+	Attached_rom_dataspace dtb { env, "tree.dtb" };
+
+	log("Opened 'tree.dtb'");
+	Genode::memcpy(fdt, dtb.local_addr<void const *>(), dtb.size());
+
+	log("Copied ", dtb.size(), " bytes");
+	log("Tree is ", fdt_check_header(fdt) == 0 ? "valid" : "corrupted");
+
+	int offset = fdt_next_node(fdt, -1, nullptr);
+	int last_offset = offset;
+	while (offset >= 0) {
+		char const *name  = fdt_get_name(fdt, offset, nullptr);
+		log("node: ", name);
+
+		if (strcmp(name, "memory", 6) == 0) {
+			warning("Found memory");
+			memory(offset);
+		}
+
+		if (strcmp(name, "ethernet", 8) == 0) {
+			warning("Deleting ethernet");
+			fdt_del_node(fdt, offset);
+			offset = last_offset;
+		}
+
+		if (strcmp(name, "audio-codec", 11) == 0) {
+			warning("Deleting audio's 'compatible' porpery");
+			fdt_delprop(fdt, offset,"compatible");
+		}
+
+		last_offset = offset;
+		offset = fdt_next_node(fdt, offset, nullptr);
+	}
+
+	fdt_pack(fdt);
+	warning("Total size after pack: ", fdt_totalsize(fdt), " bytes");
+}

src/test/fdt/target.mk

@@ -0,0 +1,5 @@
+SRC_CC   = main.cc
+TARGET   = test-fdt
+LIBS     = base fdt
+
+CC_CXX_WARN_STRICT =