From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 055C2606A321 for ; Wed, 11 Nov 2026 20:43:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=QtlpQXN5; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=nwawK37F DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Unsubscribe-Post:List-Owner; bh=YkiuKwTzFaKxocYqHbZJaiH6LJSy5oJp9dJAcEhaIF0=; b=QtlpQXN5UdKL1iHBzlzVBr0hN/ 1e3H53Vb6FecC14Zxm3JUNhuGfyYSuOLSkQDTxE65GlCJIqgoz1Y40YLE6+viER+1K56qn7d58Ukt Fquyd2EK2bupy/mFc0hc0jKvZIWOTYMFq+iJETQ4LZy+1zsT+tW105kxw5mV/TIJT3peqzlc1W6km VeUZJpcMOvI+Hd+DNbc2R0Ws2MFubzkAKWbdvmzS81tjZ/GYdMOGCf3jxHvSi8haG6wiF5i5NO+KG pJTJJ637BnjSr2tApW/GwkuXSBIGq48men8YigpynIGYaRH+enZBTqymPQOnWFLkajrZxpMN8eJrg FBXb70+g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xRFAI-00000007fgK-0Gcq; Wed, 11 Nov 2026 20:43:30 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xRFAE-00000007fe8-2q1k for linux-arm-kernel@lists.infradead.org; Wed, 11 Nov 2026 20:43:28 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 41A64153B; Wed, 11 Nov 2026 12:43:22 -0800 (PST) Received: from localhost (unknown [10.2.196.114]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D12223F85F; Wed, 11 Nov 2026 12:43:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1794429805; bh=mx3VbQ9/b7aZO8Gcx1adUQM+AmPwFj6BLz1d9u/uU8U=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nwawK37Fkk3B1Dd8xpjDH02kguU+B9x/ZRaD5YNvyMo74wCWalB0GpoJEeLPKJE86 31HnfzhNse3dMDQrgcPdcaEiu7fOuN33UNqHb/5GPmekgyGPYeGmqNaT+5QEIdipZn FwgeBshyJewJ+AFuAZMFCFOSPHuewTnmyAlPLNyA= Date: Wed, 11 Nov 2026 20:43:22 +0000 From: Leo Yan To: Rob Herring Cc: Jie Gan , Suzuki K Poulose , Mike Leach , James Clark , Krzysztof Kozlowski , Conor Dooley , Tingwei Zhang , Yuanfang Zhang , Alexander Shishkin , Bjorn Andersson , Konrad Dybcio , Abel Vesa , Jingyi Wang , linux-arm-msm@vger.kernel.org, coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Konrad Dybcio , Krzysztof Kozlowski Subject: Re: [PATCH v7 0/5] Fix traceNoC probe issue on multiple QCOM platforms Message-ID: <20261111204322.GH9176@e132581.arm.com> References: <20261110-fix-trace-noc-probe-issue-v7-0-2f06905c77fe@oss.qualcomm.com> <20261110154643.GA4159803-robh@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261110154643.GA4159803-robh@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261111_124327_100182_B4CA6D3A X-CRM114-Status: GOOD ( 14.26 ) X-Spam-Score: -4.4 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-5.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Tue, Nov 10, 2026 at 09:46:43AM -0600, Rob Herring wrote: > On Tue, Nov 10, 2026 at 09:21:13AM +0800, Jie Gan wrote: > > The CoreSight TNOC (Trace Network-On-Chip) binding so far only allowed the > > two-string AMBA form "qcom,coresight-tnoc", "arm,primecell". That form > > forces the device onto the AMBA bus, where the driver must read the > > peripheral ID from the device registers during probe. On several QCOM > > platforms this AMBA peripheral-ID probing fails, so the traceNoC device > > never probes and its trace path is unavailable. > > But it works fine on some platforms? We have a property to override the > peripheral-ID which would solve your issue. That would be much simpler > and avoid the ABI break on any of the working platforms. Looking back at the earlier discussion [1], Jie in v2 already proposed "arm,primecell-periphid". Questions about AMBA IDs and ATID handling got mixed together. The series later moved towards platform-device probing, then became current shape. Hope we make the right decision on arm,primecell-periphid this time. Anyway, I'd like to apologise to Jie for all the back and forth. Thanks, Leo [1] https://lore.kernel.org/linux-arm-kernel/9432df20-08bf-4134-b4b9-e6b5d618af81@oss.qualcomm.com/