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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 F40FDC43441 for ; Wed, 21 Nov 2018 08:10:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B988C2146F for ; Wed, 21 Nov 2018 08:10:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B988C2146F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728499AbeKUSo1 (ORCPT ); Wed, 21 Nov 2018 13:44:27 -0500 Received: from mail-vs1-f68.google.com ([209.85.217.68]:36645 "EHLO mail-vs1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726195AbeKUSo1 (ORCPT ); Wed, 21 Nov 2018 13:44:27 -0500 Received: by mail-vs1-f68.google.com with SMTP id v205so2732178vsc.3 for ; Wed, 21 Nov 2018 00:10:56 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=oZOcTZjPYZsnpOdOWnXFo0vtIXWLgf7MyMaLFbnoQPw=; b=gfVupAC6n3vOGP2es/Thd69hoEJxWzFcCvn24EfnXCuIgROKS/+eOBvAyN7h2LlCr2 STKAtUzczIjHlXA9XRxM49IRgVvBXTE7UZ4fLOUtYWPfejixlFrrUN2ZV1D/sxT8X3GU FjlUNirhoYrnUIGNbmi+t7BZl4wqBO6kUA9DZII9S0ytGb7MwnyNewYNzK9D05KMVVvd 45T3kTILKEkChDb9b4sfxw68aTuH9nQjLRGPhPYX68HblaoMeYw6lHM4GdB2bQKcUI7h QQNK59iZuANcbTBdOnTT7jcAwr2Uc95ESdePsQjvifIqCEDWUq7J20bqJHc1jXSqEaU9 Y3XA== X-Gm-Message-State: AGRZ1gLDSQkLM7gzh96qr9ykXkinaySkGot7bCOzxJYurUf1DB+6T0ME HHoVBW4N3CRRcFV3DGjMfImEVEFPjhCrMe8lkioG+A== X-Google-Smtp-Source: AJdET5cgkz8XbeSq8MV+hP/ukkEdI/fA6fpfMoRSYw3Tce3SQgnlZi9p268CFHJYu5qsQ49/7yGZ/KaODrY6Kd2784E= X-Received: by 2002:a67:b60d:: with SMTP id d13mr2387135vsm.152.1542787856198; Wed, 21 Nov 2018 00:10:56 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: Geert Uytterhoeven Date: Wed, 21 Nov 2018 09:10:44 +0100 Message-ID: Subject: Re: [RFC PATCH v2 09/14] m68k: hp300: Remove hp300_gettimeoffset() To: Finn Thain Cc: Kars de Jong , Philip Blundell , Andreas Schwab , Arnd Bergmann , Stephen N Chivers , Thomas Gleixner , Daniel Lezcano , Michael Schmitz , John Stultz , Linus Walleij , linux-m68k , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Finn, On Wed, Nov 21, 2018 at 12:13 AM Finn Thain wrote: > On atari, the 68901 counts down to 0x01 and raises an interrupt. On mac, > the 6522 counts down to 0xFFFF then raises an interrupt. No idea about > amiga (Geert?) -- this has to be handled correctly to get a monotonic > clocksource. I'll fix this in v3 (where the information is available). The docs state that the CIA generates on interrupt on underflow, so I guess that's the same behavior as the 6522 VIA. Unfortunately the 24-bit ("TOD") counters in the two CIAs run from HSYNC resp. VSYNC, which depends on the video mode, and thus can't be used as a monotonic clock source. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds