[PATCH v3 4/4] Enabling hardware supported PTP system/device crosstimestamping
From: Christopher S. Hall
Date: Fri Aug 21 2015 - 21:53:57 EST
From: Christopher Hall <christopher.s.hall@xxxxxxxxx>
Add getsynctime() PTP device callback to cross timestamp system device
clock using ART translation depends on platform being >= SPT
and having ART
getsynctime() reads ART (TSC-derived)/device cross timestamp and
converts to realtime/device time reporting cross timestamp to
PTP driver
Signed-off-by: Christopher S. Hall <christopher.s.hall@xxxxxxxxx>
---
drivers/net/ethernet/intel/e1000e/defines.h | 5 ++
drivers/net/ethernet/intel/e1000e/ptp.c | 88 +++++++++++++++++++++++++++++
drivers/net/ethernet/intel/e1000e/regs.h | 4 ++
3 files changed, 97 insertions(+)
diff --git a/drivers/net/ethernet/intel/e1000e/defines.h b/drivers/net/ethernet/intel/e1000e/defines.h
index 133d407..13cff75 100644
--- a/drivers/net/ethernet/intel/e1000e/defines.h
+++ b/drivers/net/ethernet/intel/e1000e/defines.h
@@ -527,6 +527,11 @@
#define E1000_RXCW_C 0x20000000 /* Receive config */
#define E1000_RXCW_SYNCH 0x40000000 /* Receive config synch */
+/* HH Time Sync */
+#define E1000_TSYNCTXCTL_MAX_ALLOWED_DLY_MASK 0x0000F000 /* max delay */
+#define E1000_TSYNCTXCTL_SYNC_COMP 0x40000000 /* sync complete */
+#define E1000_TSYNCTXCTL_START_SYNC 0x80000000 /* initiate sync */
+
#define E1000_TSYNCTXCTL_VALID 0x00000001 /* Tx timestamp valid */
#define E1000_TSYNCTXCTL_ENABLED 0x00000010 /* enable Tx timestamping */
diff --git a/drivers/net/ethernet/intel/e1000e/ptp.c b/drivers/net/ethernet/intel/e1000e/ptp.c
index 25a0ad5..228f3f3 100644
--- a/drivers/net/ethernet/intel/e1000e/ptp.c
+++ b/drivers/net/ethernet/intel/e1000e/ptp.c
@@ -25,6 +25,8 @@
*/
#include "e1000.h"
+#include <asm/tsc.h>
+#include <linux/timekeeping.h>
/**
* e1000e_phc_adjfreq - adjust the frequency of the hardware clock
@@ -98,6 +100,87 @@ static int e1000e_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
return 0;
}
+#define MAX_HW_WAIT_COUNT (3)
+
+static int e1000e_phc_get_ts(struct correlated_ts *cts)
+{
+ struct e1000_adapter *adapter = (struct e1000_adapter *)cts->private;
+ struct e1000_hw *hw = &adapter->hw;
+ int i;
+ u32 tsync_ctrl;
+ int ret;
+
+ tsync_ctrl = er32(TSYNCTXCTL);
+ tsync_ctrl |= E1000_TSYNCTXCTL_START_SYNC |
+ E1000_TSYNCTXCTL_MAX_ALLOWED_DLY_MASK;
+ ew32(TSYNCTXCTL, tsync_ctrl);
+ for (i = 0; i < MAX_HW_WAIT_COUNT; ++i) {
+ udelay(1);
+ tsync_ctrl = er32(TSYNCTXCTL);
+ if (tsync_ctrl & E1000_TSYNCTXCTL_SYNC_COMP)
+ break;
+ }
+
+ if (i == MAX_HW_WAIT_COUNT) {
+ ret = -ETIMEDOUT;
+ } else {
+ ret = 0;
+ cts->system_ts = er32(PLTSTMPH);
+ cts->system_ts <<= 32;
+ cts->system_ts |= er32(PLTSTMPL);
+ cts->device_ts = er32(SYSSTMPH);
+ cts->device_ts <<= 32;
+ cts->device_ts |= er32(SYSSTMPL);
+ }
+
+ return ret;
+}
+
+/**
+ * e1000e_phc_getsynctime - Reads the current time from the hardware clock and
+ * correlated system time
+ * @ptp: ptp clock structure
+ * @devts: timespec structure to hold the current device time value
+ * @systs: timespec structure to hold the current system time value
+ *
+ * Read device and system (ART) clock simultaneously and return the correct
+ * clock values in ns after converting into a struct timespec.
+ **/
+static int e1000e_phc_getsynctime(struct ptp_clock_info *ptp,
+ struct timespec64 *devts,
+ struct timespec64 *systs)
+{
+ struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
+ ptp_clock_info);
+ unsigned long flags;
+ u32 remainder;
+ struct correlated_ts art_correlated_ts;
+ u64 device_time;
+ int ret;
+
+ art_correlated_ts.get_ts = e1000e_phc_get_ts;
+ art_correlated_ts.private = adapter;
+ ret = get_correlated_timestamp(&art_correlated_ts,
+ &art_timestamper);
+ if (ret != 0)
+ goto bail;
+
+ systs->tv_sec =
+ div_u64_rem(art_correlated_ts.system_real.tv64,
+ NSEC_PER_SEC, &remainder);
+ systs->tv_nsec = remainder;
+ spin_lock_irqsave(&adapter->systim_lock, flags);
+ device_time = timecounter_cyc2time(&adapter->tc,
+ art_correlated_ts.device_ts);
+ spin_unlock_irqrestore(&adapter->systim_lock, flags);
+ devts->tv_sec =
+ div_u64_rem(device_time, NSEC_PER_SEC, &remainder);
+ devts->tv_nsec = remainder;
+
+bail:
+ return ret;
+}
+
/**
* e1000e_phc_gettime - Reads the current time from the hardware clock
* @ptp: ptp clock structure
@@ -190,6 +273,7 @@ static const struct ptp_clock_info e1000e_ptp_clock_info = {
.adjfreq = e1000e_phc_adjfreq,
.adjtime = e1000e_phc_adjtime,
.gettime64 = e1000e_phc_gettime,
+ .getsynctime64 = e1000e_phc_getsynctime,
.settime64 = e1000e_phc_settime,
.enable = e1000e_phc_enable,
};
@@ -236,6 +320,10 @@ void e1000e_ptp_init(struct e1000_adapter *adapter)
break;
}
+ /* CPU must have ART and GBe must be from Sunrise Point or greater */
+ if (hw->mac.type < e1000_pch_spt || !cpu_has_art)
+ adapter->ptp_clock_info.getsynctime64 = NULL;
+
INIT_DELAYED_WORK(&adapter->systim_overflow_work,
e1000e_systim_overflow_work);
diff --git a/drivers/net/ethernet/intel/e1000e/regs.h b/drivers/net/ethernet/intel/e1000e/regs.h
index b24e5fe..4dd5b54 100644
--- a/drivers/net/ethernet/intel/e1000e/regs.h
+++ b/drivers/net/ethernet/intel/e1000e/regs.h
@@ -246,6 +246,10 @@
#define E1000_SYSTIML 0x0B600 /* System time register Low - RO */
#define E1000_SYSTIMH 0x0B604 /* System time register High - RO */
#define E1000_TIMINCA 0x0B608 /* Increment attributes register - RW */
+#define E1000_SYSSTMPL 0x0B648 /* HH Timesync system stamp low register */
+#define E1000_SYSSTMPH 0x0B64C /* HH Timesync system stamp hi register */
+#define E1000_PLTSTMPL 0x0B640 /* HH Timesync platform stamp low register */
+#define E1000_PLTSTMPH 0x0B644 /* HH Timesync platform stamp hi register */
#define E1000_RXMTRL 0x0B634 /* Time sync Rx EtherType and Msg Type - RW */
#define E1000_RXUDP 0x0B638 /* Time Sync Rx UDP Port - RW */
--
2.1.4
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