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 X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77A0DC432BE for ; Sun, 1 Aug 2021 16:26:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 560F260EBD for ; Sun, 1 Aug 2021 16:26:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229777AbhHAQ02 (ORCPT ); Sun, 1 Aug 2021 12:26:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:39638 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229665AbhHAQ00 (ORCPT ); Sun, 1 Aug 2021 12:26:26 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C8EDE61059; Sun, 1 Aug 2021 16:26:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1627835178; bh=wpnk83J5W52Cehu0wTsNOKGTslGIXxW1DA6xKjVj57M=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=DnAh/UDly7Bn0jw4Rv0lAOs+BP9fRFpRJ/mOb6SlFksnOaustk1C1zIKWJdaGLcN3 prkT96qGygOkaS0SMa5L7B6uyFneKgHoAqxdhdLOco0PCXlKrN9FShTZRwIqNVPkJB uLPFH1/9vLf9bRkaXt/TJMlZ348c8BM6orf/ckyV+tSmRBC3Fyb2YZRDoEKyrcExHP 4glY7k39R4pPFuut4CXMiZ3wNE7qeAkxW4yXFzOEJxxkbD26vkoD3M8+oHAR1L17Lr EpOc4yaoEJfn2uTAIN/Ltcpnywu0vZ4t4befktkosYOICOGU2MjDU3SMXxjJ3+aWiQ jIakZzd4Ac4sw== Received: by mail-oi1-f179.google.com with SMTP id n16so14652745oij.2; Sun, 01 Aug 2021 09:26:18 -0700 (PDT) X-Gm-Message-State: AOAM532yTa0IZ+KFzRPniqbjwEj9U4gdy7jxqH2bstLf6WHKzD+1CQKp BYc+KsQtSj6m1hctPd4rdoouGgU+ztkTrpx9BMI= X-Google-Smtp-Source: ABdhPJz3/6J0OezwIAj9JxW632NldoAZOtXTofqhaWRPClx/rrb07RmsWgwSX5m18t60pV6FqwLR/lwyOr+i31b1/gs= X-Received: by 2002:aca:4c49:: with SMTP id z70mr7775755oia.174.1627835178131; Sun, 01 Aug 2021 09:26:18 -0700 (PDT) MIME-Version: 1.0 References: <20210731204845.21196-1-andre.przywara@arm.com> In-Reply-To: <20210731204845.21196-1-andre.przywara@arm.com> From: Ard Biesheuvel Date: Sun, 1 Aug 2021 18:26:06 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v4 0/2] hwrng: Add Arm SMCCC TRNG based driver To: Andre Przywara Cc: Matt Mackall , Herbert Xu , Mark Rutland , Lorenzo Pieralisi , Sudeep Holla , Linux Crypto Mailing List , Linux ARM , Linux Kernel Mailing List , Benjamin Herrenschmidt , Mark Brown , Will Deacon , Ali Saidi , Jon Nettleton Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 31 Jul 2021 at 22:49, Andre Przywara wrote: > > The "Arm True Random Number Generator Firmware Interface"[1] provides > an SMCCC based interface to a true hardware random number generator. > So far we are using that in arch_get_random_seed(), but it might be > useful to expose the entropy through the /dev/hwrng device as well. This > allows to assess the quality of the implementation, by using "rngtest" > from the rng-tools package, for example. > > Patch 1 creates a platform device, triggered by the previous discovery > of the SMCCC TRNG service. > Patch 2 implements a hw_random platform driver, which is instantiated > through this said platform device. > > The driver can be loaded as module, or built into the kernel. > > [1] https://developer.arm.com/documentation/den0098/latest/ > > Changelog v3 ... v4: > - drop pointless driver loading message > - drop unneeded init() routine > > Changelog v2 ... v3: > - split platform device and driver > > Changelog v1 ... v2: > - fix building as a module > - de-register device upon exit > - mention module name in Kconfig > > Andre Przywara (2): > firmware: smccc: Register smccc_trng platform device > hwrng: Add Arm SMCCC TRNG based driver > Reviewed-by: Ard Biesheuvel > drivers/char/hw_random/Kconfig | 14 +++ > drivers/char/hw_random/Makefile | 1 + > drivers/char/hw_random/arm_smccc_trng.c | 123 ++++++++++++++++++++++++ > drivers/firmware/smccc/smccc.c | 17 ++++ > 4 files changed, 155 insertions(+) > create mode 100644 drivers/char/hw_random/arm_smccc_trng.c > > -- > 2.17.6 >