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=-6.7 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED 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 15A4EC04A6B for ; Wed, 8 May 2019 06:40:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4BD6220989 for ; Wed, 8 May 2019 06:40:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=chronox.de header.i=@chronox.de header.b="nui6JYUl" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726526AbfEHGkd (ORCPT ); Wed, 8 May 2019 02:40:33 -0400 Received: from mo4-p01-ob.smtp.rzone.de ([85.215.255.51]:9945 "EHLO mo4-p01-ob.smtp.rzone.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725884AbfEHGkd (ORCPT ); Wed, 8 May 2019 02:40:33 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1557297629; s=strato-dkim-0002; d=chronox.de; h=References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: X-RZG-CLASS-ID:X-RZG-AUTH:From:Subject:Sender; bh=SsUTm1R7UUQ+bTJ7Pc64aIfy+AkoXx22RxCukswczwc=; b=nui6JYUltmmXKziARr5q7vpF1EB//MpMo8eVgZwQnVBTiz3MeIBV9jb4+gAT660b6a hY4WdVllifXJ8gCxjayJEMpvClZU5gV/CvXYxaE6Bd2DttzKVCuVRKSv8uCyi3m8nIB5 vs5AX06a+5+GDr3A+lqd+/IIhofulYuXeXGhXWEo4tjKI9zIRI0eBYATr7D+Srok8Pvi ojkhb8wIxWAYFxu6u0ad66VEfH4NmesmHitzu962gfVp4j4Z8jaQTUQMFMDfNU4caukJ S8T/Z6j2XIU7B0NyAE5tGqMcEOvI6X/a2jTmmJrOOxwAfBnKjpuw9aLsKcU1i3pBoHKD C09Q== X-RZG-AUTH: ":P2ERcEykfu11Y98lp/T7+hdri+uKZK8TKWEqNyiHySGSa9k9xmwdNnzGHXPbIvSbR/w=" X-RZG-CLASS-ID: mo00 Received: from tauon.chronox.de by smtp.strato.de (RZmta 44.18 DYNA|AUTH) with ESMTPSA id R0373fv486YM8ZU (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (curve secp521r1 with 521 ECDH bits, eq. 15360 bits RSA)) (Client did not present a certificate); Wed, 8 May 2019 08:34:22 +0200 (CEST) From: Stephan Mueller To: neal.liu@mediatek.com Cc: mpm@selenic.com, herbert@gondor.apana.org.au, robh+dt@kernel.org, mark.rutland@arm.com, matthias.bgg@gmail.com, wsd_upstream@mediatek.com, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-mediatek@lists.infradead.org Subject: Re: [PATCH 3/3] hwrng: add mt67xx-rng driver Date: Wed, 08 May 2019 08:34:22 +0200 Message-ID: <12193108.aNnqf5ydOJ@tauon.chronox.de> In-Reply-To: <1557287937-2410-4-git-send-email-neal.liu@mediatek.com> References: <1557287937-2410-1-git-send-email-neal.liu@mediatek.com> <1557287937-2410-4-git-send-email-neal.liu@mediatek.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Mittwoch, 8. Mai 2019, 05:58:57 CEST schrieb neal.liu@mediatek.com: Hi liu, > From: Neal Liu > > For Mediatek SoCs on ARMv8 with TrustZone enabled, peripherals like > entropy sources is not accessible from normal world (linux) and > rather accessible from secure world (ATF/TEE) only. This driver aims > to provide a generic interface to ATF rng service. > > Signed-off-by: Neal Liu > --- > drivers/char/hw_random/Kconfig | 16 ++++++ > drivers/char/hw_random/Makefile | 1 + > drivers/char/hw_random/mt67xx-rng.c | 104 > +++++++++++++++++++++++++++++++++++ 3 files changed, 121 insertions(+) > create mode 100644 drivers/char/hw_random/mt67xx-rng.c > > diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig > index 25a7d8f..98751d3 100644 > --- a/drivers/char/hw_random/Kconfig > +++ b/drivers/char/hw_random/Kconfig > @@ -398,6 +398,22 @@ config HW_RANDOM_MTK > > If unsure, say Y. > > +config HW_RANDOM_MT67XX > + tristate "Mediatek MT67XX Random Number Generator support" > + depends on HW_RANDOM > + depends on ARCH_MEDIATEK || COMPILE_TEST > + default HW_RANDOM > + help > + This driver provides kernel-side support for the Random Number > + Generator hardware found on Mediatek MT67xx SoCs. The difference > + with mtk-rng is the Random Number Generator hardware is secure > + access only. > + > + To compile this driver as a module, choose M here. the > + module will be called mt67xx-rng. > + > + If unsure, say Y. > + > config HW_RANDOM_S390 > tristate "S390 True Random Number Generator support" > depends on S390 > diff --git a/drivers/char/hw_random/Makefile > b/drivers/char/hw_random/Makefile index 7c9ef4a..4be95ab 100644 > --- a/drivers/char/hw_random/Makefile > +++ b/drivers/char/hw_random/Makefile > @@ -36,6 +36,7 @@ obj-$(CONFIG_HW_RANDOM_PIC32) += pic32-rng.o > obj-$(CONFIG_HW_RANDOM_MESON) += meson-rng.o > obj-$(CONFIG_HW_RANDOM_CAVIUM) += cavium-rng.o cavium-rng-vf.o > obj-$(CONFIG_HW_RANDOM_MTK) += mtk-rng.o > +obj-$(CONFIG_HW_RANDOM_MT67XX) += mt67xx-rng.o > obj-$(CONFIG_HW_RANDOM_S390) += s390-trng.o > obj-$(CONFIG_HW_RANDOM_KEYSTONE) += ks-sa-rng.o > obj-$(CONFIG_HW_RANDOM_OPTEE) += optee-rng.o > diff --git a/drivers/char/hw_random/mt67xx-rng.c > b/drivers/char/hw_random/mt67xx-rng.c new file mode 100644 > index 0000000..e70cbbe > --- /dev/null > +++ b/drivers/char/hw_random/mt67xx-rng.c > @@ -0,0 +1,104 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (C) 2019 MediaTek Inc. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define PFX KBUILD_MODNAME ": " > +#define MT67XX_RNG_MAGIC 0x74726e67 > +#define SMC_RET_NUM 4 > + > +struct mt67xx_rng_priv { > + struct hwrng rng; > +}; > + > + > +static void __rng_sec_read(uint32_t *val) > +{ > + struct arm_smccc_res res; > + > + arm_smccc_smc(MTK_SIP_KERNEL_GET_RND, > + MT67XX_RNG_MAGIC, 0, 0, 0, 0, 0, 0, &res); > + > + val[0] = res.a0; > + val[1] = res.a1; > + val[2] = res.a2; > + val[3] = res.a3; > +} > + > +static int mt67xx_rng_read(struct hwrng *rng, void *buf, size_t max, bool > wait) +{ > + int i, retval = 0; > + uint32_t val[4] = {0}; > + size_t get_rnd_size = sizeof(u32) * SMC_RET_NUM; > + > + if (!buf) { > + pr_err("%s, buf is NULL\n", __func__); > + return -EFAULT; > + } > + > + while (max >= get_rnd_size) { > + __rng_sec_read(val); > + > + for (i = 0; i < SMC_RET_NUM; i++) { > + *(u32 *)buf = val[i]; I am not sure this cast is right - or how is it guaranteed that buf is word- aligned? > + buf += sizeof(u32); > + } > + > + retval += get_rnd_size; > + max -= get_rnd_size; > + } > + > + return retval; > +} > + > +static int mt67xx_rng_probe(struct platform_device *pdev) > +{ > + int ret; > + struct mt67xx_rng_priv *priv; > + > + pr_info(PFX "driver registered\n"); > + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + > + priv->rng.name = KBUILD_MODNAME; > + priv->rng.read = mt67xx_rng_read; > + priv->rng.priv = (unsigned long)&pdev->dev; > + priv->rng.quality = 900; > + > + ret = devm_hwrng_register(&pdev->dev, &priv->rng); > + if (ret) { > + dev_err(&pdev->dev, "failed to register rng device: %d\n", ret); > + return ret; > + } > + > + return 0; > +} > + > +static const struct of_device_id mt67xx_rng_match[] = { > + { .compatible = "mediatek,mt67xx-rng", }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, mt67xx_rng_match); > + > +static struct platform_driver mt67xx_rng_driver = { > + .probe = mt67xx_rng_probe, > + .driver = { > + .name = KBUILD_MODNAME, > + .owner = THIS_MODULE, > + .of_match_table = mt67xx_rng_match, > + }, > +}; > + > +module_platform_driver(mt67xx_rng_driver); > + > +MODULE_DESCRIPTION("Mediatek MT67XX Random Number Generator Driver"); > +MODULE_AUTHOR("Neal Liu "); > +MODULE_LICENSE("GPL"); Ciao Stephan