From 74918c858fd6c2978f272648961351c5397d0995 Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Sun, 6 Sep 2020 12:05:12 -0400 Subject: [PATCH] drm/amdgpu: Fail to load on RAVEN if SME is active MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Due to hardware bugs, scatter/gather display on raven requires a 1:1 IOMMU mapping, however, SME (System Memory Encryption) requires an indirect IOMMU mapping because the encryption bit is beyond the DMA mask of the chip. As such, the two are incompatible. Acked-by: Joerg Roedel Reviewed-by: Christian König Acked-by: Felix Kuehling Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c index 5fafb3dff1a06..52cf9488bbbff 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c @@ -1101,6 +1101,16 @@ static int amdgpu_pci_probe(struct pci_dev *pdev, return -ENODEV; } + /* Due to hardware bugs, S/G Display on raven requires a 1:1 IOMMU mapping, + * however, SME requires an indirect IOMMU mapping because the encryption + * bit is beyond the DMA mask of the chip. + */ + if (mem_encrypt_active() && ((flags & AMD_ASIC_MASK) == CHIP_RAVEN)) { + dev_info(&pdev->dev, + "SME is not compatible with RAVEN\n"); + return -ENOTSUPP; + } + #ifdef CONFIG_DRM_AMDGPU_SI if (!amdgpu_si_support) { switch (flags & AMD_ASIC_MASK) { -- 2.39.5