[PATCH net-next v3 00/11] net: ethernet: ti: cpts: add irq and HW_TS_PUSH events

[PATCH net-next v3 00/11] net: ethernet: ti: cpts: add irq and HW_TS_PUSH events

[Grygorii Strashko]

Hi Richard, All,

This is re-spin of patches to add CPSW IRQ and HW_TS_PUSH events support I've
sent long time ago [1]. In this series, I've tried to restructure and split changes,
and also add few additional optimizations comparing to initial RFC submission [1].

The HW_TS_PUSH events intended to serve for different timesync purposes on of
which is to add PPS generation function, which can be implemented as below:

                     +-----------------+
                     | Control         |
                     | application     |
            +------->+                 +----------+
            |        |                 |          |
            |        |                 |          |
            |        +-----------------+          |
            |                                     |
            |                                     |
            | PTP_EXTTS_REQUEST                   |
            |                                     |
            |                                     |
 +----------------------------------------------------------------+
            |                                     |    Kernel
    +-------+----------+                  +-------v--------+
    |  \dev\ptpX       |                  | /sys/class/pwm/|
    |                  |                  |                |
    +-------^----------+                  +-------+--------+
            |                                     |
            |                                     |
            |                             +-------v-------------------+
    +-------+----------+                  |                           |
    | CPTS driver      |                  |pwm/pwm-omap-dmtimer.c     |
    |                  |                  +---------------------------+
    +-------^----------+                  |clocksource/timer_ti_dm.c  |
            |                             +-------+-------------------+
            |HWx_TS_PUSH evt                      |
 +----------------------------------------------------------------+
            |                                     |         HW
    +-------+----------+                  +-------v--------+
    | CPTS             |                  | DMTimer        |
    |                  |                  |                |
    |      HWx_TS_PUSH X<-----------------+                |
    |                  +                  |                |
    +------------------+                  +-------+--------+
                                                  |
                                                  X timer4


As per my knowledge there is at least one public implemented above PPS generation
schema from Tusori Tibor [2] based on initial HW_TS_PUSH enable submission[1].
And now there is work done by Lokesh Vutla <lokeshvutla@ti.com> published to
enable PWM enable/improve PWM adjustment from user space [3][4][5].

Main changes comparing to initial submission:
- both RX/TX timestamp processing deferred to ptp worker
- both CPTS IRQ and polling events processing supported to make it work for
  Keystone 2 also
- switch to use new .gettimex64() interface
- no DT updates as number of HWx_TS_PUSH inputs is static per HW

Dependency:
 ff7cf1822b93 kthread: mark timer used by delayed kthread works as IRQ safe
 which was merged in -next, but has to be back-ported for testing with earlier
 versions

Testing on am571x-idk/omap2plus_defconfig/+CONFIG_PREEMPT=y:
1) testing HW_TS_PUSH
 - enable pwm in DT
	pwm16: dmtimer-pwm {
		compatible = "ti,omap-dmtimer-pwm";
		ti,timers = <&timer16>;
		#pwm-cells = <3>;
	};
 - configure and start pwm
  echo 0 > /sys/class/pwm/pwmchip0/export                                                                          
  echo 1000000000 > /sys/class/pwm/pwmchip0/pwm0/period                                                            
  echo 500000000 > /sys/class/pwm/pwmchip0/pwm0/duty_cycle                                                         
  echo 1 > /sys/class/pwm/pwmchip0/pwm0/enable   
 - test HWx_TS_PUSH using Kernel selftest testptp application
  ./tools/testing/selftests/ptp/testptp -d /dev/ptp0 -e 1000 -i 3

2) testing phc2sys
# ./linuxptp/phc2sys -s CLOCK_REALTIME -c eth0 -m -O 0 -u30                                            
phc2sys[1616.791]: eth0 rms 408190379792180864 max 1580914543017209856 freq +864 +/- 4635 delay 645 +/- 29
phc2sys[1646.795]: eth0 rms 41 max 108 freq +0 +/- 36 delay 656 +/- 29
phc2sys[1676.800]: eth0 rms 43 max 83 freq +2 +/- 38 delay 650 +/- 0
phc2sys[1706.804]: eth0 rms 39 max 87 freq +4 +/- 34 delay 672 +/- 55
phc2sys[1736.808]: eth0 rms 35 max 66 freq +1 +/- 30 delay 667 +/- 49
phc2sys[1766.813]: eth0 rms 38 max 79 freq +2 +/- 33 delay 656 +/- 29
phc2sys[1796.817]: eth0 rms 45 max 98 freq +1 +/- 39 delay 656 +/- 29
phc2sys[1826.821]: eth0 rms 40 max 87 freq +5 +/- 35 delay 650 +/- 0
phc2sys[1856.826]: eth0 rms 29 max 76 freq -0 +/- 25 delay 656 +/- 29
phc2sys[1886.830]: eth0 rms 40 max 97 freq +4 +/- 35 delay 667 +/- 49
phc2sys[1916.834]: eth0 rms 42 max 94 freq +2 +/- 36 delay 661 +/- 41
phc2sys[1946.839]: eth0 rms 40 max 91 freq +2 +/- 35 delay 661 +/- 41
phc2sys[1976.843]: eth0 rms 46 max 88 freq -0 +/- 40 delay 667 +/- 49
phc2sys[2006.847]: eth0 rms 49 max 97 freq +2 +/- 43 delay 650 +/- 0

3) testing ptp4l
- 1G connection
# ./linuxptp/ptp4l -P -2 -H -i eth0 -l 6 -m -q -p /dev/ptp0 -f ptp.cfg -s                              
ptp4l[862.891]: port 1: UNCALIBRATED to SLAVE on MASTER_CLOCK_SELECTED
ptp4l[923.894]: rms 1019697354682 max 5768279314068 freq +26053 +/- 72 delay 488 +/- 1
ptp4l[987.896]: rms 13 max 26 freq +26005 +/- 29 delay 488 +/- 1
ptp4l[1051.899]: rms 14 max 50 freq +25895 +/- 21 delay 488 +/- 1
ptp4l[1115.901]: rms 11 max 27 freq +25878 +/- 17 delay 488 +/- 1
ptp4l[1179.904]: rms 10 max 27 freq +25857 +/- 12 delay 488 +/- 1
ptp4l[1243.906]: rms 14 max 37 freq +25851 +/- 15 delay 488 +/- 1
ptp4l[1307.909]: rms 12 max 33 freq +25835 +/- 15 delay 488 +/- 1
ptp4l[1371.911]: rms 11 max 27 freq +25832 +/- 14 delay 488 +/- 1
ptp4l[1435.914]: rms 11 max 26 freq +25823 +/- 11 delay 488 +/- 1
ptp4l[1499.916]: rms 10 max 29 freq +25829 +/- 11 delay 489 +/- 1
ptp4l[1563.919]: rms 11 max 27 freq +25827 +/- 12 delay 488 +/- 1

- 10M connection
# ./linuxptp/ptp4l -P -2 -H -i eth0 -l 6 -m -q -p /dev/ptp0 -f ptp.cfg -s                              
ptp4l[51.955]: port 1: UNCALIBRATED to SLAVE on MASTER_CLOCK_SELECTED
ptp4l[112.957]: rms 279468848453933920 max 1580914542977391360 freq +25390 +/- 3207 delay 8222 +/- 36
ptp4l[176.960]: rms 254 max 522 freq +25809 +/- 219 delay 8271 +/- 30
ptp4l[240.962]: rms 271 max 684 freq +25868 +/- 234 delay 8249 +/- 22
ptp4l[304.965]: rms 263 max 556 freq +25894 +/- 227 delay 8225 +/- 47
ptp4l[368.967]: rms 238 max 648 freq +25908 +/- 204 delay 8234 +/- 40
ptp4l[432.970]: rms 274 max 658 freq +25932 +/- 237 delay 8241 +/- 22
ptp4l[496.972]: rms 247 max 557 freq +25943 +/- 213 delay 8223 +/- 26
ptp4l[560.974]: rms 291 max 756 freq +25968 +/- 251 delay 8244 +/- 41
ptp4l[624.977]: rms 249 max 697 freq +25975 +/- 216 delay 8258 +/- 22

Changes in v3:
 - fixed rebase mess
 - fixed build issues

Changes in v2 (broken):
 - fixed (formatting) comments from David Miller <davem@davemloft.net>

v2: https://patchwork.ozlabs.org/cover/1258339/
v1: https://patchwork.ozlabs.org/cover/1254708/

[1] https://lore.kernel.org/patchwork/cover/799251/
[2] https://usermanual.wiki/Document/SetupGuide.632280828.pdf
    https://github.com/t-tibor/msc_thesis
[3] https://patchwork.kernel.org/cover/11421329/
[4] https://patchwork.kernel.org/cover/11433197/
[5] https://sourceforge.net/p/linuxptp/mailman/message/36943248/

Grygorii Strashko (11):
  net: ethernet: ti: cpts: use dev_yy() api for logs
  net: ethernet: ti: cpts: separate hw counter read from timecounter
  net: ethernet: ti: cpts: move tc mult update in cpts_fifo_read()
  net: ethernet: ti: cpts: switch to use new .gettimex64() interface
  net: ethernet: ti: cpts: optimize packet to event matching
  net: ethernet: ti: cpts: move tx timestamp processing to ptp worker
    only
  net: ethernet: ti: cpts: rework locking
  net: ethernet: ti: cpts: move rx timestamp processing to ptp worker
    only
  net: ethernet: ti: cpts: add irq support
  net: ethernet: ti: cpts: add support for HW_TS_PUSH events
  net: ethernet: ti: cpsw: enable cpts irq

 drivers/net/ethernet/ti/cpsw.c        |  35 +-
 drivers/net/ethernet/ti/cpsw_new.c    |  33 +-
 drivers/net/ethernet/ti/cpsw_priv.c   |  17 +-
 drivers/net/ethernet/ti/cpsw_priv.h   |   2 +
 drivers/net/ethernet/ti/cpts.c        | 508 +++++++++++++++++---------
 drivers/net/ethernet/ti/cpts.h        |  33 +-
 drivers/net/ethernet/ti/netcp_ethss.c |   3 +-
 7 files changed, 447 insertions(+), 184 deletions(-)

-- 
2.17.1

[PATCH net-next v3 01/11] net: ethernet: ti: cpts: use dev_yy() api for logs

[Grygorii Strashko]

Use dev_yy() API instead of pr_yy() for log outputs.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpts.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 729ce09dded9..f07b40504e5b 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -71,7 +71,7 @@ static int cpts_purge_events(struct cpts *cpts)
 	}
 
 	if (removed)
-		pr_debug("cpts: event pool cleaned up %d\n", removed);
+		dev_dbg(cpts->dev, "cpts: event pool cleaned up %d\n", removed);
 	return removed ? 0 : -1;
 }
 
@@ -150,7 +150,7 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 			break;
 
 		if (list_empty(&cpts->pool) && cpts_purge_events(cpts)) {
-			pr_err("cpts: event pool empty\n");
+			dev_info(cpts->dev, "cpts: event pool empty\n");
 			return -1;
 		}
 
@@ -178,7 +178,7 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 		case CPTS_EV_HW:
 			break;
 		default:
-			pr_err("cpts: unknown event type\n");
+			dev_err(cpts->dev, "cpts: unknown event type\n");
 			break;
 		}
 		if (type == match)
@@ -196,7 +196,7 @@ static u64 cpts_systim_read(const struct cyclecounter *cc)
 
 	cpts_write32(cpts, TS_PUSH, ts_push);
 	if (cpts_fifo_read(cpts, CPTS_EV_PUSH))
-		pr_err("cpts: unable to obtain a time stamp\n");
+		dev_err(cpts->dev, "cpts: unable to obtain a time stamp\n");
 
 	list_for_each_safe(this, next, &cpts->events) {
 		event = list_entry(this, struct cpts_event, list);
@@ -307,8 +307,8 @@ static long cpts_overflow_check(struct ptp_clock_info *ptp)
 	}
 	spin_unlock_irqrestore(&cpts->lock, flags);
 
-	pr_debug("cpts overflow check at %lld.%09ld\n",
-		 (long long)ts.tv_sec, ts.tv_nsec);
+	dev_dbg(cpts->dev, "cpts overflow check at %lld.%09ld\n",
+		(long long)ts.tv_sec, ts.tv_nsec);
 	return (long)delay;
 }
 
-- 
2.17.1

[PATCH net-next v3 02/11] net: ethernet: ti: cpts: separate hw counter read from timecounter

[Grygorii Strashko]

Separate hw counter read from timecounter code:
- add CPTS context field to store current HW counter value
- move HW timestamp request and FIFO read code out of timecounter code
- convert cyc2time on event reception in cpts_fifo_read()
- call timecounter_read() in cpts_fifo_read() to update tk->cycle_last

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpts.c | 53 +++++++++++++++++-----------------
 drivers/net/ethernet/ti/cpts.h |  2 ++
 2 files changed, 29 insertions(+), 26 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index f07b40504e5b..6a1844cd23ff 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -112,10 +112,8 @@ static bool cpts_match_tx_ts(struct cpts *cpts, struct cpts_event *event)
 					(struct cpts_skb_cb_data *)skb->cb;
 
 		if (cpts_match(skb, class, seqid, mtype)) {
-			u64 ns = timecounter_cyc2time(&cpts->tc, event->low);
-
 			memset(&ssh, 0, sizeof(ssh));
-			ssh.hwtstamp = ns_to_ktime(ns);
+			ssh.hwtstamp = ns_to_ktime(event->timestamp);
 			skb_tstamp_tx(skb, &ssh);
 			found = true;
 			__skb_unlink(skb, &cpts->txq);
@@ -158,8 +156,16 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 		event->tmo = jiffies + 2;
 		event->high = hi;
 		event->low = lo;
+		event->timestamp = timecounter_cyc2time(&cpts->tc, event->low);
 		type = event_type(event);
+
+		dev_dbg(cpts->dev, "CPTS_EV: %d high:%08X low:%08x\n",
+			type, event->high, event->low);
 		switch (type) {
+		case CPTS_EV_PUSH:
+			WRITE_ONCE(cpts->cur_timestamp, lo);
+			timecounter_read(&cpts->tc);
+			break;
 		case CPTS_EV_TX:
 			if (cpts_match_tx_ts(cpts, event)) {
 				/* if the new event matches an existing skb,
@@ -168,7 +174,6 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 				break;
 			}
 			/* fall through */
-		case CPTS_EV_PUSH:
 		case CPTS_EV_RX:
 			list_del_init(&event->list);
 			list_add_tail(&event->list, &cpts->events);
@@ -189,26 +194,17 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 
 static u64 cpts_systim_read(const struct cyclecounter *cc)
 {
-	u64 val = 0;
-	struct cpts_event *event;
-	struct list_head *this, *next;
 	struct cpts *cpts = container_of(cc, struct cpts, cc);
 
-	cpts_write32(cpts, TS_PUSH, ts_push);
-	if (cpts_fifo_read(cpts, CPTS_EV_PUSH))
-		dev_err(cpts->dev, "cpts: unable to obtain a time stamp\n");
+	return READ_ONCE(cpts->cur_timestamp);
+}
 
-	list_for_each_safe(this, next, &cpts->events) {
-		event = list_entry(this, struct cpts_event, list);
-		if (event_type(event) == CPTS_EV_PUSH) {
-			list_del_init(&event->list);
-			list_add(&event->list, &cpts->pool);
-			val = event->low;
-			break;
-		}
-	}
+static void cpts_update_cur_time(struct cpts *cpts, int match)
+{
+	cpts_write32(cpts, TS_PUSH, ts_push);
 
-	return val;
+	if (cpts_fifo_read(cpts, match) && match != -1)
+		dev_err(cpts->dev, "cpts: unable to obtain a time stamp\n");
 }
 
 /* PTP clock operations */
@@ -232,7 +228,7 @@ static int cpts_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
 
 	spin_lock_irqsave(&cpts->lock, flags);
 
-	timecounter_read(&cpts->tc);
+	cpts_update_cur_time(cpts, CPTS_EV_PUSH);
 
 	cpts->cc.mult = neg_adj ? mult - diff : mult + diff;
 
@@ -260,6 +256,9 @@ static int cpts_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
 	struct cpts *cpts = container_of(ptp, struct cpts, info);
 
 	spin_lock_irqsave(&cpts->lock, flags);
+
+	cpts_update_cur_time(cpts, CPTS_EV_PUSH);
+
 	ns = timecounter_read(&cpts->tc);
 	spin_unlock_irqrestore(&cpts->lock, flags);
 
@@ -294,11 +293,14 @@ static long cpts_overflow_check(struct ptp_clock_info *ptp)
 {
 	struct cpts *cpts = container_of(ptp, struct cpts, info);
 	unsigned long delay = cpts->ov_check_period;
-	struct timespec64 ts;
 	unsigned long flags;
+	u64 ns;
 
 	spin_lock_irqsave(&cpts->lock, flags);
-	ts = ns_to_timespec64(timecounter_read(&cpts->tc));
+
+	cpts_update_cur_time(cpts, -1);
+
+	ns = timecounter_read(&cpts->tc);
 
 	if (!skb_queue_empty(&cpts->txq)) {
 		cpts_purge_txq(cpts);
@@ -307,8 +309,7 @@ static long cpts_overflow_check(struct ptp_clock_info *ptp)
 	}
 	spin_unlock_irqrestore(&cpts->lock, flags);
 
-	dev_dbg(cpts->dev, "cpts overflow check at %lld.%09ld\n",
-		(long long)ts.tv_sec, ts.tv_nsec);
+	dev_dbg(cpts->dev, "cpts overflow check at %lld\n", ns);
 	return (long)delay;
 }
 
@@ -390,7 +391,7 @@ static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type)
 		seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK;
 		if (ev_type == event_type(event) &&
 		    cpts_match(skb, class, seqid, mtype)) {
-			ns = timecounter_cyc2time(&cpts->tc, event->low);
+			ns = event->timestamp;
 			list_del_init(&event->list);
 			list_add(&event->list, &cpts->pool);
 			break;
diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h
index bb997c11ee15..32ecd1ce4d3b 100644
--- a/drivers/net/ethernet/ti/cpts.h
+++ b/drivers/net/ethernet/ti/cpts.h
@@ -94,6 +94,7 @@ struct cpts_event {
 	unsigned long tmo;
 	u32 high;
 	u32 low;
+	u64 timestamp;
 };
 
 struct cpts {
@@ -114,6 +115,7 @@ struct cpts {
 	struct cpts_event pool_data[CPTS_MAX_EVENTS];
 	unsigned long ov_check_period;
 	struct sk_buff_head txq;
+	u64 cur_timestamp;
 };
 
 void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb);
-- 
2.17.1

[PATCH net-next v3 03/11] net: ethernet: ti: cpts: move tc mult update in cpts_fifo_read()

[Grygorii Strashko]

Now CPTS driver .adjfreq() generates request to read CPTS current time
(CPTS_EV_PUSH) with intention to process all pending event using previous
frequency adjustment values before switching to the new ones. So
CPTS_EV_PUSH works as a marker to switch to the new frequency adjustment
values. Current code assumes that all job is done in .adjfreq(), but after
enabling IRQ this will not be true any more.

Hence save new frequency adjustment values (mult) and perform actual freq
adjustment in cpts_fifo_read() immediately after CPTS_EV_PUSH is received.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpts.c | 8 ++++++--
 drivers/net/ethernet/ti/cpts.h | 1 +
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 6a1844cd23ff..e6a8ccae711c 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -165,6 +165,10 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 		case CPTS_EV_PUSH:
 			WRITE_ONCE(cpts->cur_timestamp, lo);
 			timecounter_read(&cpts->tc);
+			if (cpts->mult_new) {
+				cpts->cc.mult = cpts->mult_new;
+				cpts->mult_new = 0;
+			}
 			break;
 		case CPTS_EV_TX:
 			if (cpts_match_tx_ts(cpts, event)) {
@@ -228,9 +232,9 @@ static int cpts_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
 
 	spin_lock_irqsave(&cpts->lock, flags);
 
-	cpts_update_cur_time(cpts, CPTS_EV_PUSH);
+	cpts->mult_new = neg_adj ? mult - diff : mult + diff;
 
-	cpts->cc.mult = neg_adj ? mult - diff : mult + diff;
+	cpts_update_cur_time(cpts, CPTS_EV_PUSH);
 
 	spin_unlock_irqrestore(&cpts->lock, flags);
 
diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h
index 32ecd1ce4d3b..421630049ee7 100644
--- a/drivers/net/ethernet/ti/cpts.h
+++ b/drivers/net/ethernet/ti/cpts.h
@@ -116,6 +116,7 @@ struct cpts {
 	unsigned long ov_check_period;
 	struct sk_buff_head txq;
 	u64 cur_timestamp;
+	u32 mult_new;
 };
 
 void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb);
-- 
2.17.1

[PATCH net-next v3 04/11] net: ethernet: ti: cpts: switch to use new .gettimex64() interface

[Grygorii Strashko]

The CPTS HW latches and saves CPTS counter value in CPTS fifo immediately
after writing to CPSW_CPTS_PUSH.TS_PUSH (bit 0), so the total time that the
driver needs to read the CPTS timestamp is the time required CPSW_CPTS_PUSH
write to actually reach HW.

Hence switch CPTS driver to implement new .gettimex64() callback for more
precise measurement of the offset between a PHC and the system clock which
is measured as time between
  write(CPSW_CPTS_PUSH)
  read(CPSW_CPTS_PUSH)

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpts.c | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index e6a8ccae711c..7e4c1de0d207 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -203,9 +203,13 @@ static u64 cpts_systim_read(const struct cyclecounter *cc)
 	return READ_ONCE(cpts->cur_timestamp);
 }
 
-static void cpts_update_cur_time(struct cpts *cpts, int match)
+static void cpts_update_cur_time(struct cpts *cpts, int match,
+				 struct ptp_system_timestamp *sts)
 {
+	ptp_read_system_prets(sts);
 	cpts_write32(cpts, TS_PUSH, ts_push);
+	cpts_read32(cpts, ts_push);
+	ptp_read_system_postts(sts);
 
 	if (cpts_fifo_read(cpts, match) && match != -1)
 		dev_err(cpts->dev, "cpts: unable to obtain a time stamp\n");
@@ -234,7 +238,7 @@ static int cpts_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
 
 	cpts->mult_new = neg_adj ? mult - diff : mult + diff;
 
-	cpts_update_cur_time(cpts, CPTS_EV_PUSH);
+	cpts_update_cur_time(cpts, CPTS_EV_PUSH, NULL);
 
 	spin_unlock_irqrestore(&cpts->lock, flags);
 
@@ -253,15 +257,17 @@ static int cpts_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
 	return 0;
 }
 
-static int cpts_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
+static int cpts_ptp_gettimeex(struct ptp_clock_info *ptp,
+			      struct timespec64 *ts,
+			      struct ptp_system_timestamp *sts)
 {
-	u64 ns;
-	unsigned long flags;
 	struct cpts *cpts = container_of(ptp, struct cpts, info);
+	unsigned long flags;
+	u64 ns;
 
 	spin_lock_irqsave(&cpts->lock, flags);
 
-	cpts_update_cur_time(cpts, CPTS_EV_PUSH);
+	cpts_update_cur_time(cpts, CPTS_EV_PUSH, sts);
 
 	ns = timecounter_read(&cpts->tc);
 	spin_unlock_irqrestore(&cpts->lock, flags);
@@ -302,7 +308,7 @@ static long cpts_overflow_check(struct ptp_clock_info *ptp)
 
 	spin_lock_irqsave(&cpts->lock, flags);
 
-	cpts_update_cur_time(cpts, -1);
+	cpts_update_cur_time(cpts, -1, NULL);
 
 	ns = timecounter_read(&cpts->tc);
 
@@ -326,7 +332,7 @@ static const struct ptp_clock_info cpts_info = {
 	.pps		= 0,
 	.adjfreq	= cpts_ptp_adjfreq,
 	.adjtime	= cpts_ptp_adjtime,
-	.gettime64	= cpts_ptp_gettime,
+	.gettimex64	= cpts_ptp_gettimeex,
 	.settime64	= cpts_ptp_settime,
 	.enable		= cpts_ptp_enable,
 	.do_aux_work	= cpts_overflow_check,
-- 
2.17.1

[PATCH net-next v3 05/11] net: ethernet: ti: cpts: optimize packet to event matching

[Grygorii Strashko]

Now the CPTS driver performs packet (skb) parsing every time when it needs
to match packet to CPTS event (including ptp_classify_raw() calls).

This patch optimizes matching process by parsing packet only once upon
arrival and stores PTP specific data in skb->cb using the same fromat as in
CPTS HW event. As result, all future matching reduces to comparing two u32
values.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpts.c | 91 ++++++++++++++++++++++------------
 1 file changed, 58 insertions(+), 33 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 7e4c1de0d207..f7ce482ad09c 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -23,15 +23,13 @@
 #define CPTS_SKB_TX_WORK_TIMEOUT 1 /* jiffies */
 
 struct cpts_skb_cb_data {
+	u32 skb_mtype_seqid;
 	unsigned long tmo;
 };
 
 #define cpts_read32(c, r)	readl_relaxed(&c->reg->r)
 #define cpts_write32(c, v, r)	writel_relaxed(v, &c->reg->r)
 
-static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
-		      u16 ts_seqid, u8 ts_msgtype);
-
 static int event_expired(struct cpts_event *event)
 {
 	return time_after(jiffies, event->tmo);
@@ -97,29 +95,29 @@ static void cpts_purge_txq(struct cpts *cpts)
 static bool cpts_match_tx_ts(struct cpts *cpts, struct cpts_event *event)
 {
 	struct sk_buff *skb, *tmp;
-	u16 seqid;
-	u8 mtype;
 	bool found = false;
+	u32 mtype_seqid;
 
-	mtype = (event->high >> MESSAGE_TYPE_SHIFT) & MESSAGE_TYPE_MASK;
-	seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK;
+	mtype_seqid = event->high &
+		      ((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
+		       (SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
+		       (EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
 
 	/* no need to grab txq.lock as access is always done under cpts->lock */
 	skb_queue_walk_safe(&cpts->txq, skb, tmp) {
 		struct skb_shared_hwtstamps ssh;
-		unsigned int class = ptp_classify_raw(skb);
 		struct cpts_skb_cb_data *skb_cb =
 					(struct cpts_skb_cb_data *)skb->cb;
 
-		if (cpts_match(skb, class, seqid, mtype)) {
+		if (mtype_seqid == skb_cb->skb_mtype_seqid) {
 			memset(&ssh, 0, sizeof(ssh));
 			ssh.hwtstamp = ns_to_ktime(event->timestamp);
 			skb_tstamp_tx(skb, &ssh);
 			found = true;
 			__skb_unlink(skb, &cpts->txq);
 			dev_consume_skb_any(skb);
-			dev_dbg(cpts->dev, "match tx timestamp mtype %u seqid %04x\n",
-				mtype, seqid);
+			dev_dbg(cpts->dev, "match tx timestamp mtype_seqid %08x\n",
+				mtype_seqid);
 			break;
 		}
 
@@ -338,12 +336,15 @@ static const struct ptp_clock_info cpts_info = {
 	.do_aux_work	= cpts_overflow_check,
 };
 
-static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
-		      u16 ts_seqid, u8 ts_msgtype)
+static int cpts_skb_get_mtype_seqid(struct sk_buff *skb, u32 *mtype_seqid)
 {
-	u16 *seqid;
-	unsigned int offset = 0;
+	unsigned int ptp_class = ptp_classify_raw(skb);
 	u8 *msgtype, *data = skb->data;
+	unsigned int offset = 0;
+	u16 *seqid;
+
+	if (ptp_class == PTP_CLASS_NONE)
+		return 0;
 
 	if (ptp_class & PTP_CLASS_VLAN)
 		offset += VLAN_HLEN;
@@ -371,22 +372,20 @@ static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
 		msgtype = data + offset;
 
 	seqid = (u16 *)(data + offset + OFF_PTP_SEQUENCE_ID);
+	*mtype_seqid = (*msgtype & MESSAGE_TYPE_MASK) << MESSAGE_TYPE_SHIFT;
+	*mtype_seqid |= (ntohs(*seqid) & SEQUENCE_ID_MASK) << SEQUENCE_ID_SHIFT;
 
-	return (ts_msgtype == (*msgtype & 0xf) && ts_seqid == ntohs(*seqid));
+	return 1;
 }
 
-static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type)
+static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb,
+			int ev_type, u32 skb_mtype_seqid)
 {
-	u64 ns = 0;
-	struct cpts_event *event;
 	struct list_head *this, *next;
-	unsigned int class = ptp_classify_raw(skb);
+	struct cpts_event *event;
 	unsigned long flags;
-	u16 seqid;
-	u8 mtype;
-
-	if (class == PTP_CLASS_NONE)
-		return 0;
+	u32 mtype_seqid;
+	u64 ns = 0;
 
 	spin_lock_irqsave(&cpts->lock, flags);
 	cpts_fifo_read(cpts, -1);
@@ -397,10 +396,13 @@ static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type)
 			list_add(&event->list, &cpts->pool);
 			continue;
 		}
-		mtype = (event->high >> MESSAGE_TYPE_SHIFT) & MESSAGE_TYPE_MASK;
-		seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK;
-		if (ev_type == event_type(event) &&
-		    cpts_match(skb, class, seqid, mtype)) {
+
+		mtype_seqid = event->high &
+			      ((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
+			       (SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
+			       (EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
+
+		if (mtype_seqid == skb_mtype_seqid) {
 			ns = event->timestamp;
 			list_del_init(&event->list);
 			list_add(&event->list, &cpts->pool);
@@ -427,10 +429,21 @@ static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type)
 
 void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
-	u64 ns;
+	struct cpts_skb_cb_data *skb_cb = (struct cpts_skb_cb_data *)skb->cb;
 	struct skb_shared_hwtstamps *ssh;
+	int ret;
+	u64 ns;
+
+	ret = cpts_skb_get_mtype_seqid(skb, &skb_cb->skb_mtype_seqid);
+	if (!ret)
+		return;
+
+	skb_cb->skb_mtype_seqid |= (CPTS_EV_RX << EVENT_TYPE_SHIFT);
 
-	ns = cpts_find_ts(cpts, skb, CPTS_EV_RX);
+	dev_dbg(cpts->dev, "%s mtype seqid %08x\n",
+		__func__, skb_cb->skb_mtype_seqid);
+
+	ns = cpts_find_ts(cpts, skb, CPTS_EV_RX, skb_cb->skb_mtype_seqid);
 	if (!ns)
 		return;
 	ssh = skb_hwtstamps(skb);
@@ -441,12 +454,24 @@ EXPORT_SYMBOL_GPL(cpts_rx_timestamp);
 
 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
-	u64 ns;
+	struct cpts_skb_cb_data *skb_cb = (struct cpts_skb_cb_data *)skb->cb;
 	struct skb_shared_hwtstamps ssh;
+	int ret;
+	u64 ns;
 
 	if (!(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
 		return;
-	ns = cpts_find_ts(cpts, skb, CPTS_EV_TX);
+
+	ret = cpts_skb_get_mtype_seqid(skb, &skb_cb->skb_mtype_seqid);
+	if (!ret)
+		return;
+
+	skb_cb->skb_mtype_seqid |= (CPTS_EV_TX << EVENT_TYPE_SHIFT);
+
+	dev_dbg(cpts->dev, "%s mtype seqid %08x\n",
+		__func__, skb_cb->skb_mtype_seqid);
+
+	ns = cpts_find_ts(cpts, skb, CPTS_EV_TX, skb_cb->skb_mtype_seqid);
 	if (!ns)
 		return;
 	memset(&ssh, 0, sizeof(ssh));
-- 
2.17.1

[PATCH net-next v3 06/11] net: ethernet: ti: cpts: move tx timestamp processing to ptp worker only

[Grygorii Strashko]

Now the tx timestamp processing happens from different contexts - softirq
and thread/PTP worker. Enabling IRQ will add one more hard_irq context.
This makes over all defered TX timestamp processing and locking
overcomplicated. Move tx timestamp processing to PTP worker always instead.

napi_rx->cpts_tx_timestamp
 if ptp_packet then
    push to txq
    ptp_schedule_worker()

do_aux_work->cpts_overflow_check
 cpts_process_events()

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpts.c | 165 +++++++++++++++++++--------------
 1 file changed, 94 insertions(+), 71 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index f7ce482ad09c..10061e17d7b4 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -21,6 +21,8 @@
 #include "cpts.h"
 
 #define CPTS_SKB_TX_WORK_TIMEOUT 1 /* jiffies */
+#define CPTS_SKB_RX_TX_TMO 100 /*ms */
+#define CPTS_EVENT_RX_TX_TIMEOUT (100) /* ms */
 
 struct cpts_skb_cb_data {
 	u32 skb_mtype_seqid;
@@ -92,46 +94,6 @@ static void cpts_purge_txq(struct cpts *cpts)
 		dev_dbg(cpts->dev, "txq cleaned up %d\n", removed);
 }
 
-static bool cpts_match_tx_ts(struct cpts *cpts, struct cpts_event *event)
-{
-	struct sk_buff *skb, *tmp;
-	bool found = false;
-	u32 mtype_seqid;
-
-	mtype_seqid = event->high &
-		      ((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
-		       (SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
-		       (EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
-
-	/* no need to grab txq.lock as access is always done under cpts->lock */
-	skb_queue_walk_safe(&cpts->txq, skb, tmp) {
-		struct skb_shared_hwtstamps ssh;
-		struct cpts_skb_cb_data *skb_cb =
-					(struct cpts_skb_cb_data *)skb->cb;
-
-		if (mtype_seqid == skb_cb->skb_mtype_seqid) {
-			memset(&ssh, 0, sizeof(ssh));
-			ssh.hwtstamp = ns_to_ktime(event->timestamp);
-			skb_tstamp_tx(skb, &ssh);
-			found = true;
-			__skb_unlink(skb, &cpts->txq);
-			dev_consume_skb_any(skb);
-			dev_dbg(cpts->dev, "match tx timestamp mtype_seqid %08x\n",
-				mtype_seqid);
-			break;
-		}
-
-		if (time_after(jiffies, skb_cb->tmo)) {
-			/* timeout any expired skbs over 1s */
-			dev_dbg(cpts->dev, "expiring tx timestamp from txq\n");
-			__skb_unlink(skb, &cpts->txq);
-			dev_consume_skb_any(skb);
-		}
-	}
-
-	return found;
-}
-
 /*
  * Returns zero if matching event type was found.
  */
@@ -151,7 +113,6 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 		}
 
 		event = list_first_entry(&cpts->pool, struct cpts_event, list);
-		event->tmo = jiffies + 2;
 		event->high = hi;
 		event->low = lo;
 		event->timestamp = timecounter_cyc2time(&cpts->tc, event->low);
@@ -169,14 +130,10 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 			}
 			break;
 		case CPTS_EV_TX:
-			if (cpts_match_tx_ts(cpts, event)) {
-				/* if the new event matches an existing skb,
-				 * then don't queue it
-				 */
-				break;
-			}
-			/* fall through */
 		case CPTS_EV_RX:
+			event->tmo = jiffies +
+				msecs_to_jiffies(CPTS_EVENT_RX_TX_TIMEOUT);
+
 			list_del_init(&event->list);
 			list_add_tail(&event->list, &cpts->events);
 			break;
@@ -297,6 +254,84 @@ static int cpts_ptp_enable(struct ptp_clock_info *ptp,
 	return -EOPNOTSUPP;
 }
 
+static bool cpts_match_tx_ts(struct cpts *cpts, struct cpts_event *event)
+{
+	struct sk_buff_head txq_list;
+	struct sk_buff *skb, *tmp;
+	unsigned long flags;
+	bool found = false;
+	u32 mtype_seqid;
+
+	mtype_seqid = event->high &
+		      ((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
+		       (SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
+		       (EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
+
+	__skb_queue_head_init(&txq_list);
+
+	spin_lock_irqsave(&cpts->txq.lock, flags);
+	skb_queue_splice_init(&cpts->txq, &txq_list);
+	spin_unlock_irqrestore(&cpts->txq.lock, flags);
+
+	skb_queue_walk_safe(&txq_list, skb, tmp) {
+		struct skb_shared_hwtstamps ssh;
+		struct cpts_skb_cb_data *skb_cb =
+					(struct cpts_skb_cb_data *)skb->cb;
+
+		if (mtype_seqid == skb_cb->skb_mtype_seqid) {
+			memset(&ssh, 0, sizeof(ssh));
+			ssh.hwtstamp = ns_to_ktime(event->timestamp);
+			skb_tstamp_tx(skb, &ssh);
+			found = true;
+			__skb_unlink(skb, &txq_list);
+			dev_consume_skb_any(skb);
+			dev_dbg(cpts->dev, "match tx timestamp mtype_seqid %08x\n",
+				mtype_seqid);
+			break;
+		}
+
+		if (time_after(jiffies, skb_cb->tmo)) {
+			/* timeout any expired skbs over 1s */
+			dev_dbg(cpts->dev, "expiring tx timestamp from txq\n");
+			__skb_unlink(skb, &txq_list);
+			dev_consume_skb_any(skb);
+		}
+	}
+
+	spin_lock_irqsave(&cpts->txq.lock, flags);
+	skb_queue_splice(&txq_list, &cpts->txq);
+	spin_unlock_irqrestore(&cpts->txq.lock, flags);
+
+	return found;
+}
+
+static void cpts_process_events(struct cpts *cpts)
+{
+	struct list_head *this, *next;
+	struct cpts_event *event;
+	LIST_HEAD(events_free);
+	unsigned long flags;
+	LIST_HEAD(events);
+
+	spin_lock_irqsave(&cpts->lock, flags);
+	list_splice_init(&cpts->events, &events);
+	spin_unlock_irqrestore(&cpts->lock, flags);
+
+	list_for_each_safe(this, next, &events) {
+		event = list_entry(this, struct cpts_event, list);
+		if (cpts_match_tx_ts(cpts, event) ||
+		    time_after(jiffies, event->tmo)) {
+			list_del_init(&event->list);
+			list_add(&event->list, &events_free);
+		}
+	}
+
+	spin_lock_irqsave(&cpts->lock, flags);
+	list_splice_tail(&events, &cpts->events);
+	list_splice_tail(&events_free, &cpts->pool);
+	spin_unlock_irqrestore(&cpts->lock, flags);
+}
+
 static long cpts_overflow_check(struct ptp_clock_info *ptp)
 {
 	struct cpts *cpts = container_of(ptp, struct cpts, info);
@@ -305,17 +340,20 @@ static long cpts_overflow_check(struct ptp_clock_info *ptp)
 	u64 ns;
 
 	spin_lock_irqsave(&cpts->lock, flags);
-
 	cpts_update_cur_time(cpts, -1, NULL);
+	spin_unlock_irqrestore(&cpts->lock, flags);
 
 	ns = timecounter_read(&cpts->tc);
 
+	cpts_process_events(cpts);
+
+	spin_lock_irqsave(&cpts->txq.lock, flags);
 	if (!skb_queue_empty(&cpts->txq)) {
 		cpts_purge_txq(cpts);
 		if (!skb_queue_empty(&cpts->txq))
 			delay = CPTS_SKB_TX_WORK_TIMEOUT;
 	}
-	spin_unlock_irqrestore(&cpts->lock, flags);
+	spin_unlock_irqrestore(&cpts->txq.lock, flags);
 
 	dev_dbg(cpts->dev, "cpts overflow check at %lld\n", ns);
 	return (long)delay;
@@ -409,19 +447,6 @@ static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb,
 			break;
 		}
 	}
-
-	if (ev_type == CPTS_EV_TX && !ns) {
-		struct cpts_skb_cb_data *skb_cb =
-				(struct cpts_skb_cb_data *)skb->cb;
-		/* Not found, add frame to queue for processing later.
-		 * The periodic FIFO check will handle this.
-		 */
-		skb_get(skb);
-		/* get the timestamp for timeouts */
-		skb_cb->tmo = jiffies + msecs_to_jiffies(100);
-		__skb_queue_tail(&cpts->txq, skb);
-		ptp_schedule_worker(cpts->clock, 0);
-	}
 	spin_unlock_irqrestore(&cpts->lock, flags);
 
 	return ns;
@@ -455,9 +480,7 @@ EXPORT_SYMBOL_GPL(cpts_rx_timestamp);
 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
 	struct cpts_skb_cb_data *skb_cb = (struct cpts_skb_cb_data *)skb->cb;
-	struct skb_shared_hwtstamps ssh;
 	int ret;
-	u64 ns;
 
 	if (!(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
 		return;
@@ -471,12 +494,12 @@ void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 	dev_dbg(cpts->dev, "%s mtype seqid %08x\n",
 		__func__, skb_cb->skb_mtype_seqid);
 
-	ns = cpts_find_ts(cpts, skb, CPTS_EV_TX, skb_cb->skb_mtype_seqid);
-	if (!ns)
-		return;
-	memset(&ssh, 0, sizeof(ssh));
-	ssh.hwtstamp = ns_to_ktime(ns);
-	skb_tstamp_tx(skb, &ssh);
+	/* Always defer TX TS processing to PTP worker */
+	skb_get(skb);
+	/* get the timestamp for timeouts */
+	skb_cb->tmo = jiffies + msecs_to_jiffies(CPTS_SKB_RX_TX_TMO);
+	skb_queue_tail(&cpts->txq, skb);
+	ptp_schedule_worker(cpts->clock, 0);
 }
 EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
 
-- 
2.17.1

[PATCH net-next v3 07/11] net: ethernet: ti: cpts: rework locking

[Grygorii Strashko]

Now spinlock is used to synchronize everything which is not required. Add
mutex and use to sync access to PTP interface and PTP worker and use
spinlock only to sync FIFO/events processing.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpts.c | 53 +++++++++++++++++++---------------
 drivers/net/ethernet/ti/cpts.h |  3 +-
 2 files changed, 32 insertions(+), 24 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 10061e17d7b4..3cfa0f78287b 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -99,9 +99,12 @@ static void cpts_purge_txq(struct cpts *cpts)
  */
 static int cpts_fifo_read(struct cpts *cpts, int match)
 {
+	struct cpts_event *event;
+	unsigned long flags;
 	int i, type = -1;
 	u32 hi, lo;
-	struct cpts_event *event;
+
+	spin_lock_irqsave(&cpts->lock, flags);
 
 	for (i = 0; i < CPTS_FIFO_DEPTH; i++) {
 		if (cpts_fifo_pop(cpts, &hi, &lo))
@@ -109,7 +112,7 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 
 		if (list_empty(&cpts->pool) && cpts_purge_events(cpts)) {
 			dev_info(cpts->dev, "cpts: event pool empty\n");
-			return -1;
+			break;
 		}
 
 		event = list_first_entry(&cpts->pool, struct cpts_event, list);
@@ -148,6 +151,9 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 		if (type == match)
 			break;
 	}
+
+	spin_unlock_irqrestore(&cpts->lock, flags);
+
 	return type == match ? 0 : -1;
 }
 
@@ -161,10 +167,15 @@ static u64 cpts_systim_read(const struct cyclecounter *cc)
 static void cpts_update_cur_time(struct cpts *cpts, int match,
 				 struct ptp_system_timestamp *sts)
 {
+	unsigned long flags;
+
+	/* use spin_lock_irqsave() here as it has to run very fast */
+	spin_lock_irqsave(&cpts->lock, flags);
 	ptp_read_system_prets(sts);
 	cpts_write32(cpts, TS_PUSH, ts_push);
 	cpts_read32(cpts, ts_push);
 	ptp_read_system_postts(sts);
+	spin_unlock_irqrestore(&cpts->lock, flags);
 
 	if (cpts_fifo_read(cpts, match) && match != -1)
 		dev_err(cpts->dev, "cpts: unable to obtain a time stamp\n");
@@ -174,11 +185,10 @@ static void cpts_update_cur_time(struct cpts *cpts, int match,
 
 static int cpts_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
 {
-	u64 adj;
-	u32 diff, mult;
-	int neg_adj = 0;
-	unsigned long flags;
 	struct cpts *cpts = container_of(ptp, struct cpts, info);
+	int neg_adj = 0;
+	u32 diff, mult;
+	u64 adj;
 
 	if (ppb < 0) {
 		neg_adj = 1;
@@ -189,25 +199,23 @@ static int cpts_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
 	adj *= ppb;
 	diff = div_u64(adj, 1000000000ULL);
 
-	spin_lock_irqsave(&cpts->lock, flags);
+	mutex_lock(&cpts->ptp_clk_mutex);
 
 	cpts->mult_new = neg_adj ? mult - diff : mult + diff;
 
 	cpts_update_cur_time(cpts, CPTS_EV_PUSH, NULL);
 
-	spin_unlock_irqrestore(&cpts->lock, flags);
-
+	mutex_unlock(&cpts->ptp_clk_mutex);
 	return 0;
 }
 
 static int cpts_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
 {
-	unsigned long flags;
 	struct cpts *cpts = container_of(ptp, struct cpts, info);
 
-	spin_lock_irqsave(&cpts->lock, flags);
+	mutex_lock(&cpts->ptp_clk_mutex);
 	timecounter_adjtime(&cpts->tc, delta);
-	spin_unlock_irqrestore(&cpts->lock, flags);
+	mutex_unlock(&cpts->ptp_clk_mutex);
 
 	return 0;
 }
@@ -217,15 +225,14 @@ static int cpts_ptp_gettimeex(struct ptp_clock_info *ptp,
 			      struct ptp_system_timestamp *sts)
 {
 	struct cpts *cpts = container_of(ptp, struct cpts, info);
-	unsigned long flags;
 	u64 ns;
 
-	spin_lock_irqsave(&cpts->lock, flags);
+	mutex_lock(&cpts->ptp_clk_mutex);
 
 	cpts_update_cur_time(cpts, CPTS_EV_PUSH, sts);
 
 	ns = timecounter_read(&cpts->tc);
-	spin_unlock_irqrestore(&cpts->lock, flags);
+	mutex_unlock(&cpts->ptp_clk_mutex);
 
 	*ts = ns_to_timespec64(ns);
 
@@ -235,15 +242,14 @@ static int cpts_ptp_gettimeex(struct ptp_clock_info *ptp,
 static int cpts_ptp_settime(struct ptp_clock_info *ptp,
 			    const struct timespec64 *ts)
 {
-	u64 ns;
-	unsigned long flags;
 	struct cpts *cpts = container_of(ptp, struct cpts, info);
+	u64 ns;
 
 	ns = timespec64_to_ns(ts);
 
-	spin_lock_irqsave(&cpts->lock, flags);
+	mutex_lock(&cpts->ptp_clk_mutex);
 	timecounter_init(&cpts->tc, &cpts->cc, ns);
-	spin_unlock_irqrestore(&cpts->lock, flags);
+	mutex_unlock(&cpts->ptp_clk_mutex);
 
 	return 0;
 }
@@ -339,10 +345,9 @@ static long cpts_overflow_check(struct ptp_clock_info *ptp)
 	unsigned long flags;
 	u64 ns;
 
-	spin_lock_irqsave(&cpts->lock, flags);
-	cpts_update_cur_time(cpts, -1, NULL);
-	spin_unlock_irqrestore(&cpts->lock, flags);
+	mutex_lock(&cpts->ptp_clk_mutex);
 
+	cpts_update_cur_time(cpts, -1, NULL);
 	ns = timecounter_read(&cpts->tc);
 
 	cpts_process_events(cpts);
@@ -356,6 +361,7 @@ static long cpts_overflow_check(struct ptp_clock_info *ptp)
 	spin_unlock_irqrestore(&cpts->txq.lock, flags);
 
 	dev_dbg(cpts->dev, "cpts overflow check at %lld\n", ns);
+	mutex_unlock(&cpts->ptp_clk_mutex);
 	return (long)delay;
 }
 
@@ -425,8 +431,8 @@ static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb,
 	u32 mtype_seqid;
 	u64 ns = 0;
 
-	spin_lock_irqsave(&cpts->lock, flags);
 	cpts_fifo_read(cpts, -1);
+	spin_lock_irqsave(&cpts->lock, flags);
 	list_for_each_safe(this, next, &cpts->events) {
 		event = list_entry(this, struct cpts_event, list);
 		if (event_expired(event)) {
@@ -703,6 +709,7 @@ struct cpts *cpts_create(struct device *dev, void __iomem *regs,
 	cpts->dev = dev;
 	cpts->reg = (struct cpsw_cpts __iomem *)regs;
 	spin_lock_init(&cpts->lock);
+	mutex_init(&cpts->ptp_clk_mutex);
 
 	ret = cpts_of_parse(cpts, node);
 	if (ret)
diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h
index 421630049ee7..f16e14d67f5f 100644
--- a/drivers/net/ethernet/ti/cpts.h
+++ b/drivers/net/ethernet/ti/cpts.h
@@ -104,7 +104,7 @@ struct cpts {
 	int rx_enable;
 	struct ptp_clock_info info;
 	struct ptp_clock *clock;
-	spinlock_t lock; /* protects time registers */
+	spinlock_t lock; /* protects fifo/events */
 	u32 cc_mult; /* for the nominal frequency */
 	struct cyclecounter cc;
 	struct timecounter tc;
@@ -117,6 +117,7 @@ struct cpts {
 	struct sk_buff_head txq;
 	u64 cur_timestamp;
 	u32 mult_new;
+	struct mutex ptp_clk_mutex; /* sync PTP interface and worker */
 };
 
 void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb);
-- 
2.17.1

[PATCH net-next v3 08/11] net: ethernet: ti: cpts: move rx timestamp processing to ptp worker only

[Grygorii Strashko]

Once CPTS IRQ will be enabled the CPTS irq handler may compete with netif
RX sofirq path and so RX timestamp might not be ready at the moment packet
is processed. As result, packet has to be deferred and processed later.

This patch moves RX timestamp processing tx timestamp processing to PTP
worker always the same way as it's been done for TX timestamps.

  napi_rx->cpts_rx_timestamp
   if ptp_packet then
      push to rxq
      ptp_schedule_worker()

  do_aux_work->cpts_overflow_check
    cpts_process_events()

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpsw.c     |  14 +--
 drivers/net/ethernet/ti/cpsw_new.c |  13 ++-
 drivers/net/ethernet/ti/cpts.c     | 132 ++++++++++++++++++-----------
 drivers/net/ethernet/ti/cpts.h     |   6 +-
 4 files changed, 106 insertions(+), 59 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index c2c5bf87da01..ce2155394830 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -433,17 +433,21 @@ static void cpsw_rx_handler(void *token, int len, int status)
 	skb->dev = ndev;
 	if (status & CPDMA_RX_VLAN_ENCAP)
 		cpsw_rx_vlan_encap(skb);
-	if (priv->rx_ts_enabled)
-		cpts_rx_timestamp(cpsw->cpts, skb);
-	skb->protocol = eth_type_trans(skb, ndev);
 
 	/* unmap page as no netstack skb page recycling */
 	page_pool_release_page(pool, page);
-	netif_receive_skb(skb);
-
 	ndev->stats.rx_bytes += len;
 	ndev->stats.rx_packets++;
 
+	ret = 0;
+	if (priv->rx_ts_enabled)
+		ret = cpts_rx_timestamp(cpsw->cpts, skb);
+
+	if (!ret) {
+		skb->protocol = eth_type_trans(skb, ndev);
+		netif_receive_skb(skb);
+	}
+
 requeue:
 	xmeta = page_address(new_page) + CPSW_XMETA_OFFSET;
 	xmeta->ndev = ndev;
diff --git a/drivers/net/ethernet/ti/cpsw_new.c b/drivers/net/ethernet/ti/cpsw_new.c
index 9209e613257d..8561f0e3b769 100644
--- a/drivers/net/ethernet/ti/cpsw_new.c
+++ b/drivers/net/ethernet/ti/cpsw_new.c
@@ -375,17 +375,22 @@ static void cpsw_rx_handler(void *token, int len, int status)
 	skb->dev = ndev;
 	if (status & CPDMA_RX_VLAN_ENCAP)
 		cpsw_rx_vlan_encap(skb);
-	if (priv->rx_ts_enabled)
-		cpts_rx_timestamp(cpsw->cpts, skb);
-	skb->protocol = eth_type_trans(skb, ndev);
 
 	/* unmap page as no netstack skb page recycling */
 	page_pool_release_page(pool, page);
-	netif_receive_skb(skb);
 
 	ndev->stats.rx_bytes += len;
 	ndev->stats.rx_packets++;
 
+	ret = 0;
+	if (priv->rx_ts_enabled)
+		ret = cpts_rx_timestamp(cpsw->cpts, skb);
+
+	if (!ret) {
+		skb->protocol = eth_type_trans(skb, ndev);
+		netif_receive_skb(skb);
+	}
+
 requeue:
 	xmeta = page_address(new_page) + CPSW_XMETA_OFFSET;
 	xmeta->ndev = ndev;
diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 3cfa0f78287b..fe70eb677b88 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -311,6 +311,66 @@ static bool cpts_match_tx_ts(struct cpts *cpts, struct cpts_event *event)
 	return found;
 }
 
+static bool cpts_match_rx_ts(struct cpts *cpts, struct cpts_event *event)
+{
+	struct sk_buff_head rxq_list;
+	struct sk_buff_head tempq;
+	struct sk_buff *skb, *tmp;
+	unsigned long flags;
+	bool found = false;
+	u32 mtype_seqid;
+
+	mtype_seqid = event->high &
+		      ((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
+		       (SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
+		       (EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
+
+	__skb_queue_head_init(&rxq_list);
+	__skb_queue_head_init(&tempq);
+
+	spin_lock_irqsave(&cpts->rxq.lock, flags);
+	skb_queue_splice_init(&cpts->rxq, &rxq_list);
+	spin_unlock_irqrestore(&cpts->rxq.lock, flags);
+
+	skb_queue_walk_safe(&rxq_list, skb, tmp) {
+		struct skb_shared_hwtstamps *ssh;
+		struct cpts_skb_cb_data *skb_cb =
+					(struct cpts_skb_cb_data *)skb->cb;
+
+		if (mtype_seqid == skb_cb->skb_mtype_seqid) {
+			__skb_unlink(skb, &rxq_list);
+			ssh = skb_hwtstamps(skb);
+			memset(ssh, 0, sizeof(*ssh));
+			ssh->hwtstamp = ns_to_ktime(event->timestamp);
+			found = true;
+			dev_dbg(cpts->dev, "match rx timestamp mtype_seqid %08x\n",
+				mtype_seqid);
+			__skb_queue_tail(&tempq, skb);
+			break;
+		}
+
+		if (time_after(jiffies, skb_cb->tmo)) {
+			/* timeout any expired skbs */
+			dev_dbg(cpts->dev, "expiring rx timestamp\n");
+			__skb_unlink(skb, &rxq_list);
+			__skb_queue_tail(&tempq, skb);
+		}
+	}
+
+	spin_lock_irqsave(&cpts->rxq.lock, flags);
+	skb_queue_splice(&rxq_list, &cpts->rxq);
+	spin_unlock_irqrestore(&cpts->rxq.lock, flags);
+
+	local_bh_disable();
+	while ((skb = __skb_dequeue(&tempq))) {
+		skb->protocol = eth_type_trans(skb, skb->dev);
+		netif_receive_skb(skb);
+	}
+	local_bh_enable();
+
+	return found;
+}
+
 static void cpts_process_events(struct cpts *cpts)
 {
 	struct list_head *this, *next;
@@ -318,6 +378,7 @@ static void cpts_process_events(struct cpts *cpts)
 	LIST_HEAD(events_free);
 	unsigned long flags;
 	LIST_HEAD(events);
+	int type;
 
 	spin_lock_irqsave(&cpts->lock, flags);
 	list_splice_init(&cpts->events, &events);
@@ -325,8 +386,18 @@ static void cpts_process_events(struct cpts *cpts)
 
 	list_for_each_safe(this, next, &events) {
 		event = list_entry(this, struct cpts_event, list);
-		if (cpts_match_tx_ts(cpts, event) ||
-		    time_after(jiffies, event->tmo)) {
+		type = event_type(event);
+
+		if (type == CPTS_EV_TX &&
+		    (cpts_match_tx_ts(cpts, event) ||
+		     time_after(jiffies, event->tmo))) {
+			list_del_init(&event->list);
+			list_add(&event->list, &events_free);
+		}
+
+		if (type == CPTS_EV_RX &&
+		    (cpts_match_rx_ts(cpts, event) ||
+		     time_after(jiffies, event->tmo))) {
 			list_del_init(&event->list);
 			list_add(&event->list, &events_free);
 		}
@@ -422,64 +493,27 @@ static int cpts_skb_get_mtype_seqid(struct sk_buff *skb, u32 *mtype_seqid)
 	return 1;
 }
 
-static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb,
-			int ev_type, u32 skb_mtype_seqid)
-{
-	struct list_head *this, *next;
-	struct cpts_event *event;
-	unsigned long flags;
-	u32 mtype_seqid;
-	u64 ns = 0;
-
-	cpts_fifo_read(cpts, -1);
-	spin_lock_irqsave(&cpts->lock, flags);
-	list_for_each_safe(this, next, &cpts->events) {
-		event = list_entry(this, struct cpts_event, list);
-		if (event_expired(event)) {
-			list_del_init(&event->list);
-			list_add(&event->list, &cpts->pool);
-			continue;
-		}
-
-		mtype_seqid = event->high &
-			      ((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
-			       (SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
-			       (EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
-
-		if (mtype_seqid == skb_mtype_seqid) {
-			ns = event->timestamp;
-			list_del_init(&event->list);
-			list_add(&event->list, &cpts->pool);
-			break;
-		}
-	}
-	spin_unlock_irqrestore(&cpts->lock, flags);
-
-	return ns;
-}
-
-void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
+int cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
 	struct cpts_skb_cb_data *skb_cb = (struct cpts_skb_cb_data *)skb->cb;
-	struct skb_shared_hwtstamps *ssh;
 	int ret;
-	u64 ns;
 
 	ret = cpts_skb_get_mtype_seqid(skb, &skb_cb->skb_mtype_seqid);
 	if (!ret)
-		return;
+		return 0;
 
 	skb_cb->skb_mtype_seqid |= (CPTS_EV_RX << EVENT_TYPE_SHIFT);
 
 	dev_dbg(cpts->dev, "%s mtype seqid %08x\n",
 		__func__, skb_cb->skb_mtype_seqid);
 
-	ns = cpts_find_ts(cpts, skb, CPTS_EV_RX, skb_cb->skb_mtype_seqid);
-	if (!ns)
-		return;
-	ssh = skb_hwtstamps(skb);
-	memset(ssh, 0, sizeof(*ssh));
-	ssh->hwtstamp = ns_to_ktime(ns);
+	/* Always defer RX TS processing to PTP worker */
+	/* get the timestamp for timeouts */
+	skb_cb->tmo = jiffies + msecs_to_jiffies(CPTS_SKB_RX_TX_TMO);
+	skb_queue_tail(&cpts->rxq, skb);
+	ptp_schedule_worker(cpts->clock, 0);
+
+	return 1;
 }
 EXPORT_SYMBOL_GPL(cpts_rx_timestamp);
 
@@ -514,6 +548,7 @@ int cpts_register(struct cpts *cpts)
 	int err, i;
 
 	skb_queue_head_init(&cpts->txq);
+	skb_queue_head_init(&cpts->rxq);
 	INIT_LIST_HEAD(&cpts->events);
 	INIT_LIST_HEAD(&cpts->pool);
 	for (i = 0; i < CPTS_MAX_EVENTS; i++)
@@ -556,6 +591,7 @@ void cpts_unregister(struct cpts *cpts)
 
 	/* Drop all packet */
 	skb_queue_purge(&cpts->txq);
+	skb_queue_purge(&cpts->rxq);
 
 	clk_disable(cpts->refclk);
 }
diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h
index f16e14d67f5f..d6069198e059 100644
--- a/drivers/net/ethernet/ti/cpts.h
+++ b/drivers/net/ethernet/ti/cpts.h
@@ -115,12 +115,13 @@ struct cpts {
 	struct cpts_event pool_data[CPTS_MAX_EVENTS];
 	unsigned long ov_check_period;
 	struct sk_buff_head txq;
+	struct sk_buff_head rxq;
 	u64 cur_timestamp;
 	u32 mult_new;
 	struct mutex ptp_clk_mutex; /* sync PTP interface and worker */
 };
 
-void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb);
+int cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb);
 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb);
 int cpts_register(struct cpts *cpts);
 void cpts_unregister(struct cpts *cpts);
@@ -141,8 +142,9 @@ static inline bool cpts_can_timestamp(struct cpts *cpts, struct sk_buff *skb)
 #else
 struct cpts;
 
-static inline void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
+static inline int cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
+	return 0;
 }
 static inline void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
-- 
2.17.1

[PATCH net-next v3 09/11] net: ethernet: ti: cpts: add irq support

[Grygorii Strashko]

Add CPTS IRQ support, but do not enable it. By default, the CPTS driver
will continue working using polling mode which is required for CPTS to
continue working on platforms other than CPSW, like Keystone 2.

The CPTS IRQ support is required to enable support for HW_TS_PUSH events.
The CPSW CPTS IRQ and HW_TS_PUSH events support will be enabled in follow
up patches.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpts.c | 22 +++++++++++++++++++++-
 drivers/net/ethernet/ti/cpts.h | 16 ++++++++++++++++
 2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index fe70eb677b88..187fd1398b7e 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -99,6 +99,7 @@ static void cpts_purge_txq(struct cpts *cpts)
  */
 static int cpts_fifo_read(struct cpts *cpts, int match)
 {
+	bool need_schedule = false;
 	struct cpts_event *event;
 	unsigned long flags;
 	int i, type = -1;
@@ -131,6 +132,8 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 				cpts->cc.mult = cpts->mult_new;
 				cpts->mult_new = 0;
 			}
+			if (!cpts->irq_poll)
+				complete(&cpts->ts_push_complete);
 			break;
 		case CPTS_EV_TX:
 		case CPTS_EV_RX:
@@ -139,6 +142,7 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 
 			list_del_init(&event->list);
 			list_add_tail(&event->list, &cpts->events);
+			need_schedule = true;
 			break;
 		case CPTS_EV_ROLL:
 		case CPTS_EV_HALF:
@@ -154,9 +158,17 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 
 	spin_unlock_irqrestore(&cpts->lock, flags);
 
+	if (!cpts->irq_poll && need_schedule)
+		ptp_schedule_worker(cpts->clock, 0);
+
 	return type == match ? 0 : -1;
 }
 
+void cpts_misc_interrupt(struct cpts *cpts)
+{
+	cpts_fifo_read(cpts, -1);
+}
+
 static u64 cpts_systim_read(const struct cyclecounter *cc)
 {
 	struct cpts *cpts = container_of(cc, struct cpts, cc);
@@ -169,6 +181,8 @@ static void cpts_update_cur_time(struct cpts *cpts, int match,
 {
 	unsigned long flags;
 
+	reinit_completion(&cpts->ts_push_complete);
+
 	/* use spin_lock_irqsave() here as it has to run very fast */
 	spin_lock_irqsave(&cpts->lock, flags);
 	ptp_read_system_prets(sts);
@@ -177,8 +191,12 @@ static void cpts_update_cur_time(struct cpts *cpts, int match,
 	ptp_read_system_postts(sts);
 	spin_unlock_irqrestore(&cpts->lock, flags);
 
-	if (cpts_fifo_read(cpts, match) && match != -1)
+	if (cpts->irq_poll && cpts_fifo_read(cpts, match) && match != -1)
 		dev_err(cpts->dev, "cpts: unable to obtain a time stamp\n");
+
+	if (!cpts->irq_poll &&
+	    !wait_for_completion_timeout(&cpts->ts_push_complete, HZ))
+		dev_err(cpts->dev, "cpts: obtain a time stamp timeout\n");
 }
 
 /* PTP clock operations */
@@ -744,8 +762,10 @@ struct cpts *cpts_create(struct device *dev, void __iomem *regs,
 
 	cpts->dev = dev;
 	cpts->reg = (struct cpsw_cpts __iomem *)regs;
+	cpts->irq_poll = true;
 	spin_lock_init(&cpts->lock);
 	mutex_init(&cpts->ptp_clk_mutex);
+	init_completion(&cpts->ts_push_complete);
 
 	ret = cpts_of_parse(cpts, node);
 	if (ret)
diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h
index d6069198e059..e18cb5e436fe 100644
--- a/drivers/net/ethernet/ti/cpts.h
+++ b/drivers/net/ethernet/ti/cpts.h
@@ -119,6 +119,8 @@ struct cpts {
 	u64 cur_timestamp;
 	u32 mult_new;
 	struct mutex ptp_clk_mutex; /* sync PTP interface and worker */
+	bool irq_poll;
+	struct completion	ts_push_complete;
 };
 
 int cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb);
@@ -128,6 +130,7 @@ void cpts_unregister(struct cpts *cpts);
 struct cpts *cpts_create(struct device *dev, void __iomem *regs,
 			 struct device_node *node);
 void cpts_release(struct cpts *cpts);
+void cpts_misc_interrupt(struct cpts *cpts);
 
 static inline bool cpts_can_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
@@ -139,6 +142,11 @@ static inline bool cpts_can_timestamp(struct cpts *cpts, struct sk_buff *skb)
 	return true;
 }
 
+static inline void cpts_set_irqpoll(struct cpts *cpts, bool en)
+{
+	cpts->irq_poll = en;
+}
+
 #else
 struct cpts;
 
@@ -175,6 +183,14 @@ static inline bool cpts_can_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
 	return false;
 }
+
+static inline void cpts_misc_interrupt(struct cpts *cpts)
+{
+}
+
+static inline void cpts_set_irqpoll(struct cpts *cpts, bool en)
+{
+}
 #endif
 
 
-- 
2.17.1

[PATCH net-next v3 10/11] net: ethernet: ti: cpts: add support for HW_TS_PUSH events

[Grygorii Strashko]

Hence CPTS IRQ support is in place the W_TS_PUSH events can be added.
PWM capable DmTimers can be used to generete input signals for CPTS on TI
AM335x/AM437x/DRA7 SoCs to be timestamped:
AM335x/AM437x: timer4 - timer7
DRA7/AM57xx: timer13 - timer16

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpsw_priv.c   |  5 ++-
 drivers/net/ethernet/ti/cpts.c        | 52 ++++++++++++++++++++++++++-
 drivers/net/ethernet/ti/cpts.h        |  5 +--
 drivers/net/ethernet/ti/netcp_ethss.c |  3 +-
 4 files changed, 60 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpsw_priv.c b/drivers/net/ethernet/ti/cpsw_priv.c
index 97a058ca60ac..099208927400 100644
--- a/drivers/net/ethernet/ti/cpsw_priv.c
+++ b/drivers/net/ethernet/ti/cpsw_priv.c
@@ -28,6 +28,8 @@
 #include "cpsw_sl.h"
 #include "davinci_cpdma.h"
 
+#define CPTS_N_ETX_TS 4
+
 int (*cpsw_slave_index)(struct cpsw_common *cpsw, struct cpsw_priv *priv);
 
 void cpsw_intr_enable(struct cpsw_common *cpsw)
@@ -522,7 +524,8 @@ int cpsw_init_common(struct cpsw_common *cpsw, void __iomem *ss_regs,
 	if (!cpts_node)
 		cpts_node = cpsw->dev->of_node;
 
-	cpsw->cpts = cpts_create(cpsw->dev, cpts_regs, cpts_node);
+	cpsw->cpts = cpts_create(cpsw->dev, cpts_regs, cpts_node,
+				 CPTS_N_ETX_TS);
 	if (IS_ERR(cpsw->cpts)) {
 		ret = PTR_ERR(cpsw->cpts);
 		cpdma_ctlr_destroy(cpsw->dma);
diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 187fd1398b7e..403e1dbed673 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -32,6 +32,11 @@ struct cpts_skb_cb_data {
 #define cpts_read32(c, r)	readl_relaxed(&c->reg->r)
 #define cpts_write32(c, v, r)	writel_relaxed(v, &c->reg->r)
 
+static int cpts_event_port(struct cpts_event *event)
+{
+	return (event->high >> PORT_NUMBER_SHIFT) & PORT_NUMBER_MASK;
+}
+
 static int event_expired(struct cpts_event *event)
 {
 	return time_after(jiffies, event->tmo);
@@ -99,6 +104,7 @@ static void cpts_purge_txq(struct cpts *cpts)
  */
 static int cpts_fifo_read(struct cpts *cpts, int match)
 {
+	struct ptp_clock_event pevent;
 	bool need_schedule = false;
 	struct cpts_event *event;
 	unsigned long flags;
@@ -146,7 +152,12 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 			break;
 		case CPTS_EV_ROLL:
 		case CPTS_EV_HALF:
+			break;
 		case CPTS_EV_HW:
+			pevent.timestamp = event->timestamp;
+			pevent.type = PTP_CLOCK_EXTTS;
+			pevent.index = cpts_event_port(event) - 1;
+			ptp_clock_event(cpts->clock, &pevent);
 			break;
 		default:
 			dev_err(cpts->dev, "cpts: unknown event type\n");
@@ -272,9 +283,45 @@ static int cpts_ptp_settime(struct ptp_clock_info *ptp,
 	return 0;
 }
 
+static int cpts_extts_enable(struct cpts *cpts, u32 index, int on)
+{
+	u32 v;
+
+	if (index >= cpts->info.n_ext_ts)
+		return -ENXIO;
+
+	if (((cpts->hw_ts_enable & BIT(index)) >> index) == on)
+		return 0;
+
+	mutex_lock(&cpts->ptp_clk_mutex);
+
+	v = cpts_read32(cpts, control);
+	if (on) {
+		v |= BIT(8 + index);
+		cpts->hw_ts_enable |= BIT(index);
+	} else {
+		v &= ~BIT(8 + index);
+		cpts->hw_ts_enable &= ~BIT(index);
+	}
+	cpts_write32(cpts, v, control);
+
+	mutex_unlock(&cpts->ptp_clk_mutex);
+
+	return 0;
+}
+
 static int cpts_ptp_enable(struct ptp_clock_info *ptp,
 			   struct ptp_clock_request *rq, int on)
 {
+	struct cpts *cpts = container_of(ptp, struct cpts, info);
+
+	switch (rq->type) {
+	case PTP_CLK_REQ_EXTTS:
+		return cpts_extts_enable(cpts, rq->extts.index, on);
+	default:
+		break;
+	}
+
 	return -EOPNOTSUPP;
 }
 
@@ -751,7 +798,7 @@ static int cpts_of_parse(struct cpts *cpts, struct device_node *node)
 }
 
 struct cpts *cpts_create(struct device *dev, void __iomem *regs,
-			 struct device_node *node)
+			 struct device_node *node, u32 n_ext_ts)
 {
 	struct cpts *cpts;
 	int ret;
@@ -790,6 +837,9 @@ struct cpts *cpts_create(struct device *dev, void __iomem *regs,
 	cpts->cc.mask = CLOCKSOURCE_MASK(32);
 	cpts->info = cpts_info;
 
+	if (n_ext_ts)
+		cpts->info.n_ext_ts = n_ext_ts;
+
 	cpts_calc_mult_shift(cpts);
 	/* save cc.mult original value as it can be modified
 	 * by cpts_ptp_adjfreq().
diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h
index e18cb5e436fe..acffe8a29b32 100644
--- a/drivers/net/ethernet/ti/cpts.h
+++ b/drivers/net/ethernet/ti/cpts.h
@@ -121,6 +121,7 @@ struct cpts {
 	struct mutex ptp_clk_mutex; /* sync PTP interface and worker */
 	bool irq_poll;
 	struct completion	ts_push_complete;
+	u32 hw_ts_enable;
 };
 
 int cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb);
@@ -128,7 +129,7 @@ void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb);
 int cpts_register(struct cpts *cpts);
 void cpts_unregister(struct cpts *cpts);
 struct cpts *cpts_create(struct device *dev, void __iomem *regs,
-			 struct device_node *node);
+			 struct device_node *node, u32 n_ext_ts);
 void cpts_release(struct cpts *cpts);
 void cpts_misc_interrupt(struct cpts *cpts);
 
@@ -160,7 +161,7 @@ static inline void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 
 static inline
 struct cpts *cpts_create(struct device *dev, void __iomem *regs,
-			 struct device_node *node)
+			 struct device_node *node, u32 n_ext_ts)
 {
 	return NULL;
 }
diff --git a/drivers/net/ethernet/ti/netcp_ethss.c b/drivers/net/ethernet/ti/netcp_ethss.c
index fb36115e9c51..9d6e27fb710e 100644
--- a/drivers/net/ethernet/ti/netcp_ethss.c
+++ b/drivers/net/ethernet/ti/netcp_ethss.c
@@ -3716,7 +3716,8 @@ static int gbe_probe(struct netcp_device *netcp_device, struct device *dev,
 	if (!cpts_node)
 		cpts_node = of_node_get(node);
 
-	gbe_dev->cpts = cpts_create(gbe_dev->dev, gbe_dev->cpts_reg, cpts_node);
+	gbe_dev->cpts = cpts_create(gbe_dev->dev, gbe_dev->cpts_reg,
+				    cpts_node, 0);
 	of_node_put(cpts_node);
 	if (IS_ENABLED(CONFIG_TI_CPTS) && IS_ERR(gbe_dev->cpts)) {
 		ret = PTR_ERR(gbe_dev->cpts);
-- 
2.17.1

[PATCH net-next v3 11/11] net: ethernet: ti: cpsw: enable cpts irq

[Grygorii Strashko]

The CPSW misc IRQ need be enabled for CPTS event_pend IRQs processing. This
patch adds corresponding support to CPSW driver.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpsw.c      | 21 +++++++++++++++++++++
 drivers/net/ethernet/ti/cpsw_new.c  | 20 ++++++++++++++++++++
 drivers/net/ethernet/ti/cpsw_priv.c | 12 ++++++++++++
 drivers/net/ethernet/ti/cpsw_priv.h |  2 ++
 4 files changed, 55 insertions(+)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index ce2155394830..ce8151e95443 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -1573,6 +1573,12 @@ static int cpsw_probe(struct platform_device *pdev)
 		return irq;
 	cpsw->irqs_table[1] = irq;
 
+	/* get misc irq*/
+	irq = platform_get_irq(pdev, 3);
+	if (irq <= 0)
+		return irq;
+	cpsw->misc_irq = irq;
+
 	/*
 	 * This may be required here for child devices.
 	 */
@@ -1707,6 +1713,21 @@ static int cpsw_probe(struct platform_device *pdev)
 		goto clean_unregister_netdev_ret;
 	}
 
+	if (!cpsw->cpts)
+		goto skip_cpts;
+
+	ret = devm_request_irq(&pdev->dev, cpsw->misc_irq, cpsw_misc_interrupt,
+			       0, dev_name(&pdev->dev), cpsw);
+	if (ret < 0) {
+		dev_err(dev, "error attaching misc irq (%d)\n", ret);
+		goto clean_unregister_netdev_ret;
+	}
+
+	/* Enable misc CPTS evnt_pend IRQ */
+	cpts_set_irqpoll(cpsw->cpts, false);
+	writel(0x10, &cpsw->wr_regs->misc_en);
+
+skip_cpts:
 	cpsw_notice(priv, probe,
 		    "initialized device (regs %pa, irq %d, pool size %d)\n",
 		    &ss_res->start, cpsw->irqs_table[0], descs_pool_size);
diff --git a/drivers/net/ethernet/ti/cpsw_new.c b/drivers/net/ethernet/ti/cpsw_new.c
index 8561f0e3b769..5d7c8ea4b5c7 100644
--- a/drivers/net/ethernet/ti/cpsw_new.c
+++ b/drivers/net/ethernet/ti/cpsw_new.c
@@ -1901,6 +1901,11 @@ static int cpsw_probe(struct platform_device *pdev)
 		return irq;
 	cpsw->irqs_table[1] = irq;
 
+	irq = platform_get_irq_byname(pdev, "misc");
+	if (irq <= 0)
+		return irq;
+	cpsw->misc_irq = irq;
+
 	platform_set_drvdata(pdev, cpsw);
 	/* This may be required here for child devices. */
 	pm_runtime_enable(dev);
@@ -1980,6 +1985,21 @@ static int cpsw_probe(struct platform_device *pdev)
 		goto clean_unregister_netdev;
 	}
 
+	if (!cpsw->cpts)
+		goto skip_cpts;
+
+	ret = devm_request_irq(dev, cpsw->misc_irq, cpsw_misc_interrupt,
+			       0, dev_name(&pdev->dev), cpsw);
+	if (ret < 0) {
+		dev_err(dev, "error attaching misc irq (%d)\n", ret);
+		goto clean_unregister_netdev;
+	}
+
+	/* Enable misc CPTS evnt_pend IRQ */
+	cpts_set_irqpoll(cpsw->cpts, false);
+	writel(0x10, &cpsw->wr_regs->misc_en);
+
+skip_cpts:
 	ret = cpsw_register_notifiers(cpsw);
 	if (ret)
 		goto clean_unregister_netdev;
diff --git a/drivers/net/ethernet/ti/cpsw_priv.c b/drivers/net/ethernet/ti/cpsw_priv.c
index 099208927400..9d098c802c6d 100644
--- a/drivers/net/ethernet/ti/cpsw_priv.c
+++ b/drivers/net/ethernet/ti/cpsw_priv.c
@@ -114,6 +114,18 @@ irqreturn_t cpsw_rx_interrupt(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+irqreturn_t cpsw_misc_interrupt(int irq, void *dev_id)
+{
+	struct cpsw_common *cpsw = dev_id;
+
+	writel(0, &cpsw->wr_regs->misc_en);
+	cpdma_ctlr_eoi(cpsw->dma, CPDMA_EOI_MISC);
+	cpts_misc_interrupt(cpsw->cpts);
+	writel(0x10, &cpsw->wr_regs->misc_en);
+
+	return IRQ_HANDLED;
+}
+
 int cpsw_tx_mq_poll(struct napi_struct *napi_tx, int budget)
 {
 	struct cpsw_common	*cpsw = napi_to_cpsw(napi_tx);
diff --git a/drivers/net/ethernet/ti/cpsw_priv.h b/drivers/net/ethernet/ti/cpsw_priv.h
index b8d7b924ee3d..bf4e179b4ca4 100644
--- a/drivers/net/ethernet/ti/cpsw_priv.h
+++ b/drivers/net/ethernet/ti/cpsw_priv.h
@@ -350,6 +350,7 @@ struct cpsw_common {
 	bool				rx_irq_disabled;
 	bool				tx_irq_disabled;
 	u32 irqs_table[IRQ_NUM];
+	int misc_irq;
 	struct cpts			*cpts;
 	struct devlink *devlink;
 	int				rx_ch_num, tx_ch_num;
@@ -442,6 +443,7 @@ int cpsw_run_xdp(struct cpsw_priv *priv, int ch, struct xdp_buff *xdp,
 		 struct page *page, int port);
 irqreturn_t cpsw_tx_interrupt(int irq, void *dev_id);
 irqreturn_t cpsw_rx_interrupt(int irq, void *dev_id);
+irqreturn_t cpsw_misc_interrupt(int irq, void *dev_id);
 int cpsw_tx_mq_poll(struct napi_struct *napi_tx, int budget);
 int cpsw_tx_poll(struct napi_struct *napi_tx, int budget);
 int cpsw_rx_mq_poll(struct napi_struct *napi_rx, int budget);
-- 
2.17.1

Re: [PATCH net-next v3 00/11] net: ethernet: ti: cpts: add irq and HW_TS_PUSH events

[David Miller]

From: Grygorii Strashko <grygorii.strashko@ti.com>
Date: Fri, 20 Mar 2020 21:42:33 +0200

> Dependency:
>  ff7cf1822b93 kthread: mark timer used by delayed kthread works as IRQ safe
>  which was merged in -next, but has to be back-ported for testing with earlier
>  versions

I don't see this commit in my net-next tree so I cannot merge this.

Re: [PATCH net-next v3 00/11] net: ethernet: ti: cpts: add irq and HW_TS_PUSH events

[Richard Cochran]

On Fri, Mar 20, 2020 at 09:42:33PM +0200, Grygorii Strashko wrote:
> Main changes comparing to initial submission:
> - both RX/TX timestamp processing deferred to ptp worker

I can't see any benefit in delaying Rx time stamps.
What is the reason for this change?

Thanks,
Richard

Re: [PATCH net-next v3 08/11] net: ethernet: ti: cpts: move rx timestamp processing to ptp worker only

[Richard Cochran]

On Fri, Mar 20, 2020 at 09:42:41PM +0200, Grygorii Strashko wrote:
> Once CPTS IRQ will be enabled the CPTS irq handler may compete with netif
> RX sofirq path and so RX timestamp might not be ready at the moment packet
> is processed. As result, packet has to be deferred and processed later.

This change is not necessary.  The Rx path can simply take a spinlock,
check the event list and the HW queue.
 
> This patch moves RX timestamp processing tx timestamp processing to PTP
> worker always the same way as it's been done for TX timestamps.

There is no advantage to delaying Rx time stamp delivery.  In fact, it
can degrade synchronization performance.  The only reason the
implementation delays Tx time stamps delivery is because there is no
other way.

Thanks,
Richard

Re: [PATCH net-next v3 08/11] net: ethernet: ti: cpts: move rx timestamp processing to ptp worker only

[Grygorii Strashko]

On 24/03/2020 15:43, Richard Cochran wrote:
> On Fri, Mar 20, 2020 at 09:42:41PM +0200, Grygorii Strashko wrote:
>> Once CPTS IRQ will be enabled the CPTS irq handler may compete with netif
>> RX sofirq path and so RX timestamp might not be ready at the moment packet
>> is processed. As result, packet has to be deferred and processed later.
> 
> This change is not necessary.  The Rx path can simply take a spinlock,
> check the event list and the HW queue.
>   
>> This patch moves RX timestamp processing tx timestamp processing to PTP
>> worker always the same way as it's been done for TX timestamps.
> 
> There is no advantage to delaying Rx time stamp delivery.  In fact, it
> can degrade synchronization performance.  The only reason the
> implementation delays Tx time stamps delivery is because there is no
> other way.

I tested both ways and kept this version as i'v not seen any degradation,
but, of course, i'll redo the test (or may be you can advise what test to run).

My thoughts were - network stack might not immediately deliver packet to the application
and PTP worker can be tuned (pri and smp_affinity), resulted code will be more structured,
less locks and less time spent in softirq context.

I also can drop it.

-- 
Best regards,
grygorii

Re: [PATCH net-next v3 08/11] net: ethernet: ti: cpts: move rx timestamp processing to ptp worker only

[Richard Cochran]

On Tue, Mar 24, 2020 at 05:34:34PM +0200, Grygorii Strashko wrote:
> I tested both ways and kept this version as i'v not seen any degradation,
> but, of course, i'll redo the test (or may be you can advise what test to run).

Measure the time delay from when the frame arrives in the stack until
that frame+RxTimestamp arrives in the application.  I expect the round
about way via kthread takes longer. 
 
> My thoughts were - network stack might not immediately deliver packet to the application

The network stack always delivers the packet, but you artificially
delay that delivery by calling netif_receive_skb() later on from
cpts_match_rx_ts().

> and PTP worker can be tuned (pri and smp_affinity),

That won't avoid the net softirq.

> resulted code will be more structured,

I am afraid people will copy this pattern in new drivers.  It really
does not make much sense.

Thanks,
Richard

Re: [PATCH net-next v3 08/11] net: ethernet: ti: cpts: move rx timestamp processing to ptp worker only

[Grygorii Strashko]

Hi Richard

On 24/03/2020 18:54, Richard Cochran wrote:
> On Tue, Mar 24, 2020 at 05:34:34PM +0200, Grygorii Strashko wrote:
>> I tested both ways and kept this version as i'v not seen any degradation,
>> but, of course, i'll redo the test (or may be you can advise what test to run).
> 
> Measure the time delay from when the frame arrives in the stack until
> that frame+RxTimestamp arrives in the application.  I expect the round
> about way via kthread takes longer.
>   
>> My thoughts were - network stack might not immediately deliver packet to the application
> 
> The network stack always delivers the packet, but you artificially
> delay that delivery by calling netif_receive_skb() later on from
> cpts_match_rx_ts().
> 
>> and PTP worker can be tuned (pri and smp_affinity),
> 
> That won't avoid the net softirq.
> 
>> resulted code will be more structured,
> 
> I am afraid people will copy this pattern in new drivers.  It really
> does not make much sense.

I did additional testing and will drop this patch.
Any other comments from you side?

Thank you.

-- 
Best regards,
grygorii

Re: [PATCH net-next v3 01/11] net: ethernet: ti: cpts: use dev_yy() api for logs

[Richard Cochran]

On Fri, Mar 20, 2020 at 09:42:34PM +0200, Grygorii Strashko wrote:
> @@ -150,7 +150,7 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
>  			break;
>  
>  		if (list_empty(&cpts->pool) && cpts_purge_events(cpts)) {
> -			pr_err("cpts: event pool empty\n");
> +			dev_info(cpts->dev, "cpts: event pool empty\n");

You changed err into info.  Was that on purpose?

The size of the pool is hard coded, but it should be large enough for
any use case.  If the pool size turns out to be too small at run time,
then I think the message deserves at least the level of warning.

Thanks,
Richard

Re: [PATCH net-next v3 02/11] net: ethernet: ti: cpts: separate hw counter read from timecounter

[Richard Cochran]

On Fri, Mar 20, 2020 at 09:42:35PM +0200, Grygorii Strashko wrote:
> Separate hw counter read from timecounter code:
> - add CPTS context field to store current HW counter value
> - move HW timestamp request and FIFO read code out of timecounter code
> - convert cyc2time on event reception in cpts_fifo_read()
> - call timecounter_read() in cpts_fifo_read() to update tk->cycle_last

This comment tells us WHAT the patch does, but does not help because
we can see that from the patch itself.  Instead, the comment should
tell us WHY is change is needed.

I was left scratching my head, with the question, what is the purpose
here?  Maybe the answer is to be found later on in the series.

Here is commit message pattern to follow that I learned from tglx:

1. context
2. problem
3. solution

For this patch, the sentence, "Separate hw counter read from
timecounter code" is #3.

Thanks,
Richard

Re: [PATCH net-next v3 03/11] net: ethernet: ti: cpts: move tc mult update in cpts_fifo_read()

[Richard Cochran]

On Fri, Mar 20, 2020 at 09:42:36PM +0200, Grygorii Strashko wrote:
> Now CPTS driver .adjfreq() generates request to read CPTS current time
> (CPTS_EV_PUSH) with intention to process all pending event using previous
> frequency adjustment values before switching to the new ones. So
> CPTS_EV_PUSH works as a marker to switch to the new frequency adjustment
> values. Current code assumes that all job is done in .adjfreq(), but after
> enabling IRQ this will not be true any more.
> 
> Hence save new frequency adjustment values (mult) and perform actual freq
> adjustment in cpts_fifo_read() immediately after CPTS_EV_PUSH is received.

Now THIS comment is much better!  The explanation here really should
be in the previous patch, to help poor reviewers like me.

Thanks,
Richard
 

Re: [PATCH net-next v3 06/11] net: ethernet: ti: cpts: move tx timestamp processing to ptp worker only

[Richard Cochran]

On Fri, Mar 20, 2020 at 09:42:39PM +0200, Grygorii Strashko wrote:
> Now the tx timestamp processing happens from different contexts - softirq
> and thread/PTP worker. Enabling IRQ will add one more hard_irq context.
> This makes over all defered TX timestamp processing and locking
> overcomplicated. Move tx timestamp processing to PTP worker always instead.
> 
> napi_rx->cpts_tx_timestamp
>  if ptp_packet then
>     push to txq
>     ptp_schedule_worker()
> 
> do_aux_work->cpts_overflow_check
>  cpts_process_events()

Since cpts_overflow_check() is performing new functions, consider
renaming it to match.

Thanks,
Richard

Re: [PATCH net-next v3 02/11] net: ethernet: ti: cpts: separate hw counter read from timecounter

[Grygorii Strashko]

On 26/03/2020 16:18, Richard Cochran wrote:
> On Fri, Mar 20, 2020 at 09:42:35PM +0200, Grygorii Strashko wrote:
>> Separate hw counter read from timecounter code:
>> - add CPTS context field to store current HW counter value
>> - move HW timestamp request and FIFO read code out of timecounter code
>> - convert cyc2time on event reception in cpts_fifo_read()
>> - call timecounter_read() in cpts_fifo_read() to update tk->cycle_last
> 
> This comment tells us WHAT the patch does, but does not help because
> we can see that from the patch itself.  Instead, the comment should
> tell us WHY is change is needed.
> 
> I was left scratching my head, with the question, what is the purpose
> here?  Maybe the answer is to be found later on in the series.
> 
> Here is commit message pattern to follow that I learned from tglx:
> 
> 1. context
> 2. problem
> 3. solution
> 
> For this patch, the sentence, "Separate hw counter read from
> timecounter code" is #3.

Sorry, will update.

-- 
Best regards,
grygorii

Re: [PATCH net-next v3 06/11] net: ethernet: ti: cpts: move tx timestamp processing to ptp worker only

[Grygorii Strashko]

On 26/03/2020 16:29, Richard Cochran wrote:
> On Fri, Mar 20, 2020 at 09:42:39PM +0200, Grygorii Strashko wrote:
>> Now the tx timestamp processing happens from different contexts - softirq
>> and thread/PTP worker. Enabling IRQ will add one more hard_irq context.
>> This makes over all defered TX timestamp processing and locking
>> overcomplicated. Move tx timestamp processing to PTP worker always instead.
>>
>> napi_rx->cpts_tx_timestamp
>>   if ptp_packet then
>>      push to txq
>>      ptp_schedule_worker()
>>
>> do_aux_work->cpts_overflow_check
>>   cpts_process_events()
> 
> Since cpts_overflow_check() is performing new functions, consider
> renaming it to match.

It's still performs overflow check

static long cpts_overflow_check(struct ptp_clock_info *ptp)
{
...

	mutex_lock(&cpts->ptp_clk_mutex);

	cpts_update_cur_time(cpts, -1, NULL);
^^^ here
	ns = timecounter_read(&cpts->tc);


	cpts_process_events(cpts);

What name would you suggest?

Thank you.

-- 
Best regards,
grygorii

Re: [PATCH net-next v3 03/11] net: ethernet: ti: cpts: move tc mult update in cpts_fifo_read()

[Grygorii Strashko]

On 26/03/2020 16:20, Richard Cochran wrote:
> On Fri, Mar 20, 2020 at 09:42:36PM +0200, Grygorii Strashko wrote:
>> Now CPTS driver .adjfreq() generates request to read CPTS current time
>> (CPTS_EV_PUSH) with intention to process all pending event using previous
>> frequency adjustment values before switching to the new ones. So
>> CPTS_EV_PUSH works as a marker to switch to the new frequency adjustment
>> values. Current code assumes that all job is done in .adjfreq(), but after
>> enabling IRQ this will not be true any more.
>>
>> Hence save new frequency adjustment values (mult) and perform actual freq
>> adjustment in cpts_fifo_read() immediately after CPTS_EV_PUSH is received.
> 
> Now THIS comment is much better!  The explanation here really should
> be in the previous patch, to help poor reviewers like me.

I've been thinking to squash them. What's your opinion.

Thank you.

-- 
Best regards,
grygorii

Re: [PATCH net-next v3 03/11] net: ethernet: ti: cpts: move tc mult update in cpts_fifo_read()

[Richard Cochran]

On Thu, Mar 26, 2020 at 10:18:18PM +0200, Grygorii Strashko wrote:
> I've been thinking to squash them. What's your opinion.

I favor small, incremental patches.  Just the motivation for the first
patch was missing, that's all.

Thanks,
Richard

Re: [PATCH net-next v3 07/11] net: ethernet: ti: cpts: rework locking

[Richard Cochran]

On Fri, Mar 20, 2020 at 09:42:40PM +0200, Grygorii Strashko wrote:
> Now spinlock is used to synchronize everything which is not required. Add
> mutex and use to sync access to PTP interface and PTP worker and use
> spinlock only to sync FIFO/events processing.

If you haven't already, I suggest testing this change with lockdep
enabled.

Thanks,
Richard

Re: [PATCH net-next v3 10/11] net: ethernet: ti: cpts: add support for HW_TS_PUSH events

[Richard Cochran]

> +static int cpts_extts_enable(struct cpts *cpts, u32 index, int on)
> +{
> +	u32 v;
> +
> +	if (index >= cpts->info.n_ext_ts)
> +		return -ENXIO;

This check is already performed in ptp_chardev.c.

Thanks,
Richard

Re: [PATCH net-next v3 08/11] net: ethernet: ti: cpts: move rx timestamp processing to ptp worker only

[Richard Cochran]

On Thu, Mar 26, 2020 at 01:15:45PM +0200, Grygorii Strashko wrote:
> I did additional testing and will drop this patch.
> Any other comments from you side?

I made a few minor comments.  Overall the series looks good.
For the series:

Acked-by: Richard Cochran <richardcochran@gmail.com>