[PATCH 08/10] arch/x86/platform/uv: BAU UV4 disable software timeout

[Andrew Banman]

Software timeouts are not currently supported on BAU for UV4. Instead, the
BAU will rely on hardware-level fairness protocols to determine broadcast
timeouts.

Do not call enable_timeouts or calculate_destination_timeout on UV4. These
functions write to pre-UV4 MMRs so they generate error messages on UV4.

Signed-off-by: Andrew Banman <abanman@xxxxxxx>
Acked-by: Mike Travis <travis@xxxxxxx>
Acked-by: Dimitri Sivanich <sivanich@xxxxxxx>
Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
 arch/x86/platform/uv/tlb_uv.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/x86/platform/uv/tlb_uv.c b/arch/x86/platform/uv/tlb_uv.c
index ddbeb16..72a5de7 100644
--- a/arch/x86/platform/uv/tlb_uv.c
+++ b/arch/x86/platform/uv/tlb_uv.c
@@ -2109,7 +2109,8 @@ static int __init init_per_cpu(int nuvhubs, int base_part_pnode)
 	void *vp;
 	struct uvhub_desc *uvhub_descs;
 
-	timeout_us = calculate_destination_timeout();
+	if (is_uv3_hub() || is_uv2_hub() || is_uv1_hub())
+		timeout_us = calculate_destination_timeout();
 
 	vp = kmalloc(nuvhubs * sizeof(struct uvhub_desc), GFP_KERNEL);
 	uvhub_descs = (struct uvhub_desc *)vp;
@@ -2171,7 +2172,9 @@ static int __init uv_bau_init(void)
 			uv_base_pnode = uv_blade_to_pnode(uvhub);
 	}
 
-	enable_timeouts();
+	/* software timeouts are not supported on UV4 */
+	if (is_uv3_hub() || is_uv2_hub() || is_uv1_hub())
+		enable_timeouts();
 
 	if (init_per_cpu(nuvhubs, uv_base_pnode)) {
 		set_bau_off();
-- 
1.8.5.6