[Skiboot] [PATCH 2/2] phb4: Change default GEN3 lane equalisation setting to 0x54

Michael Neuling mikey at neuling.org
Wed Nov 29 11:38:21 AEDT 2017

Currently our GEN3 lane equalisation settings are set to 0x77. Change
this to 0x54. This change will allow us to train at GEN3 in a shorter
time and more consistently.

This setting gives us a TX preset 0x4 and RX hint 0x5. This gives a
boost in gain for high frequency signaling. It allows the most optimal
continuous time linear equalizers (CTLE) for the remote receiver port
and de-emphasis and pre-shoot for the remote transmitter port.

Machine Readable Workbooks (MRW) are moving to this new value also.

Signed-off-by: Michael Neuling <mikey at neuling.org>
 hw/phb4.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/hw/phb4.c b/hw/phb4.c
index 17c9e6db81..c8539c24fd 100644
--- a/hw/phb4.c
+++ b/hw/phb4.c
@@ -4843,8 +4843,8 @@ static const struct irq_source_ops phb4_lsi_ops = {
 static u64 lane_eq_default[8] = {
-	0x7777777777777777, 0x7777777777777777,
-	0x7777777777777777, 0x7777777777777777,
+	0x5454545454545454, 0x5454545454545454,
+	0x5454545454545454, 0x5454545454545454,
 	0x7777777777777777, 0x7777777777777777,
 	0x7777777777777777, 0x7777777777777777

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