From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4C22E606A319 for ; Thu, 22 Oct 2026 13:17:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=iq/Gwtu/; dkim=pass (1024-bit key, unprotected) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=kaMcGbEQ 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-Unsubscribe-Post:List-Owner; bh=eQf4Ux3KgpPvYJ/vZ/XrAxGRYNkjOFHzjKZYgsvPaUA=; b=iq/Gwtu/ODKqvh0LLLFjvN3vOH hjsCr2d1iknJhUHxSaGOIg3U08dG4taQxQ8TDpzMnPz1BLXNNSDWZ3WHxkOrRIaJaDDyREAJSuofm ph2cv9abQIEi7LgV7NHs+sXion0C+jWLljJ6xHoKyde326AeHql/NOdgbblIyFU/e7uI440ChG3vw VkMviEM5z1gIf+/8wEuJanta/rVqhB43uNG118cwgBlGkq7rYhZDFIvFOSrERHGXFCbBqh5WuwoLe l+c+pNLkcPS8q5sQCo2YW6v7atgWjRWR3ovo8/GThZ6VJTY5mhXBz8uFiYwf3b+HMtqQBLZDEPKQ1 vipw7ACQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xJsfm-0000000EABT-0hD4; Thu, 22 Oct 2026 13:17:34 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xJsfj-0000000EAB5-2IBG for linux-arm-kernel@lists.infradead.org; Thu, 22 Oct 2026 13:17:32 +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 541412C34; Thu, 22 Oct 2026 06:17:24 -0700 (PDT) Received: from e129823.arm.com (e129823.arm.com [10.2.213.3]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8CAB13F673; Thu, 22 Oct 2026 06:17:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1792675047; bh=0s7bfEvTJgNfIljZiLJWu7OAwfMP+SubhPZFX3IkXwQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=kaMcGbEQxmy0Ec8g7NLwAJplIEgN0KZqDZ25nJ9T+y9vCYjJMo4N09+X/gtUyZjEB QaI8BY1cstU+Ae4jAhbmNYNh9x9UWMtawAEkMuKUfaokNLXw9ksxMfZq8wYGR9x+Zv eqVWgSjmgDaE+Lukag3OFgdzIjpd/YkWqjS5jn/A= Date: Thu, 22 Oct 2026 14:17:23 +0100 From: Yeoreum Yun To: Kohei Enju Cc: Yeoreum Yun , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Lorenzo Pieralisi , Catalin Marinas , Suzuki Poulose , Steven Price , Sami Mujawar , "Aneesh Kumar K.V" , Jiri Pirko , GONG Ruiqi , Jason Gunthorpe Subject: Re: [PATCH RFC 1/3] firmware: arm_firme: introduce arm_firme driver Message-ID: References: <20261019-firme_interface-v1-0-27895c9cebaa@arm.com> <20261019-firme_interface-v1-1-27895c9cebaa@arm.com> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261022_061731_657525_0CD2C131 X-CRM114-Status: GOOD ( 18.73 ) X-Spam-Score: -4.4 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-10.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Thu, Oct 22, 2026 at 06:48:49PM +0900, Kohei Enju wrote: > On 10/19 15:14, Yeoreum Yun wrote: > > The Realm Management Extension (FEAT_RME) is part of Arm Confidential > > Compute Architecture (CCA) and enables support for dynamic, attestable > > trusted execution environments ("Realms") on Arm systems. > > > > Realm management flows depend on EL3 firmware for operations such as > > Realm construction, resource allocation and isolation, and attestation > > of initial Realm state. > > > > The FIRME defines standard interfaces provided by EL3 firmware to > > satisfy these dependencies. These interfaces include: > > > > - Granule Protection Table management > > - IDE key management for PCIe and CXL Root Ports > > - Memory Encryption Context management > > - Attestation token management > > - Integrated device management > > > > Each group of interfaces forms a FIRME service. A base FIRME service > > is also defined to provide common concepts, service discovery, and > > feature discovery across services. > > > > FIRME interfaces are implemented at the EL3 boundary between the > > Non-secure, Realm, and Secure states. They may also be used on systems > > without FEAT_RME, for example to provide firmware-based attestation or > > security services. > > > > arm_firme driver provides the common FIRME framework and service discovery > > support for client drivers using below FIRME services: > > > > - Base service. > > - Attestation token management. > > > > Signed-off-by: Yeoreum Yun > > Does this series assume that the kernel is running in EL2 implicitly? > > The FIRME spec says: > An implementation of one or more FIRME services at a valid Exception level boundary between EL3 and the > highest Exception level in a different Security state is called a FIRME instance. > > and I think only NS-EL2 can call FIRME interfaces as a NS FIRME > instance, right? Yeap. but it doens't forbid calling the FIRME from EL1 too. As a just example, when the host running with pkvm, it could use where kernel running as EL1. [...] -- Sincerely, Yeoreum Yun