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 8751B369D5A; Tue, 30 Jun 2026 08:10:24 +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=1782807025; cv=none; b=MyznWWxQ2Nc/IP80mms6Hn6fLH5i8GZIQ4qan8QhBD68E0c6AS0OqDu0Tj5SuNvluc4pxBBf4zzR9/BOZX9SfjjLGrpGWxx3IoOnAxlitH90qfo2y1wNBzFR+yr+FTwVqpvgUJY5T3zEw4PSKaLy//CGI2UxghydPT1YsgxdH/U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782807025; c=relaxed/simple; bh=Y44WNqCqpvHywWSbjQZkdja/2YAXek3Djdm80xnI13M=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=EC+PQ1iA9t53TWUWSelGSrP6NSTIHd/nqTTFDo4endL4B0W56gygD9Iug+hBPliFbeizqOLs4wrmgwepRdVMlWlZGTbOc9crTY0nntn9ZDLW0YrGnzcBY9sFmxF63wTX3ch9psdUi1CYQyGqzr5FGCNRtB08OSv1XsYU+orr6JI= 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=F+Tiyq6Z; 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="F+Tiyq6Z" 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 77C7E22D9; Tue, 30 Jun 2026 01:10:19 -0700 (PDT) Received: from localhost (unknown [10.2.196.114]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 709923F905; Tue, 30 Jun 2026 01:10:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1782807023; bh=Y44WNqCqpvHywWSbjQZkdja/2YAXek3Djdm80xnI13M=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=F+Tiyq6Z2r/ysjEKRkLNrZe7WjxZIFrfI16Q00mNuwaXZzLMYamHP76j8c0Oj0ZCx oATd1jsV20bjvkqASMMW347xXShaAapUryOwNBm+XzYUyZ3gjF4T51Lf8EwdFwn8IR kDB0PB5aoGQRJlOi/uL4tsBaGPeeiVJoJ3GJTmgs= Date: Tue, 30 Jun 2026 09:10:21 +0100 From: Leo Yan To: Jie Gan Cc: Suzuki K Poulose , Mike Leach , James Clark , Konrad Dybcio , Bjorn Andersson , Konrad Dybcio , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Tingwei Zhang , Jingyi Wang , Abel Vesa , 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: <20260630081021.GD1812158@e132581.arm.com> References: <20260624151610.GC575984@e132581.arm.com> <20260625085643.GD575984@e132581.arm.com> <065853f5-b11b-4316-814e-202f07acb6ea@oss.qualcomm.com> <20260626103015.GE575984@e132581.arm.com> <20260626154949.GA1812158@e132581.arm.com> <9432df20-08bf-4134-b4b9-e6b5d618af81@oss.qualcomm.com> <20260629142848.GB1812158@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: Hi Jie, On Tue, Jun 30, 2026 at 09:03:52AM +0800, Jie Gan wrote: [...] > > - How can you guarantee that a interconnect TraceNoC will never > > require ATID in the future? > From a hardware perspective, there is no fundamental difference between an > itnoc and an AG TraceNoC. They use the same TraceNoC hardware implementation > and share the same AMBA bus type. The distinction is purely functional: an > itnoc is used for local trace aggregation within a subsystem, whereas an AG > TraceNoC serves as the top-level aggregation point for the SoC. I'm still not convinced that adding "arm,primecell-periphid" is the right approach. >From the description above, I'd expect either the hardware to expose bits in a register to distinguish these two module types, or as I suggested earlier, to use a DT property to indicate the module type (or whether ATID is required). Or have you tried to detect the last tnoc on a path and allocate ID for it? (You can retrieve csdev->path). Thanks, Leo