From patchwork Mon May 27 08:38:46 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Neal Liu X-Patchwork-Id: 10962331 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5F96176 for ; Mon, 27 May 2019 08:40:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4CEE22894B for ; Mon, 27 May 2019 08:40:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3F23B28998; Mon, 27 May 2019 08:40:21 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id CC1832894B for ; Mon, 27 May 2019 08:40:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=bm+dj2QTGqMlwpvUIBwvddcLJXA0MVwXCCoEbBK7+B0=; b=eMfvv3l+n4lX8/ DXuY6Yt9IXTDV1CkrpjxHzAHRSTja47Q9P0n0m58eAzrguPdH7dGZQdzDUZ6yP5jSHOL6REmFymVe NGWd/UYQCbRrp2ojL4SMSKtOaOX1eVM+hX0jkZw201sYJm48F0zSk3lo3cU1rCSdURQwRCDZvszS1 BkTcJOeu/+eEf3QthYISubhcR9Uk9ugkHGAekYhToUA9Kuw8oMKsozkPZzBaqPS0xyA28p1cNuDcz xMv8AtueSoJM5K5DIvgc+RVF9AwMgpRWPUF0Obp0WaIX568izwkNg58py/tLsHMZzgMhqvGIVo8vr 2dkHZ7q5HVMI7IYIlWWw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hVBB2-0003Ek-Mi; Mon, 27 May 2019 08:40:16 +0000 Received: from mailgw02.mediatek.com ([216.200.240.185]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hVBAK-0001My-GW; Mon, 27 May 2019 08:39:42 +0000 X-UUID: 2c2e308801064927a56cb89cd4d566a9-20190527 X-UUID: 2c2e308801064927a56cb89cd4d566a9-20190527 Received: from mtkcas68.mediatek.inc [(172.29.94.19)] by mailgw02.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLS) with ESMTP id 413745007; Mon, 27 May 2019 00:39:23 -0800 Received: from MTKMBS01N2.mediatek.inc (172.21.101.79) by MTKMBS62N1.mediatek.inc (172.29.193.41) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Mon, 27 May 2019 01:39:23 -0700 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs01n2.mediatek.inc (172.21.101.79) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Mon, 27 May 2019 16:39:08 +0800 Received: from mtkswgap22.mediatek.inc (172.21.77.33) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Mon, 27 May 2019 16:39:08 +0800 From: Neal Liu To: Matt Mackall , Herbert Xu , Rob Herring , Mark Rutland , Matthias Brugger , Sean Wang Subject: [PATCH v2 3/3] hwrng: add mtk-sec-rng driver Date: Mon, 27 May 2019 16:38:46 +0800 Message-ID: <1558946326-13630-4-git-send-email-neal.liu@mediatek.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1558946326-13630-1-git-send-email-neal.liu@mediatek.com> References: <1558946326-13630-1-git-send-email-neal.liu@mediatek.com> MIME-Version: 1.0 X-TM-SNTS-SMTP: BD4B105A6E092554A06C671E9FEB9F64EE7E7C79F5631132485CF7A2508A38002000:8 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190527_013933_324018_56B28684 X-CRM114-Status: GOOD ( 15.94 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, wsd_upstream@mediatek.com, lkml , Crystal Guo , linux-mediatek@lists.infradead.org, linux-crypto@vger.kernel.org, Neal Liu , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP 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/mtk-sec-rng.c | 97 ++++++++++++++++++++++++++++++++++ 3 files changed, 114 insertions(+) create mode 100644 drivers/char/hw_random/mtk-sec-rng.c diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig index 25a7d8f..6c82a3b 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_MTK_SEC + tristate "MediaTek Security 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 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 mtk-sec-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..0ae4993 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-$(CONFIG_HW_RANDOM_MTK_SEC) += mtk-sec-rng.o obj-$(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/mtk-sec-rng.c b/drivers/char/hw_random/mtk-sec-rng.c new file mode 100644 index 0000000..4c6e5bf --- /dev/null +++ b/drivers/char/hw_random/mtk-sec-rng.c @@ -0,0 +1,97 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 MediaTek Inc. + */ + +#include +#include +#include +#include +#include +#include + +#define MT67XX_RNG_MAGIC 0x74726e67 +#define SMC_RET_NUM 4 +#define MTK_SEC_RND_SIZE (sizeof(u32) * SMC_RET_NUM) + +struct mtk_sec_rng_priv { + struct hwrng rng; +}; + +static void mtk_sec_get_rnd(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 mtk_sec_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait) +{ + size_t get_rnd_size = MTK_SEC_RND_SIZE; + u32 val[4] = {0}; + int i, retval = 0; + + while (max >= get_rnd_size) { + mtk_sec_get_rnd(val); + + for (i = 0; i < SMC_RET_NUM; i++) { + *(u32 *)buf = val[i]; + buf += sizeof(u32); + } + + retval += get_rnd_size; + max -= get_rnd_size; + } + + return retval; +} + +static int mtk_sec_rng_probe(struct platform_device *pdev) +{ + struct mtk_sec_rng_priv *priv; + int ret; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->rng.name = pdev->name; + priv->rng.read = mtk_sec_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 mtk_sec_rng_match[] = { + { .compatible = "mediatek,mtk-sec-rng", }, + {} +}; +MODULE_DEVICE_TABLE(of, mtk_sec_rng_match); + +static struct platform_driver mtk_sec_rng_driver = { + .probe = mtk_sec_rng_probe, + .driver = { + .name = KBUILD_MODNAME, + .owner = THIS_MODULE, + .of_match_table = mtk_sec_rng_match, + }, +}; + +module_platform_driver(mtk_sec_rng_driver); + +MODULE_DESCRIPTION("MediaTek Security Random Number Generator Driver"); +MODULE_AUTHOR("Neal Liu "); +MODULE_LICENSE("GPL");