From nobody Tue May 6 20:21:39 2025
Delivered-To: importer@patchew.org
Received-SPF: pass (zoho.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;
Authentication-Results: mx.zohomail.com;
dkim=fail;
spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted
sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org;
dmarc=fail(p=none dis=none) header.from=linaro.org
ARC-Seal: i=1; a=rsa-sha256; t=1556557958; cv=none;
d=zoho.com; s=zohoarc;
b=mdaAZrYRn1ZZXk687fARb7M6JC2MRz/4KI7JeJ2dnzlXGA8jmHzEWCll9r6XU4noLJWWtL6/AHXZdsPugGcQyCHIc4QKq0Tc3Kmy3TB270ob9IA0p8JgngWGhfeIc3E4EKQla6HR0ukwjiwKMSo8+Zt3SzXxtDEtFlf+6/w9DpA=
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com;
s=zohoarc;
t=1556557958;
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:ARC-Authentication-Results;
bh=3hCqKWhEs+uyed/mP56baIBgXAfI++APiWRLJhSExvw=;
b=eqJsnTzWp9jRyG/DzvSDpU0AEH5KiWZy/ynKZUXRGk9Dx1tmIP0CYy37+oIRunCoKtnsIuQUjaQbEhSXc//bMh09lo21C4b27tPJEYqr6LsRELu1ZbeAQZs30i4vX1FwXznC+31tRrjy0tTsjaa/NZUDE7YJRBZxQFIhiuA6zcA=
ARC-Authentication-Results: i=1; mx.zoho.com;
dkim=fail;
spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted
sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org;
dmarc=fail header.from=<peter.maydell@linaro.org> (p=none dis=none)
header.from=<peter.maydell@linaro.org>
Return-Path: <qemu-devel-bounces+importer=patchew.org@nongnu.org>
Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by
mx.zohomail.com
with SMTPS id 1556557958714776.6863176316134;
Mon, 29 Apr 2019 10:12:38 -0700 (PDT)
Received: from localhost ([127.0.0.1]:60748 helo=lists.gnu.org)
by lists.gnu.org with esmtp (Exim 4.71)
(envelope-from <qemu-devel-bounces+importer=patchew.org@nongnu.org>)
id 1hL9pN-0005NZ-Ae
for importer@patchew.org; Mon, 29 Apr 2019 13:12:29 -0400
Received: from eggs.gnu.org ([209.51.188.92]:34160)
by lists.gnu.org with esmtp (Exim 4.71)
(envelope-from <peter.maydell@linaro.org>) id 1hL9eN-0004Pl-Uf
for qemu-devel@nongnu.org; Mon, 29 Apr 2019 13:01:10 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
(envelope-from <peter.maydell@linaro.org>) id 1hL9eI-0006VI-GK
for qemu-devel@nongnu.org; Mon, 29 Apr 2019 13:01:04 -0400
Received: from mail-wr1-x442.google.com ([2a00:1450:4864:20::442]:36483)
by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16)
(Exim 4.71) (envelope-from <peter.maydell@linaro.org>)
id 1hL9eE-0006Bn-GO
for qemu-devel@nongnu.org; Mon, 29 Apr 2019 13:01:00 -0400
Received: by mail-wr1-x442.google.com with SMTP id o4so5177805wra.3
for <qemu-devel@nongnu.org>; Mon, 29 Apr 2019 10:00:42 -0700 (PDT)
Received: from orth.archaic.org.uk (orth.archaic.org.uk. [81.2.115.148])
by smtp.gmail.com with ESMTPSA id a13sm36896wmj.39.2019.04.29.10.00.40
for <qemu-devel@nongnu.org>
(version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);
Mon, 29 Apr 2019 10:00:41 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google;
h=from:to:subject:date:message-id:in-reply-to:references:mime-version
:content-transfer-encoding;
bh=3hCqKWhEs+uyed/mP56baIBgXAfI++APiWRLJhSExvw=;
b=YajaLebr2q7j6iLHUun3YVVHQEIWyb80UqcvVMn6EM5JmrAR1gJy5nmEDSyzlrcewv
4SdG2atfrQAWnqPEKOqq24P+eQ9Lt28jnwqKVN5oiEP8BpKgIz9o+PCoefSmV3767DWY
3vu9vRwOAkqM7MZR7LzSSKfBvTqWQxoW84xRX/MDcaiBgbkiietxVRrerECTNd4K/kHx
1GAzVLMDgC6U8pky+XP1aRBb/WwZHRvCTqOKn9peQxz4KBlViwfJRE8BDGpawKxON/1W
mLtDmhCUOtUdRdeGapzyqlwyvq1N06VH+eDGw1xVquEq/YAo6vPA0VGLnGvdeGJ5d3Gk
UrnQ==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=1e100.net; s=20161025;
h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to
:references:mime-version:content-transfer-encoding;
bh=3hCqKWhEs+uyed/mP56baIBgXAfI++APiWRLJhSExvw=;
b=O8R9vhNeNvRwP7Ni8IOKCbpfY+tyx4agg/ZBiIVqDCunGLjuDVnMIvTAKBK5kPoPuF
NcfeQRNso0oC0qo5whgbqoVhM8rkRVtZ8GPOoDFgWm3DAo4eEFNoXcsXxQuovH/ry+0E
AgpTnUEpGKS8hQFWL+BHki8cBMXsVG/kDL6yP+25weU3xkOmxIWQKGG08R0DcybstAsx
OToDTeAG1dhhGkSJcaoRroBzPmlNSOWq4vx1i221WbhutLspPSmdJX3DG8dLC/RyWAql
gmsyyrQvv64QJTv3KPOVfwh964kzWvIVl4EIpfglijwhKxDGTs7E5l5EFP9Mqo7nCTzL
QgLw==
X-Gm-Message-State: APjAAAUWAHsuqmND8YMMbtkvjTUtw2WRUIdmK98+PFDVDu5SQLS7r6hQ
Pq8VeSOntHMno/bd7lIpIYvXnQYD6fY=
X-Google-Smtp-Source:
APXvYqwzyHH1SLKerq7Uy9ZpnU6kU3kdfj6LA0T5koz25AD5rd0842mkiXb7MiwG+ve3zJpsJJ46yA==
X-Received: by 2002:adf:db05:: with SMTP id s5mr10651136wri.247.1556557241813;
Mon, 29 Apr 2019 10:00:41 -0700 (PDT)
From: Peter Maydell <peter.maydell@linaro.org>
To: qemu-devel@nongnu.org
Date: Mon, 29 Apr 2019 17:59:55 +0100
Message-Id: <20190429170030.11323-8-peter.maydell@linaro.org>
X-Mailer: git-send-email 2.20.1
In-Reply-To: <20190429170030.11323-1-peter.maydell@linaro.org>
References: <20190429170030.11323-1-peter.maydell@linaro.org>
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable
X-detected-operating-system: by eggs.gnu.org: Genre and OS details not
recognized.
X-Received-From: 2a00:1450:4864:20::442
Subject: [Qemu-devel] [PULL 07/42] target/arm: Disable most VFP sysregs for
M-profile
X-BeenThere: qemu-devel@nongnu.org
X-Mailman-Version: 2.1.21
Precedence: list
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel/>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org
Sender: "Qemu-devel" <qemu-devel-bounces+importer=patchew.org@nongnu.org>
X-ZohoMail-DKIM: fail (Header signature does not verify)
Content-Type: text/plain; charset="utf-8"
The only "system register" that M-profile floating point exposes
via the VMRS/VMRS instructions is FPSCR, and it does not have
the odd special case for rd=3D=3D15. Add a check to ensure we only
expose FPSCR.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20190416125744.27770-5-peter.maydell@linaro.org
---
target/arm/translate.c | 19 +++++++++++++++++--
1 file changed, 17 insertions(+), 2 deletions(-)
diff --git a/target/arm/translate.c b/target/arm/translate.c
index 4ea4018e2b8..a9784535069 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -3513,12 +3513,27 @@ static int disas_vfp_insn(DisasContext *s, uint32_t=
insn)
}
}
} else { /* !dp */
+ bool is_sysreg;
+
if ((insn & 0x6f) !=3D 0x00)
return 1;
rn =3D VFP_SREG_N(insn);
+
+ is_sysreg =3D extract32(insn, 21, 1);
+
+ if (arm_dc_feature(s, ARM_FEATURE_M)) {
+ /*
+ * The only M-profile VFP vmrs/vmsr sysreg is FPSCR.
+ * Writes to R15 are UNPREDICTABLE; we choose to undef.
+ */
+ if (is_sysreg && (rd =3D=3D 15 || (rn >> 1) !=3D ARM_V=
FP_FPSCR)) {
+ return 1;
+ }
+ }
+
if (insn & ARM_CP_RW_BIT) {
/* vfp->arm */
- if (insn & (1 << 21)) {
+ if (is_sysreg) {
/* system register */
rn >>=3D 1;
=20
@@ -3585,7 +3600,7 @@ static int disas_vfp_insn(DisasContext *s, uint32_t i=
nsn)
}
} else {
/* arm->vfp */
- if (insn & (1 << 21)) {
+ if (is_sysreg) {
rn >>=3D 1;
/* system register */
switch (rn) {
--=20
2.20.1