From nobody Thu Dec 5 02:11:27 2024 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6E301186616; Tue, 3 Dec 2024 04:20:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.168.131 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733199627; cv=none; b=UBCQR0j1Q7atybXBwJF2Nw0rWqS1GfC5dhn+T/TaUYaZSpLoszjlPZc7TqcmzRqsnx6SJ/9xYV19i9DoCgCVMNGpftKSPWztFuY+zNxtLTq4EcVWJnSTV5+b4FKLpBa0dV1SfGotXekTCWdCeu0EGtspRfda/nsjvXwBiMK1YUo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733199627; c=relaxed/simple; bh=6ooM/9AY9xoHRBcOk7ycakkouxWVLDV98VBpDCj+F2k=; h=From:Date:Subject:MIME-Version:Content-Type:Message-ID:References: In-Reply-To:To:CC; b=tIoqcBR8KOa2tozQNopX4Ld2JVYlDTwVvo/XI00KPpV2kwRv9JTgG8HM6gHw9I4bxYmZKqdtpbsK5dbTxltEIjKs8pa/dy+Sinkhgnezx3q4ePv7aYKwhRgBSpGNQYT/TtlbP+30OhNEm9q9sYHexDOpxivhBuhAgNvhPy/VFRY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com; spf=pass smtp.mailfrom=quicinc.com; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b=kK2GnW7t; arc=none smtp.client-ip=205.220.168.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=quicinc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b="kK2GnW7t" Received: from pps.filterd (m0279867.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 4B2JjaPl009592; Tue, 3 Dec 2024 04:20:09 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=qcppdkim1; bh= nJ8oUk0DjJmQHwnQTgTBlinyuDwrdPECWWpX6XK+l/Q=; b=kK2GnW7t/OUg+a79 iQtwfyd1lHO7fGjal+vJ+xGK13rMRVgy3MhP+dqFgwAsEBNkW7v4w4d3EwhrQNyw Njd6j3/0UjFij7sA6jy6k28//criU/LZxvDy+ru/lUjZVgOQN36gLxRH3DHJnkc9 p4yfRFsUA5nnZqZd4fzjY1ebeO+Wt6caEKnTQZslIC3F9cUQBhPeIfejeyNydOO1 B1yH0mCBhtqbwoOdZbYgDC91/Fhxf1qSTpcGMyPkhZ0nXy+1RPfi/EgOsffDC7Xf mhSQ6coRPE8BvE6d0Di/uOR2BoIM0kCHf/J5YeG7fBaTgpUUptV/zGkkUyiXe0zy B295tg== Received: from nasanppmta05.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 437rdeeycg-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 03 Dec 2024 04:20:09 +0000 (GMT) Received: from nasanex01b.na.qualcomm.com (nasanex01b.na.qualcomm.com [10.46.141.250]) by NASANPPMTA05.qualcomm.com (8.18.1.2/8.18.1.2) with ESMTPS id 4B34K8xw024278 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 3 Dec 2024 04:20:08 GMT Received: from hu-azarrabi-lv.qualcomm.com (10.49.16.6) by nasanex01b.na.qualcomm.com (10.46.141.250) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.9; Mon, 2 Dec 2024 20:20:07 -0800 From: Amirreza Zarrabi Date: Mon, 2 Dec 2024 20:19:26 -0800 Subject: [PATCH 10/10] Documentation: tee: Add Qualcomm TEE driver Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-ID: <20241202-qcom-tee-using-tee-ss-without-mem-obj-v1-10-f502ef01e016@quicinc.com> References: <20241202-qcom-tee-using-tee-ss-without-mem-obj-v1-0-f502ef01e016@quicinc.com> In-Reply-To: <20241202-qcom-tee-using-tee-ss-without-mem-obj-v1-0-f502ef01e016@quicinc.com> To: Jens Wiklander , Sumit Garg , Bjorn Andersson , "Konrad Dybcio" , Rob Herring , "Krzysztof Kozlowski" , Conor Dooley , "Bartosz Golaszewski" , Srinivas Kandagatla CC: , , , , , Amirreza Zarrabi X-Mailer: b4 0.13.0 X-ClientProxiedBy: nalasex01c.na.qualcomm.com (10.47.97.35) To nasanex01b.na.qualcomm.com (10.46.141.250) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: iM7jLcEG1YVF7CY-ICZHAjpc1FI2Vv0o X-Proofpoint-GUID: iM7jLcEG1YVF7CY-ICZHAjpc1FI2Vv0o X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.680,FMLib:17.12.60.29 definitions=2024-09-06_09,2024-09-06_01,2024-09-02_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 mlxscore=0 adultscore=0 malwarescore=0 mlxlogscore=999 phishscore=0 suspectscore=0 impostorscore=0 clxscore=1011 lowpriorityscore=0 bulkscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2411120000 definitions=main-2412030034 Add documentation for the Qualcomm TEE driver. Signed-off-by: Amirreza Zarrabi --- Documentation/tee/index.rst | 1 + Documentation/tee/qtee.rst | 143 ++++++++++++++++++++++++++++++++++++++++= ++++ 2 files changed, 144 insertions(+) diff --git a/Documentation/tee/index.rst b/Documentation/tee/index.rst index 4be6e69d7837..62afb7ee9b52 100644 --- a/Documentation/tee/index.rst +++ b/Documentation/tee/index.rst @@ -11,6 +11,7 @@ TEE Subsystem op-tee amd-tee ts-tee + qtee =20 .. only:: subproject and html =20 diff --git a/Documentation/tee/qtee.rst b/Documentation/tee/qtee.rst new file mode 100644 index 000000000000..3185af2c2b2b --- /dev/null +++ b/Documentation/tee/qtee.rst @@ -0,0 +1,143 @@ +.. SPDX-License-Identifier: GPL-2.0 + +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D +QTEE (Qualcomm Trusted Execution Environment) +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D + +The QTEE driver handle communication with Qualcomm TEE [1]. + +Lowest level of communication with QTEE builds on ARM SMC Calling Conventi= on +(SMCCC) [2], which is the foundation for QTEE's Secure Channel Manager (SC= M) [3] +used internally by the driver [4]. + +In a QTEE-based system, services are represented as objects with series of +operations that can be called to produce results, including other objects.= When +an object is hosted within QTEE, executing its operations is referred to a= s direct +invocation. QTEE can invoke objects hosted in the kernel or userspace usin= g a +method known as callback requests. + +The SCM provides two functions for object invocation and callback request: + +- QCOM_SCM_SMCINVOKE_INVOKE for direct invocation. It can return either a = result or a callback request. +- QCOM_SCM_SMCINVOKE_CB_RSP submits a response for a previous callback req= uest. + +The QTEE Transport Message [5] is stacked on top of SCM driver functions. + +A message consists of two buffers shared with QTEE, inbound and outbound b= uffers. +The inbound buffer is used for direct invocation and the outbound buffer i= s used +to make callback request. This picture shows the contents of a QTEE transp= ort message:: + + +---------------------+ + | v + +-----------------+-------+-------+------+--------------------------+ + | qcom_tee_msg_ |object | buffer | | + | object_invoke | id | offset, size | | = (inbound buffer) + +-----------------+-------+--------------+--------------------------+ + <---- header -----><---- arguments ------><- in/out buffer payload -> + + +-----------+ + | v + +-----------------+-------+-------+------+----------------------+ + | qcom_tee_msg_ |object | buffer | | + | callback | id | offset, size | | (out= bound buffer) + +-----------------+-------+--------------+----------------------+ + +Each buffer is started with a header and array of arguments. + +QTEE Transport Message supports four types of arguments: + +- Input object is an object parameter to the current invocation or callbac= k request +- Output object is an object parameter from the current invocation or call= back request +- Input buffer is (offset, size) pair to the inbound or outbound region to= store parameter to the current invocation or callback request +- Output buffer is (offset, size) pair to the inbound or outbound region t= o store parameter from the current invocation or callback request + +The QTEE driver offers the qcom_tee_object, which represents an object wit= hin both +QTEE and the kernel. To access any service in QTEE, client needs to invoke= an +instance of this object. Any structure intended to represent a service for= export +to QTEE should include an instance of qcom_tee_object:: + + struct driver_service { + struct qcom_tee_object object; + ... + }; + + #define to_driver_service_object(o) container_of((o), struct driver_servi= ce, object) + + static int driver_service_dispatch(struct qcom_tee_object *object, u32 op, + struct qcom_tee_arg *args) + { + struct driver_service *so =3D to_driver_service_object(object); + + switch(op) { + case OBJECT_OP1: + ... + break; + default: + return -EINVAL; + } + } + + static void driver_service_object_release(struct si_object *object) + { + struct driver_service *so =3D to_driver_service_object(object); + kfree(so); + } + + struct si_object_operations driver_service_ops =3D { + .release =3D driver_service_object_release; + .dispatch =3D driver_service_dispatch; + }; + + void service_init(void) + { + struct driver_service *so =3D kzalloc(sizeof(*so), GFP_KERNEL); + + /* Initialize so->object as a callback object. */ + qcom_tee_object_user_init(&so->object, QCOM_TEE_OBJECT_TYPE_CB_OBJECT, + &driver_service_ops, "driver_service_object"); + + /* Invoke a QTEE object and pass/register 'so->object' with QTEE. */ + ... + } + module_init(service_init); + +The QTEE driver utilizes qcom_tee_object to encapsulate userspace objects.= When a +callback request is made, it translates into calling the dispatch callback= . For +userspace objects, this is converted into requests accessible to callback = servers +and available through generic TEE API IOCTLs. + +Picture of the relationship between the different components in the QTEE +architecture:: + + User space Kernel Secure world + ~~~~~~~~~~ ~~~~~~ ~~~~~~~~~~~~ + +--------+ +----------+ +-------------= -+ + | Client | |callback | | Trusted = | + +--------+ |server | | Application = | + /\ +----------+ +-------------= -+ + || +----------+ /\ /\ + || |callback | || || + || |server | || \/ + || +----------+ || +-------------= -+ + \/ /\ || | TEE Internal= | + +-------+ || || | API = | + | TEE | || || +--------+--------+ +-------------= -+ + | Client| || || | TEE | QTEE | | QTEE = | + | API | \/ \/ | subsys | driver | | Trusted OS = | + +-------+----------------+----+-------+----+-------------+-------------= -+ + | Generic TEE API | | QTEE MSG = | + | IOCTL (TEE_IOC_*) | | SMCCC (QCOM_SCM_SMCINVOKE_*) = | + +-----------------------------+ +--------------------------------= -+ + +References +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D + +[1] https://docs.qualcomm.com/bundle/publicresource/topics/80-70015-11/qua= lcomm-trusted-execution-environment.html + +[2] http://infocenter.arm.com/help/topic/com.arm.doc.den0028a/index.html + +[3] drivers/firmware/qcom/qcom_scm.c + +[4] /local/mnt/workspace/Linux/drivers/tee/qcomtee/qcom_scm.c + +[5] drivers/tee/qcomtee/qcomtee_msg.h \ No newline at end of file --=20 2.34.1