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 6E2F13FFAA8; Thu, 26 Mar 2026 15:24:40 +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=1774538680; cv=none; b=qyu1Pwtnyl+UouyU3/CtVgpOF8z/QCvMrz1q+KwbynbObpk3f/99Ah338fsU+UPmWSTi+yHT3X7wkCYnvZKvctpjcHjJjzK+/fSa4t0NaACnFUYKqmVDELfyVA7tJuyYPfCjumfbpSt+ISVC7ejNE7PbtV/2SreApXbAZuo0+zA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774538680; c=relaxed/simple; bh=VC8lDUeLQaF89olSSrKq5JgPweNUCYlwAaUQYICMSVc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=A7fmLGpL0kqkmEA1U3qaMOW3m6tFN5WUIMmWsWZoWCeQKyYkq6/wd4xvm2eZbqR1zD6E0z8rdK1hg/m7J4ItiTbZFYBEWHOtyTH/cVkPHA9yctOgXEvnjhjvF8ji5ex6Z6wAq8sZbll5zkiJWkFxt56b5EgrrgzmeizfptGmtR4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kaAEnN52; 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="kaAEnN52" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D8768C19423; Thu, 26 Mar 2026 15:24:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774538680; bh=VC8lDUeLQaF89olSSrKq5JgPweNUCYlwAaUQYICMSVc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=kaAEnN52eATLIBzXKxWYkAjEQF54lvKDkYc4MOirqFrd5bD5DAIMQRi7Z6XFDonBb WKa61FlMkBcd/iXQJ6NVvj56BLrUfSeujVI4srqkrjEo0YNkS+P6/Xr/rSzIa4TTE8 2nnxiSlLoWZ9fwxqX9ylNk7h2LFe47bb/mfRrR6P0j9DmK3EzFipJ7bxp5c8xm2TuS NiMdnWVRBzuXH1POPXiMkAnG50ifQBOXsOongqLa/bTPgKB4QNBbt70yCIYs0d7SRq J1Ih9mzFlDLWUDBMRSL14ekNbotN/3lElMlAvI5lwEmHOwIOUc4QCgy+qNYqG3bT9G pKTZSBiYPPjOg== Date: Thu, 26 Mar 2026 10:24:36 -0500 From: Rob Herring To: Ahmed Tiba Cc: linux-acpi@vger.kernel.org, devicetree@vger.kernel.org, linux-cxl@vger.kernel.org, Michael.Zhao2@arm.com, linux-arm-kernel@lists.infradead.org, Dmitry.Lamerov@arm.com, rafael@kernel.org, conor@kernel.org, will@kernel.org, bp@alien8.de, catalin.marinas@arm.com, krzk+dt@kernel.org, linux-doc@vger.kernel.org, mchehab+huawei@kernel.org, tony.luck@intel.com Subject: Re: [PATCH v3 09/10] dt-bindings: firmware: add arm,ras-cper Message-ID: <20260326152436.GA2484010-robh@kernel.org> References: <20260318-topics-ahmtib01-ras_ffh_arm_internal_review-v3-0-48e6a1c249ef@arm.com> <20260318-topics-ahmtib01-ras_ffh_arm_internal_review-v3-9-48e6a1c249ef@arm.com> Precedence: bulk X-Mailing-List: linux-doc@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: <20260318-topics-ahmtib01-ras_ffh_arm_internal_review-v3-9-48e6a1c249ef@arm.com> On Wed, Mar 18, 2026 at 08:48:06PM +0000, Ahmed Tiba wrote: > Describe the DeviceTree node that exposes the Arm firmware-first > CPER provider and hook the file into MAINTAINERS so the > binding has an owner. > > Signed-off-by: Ahmed Tiba > --- > .../devicetree/bindings/firmware/arm,ras-cper.yaml | 71 ++++++++++++++++++++++ > MAINTAINERS | 5 ++ > 2 files changed, 76 insertions(+) > > diff --git a/Documentation/devicetree/bindings/firmware/arm,ras-cper.yaml b/Documentation/devicetree/bindings/firmware/arm,ras-cper.yaml > new file mode 100644 > index 000000000000..bd93cfb8d222 > --- /dev/null > +++ b/Documentation/devicetree/bindings/firmware/arm,ras-cper.yaml > @@ -0,0 +1,71 @@ > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/firmware/arm,ras-cper.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Arm RAS CPER provider > + > +maintainers: > + - Ahmed Tiba > + > +description: | > + Arm Reliability, Availability and Serviceability (RAS) firmware can expose > + a firmware-first CPER error source directly via DeviceTree. Firmware > + provides the CPER Generic Error Status block and notifies the OS through > + an interrupt. > + > +properties: > + compatible: > + const: arm,ras-cper > + > + reg: > + minItems: 1 > + items: > + - description: > + CPER Generic Error Status block exposed by firmware > + - description: > + Optional 32- or 64-bit doorbell register used on platforms > + where firmware needs an explicit "ack" handshake before overwriting > + the CPER buffer. Firmware watches bit 0 and expects the OS to set it > + once the current status block has been consumed. > + > + interrupts: > + maxItems: 1 > + description: > + Interrupt used to signal that a new status record is ready. > + > + memory-region: > + $ref: /schemas/types.yaml#/definitions/phandle memory-region already has a defined type. You just need to define how many entries (maxItems: 1). > + description: > + Optional phandle to the reserved-memory entry that backs the status > + buffer so firmware and the OS use the same carved-out region. > + > +required: > + - compatible > + - reg > + - interrupts > + > +additionalProperties: false > + > +examples: > + - | > + #include > + > + reserved-memory { > + #address-cells = <2>; > + #size-cells = <2>; > + ras_cper_buffer: cper@fe800000 { > + reg = <0x0 0xfe800000 0x0 0x1000>; > + no-map; > + }; > + }; > + > + error-handler@fe800000 { > + compatible = "arm,ras-cper"; > + reg = <0xfe800000 0x1000>, Wait! Why is the reserved address here? There's 2 problems with that. There shouldn't be same address in 2 places in the DT. The 2nd is reserved memory should only be regions within DRAM (or whatever is system memory). Rob