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 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 9636AC43381 for ; Mon, 4 Mar 2019 17:29:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B4142070B for ; Mon, 4 Mar 2019 17:29:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727266AbfCDR30 (ORCPT ); Mon, 4 Mar 2019 12:29:26 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:36430 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725974AbfCDR30 (ORCPT ); Mon, 4 Mar 2019 12:29:26 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8CFA6A78; Mon, 4 Mar 2019 09:29:25 -0800 (PST) Received: from [10.1.196.93] (en101.cambridge.arm.com [10.1.196.93]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 988703F703; Mon, 4 Mar 2019 09:29:23 -0800 (PST) Subject: Re: [PATCH v2] dts: arm64: add CoreSight trace support for hi3660 To: mathieu.poirier@linaro.org, leo.yan@linaro.org Cc: shiwanglai@hisilicon.com, robh+dt@kernel.org, mark.rutland@arm.com, john.stultz@linaro.org, xuwei5@huawei.com, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, coresight@lists.linaro.org, suzhuangluan@hisilicon.com References: <6496F4728C09F6479CFF21A8E67D33D568F32660@dggema525-mbx.china.huawei.com> <20190302125955.GA11385@leoy-ThinkPad-X240s> From: Suzuki K Poulose Message-ID: <9109e498-0cd9-0b81-15a0-2208d4282359@arm.com> Date: Mon, 4 Mar 2019 17:29:22 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 04/03/2019 17:18, Mathieu Poirier wrote: > On Sat, 2 Mar 2019 at 06:00, Leo Yan wrote: >> >> On Sat, Mar 02, 2019 at 09:45:22AM +0000, Shiwanglai wrote: >> >> [...] >> >>>> + /* Top internals */ >>>> + funnel@ec031000 { >>>> + compatible = "arm,coresight-funnel", "arm,primecell"; >>>> + reg = <0 0xec031000 0 0x1000>; >>>> + clocks = <&crg_ctrl HI3660_PCLK>; >>>> + clock-names = "apb_pclk"; >>>> + >>>> + out-ports { >>>> + port { >>>> + top_funnel_out: endpoint { >>>> + remote-endpoint = >>>> + <&top_etf_in>; >>>> + }; >>>> + }; >>>> + }; >>>> + >>>> + in-ports { >>>> + #address-cells = <1>; >>>> + #size-cells = <0>; >>>> + >>>> + port@0 { >>>> + reg = <0>; >>>> + top_funnel_in0: endpoint { >>>> + remote-endpoint = >>>> + <&cluster0_etf_out>; >>>> + }; >>>> + }; >>>> + >>>> + port@1 { >>>> + reg = <0>; >>> >>> Here should s/<0>/<1>; otherwise DTC will complain warning for mismatching between 'port@1' and 'reg = <0>'. >> >>> -- if reg set to 1, then there's no data output from cluster 1 to top. >> >> Thanks for the info, Wanglai. Now I see why write as it is. >> >> I can confirm if directly use your patch with perf with mainline >> kernel I can capture CoreSight trace data successfully on Hikey960 >> board. >> >> But since this DT binding will introduce DTC warning, I personally >> think we can improve for this with below method: >> >> We can create a funnel node named "funnel_combo", and we don't need to >> specify register address range for it; and cluster 0 and cluster 1 will >> output to "funnel_combo" and "funnel_combo" will output to the top >> funnel. Thus the DT binding will write as below. >> >> To support for a funnel without any register address range (we have >> support replicator like this mode), we also need to extend the driver >> drivers/hwtracing/coresight/coresight-funnel.c. >> >> Mathieu, Mike, Suzuki, could you help confirm this is the right >> direction we should move forward to? > > Leo, thanks for testing this out. Shiwanglai, please add Suzuki and > myself to future revision of this set - this will help you getting a > timely response for your work. > > As Leo pointed out we already have support for replicators that don't > have a register map and the same thing should be done in this case. > But contrary to what was done for replicators, I think we should keep > the drivers in the same file as Russell did here[1]. That way we can > keep all things funnel at the same place and reduce the amount of > kernel configuration options. I back that. I have already merged the static and programmable replicators into one and this should be out here soon. So, I back the single driver approach for funnels. Cheers Suzuki > > Regards, > Mathieu > > [1]. https://elixir.bootlin.com/linux/latest/source/drivers/tty/serial/amba-pl011.c#L2819 > >>