1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * (C) Copyright 2008-2011 4 * Graeme Russ, <graeme.russ@gmail.com> 5 * 6 * (C) Copyright 2002 7 * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se> 8 * 9 * (C) Copyright 2002 10 * Wolfgang Denk, DENX Software Engineering, <wd@denx.de> 11 * 12 * (C) Copyright 2002 13 * Sysgo Real-Time Solutions, GmbH <www.elinos.com> 14 * Marius Groeger <mgroeger@sysgo.de> 15 * 16 * Copyright 2015 ATS Advanced Telematics Systems GmbH 17 * Copyright 2015 Konsulko Group, Matt Porter <mporter@konsulko.com> 18 */ 19 20 #include <common.h> 21 #include <command.h> 22 23 /* 24 * ARMv7M does not support ARM instruction mode. However, the 25 * interworking BLX and BX instructions do encode the ARM/Thumb 26 * field in bit 0. This means that when executing any Branch 27 * and eXchange instruction we must set bit 0 to one to guarantee 28 * that we keep the processor in Thumb instruction mode. From The 29 * ARMv7-M Instruction Set A4.1.1: 30 * "ARMv7-M only supports the Thumb instruction execution state, 31 * therefore the value of address bit [0] must be 1 in interworking 32 * instructions, otherwise a fault occurs." 33 */ 34 unsigned long do_go_exec(ulong (*entry)(int, char * const []), 35 int argc, char * const argv[]) 36 { 37 ulong addr = (ulong)entry | 1; 38 entry = (void *)addr; 39 40 return entry(argc, argv); 41 } 42