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 39961C52D6F for ; Tue, 27 Aug 2024 06:43:40 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E413A10E280; Tue, 27 Aug 2024 06:43:39 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="IPcn35J+"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.16]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4CA9310E280; Tue, 27 Aug 2024 06:43:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1724741019; x=1756277019; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=4vxpAwtvtF5WGuttQiVSNF5ydNiHjjq7NEm3lzbfHWM=; b=IPcn35J+/ijADjaTl5QDrYMkS/IE+hId8vcbdQcSduq68IrD0WvlpYb5 j/Hp6S5ywfeYGPr4makcIBZB8YvRtyIdLROqgTnTC11Q1ga8fqRLVhtQb NfLxGIHMczppL2xCYblmAs8ByYeBsJHNcPXPcpEB5mJAEg/8/vMciu5bK uXKfw/nxJK+5h9RVqWXhee3aNXPXQsL7xsT1RUB3KrrY5e6mqn+Jvw4xy gKFY5gL+RysWzRotkPAPC4X4D46WyPULvqPFZqyzyAvGbz2okYi5waUNT URR6qN9Y/S0HaVy3BTgUURHjFhR2YYfKCfzE2JbBbirT7EFOMn7dwYRem Q==; X-CSE-ConnectionGUID: naA5teHiSXWmdNa9Df9ryA== X-CSE-MsgGUID: 9mj5lkPyT96TLCH8EdKrbw== X-IronPort-AV: E=McAfee;i="6700,10204,11176"; a="23324992" X-IronPort-AV: E=Sophos;i="6.10,179,1719903600"; d="scan'208";a="23324992" Received: from fmviesa001.fm.intel.com ([10.60.135.141]) by orvoesa108.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Aug 2024 23:43:38 -0700 X-CSE-ConnectionGUID: tG5FDlN0TpWF0qeiWXR+ow== X-CSE-MsgGUID: 3lnfmLvxQx+7oqSsl3S+Ww== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,179,1719903600"; d="scan'208";a="93553520" Received: from fpallare-mobl3.ger.corp.intel.com (HELO [10.245.244.6]) ([10.245.244.6]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Aug 2024 23:43:34 -0700 Message-ID: <927bdb3b-8372-4d21-b807-0f051832f6d5@linux.intel.com> Date: Tue, 27 Aug 2024 08:43:36 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 2/2] drm/xe: Align all VRAM scanout buffers to 64k physical pages when needed. To: Matthew Brost Cc: intel-xe@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, =?UTF-8?Q?Zbigniew_Kempczy=C5=84ski?= , Matthew Auld , Rodrigo Vivi , =?UTF-8?Q?Thomas_Hellstr=C3=B6m?= , =?UTF-8?Q?Juha-Pekka_Heikkil=C3=A4?= References: <20240826170117.327709-1-maarten.lankhorst@linux.intel.com> <20240826170117.327709-3-maarten.lankhorst@linux.intel.com> <361abc93-0246-4f21-b235-4e0699682ef3@linux.intel.com> Content-Language: en-US From: Maarten Lankhorst In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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" Hey, Den 2024-08-27 kl. 05:11, skrev Matthew Brost: > On Mon, Aug 26, 2024 at 09:42:54PM +0200, Maarten Lankhorst wrote: >> Hey, >> >> Den 2024-08-26 kl. 21:30, skrev Matthew Brost: >>> On Mon, Aug 26, 2024 at 07:01:16PM +0200, Maarten Lankhorst wrote: >>>> For CCS formats on affected platforms, CCS can be used freely, but >>>> display engine requires a multiple of 64k physical pages. No other >>>> changes are needed. >>>> >>>> At the BO creation time we don't know if the BO will be used for CCS >>>> or not. If the scanout flag is set, and the BO is a multiple of 64k, >>>> we take the safe route and force the physical alignment of 64k pages. >>>> >>>> If the BO is not a multiple of 64k, or the scanout flag was not set >>>> at BO creation, we reject it for usage as CCS in display. The physical >>>> pages are likely not aligned correctly, and this will cause corruption >>>> when used as FB. >>>> >>>> The scanout flag and size being a multiple of 64k are used together >>>> to enforce 64k physical placement. >>>> >>>> VM_BIND is completely unaffected, mappings to a VM can still be aligned >>>> to 4k, just like for normal buffers. >>>> >>>> Signed-off-by: Zbigniew Kempczyński >>>> Signed-off-by: Maarten Lankhorst >>>> Cc: Matthew Auld >>>> Cc: Rodrigo Vivi >>>> Cc: Thomas Hellström >>>> Cc: Maarten Lankhorst >>>> Cc: Juha-Pekka Heikkilä >>>> --- >>>> drivers/gpu/drm/xe/display/intel_fb_bo.c | 9 +++++++++ >>>> drivers/gpu/drm/xe/xe_bo.c | 7 +++++++ >>>> drivers/gpu/drm/xe/xe_vm.c | 11 ++++++++++- >>>> 3 files changed, 26 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/drivers/gpu/drm/xe/display/intel_fb_bo.c b/drivers/gpu/drm/xe/display/intel_fb_bo.c >>>> index f835492f73fb4..63ce97cc4cfef 100644 >>>> --- a/drivers/gpu/drm/xe/display/intel_fb_bo.c >>>> +++ b/drivers/gpu/drm/xe/display/intel_fb_bo.c >>>> @@ -7,6 +7,7 @@ >>>> #include >>>> >>>> #include "intel_display_types.h" >>>> +#include "intel_fb.h" >>>> #include "intel_fb_bo.h" >>>> #include "xe_bo.h" >>>> >>>> @@ -28,6 +29,14 @@ int intel_fb_bo_framebuffer_init(struct intel_framebuffer *intel_fb, >>>> struct xe_device *xe = to_xe_device(bo->ttm.base.dev); >>>> int ret; >>>> >>>> + /* >>>> + * Some modifiers require physical alignment of 64KiB VRAM pages; >>>> + * require that the BO in those cases is created correctly. >>>> + */ >>>> + if (XE_IOCTL_DBG(xe, intel_fb_needs_64k_phys(mode_cmd->modifier[0]) && >>>> + !(bo->flags & XE_BO_FLAG_NEEDS_64K))) >>>> + return -EINVAL; >>> >>> I don't think this is correct use of this macro as XE_BO_FLAG_NEEDS_64K >>> is an internal flag we set and typically this macro is used to santize >>> user input. An assert here or WARN would make more sense. >> Ideally we'd use 'is bo created as scanout', but that flag can be set by fb_init too, so if the BO was used for normal 4-tiled before, then as CCS it would pass when it wouldn't be valid. >> >> I could change it to bo_created_with_scanout_flag_on_64k_platform inline, but I doubt that's more readable. :) >> > > Not trying to block the patch and really don't know anything about > display but still think XE_IOCTL_DBG should replaced by either an > assert or WARN (or Xe flavor of warn). Kinda pedantic but we really are > trying hard to uniformly use these types of macros and this just doesn't > look correct. mode_cmd->modifier[0] is passed from userspace without validation, and this function is called very early on in fb creation. Anything more than XE_IOCTL_DBG would be invalid here.