From patchwork Thu Dec 8 17:35:06 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Martin X-Patchwork-Id: 5542 Return-Path: X-Original-To: patchwork@peony.canonical.com Delivered-To: patchwork@peony.canonical.com Received: from fiordland.canonical.com (fiordland.canonical.com [91.189.94.145]) by peony.canonical.com (Postfix) with ESMTP id 12F3823E0C for ; Thu, 8 Dec 2011 17:35:21 +0000 (UTC) Received: from mail-bw0-f52.google.com (mail-bw0-f52.google.com [209.85.214.52]) by fiordland.canonical.com (Postfix) with ESMTP id EDA6CA1829B for ; Thu, 8 Dec 2011 17:35:20 +0000 (UTC) Received: by bke17 with SMTP id 17so2624196bke.11 for ; Thu, 08 Dec 2011 09:35:20 -0800 (PST) Received: by 10.204.156.208 with SMTP id y16mr1936420bkw.72.1323365720627; Thu, 08 Dec 2011 09:35:20 -0800 (PST) X-Forwarded-To: linaro-patchwork@canonical.com X-Forwarded-For: patch@linaro.org linaro-patchwork@canonical.com Delivered-To: patches@linaro.org Received: by 10.205.129.2 with SMTP id hg2cs97855bkc; Thu, 8 Dec 2011 09:35:20 -0800 (PST) Received: by 10.213.34.72 with SMTP id k8mr498851ebd.108.1323365719034; Thu, 08 Dec 2011 09:35:19 -0800 (PST) Received: from mail-ee0-f50.google.com (mail-ee0-f50.google.com [74.125.83.50]) by mx.google.com with ESMTPS id a48si2769035eec.155.2011.12.08.09.35.18 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 08 Dec 2011 09:35:18 -0800 (PST) Received-SPF: neutral (google.com: 74.125.83.50 is neither permitted nor denied by best guess record for domain of dave.martin@linaro.org) client-ip=74.125.83.50; Authentication-Results: mx.google.com; spf=neutral (google.com: 74.125.83.50 is neither permitted nor denied by best guess record for domain of dave.martin@linaro.org) smtp.mail=dave.martin@linaro.org Received: by eeke53 with SMTP id e53so1383909eek.37 for ; Thu, 08 Dec 2011 09:35:18 -0800 (PST) Received: by 10.180.88.106 with SMTP id bf10mr6952983wib.25.1323365718569; Thu, 08 Dec 2011 09:35:18 -0800 (PST) Received: from e103592.peterhouse.linaro.org (fw-lnat.cambridge.arm.com. [217.140.96.63]) by mx.google.com with ESMTPS id n9sm9423737wbo.16.2011.12.08.09.35.16 (version=SSLv3 cipher=OTHER); Thu, 08 Dec 2011 09:35:17 -0800 (PST) From: Dave Martin To: linux-arm-kernel@lists.infradead.org Cc: patches@linaro.org, Bi Junxiao , Rabin Vincent , Tixy , Leif Lindholm , Nicolas Pitre Subject: [PATCH v3] ARM: Add generic instruction opcode manipulation helpers Date: Thu, 8 Dec 2011 17:35:06 +0000 Message-Id: <1323365706-3047-1-git-send-email-dave.martin@linaro.org> X-Mailer: git-send-email 1.7.4.1 This patch adds some endianness-agnostic helpers to convert machine instructions between canonical integer form and in-memory representation. A canonical integer form for representing instructions is also formalised here. Signed-off-by: Dave Martin Acked-by: Nicolas Pitre --- Changes since v1: v2: Remove unnecessary typedef for arm_opcode_t. The general "everything is a word" concept works just fine here -- we don't need a typedef, and people will probably not use it anyway. v3: Fix some stupid errors: * remove bogus extra (x) in __opcode_to_mem_arm * fix use of nonexistent "thumb_opcode" argument in __opcode_thumb32_{first,second} which causes these macros to be broken. arch/arm/include/asm/opcodes.h | 68 ++++++++++++++++++++++++++++++++++++++++ 1 files changed, 68 insertions(+), 0 deletions(-) create mode 100644 arch/arm/include/asm/opcodes.h diff --git a/arch/arm/include/asm/opcodes.h b/arch/arm/include/asm/opcodes.h new file mode 100644 index 0000000..eed11db --- /dev/null +++ b/arch/arm/include/asm/opcodes.h @@ -0,0 +1,68 @@ +/* + * arch/arm/include/asm/opcodes.h + * + * Copyright (C) 2011 Linaro Limited + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#ifndef __ARM_OPCODES_H +#define __ARM_OPCODES_H + +#include +#include + +/* + * Canonical instruction representation: + * + * ARM: 0xKKLLMMNN + * Thumb 16-bit: 0x0000KKLL, where KK < 0xE8 + * Thumb 32-bit: 0xKKLLMMNN, where KK >= 0xE8 + * + * There is no way to distinguish an ARM instruction in canonical representation + * from a Thumb instruction (just as these cannot be distinguished in memory). + * Where this distinction is important, it needs to be tracked separately. + * + * Note that values in the range 0x0000E800..0xE7FFFFFF intentionally do not + * represent any valid Thumb-2 instruction. For this range, + * __opcode_is_thumb32() and __opcode_is_thumb16() will both be false. + */ + +#ifdef CONFIG_CPU_ENDIAN_BE8 +#define __opcode_to_mem_arm(x) swab32(x) +#define __opcode_to_mem_thumb16(x) swab16(x) +#define __opcode_to_mem_thumb32(x) swahb32(x) +#else +#define __opcode_to_mem_arm(x) ((u32)(x)) +#define __opcode_to_mem_thumb16(x) ((u16)(x)) +#define __opcode_to_mem_thumb32(x) swahw32(x) +#endif + +#define __mem_to_opcode_arm(x) __opcode_to_mem_arm(x) +#define __mem_to_opcode_thumb16(x) __opcode_to_mem_thumb16(x) +#define __mem_to_opcode_thumb32(x) __opcode_to_mem_thumb32(x) + +/* Operations specific to Thumb opcodes */ + +/* Instruction size checks: */ +#define __opcode_is_thumb32(x) ((u32)(x) >= 0xE8000000UL) +#define __opcode_is_thumb16(x) ((u32)(x) < 0xE800UL) + +/* Operations to construct or split 32-bit Thumb instructions: */ +#define __opcode_thumb32_first(x) ((u16)((x) >> 16)) +#define __opcode_thumb32_second(x) ((u16)(x)) +#define __opcode_thumb32_compose(first, second) \ + (((u32)(u16)(first) << 16) | (u32)(u16)(second)) + +#endif /* ! __ARM_OPCODES_H */