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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 6DDEDC43216 for ; Thu, 26 Aug 2021 12:30:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4970E610CA for ; Thu, 26 Aug 2021 12:30:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241041AbhHZMba (ORCPT ); Thu, 26 Aug 2021 08:31:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60122 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234495AbhHZMba (ORCPT ); Thu, 26 Aug 2021 08:31:30 -0400 Received: from mail-lf1-x12d.google.com (mail-lf1-x12d.google.com [IPv6:2a00:1450:4864:20::12d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A4033C061757 for ; Thu, 26 Aug 2021 05:30:42 -0700 (PDT) Received: by mail-lf1-x12d.google.com with SMTP id i9so6442157lfg.10 for ; Thu, 26 Aug 2021 05:30:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=GhgYsmvqrAxJX0LtPmrYeEXggYv/fhoAephchEquNLc=; b=SiDDwqW32wUAav4VM8KMQ9B6zVIWZUVIv8hwgF0PUZM6+DGTErVzzLpW1QVyZSthdJ xDCc4TxDcP4XAVEhblYC1/AZA+NQz1/quHZ5jKMYnhRrk2RFxGDEBAR8WFO+qPjU8LGm Vz07x9i9zOh6Mr/J2dy/0Q/q+cJ1BBcyOAyKNfr5VVqulgD8ONj21JQPPbXP7UNszXRo rnvXdeMIuCmXsqqxp/5j38Q+YPr/FctuEIrowQwltE74+7XgEyzbh0gEvFW5NMoQG04U EWudR3uMOWWZhdcrHurLQV4qtxDa86g7LQCU0Ou+FFwmVGZsxbDZKabPS5MXGzx+RAyE CmuQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=GhgYsmvqrAxJX0LtPmrYeEXggYv/fhoAephchEquNLc=; b=ieTjYWqjveyaevXu5FsmCYLrrhAC6IUWWoLPwBmlVo7KHf7oRd6VxsbIb6Rhp0tndT cHDmVA1t/VN7m/UavCWRXEsYeREhacsYrSSMlDk5nAe6fENKCOwZ66UnC0RE32uG6b3p saY1uTOVidXMT4PWu8VFtao3eFUU694gvZZtprSjXq+F3n2kmuz9o9UrTSv4+yroIXei 7EXDFkSlgaTiBK5aoCKFyzqSNLkfFkkspfb97i4ZiMfLAg1ZGWcpDgI8Iq7dGMxjYbPh wB4k+wSlIkB8xvjmoFCkL0W67I++xtL/PdwLIHXiyNnO49lfnHnios91xG0gkt7ug8tl snMQ== X-Gm-Message-State: AOAM531b2dxU2dsqnA33041LiS2PkYIGvKFOAAdGrWTV/VQOlGQJTPPI Ct6lLKOWOpceCQpamB0yOauS6g== X-Google-Smtp-Source: ABdhPJzXMNNF/bi1HIJqWX3/mI79XcU/bUU6dSehJCcvs2LOiH6i8Tz11P+VEt73eqlvd3LlKmse5A== X-Received: by 2002:a19:c148:: with SMTP id r69mr487638lff.281.1629981041039; Thu, 26 Aug 2021 05:30:41 -0700 (PDT) Received: from jade.ideon.se ([85.235.10.227]) by smtp.gmail.com with ESMTPSA id j21sm332283ljh.87.2021.08.26.05.30.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 26 Aug 2021 05:30:40 -0700 (PDT) From: Jens Wiklander To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, op-tee@lists.trustedfirmware.org, devicetree@vger.kernel.org, linux-doc@vger.kernel.org Cc: Jerome Forissier , Etienne Carriere , Sumit Garg , Vincent Guittot , Rob Herring , Jonathan Corbet , Ard Biesheuvel , Marc Zyngier , Jens Wiklander Subject: [PATCH v5 1/6] docs: staging/tee.rst: add a section on OP-TEE notifications Date: Thu, 26 Aug 2021 14:30:27 +0200 Message-Id: <20210826123032.1732926-2-jens.wiklander@linaro.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210826123032.1732926-1-jens.wiklander@linaro.org> References: <20210826123032.1732926-1-jens.wiklander@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Adds a section on notifications used by OP-TEE, synchronous and asynchronous. Acked-by: Marc Zyngier Signed-off-by: Jens Wiklander --- Documentation/staging/tee.rst | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/Documentation/staging/tee.rst b/Documentation/staging/tee.rst index 4d4b5f889603..3c63d8dcd61e 100644 --- a/Documentation/staging/tee.rst +++ b/Documentation/staging/tee.rst @@ -184,6 +184,36 @@ order to support device enumeration. In other words, OP-TEE driver invokes this application to retrieve a list of Trusted Applications which can be registered as devices on the TEE bus. +OP-TEE notifications +-------------------- + +There are two kinds of notifications that secure world can use to make +normal world aware of some event. + +1. Synchronous notifications delivered with ``OPTEE_RPC_CMD_NOTIFICATION`` + using the ``OPTEE_RPC_NOTIFICATION_SEND`` parameter. +2. Asynchronous notifications delivered with a combination of a non-secure + edge-triggered interrupt and a fast call from the non-secure interrupt + handler. + +Synchronous notifications are limited by depending on RPC for delivery, +this is only usable when secure world is entered with a yielding call via +``OPTEE_SMC_CALL_WITH_ARG``. This excludes such notifications from secure +world interrupt handlers. + +An asynchronous notification is delivered via a non-secure edge-triggered +interrupt to an interrupt handler registered in the OP-TEE driver. The +actual notification value are retrieved with the fast call +``OPTEE_SMC_GET_ASYNC_NOTIF_VALUE``. Note that one interrupt can represent +multiple notifications. + +One notification value ``OPTEE_SMC_ASYNC_NOTIF_VALUE_DO_BOTTOM_HALF`` has a +special meaning. When this value is received it means that normal world is +supposed to make a yielding call ``OPTEE_MSG_CMD_DO_BOTTOM_HALF``. This +call is done from the thread assisting the interrupt handler. This is a +building block for OP-TEE OS in secure world to implement the top half and +bottom half style of device drivers. + AMD-TEE driver ============== -- 2.31.1