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Message-ID: <74994ce2-c060-f662-9210-14d09a15162f@linux.dev>
Date:   Thu, 20 Jul 2023 06:44:29 +0800
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Subject: Re: [PATCH v3 4/9] PCI/VGA: Improve the default VGA device selection
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To:     suijingfeng <suijingfeng@loongson.cn>,
        Bjorn Helgaas <helgaas@kernel.org>
Cc:     David Airlie <airlied@gmail.com>, amd-gfx@lists.freedesktop.org,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
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        Alex Deucher <alexander.deucher@amd.com>,
        Christian Konig <christian.koenig@amd.com>,
        Pan Xinhui <Xinhui.Pan@amd.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Jani Nikula <jani.nikula@linux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@intel.com>,
        Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>,
        Ben Skeggs <bskeggs@redhat.com>,
        Karol Herbst <kherbst@redhat.com>,
        Lyude Paul <lyude@redhat.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Alex Williamson <alex.williamson@redhat.com>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Hawking Zhang <Hawking.Zhang@amd.com>,
        Mario Limonciello <mario.limonciello@amd.com>,
        Lijo Lazar <lijo.lazar@amd.com>,
        YiPeng Chai <YiPeng.Chai@amd.com>,
        Bokun Zhang <Bokun.Zhang@amd.com>,
        Likun Gao <Likun.Gao@amd.com>,
        Ville Syrjala <ville.syrjala@linux.intel.com>,
        Jason Gunthorpe <jgg@ziepe.ca>,
        Kevin Tian <kevin.tian@intel.com>,
        Cornelia Huck <cohuck@redhat.com>,
        Yishai Hadas <yishaih@nvidia.com>,
        Abhishek Sahu <abhsahu@nvidia.com>,
        Yi Liu <yi.l.liu@intel.com>,
        Jani Nikula <jani.nikula@intel.com>
References: <20230719193233.GA511659@bhelgaas>
 <f87a48c6-909e-39ba-62b0-289e78798540@loongson.cn>
From:   Sui Jingfeng <sui.jingfeng@linux.dev>
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On 2023/7/20 06:32, suijingfeng wrote:
> it will be works no matter CONFIG_DRM_AST=m or CONFIG_DRM_AST=y


It will be works regardless of CONFIG_DRM_AST=m or CONFIG_DRM_AST=y.

When vgaarb call to the device driver, device driver already loaded 
successfully.

and the PCI(e) device emulation already finished.


So the last change the vgaarb gave us to override is actually happen 
very late.

But it will be happen as long as the device driver get loaded successfully.