From nobody Mon Feb 9 00:06:41 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1505240554012146.69376353980476; Tue, 12 Sep 2017 11:22:34 -0700 (PDT) Received: from localhost ([::1]:37993 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1drppR-0002q6-58 for importer@patchew.org; Tue, 12 Sep 2017 14:22:33 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43397) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1drph2-0003Qz-13 for qemu-devel@nongnu.org; Tue, 12 Sep 2017 14:13:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1drph0-0006RF-SQ for qemu-devel@nongnu.org; Tue, 12 Sep 2017 14:13:51 -0400 Received: from orth.archaic.org.uk ([2001:8b0:1d0::2]:37298) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1drpgx-0006Mo-3w; Tue, 12 Sep 2017 14:13:47 -0400 Received: from pm215 by orth.archaic.org.uk with local (Exim 4.89) (envelope-from ) id 1drpgq-00012z-9z; Tue, 12 Sep 2017 19:13:40 +0100 From: Peter Maydell To: qemu-arm@nongnu.org, qemu-devel@nongnu.org Date: Tue, 12 Sep 2017 19:13:48 +0100 Message-Id: <1505240046-11454-2-git-send-email-peter.maydell@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1505240046-11454-1-git-send-email-peter.maydell@linaro.org> References: <1505240046-11454-1-git-send-email-peter.maydell@linaro.org> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2001:8b0:1d0::2 Subject: [Qemu-devel] [PATCH 01/19] target/arm: Implement MSR/MRS access to NS banked registers X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: patches@linaro.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" In v8M the MSR and MRS instructions have extra register value encodings to allow secure code to access the non-secure banked version of various special registers. (We don't implement the MSPLIM_NS or PSPLIM_NS aliases, because we don't currently implement the stack limit registers at all.) Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson --- target/arm/helper.c | 110 ++++++++++++++++++++++++++++++++++++++++++++++++= ++++ 1 file changed, 110 insertions(+) diff --git a/target/arm/helper.c b/target/arm/helper.c index 4f41841..f4f2a87 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -8892,12 +8892,68 @@ uint32_t HELPER(v7m_mrs)(CPUARMState *env, uint32_t= reg) break; case 20: /* CONTROL */ return env->v7m.control[env->v7m.secure]; + case 0x94: /* CONTROL_NS */ + /* We have to handle this here because unprivileged Secure code + * can read the NS CONTROL register. + */ + if (!env->v7m.secure) { + return 0; + } + return env->v7m.control[M_REG_NS]; } =20 if (el =3D=3D 0) { return 0; /* unprivileged reads others as zero */ } =20 + if (arm_feature(env, ARM_FEATURE_M_SECURITY)) { + switch (reg) { + case 0x88: /* MSP_NS */ + if (!env->v7m.secure) { + return 0; + } + return env->v7m.other_ss_msp; + case 0x89: /* PSP_NS */ + if (!env->v7m.secure) { + return 0; + } + return env->v7m.other_ss_psp; + case 0x90: /* PRIMASK_NS */ + if (!env->v7m.secure) { + return 0; + } + return env->v7m.primask[M_REG_NS]; + case 0x91: /* BASEPRI_NS */ + if (!env->v7m.secure) { + return 0; + } + return env->v7m.basepri[M_REG_NS]; + case 0x93: /* FAULTMASK_NS */ + if (!env->v7m.secure) { + return 0; + } + return env->v7m.faultmask[M_REG_NS]; + case 0x98: /* SP_NS */ + { + /* This gives the non-secure SP selected based on whether we're + * currently in handler mode or not, using the NS CONTROL.SPSE= L. + */ + bool spsel =3D env->v7m.control[M_REG_NS] & R_V7M_CONTROL_SPSE= L_MASK; + + if (!env->v7m.secure) { + return 0; + } + if (!arm_v7m_is_handler_mode(env) && spsel) { + return env->v7m.other_ss_psp; + } else { + return env->v7m.other_ss_msp; + } + } + default: + break; + } + } + switch (reg) { case 8: /* MSP */ return (env->v7m.control[env->v7m.secure] & R_V7M_CONTROL_SPSEL_MA= SK) ? @@ -8936,6 +8992,60 @@ void HELPER(v7m_msr)(CPUARMState *env, uint32_t mask= reg, uint32_t val) return; } =20 + if (arm_feature(env, ARM_FEATURE_M_SECURITY)) { + switch (reg) { + case 0x88: /* MSP_NS */ + if (!env->v7m.secure) { + return; + } + env->v7m.other_ss_msp =3D val; + return; + case 0x89: /* PSP_NS */ + if (!env->v7m.secure) { + return; + } + env->v7m.other_ss_psp =3D val; + return; + case 0x90: /* PRIMASK_NS */ + if (!env->v7m.secure) { + return; + } + env->v7m.primask[M_REG_NS] =3D val & 1; + return; + case 0x91: /* BASEPRI_NS */ + if (!env->v7m.secure) { + return; + } + env->v7m.basepri[M_REG_NS] =3D val & 0xff; + return; + case 0x93: /* FAULTMASK_NS */ + if (!env->v7m.secure) { + return; + } + env->v7m.faultmask[M_REG_NS] =3D val & 1; + return; + case 0x98: /* SP_NS */ + { + /* This gives the non-secure SP selected based on whether we're + * currently in handler mode or not, using the NS CONTROL.SPSE= L. + */ + bool spsel =3D env->v7m.control[M_REG_NS] & R_V7M_CONTROL_SPSE= L_MASK; + + if (!env->v7m.secure) { + return; + } + if (!arm_v7m_is_handler_mode(env) && spsel) { + env->v7m.other_ss_psp =3D val; + } else { + env->v7m.other_ss_msp =3D val; + } + return; + } + default: + break; + } + } + switch (reg) { case 0 ... 7: /* xPSR sub-fields */ /* only APSR is actually writable */ --=20 2.7.4