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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 4CAA4C83000 for ; Wed, 29 Apr 2020 17:11:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 25958208FE for ; Wed, 29 Apr 2020 17:11:34 +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="CR1gUi1c" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726481AbgD2RLd (ORCPT ); Wed, 29 Apr 2020 13:11:33 -0400 Received: from mail26.static.mailgun.info ([104.130.122.26]:53209 "EHLO mail26.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726493AbgD2RLb (ORCPT ); Wed, 29 Apr 2020 13:11:31 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1588180290; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=2H/grRhp1qnjOIul3MbQSy7YNYNUS9RRvwG048+TsJY=; b=CR1gUi1c7us62lKiLzfeYgHzlpIWhmxLMrRBNznCQ5MfCmvW9226GSJcAoGt7i733adP5L6f dQfiwtst/5NmLKk3eaTtasVfPeuj3/Gnj/A/SwHuqC+XwlmuOQO+yOLLcSamqZSeBdD++0WD ZYbZSANFgsBKJZUn/26E1kcqBkU= X-Mailgun-Sending-Ip: 104.130.122.26 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== 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 5ea9b52c.7fea8db43ae8-smtp-out-n01; Wed, 29 Apr 2020 17:11:08 -0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 3EC70C432C2; Wed, 29 Apr 2020 17:11:07 +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 834D7C433D2; Wed, 29 Apr 2020 17:11:06 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Wed, 29 Apr 2020 22:41:06 +0530 From: Sai Prakash Ranjan To: Mike Leach Cc: Suzuki K Poulose , Mathieu Poirier , Stephen Boyd , Linux Kernel Mailing List , linux-arm-msm@vger.kernel.org, linux-arm-kernel Subject: Re: [PATCH] coresight: dynamic-replicator: Fix handling of multiple connections In-Reply-To: References: <20200426143725.18116-1-saiprakash.ranjan@codeaurora.org> <84918e7d-c933-3fa1-a61e-0615d4b3cf2c@arm.com> <668ea1283a6dd6b34e701972f6f71034@codeaurora.org> <5b0f5d77c4eec22d8048bb0ffa078345@codeaurora.org> <759d47de-2101-39cf-2f1c-cfefebebd548@arm.com> <7d343e96cf0701d91152fd14c2fdec42@codeaurora.org> Message-ID: X-Sender: saiprakash.ranjan@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Hi Mike, On 2020-04-29 22:28, Mike Leach wrote: > Hi, > [...] >> >> > You need to find what is resetting the IDFILTERs to 0 for replicator1. >> >> > >> >> >> >> That is right. >> >> >> > >> > By default all replicators have the IDFILTER registers set to 0 out of >> > hardware reset. This ensures that programmable replicators behave in >> > the same way as non-programmable replicators out of reset. >> > >> > The dynamic_replicator_reset() is of course a driver state reset - >> > which filters out all trace on the output ports. The trace is then >> > enabled when we set the trace path from source to sink. >> > >> >> Thanks for these explanations. >> >> > It seems to me that you have 2 problems that need solving here: >> > >> > 1) Why does the reset_replicator() called from probe() _not_ work >> > correctly on replicator 1? It seems to work later if you introduce a >> > reset after more of the system has powered and booted. This is >> > startiing to look a little like a PM / clocking issue. >> >> reset_replicator() does work in probe correctly for both replicators, >> below logs is collected before and after reset in probe. It is later >> that it's set back to 0x0 and hence the suggestion to look at firmware >> using this replicator1. >> > OK - sorry I read your statement saying that replicator1 was 0 after > the reset in probe(), rather than look at the logs. > > From the logs it is working at the time probe() occurs, but by the > time we come to enable the replicator later, something has reset these > registers / hardware outside the control of the replicator driver. > Yes, I will try to get some more information from the firmware side if there is anything messing up. > >> [ 8.477669] func replicator_probe before reset replicator >> replicator1 >> REPLICATOR_IDFILTER0=0x0 REPLICATOR_IDFILTER1=0x0 >> [ 8.489470] func replicator_probe after reset replicator >> replicator1 >> REPLICATOR_IDFILTER0=0xff REPLICATOR_IDFILTER1=0xff >> >> > >> > This failure is causing the state when we are trying to set an output >> > port that both branches of this replicator are enabled for output. >> > In effect for this replicator, setting the output port has no effect >> > as it is already enabled. >> > >> > 2) Why does having both ports of this repilicator enabled cause a hard >> > lockup? This is a separate hardware / system issue. >> > >> > The worst that should happen if both branches of a replicator are >> > enabled is that you get undesirable back pressure. (e.g. there is a >> > system we have seen - I think it is Juno - where there is a static >> > replicator feeding the TPIU and ETR - we need to disable the TPIU to >> > prevent undesired back pressure). >> > >> >> Ok so hardlockup is not expected because of this backpressure. >> > > Hardlockup is not expected, but this is not related to any possible > backpressure. > > Ordinarily having both legs of a replicator enabled should not cause > system failure. > Ok got it, thanks. Thanks, Sai -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation