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 X-Spam-Level: X-Spam-Status: No, score=-14.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6B0FC2D0E4 for ; Mon, 23 Nov 2020 12:00:35 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 167572076E for ; Mon, 23 Nov 2020 12:00:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="yYaaYHKL"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="HQQpseAI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 167572076E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:Message-ID:References:In-Reply-To:Subject:To:From: Date:MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=j6GEkWLnulN2z7KUCo0k8AGpZzyeyXBnlCsDkVLJYrE=; b=yYaaYHKLFNO30J/yk9a73oqjU sidcCKTuW/lCnBuema+T52WfYWbbWnlzXZ8RNlxSqQT5y10WUkj/3O8tMhRNETDwRnAxDLHJFprKZ zUseFJvBiOmcE4RWD/T7HIJ/uIRAPrCVwl+BnfLhzDE5D0/aE49SIrE6OiIsd8G2zVhXPKlqONC04 QTLvOY32BsQY4cjDTBQx1nS0MSlUXuXnbxlBwFGdF8JlTvjTMlsKqfa8WMPpbn5DQb6bOG0uVnX/A OWU5uvYl7xxiAxkXEIa4oTWMxu5YX5UIR+8AfzRHpm+sANqJoNFOModsH9Q5i0Cso/pJFShOEsBCT FWs/zWehg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1khAV2-0005Y5-Qn; Mon, 23 Nov 2020 11:59:16 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1khAUz-0005XO-LC for linux-arm-kernel@lists.infradead.org; Mon, 23 Nov 2020 11:59:15 +0000 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 368802076E; Mon, 23 Nov 2020 11:59:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1606132752; bh=SNzmc2sgfjK6RMMu/GL0rJxigW65dyO8WaugKYy1Ed4=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=HQQpseAIMOO0IZb4YiComOvdilzhwi7IJMFaJHJk7huXj7OGXw6ILYx117GWvUA13 /KeJ8/5AgMzifF6/kwnF4ABjF+D92ZqMB+gPby5nu1oYUfLLF18DPYlSbZmowyanA/ qETj81GnR39/kacyhwt/ZzX7XQeUcwXitxywMDIU= Received: from disco-boy.misterjones.org ([51.254.78.96] helo=www.loen.fr) by disco-boy.misterjones.org with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94) (envelope-from ) id 1khAUw-00Cu3B-03; Mon, 23 Nov 2020 11:59:10 +0000 MIME-Version: 1.0 Date: Mon, 23 Nov 2020 11:59:09 +0000 From: Marc Zyngier To: Jianyong Wu Subject: Re: [PATCH v15 6/9] arm64/kvm: Add hypercall service for kvm ptp. In-Reply-To: References: <20201111062211.33144-1-jianyong.wu@arm.com> <20201111062211.33144-7-jianyong.wu@arm.com> User-Agent: Roundcube Webmail/1.4.9 Message-ID: <276428d3d291f703e2f0c2c323194e98@kernel.org> X-Sender: maz@kernel.org X-SA-Exim-Connect-IP: 51.254.78.96 X-SA-Exim-Rcpt-To: jianyong.wu@arm.com, justin.he@arm.com, kvm@vger.kernel.org, netdev@vger.kernel.org, richardcochran@gmail.com, linux-kernel@vger.kernel.org, sean.j.christopherson@intel.com, steven.price@arm.com, Andre.Przywara@arm.com, john.stultz@linaro.org, yangbo.lu@nxp.com, pbonzini@redhat.com, tglx@linutronix.de, nd@arm.com, will@kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201123_065914_195464_D69C8BC2 X-CRM114-Status: GOOD ( 17.74 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: justin.he@arm.com, kvm@vger.kernel.org, netdev@vger.kernel.org, richardcochran@gmail.com, yangbo.lu@nxp.com, linux-kernel@vger.kernel.org, sean.j.christopherson@intel.com, steven.price@arm.com, john.stultz@linaro.org, Andre.Przywara@arm.com, pbonzini@redhat.com, tglx@linutronix.de, nd@arm.com, will@kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2020-11-23 10:44, Marc Zyngier wrote: > On 2020-11-11 06:22, Jianyong Wu wrote: >> ptp_kvm will get this service through SMCC call. >> The service offers wall time and cycle count of host to guest. >> The caller must specify whether they want the host cycle count >> or the difference between host cycle count and cntvoff. >> >> Signed-off-by: Jianyong Wu >> --- >> arch/arm64/kvm/hypercalls.c | 61 >> +++++++++++++++++++++++++++++++++++++ >> include/linux/arm-smccc.h | 17 +++++++++++ >> 2 files changed, 78 insertions(+) >> >> diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c >> index b9d8607083eb..f7d189563f3d 100644 >> --- a/arch/arm64/kvm/hypercalls.c >> +++ b/arch/arm64/kvm/hypercalls.c >> @@ -9,6 +9,51 @@ >> #include >> #include >> >> +static void kvm_ptp_get_time(struct kvm_vcpu *vcpu, u64 *val) >> +{ >> + struct system_time_snapshot systime_snapshot; >> + u64 cycles = ~0UL; >> + u32 feature; >> + >> + /* >> + * system time and counter value must captured in the same >> + * time to keep consistency and precision. >> + */ >> + ktime_get_snapshot(&systime_snapshot); >> + >> + // binding ptp_kvm clocksource to arm_arch_counter >> + if (systime_snapshot.cs_id != CSID_ARM_ARCH_COUNTER) >> + return; >> + >> + val[0] = upper_32_bits(systime_snapshot.real); >> + val[1] = lower_32_bits(systime_snapshot.real); > > What is the endianness of these values? I can't see it defined > anywhere, and this is likely not to work if guest and hypervisor > don't align. Scratch that. This is all passed via registers, so the endianness of the data is irrelevant. Please discard any comment about endianness I made in this review. The documentation aspect still requires to be beefed up. Thanks, M. -- Jazz is not dead. It just smells funny... _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel