From patchwork Sat Aug 28 01:27:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniele Ceraolo Spurio X-Patchwork-Id: 12463195 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 436C8C43214 for ; Sat, 28 Aug 2021 01:30:29 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1603A60F58 for ; Sat, 28 Aug 2021 01:30:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 1603A60F58 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 36F9A6E9F6; Sat, 28 Aug 2021 01:30:12 +0000 (UTC) Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by gabe.freedesktop.org (Postfix) with ESMTPS id 3F1B26EA0A; Sat, 28 Aug 2021 01:29:52 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10089"; a="303630242" X-IronPort-AV: E=Sophos;i="5.84,358,1620716400"; d="scan'208";a="303630242" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Aug 2021 18:29:52 -0700 X-IronPort-AV: E=Sophos;i="5.84,358,1620716400"; d="scan'208";a="517537172" Received: from valcore-skull-1.fm.intel.com ([10.1.27.19]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Aug 2021 18:29:52 -0700 From: Daniele Ceraolo Spurio To: intel-gfx@lists.freedesktop.org Cc: dri-devel@lists.freedesktop.org, Daniele Ceraolo Spurio , Daniel Vetter , Rodrigo Vivi Date: Fri, 27 Aug 2021 18:27:37 -0700 Message-Id: <20210828012738.317661-17-daniele.ceraolospurio@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210828012738.317661-1-daniele.ceraolospurio@intel.com> References: <20210828012738.317661-1-daniele.ceraolospurio@intel.com> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH v7 16/17] drm/i915/pxp: add PXP documentation X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Now that all the pieces are in place we can add a description of how the feature works. Also modify the comments in struct intel_pxp into kerneldoc. Signed-off-by: Daniele Ceraolo Spurio Cc: Daniel Vetter Cc: Rodrigo Vivi --- Documentation/gpu/i915.rst | 8 ++++ drivers/gpu/drm/i915/pxp/intel_pxp.c | 28 +++++++++++++ drivers/gpu/drm/i915/pxp/intel_pxp_types.h | 47 ++++++++++++++++------ 3 files changed, 71 insertions(+), 12 deletions(-) diff --git a/Documentation/gpu/i915.rst b/Documentation/gpu/i915.rst index 204ebdaadb45..2e267ecd7651 100644 --- a/Documentation/gpu/i915.rst +++ b/Documentation/gpu/i915.rst @@ -474,6 +474,14 @@ Object Tiling IOCTLs .. kernel-doc:: drivers/gpu/drm/i915/gem/i915_gem_tiling.c :doc: buffer object tiling +Protected Objects +----------------- + +.. kernel-doc:: drivers/gpu/drm/i915/pxp/intel_pxp.c + :doc: PXP + +.. kernel-doc:: drivers/gpu/drm/i915/pxp/intel_pxp_types.h + Microcontrollers ================ diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.c b/drivers/gpu/drm/i915/pxp/intel_pxp.c index 8c73ab0f2e7c..29e011cf7139 100644 --- a/drivers/gpu/drm/i915/pxp/intel_pxp.c +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.c @@ -11,6 +11,34 @@ #include "gt/intel_context.h" #include "i915_drv.h" +/** + * DOC: PXP + * + * PXP (Protected Xe Path) is a Gen12+ feature that allows execution and + * flip to display of protected (i.e. encrypted) objects. The SW support is + * enabled via the CONFIG_DRM_I915_PXP kconfig. + * + * Some of the PXP setup operations are performed by the Management Engine, + * which is handled by the mei driver; communication between i915 and mei is + * performed via the mei_pxp component module. + * + * Objects can opt-in to PXP encryption at creation time via the + * I915_GEM_CREATE_EXT_PROTECTED_CONTENT create_ext flag. For objects to be + * correctly protected they must be used in conjunction with a context created + * with the I915_CONTEXT_PARAM_PROTECTED_CONTENT flag. See the documentation + * of those two uapi flags for details and restrictions. + * + * Protected objects are tied to a pxp session; currently we only support one + * session, which i915 manages and whose index is available in the uapi + * (I915_PROTECTED_CONTENT_DEFAULT_SESSION) for use in instructions targeting + * protected objects. + * The session is invalidated by the HW when certain events occur (e.g. + * suspend/resume). When this happens, all the objects that were used with the + * session are marked as invalid and all contexts marked as using protected + * content are banned. Any further attempt at using them in an execbuf call is + * rejected, while flips are converted to black frames. + */ + /* KCR register definitions */ #define KCR_INIT _MMIO(0x320f0) diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_types.h b/drivers/gpu/drm/i915/pxp/intel_pxp_types.h index ae24064bb57e..73ef7d1754e1 100644 --- a/drivers/gpu/drm/i915/pxp/intel_pxp_types.h +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_types.h @@ -16,42 +16,65 @@ struct intel_context; struct i915_pxp_component; +/** + * struct intel_pxp - pxp state + */ struct intel_pxp { + /** + * @pxp_component: i915_pxp_component struct of the bound mei_pxp + * module. Only set and cleared inside component bind/unbind functions, + * which are protected by &tee_mutex. + */ struct i915_pxp_component *pxp_component; + /** + * @pxp_component_added: track if the pxp component has been added. + * Set and cleared in tee init and fini functions respectively. + */ bool pxp_component_added; + /** @ce: kernel-owned context used for PXP operations */ struct intel_context *ce; - /* + /** @arb_mutex: protects arb session start */ + struct mutex arb_mutex; + /** + * @arb_is_valid: tracks arb session status. * After a teardown, the arb session can still be in play on the HW * even if the keys are gone, so we can't rely on the HW state of the * session to know if it's valid and need to track the status in SW. */ - struct mutex arb_mutex; /* protects arb session start */ bool arb_is_valid; - /* - * Keep track of which key instance we're on, so we can use it to - * determine if an object was created using the current key or a + /** + * @key_instance: tracks which key instance we're on, so we can use it + * to determine if an object was created using the current key or a * previous one. */ u32 key_instance; - struct mutex tee_mutex; /* protects the tee channel binding */ + /** @tee_mutex: protects the tee channel binding and messaging. */ + struct mutex tee_mutex; - /* - * If the HW perceives an attack on the integrity of the encryption it - * will invalidate the keys and expect SW to re-initialize the session. - * We keep track of this state to make sure we only re-start the arb - * session when required. + /** + * @hw_state_invalidated: if the HW perceives an attack on the integrity + * of the encryption it will invalidate the keys and expect SW to + * re-initialize the session. We keep track of this state to make sure + * we only re-start the arb session when required. */ bool hw_state_invalidated; + /** @irq_enabled: tracks the status of the kcr irqs */ bool irq_enabled; + /** + * @termination: tracks the status of a pending termination. Only + * re-initialized under gt->irq_lock and completed in &session_work. + */ struct completion termination; + /** @session_work: worker that manages session events. */ struct work_struct session_work; - u32 session_events; /* protected with gt->irq_lock */ + /** @session_events: pending session events, protected with gt->irq_lock. */ + u32 session_events; #define PXP_TERMINATION_REQUEST BIT(0) #define PXP_TERMINATION_COMPLETE BIT(1) #define PXP_INVAL_REQUIRED BIT(2)