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=-8.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,UNPARSEABLE_RELAY, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 6B835C04A6B for ; Wed, 8 May 2019 04:00:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3578F214AE for ; Wed, 8 May 2019 04:00:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727130AbfEHEAA (ORCPT ); Wed, 8 May 2019 00:00:00 -0400 Received: from mailgw02.mediatek.com ([210.61.82.184]:23213 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1727053AbfEHD77 (ORCPT ); Tue, 7 May 2019 23:59:59 -0400 X-UUID: 856f16bd04674a6a8e3e9bb1f6e58265-20190508 X-UUID: 856f16bd04674a6a8e3e9bb1f6e58265-20190508 Received: from mtkcas09.mediatek.inc [(172.21.101.178)] by mailgw02.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 1677202790; Wed, 08 May 2019 11:59:51 +0800 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs01n1.mediatek.inc (172.21.101.68) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Wed, 8 May 2019 11:59:49 +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; Wed, 8 May 2019 11:59:49 +0800 From: To: , , , , CC: , , , , , Neal Liu Subject: [PATCH 3/3] hwrng: add mt67xx-rng driver Date: Wed, 8 May 2019 11:58:57 +0800 Message-ID: <1557287937-2410-4-git-send-email-neal.liu@mediatek.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1557287937-2410-1-git-send-email-neal.liu@mediatek.com> References: <1557287937-2410-1-git-send-email-neal.liu@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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]; + 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"); -- 1.7.9.5