[PATCH review for 4.9 39/50] IB/hfi1: Use static CTLE with Preset 6 for integrated HFIs

[Levin, Alexander (Sasha Levin)]

From: Easwar Hariharan <easwar.hariharan@xxxxxxxxx>

[ Upstream commit 39e2afa8d042a53d855137d4c5a689a6f5492b39 ]

After extended testing, it was found that the previous PCIe Gen
3 recipe, which used adaptive CTLE with Preset 4, could cause an
NMI/Surprise Link Down in about 1 in 100 to 1 in 1000 power cycles on
some platforms. New EV data combined with extensive empirical data
indicates that the new recipe should use static CTLE with Preset 6 for
all integrated silicon SKUs.

Fixes: c3f8de0b334c ("IB/hfi1: Add static PCIe Gen3 CTLE tuning")
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx>
Signed-off-by: Easwar Hariharan <easwar.hariharan@xxxxxxxxx>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx>
Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
 drivers/infiniband/hw/hfi1/pcie.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/hw/hfi1/pcie.c b/drivers/infiniband/hw/hfi1/pcie.c
index 4ac8f330c5cb..335613a1a46a 100644
--- a/drivers/infiniband/hw/hfi1/pcie.c
+++ b/drivers/infiniband/hw/hfi1/pcie.c
@@ -673,12 +673,12 @@ MODULE_PARM_DESC(pcie_retry, "Driver will try this many times to reach requested
 
 #define UNSET_PSET 255
 #define DEFAULT_DISCRETE_PSET 2	/* discrete HFI */
-#define DEFAULT_MCP_PSET 4	/* MCP HFI */
+#define DEFAULT_MCP_PSET 6	/* MCP HFI */
 static uint pcie_pset = UNSET_PSET;
 module_param(pcie_pset, uint, S_IRUGO);
 MODULE_PARM_DESC(pcie_pset, "PCIe Eq Pset value to use, range is 0-10");
 
-static uint pcie_ctle = 1; /* discrete on, integrated off */
+static uint pcie_ctle = 3; /* discrete on, integrated on */
 module_param(pcie_ctle, uint, S_IRUGO);
 MODULE_PARM_DESC(pcie_ctle, "PCIe static CTLE mode, bit 0 - discrete on/off, bit 1 - integrated on/off");
 
-- 
2.11.0