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 0F41BD3B7EA for ; Tue, 9 Dec 2025 11:03:10 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id CA38910E513; Tue, 9 Dec 2025 11:03:09 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="XTn1Nq82"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.14]) by gabe.freedesktop.org (Postfix) with ESMTPS id BB5B710E510; Tue, 9 Dec 2025 11:03:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1765278188; x=1796814188; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version:content-transfer-encoding; bh=2KcHTrM76uUY1TcCooo0dfx9HS5AmZEv1e7RejcwORg=; b=XTn1Nq82ITGpgEyO5B7ZBi+MiNt0QdHC+uDD6UU/hBBMpxPauo9FRbbR DIFZEehKNDLPEo4GSyuy6VYvSVS5PmkoMT++Mdnj2TEdFbO72ZVsjuX7x W9CMNIXkoXWmmdTar8EF1Th8nMIqFNaefgXQCLU2A5WfOtGAR01V/xJTg NjvLlw+FeOhZiQXIOyr2fFkygNy1TAlQ8C4qQQvs50GdYspRxoyjLL9i+ kmDPFfecV3Ovh+A2TGqwWVfz2lgEnhP9rFXbdyp9ysx0BR/smtrf8Vgxi jGfbCCx+HO3o+Mb88AdZa5SMUG4ItNtW5NS/NXvqAKarpo31QjVq5tSBm w==; X-CSE-ConnectionGUID: 8N518ooQQdaEDpI4PPwsBQ== X-CSE-MsgGUID: Mo86Jm82TueyhWrksEkdQQ== X-IronPort-AV: E=McAfee;i="6800,10657,11636"; a="71088469" X-IronPort-AV: E=Sophos;i="6.20,261,1758610800"; d="scan'208";a="71088469" Received: from fmviesa009.fm.intel.com ([10.60.135.149]) by orvoesa106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Dec 2025 03:03:07 -0800 X-CSE-ConnectionGUID: /FPZ+t4lTNWY0bH3gD19iw== X-CSE-MsgGUID: PXKotNJKQSCZut8Y/LwQDw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.20,261,1758610800"; d="scan'208";a="196658303" Received: from mwiniars-mobl.ger.corp.intel.com (HELO localhost) ([10.245.246.154]) by fmviesa009-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Dec 2025 03:03:06 -0800 From: Jani Nikula To: Ville Syrjala , intel-gfx@lists.freedesktop.org Cc: intel-xe@lists.freedesktop.org Subject: Re: [PATCH 19/19] drm/i915: Document the GMCH_CTRL register a bit In-Reply-To: <20251208182637.334-20-ville.syrjala@linux.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20251208182637.334-1-ville.syrjala@linux.intel.com> <20251208182637.334-20-ville.syrjala@linux.intel.com> Date: Tue, 09 Dec 2025 13:03:02 +0200 Message-ID: <29ba4ddecf7d907c26e19da8ad5f585aabebd9c8@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" On Mon, 08 Dec 2025, Ville Syrjala wrote: > From: Ville Syrj=C3=A4l=C3=A4 > > The actual GMCH_CRTL lives in the host bridge aka. device 0), Superfluous ) or missing (. > but device 2 has a read-only mirror on i85x/i865+. Docuemnent *Document > that fact. > > Also remove the ancient tales about where the defines are used. > Those haven't been true in a long time. > > Signed-off-by: Ville Syrj=C3=A4l=C3=A4 Reviewed-by: Jani Nikula > --- > include/drm/intel/i915_drm.h | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/include/drm/intel/i915_drm.h b/include/drm/intel/i915_drm.h > index c633ce62f2bf..8eee23f94e26 100644 > --- a/include/drm/intel/i915_drm.h > +++ b/include/drm/intel/i915_drm.h > @@ -39,11 +39,11 @@ bool i915_gpu_turbo_disable(void); > extern struct resource intel_graphics_stolen_res; >=20=20 > /* > - * The Bridge device's PCI config space has information about the > - * fb aperture size and the amount of pre-reserved memory. > - * This is all handled in the intel-gtt.ko module. i915.ko only > - * cares about the vga bit for the vga arbiter. > + * The Bridge device's (device 0) PCI config space has information > + * about the fb aperture size and the amount of pre-reserved memory. > */ > + > +/* device 2 has a read-only mirror */ > #define SNB_GMCH_CTRL 0x50 > #define SNB_GMCH_GGMS_SHIFT 8 /* GTT Graphics Memory Size */ > #define SNB_GMCH_GGMS_MASK 0x3 > @@ -54,6 +54,7 @@ extern struct resource intel_graphics_stolen_res; > #define BDW_GMCH_GMS_SHIFT 8 > #define BDW_GMCH_GMS_MASK 0xff >=20=20 > +/* device 2 has a read-only mirror from i85x/i865 onwards */ > #define I830_GMCH_CTRL 0x52 > #define I830_GMCH_GMS_MASK (0x7 << 4) > #define I830_GMCH_GMS_LOCAL (0x1 << 4) --=20 Jani Nikula, Intel