cpts: introduce time stamping code and a PTP hardware clock.

This patch adds a driver for the CPTS that offers time
stamping and a PTP hardware clock. Because some of the
CPTS hardware variants (like the am335x) do not support
frequency adjustment, we have implemented this in software
by changing the multiplication factor of the timecounter.

Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/ti/Kconfig

@@ -60,6 +60,14 @@ config TI_CPSW
 	  To compile this driver as a module, choose M here: the module
 	  will be called cpsw.
 
+config TI_CPTS
+	boolean "TI Common Platform Time Sync (CPTS) Support"
+	depends on TI_CPSW && PTP_1588_CLOCK && !(TI_CPSW=y && PTP_1588_CLOCK=m)
+	---help---
+	  This driver supports the Common Platform Time Sync unit of
+	  the CPSW Ethernet Switch. The unit can time stamp PTP UDP/IPv4
+	  and Layer 2 packets, and the driver offers a PTP Hardware Clock.
+
 config TLAN
 	tristate "TI ThunderLAN support"
 	depends on (PCI || EISA)

drivers/net/ethernet/ti/Makefile

@@ -8,4 +8,4 @@ obj-$(CONFIG_TI_DAVINCI_EMAC) += davinci_emac.o
 obj-$(CONFIG_TI_DAVINCI_MDIO) += davinci_mdio.o
 obj-$(CONFIG_TI_DAVINCI_CPDMA) += davinci_cpdma.o
 obj-$(CONFIG_TI_CPSW) += ti_cpsw.o
-ti_cpsw-y := cpsw_ale.o cpsw.o
+ti_cpsw-y := cpsw_ale.o cpsw.o cpts.o