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 X-Spam-Level: X-Spam-Status: No, score=-13.8 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 autolearn=ham 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 73EABC433E0 for ; Mon, 18 Jan 2021 09:57:08 +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 F21D922240 for ; Mon, 18 Jan 2021 09:57:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F21D922240 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 944366E177; Mon, 18 Jan 2021 09:57:07 +0000 (UTC) Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by gabe.freedesktop.org (Postfix) with ESMTPS id CA04A6E177 for ; Mon, 18 Jan 2021 09:57:06 +0000 (UTC) IronPort-SDR: 3IM1IovxgnoEFnT010Z/imIc+F6xFXG+lwpcjZqMwHvqpUFitzsivWr0FvogKoIjaIj54uJz3g 4BtMELSbe47A== X-IronPort-AV: E=McAfee;i="6000,8403,9867"; a="178868377" X-IronPort-AV: E=Sophos;i="5.79,356,1602572400"; d="scan'208";a="178868377" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jan 2021 01:56:59 -0800 IronPort-SDR: cinEa2j5fV6NUNofRlK0hqmdRC41DauSZiHRLpHJTxF3pbZnsCd8+Gfj6n/V8M9vwanoR6lOdH e8PCo6Zdfjzg== X-IronPort-AV: E=Sophos;i="5.79,356,1602572400"; d="scan'208";a="383511504" Received: from moshear-mobl.ger.corp.intel.com (HELO localhost) ([10.251.186.10]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jan 2021 01:56:57 -0800 From: Jani Nikula To: Zhenyu Wang , Joonas Lahtinen In-Reply-To: <20210118060406.GA15982@zhen-hp.sh.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <87im8soq2w.fsf@intel.com> <20210114005819.4290-1-xiong.y.zhang@intel.com> <20210114051410.GU15982@zhen-hp.sh.intel.com> <878s8upj75.fsf@intel.com> <161070850877.79726.12218329205250979912@jlahtine-mobl.ger.corp.intel.com> <20210118060406.GA15982@zhen-hp.sh.intel.com> Date: Mon, 18 Jan 2021 11:56:53 +0200 Message-ID: <87im7uo9ei.fsf@intel.com> MIME-Version: 1.0 Subject: Re: [Intel-gfx] [PATCH v4] drm/i915: Try to guess PCH type even without ISA bridge 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: , Cc: intel-gfx@lists.freedesktop.org, chris@chris-wilson.co.uk Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Mon, 18 Jan 2021, Zhenyu Wang wrote: > On 2021.01.15 13:01:49 +0200, Joonas Lahtinen wrote: >> Quoting Jani Nikula (2021-01-15 12:50:54) >> > On Thu, 14 Jan 2021, Zhenyu Wang wrote: >> > > On 2021.01.14 08:58:19 +0800, Xiong Zhang wrote: >> > >> From: Zhenyu Wang >> > >> >> > >> Some vmm like hyperv and crosvm don't supply any ISA bridge to their guest, >> > >> when igd passthrough is equipped on these vmm, guest i915 display may >> > >> couldn't work as guest i915 detects PCH_NONE pch type. >> > >> >> > >> When i915 runs as guest, this patch guess pch type through gpu type even >> > >> without ISA bridge. >> > >> >> > >> v2: Fix CI warning >> > >> v3: Add HAS_DISPLAY()= true condition beforce guessing virt pch, then >> > >> refactori. >> > >> v4: Fix CI warning >> > >> >> > >> Signed-off-by: Zhenyu Wang >> > >> Signed-off-by: Xiong Zhang >> > >> --- >> > >> drivers/gpu/drm/i915/i915_drv.h | 7 +++++- >> > >> drivers/gpu/drm/i915/intel_pch.c | 39 ++++++++++++++++++-------------- >> > >> 2 files changed, 28 insertions(+), 18 deletions(-) >> > >> >> > > >> > > Good to me, thanks! I think this should change author to you. :) >> > > >> > > Reviewed-by: Zhenyu Wang >> > >> > Pushed to drm-intel-next, thanks for the patch and review. I ended up >> > retaining Zhenyu's authorship, and added >> > >> > Co-developed-by: Xiong Zhang >> >> This only works for the majority of SKUs which happen to use the PCH >> that is most common. I NAKed very similar patch some years back asking >> for a reliable means to detect the PCH type instead. >> >> Has there been any attempt to introduce such mechanism? >> > > I think the situation is that if just passing through GPU device, as > full device model depends on userspace VMM, we have no way to properly > detect PCH type from device, e.g in case of one GEN device which could > live with two or more different PCH types. It's better if either we > have properly defined way to detect through GPU device or display arch > always defines CPU/PCH display in pair. > > Currently this tries to assume PCH with best effort that fixed bunch of > problems. On really mismatch case, how about adding i915 parameter to > override PCH type? As that won't add dependency on other components.. In general, module parameters should not be considered a fix or a solution. BR, Jani. -- Jani Nikula, Intel Open Source Graphics Center _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx