Hi
Am 06.05.25 um 00:05 schrieb Sasha Levin:
From: Alex Deucher alexander.deucher@amd.com
[ Upstream commit e00e5c223878a60e391e5422d173c3382d378f87 ]
Move to probe so we can check the PCI device type and only apply the drm_firmware_drivers_only() check for PCI DISPLAY classes. Also add a module parameter to override the nomodeset kernel parameter as a workaround for platforms that have this hardcoded on their kernel command lines.
I just came across this patch because it got backported into various older releases. It was part of the series at [1]. From the cover letter:
There are a number of systems and cloud providers out there that have nomodeset hardcoded in their kernel parameters to block nouveau for the nvidia driver. This prevents the amdgpu driver from loading. Unfortunately the end user cannot easily change this. The preferred way to block modules from loading is to use modprobe.blacklist=<driver>. That is what providers should be using to block specific drivers.
Drop the check to allow the driver to load even when nomodeset is specified on the kernel command line.
<<<
Why was that series never on dri-devel?
Why is this necessary in the upstream kernel? It works around a problem with the user's configuration. The series' cover letter already states the correct solution.
Firmware-only parameters affect all drivers; why not try for a common solution? At least the test against the PCI class appears useful in the common case.
Best regards Thomas
Reviewed-by: Kent Russell kent.russell@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c index f2d77bc04e4a9..7246c54bd2bbf 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c @@ -173,6 +173,7 @@ uint amdgpu_sdma_phase_quantum = 32; char *amdgpu_disable_cu; char *amdgpu_virtual_display; bool enforce_isolation; +int amdgpu_modeset = -1; /* Specifies the default granularity for SVM, used in buffer
- migration and restoration of backing memory when handling
@@ -1033,6 +1034,13 @@ module_param_named(user_partt_mode, amdgpu_user_partt_mode, uint, 0444); module_param(enforce_isolation, bool, 0444); MODULE_PARM_DESC(enforce_isolation, "enforce process isolation between graphics and compute . enforce_isolation = on"); +/**
- DOC: modeset (int)
- Override nomodeset (1 = override, -1 = auto). The default is -1 (auto).
- */
+MODULE_PARM_DESC(modeset, "Override nomodeset (1 = enable, -1 = auto)"); +module_param_named(modeset, amdgpu_modeset, int, 0444);
- /**
- DOC: seamless (int)
- Seamless boot will keep the image on the screen during the boot process.
@@ -2244,6 +2252,12 @@ static int amdgpu_pci_probe(struct pci_dev *pdev, int ret, retry = 0, i; bool supports_atomic = false;
- if ((pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA ||
(pdev->class >> 8) == PCI_CLASS_DISPLAY_OTHER) {if (drm_firmware_drivers_only() && amdgpu_modeset == -1)return -EINVAL;- }
- /* skip devices which are owned by radeon */ for (i = 0; i < ARRAY_SIZE(amdgpu_unsupported_pciidlist); i++) { if (amdgpu_unsupported_pciidlist[i] == pdev->device)