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=-11.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_SANE_1 autolearn=unavailable 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 79611C433E2 for ; Fri, 17 Jul 2020 14:40:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5B092208DB for ; Fri, 17 Jul 2020 14:40:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727029AbgGQOkT (ORCPT ); Fri, 17 Jul 2020 10:40:19 -0400 Received: from out28-149.mail.aliyun.com ([115.124.28.149]:40932 "EHLO out28-149.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726198AbgGQOkT (ORCPT ); Fri, 17 Jul 2020 10:40:19 -0400 X-Alimail-AntiSpam: AC=CONTINUE;BC=0.07445006|-1;CH=green;DM=|CONTINUE|false|;DS=CONTINUE|ham_regular_dialog|0.0713628-0.00445208-0.924185;FP=0|0|0|0|0|-1|-1|-1;HT=e02c03301;MF=zhouyanjie@wanyeetech.com;NM=1;PH=DS;RN=12;RT=12;SR=0;TI=SMTPD_---.I3R317z_1594996812; Received: from 192.168.10.205(mailfrom:zhouyanjie@wanyeetech.com fp:SMTPD_---.I3R317z_1594996812) by smtp.aliyun-inc.com(10.147.41.121); Fri, 17 Jul 2020 22:40:13 +0800 Subject: Re: [PATCH v6 2/2] clocksource: Ingenic: Add support for the Ingenic X1000 OST. To: Daniel Lezcano , linux-kernel@vger.kernel.org Cc: devicetree@vger.kernel.org, robh+dt@kernel.org, tglx@linutronix.de, paul@crapouillou.net, dongsheng.qiu@ingenic.com, aric.pzqi@ingenic.com, rick.tyliu@ingenic.com, yanfei.li@ingenic.com, sernia.zhou@foxmail.com, zhenwenjin@gmail.com References: <20200710170259.29028-1-zhouyanjie@wanyeetech.com> <20200710170259.29028-3-zhouyanjie@wanyeetech.com> <9c64bc35-c043-6e4b-cfc3-50f19e4cb315@linaro.org> From: Zhou Yanjie Message-ID: <77c49585-63c2-7784-83cc-bf6151095b69@wanyeetech.com> Date: Fri, 17 Jul 2020 22:40:09 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.3.0 MIME-Version: 1.0 In-Reply-To: <9c64bc35-c043-6e4b-cfc3-50f19e4cb315@linaro.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Daniel, 在 2020/7/17 下午4:02, Daniel Lezcano 写道: > On 17/07/2020 08:13, Zhou Yanjie wrote: >> Hi Daniel, >> >> 在 2020/7/17 下午12:20, Daniel Lezcano 写道: >>> On 10/07/2020 19:02, 周琰杰 (Zhou Yanjie) wrote: >>>> X1000 and SoCs after X1000 (such as X1500 and X1830) had a separate >>>> OST, it no longer belongs to TCU. This driver will register both a >>>> clocksource and a sched_clock to the system. >>>> >>>> Tested-by: 周正 (Zhou Zheng) >>>> Co-developed-by: 漆鹏振 (Qi Pengzhen) >>>> Signed-off-by: 漆鹏振 (Qi Pengzhen) >>>> Signed-off-by: 周琰杰 (Zhou Yanjie) >>>> Reviewed-by: Paul Cercueil >>>> --- >>>> >>>> Notes: >>>>      v1->v2: >>>>      Fix compile warnings. >>>>      Reported-by: kernel test robot >>>>           v2->v3: >>>>      No change. >>>>           v3->v4: >>>>      1.Rename "ost" to "sysost" >>>>      1.Remove unrelated changes. >>>>      2.Remove ost_clock_parent enum. >>>>      3.Remove ost->percpu_timer_channel/ost->global_timer_channel. >>>>      4.Set up independent .recalc_rate/.set_rate for percpu/global >>>> timer. >>>>      5.No longer call functions in variable declarations. >>>>           v4->v5: >>>>      Use "of_io_request_and_map()" instead "of_iomap()". >>>>      Suggested-by: Paul Cercueil >>>>           v5->v6: >>>>      No change. >>>> >>>>   drivers/clocksource/Kconfig          |  11 + >>>>   drivers/clocksource/Makefile         |   1 + >>>>   drivers/clocksource/ingenic-sysost.c | 539 >>>> +++++++++++++++++++++++++++++++++++ >>>>   3 files changed, 551 insertions(+) >>>>   create mode 100644 drivers/clocksource/ingenic-sysost.c >>>> >>>> diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig >>>> index 91418381fcd4..1bca8b8fb30f 100644 >>>> --- a/drivers/clocksource/Kconfig >>>> +++ b/drivers/clocksource/Kconfig >>>> @@ -696,6 +696,17 @@ config INGENIC_TIMER >>>>       help >>>>         Support for the timer/counter unit of the Ingenic JZ SoCs. >>>>   +config INGENIC_SYSOST >>>> +    bool "Clocksource/timer using the SYSOST in Ingenic X SoCs" >>> We usually use silent options and let the platform's Kconfig enable it. >>> We show up the option only when COMPILE_TEST is enabled. >>> >>> Is there a reason to do it differently? >> >> Do you mean >> >> bool "Clocksource/timer using the SYSOST in Ingenic X SoCs" >> >> or >> >> default MACH_INGENIC ? > Both, no default here. > > eg. > > bool "Clocksource/timer using the SYSOST in Ingenic X SoCs" if COMPILE_TEST > > and > > in arch/mips/Kconfig in the config MACH_INGENIC section : > > ... > select INGENIC_SYSOST > ... Sure, I will do it in the next version. Thanks and best regards! >> This driver has some origins from "INGENIC_TIMER" driver and >> "INGENIC_OST" driver. >> Early Ingenic processors used TCU (timer/counter unit, has 6 or 8 >> generic timer channels) to provide clocksource and clockevent (both with >> only 16bit precision). This part of the processor can only use >> "INGENIC_TIMER" driver. >> >> Later processors provide an independent 32bit or 64bit timer channel >> (still under TCU, known as ost channel, this channel can not generate >> interrupt) to provid higher precision clocksource. The "INGENIC_OST" >> driver is for this channel. These processors can use "INGENIC_TIMER" >> driver, but using "INGENIC_OST" driver to provide higher precision >> clocksource would be a better choice (clockevent still needs to be >> provided by generic timer channel of TCU, and still 16bit precision). >> >> And the recent processors provide a SYSOST components, it is independent >> from TCU, including a 64bit timer channel for clocksource and a 32bit >> timer channel for clockevent. Although these processors can also use >> "INGENIC_TIMER" driver, but the better choice is completely independent >> use of "INGENIC_SYSOST" driver to provide higher precision clocksource >> and clockevent. > Ok, the rating should do the job then. > > Thanks for the explanation. > >> You may have already noticed that this independent SYSOST component is >> like an upgraded and streamlined TCU, which only retains one generic >> timer channel that can generate interrupts, upgrade it from 16bit to >> 32bit, and then retain the 64bit ost channel. so the driver code and >> Kconfig code of this patch is largely referenced >> "INGENIC_TIMER" driver and "INGENIC_OST" driver. >> >> Thanks and best regards! >> >>>> +    default MACH_INGENIC >>>> +    depends on MIPS || COMPILE_TEST >>>> +    depends on COMMON_CLK >>>> +    select MFD_SYSCON >>>> +    select TIMER_OF >>>> +    select IRQ_DOMAIN >>>> +    help >>>> +      Support for the SYSOST of the Ingenic X Series SoCs. >>>> + >>> [ ... ] >>> >>> >