Am 11.04.2018 um 08:26 schrieb Huang Rui:
On Tue, Apr 10, 2018 at 04:59:55PM -0400, Sinan Kaya wrote:
Code is expecing to observe the same number of buffers returned from dma_map_sg() function compared to sg_alloc_table_from_pages(). This doesn't hold true universally especially for systems with IOMMU.
IOMMU driver tries to combine buffers into a single DMA address as much as it can. The right thing is to tell the DMA layer how much combining IOMMU can do.
Signed-off-by: Sinan Kaya okaya@codeaurora.org
Sinan, I guess Christian's suggestion is to add amdgpu_device_init function like here:
Yes, exactly. Looks like Sinan just tried to place the call next to pci_set_dma_mask()/pci_set_consistent_dma_mask().
Not necessary a bad idea, but in this case not optimal.
Sinan please refine your patch as Rui suggested and resend.
Thanks, Christian.
8<------- diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c index 0e798b3..9b96771 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c @@ -2339,6 +2339,8 @@ int amdgpu_device_init(struct amdgpu_device *adev, /* init the mode config */ drm_mode_config_init(adev->ddev);
dma_set_max_seg_size(adev->dev, PAGE_SIZE);r = amdgpu_device_ip_init(adev); if (r) { /* failed in exclusive mode due to timeout */8<-------
After that, we don't do it in each generation.
Thanks, Ray _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel