drm/msm/mdp4: stop supporting no-IOMMU configuration

With the switch to GPUVM the msm driver no longer supports the no-IOMMU
configurations (even without the actual GPU). Return an error in case we
face the lack of the IOMMU for an MDP4 device.

Fixes: 111fdd2198e6 ("drm/msm: drm_gpuvm conversion")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/672557/
Signed-off-by: Rob Clark <robin.clark@oss.qualcomm.com>

diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
index 0952c7f18abdca4a7e24e5af8a7132456bfec129..4d1ea9b2619170335ab4d2a2ee46f31e785b2c02 100644 (file)
--- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
+++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
@@ -463,9 +463,9 @@ static int mdp4_kms_init(struct drm_device *dev)
                ret = PTR_ERR(mmu);
                goto fail;
        } else if (!mmu) {
-               DRM_DEV_INFO(dev->dev, "no iommu, fallback to phys "
-                               "contig buffers for scanout\n");
-               vm = NULL;
+               DRM_DEV_INFO(dev->dev, "no IOMMU, bailing out\n");
+               ret = -ENODEV;
+               goto fail;
        } else {
                vm  = msm_gem_vm_create(dev, mmu, "mdp4",
                                        0x1000, 0x100000000 - 0x1000,