i40e: extend PTP gettime function to read system clock

This adds support for the PTP_SYS_OFFSET_EXTENDED ioctl.

Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Acked-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e_ptp.c

@@ -28,19 +28,23 @@
  * i40e_ptp_read - Read the PHC time from the device
  * @pf: Board private structure
  * @ts: timespec structure to hold the current time value
+ * @sts: structure to hold the system time before and after reading the PHC
  *
  * This function reads the PRTTSYN_TIME registers and stores them in a
  * timespec. However, since the registers are 64 bits of nanoseconds, we must
  * convert the result to a timespec before we can return.
  **/
-static void i40e_ptp_read(struct i40e_pf *pf, struct timespec64 *ts)
+static void i40e_ptp_read(struct i40e_pf *pf, struct timespec64 *ts,
+			  struct ptp_system_timestamp *sts)
 {
 	struct i40e_hw *hw = &pf->hw;
 	u32 hi, lo;
 	u64 ns;
 
 	/* The timer latches on the lowest register read. */
+	ptp_read_system_prets(sts);
 	lo = rd32(hw, I40E_PRTTSYN_TIME_L);
+	ptp_read_system_postts(sts);
 	hi = rd32(hw, I40E_PRTTSYN_TIME_H);
 
 	ns = (((u64)hi) << 32) | lo;
@@ -146,7 +150,7 @@ static int i40e_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
 
 	mutex_lock(&pf->tmreg_lock);
 
-	i40e_ptp_read(pf, &now);
+	i40e_ptp_read(pf, &now, NULL);
 	timespec64_add_ns(&now, delta);
 	i40e_ptp_write(pf, (const struct timespec64 *)&now);
 
@@ -156,19 +160,21 @@ static int i40e_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
 }
 
 /**
- * i40e_ptp_gettime - Get the time of the PHC
+ * i40e_ptp_gettimex - Get the time of the PHC
  * @ptp: The PTP clock structure
  * @ts: timespec structure to hold the current time value
+ * @sts: structure to hold the system time before and after reading the PHC
  *
  * Read the device clock and return the correct value on ns, after converting it
  * into a timespec struct.
  **/
-static int i40e_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
+static int i40e_ptp_gettimex(struct ptp_clock_info *ptp, struct timespec64 *ts,
+			     struct ptp_system_timestamp *sts)
 {
 	struct i40e_pf *pf = container_of(ptp, struct i40e_pf, ptp_caps);
 
 	mutex_lock(&pf->tmreg_lock);
-	i40e_ptp_read(pf, ts);
+	i40e_ptp_read(pf, ts, sts);
 	mutex_unlock(&pf->tmreg_lock);
 
 	return 0;
@@ -702,7 +708,7 @@ static long i40e_ptp_create_clock(struct i40e_pf *pf)
 	pf->ptp_caps.pps = 0;
 	pf->ptp_caps.adjfreq = i40e_ptp_adjfreq;
 	pf->ptp_caps.adjtime = i40e_ptp_adjtime;
-	pf->ptp_caps.gettime64 = i40e_ptp_gettime;
+	pf->ptp_caps.gettimex64 = i40e_ptp_gettimex;
 	pf->ptp_caps.settime64 = i40e_ptp_settime;
 	pf->ptp_caps.enable = i40e_ptp_feature_enable;