linux-kernel - [PATCH v5 8/9] fbcon: Use screen info to find primary device

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Message-ID: <20250624203042.1102346-9-superm1@kernel.org>
Date: Tue, 24 Jun 2025 15:30:41 -0500
From: Mario Limonciello <superm1@...nel.org>
To: Bjorn Helgaas <bhelgaas@...gle.com>
Cc: Alex Deucher <alexander.deucher@....com>,
	Christian König <christian.koenig@....com>,
	David Airlie <airlied@...il.com>,
	Simona Vetter <simona@...ll.ch>,
	Lukas Wunner <lukas@...ner.de>,
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
	Maxime Ripard <mripard@...nel.org>,
	Thomas Zimmermann <tzimmermann@...e.de>,
	David Woodhouse <dwmw2@...radead.org>,
	Lu Baolu <baolu.lu@...ux.intel.com>,
	Joerg Roedel <joro@...tes.org>,
	Will Deacon <will@...nel.org>,
	Robin Murphy <robin.murphy@....com>,
	Alex Williamson <alex.williamson@...hat.com>,
	Jaroslav Kysela <perex@...ex.cz>,
	Takashi Iwai <tiwai@...e.com>,
	dri-devel@...ts.freedesktop.org (open list:DRM DRIVERS),
	linux-kernel@...r.kernel.org (open list),
	iommu@...ts.linux.dev (open list:INTEL IOMMU (VT-d)),
	linux-pci@...r.kernel.org (open list:PCI SUBSYSTEM),
	kvm@...r.kernel.org (open list:VFIO DRIVER),
	linux-sound@...r.kernel.org (open list:SOUND),
	Daniel Dadap <ddadap@...dia.com>,
	Mario Limonciello <mario.limonciello@....com>
Subject: [PATCH v5 8/9] fbcon: Use screen info to find primary device

From: Mario Limonciello <mario.limonciello@....com>

On systems with non VGA GPUs fbcon can't find the primary GPU because
video_is_primary_device() only checks the VGA arbiter.

Add a screen info check to video_is_primary_device() so that callers
can get accurate data on such systems.

Suggested-by: Thomas Zimmermann <tzimmermann@...e.de>
Signed-off-by: Mario Limonciello <mario.limonciello@....com>
---
v5:
 * Only change video-common.c
v4:
 * use helper
---
 arch/x86/video/video-common.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/arch/x86/video/video-common.c b/arch/x86/video/video-common.c
index 81fc97a2a837a..917568e4d7fb1 100644
--- a/arch/x86/video/video-common.c
+++ b/arch/x86/video/video-common.c
@@ -9,6 +9,7 @@
 
 #include <linux/module.h>
 #include <linux/pci.h>
+#include <linux/screen_info.h>
 #include <linux/vgaarb.h>
 
 #include <asm/video.h>
@@ -27,6 +28,7 @@ EXPORT_SYMBOL(pgprot_framebuffer);
 
 bool video_is_primary_device(struct device *dev)
 {
+	struct screen_info *si = &screen_info;
 	struct pci_dev *pdev;
 
 	if (!dev_is_pci(dev))
@@ -34,7 +36,16 @@ bool video_is_primary_device(struct device *dev)
 
 	pdev = to_pci_dev(dev);
 
-	return (pdev == vga_default_device());
+	if (!pci_is_display(pdev))
+		return false;
+
+	if (pdev == vga_default_device())
+		return true;
+
+	if (pdev == screen_info_pci_dev(si))
+		return true;
+
+	return false;
 }
 EXPORT_SYMBOL(video_is_primary_device);
 
-- 
2.43.0