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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 62F39C433F5 for ; Thu, 6 Jan 2022 06:44:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234937AbiAFGoo (ORCPT ); Thu, 6 Jan 2022 01:44:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37422 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234656AbiAFGon (ORCPT ); Thu, 6 Jan 2022 01:44:43 -0500 Received: from mail-ua1-x929.google.com (mail-ua1-x929.google.com [IPv6:2607:f8b0:4864:20::929]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B3AC7C061245; Wed, 5 Jan 2022 22:44:43 -0800 (PST) Received: by mail-ua1-x929.google.com with SMTP id o20so2675697uat.2; Wed, 05 Jan 2022 22:44:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=yAk2Gs4W1UK9ZJv061rWxHpztwooZWsfp8OzDdXBAw0=; b=HuttzNqQ3QYmrhIpgOkK5VK32WBu1x9CqUT3eHe1nC+i6T2Ew81/ahBnhfAgeAj5Sh oF70HZM5yU9QzYOEQAutZY0rmMujxD20Ox32osUtrzyEZusahEXfRZvIMPUaNmjXAT0j GE9H8EjHSQCKsNCsUOAY4Y62REAu73Pc2fdx2/JfAoDpd4dJtqc7jybR7F/bINLJymr/ uuw7CeijZkoO6uGbbY8p22P2S3B+oOZ+sMrExFPGVvGs7dSmZiNDPoy75QHvvvsgfJaY iuWvU35bNQV5NZvKwt4bi+lC/YmiUsug8oX/t/acS+Vd7Elp4eOVPChbMDsIFVobxJSU KC7g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=yAk2Gs4W1UK9ZJv061rWxHpztwooZWsfp8OzDdXBAw0=; b=hVQyv69R4rvfmq5EvOSDdZq0OpDElN6EEx3UkyN8rAv9CohsRfEy0E8w/6yLkv3MXk a4jsyo0nQKOu9KJOPr/NsJZyUFb7KbOlGogVcnZS5g0r45H+dW51zmPw8nWc0JfrW8vC whFSzJOuawN9lhY/iZKCxQDqtR7T6guiSIAT9ifYtb5Jf2PXEJwhTccqAbjqaIaYEVAw Y0bdBYCDVq/Ave+yZWGa9e1lvo+hGQdxa2WRoqiWqI/hmx/y0zzp24th7pimjl1fon1A uNOayg1b9Ok0XJxB4uXe/9Tke3VO/xEDJdmtX+edOt/rg/tNbRrSbn4hVSe3U5/jCR8S CUAw== X-Gm-Message-State: AOAM5324Wx0T5Cl0FXTB3HnjLhymW3RPxW6JsN/aIIv56IK7mxI8VJU+ 8Okp8oOaNTcKufJAKqeKCsAaz5OSeaPnjlVdulQ= X-Google-Smtp-Source: ABdhPJz10DHXq5phLZL76z2EfPvDtVca/IjryhPZWjoVVqO9xbEPcYGvb+f6XHcMlDHjAyjLkzDvMGcIp1DtuaCi8nQ= X-Received: by 2002:a67:b807:: with SMTP id i7mr16383794vsf.52.1641451482782; Wed, 05 Jan 2022 22:44:42 -0800 (PST) MIME-Version: 1.0 References: <20220106000658.243509-1-helgaas@kernel.org> <20220106000658.243509-5-helgaas@kernel.org> In-Reply-To: <20220106000658.243509-5-helgaas@kernel.org> From: Huacai Chen Date: Thu, 6 Jan 2022 14:44:42 +0800 Message-ID: Subject: Re: [PATCH v8 04/10] vgaarb: Move framebuffer detection to ADD_DEVICE path To: Bjorn Helgaas Cc: David Airlie , Daniel Vetter , Xuefeng Li , Huacai Chen , linux-pci , Maling list - DRI developers , LKML , Bjorn Helgaas , =?UTF-8?Q?Bruno_Pr=C3=A9mont?= Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Bjorn, On Thu, Jan 6, 2022 at 8:07 AM Bjorn Helgaas wrote: > > From: Bjorn Helgaas > > Previously we selected a device that owns the boot framebuffer as the > default device in vga_arb_select_default_device(). This was only done in > the vga_arb_device_init() subsys_initcall, so devices enumerated later, > e.g., by pcibios_init(), were not eligible. > > Fix this by moving the framebuffer device selection from > vga_arb_select_default_device() to vga_arbiter_add_pci_device(), which is > called after every PCI device is enumerated, either by the > vga_arb_device_init() subsys_initcall or as an ADD_DEVICE notifier. > > Note that if vga_arb_select_default_device() found a device owning the bo= ot > framebuffer, it unconditionally set it to be the default VGA device, and = no > subsequent device could replace it. > > Link: https://lore.kernel.org/r/20211015061512.2941859-7-chenhuacai@loong= son.cn > Based-on-patch-by: Huacai Chen > Signed-off-by: Bjorn Helgaas > Cc: Bruno Pr=C3=A9mont > --- > drivers/gpu/vga/vgaarb.c | 37 +++++++++++++++++-------------------- > 1 file changed, 17 insertions(+), 20 deletions(-) > > diff --git a/drivers/gpu/vga/vgaarb.c b/drivers/gpu/vga/vgaarb.c > index b0ae0f177c6f..aefa4f406f7d 100644 > --- a/drivers/gpu/vga/vgaarb.c > +++ b/drivers/gpu/vga/vgaarb.c > @@ -72,6 +72,7 @@ struct vga_device { > unsigned int io_norm_cnt; /* normal IO count */ > unsigned int mem_norm_cnt; /* normal MEM count */ > bool bridge_has_one_vga; > + bool is_framebuffer; /* BAR covers firmware framebuffer */ > unsigned int (*set_decode)(struct pci_dev *pdev, bool decode); > }; > > @@ -565,10 +566,9 @@ void vga_put(struct pci_dev *pdev, unsigned int rsrc= ) > } > EXPORT_SYMBOL(vga_put); > > -static void __init vga_select_framebuffer_device(struct pci_dev *pdev) > +static bool vga_is_framebuffer_device(struct pci_dev *pdev) > { > #if defined(CONFIG_X86) || defined(CONFIG_IA64) > - struct device *dev =3D &pdev->dev; > u64 base =3D screen_info.lfb_base; > u64 size =3D screen_info.lfb_size; > u64 limit; > @@ -583,15 +583,6 @@ static void __init vga_select_framebuffer_device(str= uct pci_dev *pdev) > > limit =3D base + size; > > - /* > - * Override vga_arbiter_add_pci_device()'s I/O based detection > - * as it may take the wrong device (e.g. on Apple system under > - * EFI). > - * > - * Select the device owning the boot framebuffer if there is > - * one. > - */ > - > /* Does firmware framebuffer belong to us? */ > for (i =3D 0; i < DEVICE_COUNT_RESOURCE; i++) { > flags =3D pci_resource_flags(pdev, i); > @@ -608,13 +599,10 @@ static void __init vga_select_framebuffer_device(st= ruct pci_dev *pdev) > if (base < start || limit >=3D end) > continue; > > - if (!vga_default_device()) > - vgaarb_info(dev, "setting as boot device\n"); > - else if (pdev !=3D vga_default_device()) > - vgaarb_info(dev, "overriding boot device\n"); > - vga_set_default_device(pdev); > + return true; > } > #endif > + return false; > } > > static bool vga_arb_integrated_gpu(struct device *dev) > @@ -635,6 +623,7 @@ static bool vga_arb_integrated_gpu(struct device *dev= ) > static bool vga_is_boot_device(struct vga_device *vgadev) > { > struct vga_device *boot_vga =3D vgadev_find(vga_default_device())= ; > + struct pci_dev *pdev =3D vgadev->pdev; > > /* > * We select the default VGA device in this order: > @@ -645,6 +634,18 @@ static bool vga_is_boot_device(struct vga_device *vg= adev) > * Other device (see vga_arb_select_default_device()) > */ > > + /* > + * We always prefer a firmware framebuffer, so if we've already > + * found one, there's no need to consider vgadev. > + */ > + if (boot_vga && boot_vga->is_framebuffer) > + return false; > + > + if (vga_is_framebuffer_device(pdev)) { > + vgadev->is_framebuffer =3D true; > + return true; > + } Maybe it is better to rename vga_is_framebuffer_device() to vga_is_firmware_device() and rename is_framebuffer to is_fw_framebuffer? Huacai > + > /* > * A legacy VGA device has MEM and IO enabled and any bridges > * leading to it have PCI_BRIDGE_CTL_VGA enabled so the legacy > @@ -1531,10 +1532,6 @@ static void __init vga_arb_select_default_device(v= oid) > struct pci_dev *pdev, *found =3D NULL; > struct vga_device *vgadev; > > - list_for_each_entry(vgadev, &vga_list, list) { > - vga_select_framebuffer_device(vgadev->pdev); > - } > - > if (!vga_default_device()) { > list_for_each_entry_reverse(vgadev, &vga_list, list) { > struct device *dev =3D &vgadev->pdev->dev; > -- > 2.25.1 >