From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 9828083CC9; Thu, 21 Mar 2024 13:32:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711027973; cv=none; b=ByXATUIALwCwaLIg/uBvHmFbR2u+a5wEe4uipyRA37UdMJm2V2gsUteeaJ8ZTOBFzYp/ZR99PjaoRiuCJ7cOvc7EuEIeHgWgtgf590+seru26WZQP4EPVpubaygurXIkS1htB3WZcBi3fz4c8nXfThufZHa19ybcgOVy0wZ/B1A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711027973; c=relaxed/simple; bh=U4+3vwCSjy3fEIwZBChHYsiJozqRlEPMAlHzlGK6vwc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=e6k2qel1ktunGQwQmD17KzXFWGnUTqu9+pmEWmOFqAWCsMQtJxtjZ8GLtDEo4ZMskKAkNv5EkPXulOW1MhIyb/HhjzJ/dT4fi1weV1aQuC6iPyx4wRLupRFLru22QtsoBK8okZ5ApR0IhabA1mf1fP+NyqSUQIniNg4ffyiIQhY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=SPnRGmSi; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="SPnRGmSi" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0068DC433F1; Thu, 21 Mar 2024 13:32:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711027973; bh=U4+3vwCSjy3fEIwZBChHYsiJozqRlEPMAlHzlGK6vwc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=SPnRGmSiHpVQdgumJveGdl+QUflxSvzlU5oJDsw+78Qtdme49Ewn95IHMy4AzuPXd f0gXOu3eFmBNiWhwl+jnx2dAsinb8BvP9i86Pj4jPLZ4Zaj0swaHoZEnKDAh3IVkEU OfDvosEWyjTVDRtJdW74w2FltY0HdxzG4Srx9AWCfgahhyRG0nUoZz3Wo/iFEORTrK jVCU5FMScrKgkfxwLVPovuWoF9ewSW/jfxz7GlSLbZvuL8JZ46AN7L2whVVzLSF6IF 8/vRkD3LwKvjGEEN1wUuQexKET3qPp96DNWWXMd46mqE6f+VvRrK71P8IXWnxecP2q LUN7NXf9m3jaQ== Date: Thu, 21 Mar 2024 08:32:50 -0500 From: Rob Herring To: David Woodhouse Cc: Krzysztof Kozlowski , Sudan Landge , tytso@mit.edu, Jason@zx2c4.com, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org, sathyanarayanan.kuppuswamy@linux.intel.com, thomas.lendacky@amd.com, dan.j.williams@intel.com, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, graf@amazon.de, bchalios@amazon.es, xmarcalx@amazon.co.uk, ardb@kernel.org, benh Subject: Re: [PATCH v1 0/4] virt: vmgenid: Add devicetree bindings support Message-ID: <20240321133250.GA1600070-robh@kernel.org> References: <20240319143253.22317-1-sudanl@amazon.com> <23692c07-98bd-477d-b244-bba14c50352c@linaro.org> <38aad6c0e698c8e804694276d1762d61f2068ce8.camel@infradead.org> <20240320161531.GA1810860-robh@kernel.org> <60404403932a984d1f75d111ff53b9053af03579.camel@infradead.org> 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: <60404403932a984d1f75d111ff53b9053af03579.camel@infradead.org> On Wed, Mar 20, 2024 at 04:55:45PM +0000, David Woodhouse wrote: > On Wed, 2024-03-20 at 11:15 -0500, Rob Herring wrote: > > On Wed, Mar 20, 2024 at 01:50:43PM +0000, David Woodhouse wrote: > > > On Tue, 2024-03-19 at 16:24 +0100, Krzysztof Kozlowski wrote: > > > > On 19/03/2024 15:32, Sudan Landge wrote: > > > > > This small series of patches aims to add devicetree bindings support for > > > > > the Virtual Machine Generation ID (vmgenid) driver. > > > > > > > > > > Virtual Machine Generation ID driver was introduced in commit af6b54e2b5ba > > > > > ("virt: vmgenid: notify RNG of VM fork and supply generation ID") as an > > > > > ACPI only device. > > > > > We would like to extend vmgenid to support devicetree bindings because: > > > > > 1. A device should not be defined as an ACPI or DT only device. > > > > This (and the binding patch) tells me nothing about what "Virtual > > Machine Generation ID driver" is and isn't really justification for > > "why". > > It's a reference to a memory area which the OS can use to tell whether > it's been snapshotted and restored (or 'forked'). A future submission > should have a reference to something like > https://www.qemu.org/docs/master/specs/vmgenid.html or the Microsoft > doc which is linked from there. That doc mentions fw_cfg for which we already have a binding. Why can't it be used/extended here? Rob [1] https://www.kernel.org/doc/Documentation/devicetree/bindings/firmware/qemu%2Cfw-cfg-mmio.yaml