Commit 4ac5617c authored by Jonathan Kim's avatar Jonathan Kim Committed by Alex Deucher
Browse files

drm/amdgpu: mask the xgmi number of hops reported from psp to kfd 



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: default avatarJonathan Kim <jonathan.kim@amd.com>
Reviewed-by: default avatarAmber Lin <amber.lin@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 9a9c59a8

drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.c

+8 −1
Original line number Diff line number Diff line
@@ -468,15 +468,22 @@ 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;

}