From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423012AbdKQWt7 (ORCPT ); Fri, 17 Nov 2017 17:49:59 -0500 Received: from Galois.linutronix.de ([146.0.238.70]:53027 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422995AbdKQWtr (ORCPT ); Fri, 17 Nov 2017 17:49:47 -0500 Date: Fri, 17 Nov 2017 23:49:41 +0100 (CET) From: Thomas Gleixner To: Jan Kiszka cc: Ingo Molnar , "H . Peter Anvin" , x86@kernel.org, Linux Kernel Mailing List , jailhouse-dev@googlegroups.com Subject: Re: [PATCH 05/10] x86: jailhouse: Set up timekeeping In-Reply-To: <62f3fde8db44e5aedf934b5a753d448979f50082.1510817211.git.jan.kiszka@siemens.com> Message-ID: References: <62f3fde8db44e5aedf934b5a753d448979f50082.1510817211.git.jan.kiszka@siemens.com> User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 16 Nov 2017, Jan Kiszka wrote: > Calibrate the TSC and, where necessary, the APIC timer against the > TMTIMER. We need our own implementation as neither the PIC nor the HPET > are available, and the standard calibration routines try to make use of > them. Why is this needed at all? The host the frequency already. So this can be done w/o pmtimer and extra calibration routine. Thanks, tglx