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=-5.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,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 9D888C2BB1D for ; Tue, 7 Apr 2020 09:46:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 69EE92074B for ; Tue, 7 Apr 2020 09:46:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="V9j7Nvrk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728113AbgDGJqh (ORCPT ); Tue, 7 Apr 2020 05:46:37 -0400 Received: from mail26.static.mailgun.info ([104.130.122.26]:18336 "EHLO mail26.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726725AbgDGJqg (ORCPT ); Tue, 7 Apr 2020 05:46:36 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1586252796; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=Ul3YhDd1rPscgFpO4CCJ18JVqPLmuQ5bBOiQ1R8owsk=; b=V9j7NvrkmWPKQd6ECIQqP6Xxc/2RryYtFG1ePOcuHNZLYkwuTRldCtKTQ3Xl9YXSUCiD4S4I G2/Bng8yf9b6aIPm78wqmYi/pdRSdsxBK5TFZKn2mokBSh5ZkEGgUVHy9DihsKow+nH6w6Z0 KIyvCj0lMHpcFY5hng3BMj0UaPc= X-Mailgun-Sending-Ip: 104.130.122.26 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by mxa.mailgun.org with ESMTP id 5e8c4bfb.7fc0072c6490-smtp-out-n03; Tue, 07 Apr 2020 09:46:35 -0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1001) id BB59AC44788; Tue, 7 Apr 2020 09:46:35 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: saiprakash.ranjan) by smtp.codeaurora.org (Postfix) with ESMTPSA id 38318C433F2; Tue, 7 Apr 2020 09:46:35 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Tue, 07 Apr 2020 15:16:35 +0530 From: Sai Prakash Ranjan To: Mike Leach Cc: Mathieu Poirier , Suzuki K Poulose , Leo Yan , Alexander Shishkin , Stephen Boyd , linux-arm-kernel , linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org Subject: Re: [RFC PATCH] coresight: dynamic-replicator: Fix handling of multiple connections In-Reply-To: References: <20200405102819.28460-1-saiprakash.ranjan@codeaurora.org> Message-ID: <6c0f45488f8a44bf860759e00fcabd09@codeaurora.org> X-Sender: saiprakash.ranjan@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Mike, Thanks for taking a look. On 2020-04-06 16:25, Mike Leach wrote: > Hi, > > The programmable replicator hardware by design enables trace through > both ports on reset. (see 1, section 4.4, 9.11) The replicator driver > overrides this functionality to disable output, until the Coresight > infrastructure chooses a path from source to sink. > Now given that the hardware design is such that we must be able to > allow trace to be sent to both ports, a generic patch to prevent this > does not seem appropriate here. > > I think this needs further investigation - to determine why this > appears to be failing in this particular instance. > Yes, this probably needs further investigation, but CPU hardlock stack trace doesnt help much. I could always trigger this hard lockup without this patch on SC7180 SoC and this is only seen when ETR is used as the sink. The only difference I could see between non working case (on SC7180 [1]) and the working case (on SDM845 [2]) is the path from source to sink. SC7180 source to sink path(Not working): ---------------------------------------- etm0_out | apss_funnel_in0 | apss_merge_funnel_in | funnel1_in4 | merge_funnel_in1 | swao_funnel_in | etf_in | swao_replicator_in | replicator_in | etr_in SDM845 source to sink path(Working): ------------------------------------ etm0_out | apss_funnel_in0 | apss_merge_funnel_in | funnel2_in5 | merge_funnel_in2 | etf_in | replicator_in | etr_in [1] - https://lore.kernel.org/patchwork/patch/1212946/ [2] - https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom/sdm845.dtsi?h=v5.6#n1910 Thanks, Sai -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation