From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-6.0 required=5.0 tests=MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI,SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id B8A027D2F0 for ; Sat, 3 Aug 2019 11:21:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389628AbfHCLVf (ORCPT ); Sat, 3 Aug 2019 07:21:35 -0400 Received: from inca-roads.misterjones.org ([213.251.177.50]:37015 "EHLO inca-roads.misterjones.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389618AbfHCLVf (ORCPT ); Sat, 3 Aug 2019 07:21:35 -0400 X-Greylist: delayed 454 seconds by postgrey-1.27 at vger.kernel.org; Sat, 03 Aug 2019 07:21:33 EDT Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why) by cheepnis.misterjones.org with esmtpsa (TLSv1.2:AES256-GCM-SHA384:256) (Exim 4.80) (envelope-from ) id 1hts6I-0007Dy-TI; Sat, 03 Aug 2019 13:21:27 +0200 Date: Sat, 3 Aug 2019 12:21:24 +0100 From: Marc Zyngier To: Steven Price Cc: Catalin Marinas , Paolo Bonzini , Radim =?UTF-8?B?S3LEjW3DocWZ?= , Russell King , Will Deacon , James Morse , Julien Thierry , Suzuki K Pouloze , kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/9] KVM: arm64: Implement PV_FEATURES call Message-ID: <20190803122124.7700f700@why> In-Reply-To: <20190802145017.42543-4-steven.price@arm.com> References: <20190802145017.42543-1-steven.price@arm.com> <20190802145017.42543-4-steven.price@arm.com> Organization: Approximate X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: steven.price@arm.com, catalin.marinas@arm.com, pbonzini@redhat.com, rkrcmar@redhat.com, linux@armlinux.org.uk, will@kernel.org, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on cheepnis.misterjones.org); SAEximRunCond expanded to false Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Fri, 2 Aug 2019 15:50:11 +0100 Steven Price wrote: > This provides a mechanism for querying which paravirtualized features > are available in this hypervisor. > > Also add the header file which defines the ABI for the paravirtualized > clock features we're about to add. > > Signed-off-by: Steven Price > --- > arch/arm64/include/asm/pvclock-abi.h | 20 ++++++++++++++++++++ > include/linux/arm-smccc.h | 14 ++++++++++++++ > virt/kvm/arm/hypercalls.c | 9 +++++++++ > 3 files changed, 43 insertions(+) > create mode 100644 arch/arm64/include/asm/pvclock-abi.h > > diff --git a/arch/arm64/include/asm/pvclock-abi.h b/arch/arm64/include/asm/pvclock-abi.h > new file mode 100644 > index 000000000000..1f7cdc102691 > --- /dev/null > +++ b/arch/arm64/include/asm/pvclock-abi.h > @@ -0,0 +1,20 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* Copyright (C) 2019 Arm Ltd. */ > + > +#ifndef __ASM_PVCLOCK_ABI_H > +#define __ASM_PVCLOCK_ABI_H > + > +/* The below structures and constants are defined in ARM DEN0057A */ > + > +struct pvclock_vcpu_stolen_time_info { > + __le32 revision; > + __le32 attributes; > + __le64 stolen_time; > + /* Structure must be 64 byte aligned, pad to that size */ > + u8 padding[48]; > +} __packed; > + > +#define PV_VM_TIME_NOT_SUPPORTED -1 Isn't the intent for this to be the same value as SMCCC_RET_NOT_SUPPORTED? > +#define PV_VM_TIME_INVALID_PARAMETERS -2 It overlaps with SMCCC_RET_NOT_REQUIRED. Is that a problem? Should we consider a spec change for this? > + > +#endif > diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h > index 080012a6f025..e7f129f26ebd 100644 > --- a/include/linux/arm-smccc.h > +++ b/include/linux/arm-smccc.h > @@ -45,6 +45,7 @@ > #define ARM_SMCCC_OWNER_SIP 2 > #define ARM_SMCCC_OWNER_OEM 3 > #define ARM_SMCCC_OWNER_STANDARD 4 > +#define ARM_SMCCC_OWNER_STANDARD_HYP 5 > #define ARM_SMCCC_OWNER_TRUSTED_APP 48 > #define ARM_SMCCC_OWNER_TRUSTED_APP_END 49 > #define ARM_SMCCC_OWNER_TRUSTED_OS 50 > @@ -302,5 +303,18 @@ asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1, > #define SMCCC_RET_NOT_SUPPORTED -1 > #define SMCCC_RET_NOT_REQUIRED -2 > > +/* Paravirtualised time calls (defined by ARM DEN0057A) */ > +#define ARM_SMCCC_HV_PV_FEATURES \ > + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ > + ARM_SMCCC_SMC_64, \ > + ARM_SMCCC_OWNER_STANDARD_HYP, \ > + 0x20) > + > +#define ARM_SMCCC_HV_PV_TIME_ST \ > + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ > + ARM_SMCCC_SMC_64, \ > + ARM_SMCCC_OWNER_STANDARD_HYP, \ > + 0x22) > + > #endif /*__ASSEMBLY__*/ > #endif /*__LINUX_ARM_SMCCC_H*/ > diff --git a/virt/kvm/arm/hypercalls.c b/virt/kvm/arm/hypercalls.c > index f875241bd030..2906b2df99df 100644 > --- a/virt/kvm/arm/hypercalls.c > +++ b/virt/kvm/arm/hypercalls.c > @@ -5,6 +5,7 @@ > #include > > #include > +#include > > #include > #include > @@ -48,6 +49,14 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) > break; > } > break; > + case ARM_SMCCC_HV_PV_FEATURES: > + val = SMCCC_RET_SUCCESS; > + break; > + } > + break; > + case ARM_SMCCC_HV_PV_FEATURES: > + feature = smccc_get_arg1(vcpu); > + switch (feature) { > } > break; > default: Thanks, M. -- Without deviation from the norm, progress is not possible.