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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 33D4CCFD377 for ; Tue, 25 Nov 2025 10:26:54 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BF78610E3A9; Tue, 25 Nov 2025 10:26:53 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="MfNzVu19"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.18]) by gabe.freedesktop.org (Postfix) with ESMTPS id E180910E3A9 for ; Tue, 25 Nov 2025 10:26:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1764066412; x=1795602412; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=M4ryqwRLQtgqqHT7/6qoXeIvgW9pJC0R1Y1Al3BtVdI=; b=MfNzVu19qKDHTLy9vLa53mI22Hf3ZMIxGzrHKbPZ7vWChCOqimJgVCT5 ds93eWiNj+Zy2DXrjwgX3D57GrCdYrAXeQgt8QSjPeRACllS1zwxCECQb lVYUt86rVFTRZ4wC4Q+Ygu8Vw3GfZI8vnGO/BM0XswwiGA4VJQytqiWuz oayPAtVSwU/PPnZygSJBWc9mHRXA6Zb4+5clvD7sORLZPMhZsgvGB1Uhk jqo9ZCefLfIud8QMaYrQ7iy6S0yP3+ufVL+T32YGKD4i8uPOp354cKXFF Q1F9BUREOBp0t4OptWjqAltV2RHxFMel5LPYHBlbSLvwLXvIEYLHut43V A==; X-CSE-ConnectionGUID: lYMu+pfHRR238YS7T6NnfA== X-CSE-MsgGUID: mQK5BjPBTNa3mLJYZYpVaQ== X-IronPort-AV: E=McAfee;i="6800,10657,11623"; a="65265097" X-IronPort-AV: E=Sophos;i="6.20,225,1758610800"; d="scan'208";a="65265097" Received: from orviesa003.jf.intel.com ([10.64.159.143]) by fmvoesa112.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Nov 2025 02:26:51 -0800 X-CSE-ConnectionGUID: Yt0BW1WrTdCujYgcmsodmg== X-CSE-MsgGUID: 8GEg0aqASNedzGfcTx+yZw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.20,225,1758610800"; d="scan'208";a="196766232" Received: from ettammin-desk.ger.corp.intel.com (HELO localhost) ([10.245.246.213]) by ORVIESA003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Nov 2025 02:26:49 -0800 From: Jani Nikula To: Daniele Ceraolo Spurio , intel-gfx@lists.freedesktop.org Cc: gregkh@linuxfoundation.org, Daniele Ceraolo Spurio , Alexander Usyskin Subject: Re: [PATCH v3 1/2] mei: me: Export the PCI ID list In-Reply-To: <20251114201431.1135031-5-daniele.ceraolospurio@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20251114201431.1135031-4-daniele.ceraolospurio@intel.com> <20251114201431.1135031-5-daniele.ceraolospurio@intel.com> Date: Tue, 25 Nov 2025 12:26:46 +0200 Message-ID: <632d00475a9dc4e878d7145834a70028ab298f95@intel.com> MIME-Version: 1.0 Content-Type: text/plain 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" On Fri, 14 Nov 2025, Daniele Ceraolo Spurio wrote: > The intel GFX drivers (i915/xe) interface with the ME device for some of > their features (e.g. PXP, HDCP) via the component interface. Given that > the ME device can be hidden by BIOS/Coreboot, the GFX drivers need a > way to check if the device is available before attempting to bind the > component, otherwise they'll go ahead and initialize features that will > never work. > The simplest way to check if the ME device is available is to check the > available devices against the PCI ID list of the mei_me driver. To avoid > duplication, this patch exports the list, so that it can be used directly > from the GFX drivers. > > Signed-off-by: Daniele Ceraolo Spurio > Cc: Alexander Usyskin > Cc: Greg Kroah-Hartman > --- > drivers/misc/mei/pci-me.c | 12 +++++++++++- > include/linux/mei_me.h | 15 +++++++++++++++ > 2 files changed, 26 insertions(+), 1 deletion(-) > create mode 100644 include/linux/mei_me.h > > diff --git a/drivers/misc/mei/pci-me.c b/drivers/misc/mei/pci-me.c > index b017ff29dbd1..632756f9da66 100644 > --- a/drivers/misc/mei/pci-me.c > +++ b/drivers/misc/mei/pci-me.c > @@ -18,6 +18,7 @@ > #include > > #include > +#include > > #include "mei_dev.h" > #include "client.h" > @@ -25,7 +26,7 @@ > #include "hw-me.h" > > /* mei_pci_tbl - PCI Device ID Table */ > -static const struct pci_device_id mei_me_pci_tbl[] = { > +const struct pci_device_id mei_me_pci_tbl[] = { > {MEI_PCI_DEVICE(MEI_DEV_ID_82946GZ, MEI_ME_ICH_CFG)}, > {MEI_PCI_DEVICE(MEI_DEV_ID_82G35, MEI_ME_ICH_CFG)}, > {MEI_PCI_DEVICE(MEI_DEV_ID_82Q965, MEI_ME_ICH_CFG)}, > @@ -135,6 +136,15 @@ static const struct pci_device_id mei_me_pci_tbl[] = { > > MODULE_DEVICE_TABLE(pci, mei_me_pci_tbl); > > +/* > + * Other drivers (e.g., i915, xe) interface with the ME device for some of their > + * features (e.g., PXP, HDCP). However, the ME device can be unplugged via the > + * pci subsystem or hidden by BIOS/coreboot, so those drivers might want to > + * check if the device is available before initializing those features. To > + * allow them to perform such a check, we export the list of ME device IDs. > + */ > +EXPORT_SYMBOL_GPL(mei_me_pci_tbl); Data is not an interface. Please add an exported helper function (with a sensible stub for CONFIG_INTEL_MEI_ME=n) and everything becomes much cleaner both mei and i915 side. BR, Jani. > + > #ifdef CONFIG_PM > static inline void mei_me_set_pm_domain(struct mei_device *dev); > static inline void mei_me_unset_pm_domain(struct mei_device *dev); > diff --git a/include/linux/mei_me.h b/include/linux/mei_me.h > new file mode 100644 > index 000000000000..48fd913a3d95 > --- /dev/null > +++ b/include/linux/mei_me.h > @@ -0,0 +1,15 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Copyright (c) 2025, Intel Corporation. All rights reserved. > + */ > + > +#ifndef _LINUX_MEI_ME_H > +#define _LINUX_MEI_ME_H > + > +#include > + > +#if IS_ENABLED(CONFIG_INTEL_MEI_ME) > +extern const struct pci_device_id mei_me_pci_tbl[]; > +#endif > + > +#endif /* _LINUX_MEI_ME_H */ -- Jani Nikula, Intel