From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 361DF1EA65; Fri, 26 Jun 2026 15:49:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782488994; cv=none; b=gdEzw3/4qF0yXlRueoWiN7p1SkvSFZe4C79SykrX8Z4v7bYd6C0YWr/7nh/5BJBt9koEWPBaW4TUq5dsO7MyUx24MoJWG1W2dl72ZNmgCrY3wlVRtT8tQ7r9aMGFQ1Y+DpA6WprA7n7DpTGyEBwUcV7Up8cAWbE/Zr1HB8rLU9k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782488994; c=relaxed/simple; bh=F28JWrIedZ17+DHgzHvusZYYQKCC6LrQb+656X3FJ2Q=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=C+3kikMRfDX5Ga9d9v2ULUXilNf/iUNo2I55yIpPqEoZ8ZNetrCokTbyt5qxy+HAJa5gk3teygXX5522Dt6vvbU/989cAdpybiv+A6ivZ4yRGZHptU10y9DUj9QdkgNc3UgffD6eFxX8/e4isL1mXDx8as8SEF9kPD3gtmhCIJ0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=nec+1E15; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="nec+1E15" 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 E2D681F37; Fri, 26 Jun 2026 08:49:47 -0700 (PDT) Received: from localhost (unknown [10.2.196.114]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 006D03F632; Fri, 26 Jun 2026 08:49:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1782488992; bh=F28JWrIedZ17+DHgzHvusZYYQKCC6LrQb+656X3FJ2Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nec+1E15+1aCjiJ5Xk8YbKQ6EFSTYbImiCjfirtzZ8JYBXTo+MP/lt/ETlqmUG5ZT sdzWJlK4cSG1kHt1aZ/5utQ+UC0ETSNkqPKyCP00E0RGab/4ORX5S39PZHDzgIo03/ FSkAfeJVxFE+bWlkmncC+HOLCLflESK/llmk8250= Date: Fri, 26 Jun 2026 16:49:49 +0100 From: Leo Yan To: Jie Gan Cc: Suzuki K Poulose , Konrad Dybcio , Bjorn Andersson , Konrad Dybcio , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Tingwei Zhang , Jingyi Wang , Abel Vesa , Mike Leach , James Clark , Yuanfang Zhang , linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 2/2] arm64: dts: qcom: kaanapali: fix traceNoC probe issue Message-ID: <20260626154949.GA1812158@e132581.arm.com> References: <471d7a92-3629-4274-a303-8906d3626037@arm.com> <25d7d3a1-58e0-4f25-a73a-59a978130c47@oss.qualcomm.com> <20260624151610.GC575984@e132581.arm.com> <20260625085643.GD575984@e132581.arm.com> <065853f5-b11b-4316-814e-202f07acb6ea@oss.qualcomm.com> <20260626103015.GE575984@e132581.arm.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Jun 26, 2026 at 08:09:58PM +0800, Jie Gan wrote: [...] > I have another proposal: what if we allocate the ATID in trace_noc_id() when > the device does not already have a valid ATID? > > Possible scenarios: > > If the itnoc device is connected to a TPDM device (which has no ATID), > trace_noc_id() will be invoked via coresight_path_assign_trace_id(), and a > valid ATID can be allocated for the path. > > If the itnoc device is connected to sources other than TPDM, trace_noc_id() > will never be invoked, and therefore no ATID will be allocated for the > device, saving resources. TBH, I'm not sure I can make a judgement here, as I don't have enough knowledge of the topology. And I'm not sure whether the listed connections cover all possible cases. I also found commit 5799dee92dc2: | This patch adds platform driver support for the CoreSight Interconnect | TNOC, Interconnect TNOC is a CoreSight link that forwards trace data | from a subsystem to the Aggregator TNOC. Compared to Aggregator TNOC, | it does not have aggregation and ATID functionality. With your proposal, wouldn't ATID be allocated for the interconnect TNOC while being skipped for the Aggregator TNOC? That seems to contradict the commit log. Thanks, Leo