From patchwork Thu Jan 10 16:06:45 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 1961061 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork2.kernel.org (Postfix) with ESMTP id 79D64DF264 for ; Thu, 10 Jan 2013 16:11:36 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TtKf8-00084L-9A; Thu, 10 Jan 2013 16:07:26 +0000 Received: from service87.mimecast.com ([91.220.42.44]) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TtKf2-00082C-Q0 for linux-arm-kernel@lists.infradead.org; Thu, 10 Jan 2013 16:07:22 +0000 Received: from cam-owa2.Emea.Arm.com (fw-tnat.cambridge.arm.com [217.140.96.21]) by service87.mimecast.com; Thu, 10 Jan 2013 16:07:17 +0000 Received: from e102391-lin.cambridge.arm.com ([10.1.255.212]) by cam-owa2.Emea.Arm.com with Microsoft SMTPSVC(6.0.3790.3959); Thu, 10 Jan 2013 16:07:16 +0000 From: Marc Zyngier To: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org Subject: [PATCH v2 2/2] ARM: KVM: Power State Coordination Interface implementation Date: Thu, 10 Jan 2013 16:06:45 +0000 Message-Id: <1357834005-23843-3-git-send-email-marc.zyngier@arm.com> X-Mailer: git-send-email 1.8.1 In-Reply-To: <1357834005-23843-1-git-send-email-marc.zyngier@arm.com> References: <1357834005-23843-1-git-send-email-marc.zyngier@arm.com> X-OriginalArrivalTime: 10 Jan 2013 16:07:16.0611 (UTC) FILETIME=[8F67CD30:01CDEF4C] X-MC-Unique: 113011016071718301 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130110_110721_215491_553A7B67 X-CRM114-Status: GOOD ( 22.22 ) X-Spam-Score: -2.6 (--) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-2.6 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [91.220.42.44 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Implement the PSCI specification (ARM DEN 0022A) to control virtual CPUs being "powered" on or off. PSCI/KVM is detected using the KVM_CAP_ARM_PSCI capability. A virtual CPU can now be initialized in a "powered off" state, using the KVM_ARM_VCPU_POWER_OFF feature flag. The guest can use either SMC or HVC to execute a PSCI function. Signed-off-by: Marc Zyngier --- Documentation/virtual/kvm/api.txt | 4 ++ arch/arm/include/asm/kvm_emulate.h | 5 +++ arch/arm/include/asm/kvm_host.h | 2 +- arch/arm/include/asm/kvm_psci.h | 23 ++++++++++ arch/arm/include/uapi/asm/kvm.h | 16 +++++++ arch/arm/kvm/Makefile | 2 +- arch/arm/kvm/arm.c | 26 +++++++---- arch/arm/kvm/psci.c | 90 ++++++++++++++++++++++++++++++++++++++ include/uapi/linux/kvm.h | 1 + 9 files changed, 158 insertions(+), 11 deletions(-) create mode 100644 arch/arm/include/asm/kvm_psci.h create mode 100644 arch/arm/kvm/psci.c diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 497fd48..e0fa0ea 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2185,6 +2185,10 @@ return ENOEXEC for that vcpu. Note that because some registers reflect machine topology, all vcpus should be created before this ioctl is invoked. +Possible features: + - KVM_ARM_VCPU_POWER_OFF: Starts the CPU in a power-off state. + Depends on KVM_CAP_ARM_PSCI. + 4.78 KVM_GET_REG_LIST diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h index 375795b..eb07342 100644 --- a/arch/arm/include/asm/kvm_emulate.h +++ b/arch/arm/include/asm/kvm_emulate.h @@ -34,6 +34,11 @@ void kvm_inject_undefined(struct kvm_vcpu *vcpu); void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr); void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr); +static inline bool vcpu_mode_is_32bit(struct kvm_vcpu *vcpu) +{ + return 1; +} + static inline u32 *vcpu_pc(struct kvm_vcpu *vcpu) { return (u32 *)&vcpu->arch.regs.usr_regs.ARM_pc; diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 14a71bb..b8eb3e0 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -31,7 +31,7 @@ #define KVM_COALESCED_MMIO_PAGE_OFFSET 1 #define KVM_HAVE_ONE_REG -#define KVM_VCPU_MAX_FEATURES 0 +#define KVM_VCPU_MAX_FEATURES 1 /* We don't currently support large pages. */ #define KVM_HPAGE_GFN_SHIFT(x) 0 diff --git a/arch/arm/include/asm/kvm_psci.h b/arch/arm/include/asm/kvm_psci.h new file mode 100644 index 0000000..992d7f1 --- /dev/null +++ b/arch/arm/include/asm/kvm_psci.h @@ -0,0 +1,23 @@ +/* + * Copyright (C) 2012 - ARM Ltd + * Author: Marc Zyngier + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#ifndef __ARM_KVM_PSCI_H__ +#define __ARM_KVM_PSCI_H__ + +int kvm_psci_call(struct kvm_vcpu *vcpu); + +#endif /* __ARM_KVM_PSCI_H__ */ diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h index 94e893b..972b90d 100644 --- a/arch/arm/include/uapi/asm/kvm.h +++ b/arch/arm/include/uapi/asm/kvm.h @@ -81,6 +81,8 @@ struct kvm_regs { #define KVM_VGIC_V2_DIST_SIZE 0x1000 #define KVM_VGIC_V2_CPU_SIZE 0x2000 +#define KVM_ARM_VCPU_POWER_OFF 0 /* CPU is started in OFF state */ + struct kvm_vcpu_init { __u32 target; __u32 features[7]; @@ -161,4 +163,18 @@ struct kvm_arch_memory_slot { /* Highest supported SPI, from VGIC_NR_IRQS */ #define KVM_ARM_IRQ_GIC_MAX 127 +/* PSCI interface */ +#define KVM_PSCI_FN_BASE 0x95c1ba5e +#define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n)) + +#define KVM_PSCI_FN_CPU_SUSPEND KVM_PSCI_FN(0) +#define KVM_PSCI_FN_CPU_OFF KVM_PSCI_FN(1) +#define KVM_PSCI_FN_CPU_ON KVM_PSCI_FN(2) +#define KVM_PSCI_FN_MIGRATE KVM_PSCI_FN(3) + +#define KVM_PSCI_RET_SUCCESS 0 +#define KVM_PSCI_RET_NI ((unsigned long)-1) +#define KVM_PSCI_RET_INVAL ((unsigned long)-2) +#define KVM_PSCI_RET_DENIED ((unsigned long)-3) + #endif /* __ARM_KVM_H__ */ diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile index 43c4cad..6a2d571 100644 --- a/arch/arm/kvm/Makefile +++ b/arch/arm/kvm/Makefile @@ -18,6 +18,6 @@ kvm-arm-y = $(addprefix ../../../virt/kvm/, kvm_main.o coalesced_mmio.o) obj-y += kvm-arm.o init.o interrupts.o obj-y += arm.o guest.o mmu.o emulate.o reset.o -obj-y += coproc.o coproc_a15.o mmio.o decode.o +obj-y += coproc.o coproc_a15.o mmio.o decode.o psci.o obj-$(CONFIG_KVM_ARM_VGIC) += vgic.o obj-$(CONFIG_KVM_ARM_TIMER) += arch_timer.o diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index a28e49d..4d5ed244 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -43,6 +43,7 @@ #include #include #include +#include #include #ifdef REQUIRES_VIRT @@ -192,6 +193,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_SYNC_MMU: case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: case KVM_CAP_ONE_REG: + case KVM_CAP_ARM_PSCI: r = 1; break; case KVM_CAP_COALESCED_MMIO: @@ -496,21 +498,18 @@ static int handle_svc_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run) static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run) { - /* - * Guest called HVC instruction: - * Let it know we don't want that by injecting an undefined exception. - */ - kvm_debug("hvc: %x (at %08x)", vcpu->arch.hsr & ((1 << 16) - 1), - *vcpu_pc(vcpu)); - kvm_debug(" HSR: %8x", vcpu->arch.hsr); + if (!kvm_psci_call(vcpu)) + return 1; + kvm_inject_undefined(vcpu); return 1; } static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run) { - /* We don't support SMC; don't do that. */ - kvm_debug("smc: at %08x", *vcpu_pc(vcpu)); + if (!kvm_psci_call(vcpu)) + return 1; + kvm_inject_undefined(vcpu); return 1; } @@ -660,6 +659,15 @@ static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) return ret; } + /* + * Handle the "start in power-off" case by calling into the + * PSCI code. + */ + if (test_and_clear_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) { + *vcpu_reg(vcpu, 0) = KVM_PSCI_FN_CPU_OFF; + kvm_psci_call(vcpu); + } + return 0; } diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c new file mode 100644 index 0000000..4a1c4f0 --- /dev/null +++ b/arch/arm/kvm/psci.c @@ -0,0 +1,90 @@ +/* + * Copyright (C) 2012 - ARM Ltd + * Author: Marc Zyngier + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include + +#include +#include + +static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu) +{ + wait_queue_head_t *wq = kvm_arch_vcpu_wq(vcpu); + + vcpu->arch.pause = true; + + wait_event_interruptible(*wq, !vcpu->arch.pause); +} + +static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) +{ + struct kvm *kvm = source_vcpu->kvm; + struct kvm_vcpu *vcpu; + wait_queue_head_t *wq; + unsigned long cpu_id; + phys_addr_t target_pc; + + cpu_id = *vcpu_reg(source_vcpu, 1); + if (vcpu_mode_is_32bit(source_vcpu)) + cpu_id &= ~((u32) 0); + + if (cpu_id >= atomic_read(&kvm->online_vcpus)) + return KVM_PSCI_RET_INVAL; + + target_pc = *vcpu_reg(source_vcpu, 2); + + vcpu = kvm_get_vcpu(kvm, cpu_id); + + wq = kvm_arch_vcpu_wq(vcpu); + if (!waitqueue_active(wq)) + return KVM_PSCI_RET_INVAL; + + kvm_reset_vcpu(vcpu); + *vcpu_pc(vcpu) = target_pc; + vcpu->arch.pause = false; + smp_mb(); /* Make sure the above is visible */ + + wake_up_interruptible(wq); + + return KVM_PSCI_RET_SUCCESS; +} + +int kvm_psci_call(struct kvm_vcpu *vcpu) +{ + unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); + unsigned long val; + + switch (psci_fn) { + case KVM_PSCI_FN_CPU_OFF: + kvm_psci_vcpu_off(vcpu); + val = KVM_PSCI_RET_SUCCESS; + break; + case KVM_PSCI_FN_CPU_ON: + val = kvm_psci_vcpu_on(vcpu); + break; + case KVM_PSCI_FN_CPU_SUSPEND: + case KVM_PSCI_FN_MIGRATE: + val = KVM_PSCI_RET_NI; + break; + + default: + return -1; + } + + *vcpu_reg(vcpu, 0) = val; + return 0; +} diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 1f68151..9ff7f70 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -637,6 +637,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_PPC_BOOKE_WATCHDOG 83 #define KVM_CAP_PPC_HTAB_FD 84 #define KVM_CAP_ARM_SET_DEVICE_ADDR 85 +#define KVM_CAP_ARM_PSCI 86 #ifdef KVM_CAP_IRQ_ROUTING