On Wed, May 11, 2022 at 2:20 PM Lyude Paul <lyude@xxxxxxxxxx> wrote: > > Many DRM drivers feature a 'modeset' argument, which can be used to > enable/disable the entire driver (as opposed to passing nomodeset to the > kernel, which would disable modesetting globally and make it difficult to > load amdgpu afterwards). Apparently amdgpu is actually missing this > however, so let's add it! You can already do that by passing modprobe.blacklist=amdgpu on the kernel command line. I don't think we need another option to do that. > > Keep in mind that this currently just lets one enable or disable amdgpu, I > haven't bothered adding a headless mode like nouveau has - however I'm sure > someone else can add this if needed. You can do this as well by passing an IP block mask which disables the display IP, or media IP, etc. Alex > > Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx> > --- > 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 ebd37fb19cdb..24e6fb4517cc 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > @@ -872,6 +872,15 @@ MODULE_PARM_DESC(smu_pptable_id, > "specify pptable id to be used (-1 = auto(default) value, 0 = use pptable from vbios, > 0 = soft pptable id)"); > module_param_named(smu_pptable_id, amdgpu_smu_pptable_id, int, 0444); > > +/** > + * DOC: modeset (int) > + * Used to enable/disable modesetting for amdgpu exclusively. > + */ > +bool amdgpu_enable_modeset = true; > +MODULE_PARM_DESC(modeset, > + "Enable or disable display driver (1 = on (default), 0 = off"); > +module_param_named(modeset, amdgpu_enable_modeset, bool, 0444); > + > /* These devices are not supported by amdgpu. > * They are supported by the mach64, r128, radeon drivers > */ > @@ -2003,6 +2012,11 @@ static int amdgpu_pci_probe(struct pci_dev *pdev, > bool is_fw_fb; > resource_size_t base, size; > > + if (!amdgpu_enable_modeset) { > + DRM_INFO("modeset=0 passed to amdgpu, driver will not be enabled\n"); > + return -ENODEV; > + } > + > /* skip devices which are owned by radeon */ > for (i = 0; i < ARRAY_SIZE(amdgpu_unsupported_pciidlist); i++) { > if (amdgpu_unsupported_pciidlist[i] == pdev->device) > -- > 2.35.1 >