From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C62E0C433F5 for ; Thu, 30 Sep 2021 18:33:15 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 88BA2615E5 for ; Thu, 30 Sep 2021 18:33:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 88BA2615E5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=OmC1NlJJ2IUXEBByf7yxIwl4m/+CdqVcOb0Fw/rT5NU=; b=Cofh92oCansm84 nFKSwewiQ/ZWv686yaqVxWsxnO1rc1wgn2LakI4nuBk/6ibpMKITxUkKwM6JKGM7LMoeGDcrs74+B zwaxYyhhlSEq/+rKhRrXvsk5+eZ4j7rJAffmn9xVaOytSqFOLFR6yQiV1pLOaR0Uhg7leqYgaxwEj plehYOK9WAm3Wyur5+rCVK72oNo13YOrEZEIFchjhY5B8ZoavFFNx9HuGCD0kF2NJDxJxG9eMav6l vSTKpYTnN4MnXdkPQgz8i1k/JgUviyrN+JJ3FuA52DMRx07dvmxB6bto6D1ZwXk5ke/EaRsJYWUOt fqK4re70peXJkK3zvZLw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mW0pD-00FaGc-1e; Thu, 30 Sep 2021 18:30:33 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mW0bj-00FUao-S2 for linux-arm-kernel@lists.infradead.org; Thu, 30 Sep 2021 18:16:37 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id 05A43615A2; Thu, 30 Sep 2021 18:16:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1633025795; bh=NEZrppPq+QD20ya5LgSGLQO67xyDmKzQYTQykBzQU/0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=a5LL+x8aO4LymMqQLCV2Vqvwf1/QF7nuMpiTlIPD2iYZeX1RgvZ60iWprOSAFGLe6 5TdmtQ8yRVP40NcXcaqDR18shLPUDnI/YEZkmpkFpoYqLX5iaks6Klo5SzOlBArWNC TbCKvnsJoxMF/N21SzgUwxTEk6aG8a3Mib0oOtDFdKNXxK1lLUYSsis223/QScAvlO he06tW8IHwjzkoBNaD9scU+N3HNACSACG3+CmcRAwpFJ+GqIMQRLNAkCvKcvr56faR icnq3ybFPJvZoHu3axIftQhb0p7+vAtFw6pakUaUu7T0kSyxMwJ8Hv8bRXL0zwCh77 kVwURQEfdQHCg== From: Mark Brown To: Catalin Marinas , Will Deacon , Shuah Khan , Shuah Khan Cc: Alan Hayward , Luis Machado , Salil Akerkar , Basant Kumar Dwivedi , Szabolcs Nagy , linux-arm-kernel@lists.infradead.org, linux-kselftest@vger.kernel.org, Mark Brown Subject: [PATCH v1 21/38] arm64/sme: Implement SVCR context switching Date: Thu, 30 Sep 2021 19:11:27 +0100 Message-Id: <20210930181144.10029-22-broonie@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210930181144.10029-1-broonie@kernel.org> References: <20210930181144.10029-1-broonie@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3708; h=from:subject; bh=NEZrppPq+QD20ya5LgSGLQO67xyDmKzQYTQykBzQU/0=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBhVf3SzEalELgFwPycvepn28xA3wR8PBsdOEQRmXvz HHsPzI+JATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCYVX90gAKCRAk1otyXVSH0PLRB/ 97UL01AdBiCRyZ9KkkmX+sI8w0ec701Rek03oR1mZedxfMb8hBrCeXbNsI24GvrTty75IHiBgnDroS Cbr9pqMWFj2qXOjF3abp02tHXZDE3X0wFZpRxoO6X65NO89e+crXkRP5p0OUsOKkO/MNZ5gkQALTce lYppXCPiYC4UdVKoSG6hl1rB2UTSF4TnJqqgobGtV+4O/bkjYdAJS/7ZFvbxq9N6jIAv01XBOcR6Pe H2w8Nj8xd5icgVwvl27qUAH4BUJZ/k1siVPy6XKZkugW/xEEOUCBaAcpgbCyIKoRn4+cnIo4Cdgas4 quwkOZd+02bgPbza/YOcS8nlBRrL1q X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210930_111635_989022_1C6044D3 X-CRM114-Status: GOOD ( 12.28 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org In SME the use of both streaming SVE mode and ZA are tracked through PSTATE.SM and PSTATE.ZA, visible through the system register SVCR. In order to context switch the floating point state for SME we need to context switch the contents of this register as part of context switching the floating point state. Since changing the vector length exits streaming SVE mode and disables ZA we also make sure we update SVCR appropraitely when setting vector length, and similarly ensure that new threads have streaming SVE mode and ZA disabled. Signed-off-by: Mark Brown --- arch/arm64/include/asm/processor.h | 1 + arch/arm64/include/asm/thread_info.h | 1 + arch/arm64/kernel/fpsimd.c | 11 +++++++++++ arch/arm64/kernel/process.c | 2 ++ 4 files changed, 15 insertions(+) diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 51eca2513cb5..3c235e165725 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -168,6 +168,7 @@ struct thread_struct { u64 mte_ctrl; #endif u64 sctlr_user; + u64 svcr; u64 tpidr2_el0; }; diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index 5c4355204f4a..03cb88f63317 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -81,6 +81,7 @@ int arch_dup_task_struct(struct task_struct *dst, #define TIF_SVE_VL_INHERIT 24 /* Inherit SVE vl_onexec across exec */ #define TIF_SSBD 25 /* Wants SSB mitigation */ #define TIF_TAGGED_ADDR 26 /* Allow tagged user addresses */ +#define TIF_SME 27 /* SME in use */ #define TIF_SME_VL_INHERIT 28 /* Inherit SME vl_onexec across exec */ #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index e673a1d6a618..25193fd04860 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -355,6 +355,9 @@ static void task_fpsimd_load(void) WARN_ON(!system_supports_fpsimd()); WARN_ON(!have_cpu_fpsimd_context()); + if (IS_ENABLED(CONFIG_ARM64_SME) && test_thread_flag(TIF_SME)) + write_sysreg_s(current->thread.svcr, SYS_SVCR_EL0); + if (IS_ENABLED(CONFIG_ARM64_SVE) && test_thread_flag(TIF_SVE)) { sve_set_vq(sve_vq_from_vl(task_get_sve_vl(current)) - 1); sve_load_state(sve_pffr(¤t->thread), @@ -380,6 +383,10 @@ static void fpsimd_save(void) if (test_thread_flag(TIF_FOREIGN_FPSTATE)) return; + if (IS_ENABLED(CONFIG_ARM64_SME) && + test_thread_flag(TIF_SME)) + current->thread.svcr = read_sysreg_s(SYS_SVCR_EL0); + if (IS_ENABLED(CONFIG_ARM64_SVE) && test_thread_flag(TIF_SVE)) { if (WARN_ON(sve_get_vl() != last->sve_vl)) { @@ -734,6 +741,10 @@ int vec_set_vector_length(struct task_struct *task, enum vec_type type, if (test_and_clear_tsk_thread_flag(task, TIF_SVE)) sve_to_fpsimd(task); + if (system_supports_sme() && type == ARM64_VEC_SME) + task->thread.svcr &= ~(SYS_SVCR_EL0_SM_MASK | + SYS_SVCR_EL0_ZA_MASK); + if (task == current) put_cpu_fpsimd_context(); diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 0640b51d4289..c5544b669a58 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -307,6 +307,8 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) dst->thread.sve_state = NULL; clear_tsk_thread_flag(dst, TIF_SVE); + dst->thread.svcr = 0; + /* clear any pending asynchronous tag fault raised by the parent */ clear_tsk_thread_flag(dst, TIF_MTE_ASYNC_FAULT); -- 2.20.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel