From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Lezcano Subject: Re: [PATCH v2 2/2] clocksource/drivers/mtk_systimer: Add support for Mediatek SoCs Date: Wed, 27 Jun 2018 11:59:55 +0200 Message-ID: References: <1530086039-3763-1-git-send-email-stanley.chu@mediatek.com> <1530086039-3763-3-git-send-email-stanley.chu@mediatek.com> <2a40ec95-7352-f0c4-b394-d7b689de98ec@linaro.org> <1530093016.17448.35.camel@mtkswgap22> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <1530093016.17448.35.camel@mtkswgap22> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Stanley Chu Cc: Matthias Brugger , Thomas Gleixner , Rob Herring , linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, devicetree@vger.kernel.org, wsd_upstream@mediatek.com List-Id: devicetree@vger.kernel.org On 27/06/2018 11:50, Stanley Chu wrote: > On Wed, 2018-06-27 at 11:39 +0200, Daniel Lezcano wrote: >> On 27/06/2018 09:53, Stanley Chu wrote: >>> This patch adds a new clock event for the timer >>> found on the Mediatek SoCs. >>> >>> The Mediatek System Timer has several 32-bit timers. >>> Only one timer is used by this driver as a clock event >>> supporting oneshot events. >>> >>> The System Timer 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 with no clock source divider. >> >> Recent platforms have the arch_arm_timer and it will be always selected. >> >> What is the benefit of adding this timer ? >> >> > Hi Daniel, > > To save power as much as possible, our platform enables > "arch_timer_c3stop" in arch_arm_timer, and thus another always-on timer > is required for tick-broadcasting. System Timer is introduced for above > purpose Obviously :) -- Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog