From patchwork Fri Mar 21 12:53:33 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anup Patel X-Patchwork-Id: 3874301 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 5D1839F382 for ; Fri, 21 Mar 2014 13:53:25 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 84F842027D for ; Fri, 21 Mar 2014 13:53:24 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (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 5456920279 for ; Fri, 21 Mar 2014 13:53:23 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WQz0T-0005HY-RK; Fri, 21 Mar 2014 12:57:07 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1WQyzi-0004u2-Te; Fri, 21 Mar 2014 12:56:18 +0000 Received: from mail-pb0-f54.google.com ([209.85.160.54]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WQyyZ-0004jl-Li for linux-arm-kernel@lists.infradead.org; Fri, 21 Mar 2014 12:55:12 +0000 Received: by mail-pb0-f54.google.com with SMTP id ma3so2393268pbc.27 for ; Fri, 21 Mar 2014 05:54:46 -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=cZJOCfNDRs9qukoR8Xn+ZFHW0S9dE26o0dr3pfAtD4s=; b=A9R3WsbKhPNxUmiaBgihYHkRhZ/v6bCOc5SCBrxsB2NKISnZBmWdYX0ax24L1Ngddm bOsTdvqHC30g+9EVq4RmAZiXoy/KYoSlnBzBIYwvRRl4H1vQp/zbOPG8Kb29kT7pVZ4e 0DljN/4JEDDNb9kK2lKwWohcpf3oAF9FRLK6MLhHZTjF1VaMM+MC3auyubEt8B7DzKYA ZGx3Gtvk8ei1tbrvmB4w/z0MZE/doJjH0A2HAXrZQGKPzTWoMW2xboIWER74sCt7wRhu WU1DHPqrdkxsOyik3RMf1BGntTiH58/3Dd3DzJrRy4Bn7SJQSDTLGKiLL69Q/XmiFZ3L cMug== X-Gm-Message-State: ALoCoQm40ETy9YXvh8UlxfCKbh4Ai04RAM8E5/1U7FqGebq1oOzvUJuVZYcaeAv/73dBY6HdpOwO X-Received: by 10.66.240.4 with SMTP id vw4mr53620833pac.26.1395406486041; Fri, 21 Mar 2014 05:54:46 -0700 (PDT) Received: from pnqlab006.amcc.com ([182.73.239.130]) by mx.google.com with ESMTPSA id dk1sm9788981pbc.46.2014.03.21.05.54.42 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 21 Mar 2014 05:54:45 -0700 (PDT) From: Anup Patel To: kvmarm@lists.cs.columbia.edu Subject: [PATCH v5 10/11] ARM/ARM64: KVM: Emulate PSCI v0.2 CPU_SUSPEND Date: Fri, 21 Mar 2014 18:23:33 +0530 Message-Id: <1395406414-11707-11-git-send-email-anup.patel@linaro.org> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1395406414-11707-1-git-send-email-anup.patel@linaro.org> References: <1395406414-11707-1-git-send-email-anup.patel@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140321_085507_851621_964A07A6 X-CRM114-Status: GOOD ( 12.39 ) X-Spam-Score: -2.6 (--) Cc: Mark Rutland , linaro-kernel@lists.linaro.org, Anup Patel , Marc Zyngier , patches@apm.com, linux-arm-kernel@lists.infradead.org, Christoffer Dall , 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=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_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 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 for KVM we simply 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/) Even if we had stable DT-bindings for PSCI and CPUIDLE driver that uses PSCI CPU_SUSPEND then still we need to define SUSPEND states for KVM ARM/ARM64. Due to this, the CPU_SUSPEND emulation added by this patch only pause current VCPU and to wakeup a suspended VCPU we need to explicity call PSCI CPU_ON from Guest. Signed-off-by: Anup Patel Signed-off-by: Pranavkumar Sawargaonkar --- arch/arm/kvm/psci.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index 1e85452..e32ad10 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -52,6 +52,22 @@ static unsigned long psci_affinity_mask(unsigned long affinity_level) return affinity_mask; } +static unsigned long kvm_psci_vcpu_suspend(struct kvm_vcpu *vcpu) +{ + /* + * NOTE: Currently, we don't have any wakeup events for KVM + * hence VCPU suspend turns-out to be same as VCPU off request. + * This means to suspend a VCPU we simply set the pause flag + * and update VCPU registers as-per wakeup parameters provided + * via r2 & r3 (or x2 & x3). + */ + vcpu->arch.pause = true; + *vcpu_pc(vcpu) = *vcpu_reg(vcpu, 2); + *vcpu_reg(vcpu, 0) = *vcpu_reg(vcpu, 3); + + return KVM_PSCI_RET_SUCCESS; +} + static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu) { vcpu->arch.pause = true; @@ -195,6 +211,10 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu) */ val = 2; break; + case KVM_PSCI_0_2_FN_CPU_SUSPEND: + case KVM_PSCI_0_2_FN64_CPU_SUSPEND: + val = kvm_psci_vcpu_suspend(vcpu); + break; case KVM_PSCI_0_2_FN_CPU_OFF: kvm_psci_vcpu_off(vcpu); val = KVM_PSCI_RET_SUCCESS; @@ -232,10 +252,6 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu) val = KVM_PSCI_RET_SUCCESS; ret = 0; break; - case KVM_PSCI_0_2_FN_CPU_SUSPEND: - case KVM_PSCI_0_2_FN64_CPU_SUSPEND: - val = KVM_PSCI_RET_NI; - break; default: return -EINVAL; }