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path: root/drivers/net/ethernet/intel/ice/ice_ptp.c
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2021-06-17ice: remove unnecessary NULL checks before ptp_read_system_*Jacob Keller
The ptp_read_system_prets and ptp_read_system_postts functions already check for the NULL value of the ptp_system_timestamp structure pointer. There is no need to check this manually in the ice driver code. Remove the checks. Reported-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2021-06-11ice: enable transmit timestamps for E810 devicesJacob Keller
Add support for enabling Tx timestamp requests for outgoing packets on E810 devices. The ice hardware can support multiple outstanding Tx timestamp requests. When sending a descriptor to hardware, a Tx timestamp request is made by setting a request bit, and assigning an index that represents which Tx timestamp index to store the timestamp in. Hardware makes no effort to synchronize the index use, so it is up to software to ensure that Tx timestamp indexes are not re-used before the timestamp is reported back. To do this, introduce a Tx timestamp tracker which will keep track of currently in-use indexes. In the hot path, if a packet has a timestamp request, an index will be requested from the tracker. Unfortunately, this does require a lock as the indexes are shared across all queues on a PHY. There are not enough indexes to reliably assign only 1 to each queue. For the E810 devices, the timestamp indexes are not shared across PHYs, so each port can have its own tracking. Once hardware captures a timestamp, an interrupt is fired. In this interrupt, trigger a new work item that will figure out which timestamp was completed, and report the timestamp back to the stack. This function loops through the Tx timestamp indexes and checks whether there is now a valid timestamp. If so, it clears the PHY timestamp indication in the PHY memory, locks and removes the SKB and bit in the tracker, then reports the timestamp to the stack. It is possible in some cases that a timestamp request will be initiated but never completed. This might occur if the packet is dropped by software or hardware before it reaches the PHY. Add a task to the periodic work function that will check whether a timestamp request is more than a few seconds old. If so, the timestamp index is cleared in the PHY, and the SKB is released. Just as with Rx timestamps, the Tx timestamps are only 40 bits wide, and use the same overall logic for extending to 64 bits of nanoseconds. With this change, E810 devices should be able to perform basic PTP functionality. Future changes will extend the support to cover the E822-based devices. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Tested-by: Tony Brelinski <tonyx.brelinski@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2021-06-11ice: enable receive hardware timestampingJacob Keller
Add SIOCGHWTSTAMP and SIOCSHWTSTAMP ioctl handlers to respond to requests to enable timestamping support. If the request is for enabling Rx timestamps, set a bit in the Rx descriptors to indicate that receive timestamps should be reported. Hardware captures receive timestamps in the PHY which only captures part of the timer, and reports only 40 bits into the Rx descriptor. The upper 32 bits represent the contents of GLTSYN_TIME_L at the point of packet reception, while the lower 8 bits represent the upper 8 bits of GLTSYN_TIME_0. The networking and PTP stack expect 64 bit timestamps in nanoseconds. To support this, implement some logic to extend the timestamps by using the full PHC time. If the Rx timestamp was captured prior to the PHC time, then the real timestamp is PHC - (lower_32_bits(PHC) - timestamp) If the Rx timestamp was captured after the PHC time, then the real timestamp is PHC + (timestamp - lower_32_bits(PHC)) These calculations are correct as long as neither the PHC timestamp nor the Rx timestamps are more than 2^32-1 nanseconds old. Further, we can detect when the Rx timestamp is before or after the PHC as long as the PHC timestamp is no more than 2^31-1 nanoseconds old. In that case, we calculate the delta between the lower 32 bits of the PHC and the Rx timestamp. If it's larger than 2^31-1 then the Rx timestamp must have been captured in the past. If it's smaller, then the Rx timestamp must have been captured after PHC time. Add an ice_ptp_extend_32b_ts function that relies on a cached copy of the PHC time and implements this algorithm to calculate the proper upper 32bits of the Rx timestamps. Cache the PHC time periodically in all of the Rx rings. This enables each Rx ring to simply call the extension function with a recent copy of the PHC time. By ensuring that the PHC time is kept up to date periodically, we ensure this algorithm doesn't use stale data and produce incorrect results. To cache the time, introduce a kworker and a kwork item to periodically store the Rx time. It might seem like we should use the .do_aux_work interface of the PTP clock. This doesn't work because all PFs must cache this time, but only one PF owns the PTP clock device. Thus, the ice driver will manage its own kthread instead of relying on the PTP do_aux_work handler. With this change, the driver can now report Rx timestamps on all incoming packets. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Tested-by: Tony Brelinski <tonyx.brelinski@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2021-06-11ice: report the PTP clock index in ethtool .get_ts_infoJacob Keller
Now that the driver registers a PTP clock device that represents the clock hardware, it is important that the clock index is reported via the ethtool .get_ts_info callback. The underlying hardware resource is shared between multiple PF functions. Only one function owns the hardware resources associated with a timer, but multiple functions may be associated with it for the purposes of timestamping. To support this, the owning PF will store the clock index into the driver shared parameters buffer in firmware. Other PFs will look up the clock index by reading the driver shared parameter on demand when requested via the .get_ts_info ethtool function. In this way, all functions which are tied to the same timer are able to report the clock index. Userspace software such as ptp4l performs a look up on the netdev to determine the associated clock, and all commands to control or configure the clock will be handled through the controlling PF. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Tested-by: Tony Brelinski <tonyx.brelinski@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2021-06-11ice: register 1588 PTP clock device object for E810 devicesJacob Keller
Add a new ice_ptp.c file for holding the basic PTP clock interface functions. If the device supports PTP, call the new ice_ptp_init and ice_ptp_release functions where appropriate. If the function owns the hardware resource associated with the PTP hardware clock, register with the PTP_1588_CLOCK infrastructure to allocate a new clock object that represents the device hardware clock. Implement basic functionality for reading and setting the clock time, performing clock adjustments, and adjusting the clock frequency. Future changes will introduce functionality for handling related features including Tx and Rx timestamps. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Tested-by: Tony Brelinski <tonyx.brelinski@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>