[PATCH 3.8 64/67] IB/qib: Add missing serdes init sequence

[Kamal Mostafa]

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

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

From: Mike Marciniszyn <mike.marciniszyn at intel.com>

commit 2f75e12c4457a9b3d042c0a0d748fa198dc2ffaf upstream.

Research has shown that commit a77fcf895046 ("IB/qib: Use a single
txselect module parameter for serdes tuning") missed a key serdes init
sequence.

This patch add that sequence.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro at intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn at intel.com>
Signed-off-by: Roland Dreier <roland at purestorage.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/infiniband/hw/qib/qib_iba7322.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/infiniband/hw/qib/qib_iba7322.c b/drivers/infiniband/hw/qib/qib_iba7322.c
index bd8cb0f..14103ff 100644
--- a/drivers/infiniband/hw/qib/qib_iba7322.c
+++ b/drivers/infiniband/hw/qib/qib_iba7322.c
@@ -2287,6 +2287,11 @@ static int qib_7322_bringup_serdes(struct qib_pportdata *ppd)
 	qib_write_kreg_port(ppd, krp_ibcctrl_a, ppd->cpspec->ibcctrl_a);
 	qib_write_kreg(dd, kr_scratch, 0ULL);
 
+	/* ensure previous Tx parameters are not still forced */
+	qib_write_kreg_port(ppd, krp_tx_deemph_override,
+		SYM_MASK(IBSD_TX_DEEMPHASIS_OVERRIDE_0,
+		reset_tx_deemphasis_override));
+
 	if (qib_compat_ddr_negotiate) {
 		ppd->cpspec->ibdeltainprog = 1;
 		ppd->cpspec->ibsymsnap = read_7322_creg32_port(ppd,
-- 
1.8.3.2