From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932427AbcDVRTg (ORCPT ); Fri, 22 Apr 2016 13:19:36 -0400 Received: from mailapp01.imgtec.com ([195.59.15.196]:29198 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932298AbcDVRTc (ORCPT ); Fri, 22 Apr 2016 13:19:32 -0400 From: James Hogan To: Ralf Baechle CC: James Hogan , Daniel Lezcano , Thomas Gleixner , , Subject: [PATCH 0/4] MIPS: Guest timekeeping improvements Date: Fri, 22 Apr 2016 18:19:13 +0100 Message-ID: <1461345557-2763-1-git-send-email-james.hogan@imgtec.com> X-Mailer: git-send-email 2.4.10 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [192.168.154.110] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org These patches improve timekeeping of MIPS/Malta kernels running in a KVM guest. Patch 2 fixes malta frequency calculation under virtualisation, especially on very slow targets (FPGA / emulators). Patch 1 is a minor fix for something I noticed while writing patch 2. Patch 3 drops the use of the PIT timer for Malta, which is slow to emulate with KVM + QEMU. Finally patch 4 calculates min_delta_ns of cevt-r4k dynamically to handle virtualised environments with software emulated Count/Compare, and where Count frequency may not be directly related to actual CPU speed (and so the static value of 0x300 may be no good). James Hogan (4): MIPS: malta-time: Start GIC count before syncing to RTC MIPS: malta-time: Take seconds into account MIPS: malta-time: Don't use PIT timer for cevt/csrc MIPS: cevt-r4k: Dynamically calculate min_delta_ns arch/mips/Kconfig | 1 - arch/mips/kernel/cevt-r4k.c | 82 +++++++++++++++++++++++++++++++++++++++- arch/mips/mti-malta/malta-time.c | 50 +++++++++++++++--------- 3 files changed, 113 insertions(+), 20 deletions(-) Cc: Ralf Baechle Cc: Daniel Lezcano Cc: Thomas Gleixner Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org -- 2.4.10