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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 D0F58C433ED for ; Tue, 18 May 2021 11:17:20 +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 8894C61001 for ; Tue, 18 May 2021 11:17:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8894C61001 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=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1DBFF6EB28; Tue, 18 May 2021 11:17:18 +0000 (UTC) Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id F17A46EB27; Tue, 18 May 2021 11:17:16 +0000 (UTC) IronPort-SDR: yI+gj/YwlRdn4l1XOAm18pfWTlUVeftaGMdKr6oICcwIjHriwqMvcEAM/JBlNBN+4kGNZdU69T 5Tt9mZ53MsoA== X-IronPort-AV: E=McAfee;i="6200,9189,9987"; a="198733675" X-IronPort-AV: E=Sophos;i="5.82,310,1613462400"; d="scan'208";a="198733675" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 May 2021 04:17:16 -0700 IronPort-SDR: RP9CB410mQszfPj4yd/i86Q5F8YvKUlcCUp6PK4SNYelpI+h+6rEqT4Acl5z0nIaA7R02Q0Xqh 7nYDUxPmc/rA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,310,1613462400"; d="scan'208";a="472903493" Received: from stinkbox.fi.intel.com (HELO stinkbox) ([10.237.72.171]) by orsmga001.jf.intel.com with SMTP; 18 May 2021 04:17:12 -0700 Received: by stinkbox (sSMTP sendmail emulation); Tue, 18 May 2021 14:17:11 +0300 Date: Tue, 18 May 2021 14:17:11 +0300 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Emil Velikov Subject: Re: [PATCH] drm/i915: only disable default vga device Message-ID: References: <20210516171432.1734268-1-emil.l.velikov@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Patchwork-Hint: comment 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: Intel Graphics Development , ML dri-devel , Rodrigo Vivi , kernel@collabora.com Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Tue, May 18, 2021 at 12:09:56PM +0100, Emil Velikov wrote: > Hi Ville, > > On Mon, 17 May 2021 at 18:24, Ville Syrjälä > wrote: > > > > On Sun, May 16, 2021 at 06:14:32PM +0100, Emil Velikov wrote: > > > From: Vivek Das Mohapatra > > > > > > This patch is to do with seamless handover, eg when the sequence is > > > bootloader → plymouth → desktop. > > > > > > It switches the vga arbiter from the "other" GPU to the default one > > > (intel in this case), so the driver can issue some io(). > > > > I don't understand what this commit message is trying to say. > > > Bunch of context is lost due to the patch age, so I'm not 100% sure of > the actual hardware setup where this occurs. > Does the following make sense? > > Currently on dual GPU systems, we do not get seamless handover as the > output flickers during the transition bootloader -> plymouth -> > desktop. > This happens as a result of switching (via the VGA arbiter) from the > "other" GPU back to the default i915 one and issuing io() commands. Hmm. Does this work? --- a/drivers/gpu/drm/i915/display/intel_vga.c +++ b/drivers/gpu/drm/i915/display/intel_vga.c @@ -29,6 +29,9 @@ void intel_vga_disable(struct drm_i915_private *dev_priv) i915_reg_t vga_reg = intel_vga_cntrl_reg(dev_priv); u8 sr1; + if (intel_de_read(dev_priv, vga_reg) & VGA_DISP_DISABLE) + return; + /* WaEnableVGAAccessThroughIOPort:ctg,elk,ilk,snb,ivb,vlv,hsw */ vga_get_uninterruptible(pdev, VGA_RSRC_LEGACY_IO); outb(SR01, VGA_SR_INDEX); -- Ville Syrjälä Intel 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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 E986DC433B4 for ; Tue, 18 May 2021 11:17:18 +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 A871B610FA for ; Tue, 18 May 2021 11:17:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A871B610FA 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 10C636EB27; Tue, 18 May 2021 11:17:18 +0000 (UTC) Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id F17A46EB27; Tue, 18 May 2021 11:17:16 +0000 (UTC) IronPort-SDR: yI+gj/YwlRdn4l1XOAm18pfWTlUVeftaGMdKr6oICcwIjHriwqMvcEAM/JBlNBN+4kGNZdU69T 5Tt9mZ53MsoA== X-IronPort-AV: E=McAfee;i="6200,9189,9987"; a="198733675" X-IronPort-AV: E=Sophos;i="5.82,310,1613462400"; d="scan'208";a="198733675" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 May 2021 04:17:16 -0700 IronPort-SDR: RP9CB410mQszfPj4yd/i86Q5F8YvKUlcCUp6PK4SNYelpI+h+6rEqT4Acl5z0nIaA7R02Q0Xqh 7nYDUxPmc/rA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,310,1613462400"; d="scan'208";a="472903493" Received: from stinkbox.fi.intel.com (HELO stinkbox) ([10.237.72.171]) by orsmga001.jf.intel.com with SMTP; 18 May 2021 04:17:12 -0700 Received: by stinkbox (sSMTP sendmail emulation); Tue, 18 May 2021 14:17:11 +0300 Date: Tue, 18 May 2021 14:17:11 +0300 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Emil Velikov Message-ID: References: <20210516171432.1734268-1-emil.l.velikov@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-Patchwork-Hint: comment Subject: Re: [Intel-gfx] [PATCH] drm/i915: only disable default vga device 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 Graphics Development , ML dri-devel , kernel@collabora.com Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" T24gVHVlLCBNYXkgMTgsIDIwMjEgYXQgMTI6MDk6NTZQTSArMDEwMCwgRW1pbCBWZWxpa292IHdy b3RlOgo+IEhpIFZpbGxlLAo+IAo+IE9uIE1vbiwgMTcgTWF5IDIwMjEgYXQgMTg6MjQsIFZpbGxl IFN5cmrDpGzDpAo+IDx2aWxsZS5zeXJqYWxhQGxpbnV4LmludGVsLmNvbT4gd3JvdGU6Cj4gPgo+ ID4gT24gU3VuLCBNYXkgMTYsIDIwMjEgYXQgMDY6MTQ6MzJQTSArMDEwMCwgRW1pbCBWZWxpa292 IHdyb3RlOgo+ID4gPiBGcm9tOiBWaXZlayBEYXMgTW9oYXBhdHJhIDx2aXZla0Bjb2xsYWJvcmEu Y29tPgo+ID4gPgo+ID4gPiBUaGlzIHBhdGNoIGlzIHRvIGRvIHdpdGggc2VhbWxlc3MgaGFuZG92 ZXIsIGVnIHdoZW4gdGhlIHNlcXVlbmNlIGlzCj4gPiA+IGJvb3Rsb2FkZXIg4oaSIHBseW1vdXRo IOKGkiBkZXNrdG9wLgo+ID4gPgo+ID4gPiBJdCBzd2l0Y2hlcyB0aGUgdmdhIGFyYml0ZXIgZnJv bSB0aGUgIm90aGVyIiBHUFUgdG8gdGhlIGRlZmF1bHQgb25lCj4gPiA+IChpbnRlbCBpbiB0aGlz IGNhc2UpLCBzbyB0aGUgZHJpdmVyIGNhbiBpc3N1ZSBzb21lIGlvKCkuCj4gPgo+ID4gSSBkb24n dCB1bmRlcnN0YW5kIHdoYXQgdGhpcyBjb21taXQgbWVzc2FnZSBpcyB0cnlpbmcgdG8gc2F5Lgo+ ID4KPiBCdW5jaCBvZiBjb250ZXh0IGlzIGxvc3QgZHVlIHRvIHRoZSBwYXRjaCBhZ2UsIHNvIEkn bSBub3QgMTAwJSBzdXJlIG9mCj4gdGhlIGFjdHVhbCBoYXJkd2FyZSBzZXR1cCB3aGVyZSB0aGlz IG9jY3Vycy4KPiBEb2VzIHRoZSBmb2xsb3dpbmcgbWFrZSBzZW5zZT8KPiAKPiBDdXJyZW50bHkg b24gZHVhbCBHUFUgc3lzdGVtcywgd2UgZG8gbm90IGdldCBzZWFtbGVzcyBoYW5kb3ZlciBhcyB0 aGUKPiBvdXRwdXQgZmxpY2tlcnMgZHVyaW5nIHRoZSB0cmFuc2l0aW9uIGJvb3Rsb2FkZXIgLT4g cGx5bW91dGggLT4KPiBkZXNrdG9wLgo+IFRoaXMgaGFwcGVucyBhcyBhIHJlc3VsdCBvZiBzd2l0 Y2hpbmcgKHZpYSB0aGUgVkdBIGFyYml0ZXIpIGZyb20gdGhlCj4gIm90aGVyIiBHUFUgYmFjayB0 byB0aGUgZGVmYXVsdCBpOTE1IG9uZSBhbmQgaXNzdWluZyBpbygpIGNvbW1hbmRzLgoKSG1tLiBE b2VzIHRoaXMgd29yaz8KCi0tLSBhL2RyaXZlcnMvZ3B1L2RybS9pOTE1L2Rpc3BsYXkvaW50ZWxf dmdhLmMKKysrIGIvZHJpdmVycy9ncHUvZHJtL2k5MTUvZGlzcGxheS9pbnRlbF92Z2EuYwpAQCAt MjksNiArMjksOSBAQCB2b2lkIGludGVsX3ZnYV9kaXNhYmxlKHN0cnVjdCBkcm1faTkxNV9wcml2 YXRlICpkZXZfcHJpdikKICAgICAgICBpOTE1X3JlZ190IHZnYV9yZWcgPSBpbnRlbF92Z2FfY250 cmxfcmVnKGRldl9wcml2KTsKICAgICAgICB1OCBzcjE7CiAKKyAgICAgICBpZiAoaW50ZWxfZGVf cmVhZChkZXZfcHJpdiwgdmdhX3JlZykgJiBWR0FfRElTUF9ESVNBQkxFKQorICAgICAgICAgICAg ICAgcmV0dXJuOworCiAgICAgICAgLyogV2FFbmFibGVWR0FBY2Nlc3NUaHJvdWdoSU9Qb3J0OmN0 ZyxlbGssaWxrLHNuYixpdmIsdmx2LGhzdyAqLwogICAgICAgIHZnYV9nZXRfdW5pbnRlcnJ1cHRp YmxlKHBkZXYsIFZHQV9SU1JDX0xFR0FDWV9JTyk7CiAgICAgICAgb3V0YihTUjAxLCBWR0FfU1Jf SU5ERVgpOwoKLS0gClZpbGxlIFN5cmrDpGzDpApJbnRlbApfX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fXwpJbnRlbC1nZnggbWFpbGluZyBsaXN0CkludGVsLWdm eEBsaXN0cy5mcmVlZGVza3RvcC5vcmcKaHR0cHM6Ly9saXN0cy5mcmVlZGVza3RvcC5vcmcvbWFp bG1hbi9saXN0aW5mby9pbnRlbC1nZngK