Commit b2bc8148 authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'ptp-virtual-clocks-and-timestamping' 



Yangbo Lu says:

====================
ptp: support virtual clocks and timestamping

Current PTP driver exposes one PTP device to user which binds network
interface/interfaces to provide timestamping. Actually we have a way
utilizing timecounter/cyclecounter to virtualize any number of PTP
clocks based on a same free running physical clock for using.
The purpose of having multiple PTP virtual clocks is for user space
to directly/easily use them for multiple domains synchronization.

user
space:     ^                                  ^
           | SO_TIMESTAMPING new flag:        | Packets with
           | SOF_TIMESTAMPING_BIND_PHC        | TX/RX HW timestamps
           v                                  v
         +--------------------------------------------+
sock:    |     sock (new member sk_bind_phc)          |
         +--------------------------------------------+
           ^                                  ^
           | ethtool_get_phc_vclocks          | Convert HW timestamps
           |                                  | to sk_bind_phc
           v                                  v
         +--------------+--------------+--------------+
vclock:  | ptp1         | ptp2         | ptpN         |
         +--------------+--------------+--------------+
pclock:  |             ptp0 free running              |
         +--------------------------------------------+

The block diagram may explain how it works. Besides the PTP virtual
clocks, the packet HW timestamp converting to the bound PHC is also
done in sock driver. For user space, PTP virtual clocks can be
created via sysfs, and extended SO_TIMESTAMPING API (new flag
SOF_TIMESTAMPING_BIND_PHC) can be used to bind one PTP virtual clock
for timestamping.

The test tool timestamping.c (together with linuxptp phc_ctl tool) can
be used to verify:

  # echo 4 > /sys/class/ptp/ptp0/n_vclocks
  [  129.399472] ptp ptp0: new virtual clock ptp2
  [  129.404234] ptp ptp0: new virtual clock ptp3
  [  129.409532] ptp ptp0: new virtual clock ptp4
  [  129.413942] ptp ptp0: new virtual clock ptp5
  [  129.418257] ptp ptp0: guarantee physical clock free running
  #
  # phc_ctl /dev/ptp2 set 10000
  # phc_ctl /dev/ptp3 set 20000
  #
  # timestamping eno0 2 SOF_TIMESTAMPING_TX_HARDWARE SOF_TIMESTAMPING_RAW_HARDWARE SOF_TIMESTAMPING_BIND_PHC
  # timestamping eno0 2 SOF_TIMESTAMPING_RX_HARDWARE SOF_TIMESTAMPING_RAW_HARDWARE SOF_TIMESTAMPING_BIND_PHC
  # timestamping eno0 3 SOF_TIMESTAMPING_TX_HARDWARE SOF_TIMESTAMPING_RAW_HARDWARE SOF_TIMESTAMPING_BIND_PHC
  # timestamping eno0 3 SOF_TIMESTAMPING_RX_HARDWARE SOF_TIMESTAMPING_RAW_HARDWARE SOF_TIMESTAMPING_BIND_PHC

Changes for v2:
	- Converted to num_vclocks for creating virtual clocks.
	- Guranteed physical clock free running when using virtual
	  clocks.
	- Fixed build warning.
	- Updated copyright.
Changes for v3:
	- Supported PTP virtual clock in default in PTP driver.
	- Protected concurrency of ptp->num_vclocks accessing.
	- Supported PHC vclocks query via ethtool.
	- Extended SO_TIMESTAMPING API for PHC binding.
	- Converted HW timestamps to PHC bound, instead of previous
	  binding domain value to PHC idea.
	- Other minor fixes.
Changes for v4:
	- Used do_aux_work callback for vclock refreshing instead.
	- Used unsigned int for vclocks number, and max_vclocks
	  for limitiation.
	- Fixed mutex locking.
	- Dynamically allocated memory for vclock index storage.
	- Removed ethtool ioctl command for vclocks getting.
	- Updated doc for ethtool phc vclocks get.
	- Converted to mptcp_setsockopt_sol_socket_timestamping().
	- Passed so_timestamping for sock_set_timestamping.
	- Fixed checkpatch/build.
	- Other minor fixed.
Changes for v5:
	- Fixed checkpatch/build/bug reported by test robot.
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 88827353 5ce15f27

Documentation/ABI/testing/sysfs-ptp

+20 −0
Original line number Diff line number Diff line
@@ -33,6 +33,13 @@ Description: 
		frequency adjustment value (a positive integer) in

		parts per billion.



What:		/sys/class/ptp/ptpN/max_vclocks

Date:		May 2021

Contact:	Yangbo Lu <yangbo.lu@nxp.com>

Description:

		This file contains the maximum number of ptp vclocks.

		Write integer to re-configure it.



What:		/sys/class/ptp/ptpN/n_alarms

Date:		September 2010

Contact:	Richard Cochran <richardcochran@gmail.com>
@@ -61,6 +68,19 @@ Description: 
		This file contains the number of programmable pins

		offered by the PTP hardware clock.



What:		/sys/class/ptp/ptpN/n_vclocks

Date:		May 2021

Contact:	Yangbo Lu <yangbo.lu@nxp.com>

Description:

		This file contains the number of virtual PTP clocks in

		use.  By default, the value is 0 meaning that only the

		physical clock is in use.  Setting the value creates

		the corresponding number of virtual clocks and causes

		the physical clock to become free running.  Setting the

		value back to 0 deletes the virtual clocks and

		switches the physical clock back to normal, adjustable

		operation.



What:		/sys/class/ptp/ptpN/pins

Date:		March 2014

Contact:	Richard Cochran <richardcochran@gmail.com>

Documentation/networking/ethtool-netlink.rst

+22 −0
Original line number Diff line number Diff line
@@ -212,6 +212,7 @@ Userspace to kernel: 
  ``ETHTOOL_MSG_FEC_SET``               set FEC settings

  ``ETHTOOL_MSG_MODULE_EEPROM_GET``     read SFP module EEPROM

  ``ETHTOOL_MSG_STATS_GET``             get standard statistics

  ``ETHTOOL_MSG_PHC_VCLOCKS_GET``       get PHC virtual clocks info

  ===================================== ================================



Kernel to userspace:
@@ -250,6 +251,7 @@ Kernel to userspace: 
  ``ETHTOOL_MSG_FEC_NTF``                  FEC settings

  ``ETHTOOL_MSG_MODULE_EEPROM_GET_REPLY``  read SFP module EEPROM

  ``ETHTOOL_MSG_STATS_GET_REPLY``          standard statistics

  ``ETHTOOL_MSG_PHC_VCLOCKS_GET_REPLY``    PHC virtual clocks info

  ======================================== =================================



``GET`` requests are sent by userspace applications to retrieve device
@@ -1477,6 +1479,25 @@ Low and high bounds are inclusive, for example: 
 etherStatsPkts512to1023Octets 512  1023

 ============================= ==== ====



PHC_VCLOCKS_GET

===============



Query device PHC virtual clocks information.



Request contents:



  ====================================  ======  ==========================

  ``ETHTOOL_A_PHC_VCLOCKS_HEADER``      nested  request header

  ====================================  ======  ==========================



Kernel response contents:



  ====================================  ======  ==========================

  ``ETHTOOL_A_PHC_VCLOCKS_HEADER``      nested  reply header

  ``ETHTOOL_A_PHC_VCLOCKS_NUM``         u32     PHC virtual clocks number

  ``ETHTOOL_A_PHC_VCLOCKS_INDEX``       s32     PHC index array

  ====================================  ======  ==========================



Request translation

===================
@@ -1575,4 +1596,5 @@ are netlink only. 
  n/a                                 ``ETHTOOL_MSG_CABLE_TEST_ACT``

  n/a                                 ``ETHTOOL_MSG_CABLE_TEST_TDR_ACT``

  n/a                                 ``ETHTOOL_MSG_TUNNEL_INFO_GET``

  n/a                                 ``ETHTOOL_MSG_PHC_VCLOCKS_GET``

  =================================== =====================================

MAINTAINERS

+7 −0
Original line number Diff line number Diff line
@@ -14890,6 +14890,13 @@ F: drivers/net/phy/dp83640* 
F:	drivers/ptp/*

F:	include/linux/ptp_cl*









PTP VIRTUAL CLOCK SUPPORT









M:	Yangbo Lu <yangbo.lu@nxp.com>









L:	netdev@vger.kernel.org









S:	Maintained









F:	drivers/ptp/ptp_vclock.c









F:	net/ethtool/phc_vclocks.c

















PTRACE SUPPORT









M:	Oleg Nesterov <oleg@redhat.com>









S:	Maintained
































drivers/ptp/Makefile



+1
−1






























Original line number
Diff line number
Diff line







@@ -3,7 +3,7 @@







# Makefile for PTP 1588 clock support.









#



















ptp-y					:= ptp_clock.o ptp_chardev.o ptp_sysfs.o









ptp-y					:= ptp_clock.o ptp_chardev.o ptp_sysfs.o ptp_vclock.o









ptp_kvm-$(CONFIG_X86)			:= ptp_kvm_x86.o ptp_kvm_common.o









ptp_kvm-$(CONFIG_HAVE_ARM_SMCCC)	:= ptp_kvm_arm.o ptp_kvm_common.o









obj-$(CONFIG_PTP_1588_CLOCK)		+= ptp.o
































drivers/ptp/ptp_clock.c



+41
−1






























Original line number
Diff line number
Diff line







@@ -24,10 +24,11 @@







#define PTP_PPS_EVENT PPS_CAPTUREASSERT









#define PTP_PPS_MODE (PTP_PPS_DEFAULTS | PPS_CANWAIT | PPS_TSFMT_TSPEC)



















struct class *ptp_class;



















/* private globals */



















static dev_t ptp_devt;









static struct class *ptp_class;



















static DEFINE_IDA(ptp_clocks_map);


















@@ -76,6 +77,11 @@ static int ptp_clock_settime(struct posix_clock *pc, const struct timespec64 *tp







{









	struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);



















	if (ptp_vclock_in_use(ptp)) {









		pr_err("ptp: virtual clock in use\n");









		return -EBUSY;









	}



















	return  ptp->info->settime64(ptp->info, tp);









}


















@@ -97,6 +103,11 @@ static int ptp_clock_adjtime(struct posix_clock *pc, struct __kernel_timex *tx)







	struct ptp_clock_info *ops;









	int err = -EOPNOTSUPP;



















	if (ptp_vclock_in_use(ptp)) {









		pr_err("ptp: virtual clock in use\n");









		return -EBUSY;









	}



















	ops = ptp->info;



















	if (tx->modes & ADJ_SETOFFSET) {








@@ -161,6 +172,7 @@ static void ptp_clock_release(struct device *dev)







	ptp_cleanup_pin_groups(ptp);









	mutex_destroy(&ptp->tsevq_mux);









	mutex_destroy(&ptp->pincfg_mux);









	mutex_destroy(&ptp->n_vclocks_mux);









	ida_simple_remove(&ptp_clocks_map, ptp->index);









	kfree(ptp);









}








@@ -185,6 +197,7 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,







{









	struct ptp_clock *ptp;









	int err = 0, index, major = MAJOR(ptp_devt);









	size_t size;



















	if (info->n_alarm > PTP_MAX_ALARMS)









		return ERR_PTR(-EINVAL);








@@ -208,6 +221,7 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,







	spin_lock_init(&ptp->tsevq.lock);









	mutex_init(&ptp->tsevq_mux);









	mutex_init(&ptp->pincfg_mux);









	mutex_init(&ptp->n_vclocks_mux);









	init_waitqueue_head(&ptp->tsev_wq);



















	if (ptp->info->do_aux_work) {








@@ -221,6 +235,22 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,







		ptp->pps_source->lookup_cookie = ptp;









	}



















	/* PTP virtual clock is being registered under physical clock */









	if (parent->class && parent->class->name &&









	    strcmp(parent->class->name, "ptp") == 0)









		ptp->is_virtual_clock = true;



















	if (!ptp->is_virtual_clock) {









		ptp->max_vclocks = PTP_DEFAULT_MAX_VCLOCKS;



















		size = sizeof(int) * ptp->max_vclocks;









		ptp->vclock_index = kzalloc(size, GFP_KERNEL);









		if (!ptp->vclock_index) {









			err = -ENOMEM;









			goto no_mem_for_vclocks;









		}









	}



















	err = ptp_populate_pin_groups(ptp);









	if (err)









		goto no_pin_groups;








@@ -265,11 +295,14 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,







no_pps:









	ptp_cleanup_pin_groups(ptp);









no_pin_groups:









	kfree(ptp->vclock_index);









no_mem_for_vclocks:









	if (ptp->kworker)









		kthread_destroy_worker(ptp->kworker);









kworker_err:









	mutex_destroy(&ptp->tsevq_mux);









	mutex_destroy(&ptp->pincfg_mux);









	mutex_destroy(&ptp->n_vclocks_mux);









	ida_simple_remove(&ptp_clocks_map, index);









no_slot:









	kfree(ptp);








@@ -280,9 +313,16 @@ EXPORT_SYMBOL(ptp_clock_register);

















int ptp_clock_unregister(struct ptp_clock *ptp)









{









	if (ptp_vclock_in_use(ptp)) {









		pr_err("ptp: virtual clock in use\n");









		return -EBUSY;









	}



















	ptp->defunct = 1;









	wake_up_interruptible(&ptp->tsev_wq);



















	kfree(ptp->vclock_index);



















	if (ptp->kworker) {









		kthread_cancel_delayed_work_sync(&ptp->aux_work);









		kthread_destroy_worker(ptp->kworker);