net: ethernet: altera_tse: add support for SGMII PCS

Add support for the (optional) SGMII PCS functionality of the Altera
TSE MAC. If the phy-mode is set to 'sgmii' then we attempt to discover
and initialise the PCS so that the MAC can communicate to the PHY.

The PCS IP block provides a scratch register for testing presence of
the PCS, which is mapped into one of the two MDIO spaces present in
the MAC's register space.  Once we have determined that the scratch
register is functioning, we attempt to initialise the PCS to
auto-negotiate an SGMII link with the PHY. There is no need to monitor
or manage the SGMII link beyond this, since the normal PHY MDIO will
then be used to monitor the media layer.

The Altera TSE MAC has only one way in which it can be configured with an
SGMII PCS, and as such, this patch only looks to the phy-mode to select
whether or not to attempt to initialise the PCS registers.  During
initialisation, we report the PCS's equivalent of a PHY ID register.
This can be parameterised during the IP instantiation and is often left
as '0x00000000' which is not an error.

Signed-off-by: Neill Whillans <neill.whillans@codethink.co.uk>
Reviewed-by: Daniel Silverstone <daniel.silverstone@codethink.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/net/ethernet/altera/altera_tse.h b/drivers/net/ethernet/altera/altera_tse.h
index 9b640c8fbc28..e2feee87180a 100644
--- a/drivers/net/ethernet/altera/altera_tse.h
+++ b/drivers/net/ethernet/altera/altera_tse.h
@@ -120,6 +120,17 @@
 #define MAC_CMDCFG_DISABLE_READ_TIMEOUT_GET(v)	GET_BIT_VALUE(v, 27)
 #define MAC_CMDCFG_CNT_RESET_GET(v)		GET_BIT_VALUE(v, 31)
 
+/* SGMII PCS register addresses
+ */
+#define SGMII_PCS_SCRATCH	0x10
+#define SGMII_PCS_REV		0x11
+#define SGMII_PCS_LINK_TIMER_0	0x12
+#define SGMII_PCS_LINK_TIMER_1	0x13
+#define SGMII_PCS_IF_MODE	0x14
+#define SGMII_PCS_DIS_READ_TO	0x15
+#define SGMII_PCS_READ_TO	0x16
+#define SGMII_PCS_SW_RESET_TIMEOUT 100 /* usecs */
+
 /* MDIO registers within MAC register Space
  */
 struct altera_tse_mdio {