x86/platform/uv/BAU: Fix payload queue setup on UV4 hardware

[cascardo/linux.git] / arch / x86 / platform / uv / tlb_uv.c

diff --git a/arch/x86/platform/uv/tlb_uv.c b/arch/x86/platform/uv/tlb_uv.c
index 72a5de7..7ca0e5c 100644 (file)
--- a/arch/x86/platform/uv/tlb_uv.c
+++ b/arch/x86/platform/uv/tlb_uv.c
@@ -1826,11 +1826,19 @@ static void pq_init(int node, int pnode)
 
        first = ops.bau_gpa_to_offset(uv_gpa(pqp));
        last = ops.bau_gpa_to_offset(uv_gpa(pqp + (DEST_Q_SIZE - 1)));
-       tail = first;
-       gnode = uv_gpa_to_gnode(uv_gpa(pqp));
-       first = (gnode << UV_PAYLOADQ_GNODE_SHIFT) | tail;
 
-       write_mmr_payload_tail(pnode, tail);
+       /*
+        * Pre UV4, the gnode is required to locate the payload queue
+        * and the payload queue tail must be maintained by the kernel.
+        */
+       bcp = &per_cpu(bau_control, smp_processor_id());
+       if (bcp->uvhub_version <= 3) {
+               tail = first;
+               gnode = uv_gpa_to_gnode(uv_gpa(pqp));
+               first = (gnode << UV_PAYLOADQ_GNODE_SHIFT) | tail;
+               write_mmr_payload_tail(pnode, tail);
+       }
+
        ops.write_payload_first(pnode, first);
        ops.write_payload_last(pnode, last);
        ops.write_g_sw_ack(pnode, 0xffffUL);