TSEC: add config options for VSC8601 RGMII PHY

The Vitesse VSC8601 RGMII PHY has internal delay for both Rx
and Tx clock lines. They are configured using 2 bits in extended
register 0x17.
Therefore CFG_VSC8601_SKEW_TX and CFG_VSC8601_SKEW_RX have
been introduced with valid values 0-3 giving 0.0, 1.4,1.7 and 2.0ns delay.

Signed-off-by: Andre Schwarz <andre.schwarz@matrix-vision.de>
Acked-by: Andy Fleming <afleming@freescale.com>
Acked-by: Ben Warren <biggerbadderben@gmail.com>
--

 drivers/net/tsec.c |    6 ++++++
 drivers/net/tsec.h |    3 +++
 2 files changed, 9 insertions(+), 0 deletions(-)
diff --git a/drivers/net/tsec.c b/drivers/net/tsec.c
index 9d22aa3..f86bfd7 100644
--- a/drivers/net/tsec.c
+++ b/drivers/net/tsec.c
@@ -1277,6 +1277,12 @@
 				{MIIM_CONTROL, MIIM_CONTROL_INIT, &mii_cr_init},
 #ifdef CFG_VSC8601_SKEWFIX
 				{MIIM_VSC8601_EPHY_CON,MIIM_VSC8601_EPHY_CON_INIT_SKEW,NULL},
+if defined(CFG_VSC8601_SKEW_TX) && defined(CFG_VSC8601_SKEW_RX)
+				{MIIM_EXT_PAGE_ACCESS,1,NULL},
+#define VSC8101_SKEW	(CFG_VSC8601_SKEW_TX<<14)|(CFG_VSC8601_SKEW_RX<<12)
+				{MIIM_VSC8601_SKEW_CTRL,VSC8101_SKEW,NULL},
+				{MIIM_EXT_PAGE_ACCESS,0,NULL},
+#endif
 #endif
 				{miim_end,}
 				 },