|  | # | 
|  | # PTP clock support configuration | 
|  | # | 
|  |  | 
|  | menu "PTP clock support" | 
|  |  | 
|  | config PTP_1588_CLOCK | 
|  | tristate "PTP clock support" | 
|  | select PPS | 
|  | help | 
|  | The IEEE 1588 standard defines a method to precisely | 
|  | synchronize distributed clocks over Ethernet networks. The | 
|  | standard defines a Precision Time Protocol (PTP), which can | 
|  | be used to achieve synchronization within a few dozen | 
|  | microseconds. In addition, with the help of special hardware | 
|  | time stamping units, it can be possible to achieve | 
|  | synchronization to within a few hundred nanoseconds. | 
|  |  | 
|  | This driver adds support for PTP clocks as character | 
|  | devices. If you want to use a PTP clock, then you should | 
|  | also enable at least one clock driver as well. | 
|  |  | 
|  | To compile this driver as a module, choose M here: the module | 
|  | will be called ptp. | 
|  |  | 
|  | config PTP_1588_CLOCK_GIANFAR | 
|  | tristate "Freescale eTSEC as PTP clock" | 
|  | depends on GIANFAR | 
|  | select PTP_1588_CLOCK | 
|  | default y | 
|  | help | 
|  | This driver adds support for using the eTSEC as a PTP | 
|  | clock. This clock is only useful if your PTP programs are | 
|  | getting hardware time stamps on the PTP Ethernet packets | 
|  | using the SO_TIMESTAMPING API. | 
|  |  | 
|  | To compile this driver as a module, choose M here: the module | 
|  | will be called gianfar_ptp. | 
|  |  | 
|  | config PTP_1588_CLOCK_IXP46X | 
|  | tristate "Intel IXP46x as PTP clock" | 
|  | depends on IXP4XX_ETH | 
|  | select PTP_1588_CLOCK | 
|  | default y | 
|  | help | 
|  | This driver adds support for using the IXP46X as a PTP | 
|  | clock. This clock is only useful if your PTP programs are | 
|  | getting hardware time stamps on the PTP Ethernet packets | 
|  | using the SO_TIMESTAMPING API. | 
|  |  | 
|  | To compile this driver as a module, choose M here: the module | 
|  | will be called ptp_ixp46x. | 
|  |  | 
|  | comment "Enable PHYLIB and NETWORK_PHY_TIMESTAMPING to see the additional clocks." | 
|  | depends on PHYLIB=n || NETWORK_PHY_TIMESTAMPING=n | 
|  |  | 
|  | config DP83640_PHY | 
|  | tristate "Driver for the National Semiconductor DP83640 PHYTER" | 
|  | depends on NETWORK_PHY_TIMESTAMPING | 
|  | depends on PHYLIB | 
|  | select PTP_1588_CLOCK | 
|  | ---help--- | 
|  | Supports the DP83640 PHYTER with IEEE 1588 features. | 
|  |  | 
|  | This driver adds support for using the DP83640 as a PTP | 
|  | clock. This clock is only useful if your PTP programs are | 
|  | getting hardware time stamps on the PTP Ethernet packets | 
|  | using the SO_TIMESTAMPING API. | 
|  |  | 
|  | In order for this to work, your MAC driver must also | 
|  | implement the skb_tx_timestamp() function. | 
|  |  | 
|  | config PTP_1588_CLOCK_PCH | 
|  | tristate "Intel PCH EG20T as PTP clock" | 
|  | select PTP_1588_CLOCK | 
|  | help | 
|  | This driver adds support for using the PCH EG20T as a PTP | 
|  | clock. The hardware supports time stamping of PTP packets | 
|  | when using the end-to-end delay (E2E) mechansim. The peer | 
|  | delay mechansim (P2P) is not supported. | 
|  |  | 
|  | This clock is only useful if your PTP programs are getting | 
|  | hardware time stamps on the PTP Ethernet packets using the | 
|  | SO_TIMESTAMPING API. | 
|  |  | 
|  | To compile this driver as a module, choose M here: the module | 
|  | will be called ptp_pch. | 
|  |  | 
|  | endmenu |