From patchwork Wed Apr 20 12:06:01 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Fabio Estevam X-Patchwork-Id: 12820150 X-Patchwork-Delegate: herbert@gondor.apana.org.au Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B3BCDC4332F for ; Wed, 20 Apr 2022 12:06:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378383AbiDTMJH (ORCPT ); Wed, 20 Apr 2022 08:09:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46528 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1378390AbiDTMJG (ORCPT ); Wed, 20 Apr 2022 08:09:06 -0400 Received: from mail-oi1-x22b.google.com (mail-oi1-x22b.google.com [IPv6:2607:f8b0:4864:20::22b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0CA5436B5E; Wed, 20 Apr 2022 05:06:16 -0700 (PDT) Received: by mail-oi1-x22b.google.com with SMTP id q129so1780876oif.4; Wed, 20 Apr 2022 05:06:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=3vowEc/UcKrf0koZfGRpVEA6e8Y7oEc/jUqdJ2tAL84=; b=jcyJFLN7iLtNwhQplscp/7lkiD3lUsBJYoMNER1K9C8tMZVQBnOjD9ZHTDGFenS3iw KRHuFRotqrp3XdXYb8yNkWqZ4rgUAk7HPBm1X3knRHXgqhuSvp9sY/gpeZq2Dly2JDZe 6g0bQbPRv+vQfwV86livDx9BGKlLkj9bM15OZhXZiwUXDoiDccf7v3JAJ2L8x+uk5vtS DsnUvuCalpEopSXZeqm34KQfpljHx1H1xqOjb7u9aklTn0b7xroirqjbUSX3IZA9YIjY eSWJ++j+eNdJV0TRcYsmVGvoLuHusCJ3Eoho1V0kPHL4eLUW/IVjmlUjIfMEMKeBybk9 gzZw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=3vowEc/UcKrf0koZfGRpVEA6e8Y7oEc/jUqdJ2tAL84=; b=VCZo7wsioP6AIGKD3Yn0JuxqKiKrJCaAir1+fED4+Q6rn8rAmg4Isvs58Ch9RW6mCk bfvheB/u62uFIJmB/V7UWlp5LLsPMN4KmHZyQrOumvhcEVmAfBv449u6vIMkBtJwIkmD +HyHuaPf9zN8yi4GTxVwmQNB6uMDmy4ksZeSRXCHoUpr0ZqseSEIowM2IeOHCtEWCQrQ gIH69EyhVs6qfFZ333BO1gCFbtE5wgG397WKjswSYc5uwMXWec516ZbFrTDz7LZie1/2 ItT6ClNT5tPu+A/5pvo7ZQh/jznRezCzmu1cZKlko1wKgL3erLyPyQ78/GHI6YKu8LI+ Vm7Q== X-Gm-Message-State: AOAM530ttWcPZHHDmv2koN2/suiZsyqiHyqoayrWeDG0PNc9XC3+M087 dNZVEPwSyQp5M1mj8I6tc6w= X-Google-Smtp-Source: ABdhPJwsNWZ8orbLQ9FaPtyH2jT9tIe9jmb2LyslC/t4DMOVlyEoawNvgSZg6apMloqb/NonKCgNnw== X-Received: by 2002:a05:6808:128c:b0:2da:3751:7639 with SMTP id a12-20020a056808128c00b002da37517639mr1552321oiw.294.1650456375325; Wed, 20 Apr 2022 05:06:15 -0700 (PDT) Received: from localhost.localdomain ([2804:14c:485:4b69:3ce1:a87b:51c0:189d]) by smtp.gmail.com with ESMTPSA id o19-20020a4a9593000000b0032176119e65sm6530117ooi.34.2022.04.20.05.06.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Apr 2022 05:06:14 -0700 (PDT) From: Fabio Estevam To: herbert@gondor.apana.org.au Cc: horia.geanta@nxp.com, gaurav.jain@nxp.com, V.Sethi@nxp.com, linux-crypto@vger.kernel.org, Fabio Estevam , stable@vger.kernel.org Subject: [PATCH v5] crypto: caam - fix i.MX6SX entropy delay value Date: Wed, 20 Apr 2022 09:06:01 -0300 Message-Id: <20220420120601.1015362-1-festevam@gmail.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org From: Fabio Estevam Since commit 358ba762d9f1 ("crypto: caam - enable prediction resistance in HRWNG") the following CAAM errors can be seen on i.MX6SX: caam_jr 2101000.jr: 20003c5b: CCB: desc idx 60: RNG: Hardware error hwrng: no data available This error is due to an incorrect entropy delay for i.MX6SX. Fix it by increasing the minimum entropy delay for i.MX6SX as done in U-Boot: https://patchwork.ozlabs.org/project/uboot/patch/20220415111049.2565744-1-gaurav.jain@nxp.com/ As explained in the U-Boot patch: "RNG self tests are run to determine the correct entropy delay. Such tests are executed with different voltages and temperatures to identify the worst case value for the entropy delay. For i.MX6SX, it was determined that after adding a margin value of 1000 the minimum entropy delay should be at least 12000." Cc: Fixes: 358ba762d9f1 ("crypto: caam - enable prediction resistance in HRWNG") Signed-off-by: Fabio Estevam Reviewed-by: Horia Geantă Reviewed-by: Vabhav Sharma Reviewed-by: Gaurav Jain --- Changes since v4: - Change the function name to needs_entropy_delay_adjustment() - Vabhav - Improve the commit log by adding the explanation from the U-Boot patch - Vabhav drivers/crypto/caam/ctrl.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/drivers/crypto/caam/ctrl.c b/drivers/crypto/caam/ctrl.c index ca0361b2dbb0..f87aa2169e5f 100644 --- a/drivers/crypto/caam/ctrl.c +++ b/drivers/crypto/caam/ctrl.c @@ -609,6 +609,13 @@ static bool check_version(struct fsl_mc_version *mc_version, u32 major, } #endif +static bool needs_entropy_delay_adjustment(void) +{ + if (of_machine_is_compatible("fsl,imx6sx")) + return true; + return false; +} + /* Probe routine for CAAM top (controller) level */ static int caam_probe(struct platform_device *pdev) { @@ -855,6 +862,8 @@ static int caam_probe(struct platform_device *pdev) * Also, if a handle was instantiated, do not change * the TRNG parameters. */ + if (needs_entropy_delay_adjustment()) + ent_delay = 12000; if (!(ctrlpriv->rng4_sh_init || inst_handles)) { dev_info(dev, "Entropy delay = %u\n", @@ -871,6 +880,15 @@ static int caam_probe(struct platform_device *pdev) */ ret = instantiate_rng(dev, inst_handles, gen_sk); + /* + * Entropy delay is determined via TRNG characterization. + * TRNG characterization is run across different voltages + * and temperatures. + * If worst case value for ent_dly is identified, + * the loop can be skipped for that platform. + */ + if (needs_entropy_delay_adjustment()) + break; if (ret == -EAGAIN) /* * if here, the loop will rerun,