linux-kernel - [PATCH 04/12] drm/amdgpu: Use devm aperture helpers for sysfb restore on probe failure

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Message-ID: <20251229215906.3688205-5-zack.rusin@broadcom.com>
Date: Mon, 29 Dec 2025 16:58:10 -0500
From: Zack Rusin <zack.rusin@...adcom.com>
To: dri-devel@...ts.freedesktop.org
Cc: Alex Deucher <alexander.deucher@....com>,
	Christian König <christian.koenig@....com>,
	David Airlie <airlied@...il.com>,
	Simona Vetter <simona@...ll.ch>,
	Lijo Lazar <lijo.lazar@....com>,
	Hawking Zhang <Hawking.Zhang@....com>,
	Mario Limonciello <mario.limonciello@....com>,
	Ce Sun <cesun102@....com>,
	"Mario Limonciello (AMD)" <superm1@...nel.org>,
	Timur Kristóf <timur.kristof@...il.com>,
	Vitaly Prosyak <vitaly.prosyak@....com>,
	amd-gfx@...ts.freedesktop.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH 04/12] drm/amdgpu: Use devm aperture helpers for sysfb restore on probe failure

Use devm_aperture_remove_conflicting_pci_devices() instead of the
non-devm variant to automatically restore the system framebuffer
(efifb/simpledrm) if the driver's probe fails after removing the
firmware framebuffer.

Call devm_aperture_remove_conflicting_pci_devices_done() after
successful probe to cancel the automatic restore, as the driver
is now responsible for display output.

The aperture removal only applies to VGA and display class devices,
matching the existing behavior. This ensures users don't lose
display output if the amdgpu driver fails to probe after removing
the firmware framebuffer.

Signed-off-by: Zack Rusin <zack.rusin@...adcom.com>
Cc: Alex Deucher <alexander.deucher@....com>
Cc: "Christian König" <christian.koenig@....com>
Cc: David Airlie <airlied@...il.com>
Cc: Simona Vetter <simona@...ll.ch>
Cc: Lijo Lazar <lijo.lazar@....com>
Cc: Hawking Zhang <Hawking.Zhang@....com>
Cc: Mario Limonciello <mario.limonciello@....com>
Cc: Ce Sun <cesun102@....com>
Cc: "Mario Limonciello (AMD)" <superm1@...nel.org>
Cc: "Timur Kristóf" <timur.kristof@...il.com>
Cc: Vitaly Prosyak <vitaly.prosyak@....com>
Cc: amd-gfx@...ts.freedesktop.org
Cc: dri-devel@...ts.freedesktop.org
Cc: linux-kernel@...r.kernel.org
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 9 +++++++--
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c    | 7 +++++++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 58c3ffe707d1..6c867657225e 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -4737,8 +4737,13 @@ int amdgpu_device_init(struct amdgpu_device *adev,
 	 */
 	if ((pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA ||
 	    (pdev->class >> 8) == PCI_CLASS_DISPLAY_OTHER) {
-		/* Get rid of things like offb */
-		r = aperture_remove_conflicting_pci_devices(adev->pdev, amdgpu_kms_driver.name);
+		/*
+		 * Get rid of things like offb. Use devm variant to
+		 * automatically restore sysfb if probe fails. This ensures
+		 * the user doesn't lose display if our probe fails after
+		 * removing the firmware framebuffer (efifb/simpledrm).
+		 */
+		r = devm_aperture_remove_conflicting_pci_devices(adev->pdev, amdgpu_kms_driver.name);
 		if (r)
 			return r;
 	}
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index 2dfbddcef9ab..fc2d2dbaebe8 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -32,6 +32,7 @@
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_vblank.h>
 
+#include <linux/aperture.h>
 #include <linux/cc_platform.h>
 #include <linux/dynamic_debug.h>
 #include <linux/module.h>
@@ -2528,6 +2529,12 @@ static int amdgpu_pci_probe(struct pci_dev *pdev,
 			amdgpu_get_secondary_funcs(adev);
 	}
 
+	/*
+	 * Probe succeeded - cancel the automatic sysfb restore action.
+	 * We're now responsible for display output.
+	 */
+	devm_aperture_remove_conflicting_pci_devices_done(pdev);
+
 	return 0;
 
 err_pci:
-- 
2.48.1