From nobody Tue Feb 10 18:55:38 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org ARC-Seal: i=1; a=rsa-sha256; t=1615205813; cv=none; d=zohomail.com; s=zohoarc; b=IsQ5ndMTV9Ln1eTxqpntMH/OTGMSNMTubQAsI45O3E6njQwEq0i5sC6hJo2r88vqmHEbPxGo+Vto4vH0hPp5dTgEt3yyt9iJDfp6/74Y1ofKVxtNlF0w1GY63w8a2DEXBK/lAyGopTHyYiAz9Yi8cE+ZXeerQ+fE+dKxkyXAngg= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1615205813; h=Content-Transfer-Encoding:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=wQMedtmuiVF25ZIbNf5sRaWPj1udfrgH9GTZS/7kwps=; b=hRh4kO2cbd2PJLaFZtika2qZ6YMy5CbiDByVWJmOt6jKXviiZCvPzWoLiCnYaaha513qAslFHmCI3xZ+E+q3XMUtznv2Cx1rXSPnc3NIy/FzqYxmycfGCXQekqJJbcbnS0UHZ8xKk600DLK+rvbEMXPLydhrNi6NAf0N3lDplGo= ARC-Authentication-Results: i=1; mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1615205813180271.76592340611126; Mon, 8 Mar 2021 04:16:53 -0800 (PST) Received: from localhost ([::1]:59892 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lJEoe-0007PZ-7Y for importer@patchew.org; Mon, 08 Mar 2021 07:16:52 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:33962) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lJEkG-0002zn-1x for qemu-devel@nongnu.org; Mon, 08 Mar 2021 07:12:20 -0500 Received: from mail.ilande.co.uk ([2001:41c9:1:41f::167]:45218 helo=mail.default.ilande.uk0.bigv.io) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lJEkE-0001w0-Hu for qemu-devel@nongnu.org; Mon, 08 Mar 2021 07:12:19 -0500 Received: from host86-148-34-47.range86-148.btcentralplus.com ([86.148.34.47] helo=kentang.home) by mail.default.ilande.uk0.bigv.io with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lJEk9-0004B0-6h; Mon, 08 Mar 2021 12:12:18 +0000 From: Mark Cave-Ayland To: qemu-devel@nongnu.org, laurent@vivier.eu Date: Mon, 8 Mar 2021 12:11:55 +0000 Message-Id: <20210308121155.2476-4-mark.cave-ayland@ilande.co.uk> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210308121155.2476-1-mark.cave-ayland@ilande.co.uk> References: <20210308121155.2476-1-mark.cave-ayland@ilande.co.uk> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-SA-Exim-Connect-IP: 86.148.34.47 X-SA-Exim-Mail-From: mark.cave-ayland@ilande.co.uk Subject: [PATCH v2 3/3] target/m68k: add M68K_FEATURE_UNALIGNED_DATA feature X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on mail.default.ilande.uk0.bigv.io) Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2001:41c9:1:41f::167; envelope-from=mark.cave-ayland@ilande.co.uk; helo=mail.default.ilande.uk0.bigv.io X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" According to the M68040UM Appendix D the requirement for data accesses to be word aligned is only for the 68000, 68008 and 68010 CPUs. Later CPUs from t= he 68020 onwards will allow unaligned data accesses but at the cost of being l= ess efficient. Add a new M68K_FEATURE_UNALIGNED_DATA feature to specify that data accesses= are not required to be word aligned, and don't perform the alignment on the sta= ck pointer when taking an exception if this feature is not selected. This is required because the MacOS DAFB driver attempts to call an A-trap with a byte-aligned stack pointer during initialisation and without this the stack pointer is off by one when the A-trap returns. Signed-off-by: Mark Cave-Ayland Reviewed-by: Laurent Vivier Reviewed-by: Richard Henderson --- target/m68k/cpu.c | 1 + target/m68k/cpu.h | 2 ++ target/m68k/op_helper.c | 5 ++++- 3 files changed, 7 insertions(+), 1 deletion(-) diff --git a/target/m68k/cpu.c b/target/m68k/cpu.c index 37d2ed9dc7..a14874b4da 100644 --- a/target/m68k/cpu.c +++ b/target/m68k/cpu.c @@ -161,6 +161,7 @@ static void m68020_cpu_initfn(Object *obj) m68k_set_feature(env, M68K_FEATURE_CAS); m68k_set_feature(env, M68K_FEATURE_CHK2); m68k_set_feature(env, M68K_FEATURE_MSP); + m68k_set_feature(env, M68K_FEATURE_UNALIGNED_DATA); } =20 /* diff --git a/target/m68k/cpu.h b/target/m68k/cpu.h index ce558e9b03..402c86c876 100644 --- a/target/m68k/cpu.h +++ b/target/m68k/cpu.h @@ -527,6 +527,8 @@ enum m68k_features { M68K_FEATURE_MOVEP, /* MOVEC insn. (from 68010) */ M68K_FEATURE_MOVEC, + /* Unaligned data accesses (680[2346]0) */ + M68K_FEATURE_UNALIGNED_DATA, }; =20 static inline int m68k_feature(CPUM68KState *env, int feature) diff --git a/target/m68k/op_helper.c b/target/m68k/op_helper.c index 59a6448296..3fa7b7e19e 100644 --- a/target/m68k/op_helper.c +++ b/target/m68k/op_helper.c @@ -348,7 +348,10 @@ static void m68k_interrupt_all(CPUM68KState *env, int = is_hw) cpu_m68k_set_sr(env, sr); sp =3D env->aregs[7]; =20 - sp &=3D ~1; + if (!m68k_feature(env, M68K_FEATURE_UNALIGNED_DATA)) { + sp &=3D ~1; + } + if (cs->exception_index =3D=3D EXCP_ACCESS) { if (env->mmu.fault) { cpu_abort(cs, "DOUBLE MMU FAULT\n"); --=20 2.20.1