[PATCH 4.9 40/51] IB/hfi1: Use static CTLE with Preset 6 for integrated HFIs

From: Greg Kroah-Hartman
Date: Thu Oct 19 2017 - 10:17:14 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/infiniband/hw/hfi1/pcie.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/infiniband/hw/hfi1/pcie.c
+++ b/drivers/infiniband/hw/hfi1/pcie.c
@@ -673,12 +673,12 @@ MODULE_PARM_DESC(pcie_retry, "Driver wil

#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");