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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,UNPARSEABLE_RELAY 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 3CE29C43142 for ; Tue, 26 Jun 2018 08:03:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E1F7E25FEB for ; Tue, 26 Jun 2018 08:03:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E1F7E25FEB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=mediatek.com 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 S1752695AbeFZIDr (ORCPT ); Tue, 26 Jun 2018 04:03:47 -0400 Received: from mailgw01.mediatek.com ([210.61.82.183]:55127 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1752169AbeFZIDp (ORCPT ); Tue, 26 Jun 2018 04:03:45 -0400 X-UUID: c5f6c9f62a104778841a2ebfc228662f-20180626 Received: from mtkcas09.mediatek.inc [(172.21.101.178)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 799738630; Tue, 26 Jun 2018 16:03:40 +0800 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs03n2.mediatek.inc (172.21.101.182) with Microsoft SMTP Server (TLS) id 15.0.1210.3; Tue, 26 Jun 2018 16:03:38 +0800 Received: from [172.21.77.33] (172.21.77.33) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1210.3 via Frontend Transport; Tue, 26 Jun 2018 16:03:38 +0800 Message-ID: <1530000218.17448.28.camel@mtkswgap22> Subject: Re: Add system timer driver for Mediatek SoCs From: Stanley Chu To: Daniel Lezcano CC: Matthias Brugger , Thomas Gleixner , Rob Herring , , , , Date: Tue, 26 Jun 2018 16:03:38 +0800 In-Reply-To: <561c2c41-ea92-3ad8-a1d7-aeef46cdc601@linaro.org> References: <1529910601-15005-1-git-send-email-stanley.chu@mediatek.com> <1529917631.17448.22.camel@mtkswgap22> <561c2c41-ea92-3ad8-a1d7-aeef46cdc601@linaro.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit MIME-Version: 1.0 X-MTK: N Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2018-06-26 at 09:31 +0200, Daniel Lezcano wrote: > On 25/06/2018 11:07, Stanley Chu wrote: > > On Mon, 2018-06-25 at 09:34 +0200, Daniel Lezcano wrote: > >> On 25/06/2018 09:09, Stanley Chu wrote: > >>> This patch adds a new driver for system timer on the Mediatek SoCs. > >> > >> Please elaborate why we need yet another timer. > >> > >> Is this timer present on all Mediatek platform ? Does it always co-exist > >> with the existing one ? > >> > >> > >> > >> > > Hi Daniel, > > > > This new "system timer" only exists on recent Mediatek platforms, > > for example, MT6765. We will upstream driver first, and then update > > device tree on MT6765 later. > > > > System timer is designed and optimized as a SoC timer for > > tick-broadcasting. Besides timer IP has simpler register manipulation > > and friendly low-power design. > > > > There is no plan to remove existed "General Purpose Timer" now. > > It is unclear what "General Purpose Timer" and "System Timer" differ > except they are different timers running on different platforms. > > Merge them into a single timer-mediatek.c file. > Hi Daniel, Yes, they are different timers running on different platforms. "System Timer" can replace "General Purpose Timer" in recent platforms, for example, MT6765. Thanks. Stanley Chu