From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E7D9E3ED5D4; Fri, 26 Jun 2026 10:26:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782469575; cv=none; b=LHh5cKzF2mzV3bFdBX9XpW5hXR6JkbSV9YAjJR8ZxX/SFpMQATSTgLHhclGCAZtIsdGAIaTAzgrjd0Hs99UUMv1XmY31RZDjVjCihdiSm2xwaQc4BzyrYxlxpQKsMNmCCXO6tqPHc2NMK0+Z4lvEVdBOfExJXEVjhsabj2COTvw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782469575; c=relaxed/simple; bh=zNvNIOP+lA+Tu8EL824I1I9M5mhvmoXbh5ASrZCn7mo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=DNL82ZMzbA66rHosROV7SeBZXN3ThrSOtbSTEPEF9NEkuSGLlzjl5xLTYpqjmJeB5IpwT87jf0SQ2rx3eTccoe/nYuQLKtHnWMPSx+5r8b1iIM1qftWY/eUY4NZrqDC8LkmuiqsHFQZmrfieqdjZIuFCmVkf2bZjVmgiQK6//w0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=H9wvkJY/; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="H9wvkJY/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0B56A1F000E9; Fri, 26 Jun 2026 10:26:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782469567; bh=zNvNIOP+lA+Tu8EL824I1I9M5mhvmoXbh5ASrZCn7mo=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=H9wvkJY/3byFOViyxOid8+vl+SuEU6XbFgMfE5Kx+E2wHQYTE7zIofEN7S8tq2ZK8 kIGhIrlDySw50wA6u2Aif5FbF9GXefslwlrwqRsIts8SmM9XrCRQ+bGDtXl9yzXCDL YDX0C8rv3pbJEI6+Gk0E4GyVofRmEVP+Srb4+CZgzKwm+8HqYRgZ7EF00/xU+1G1jU 04EETzd3wRIJ5rr3D34NTBtf1tUc6I1W47JroPm/WMa4YjlJTxwdpPJ3Pjkwtk0vHO YLSIWkmJiCCiO/ulSCrwNXFwC0jjK2rldL5IPuwxNgkomYNZ/gKa1Dfm24gIi6MQxw K46CS12YOskUA== Date: Fri, 26 Jun 2026 12:26:03 +0200 From: Krzysztof Kozlowski To: Mikko Perttunen Cc: Thierry Reding , Jonathan Hunter , David Airlie , Simona Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Rob Herring , Krzysztof Kozlowski , Conor Dooley , linux-tegra@vger.kernel.org, dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/4] dt-bindings: display: tegra: Add channel/syncpoint range properties Message-ID: <20260626-sceptical-aardvark-from-mars-cedf81@quoll> References: <20260622-host1x-nohv-v1-0-65bc682a617f@nvidia.com> <20260622-host1x-nohv-v1-2-65bc682a617f@nvidia.com> <20260625-poetic-heavy-vulture-7baabb@quoll> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: On Thu, Jun 25, 2026 at 06:26:43PM +0900, Mikko Perttunen wrote: > On Thursday, June 25, 2026 5:36=E2=80=AFPM Krzysztof Kozlowski wrote: > > On Mon, Jun 22, 2026 at 05:22:51PM +0900, Mikko Perttunen wrote: > > > Channels and syncpoints available may be limited when other system > >=20 > > What are channels and syncpoints? >=20 > Very host1x-specific hardware resources. Somewhat close to GPU channels > and semaphores / fences if you're familiar with those. >=20 > >=20 > > > components are using them. Add properties nvidia,channels and > > > nvidia,syncpoints to limit the range of usable channels and/or > > > syncpoints. > >=20 > > Why isn't this deducible from the compatible? >=20 > When Host1x is partitioned, the hypervisor (or other software entity > with access to the non-vm host1x register regions) can configure which > channels and syncpoints are available to each partition arbitrarily. So you will have different boards for the same SoC with different values? >=20 > How that partitioning was done is not discoverable through hardware > directly, so we need to pass that information through device tree. >=20 > >=20 > > Also, nvidia,channels is too broad/generic. This is not ADC, right? And > > channels is a common term in IIO. And in few other cases. >=20 > It's not ADC. Yes, it's a common term in a lot of contexts. I can call > it nvidia,host1x-channels if you prefer but that seems a bit redundant > given the context. host1x is indeed poor, but maybe there is some way to be a bit more descriptive? message-channels? Best regards, Krzysztof