From patchwork Mon Jun 24 07:24:12 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Neal Liu X-Patchwork-Id: 11012475 X-Patchwork-Delegate: herbert@gondor.apana.org.au 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 14B896C5 for ; Mon, 24 Jun 2019 07:24:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EDA1628832 for ; Mon, 24 Jun 2019 07:24:39 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DE1F328B49; Mon, 24 Jun 2019 07:24:39 +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=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI,UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1C85928832 for ; Mon, 24 Jun 2019 07:24:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727409AbfFXHYh (ORCPT ); Mon, 24 Jun 2019 03:24:37 -0400 Received: from mailgw01.mediatek.com ([210.61.82.183]:59104 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726719AbfFXHYh (ORCPT ); Mon, 24 Jun 2019 03:24:37 -0400 X-UUID: f99ff83372764d82ac28946816a925de-20190624 X-UUID: f99ff83372764d82ac28946816a925de-20190624 Received: from mtkmrs01.mediatek.inc [(172.21.131.159)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 176232665; Mon, 24 Jun 2019 15:24:30 +0800 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs07n1.mediatek.inc (172.21.101.16) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Mon, 24 Jun 2019 15:24:29 +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, 24 Jun 2019 15:24:28 +0800 From: Neal Liu To: Matt Mackall , Herbert Xu , Rob Herring , Mark Rutland , Matthias Brugger , Sean Wang CC: Neal Liu , Crystal Guo , , , , , , Subject: [PATCH v4 3/3] hwrng: add mtk-sec-rng driver Date: Mon, 24 Jun 2019 15:24:12 +0800 Message-ID: <1561361052-13072-4-git-send-email-neal.liu@mediatek.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1561361052-13072-1-git-send-email-neal.liu@mediatek.com> References: <1561361052-13072-1-git-send-email-neal.liu@mediatek.com> MIME-Version: 1.0 X-MTK: N Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.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..ecd2e29 --- /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) +{ + u32 val[4] = {0}; + int retval = 0; + int i; + + while (max >= MTK_SEC_RND_SIZE) { + mtk_sec_get_rnd(val); + + for (i = 0; i < SMC_RET_NUM; i++) { + *(u32 *)buf = val[i]; + buf += sizeof(u32); + } + + retval += MTK_SEC_RND_SIZE; + max -= MTK_SEC_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");