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@xxxxxxxxxxxxxx>
Sinan, I guess Christian's suggestion is to add amdgpu_device_init function
like here:
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
--
To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
