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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 88E3DCDB479 for ; Wed, 24 Jun 2026 15:16:23 +0000 (UTC) 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-Owner; bh=k24+zt0rfnYQxi626h0DuXxdL/2faB7sC7masLcnUEM=; b=4CLy8OVrbWwgc4NX/Bjj/vFQv/ ZHIEQ+HFVOhxswGbIFWmT5p5sHns+Z5+WDOLXxwFq8+iGUc0pmm/kLCSOuS7p8eX+aHRVstP6lxOf t7cN+i90JtiCJWN3XlQMvRjqrotUSbfA6JhD2yWQT6nzNI5vO6QqvSGBpR9HOAtWUgmfHJH3MAUnN dmI/9YqizLPFdlhJxiMiM4v0flVC6HAyVz1awTU93OMMWeNcRHzKQvpE5H/LYYeBMLc/WrjAEYOWe BwBGPDygT2Y9Qa8u7DNIuJ1vlgy0ZQQrJioqjRC9Q4n2VqsnIRs7BnKT1N7KyQe0N7OnJlC2Uvow5 v/xRLPqw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wcPKr-00000007yo4-04nN; Wed, 24 Jun 2026 15:16:17 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wcPKo-00000007ynb-3L1i for linux-arm-kernel@lists.infradead.org; Wed, 24 Jun 2026 15:16:16 +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 D60602308; Wed, 24 Jun 2026 08:16:08 -0700 (PDT) Received: from localhost (unknown [10.2.196.114]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 01EAD3F905; Wed, 24 Jun 2026 08:16:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1782314173; bh=PX10r5f9OoO8qOWEx/oZ9VqNT3djQJ+d35yaUiPexng=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=BmBZGjT4U3qcNtktNVR/2XoYS3e6/c+LO8+3D5K7T+hH/5zmpU0WSE2VIm9ZpaUsW GpozDJqWM3t+QRFsHr9Eq2dqg7Bra5Z6r3HJCfidsc1hnl5eyoRv8/WUNeTTsuHuHD +RZhpP0fYme53aFTKa6uhjX+//zPxUOuHUSzf2r4= Date: Wed, 24 Jun 2026 16:16:10 +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: <20260624151610.GC575984@e132581.arm.com> References: <20260624-fix-tracenoc-probe-issue-v2-0-786520f62f21@oss.qualcomm.com> <20260624-fix-tracenoc-probe-issue-v2-2-786520f62f21@oss.qualcomm.com> <471d7a92-3629-4274-a303-8906d3626037@arm.com> <25d7d3a1-58e0-4f25-a73a-59a978130c47@oss.qualcomm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <25d7d3a1-58e0-4f25-a73a-59a978130c47@oss.qualcomm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260624_081614_880947_1E5A5775 X-CRM114-Status: GOOD ( 18.03 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jun 24, 2026 at 11:08:32PM +0800, Jie Gan wrote: [...] > > Why does it fail ? power management ? hw broken ? Is it really AMBA or > > do you pretend that to be an AMBA device by faking the CID/PID? > > The CID reads as 0 from the register, which I suspect is a hardware design > issue. I have not yet confirmed this with the hardware team. As a > workaround, I provided a fake periphid via a DT property to bypass > amba_read_periphid. > > > Leo commented in other thread: > >>tnoc.c registers both an AMBA driver and a platform driver. Shouldn't >>it > >>be registered as a platform device instead? > > The platform driver is intended for the interconnect TraceNoC device and is > not designed to allocate an ATID. The issue is that the TPDM device borrows > the ATID from the TraceNoC device, resulting in the ATID always being 0 when > associated with an interconnect NoC device. > > However, I believe it is acceptable to allocate an ATID for the itNoC device > and the issue can be fixed with this way. I think so.