Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756411AbaDKJHk (ORCPT ); Fri, 11 Apr 2014 05:07:40 -0400 Received: from mail-qa0-f50.google.com ([209.85.216.50]:48103 "EHLO mail-qa0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755976AbaDKJHg (ORCPT ); Fri, 11 Apr 2014 05:07:36 -0400 MIME-Version: 1.0 In-Reply-To: References: <1397072736-10793-1-git-send-email-matthias.bgg@gmail.com> <1397072736-10793-2-git-send-email-matthias.bgg@gmail.com> Date: Fri, 11 Apr 2014 11:07:35 +0200 Message-ID: Subject: Re: [PATCH 1/4] clocksource: Add support for the Mediatek SoCs From: Matthias Brugger To: Olof Johansson Cc: "linux-kernel@vger.kernel.org" , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Randy Dunlap , Russell King - ARM Linux , Daniel Lezcano , Thomas Gleixner , Thierry Reding , Florian Vaussard , Jonathan Cameron , Jason Cooper , Andrew Lunn , Silvio F , =?UTF-8?Q?Heiko_St=C3=BCbner?= , Sebastian Hesselbarth , "devicetree@vger.kernel.org" , "linux-doc@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2014-04-09 23:52 GMT+02:00 Olof Johansson : > Hi, > > On Wed, Apr 9, 2014 at 12:45 PM, Matthias Brugger > wrote: >> This patch adds a clock source and clock event for the timer found >> on the Mediatek SoCs. >> >> The Mediatek General Porpose Timer block provides five 32 bit timers and >> one 64 bit timer. >> >> Two 32 bit timers are used: >> TIMER1: clock events supporting periodic and oneshot events >> TIMER2: clock source configured as a free running counter >> >> The General Porpose Timer block can be run with two clocks. A 13 MHz system >> clock and the RTC clock running at 32 KHz. This implementation uses the system >> clock. > > Hm, are you planning on using these on the Cortex-A7-based and newer > SoCs? On those, the arm generic timers should be available, and you > might be better off just using those there. I'm a bit puzzled about the timer naming. Are the arm generic timers the one used by ARM_ARCH_TIMER, or are they different ones? > > Of course, you'll still need these for the A9-based platforms, so the > driver might very well be needed anyway. Some of the earlier patches > seem to be for A7-based systems so I'm not sure what you're primarily > working on here. :) I'm working on a Cortex-A7 based platform. But ARM_ARCH_TIMER seems to get no clocking. Initializing the timer fails with: Architected timer frequency not available That's why I use the SoC timer. > > > -Olof -- motzblog.wordpress.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/