From patchwork Mon May 4 09:08:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kahola, Mika" X-Patchwork-Id: 11525245 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 02833912 for ; Mon, 4 May 2020 09:08:54 +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 DE7722054F for ; Mon, 4 May 2020 09:08:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DE7722054F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 97DA289935; Mon, 4 May 2020 09:08:50 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id 1112E89935 for ; Mon, 4 May 2020 09:08:50 +0000 (UTC) IronPort-SDR: suJlqH2E/ejb2S2G+RywiCKfxDZcYMRthHP5IvR8tXExpw6zon1bWI4+QvRYxWhDZ0JMU7lRNw 9W1kcYACuVWA== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 May 2020 02:08:49 -0700 IronPort-SDR: Qid/nHcAY0rd9qs22mLTGDvKF+d/RGqN+MlkffsIWKOuE1nJbp9Dr36VUfASWGMyXzv4L+qAcX UvHbal+r+yBg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,351,1583222400"; d="scan'208";a="406416780" Received: from sorvi.fi.intel.com ([10.237.72.159]) by orsmga004.jf.intel.com with ESMTP; 04 May 2020 02:08:48 -0700 From: Mika Kahola To: dri-devel@lists.freedesktop.org Subject: [PATCH] uapi/drm/drm_fourcc.h: Note on platform specificity for format modifiers Date: Mon, 4 May 2020 12:08:43 +0300 Message-Id: <20200504090843.27074-1-mika.kahola@intel.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mika Kahola Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Make an additional note on DRM format modifiers for x and y tiling. These format modifiers are defined for BDW+ platforms and therefore definition is not valid for older gens. This is due to address swizzling for tiled surfaces is no longer used. For newer platforms main memory controller has a more effective address swizzling algorithm. Signed-off-by: Mika Kahola --- include/uapi/drm/drm_fourcc.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h index 8bc0b31597d8..3e56c24cabb6 100644 --- a/include/uapi/drm/drm_fourcc.h +++ b/include/uapi/drm/drm_fourcc.h @@ -356,7 +356,8 @@ extern "C" { * * This format is highly platforms specific and not useful for cross-driver * sharing. It exists since on a given platform it does uniquely identify the - * layout in a simple way for i915-specific userspace. + * layout in a simple way for i915-specific userspace. The format is + * ill-defined for platforms older than BDW. */ #define I915_FORMAT_MOD_X_TILED fourcc_mod_code(INTEL, 1) @@ -371,7 +372,8 @@ extern "C" { * * This format is highly platforms specific and not useful for cross-driver * sharing. It exists since on a given platform it does uniquely identify the - * layout in a simple way for i915-specific userspace. + * layout in a simple way for i915-specific userspace. The format is + * ill-defined for platforms older than BDW. */ #define I915_FORMAT_MOD_Y_TILED fourcc_mod_code(INTEL, 2)