This is a note to let you know that I've just added the patch titled drm/amdgpu: mask the xgmi number of hops reported from psp to kfd to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-amdgpu-mask-the-xgmi-number-of-hops-reported-fro.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 91d1e0cdf136d24b93b7c3f7eb9afb2c8f8439d8 Author: Jonathan Kim <jonathan.kim@xxxxxxx> Date: Wed Jan 27 15:24:59 2021 -0500 drm/amdgpu: mask the xgmi number of hops reported from psp to kfd [ Upstream commit 4ac5617c4b7d0f0a8f879997f8ceaa14636d7554 ] The psp supplies the link type in the upper 2 bits of the psp xgmi node information num_hops field. With a new link type, Aldebaran has these bits set to a non-zero value (1 = xGMI3) so the KFD topology will report the incorrect IO link weights without proper masking. The actual number of hops is located in the 3 least significant bits of this field so mask if off accordingly before passing it to the KFD. Signed-off-by: Jonathan Kim <jonathan.kim@xxxxxxx> Reviewed-by: Amber Lin <amber.lin@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.c index 1162913c8bf4..0526dec1d736 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.c @@ -465,15 +465,22 @@ int amdgpu_xgmi_update_topology(struct amdgpu_hive_info *hive, struct amdgpu_dev } +/* + * NOTE psp_xgmi_node_info.num_hops layout is as follows: + * num_hops[7:6] = link type (0 = xGMI2, 1 = xGMI3, 2/3 = reserved) + * num_hops[5:3] = reserved + * num_hops[2:0] = number of hops + */ int amdgpu_xgmi_get_hops_count(struct amdgpu_device *adev, struct amdgpu_device *peer_adev) { struct psp_xgmi_topology_info *top = &adev->psp.xgmi_context.top_info; + uint8_t num_hops_mask = 0x7; int i; for (i = 0 ; i < top->num_nodes; ++i) if (top->nodes[i].node_id == peer_adev->gmc.xgmi.node_id) - return top->nodes[i].num_hops; + return top->nodes[i].num_hops & num_hops_mask; return -EINVAL; }