From patchwork Sun May 25 18:18:57 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoffer Dall X-Patchwork-Id: 4238931 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 017799F32B for ; Sun, 25 May 2014 18:23:58 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1C2A4201DE for ; Sun, 25 May 2014 18:23:57 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4300A20179 for ; Sun, 25 May 2014 18:23:56 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Wod31-00071j-HS; Sun, 25 May 2014 18:21:27 +0000 Received: from mail-la0-f46.google.com ([209.85.215.46]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Wod1W-0004pH-VK for linux-arm-kernel@lists.infradead.org; Sun, 25 May 2014 18:19:55 +0000 Received: by mail-la0-f46.google.com with SMTP id ec20so3732634lab.19 for ; Sun, 25 May 2014 11:19:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=kZTK8ABKRNnnpYW0ucTEKo0+R8v8WzypvYo/8Lrk6cw=; b=cSpQ88vbAZdv1OEBBi7sUr22FxuR1pCAM4WaEqNdUDjuV/t4vSoGTvSHm7xH5KlcUz 7YovlhJurPvTSCmhDiKboDRi+bPm9eeaohVNclaLAVLKDjzUHgARBNB4Xv9KVztBaGz0 nEx4O8fPKNcPVO3An5hePF82mO7OWLJBvV8NDFA0E2FcRW+zNyuM8VGxAD2iOPbAJlKW Iag4qZT9Q8I+3JN5JTSdbYIQ/2OKlY5WrAI3Mi+xossCI00ZwDaa3METnQIYt3KE+zEZ ypliixkEwFVbWQ/CXsekVc7ITWCTgxvy/Ri13Y2JzEmLm094WB1EgAT4iSnw2V2jbSk4 q/kA== X-Gm-Message-State: ALoCoQlM8wwtQYZYO9u4q9bOv1OdsijnZ2f1U4pbio8w34603nDOjV6RNmnhi9T/52VQ9CqgvnNy X-Received: by 10.152.121.39 with SMTP id lh7mr13468403lab.7.1401041972603; Sun, 25 May 2014 11:19:32 -0700 (PDT) Received: from localhost.localdomain (x1-6-b8-c7-5d-cb-5a-ca.cpe.webspeed.dk. [2.104.6.253]) by mx.google.com with ESMTPSA id o1sm9683895lbw.27.2014.05.25.11.19.30 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sun, 25 May 2014 11:19:31 -0700 (PDT) From: Christoffer Dall To: Paolo Bonzini , Gleb Natapov Subject: [PATCH 11/16] ARM/ARM64: KVM: Emulate PSCI v0.2 CPU_SUSPEND Date: Sun, 25 May 2014 20:18:57 +0200 Message-Id: <1401041942-23471-12-git-send-email-christoffer.dall@linaro.org> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1401041942-23471-1-git-send-email-christoffer.dall@linaro.org> References: <1401041942-23471-1-git-send-email-christoffer.dall@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140525_111955_214117_9C6DD430 X-CRM114-Status: GOOD ( 15.30 ) X-Spam-Score: -0.7 (/) Cc: Peter Maydell , Anup Patel , kvm@vger.kernel.org, Marc Zyngier , Ashwin Chaugule , Christoffer Dall , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Pranavkumar Sawargaonkar X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.5 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Anup Patel This patch adds emulation of PSCI v0.2 CPU_SUSPEND function call for KVM ARM/ARM64. This is a CPU-level function call which can suspend current CPU or current CPU cluster. We don't have VCPU clusters in KVM so we only suspend the current VCPU. The CPU_SUSPEND emulation is not tested much because currently there is no CPUIDLE driver in Linux kernel that uses PSCI CPU_SUSPEND. The PSCI CPU_SUSPEND implementation in ARM64 kernel was tested using a Simple CPUIDLE driver which is not published due to unstable DT-bindings for PSCI. (For more info, http://lwn.net/Articles/574950/) For simplicity, we implement CPU_SUSPEND emulation similar to WFI (Wait-for-interrupt) emulation and we also treat power-down request to be same as stand-by request. This is consistent with section 5.4.1 and section 5.4.2 of PSCI v0.2 specification. Signed-off-by: Anup Patel Signed-off-by: Pranavkumar Sawargaonkar Acked-by: Christoffer Dall Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/kvm/psci.c | 28 ++++++++++++++++++++++++---- 1 file changed, 24 insertions(+), 4 deletions(-) diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index 1067579..09cf377 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -37,6 +37,26 @@ static unsigned long psci_affinity_mask(unsigned long affinity_level) return 0; } +static unsigned long kvm_psci_vcpu_suspend(struct kvm_vcpu *vcpu) +{ + /* + * NOTE: For simplicity, we make VCPU suspend emulation to be + * same-as WFI (Wait-for-interrupt) emulation. + * + * This means for KVM the wakeup events are interrupts and + * this is consistent with intended use of StateID as described + * in section 5.4.1 of PSCI v0.2 specification (ARM DEN 0022A). + * + * Further, we also treat power-down request to be same as + * stand-by request as-per section 5.4.2 clause 3 of PSCI v0.2 + * specification (ARM DEN 0022A). This means all suspend states + * for KVM will preserve the register state. + */ + kvm_vcpu_block(vcpu); + + return PSCI_RET_SUCCESS; +} + static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu) { vcpu->arch.pause = true; @@ -183,6 +203,10 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu) */ val = 2; break; + case PSCI_0_2_FN_CPU_SUSPEND: + case PSCI_0_2_FN64_CPU_SUSPEND: + val = kvm_psci_vcpu_suspend(vcpu); + break; case PSCI_0_2_FN_CPU_OFF: kvm_psci_vcpu_off(vcpu); val = PSCI_RET_SUCCESS; @@ -235,10 +259,6 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu) val = PSCI_RET_INTERNAL_FAILURE; ret = 0; break; - case PSCI_0_2_FN_CPU_SUSPEND: - case PSCI_0_2_FN64_CPU_SUSPEND: - val = PSCI_RET_NOT_SUPPORTED; - break; default: return -EINVAL; }