* [PATCH v3 0/3] ptp: IEEE 1588 clock support
@ 2010-05-14 16:44 Richard Cochran
2010-05-14 16:45 ` [PATCH v3 1/3] ptp: Added a brand new class driver for ptp clocks Richard Cochran
` (2 more replies)
0 siblings, 3 replies; 11+ messages in thread
From: Richard Cochran @ 2010-05-14 16:44 UTC (permalink / raw)
To: netdev; +Cc: linuxppc-dev, devicetree-discuss
Now and again there has been talk on this list of adding PTP support
into Linux. One part of the picture is already in place, the
SO_TIMESTAMPING API for hardware time stamping. This patch set offers
the missing second part needed for complete IEEE 1588 support.
The only feature still to be implemented is the hook into the PPS
subsystem, to synchronize the Linux clock to the PTP clock.
Enjoy,
Richard
* Patch ChangeLog
** v3
*** general
- Added documentation on writing clock drivers.
- Added the ioctls for the ancillary clock features.
- Changed wrong subsys_initcall() to module_init() in clock drivers.
- Removed the (too coarse) character device mutex.
- Setting the clock now requires CAP_SYS_TIME.
*** gianfar
- Added alarm feature.
- Added device tree node binding description.
- Added fine grain locking of the clock registers.
- Added the external time stamp feature.
- Added white space for better style.
- Coverted base+offset to structure pointers for register access.
- When removing the driver, we now disable all PTP functions.
** v2
- Changed clock list from a static array into a dynamic list. Also,
use a bitmap to manage the clock's minor numbers.
- Replaced character device semaphore with a mutex.
- Drop .ko from module names in Kbuild help.
- Replace deprecated unifdef-y with header-y for user space header file.
- Added links to both of the ptpd patches on sourceforge.
- Gianfar driver now gets parameters from device tree.
- Added API documentation to Documentation/ptp/ptp.txt
Richard Cochran (3):
ptp: Added a brand new class driver for ptp clocks.
ptp: Added a clock that uses the Linux system time.
ptp: Added a clock that uses the eTSEC found on the MPC85xx.
Documentation/powerpc/dts-bindings/fsl/tsec.txt | 56 +++
Documentation/ptp/ptp.txt | 95 ++++
Documentation/ptp/testptp.c | 245 +++++++++++
Documentation/ptp/testptp.mk | 33 ++
arch/powerpc/boot/dts/mpc8313erdb.dts | 14 +
arch/powerpc/boot/dts/p2020ds.dts | 14 +
arch/powerpc/boot/dts/p2020rdb.dts | 14 +
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/net/Makefile | 1 +
drivers/net/gianfar_ptp.c | 521 +++++++++++++++++++++++
drivers/net/gianfar_ptp_reg.h | 113 +++++
drivers/ptp/Kconfig | 51 +++
drivers/ptp/Makefile | 6 +
drivers/ptp/ptp_clock.c | 512 ++++++++++++++++++++++
drivers/ptp/ptp_linux.c | 136 ++++++
include/linux/Kbuild | 1 +
include/linux/ptp_clock.h | 79 ++++
include/linux/ptp_clock_kernel.h | 137 ++++++
kernel/time/ntp.c | 2 +
20 files changed, 2033 insertions(+), 0 deletions(-)
create mode 100644 Documentation/ptp/ptp.txt
create mode 100644 Documentation/ptp/testptp.c
create mode 100644 Documentation/ptp/testptp.mk
create mode 100644 drivers/net/gianfar_ptp.c
create mode 100644 drivers/net/gianfar_ptp_reg.h
create mode 100644 drivers/ptp/Kconfig
create mode 100644 drivers/ptp/Makefile
create mode 100644 drivers/ptp/ptp_clock.c
create mode 100644 drivers/ptp/ptp_linux.c
create mode 100644 include/linux/ptp_clock.h
create mode 100644 include/linux/ptp_clock_kernel.h
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH v3 1/3] ptp: Added a brand new class driver for ptp clocks.
2010-05-14 16:44 [PATCH v3 0/3] ptp: IEEE 1588 clock support Richard Cochran
@ 2010-05-14 16:45 ` Richard Cochran
2010-05-17 15:41 ` Wolfgang Grandegger
2010-05-14 16:46 ` [PATCH v3 2/3] ptp: Added a clock that uses the Linux system time Richard Cochran
2010-05-14 16:46 ` [PATCH v3 3/3] ptp: Added a clock that uses the eTSEC found on the MPC85xx Richard Cochran
2 siblings, 1 reply; 11+ messages in thread
From: Richard Cochran @ 2010-05-14 16:45 UTC (permalink / raw)
To: netdev; +Cc: linuxppc-dev, devicetree-discuss
This patch adds an infrastructure for hardware clocks that implement
IEEE 1588, the Precision Time Protocol (PTP). A class driver offers a
registration method to particular hardware clock drivers. Each clock is
exposed to user space as a character device with ioctls that allow tuning
of the PTP clock.
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
---
Documentation/ptp/ptp.txt | 95 +++++++
Documentation/ptp/testptp.c | 245 ++++++++++++++++++
Documentation/ptp/testptp.mk | 33 +++
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/ptp/Kconfig | 26 ++
drivers/ptp/Makefile | 5 +
drivers/ptp/ptp_clock.c | 512 ++++++++++++++++++++++++++++++++++++++
include/linux/Kbuild | 1 +
include/linux/ptp_clock.h | 79 ++++++
include/linux/ptp_clock_kernel.h | 137 ++++++++++
11 files changed, 1136 insertions(+), 0 deletions(-)
create mode 100644 Documentation/ptp/ptp.txt
create mode 100644 Documentation/ptp/testptp.c
create mode 100644 Documentation/ptp/testptp.mk
create mode 100644 drivers/ptp/Kconfig
create mode 100644 drivers/ptp/Makefile
create mode 100644 drivers/ptp/ptp_clock.c
create mode 100644 include/linux/ptp_clock.h
create mode 100644 include/linux/ptp_clock_kernel.h
diff --git a/Documentation/ptp/ptp.txt b/Documentation/ptp/ptp.txt
new file mode 100644
index 0000000..46858b3
--- /dev/null
+++ b/Documentation/ptp/ptp.txt
@@ -0,0 +1,95 @@
+
+* PTP infrastructure for Linux
+
+ This patch set introduces support for IEEE 1588 PTP clocks in
+ Linux. Together with the SO_TIMESTAMPING socket options, this
+ presents a standardized method for developing PTP user space
+ programs, synchronizing Linux with external clocks, and using the
+ ancillary features of PTP hardware clocks.
+
+ A new class driver exports a kernel interface for specific clock
+ drivers and a user space interface. The infrastructure supports a
+ complete set of PTP functionality.
+
+ + Basic clock operations
+ - Set time
+ - Get time
+ - Shift the clock by a given offset atomically
+ - Adjust clock frequency
+
+ + Ancillary clock features
+ - One short or periodic alarms, with signal delivery to user program
+ - Time stamp external events
+ - Period output signals configurable from user space
+ - Synchronization of the Linux system time via the PPS subsystem
+
+** PTP kernel API
+
+ A PTP clock driver registers itself with the class driver. The
+ class driver handles all of the dealings with user space. The
+ author of a clock driver need only implement the details of
+ programming the clock hardware. The clock driver notifies the class
+ driver of asynchronous events (alarms and external time stamps) via
+ a simple message passing interface.
+
+ The class driver supports multiple PTP clock drivers. In normal use
+ cases, only one PTP clock is needed. However, for testing and
+ development, it can be useful to have more than one clock in a
+ single system, in order to allow performance comparisons.
+
+** PTP user space API
+
+ The class driver creates a character device for each registered PTP
+ clock. User space programs may control the clock using standardized
+ ioctls. A program may query, enable, configure, and disable the
+ ancillary clock features. User space can receive time stamped
+ events via blocking read() and poll(). One shot and periodic
+ signals may be configured via an ioctl API with semantics similar
+ to the POSIX timer_settime() system call.
+
+ As an real life example, the following two patches for ptpd version
+ 1.0.0 demonstrate how the API works.
+
+ https://sourceforge.net/tracker/?func=detail&aid=2992845&group_id=139814&atid=744634
+
+ https://sourceforge.net/tracker/?func=detail&aid=2992847&group_id=139814&atid=744634
+
+** Writing clock drivers
+
+ Clock drivers include include/linux/ptp_clock_kernel.h and register
+ themselves by presenting a 'struct ptp_clock_info' to the
+ registration method. Clock drivers must implement all of the
+ functions in the interface. If a clock does not offer a particular
+ ancillary feature, then the driver should just return -EOPNOTSUPP
+ from those functions.
+
+ Drivers must ensure that all of the methods in interface are
+ reentrant. Since most hardware implementations treat the time value
+ as a 64 bit integer accessed as two 32 bit registers, drivers
+ should use spin_lock_irqsave/spin_unlock_irqrestore to protect
+ against concurrent access. This locking cannot be accomplished in
+ class driver, since the lock may also be needed by the clock
+ driver's interrupt service routine.
+
+** Supported hardware
+
+ + Standard Linux system timer
+ - No special PTP features
+ - For use with software time stamping
+
+ + Freescale eTSEC gianfar
+ - 2 Time stamp external triggers, programmable polarity (opt. interrupt)
+ - 2 Alarm registers (optional interrupt)
+ - 3 Periodic signals (optional interrupt)
+
+ + National DP83640
+ - 6 GPIOs programmable as inputs or outputs
+ - 6 GPIOs with dedicated functions (LED/JTAG/clock) can also be
+ used as general inputs or outputs
+ - GPIO inputs can time stamp external triggers
+ - GPIO outputs can produce periodic signals
+ - 1 interrupt pin
+
+ + Intel IXP465
+ - Auxiliary Slave/Master Mode Snapshot (optional interrupt)
+ - Target Time (optional interrupt)
diff --git a/Documentation/ptp/testptp.c b/Documentation/ptp/testptp.c
new file mode 100644
index 0000000..ed2ceea
--- /dev/null
+++ b/Documentation/ptp/testptp.c
@@ -0,0 +1,245 @@
+/*
+ * PTP 1588 clock support - User space test program
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <linux/ptp_clock.h>
+
+static void handle_alarm(int s)
+{
+ printf("received signal %d \n", s);
+}
+
+static int install_handler(int signum, void (*handler)(int))
+{
+ struct sigaction action;
+ sigset_t mask;
+
+ /* Unblock the signal. */
+ sigemptyset(&mask);
+ sigaddset(&mask, signum);
+ sigprocmask(SIG_UNBLOCK, &mask, NULL);
+
+ /* Install the signal handler. */
+ action.sa_handler = handler;
+ action.sa_flags = 0;
+ sigemptyset(&action.sa_mask);
+ sigaction(signum, &action, NULL);
+
+ return 0;
+}
+
+static void usage (char* progname)
+{
+ fprintf(stderr,
+ "usage: %s [options] \n"
+ " -a val request a one-shot alarm after 'val' seconds \n"
+ " -A val request a periodic alarm every 'val' seconds \n"
+ " -c query the ptp clock's capabilities \n"
+ " -d name device to open \n"
+ " -e val read 'val' external time stamp events \n"
+ " -f val adjust the ptp clock frequency by 'val' PPB \n"
+ " -g get the ptp clock time \n"
+ " -h prints this message \n"
+ " -s set the ptp clock time from the system time \n"
+ " -t val shift the ptp clock time by 'val' seconds \n"
+ " -v query the ptp clock api version \n"
+ ,progname);
+}
+
+int main(int argc,char *argv[])
+{
+ struct ptp_clock_caps caps;
+ struct ptp_clock_timer timer;
+ struct ptp_extts_event event;
+ struct ptp_clock_request request;
+ struct timespec ts;
+ char *progname;
+ int c, cnt, fd, val=0;
+
+ char *device = "/dev/ptp_clock_0";
+ int adjfreq=0x7fffffff;
+ int adjtime=0;
+ int capabilities=0;
+ int extts=0;
+ int gettime=0;
+ int oneshot=0;
+ int periodic=0;
+ int settime=0;
+ int version=0;
+
+ progname = strrchr(argv[0],'/');
+ progname = progname ? 1+progname : argv[0];
+ while (EOF != (c = getopt(argc, argv, "a:A:cd:e:f:ghst:v"))) {
+ switch (c) {
+ case 'a': oneshot = atoi(optarg); break;
+ case 'A': periodic = atoi(optarg); break;
+ case 'c': capabilities = 1; break;
+ case 'd': device = optarg; break;
+ case 'e': extts = atoi(optarg); break;
+ case 'f': adjfreq = atoi(optarg); break;
+ case 'g': gettime = 1; break;
+ case 's': settime = 1; break;
+ case 't': adjtime = atoi(optarg); break;
+ case 'v': version = 1; break;
+ case 'h': usage(progname); return 0;
+ case '?': usage(progname); return -1;
+ default: usage(progname); return -1;
+ }
+ }
+
+ fd = open(device, O_RDWR);
+ if (fd < 0) {
+ fprintf(stderr,"cannot open %s: %s", device, strerror(errno));
+ return -1;
+ }
+
+ if (version) {
+ if (ioctl(fd, PTP_CLOCK_APIVERS, &val)) {
+ perror("PTP_CLOCK_APIVERS");
+ } else {
+ printf("version = 0x%08x \n",val);
+ }
+ }
+
+ if (capabilities) {
+ if (ioctl(fd, PTP_CLOCK_GETCAPS, &caps)) {
+ perror("PTP_CLOCK_GETCAPS");
+ } else {
+ printf("capabilities: \n"
+ " %d maximum frequency adjustment (PPB) \n"
+ " %d programmable alarms \n"
+ " %d external time stamp channels \n"
+ " %d programmable periodic signals \n"
+ " %d pulse per second \n",
+ caps.max_adj,
+ caps.n_alarm,
+ caps.n_ext_ts,
+ caps.n_per_out,
+ caps.pps);
+ }
+ }
+
+ if (0x7fffffff != adjfreq) {
+ if (ioctl(fd, PTP_CLOCK_ADJFREQ, adjfreq)) {
+ perror("PTP_CLOCK_ADJFREQ");
+ } else {
+ puts("frequency adjustment okay");
+ }
+ }
+
+ if (adjtime) {
+ ts.tv_sec = adjtime;
+ ts.tv_nsec = 0;
+ if (ioctl(fd, PTP_CLOCK_ADJTIME, &ts)) {
+ perror("PTP_CLOCK_ADJTIME");
+ } else {
+ puts("time shift okay");
+ }
+ }
+
+ if (gettime) {
+ if (ioctl(fd, PTP_CLOCK_GETTIME, &ts)) {
+ perror("PTP_CLOCK_GETTIME");
+ } else {
+ printf("clock time: %ld.%09ld or %s",
+ ts.tv_sec, ts.tv_nsec, ctime(&ts.tv_sec));
+ }
+ }
+
+ if (settime) {
+ clock_gettime(CLOCK_REALTIME, &ts);
+ if (ioctl(fd, PTP_CLOCK_SETTIME, &ts)) {
+ perror("PTP_CLOCK_SETTIME");
+ } else {
+ puts("set time okay");
+ }
+ }
+
+ if (extts) {
+ memset(&request, 0, sizeof(request));
+ request.type = PTP_REQUEST_EXTTS;
+ request.index = 0;
+ request.flags = PTP_ENABLE_FEATURE;
+ if (ioctl(fd, PTP_FEATURE_REQUEST, &request)) {
+ perror("PTP_FEATURE_REQUEST");
+ extts = 0;
+ } else {
+ puts("set timer okay");
+ }
+ for (; extts; extts--) {
+ cnt = read(fd, &event, sizeof(event));
+ if (cnt != sizeof(event)) {
+ perror("read");
+ break;
+ }
+ printf("event index %d at %ld.%09ld \n", event.index,
+ event.ts.tv_sec, event.ts.tv_nsec);
+ }
+ /* Disable the feature again. */
+ request.flags = 0;
+ if (ioctl(fd, PTP_FEATURE_REQUEST, &request)) {
+ perror("PTP_FEATURE_REQUEST");
+ }
+ }
+
+ if (oneshot) {
+ install_handler(SIGALRM, handle_alarm);
+ memset(&timer, 0, sizeof(timer));
+ timer.signum = SIGALRM;
+ timer.tsp.it_value.tv_sec = oneshot;
+ if (ioctl(fd, PTP_CLOCK_SETTIMER, &timer)) {
+ perror("PTP_CLOCK_SETTIMER");
+ } else {
+ puts("set timer okay");
+ }
+ pause();
+ }
+
+ if (periodic) {
+ install_handler(SIGALRM, handle_alarm);
+ memset(&timer, 0, sizeof(timer));
+ timer.signum = SIGALRM;
+ timer.tsp.it_value.tv_sec = periodic;
+ timer.tsp.it_interval.tv_sec = periodic;
+ if (ioctl(fd, PTP_CLOCK_SETTIMER, &timer)) {
+ perror("PTP_CLOCK_SETTIMER");
+ } else {
+ puts("set timer okay");
+ }
+ while (1) {
+ pause();
+ }
+ }
+
+ close(fd);
+ return 0;
+}
diff --git a/Documentation/ptp/testptp.mk b/Documentation/ptp/testptp.mk
new file mode 100644
index 0000000..4ef2d97
--- /dev/null
+++ b/Documentation/ptp/testptp.mk
@@ -0,0 +1,33 @@
+# PTP 1588 clock support - User space test program
+#
+# Copyright (C) 2010 OMICRON electronics GmbH
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+CC = $(CROSS_COMPILE)gcc
+INC = -I$(KBUILD_OUTPUT)/usr/include
+CFLAGS = -Wall $(INC)
+LDLIBS = -lrt
+PROGS = testptp
+
+all: $(PROGS)
+
+testptp: testptp.o
+
+clean:
+ rm -f testptp.o
+
+distclean: clean
+ rm -f $(PROGS)
diff --git a/drivers/Kconfig b/drivers/Kconfig
index a2b902f..774fbd7 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -52,6 +52,8 @@ source "drivers/spi/Kconfig"
source "drivers/pps/Kconfig"
+source "drivers/ptp/Kconfig"
+
source "drivers/gpio/Kconfig"
source "drivers/w1/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index f42a030..84228bc 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -75,6 +75,7 @@ obj-$(CONFIG_I2O) += message/
obj-$(CONFIG_RTC_LIB) += rtc/
obj-y += i2c/ media/
obj-$(CONFIG_PPS) += pps/
+obj-$(CONFIG_PTP_1588_CLOCK) += ptp/
obj-$(CONFIG_W1) += w1/
obj-$(CONFIG_POWER_SUPPLY) += power/
obj-$(CONFIG_HWMON) += hwmon/
diff --git a/drivers/ptp/Kconfig b/drivers/ptp/Kconfig
new file mode 100644
index 0000000..c80a25b
--- /dev/null
+++ b/drivers/ptp/Kconfig
@@ -0,0 +1,26 @@
+#
+# PTP clock support configuration
+#
+
+menu "PTP clock support"
+
+config PTP_1588_CLOCK
+ tristate "PTP clock support"
+ depends on EXPERIMENTAL
+ help
+ The IEEE 1588 standard defines a method to precisely
+ synchronize distributed clocks over Ethernet networks. The
+ standard defines a Precision Time Protocol (PTP), which can
+ be used to achieve synchronization within a few dozen
+ microseconds. In addition, with the help of special hardware
+ time stamping units, it can be possible to achieve
+ synchronization to within a few hundred nanoseconds.
+
+ This driver adds support for PTP clocks as character
+ devices. If you want to use a PTP clock, then you should
+ also enable at least one clock driver as well.
+
+ To compile this driver as a module, choose M here: the module
+ will be called ptp_clock.
+
+endmenu
diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile
new file mode 100644
index 0000000..b86695c
--- /dev/null
+++ b/drivers/ptp/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for PTP 1588 clock support.
+#
+
+obj-$(CONFIG_PTP_1588_CLOCK) += ptp_clock.o
diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
new file mode 100644
index 0000000..1d94d31
--- /dev/null
+++ b/drivers/ptp/ptp_clock.c
@@ -0,0 +1,512 @@
+/*
+ * PTP 1588 clock support
+ *
+ * Partially adapted from the Linux PPS driver.
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/bitops.h>
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/poll.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+#include <linux/ptp_clock_kernel.h>
+#include <linux/ptp_clock.h>
+
+#define PTP_MAX_ALARMS 4
+#define PTP_MAX_CLOCKS BITS_PER_LONG
+#define PTP_MAX_TIMESTAMPS 128
+
+struct alarm {
+ struct pid *pid;
+ int sig;
+};
+
+struct timestamp_event_queue {
+ struct ptp_extts_event buf[PTP_MAX_TIMESTAMPS];
+ int head;
+ int tail;
+ int overflow;
+};
+
+struct ptp_clock {
+ struct list_head list;
+ struct cdev cdev;
+ struct device *dev;
+ struct ptp_clock_info *info;
+ dev_t devid;
+ int index; /* index into clocks.map, also the minor number */
+
+ struct alarm alarm[PTP_MAX_ALARMS];
+ struct mutex alarm_mux; /* one process at a time setting an alarm */
+
+ struct timestamp_event_queue tsevq; /* simple fifo for time stamps */
+ struct mutex tsevq_mux; /* one process at a time reading the fifo */
+ wait_queue_head_t tsev_wq;
+};
+
+/* private globals */
+
+static const struct file_operations ptp_fops;
+static dev_t ptp_devt;
+static struct class *ptp_class;
+
+static struct {
+ struct list_head list;
+ DECLARE_BITMAP(map, PTP_MAX_CLOCKS);
+} clocks;
+static DEFINE_SPINLOCK(clocks_lock); /* protects 'clocks' */
+
+/* time stamp event queue operations */
+
+static inline int queue_cnt(struct timestamp_event_queue *q)
+{
+ int cnt = q->tail - q->head;
+ return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt;
+}
+
+static inline int queue_free(struct timestamp_event_queue *q)
+{
+ return PTP_MAX_TIMESTAMPS - queue_cnt(q) - 1;
+}
+
+static void enqueue_external_timestamp(struct timestamp_event_queue *queue,
+ struct ptp_clock_event *src)
+{
+ struct ptp_extts_event *dst;
+ u32 remainder;
+
+ dst = &queue->buf[ queue->tail ];
+
+ dst->index = src->index;
+ dst->ts.tv_sec = div_u64_rem(src->timestamp, 1000000000, &remainder);
+ dst->ts.tv_nsec = remainder;
+
+ if (!queue_free(queue))
+ queue->overflow++;
+
+ queue->tail = (queue->tail + 1) % PTP_MAX_TIMESTAMPS;
+}
+
+/* public interface */
+
+struct ptp_clock* ptp_clock_register(struct ptp_clock_info *info)
+{
+ struct ptp_clock *ptp;
+ int err = 0, index, major = MAJOR(ptp_devt);
+ unsigned long flags;
+
+ if (info->n_alarm > PTP_MAX_ALARMS)
+ return ERR_PTR(-EINVAL);
+
+ /* Find a free clock slot and reserve it. */
+ err = -EBUSY;
+ spin_lock_irqsave(&clocks_lock, flags);
+ index = find_first_zero_bit(clocks.map, PTP_MAX_CLOCKS);
+ if (index < PTP_MAX_CLOCKS) {
+ set_bit(index, clocks.map);
+ spin_unlock_irqrestore(&clocks_lock, flags);
+ } else {
+ spin_unlock_irqrestore(&clocks_lock, flags);
+ goto no_clock;
+ }
+
+ /* Initialize a clock structure. */
+ err = -ENOMEM;
+ ptp = kzalloc(sizeof(struct ptp_clock), GFP_KERNEL);
+ if (ptp == NULL)
+ goto no_memory;
+
+ ptp->info = info;
+ ptp->devid = MKDEV(major, index);
+ ptp->index = index;
+ mutex_init(&ptp->alarm_mux);
+ mutex_init(&ptp->tsevq_mux);
+ init_waitqueue_head(&ptp->tsev_wq);
+
+ /* Create a new device in our class. */
+ ptp->dev = device_create(ptp_class, NULL, ptp->devid, ptp,
+ "ptp_clock_%d", ptp->index);
+ if (IS_ERR(ptp->dev))
+ goto no_device;
+
+ dev_set_drvdata(ptp->dev, ptp);
+
+ /* Register a character device. */
+ cdev_init(&ptp->cdev, &ptp_fops);
+ ptp->cdev.owner = info->owner;
+ err = cdev_add(&ptp->cdev, ptp->devid, 1);
+ if (err)
+ goto no_cdev;
+
+ /* Clock is ready, add it into the list. */
+ spin_lock_irqsave(&clocks_lock, flags);
+ list_add(&ptp->list, &clocks.list);
+ spin_unlock_irqrestore(&clocks_lock, flags);
+
+ return ptp;
+
+no_cdev:
+ device_destroy(ptp_class, ptp->devid);
+no_device:
+ mutex_destroy(&ptp->alarm_mux);
+ mutex_destroy(&ptp->tsevq_mux);
+ kfree(ptp);
+no_memory:
+ spin_lock_irqsave(&clocks_lock, flags);
+ clear_bit(index, clocks.map);
+ spin_unlock_irqrestore(&clocks_lock, flags);
+no_clock:
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL(ptp_clock_register);
+
+int ptp_clock_unregister(struct ptp_clock *ptp)
+{
+ unsigned long flags;
+
+ /* Release the clock's resources. */
+ cdev_del(&ptp->cdev);
+ device_destroy(ptp_class, ptp->devid);
+ mutex_destroy(&ptp->alarm_mux);
+ mutex_destroy(&ptp->tsevq_mux);
+
+ /* Remove the clock from the list. */
+ spin_lock_irqsave(&clocks_lock, flags);
+ list_del(&ptp->list);
+ clear_bit(ptp->index, clocks.map);
+ spin_unlock_irqrestore(&clocks_lock, flags);
+
+ kfree(ptp);
+
+ return 0;
+}
+EXPORT_SYMBOL(ptp_clock_unregister);
+
+void ptp_clock_event(struct ptp_clock *ptp, struct ptp_clock_event *event)
+{
+ switch (event->type) {
+
+ case PTP_CLOCK_ALARM:
+ kill_pid(ptp->alarm[ event->index ].pid,
+ ptp->alarm[ event->index ].sig, 1);
+ break;
+
+ case PTP_CLOCK_EXTTS:
+ enqueue_external_timestamp(&ptp->tsevq, event);
+ wake_up_interruptible(&ptp->tsev_wq);
+ break;
+
+ case PTP_CLOCK_PPS:
+ break;
+ }
+}
+EXPORT_SYMBOL(ptp_clock_event);
+
+/* character device operations */
+
+static int ptp_ioctl(struct inode *node, struct file *fp,
+ unsigned int cmd, unsigned long arg)
+{
+ struct ptp_clock_caps caps;
+ struct ptp_clock_request req;
+ struct ptp_clock_timer timer;
+ struct ptp_clock *ptp = fp->private_data;
+ struct ptp_clock_info *ops = ptp->info;
+ void *priv = ops->priv;
+ struct timespec ts;
+ int flags, index;
+ int err = 0;
+
+ switch (cmd) {
+
+ case PTP_CLOCK_APIVERS:
+ err = put_user(PTP_CLOCK_VERSION, (u32 __user*)arg);
+ break;
+
+ case PTP_CLOCK_ADJFREQ:
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+ err = ops->adjfreq(priv, arg);
+ break;
+
+ case PTP_CLOCK_ADJTIME:
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+ if (copy_from_user(&ts, (void __user*)arg, sizeof(ts)))
+ err = -EFAULT;
+ else
+ err = ops->adjtime(priv, &ts);
+ break;
+
+ case PTP_CLOCK_GETTIME:
+ err = ops->gettime(priv, &ts);
+ if (err)
+ break;
+ err = copy_to_user((void __user*)arg, &ts, sizeof(ts));
+ break;
+
+ case PTP_CLOCK_SETTIME:
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+ if (copy_from_user(&ts, (void __user*)arg, sizeof(ts)))
+ err = -EFAULT;
+ else
+ err = ops->settime(priv, &ts);
+ break;
+
+ case PTP_CLOCK_GETCAPS:
+ memset(&caps, 0, sizeof(caps));
+ caps.max_adj = ptp->info->max_adj;
+ caps.n_alarm = ptp->info->n_alarm;
+ caps.n_ext_ts = ptp->info->n_ext_ts;
+ caps.n_per_out = ptp->info->n_per_out;
+ caps.pps = ptp->info->pps;
+ err = copy_to_user((void __user*)arg, &caps, sizeof(caps));
+ break;
+
+ case PTP_CLOCK_GETTIMER:
+ if (copy_from_user(&timer, (void __user*)arg, sizeof(timer))) {
+ err = -EFAULT;
+ break;
+ }
+ index = timer.alarm_index;
+ if (index < 0 || index >= ptp->info->n_alarm) {
+ err = -EINVAL;
+ break;
+ }
+ err = ops->gettimer(priv, index, &timer.tsp);
+ if (err)
+ break;
+ err = copy_to_user((void __user*)arg, &timer, sizeof(timer));
+ break;
+
+ case PTP_CLOCK_SETTIMER:
+ if (copy_from_user(&timer, (void __user*)arg, sizeof(timer))) {
+ err = -EFAULT;
+ break;
+ }
+ index = timer.alarm_index;
+ if (index < 0 || index >= ptp->info->n_alarm) {
+ err = -EINVAL;
+ break;
+ }
+ if (!valid_signal(timer.signum))
+ return -EINVAL;
+ flags = timer.flags;
+ if (flags & (flags != TIMER_ABSTIME)) {
+ err = -EINVAL;
+ break;
+ }
+ if (mutex_lock_interruptible(&ptp->alarm_mux))
+ return -ERESTARTSYS;
+
+ if (ptp->alarm[index].pid)
+ put_pid(ptp->alarm[index].pid);
+
+ ptp->alarm[index].pid = get_pid(task_pid(current));
+ ptp->alarm[index].sig = timer.signum;
+ err = ops->settimer(priv, index, flags, &timer.tsp);
+
+ mutex_unlock(&ptp->alarm_mux);
+ break;
+
+ case PTP_FEATURE_REQUEST:
+ if (copy_from_user(&req, (void __user*)arg, sizeof(req))) {
+ err = -EFAULT;
+ break;
+ }
+ switch (req.type) {
+ case PTP_REQUEST_EXTTS:
+ case PTP_REQUEST_PEROUT:
+ break;
+ case PTP_REQUEST_PPS:
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+ break;
+ default:
+ err = -EINVAL;
+ break;
+ }
+ if (err)
+ break;
+ err = ops->enable(priv, &req,
+ req.flags & PTP_ENABLE_FEATURE ? 1 : 0);
+ break;
+
+ default:
+ err = -ENOTTY;
+ break;
+ }
+ return err;
+}
+
+static int ptp_open(struct inode *inode, struct file *fp)
+{
+ struct ptp_clock *ptp;
+ ptp = container_of(inode->i_cdev, struct ptp_clock, cdev);
+
+ fp->private_data = ptp;
+
+ return 0;
+}
+
+static unsigned int ptp_poll(struct file *fp, poll_table *wait)
+{
+ struct ptp_clock *ptp = fp->private_data;
+
+ poll_wait(fp, &ptp->tsev_wq, wait);
+
+ return queue_cnt(&ptp->tsevq) ? POLLIN : 0;
+}
+
+static ssize_t ptp_read(struct file *fp, char __user *buf,
+ size_t cnt, loff_t *off)
+{
+ struct ptp_clock *ptp = fp->private_data;
+ struct timestamp_event_queue *queue = &ptp->tsevq;
+ struct ptp_extts_event *event;
+ size_t qcnt;
+
+ if (mutex_lock_interruptible(&ptp->tsevq_mux))
+ return -ERESTARTSYS;
+
+ cnt = cnt / sizeof(struct ptp_extts_event);
+
+ if (wait_event_interruptible(ptp->tsev_wq,
+ (qcnt = queue_cnt(&ptp->tsevq)))) {
+ mutex_unlock(&ptp->tsevq_mux);
+ return -ERESTARTSYS;
+ }
+
+ if (cnt > qcnt)
+ cnt = qcnt;
+
+ event = &queue->buf[ queue->head ];
+
+ if (copy_to_user(buf, event, cnt * sizeof(struct ptp_extts_event))) {
+ mutex_unlock(&ptp->tsevq_mux);
+ return -EFAULT;
+ }
+ queue->head = (queue->head + cnt) % PTP_MAX_TIMESTAMPS;
+
+ mutex_unlock(&ptp->tsevq_mux);
+
+ return cnt * sizeof(struct ptp_extts_event);
+}
+
+static int ptp_release(struct inode *inode, struct file *fp)
+{
+ struct ptp_clock *ptp;
+ struct itimerspec ts = {{0,0},{0,0}};
+ int i;
+
+ ptp = container_of(inode->i_cdev, struct ptp_clock, cdev);
+
+ for (i = 0; i < ptp->info->n_alarm; i++) {
+ if (ptp->alarm[i].pid) {
+ ptp->info->settimer(ptp->info->priv, i, 0, &ts);
+ put_pid(ptp->alarm[i].pid);
+ ptp->alarm[i].pid = NULL;
+ }
+ }
+ return 0;
+}
+
+static const struct file_operations ptp_fops = {
+ .owner = THIS_MODULE,
+ .ioctl = ptp_ioctl,
+ .open = ptp_open,
+ .poll = ptp_poll,
+ .read = ptp_read,
+ .release = ptp_release,
+};
+
+/* sysfs */
+
+static ssize_t ptp_show_status(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ptp_clock *ptp = dev_get_drvdata(dev);
+ return sprintf(buf,
+ "maximum adjustment: %d\n"
+ "programmable alarms: %d\n"
+ "external timestamps: %d\n"
+ "periodic outputs: %d\n"
+ "has pps: %d\n"
+ "device index: %d\n"
+ ,ptp->info->max_adj
+ ,ptp->info->n_alarm
+ ,ptp->info->n_ext_ts
+ ,ptp->info->n_per_out
+ ,ptp->info->pps
+ ,ptp->index);
+}
+
+struct device_attribute ptp_attrs[] = {
+ __ATTR(capabilities, S_IRUGO, ptp_show_status, NULL),
+ __ATTR_NULL,
+};
+
+/* module operations */
+
+static void __exit ptp_exit(void)
+{
+ class_destroy(ptp_class);
+ unregister_chrdev_region(ptp_devt, PTP_MAX_CLOCKS);
+}
+
+static int __init ptp_init(void)
+{
+ int err;
+
+ INIT_LIST_HEAD(&clocks.list);
+
+ ptp_class = class_create(THIS_MODULE, "ptp");
+ if (!ptp_class) {
+ printk(KERN_ERR "ptp: failed to allocate class\n");
+ return -ENOMEM;
+ }
+ ptp_class->dev_attrs = ptp_attrs;
+
+ err = alloc_chrdev_region(&ptp_devt, 0, PTP_MAX_CLOCKS, "ptp");
+ if (err < 0) {
+ printk(KERN_ERR "ptp: failed to allocate char device region\n");
+ goto no_region;
+ }
+
+ pr_info("PTP clock support registered\n");
+ return 0;
+
+no_region:
+ class_destroy(ptp_class);
+ return err;
+}
+
+subsys_initcall(ptp_init);
+module_exit(ptp_exit);
+
+MODULE_AUTHOR("Richard Cochran <richard.cochran@omicron.at>");
+MODULE_DESCRIPTION("PTP clocks support");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/Kbuild b/include/linux/Kbuild
index 2fc8e14..9959fe4 100644
--- a/include/linux/Kbuild
+++ b/include/linux/Kbuild
@@ -140,6 +140,7 @@ header-y += pkt_sched.h
header-y += posix_types.h
header-y += ppdev.h
header-y += prctl.h
+header-y += ptp_clock.h
header-y += qnxtypes.h
header-y += qnx4_fs.h
header-y += radeonfb.h
diff --git a/include/linux/ptp_clock.h b/include/linux/ptp_clock.h
new file mode 100644
index 0000000..5a509c5
--- /dev/null
+++ b/include/linux/ptp_clock.h
@@ -0,0 +1,79 @@
+/*
+ * PTP 1588 clock support - user space interface
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef _PTP_CLOCK_H_
+#define _PTP_CLOCK_H_
+
+#include <linux/ioctl.h>
+#include <linux/types.h>
+
+#define PTP_ENABLE_FEATURE (1<<0)
+#define PTP_RISING_EDGE (1<<1)
+#define PTP_FALLING_EDGE (1<<2)
+
+enum ptp_request_types {
+ PTP_REQUEST_EXTTS,
+ PTP_REQUEST_PEROUT,
+ PTP_REQUEST_PPS,
+};
+
+struct ptp_clock_caps {
+ __s32 max_adj; /* Maximum frequency adjustment, parts per billon. */
+ int n_alarm; /* Number of programmable alarms. */
+ int n_ext_ts; /* Number of external time stamp channels. */
+ int n_per_out; /* Number of programmable periodic signals. */
+ int pps; /* Whether the clock supports a PPS callback. */
+};
+
+struct ptp_clock_timer {
+ int alarm_index; /* Which alarm to query or configure. */
+ int signum; /* Requested signal. */
+ int flags; /* Zero or TIMER_ABSTIME, see TIMER_SETTIME(2) */
+ struct itimerspec tsp; /* See TIMER_SETTIME(2) */
+};
+
+struct ptp_clock_request {
+ int type; /* One of the ptp_request_types enumeration values. */
+ int index; /* Which channel to configure. */
+ struct timespec ts; /* For period signals, the desired period. */
+ int flags; /* Bit field for PTP_ENABLE_FEATURE or other flags. */
+};
+
+struct ptp_extts_event {
+ int index;
+ struct timespec ts;
+};
+
+#define PTP_CLOCK_VERSION 0x00000001
+
+#define PTP_CLK_MAGIC '='
+
+#define PTP_CLOCK_APIVERS _IOR (PTP_CLK_MAGIC, 1, __u32)
+#define PTP_CLOCK_ADJFREQ _IO (PTP_CLK_MAGIC, 2)
+#define PTP_CLOCK_ADJTIME _IOW (PTP_CLK_MAGIC, 3, struct timespec)
+#define PTP_CLOCK_GETTIME _IOR (PTP_CLK_MAGIC, 4, struct timespec)
+#define PTP_CLOCK_SETTIME _IOW (PTP_CLK_MAGIC, 5, struct timespec)
+
+#define PTP_CLOCK_GETCAPS _IOR (PTP_CLK_MAGIC, 6, struct ptp_clock_caps)
+#define PTP_CLOCK_GETTIMER _IOWR (PTP_CLK_MAGIC, 7, struct ptp_clock_timer)
+#define PTP_CLOCK_SETTIMER _IOW (PTP_CLK_MAGIC, 8, struct ptp_clock_timer)
+#define PTP_FEATURE_REQUEST _IOW (PTP_CLK_MAGIC, 9, struct ptp_clock_request)
+
+#endif
diff --git a/include/linux/ptp_clock_kernel.h b/include/linux/ptp_clock_kernel.h
new file mode 100644
index 0000000..b1fb2a7
--- /dev/null
+++ b/include/linux/ptp_clock_kernel.h
@@ -0,0 +1,137 @@
+/*
+ * PTP 1588 clock support
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef _PTP_CLOCK_KERNEL_H_
+#define _PTP_CLOCK_KERNEL_H_
+
+#include <linux/ptp_clock.h>
+
+/**
+ * struct ptp_clock_info - decribes a PTP hardware clock
+ *
+ * @owner: The clock driver should set to THIS_MODULE.
+ * @name: A short name to identify the clock.
+ * @max_adj: The maximum possible frequency adjustment, in parts per billon.
+ * @n_alarm: The number of programmable alarms.
+ * @n_ext_ts: The number of external time stamp channels.
+ * @n_per_out: The number of programmable periodic signals.
+ * @pps: Indicates whether the clock supports a PPS callback.
+ * @priv: Passed to the clock operations, for the driver's private use.
+ *
+ * clock operations
+ *
+ * @adjfreq: Adjusts the frequency of the hardware clock.
+ * parameter delta: Desired period change in parts per billion.
+ *
+ * @adjtime: Shifts the time of the hardware clock.
+ * parameter ts: Desired change in seconds and nanoseconds.
+ *
+ * @gettime: Reads the current time from the hardware clock.
+ * parameter ts: Holds the result.
+ *
+ * @settime: Set the current time on the hardware clock.
+ * parameter ts: Time value to set.
+ *
+ * @gettimer: Reads the time remaining from the given timer.
+ * parameter index: Which alarm to query.
+ * parameter ts: Holds the result.
+ *
+ * @settimer: Arms the given timer for periodic or one shot operation.
+ * parameter index: Which alarm to set.
+ * parameter abs: TIMER_ABSTIME, or zero for relative timer.
+ * parameter ts: Alarm time and period to set.
+ *
+ * @enable: Request driver to enable or disable an ancillary feature.
+ * parameter request: Desired resource to enable or disable.
+ * parameter on: Caller passes one to enable or zero to disable.
+ *
+ * The callbacks must all return zero on success, non-zero otherwise.
+ */
+
+struct ptp_clock_info {
+ struct module *owner;
+ char name[16];
+ s32 max_adj;
+ int n_alarm;
+ int n_ext_ts;
+ int n_per_out;
+ int pps;
+ void *priv;
+ int (*adjfreq)(void *priv, s32 delta);
+ int (*adjtime)(void *priv, struct timespec *ts);
+ int (*gettime)(void *priv, struct timespec *ts);
+ int (*settime)(void *priv, struct timespec *ts);
+ int (*gettimer)(void *priv, int index, struct itimerspec *ts);
+ int (*settimer)(void *priv, int index, int abs, struct itimerspec *ts);
+ int (*enable)(void *priv, struct ptp_clock_request *request, int on);
+};
+
+struct ptp_clock;
+
+/**
+ * ptp_clock_register() - register a PTP hardware clock driver
+ *
+ * @info: Structure describing the new clock.
+ */
+
+extern struct ptp_clock* ptp_clock_register(struct ptp_clock_info *info);
+
+/**
+ * ptp_clock_unregister() - unregister a PTP hardware clock driver
+ *
+ * @ptp: The clock to remove from service.
+ */
+
+extern int ptp_clock_unregister(struct ptp_clock *ptp);
+
+
+enum ptp_clock_events {
+ PTP_CLOCK_ALARM,
+ PTP_CLOCK_EXTTS,
+ PTP_CLOCK_PPS,
+};
+
+/**
+ * struct ptp_clock_event - decribes a PTP hardware clock event
+ *
+ * @type: One of the ptp_clock_events enumeration values.
+ * @index: Identifies the source of the event.
+ * @timestamp: When the event occured.
+ */
+
+struct ptp_clock_event {
+ int type;
+ int index;
+ u64 timestamp;
+};
+
+/**
+ * ptp_clock_event() - notify the PTP layer about an event
+ *
+ * This function should only be called from interrupt context.
+ *
+ * @ptp: The clock obtained from ptp_clock_register().
+ * @event: Message structure describing the event.
+ */
+
+extern void ptp_clock_event(struct ptp_clock *ptp,
+ struct ptp_clock_event *event);
+
+#endif
--
1.6.3.3
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH v3 2/3] ptp: Added a clock that uses the Linux system time.
2010-05-14 16:44 [PATCH v3 0/3] ptp: IEEE 1588 clock support Richard Cochran
2010-05-14 16:45 ` [PATCH v3 1/3] ptp: Added a brand new class driver for ptp clocks Richard Cochran
@ 2010-05-14 16:46 ` Richard Cochran
2010-05-14 16:46 ` [PATCH v3 3/3] ptp: Added a clock that uses the eTSEC found on the MPC85xx Richard Cochran
2 siblings, 0 replies; 11+ messages in thread
From: Richard Cochran @ 2010-05-14 16:46 UTC (permalink / raw)
To: netdev; +Cc: linuxppc-dev, devicetree-discuss
This PTP clock simply uses the NTP time adjustment system calls. The
driver can be used in systems that lack a special hardware PTP clock.
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
---
drivers/ptp/Kconfig | 12 ++++
drivers/ptp/Makefile | 1 +
drivers/ptp/ptp_linux.c | 136 +++++++++++++++++++++++++++++++++++++++++++++++
kernel/time/ntp.c | 2 +
4 files changed, 151 insertions(+), 0 deletions(-)
create mode 100644 drivers/ptp/ptp_linux.c
diff --git a/drivers/ptp/Kconfig b/drivers/ptp/Kconfig
index c80a25b..9390d44 100644
--- a/drivers/ptp/Kconfig
+++ b/drivers/ptp/Kconfig
@@ -23,4 +23,16 @@ config PTP_1588_CLOCK
To compile this driver as a module, choose M here: the module
will be called ptp_clock.
+config PTP_1588_CLOCK_LINUX
+ tristate "Linux system timer as PTP clock"
+ depends on PTP_1588_CLOCK
+ help
+ This driver adds support for using the standard Linux time
+ source as a PTP clock. This clock is only useful if your PTP
+ programs are using software time stamps for the PTP Ethernet
+ packets.
+
+ To compile this driver as a module, choose M here: the module
+ will be called ptp_linux.
+
endmenu
diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile
index b86695c..1651d52 100644
--- a/drivers/ptp/Makefile
+++ b/drivers/ptp/Makefile
@@ -3,3 +3,4 @@
#
obj-$(CONFIG_PTP_1588_CLOCK) += ptp_clock.o
+obj-$(CONFIG_PTP_1588_CLOCK_LINUX) += ptp_linux.o
diff --git a/drivers/ptp/ptp_linux.c b/drivers/ptp/ptp_linux.c
new file mode 100644
index 0000000..f0dbfc6
--- /dev/null
+++ b/drivers/ptp/ptp_linux.c
@@ -0,0 +1,136 @@
+/*
+ * PTP 1588 clock using the Linux system clock
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/hrtimer.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/timex.h>
+
+#include <linux/ptp_clock_kernel.h>
+
+static struct ptp_clock *linux_clock;
+
+DEFINE_SPINLOCK(adjtime_lock);
+
+static int ptp_linux_adjfreq(void *priv, s32 delta)
+{
+ struct timex txc;
+ s64 tmp = delta;
+ int err;
+ txc.freq = div_s64(tmp<<16, 1000);
+ txc.modes = ADJ_FREQUENCY;
+ err = do_adjtimex(&txc);
+ return err < 0 ? err : 0;
+}
+
+static int ptp_linux_adjtime(void *priv, struct timespec *ts)
+{
+ s64 delta;
+ ktime_t now;
+ struct timespec t2;
+ unsigned long flags;
+ int err;
+
+ delta = 1000000000LL * ts->tv_sec + ts->tv_nsec;
+
+ spin_lock_irqsave(&adjtime_lock, flags);
+
+ now = ktime_get_real();
+
+ now = delta < 0 ? ktime_sub_ns(now,-delta) : ktime_add_ns(now,delta);
+
+ t2 = ktime_to_timespec(now);
+
+ err = do_settimeofday(&t2);
+
+ spin_unlock_irqrestore(&adjtime_lock, flags);
+
+ return err;
+}
+
+static int ptp_linux_gettime(void *priv, struct timespec *ts)
+{
+ getnstimeofday(ts);
+ return 0;
+}
+
+static int ptp_linux_settime(void *priv, struct timespec *ts)
+{
+ return do_settimeofday(ts);
+}
+
+static int ptp_linux_gettimer(void *priv, int index, struct itimerspec *ts)
+{
+ /* We do not offer any ancillary features at all. */
+ return -EOPNOTSUPP;
+}
+
+static int ptp_linux_settimer(void *p, int i, int abs, struct itimerspec *ts)
+{
+ /* We do not offer any ancillary features at all. */
+ return -EOPNOTSUPP;
+}
+
+static int ptp_linux_enable(void *priv, struct ptp_clock_request *rq, int on)
+{
+ /* We do not offer any ancillary features at all. */
+ return -EOPNOTSUPP;
+}
+
+static struct ptp_clock_info ptp_linux_caps = {
+ .owner = THIS_MODULE,
+ .name = "Linux timer",
+ .max_adj = 512000,
+ .n_alarm = 0,
+ .n_ext_ts = 0,
+ .n_per_out = 0,
+ .pps = 0,
+ .priv = NULL,
+ .adjfreq = ptp_linux_adjfreq,
+ .adjtime = ptp_linux_adjtime,
+ .gettime = ptp_linux_gettime,
+ .settime = ptp_linux_settime,
+ .gettimer = ptp_linux_gettimer,
+ .settimer = ptp_linux_settimer,
+ .enable = ptp_linux_enable,
+};
+
+/* module operations */
+
+static void __exit ptp_linux_exit(void)
+{
+ ptp_clock_unregister(linux_clock);
+}
+
+static int __init ptp_linux_init(void)
+{
+ linux_clock = ptp_clock_register(&ptp_linux_caps);
+
+ return IS_ERR(linux_clock) ? PTR_ERR(linux_clock) : 0;
+}
+
+module_init(ptp_linux_init);
+module_exit(ptp_linux_exit);
+
+MODULE_AUTHOR("Richard Cochran <richard.cochran@omicron.at>");
+MODULE_DESCRIPTION("PTP clock using the Linux system timer");
+MODULE_LICENSE("GPL");
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 7c0f180..efd1ff8 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -14,6 +14,7 @@
#include <linux/timex.h>
#include <linux/time.h>
#include <linux/mm.h>
+#include <linux/module.h>
/*
* NTP timekeeping variables:
@@ -535,6 +536,7 @@ int do_adjtimex(struct timex *txc)
return result;
}
+EXPORT_SYMBOL(do_adjtimex);
static int __init ntp_tick_adj_setup(char *str)
{
--
1.6.3.3
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH v3 3/3] ptp: Added a clock that uses the eTSEC found on the MPC85xx.
2010-05-14 16:44 [PATCH v3 0/3] ptp: IEEE 1588 clock support Richard Cochran
2010-05-14 16:45 ` [PATCH v3 1/3] ptp: Added a brand new class driver for ptp clocks Richard Cochran
2010-05-14 16:46 ` [PATCH v3 2/3] ptp: Added a clock that uses the Linux system time Richard Cochran
@ 2010-05-14 16:46 ` Richard Cochran
2010-05-14 17:46 ` Scott Wood
2010-05-17 15:41 ` Wolfgang Grandegger
2 siblings, 2 replies; 11+ messages in thread
From: Richard Cochran @ 2010-05-14 16:46 UTC (permalink / raw)
To: netdev; +Cc: linuxppc-dev, devicetree-discuss
The eTSEC includes a PTP clock with quite a few features. This patch adds
support for the basic clock adjustment functions, plus two external time
stamps and one alarm.
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
---
Documentation/powerpc/dts-bindings/fsl/tsec.txt | 56 +++
arch/powerpc/boot/dts/mpc8313erdb.dts | 14 +
arch/powerpc/boot/dts/p2020ds.dts | 14 +
arch/powerpc/boot/dts/p2020rdb.dts | 14 +
drivers/net/Makefile | 1 +
drivers/net/gianfar_ptp.c | 521 +++++++++++++++++++++++
drivers/net/gianfar_ptp_reg.h | 113 +++++
drivers/ptp/Kconfig | 13 +
8 files changed, 746 insertions(+), 0 deletions(-)
create mode 100644 drivers/net/gianfar_ptp.c
create mode 100644 drivers/net/gianfar_ptp_reg.h
diff --git a/Documentation/powerpc/dts-bindings/fsl/tsec.txt b/Documentation/powerpc/dts-bindings/fsl/tsec.txt
index edb7ae1..b09ba66 100644
--- a/Documentation/powerpc/dts-bindings/fsl/tsec.txt
+++ b/Documentation/powerpc/dts-bindings/fsl/tsec.txt
@@ -74,3 +74,59 @@ Example:
interrupt-parent = <&mpic>;
phy-handle = <&phy0>
};
+
+* Gianfar PTP clock nodes
+
+General Properties:
+
+ - device_type Should be "ptp_clock"
+ - model Model of the device. Must be "eTSEC"
+ - reg Offset and length of the register set for the device
+ - interrupts There should be at least two and as many as four
+ PTP related interrupts
+
+Clock Properties:
+
+ - tclk_period Timer reference clock period in nanoseconds.
+ - tmr_prsc Prescaler, divides the output clock.
+ - tmr_add Frequency compensation value.
+ - cksel 0= external clock, 1= eTSEC system clock, 3= RTC clock input.
+ Currently the driver only supports choice "1".
+ - tmr_fiper1 Fixed interval period pulse generator.
+ - tmr_fiper2 Fixed interval period pulse generator.
+
+ These properties set the operational parameters for the PTP
+ clock. You must choose these carefully for the clock to work right.
+ Here is how to figure good values:
+
+ TimerOsc = system clock MHz
+ tclk_period = desired clock period nanoseconds
+ NominalFreq = 1000 / tclk_period MHz
+ FreqDivRatio = TimerOsc / NominalFreq (must be greater that 1.0)
+ tmr_add = ceil(2^32 / FreqDivRatio)
+ OutputClock = NominalFreq / tmr_prsc MHz
+ PulseWidth = 1 / OutputClock microseconds
+ FiperFreq1 = desired frequency in Hz
+ FiperDiv1 = 1000000 * OutputClock / FiperFreq1
+ tmr_fiper1 = tmr_prsc * tclk_period * FiperDiv1 - tclk_period
+
+ The calculation for tmr_fiper2 is the same as for tmr_fiper1. The
+ driver expects that tmr_fiper1 will be correctly set to produce a 1
+ Pulse Per Second (PPS) signal, since this will be offered to the PPS
+ subsystem to synchronize the Linux clock.
+
+Example:
+
+ ptp_clock@24E00 {
+ device_type = "ptp_clock";
+ model = "eTSEC";
+ reg = <0x24E00 0xB0>;
+ interrupts = <12 0x8 13 0x8>;
+ interrupt-parent = < &ipic >;
+ tclk_period = <10>;
+ tmr_prsc = <100>;
+ tmr_add = <0x999999A4>;
+ cksel = <0x1>;
+ tmr_fiper1 = <0x3B9AC9F6>;
+ tmr_fiper2 = <0x00018696>;
+ };
diff --git a/arch/powerpc/boot/dts/mpc8313erdb.dts b/arch/powerpc/boot/dts/mpc8313erdb.dts
index 183f2aa..6be6b16 100644
--- a/arch/powerpc/boot/dts/mpc8313erdb.dts
+++ b/arch/powerpc/boot/dts/mpc8313erdb.dts
@@ -208,6 +208,20 @@
sleep = <&pmc 0x00300000>;
};
+ ptp_clock@24E00 {
+ device_type = "ptp_clock";
+ model = "eTSEC";
+ reg = <0x24E00 0xB0>;
+ interrupts = <12 0x8 13 0x8>;
+ interrupt-parent = < &ipic >;
+ tclk_period = <10>;
+ tmr_prsc = <100>;
+ tmr_add = <0x999999A4>;
+ cksel = <0x1>;
+ tmr_fiper1 = <0x3B9AC9F6>;
+ tmr_fiper2 = <0x00018696>;
+ };
+
enet0: ethernet@24000 {
#address-cells = <1>;
#size-cells = <1>;
diff --git a/arch/powerpc/boot/dts/p2020ds.dts b/arch/powerpc/boot/dts/p2020ds.dts
index 1101914..f72353a 100644
--- a/arch/powerpc/boot/dts/p2020ds.dts
+++ b/arch/powerpc/boot/dts/p2020ds.dts
@@ -336,6 +336,20 @@
phy_type = "ulpi";
};
+ ptp_clock@24E00 {
+ device_type = "ptp_clock";
+ model = "eTSEC";
+ reg = <0x24E00 0xB0>;
+ interrupts = <68 2 69 2 70 2>;
+ interrupt-parent = < &mpic >;
+ tclk_period = <5>;
+ tmr_prsc = <200>;
+ tmr_add = <0xCCCCCCCD>;
+ cksel = <1>;
+ tmr_fiper1 = <0x3B9AC9FB>;
+ tmr_fiper2 = <0x0001869B>;
+ };
+
enet0: ethernet@24000 {
#address-cells = <1>;
#size-cells = <1>;
diff --git a/arch/powerpc/boot/dts/p2020rdb.dts b/arch/powerpc/boot/dts/p2020rdb.dts
index da4cb0d..3eb9e65 100644
--- a/arch/powerpc/boot/dts/p2020rdb.dts
+++ b/arch/powerpc/boot/dts/p2020rdb.dts
@@ -396,6 +396,20 @@
phy_type = "ulpi";
};
+ ptp_clock@24E00 {
+ device_type = "ptp_clock";
+ model = "eTSEC";
+ reg = <0x24E00 0xB0>;
+ interrupts = <68 2 69 2 70 2>;
+ interrupt-parent = < &mpic >;
+ tclk_period = <5>;
+ tmr_prsc = <200>;
+ tmr_add = <0xCCCCCCCD>;
+ cksel = <1>;
+ tmr_fiper1 = <0x3B9AC9FB>;
+ tmr_fiper2 = <0x0001869B>;
+ };
+
enet0: ethernet@24000 {
#address-cells = <1>;
#size-cells = <1>;
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 0a0512a..389c0d9 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_ATL2) += atlx/
obj-$(CONFIG_ATL1E) += atl1e/
obj-$(CONFIG_ATL1C) += atl1c/
obj-$(CONFIG_GIANFAR) += gianfar_driver.o
+obj-$(CONFIG_PTP_1588_CLOCK_GIANFAR) += gianfar_ptp.o
obj-$(CONFIG_TEHUTI) += tehuti.o
obj-$(CONFIG_ENIC) += enic/
obj-$(CONFIG_JME) += jme.o
diff --git a/drivers/net/gianfar_ptp.c b/drivers/net/gianfar_ptp.c
new file mode 100644
index 0000000..46797aa
--- /dev/null
+++ b/drivers/net/gianfar_ptp.c
@@ -0,0 +1,521 @@
+/*
+ * PTP 1588 clock using the eTSEC
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/device.h>
+#include <linux/hrtimer.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/timex.h>
+#include <asm/io.h>
+
+#include <linux/ptp_clock_kernel.h>
+
+#include "gianfar_ptp_reg.h"
+#include "gianfar.h"
+
+#define DRIVER "gianfar_ptp"
+#define N_ALARM 1 /* first alarm is used internally to reset fipers */
+#define N_EXT_TS 2
+#define N_IRQS 2
+#define REG_SIZE sizeof(struct gianfar_ptp_registers)
+
+struct etsects {
+ struct gianfar_ptp_registers *regs;
+ int irq[N_IRQS];
+ u64 alarm_interval; /* for periodic alarm */
+ u64 alarm_value;
+ u32 tclk_period; /* nanoseconds */
+ u32 tmr_prsc;
+ u32 tmr_add;
+ u32 cksel;
+ u32 tmr_fiper1;
+ u32 tmr_fiper2;
+};
+
+/* Private globals */
+static struct ptp_clock *gianfar_clock;
+static struct etsects the_clock;
+DEFINE_SPINLOCK(register_lock);
+
+/*
+ * Register access functions
+ */
+
+static u64 tmr_cnt_read(struct etsects *etsects)
+{
+ u64 ns;
+ u32 lo, hi;
+
+ lo = gfar_read(&etsects->regs->tmr_cnt_l);
+ hi = gfar_read(&etsects->regs->tmr_cnt_h);
+ ns = ((u64) hi) << 32;
+ ns |= lo;
+ return ns;
+}
+
+static void tmr_cnt_write(struct etsects *etsects, u64 ns)
+{
+ u32 hi = ns >> 32;
+ u32 lo = ns & 0xffffffff;
+
+ gfar_write(&etsects->regs->tmr_cnt_l, lo);
+ gfar_write(&etsects->regs->tmr_cnt_h, hi);
+}
+
+static void set_alarm(struct etsects *etsects)
+{
+ u64 ns;
+ u32 lo, hi;
+
+ ns = tmr_cnt_read(etsects) + 1500000000ULL;
+ ns = div_u64(ns, 1000000000UL) * 1000000000ULL;
+ ns -= etsects->tclk_period;
+ hi = ns >> 32;
+ lo = ns & 0xffffffff;
+ gfar_write(&etsects->regs->tmr_alarm1_l, lo);
+ gfar_write(&etsects->regs->tmr_alarm1_h, hi);
+}
+
+static void set_fipers(struct etsects *etsects)
+{
+ u32 tmr_ctrl = gfar_read(&etsects->regs->tmr_ctrl);
+
+ gfar_write(&etsects->regs->tmr_ctrl, tmr_ctrl & (~TE));
+ gfar_write(&etsects->regs->tmr_prsc, etsects->tmr_prsc);
+ gfar_write(&etsects->regs->tmr_fiper1, etsects->tmr_fiper1);
+ gfar_write(&etsects->regs->tmr_fiper2, etsects->tmr_fiper2);
+ set_alarm(etsects);
+ gfar_write(&etsects->regs->tmr_ctrl, tmr_ctrl|TE);
+}
+
+/*
+ * Interrupt service routine
+ */
+
+static irqreturn_t isr(int irq, void *priv)
+{
+ struct etsects *etsects = priv;
+ struct ptp_clock_event event;
+ u64 ns;
+ u32 ack=0, lo, hi, mask, val;
+
+ val = gfar_read(&etsects->regs->tmr_tevent);
+
+ if (val & ETS1) {
+ ack |= ETS1;
+ hi = gfar_read(&etsects->regs->tmr_etts1_h);
+ lo = gfar_read(&etsects->regs->tmr_etts1_l);
+ event.type = PTP_CLOCK_EXTTS;
+ event.index = 0;
+ event.timestamp = ((u64) hi) << 32;
+ event.timestamp |= lo;
+ ptp_clock_event(gianfar_clock, &event);
+ }
+
+ if (val & ETS2) {
+ ack |= ETS2;
+ hi = gfar_read(&etsects->regs->tmr_etts2_h);
+ lo = gfar_read(&etsects->regs->tmr_etts2_l);
+ event.type = PTP_CLOCK_EXTTS;
+ event.index = 1;
+ event.timestamp = ((u64) hi) << 32;
+ event.timestamp |= lo;
+ ptp_clock_event(gianfar_clock, &event);
+ }
+
+ if (val & ALM2) {
+ ack |= ALM2;
+ if (etsects->alarm_value) {
+ event.type = PTP_CLOCK_ALARM;
+ event.index = 0;
+ event.timestamp = etsects->alarm_value;
+ ptp_clock_event(gianfar_clock, &event);
+ }
+ if (etsects->alarm_interval) {
+ ns = etsects->alarm_value + etsects->alarm_interval;
+ hi = ns >> 32;
+ lo = ns & 0xffffffff;
+ spin_lock(®ister_lock);
+ gfar_write(&etsects->regs->tmr_alarm2_l, lo);
+ gfar_write(&etsects->regs->tmr_alarm2_h, hi);
+ spin_unlock(®ister_lock);
+ etsects->alarm_value = ns;
+ } else {
+ gfar_write(&etsects->regs->tmr_tevent, ALM2);
+ spin_lock(®ister_lock);
+ mask = gfar_read(&etsects->regs->tmr_temask);
+ mask &= ~ALM2EN;
+ gfar_write(&etsects->regs->tmr_temask, mask);
+ spin_unlock(®ister_lock);
+ etsects->alarm_value = 0;
+ etsects->alarm_interval = 0;
+ }
+ }
+
+ gfar_write(&etsects->regs->tmr_tevent, ack);
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * PTP clock operations
+ */
+
+static int ptp_gianfar_adjfreq(void *priv, s32 ppb)
+{
+ u64 adj;
+ u32 diff, tmr_add;
+ int neg_adj = 0;
+ struct etsects *etsects = priv;
+
+ if (!ppb)
+ return 0;
+
+ if (ppb < 0) {
+ neg_adj = 1;
+ ppb = -ppb;
+ }
+ tmr_add = etsects->tmr_add;
+ adj = tmr_add;
+ adj *= ppb;
+ diff = div_u64(adj, 1000000000ULL);
+
+ tmr_add = neg_adj ? tmr_add - diff : tmr_add + diff;
+
+ gfar_write(&etsects->regs->tmr_add, tmr_add);
+
+ return 0;
+}
+
+static int ptp_gianfar_adjtime(void *priv, struct timespec *ts)
+{
+ s64 delta, now;
+ unsigned long flags;
+ struct etsects *etsects = priv;
+
+ delta = 1000000000LL * ts->tv_sec;
+ delta += ts->tv_nsec;
+
+ spin_lock_irqsave(®ister_lock, flags);
+
+ now = tmr_cnt_read(etsects);
+ now += delta;
+ tmr_cnt_write(etsects, now);
+
+ spin_unlock_irqrestore(®ister_lock, flags);
+
+ set_fipers(etsects);
+
+ return 0;
+}
+
+static int ptp_gianfar_gettime(void *priv, struct timespec *ts)
+{
+ u64 ns;
+ u32 remainder;
+ unsigned long flags;
+ struct etsects *etsects = priv;
+
+ spin_lock_irqsave(®ister_lock, flags);
+
+ ns = tmr_cnt_read(etsects);
+
+ spin_unlock_irqrestore(®ister_lock, flags);
+
+ ts->tv_sec = div_u64_rem(ns, 1000000000, &remainder);
+ ts->tv_nsec = remainder;
+ return 0;
+}
+
+static int ptp_gianfar_settime(void *priv, struct timespec *ts)
+{
+ u64 ns;
+ unsigned long flags;
+ struct etsects *etsects = priv;
+
+ ns = ts->tv_sec * 1000000000ULL;
+ ns += ts->tv_nsec;
+
+ spin_lock_irqsave(®ister_lock, flags);
+
+ tmr_cnt_write(etsects, ns);
+ set_fipers(etsects);
+
+ spin_unlock_irqrestore(®ister_lock, flags);
+
+ return 0;
+}
+
+static int ptp_gianfar_gettimer(void *priv, int index, struct itimerspec *ts)
+{
+ u64 now, ns;
+ u32 remainder;
+ unsigned long flags;
+ struct etsects *etsects = priv;
+
+ ns = etsects->alarm_interval;
+
+ ts->it_interval.tv_sec = div_u64_rem(ns, 1000000000, &remainder);
+ ts->it_interval.tv_nsec = remainder;
+
+ spin_lock_irqsave(®ister_lock, flags);
+ now = tmr_cnt_read(etsects);
+ spin_unlock_irqrestore(®ister_lock, flags);
+
+ ns = etsects->alarm_value - now;
+
+ ts->it_value.tv_sec = div_u64_rem(ns, 1000000000, &remainder);
+ ts->it_value.tv_nsec = remainder;
+
+ return 0;
+}
+
+static int ptp_gianfar_settimer(void *p, int i, int abs, struct itimerspec *ts)
+{
+ u64 ns;
+ u32 lo, hi, mask;
+ unsigned long flags;
+ struct etsects *etsects = p;
+
+ ns = ts->it_interval.tv_sec * 1000000000ULL;
+ ns += ts->it_interval.tv_nsec;
+
+ etsects->alarm_interval = ns;
+
+ ns = ts->it_value.tv_sec * 1000000000ULL;
+ ns += ts->it_value.tv_nsec;
+
+ if (!ns) {
+ /* Cancel the timer. */
+ etsects->alarm_value = 0;
+ etsects->alarm_interval = 0;
+ return 0;
+ }
+
+ if (!abs) {
+ spin_lock_irqsave(®ister_lock, flags);
+ ns += tmr_cnt_read(etsects);
+ spin_unlock_irqrestore(®ister_lock, flags);
+ }
+
+ etsects->alarm_value = ns;
+
+ hi = ns >> 32;
+ lo = ns & 0xffffffff;
+
+ spin_lock_irqsave(®ister_lock, flags);
+
+ gfar_write(&etsects->regs->tmr_alarm2_l, lo);
+ gfar_write(&etsects->regs->tmr_alarm2_h, hi);
+
+ mask = gfar_read(&etsects->regs->tmr_temask);
+ mask |= ALM2EN;
+ gfar_write(&etsects->regs->tmr_temask, mask);
+
+ spin_unlock_irqrestore(®ister_lock, flags);
+
+ return 0;
+}
+
+static int ptp_gianfar_enable(void *priv, struct ptp_clock_request *rq, int on)
+{
+ struct etsects *etsects = priv;
+ unsigned long flags;
+ u32 bit, mask;
+
+ switch (rq->type) {
+ case PTP_REQUEST_EXTTS:
+ switch (rq->index) {
+ case 0:
+ bit = ETS1EN;
+ break;
+ case 1:
+ bit = ETS2EN;
+ break;
+ default:
+ return -EINVAL;
+ }
+ spin_lock_irqsave(®ister_lock, flags);
+ if (on) {
+ mask = gfar_read(&etsects->regs->tmr_temask);
+ mask |= bit;
+ gfar_write(&etsects->regs->tmr_temask, mask);
+ } else {
+ mask = gfar_read(&etsects->regs->tmr_temask);
+ mask &= ~bit;
+ gfar_write(&etsects->regs->tmr_temask, mask);
+ }
+ spin_unlock_irqrestore(®ister_lock, flags);
+ return 0;
+ }
+
+ return -EOPNOTSUPP;
+}
+
+static struct ptp_clock_info ptp_gianfar_caps = {
+ .owner = THIS_MODULE,
+ .name = "gianfar clock",
+ .max_adj = 512000,
+ .n_alarm = N_ALARM,
+ .n_ext_ts = N_EXT_TS,
+ .n_per_out = 0,
+ .pps = 0,
+ .priv = &the_clock,
+ .adjfreq = ptp_gianfar_adjfreq,
+ .adjtime = ptp_gianfar_adjtime,
+ .gettime = ptp_gianfar_gettime,
+ .settime = ptp_gianfar_settime,
+ .gettimer = ptp_gianfar_gettimer,
+ .settimer = ptp_gianfar_settimer,
+ .enable = ptp_gianfar_enable,
+};
+
+/* OF device tree */
+
+static int get_of_u32(struct device_node *node, char *str, u32 *val)
+{
+ int plen;
+ const u32 *prop = of_get_property(node, str, &plen);
+
+ if (!prop || plen != sizeof(*prop))
+ return -1;
+ *val = *prop;
+ return 0;
+}
+
+static int gianfar_ptp_probe(struct of_device* dev,
+ const struct of_device_id *match)
+{
+ u64 addr, size;
+ struct device_node *node = dev->node;
+ struct etsects *etsects = &the_clock;
+ struct timespec now;
+ phys_addr_t reg_addr;
+ unsigned long reg_size;
+ u32 tmr_ctrl;
+ int i;
+
+ if (get_of_u32(node, "tclk_period", &etsects->tclk_period) ||
+ get_of_u32(node, "tmr_prsc", &etsects->tmr_prsc) ||
+ get_of_u32(node, "tmr_add", &etsects->tmr_add) ||
+ get_of_u32(node, "cksel", &etsects->cksel) ||
+ get_of_u32(node, "tmr_fiper1", &etsects->tmr_fiper1) ||
+ get_of_u32(node, "tmr_fiper2", &etsects->tmr_fiper2))
+ return -ENODEV;
+
+ for (i = 0; i < N_IRQS; i++) {
+
+ etsects->irq[i] = irq_of_parse_and_map(node, i);
+
+ if (etsects->irq[i] == NO_IRQ) {
+ pr_err("irq[%d] not in device tree", i);
+ return -ENODEV;
+ }
+
+ if (request_irq(etsects->irq[i], isr, 0, DRIVER, etsects)) {
+ pr_err("request_irq failed irq %d", etsects->irq[i]);
+ return -ENODEV;
+ }
+ }
+
+ addr = of_translate_address(node, of_get_address(node, 0, &size, NULL));
+ reg_addr = addr;
+ reg_size = size;
+ if (reg_size < REG_SIZE) {
+ pr_warning("device tree reg range %lu too small\n", reg_size);
+ reg_size = REG_SIZE;
+ }
+ etsects->regs = ioremap(reg_addr, reg_size);
+ if (!etsects->regs) {
+ pr_err("ioremap ptp registers failed\n");
+ return -EINVAL;
+ }
+
+ tmr_ctrl =
+ (etsects->tclk_period & TCLK_PERIOD_MASK) << TCLK_PERIOD_SHIFT |
+ (etsects->cksel & CKSEL_MASK) << CKSEL_SHIFT;
+
+ getnstimeofday(&now);
+ ptp_gianfar_settime(etsects, &now);
+
+ gfar_write(&etsects->regs->tmr_ctrl, tmr_ctrl);
+ gfar_write(&etsects->regs->tmr_add, etsects->tmr_add);
+ gfar_write(&etsects->regs->tmr_prsc, etsects->tmr_prsc);
+ gfar_write(&etsects->regs->tmr_fiper1, etsects->tmr_fiper1);
+ gfar_write(&etsects->regs->tmr_fiper2, etsects->tmr_fiper2);
+ set_alarm(etsects);
+ gfar_write(&etsects->regs->tmr_ctrl, tmr_ctrl|FS|RTPE|TE);
+
+ gianfar_clock = ptp_clock_register(&ptp_gianfar_caps);
+
+ return IS_ERR(gianfar_clock) ? PTR_ERR(gianfar_clock) : 0;
+}
+
+static int gianfar_ptp_remove(struct of_device* dev)
+{
+ int i;
+
+ gfar_write(&the_clock.regs->tmr_temask, 0);
+ gfar_write(&the_clock.regs->tmr_ctrl, 0);
+
+ ptp_clock_unregister(gianfar_clock);
+
+ for (i = 0; i < N_IRQS; i++)
+ free_irq(the_clock.irq[i], &the_clock);
+
+ iounmap(the_clock.regs);
+
+ return 0;
+}
+
+static struct of_device_id match_table[] = {
+ { .type = "ptp_clock" },
+ {},
+};
+
+static struct of_platform_driver gianfar_ptp_driver = {
+ .name = "gianfar_ptp",
+ .match_table = match_table,
+ .owner = THIS_MODULE,
+ .probe = gianfar_ptp_probe,
+ .remove = gianfar_ptp_remove,
+};
+
+/* module operations */
+
+static void __exit ptp_gianfar_exit(void)
+{
+ of_unregister_platform_driver(&gianfar_ptp_driver);
+}
+
+static int __init ptp_gianfar_init(void)
+{
+ return of_register_platform_driver(&gianfar_ptp_driver);
+}
+
+module_init(ptp_gianfar_init);
+module_exit(ptp_gianfar_exit);
+
+MODULE_AUTHOR("Richard Cochran <richard.cochran@omicron.at>");
+MODULE_DESCRIPTION("PTP clock using the eTSEC");
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/gianfar_ptp_reg.h b/drivers/net/gianfar_ptp_reg.h
new file mode 100644
index 0000000..6e2b82f
--- /dev/null
+++ b/drivers/net/gianfar_ptp_reg.h
@@ -0,0 +1,113 @@
+/* gianfar_ptp_reg.h
+ * Generated by regen.tcl on Thu May 13 01:38:57 PM CEST 2010
+ *
+ * PTP 1588 clock using the gianfar eTSEC
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#ifndef _GIANFAR_PTP_REG_H_
+#define _GIANFAR_PTP_REG_H_
+
+struct gianfar_ptp_registers {
+ u32 tmr_ctrl; /* Timer control register */
+ u32 tmr_tevent; /* Timestamp event register */
+ u32 tmr_temask; /* Timer event mask register */
+ u32 tmr_pevent; /* Timestamp event register */
+ u32 tmr_pemask; /* Timer event mask register */
+ u32 tmr_stat; /* Timestamp status register */
+ u32 tmr_cnt_h; /* Timer counter high register */
+ u32 tmr_cnt_l; /* Timer counter low register */
+ u32 tmr_add; /* Timer drift compensation addend register */
+ u32 tmr_acc; /* Timer accumulator register */
+ u32 tmr_prsc; /* Timer prescale */
+ u8 res1[4];
+ u32 tmroff_h; /* Timer offset high */
+ u32 tmroff_l; /* Timer offset low */
+ u8 res2[8];
+ u32 tmr_alarm1_h; /* Timer alarm 1 high register */
+ u32 tmr_alarm1_l; /* Timer alarm 1 high register */
+ u32 tmr_alarm2_h; /* Timer alarm 2 high register */
+ u32 tmr_alarm2_l; /* Timer alarm 2 high register */
+ u8 res3[48];
+ u32 tmr_fiper1; /* Timer fixed period interval */
+ u32 tmr_fiper2; /* Timer fixed period interval */
+ u32 tmr_fiper3; /* Timer fixed period interval */
+ u8 res4[20];
+ u32 tmr_etts1_h; /* Timestamp of general purpose external trigger */
+ u32 tmr_etts1_l; /* Timestamp of general purpose external trigger */
+ u32 tmr_etts2_h; /* Timestamp of general purpose external trigger */
+ u32 tmr_etts2_l; /* Timestamp of general purpose external trigger */
+};
+
+/* Bit definitions for the TMR_CTRL register */
+#define ALM1P (1<<31) /* Alarm1 output polarity */
+#define ALM2P (1<<30) /* Alarm2 output polarity */
+#define FS (1<<28) /* FIPER start indication */
+#define PP1L (1<<27) /* Fiper1 pulse loopback mode enabled. */
+#define PP2L (1<<26) /* Fiper2 pulse loopback mode enabled. */
+#define TCLK_PERIOD_SHIFT (16) /* 1588 timer reference clock period. */
+#define TCLK_PERIOD_MASK (0x3ff)
+#define RTPE (1<<15) /* Record Tx Timestamp to PAL Enable. */
+#define FRD (1<<14) /* FIPER Realignment Disable */
+#define ESFDP (1<<11) /* External Tx/Rx SFD Polarity. */
+#define ESFDE (1<<10) /* External Tx/Rx SFD Enable. */
+#define ETEP2 (1<<9) /* External trigger 2 edge polarity */
+#define ETEP1 (1<<8) /* External trigger 1 edge polarity */
+#define COPH (1<<7) /* Generated clock (TSEC_1588_GCLK) output phase. */
+#define CIPH (1<<6) /* External oscillator input clock phase. */
+#define TMSR (1<<5) /* Timer soft reset. When enabled, it resets all the timer registers and state machines. */
+#define BYP (1<<3) /* Bypass drift compensated clock */
+#define TE (1<<2) /* 1588 timer enable. If not enabled, all the timer registers and state machines are disabled. */
+#define CKSEL_SHIFT (0) /* 1588 Timer reference clock source select. */
+#define CKSEL_MASK (0x3)
+
+/* Bit definitions for the TMR_TEVENT register */
+#define ETS2 (1<<25) /* External trigger 2 timestamp sampled */
+#define ETS1 (1<<24) /* External trigger 1 timestamp sampled */
+#define ALM2 (1<<17) /* Current time equaled alarm time register 2 */
+#define ALM1 (1<<16) /* Current time equaled alarm time register 1 */
+#define PP1 (1<<7) /* Indicates that a periodic pulse has been generated based on FIPER1 register */
+#define PP2 (1<<6) /* Indicates that a periodic pulse has been generated based on FIPER2 register */
+#define PP3 (1<<5) /* Indicates that a periodic pulse has been generated based on FIPER3 register */
+
+/* Bit definitions for the TMR_TEMASK register */
+#define ETS2EN (1<<25) /* External trigger 2 timestamp sample event enable */
+#define ETS1EN (1<<24) /* External trigger 1 timestamp sample event enable */
+#define ALM2EN (1<<17) /* Timer ALM2 event enable */
+#define ALM1EN (1<<16) /* Timer ALM1 event enable */
+#define PP1EN (1<<7) /* Periodic pulse event 1 enable */
+#define PP2EN (1<<6) /* Periodic pulse event 2 enable */
+
+/* Bit definitions for the TMR_PEVENT register */
+#define TXP2 (1<<9) /* Indicates that a PTP frame has been transmitted and its timestamp is stored in TXTS2 register */
+#define TXP1 (1<<8) /* Indicates that a PTP frame has been transmitted and its timestamp is stored in TXTS1 register */
+#define RXP (1<<0) /* Indicates that a PTP frame has been received */
+
+/* Bit definitions for the TMR_PEMASK register */
+#define TXP2EN (1<<9) /* Transmit PTP packet event 2 enable */
+#define TXP1EN (1<<8) /* Transmit PTP packet event 1 enable */
+#define RXPEN (1<<0) /* Receive PTP packet event enable */
+
+/* Bit definitions for the TMR_STAT register */
+#define STAT_VEC_SHIFT (0) /* Timer general purpose status vector */
+#define STAT_VEC_MASK (0x3f)
+
+/* Bit definitions for the TMR_PRSC register */
+#define PRSC_OCK_SHIFT (0) /* Output clock division/prescale factor. */
+#define PRSC_OCK_MASK (0xffff)
+
+#endif
diff --git a/drivers/ptp/Kconfig b/drivers/ptp/Kconfig
index 9390d44..3b7bd73 100644
--- a/drivers/ptp/Kconfig
+++ b/drivers/ptp/Kconfig
@@ -35,4 +35,17 @@ config PTP_1588_CLOCK_LINUX
To compile this driver as a module, choose M here: the module
will be called ptp_linux.
+config PTP_1588_CLOCK_GIANFAR
+ tristate "Freescale eTSEC as PTP clock"
+ depends on PTP_1588_CLOCK
+ depends on GIANFAR
+ help
+ This driver adds support for using the eTSEC as a PTP
+ clock. This clock is only useful if your PTP programs are
+ getting hardware time stamps on the PTP Ethernet packets
+ using the SO_TIMESTAMPING API.
+
+ To compile this driver as a module, choose M here: the module
+ will be called gianfar_ptp.
+
endmenu
--
1.6.3.3
^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [PATCH v3 3/3] ptp: Added a clock that uses the eTSEC found on the MPC85xx.
2010-05-14 16:46 ` [PATCH v3 3/3] ptp: Added a clock that uses the eTSEC found on the MPC85xx Richard Cochran
@ 2010-05-14 17:46 ` Scott Wood
[not found] ` <4BED8C91.8020107-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
2010-05-17 15:41 ` Wolfgang Grandegger
1 sibling, 1 reply; 11+ messages in thread
From: Scott Wood @ 2010-05-14 17:46 UTC (permalink / raw)
To: Richard Cochran; +Cc: netdev, devicetree-discuss, linuxppc-dev
On 05/14/2010 11:46 AM, Richard Cochran wrote:
> diff --git a/Documentation/powerpc/dts-bindings/fsl/tsec.txt b/Documentation/powerpc/dts-bindings/fsl/tsec.txt
> index edb7ae1..b09ba66 100644
> --- a/Documentation/powerpc/dts-bindings/fsl/tsec.txt
> +++ b/Documentation/powerpc/dts-bindings/fsl/tsec.txt
> @@ -74,3 +74,59 @@ Example:
> interrupt-parent =<&mpic>;
> phy-handle =<&phy0>
> };
> +
> +* Gianfar PTP clock nodes
> +
> +General Properties:
> +
> + - device_type Should be "ptp_clock"
Device_type is deprecated in most contexts for flat device trees.
> + - model Model of the device. Must be "eTSEC"
Model, while abused by the current gianfar binding code, is not supposed
to be something that is ordinarily used to bind on. It is supposed to
be a freeform field for indicating the specific model of hardware,
mainly for human consumption or as a last resort for working around
problems.
Get rid of both device_type and model, and specify a compatible string
instead (e.g. "fsl,etsec-ptp"). Or perhaps this should just be some
additional properties on the existing gianfar nodes, rather than
presenting it as a separate device? How do you associate a given ptp
block with the corresponding gianfar node? If there are differences in
ptp implementation between different versions of etsec, can the ptp
driver see the etsec version register?
> + - reg Offset and length of the register set for the device
> + - interrupts There should be at least two and as many as four
> + PTP related interrupts
> +
> +Clock Properties:
> +
> + - tclk_period Timer reference clock period in nanoseconds.
> + - tmr_prsc Prescaler, divides the output clock.
> + - tmr_add Frequency compensation value.
> + - cksel 0= external clock, 1= eTSEC system clock, 3= RTC clock input.
> + Currently the driver only supports choice "1".
> + - tmr_fiper1 Fixed interval period pulse generator.
> + - tmr_fiper2 Fixed interval period pulse generator.
Dashes are more typical in OF names than underscores, and it's generally
better to be a little more verbose -- these aren't local loop iterators.
They should probably have an "fsl,ptp-" prefix as well.
> + These properties set the operational parameters for the PTP
> + clock. You must choose these carefully for the clock to work right.
Do these values describe the way the hardware is, or how it's been
configured by firmware, or a set of values that are clearly optimal for
this particular board? If it's just configuration for the Linux driver,
that could reasonably differ based on what a given user or OS will want,
the device tree probably isn't the right place for it.
> diff --git a/arch/powerpc/boot/dts/p2020ds.dts b/arch/powerpc/boot/dts/p2020ds.dts
> index 1101914..f72353a 100644
> --- a/arch/powerpc/boot/dts/p2020ds.dts
> +++ b/arch/powerpc/boot/dts/p2020ds.dts
> @@ -336,6 +336,20 @@
> phy_type = "ulpi";
> };
>
> + ptp_clock@24E00 {
> + device_type = "ptp_clock";
> + model = "eTSEC";
> + reg = <0x24E00 0xB0>;
> + interrupts = <68 2 69 2 70 2>;
> + interrupt-parent = < &mpic >;
> + tclk_period = <5>;
> + tmr_prsc = <200>;
> + tmr_add = <0xCCCCCCCD>;
> + cksel = <1>;
> + tmr_fiper1 = <0x3B9AC9FB>;
> + tmr_fiper2 = <0x0001869B>;
> + };
> +
This one has 3 interrupts? The driver supports only two.
> +/* Private globals */
> +static struct ptp_clock *gianfar_clock;
Do you not support more than one of these?
> +static struct etsects the_clock;
"The" clock? As oppsed to the "other" clock one line above? :-)
> +static irqreturn_t isr(int irq, void *priv)
> +{
> + struct etsects *etsects = priv;
> + struct ptp_clock_event event;
> + u64 ns;
> + u32 ack=0, lo, hi, mask, val;
> +
> + val = gfar_read(&etsects->regs->tmr_tevent);
> +
> + if (val& ETS1) {
> + ack |= ETS1;
> + hi = gfar_read(&etsects->regs->tmr_etts1_h);
> + lo = gfar_read(&etsects->regs->tmr_etts1_l);
> + event.type = PTP_CLOCK_EXTTS;
> + event.index = 0;
> + event.timestamp = ((u64) hi)<< 32;
> + event.timestamp |= lo;
> + ptp_clock_event(gianfar_clock,&event);
> + }
> +
> + if (val& ETS2) {
> + ack |= ETS2;
> + hi = gfar_read(&etsects->regs->tmr_etts2_h);
> + lo = gfar_read(&etsects->regs->tmr_etts2_l);
> + event.type = PTP_CLOCK_EXTTS;
> + event.index = 1;
> + event.timestamp = ((u64) hi)<< 32;
> + event.timestamp |= lo;
> + ptp_clock_event(gianfar_clock,&event);
> + }
> +
> + if (val& ALM2) {
> + ack |= ALM2;
> + if (etsects->alarm_value) {
> + event.type = PTP_CLOCK_ALARM;
> + event.index = 0;
> + event.timestamp = etsects->alarm_value;
> + ptp_clock_event(gianfar_clock,&event);
> + }
> + if (etsects->alarm_interval) {
> + ns = etsects->alarm_value + etsects->alarm_interval;
> + hi = ns>> 32;
> + lo = ns& 0xffffffff;
> + spin_lock(®ister_lock);
> + gfar_write(&etsects->regs->tmr_alarm2_l, lo);
> + gfar_write(&etsects->regs->tmr_alarm2_h, hi);
> + spin_unlock(®ister_lock);
> + etsects->alarm_value = ns;
> + } else {
> + gfar_write(&etsects->regs->tmr_tevent, ALM2);
> + spin_lock(®ister_lock);
> + mask = gfar_read(&etsects->regs->tmr_temask);
> + mask&= ~ALM2EN;
> + gfar_write(&etsects->regs->tmr_temask, mask);
> + spin_unlock(®ister_lock);
> + etsects->alarm_value = 0;
> + etsects->alarm_interval = 0;
> + }
> + }
> +
> + gfar_write(&etsects->regs->tmr_tevent, ack);
> +
> + return IRQ_HANDLED;
Should only return IRQ_HANDLED if you found an event.
> + if (get_of_u32(node, "tclk_period",&etsects->tclk_period) ||
> + get_of_u32(node, "tmr_prsc",&etsects->tmr_prsc) ||
> + get_of_u32(node, "tmr_add",&etsects->tmr_add) ||
> + get_of_u32(node, "cksel",&etsects->cksel) ||
> + get_of_u32(node, "tmr_fiper1",&etsects->tmr_fiper1) ||
> + get_of_u32(node, "tmr_fiper2",&etsects->tmr_fiper2))
> + return -ENODEV;
Might want to print an error so the user knows what's missing.
> + for (i = 0; i< N_IRQS; i++) {
> +
> + etsects->irq[i] = irq_of_parse_and_map(node, i);
> +
> + if (etsects->irq[i] == NO_IRQ) {
> + pr_err("irq[%d] not in device tree", i);
> + return -ENODEV;
> + }
> +
> + if (request_irq(etsects->irq[i], isr, 0, DRIVER, etsects)) {
> + pr_err("request_irq failed irq %d", etsects->irq[i]);
> + return -ENODEV;
> + }
You've got two IRQs, with the same handler, and the same dev_id? From
the manual it looks like there's one PTP interrupt per eTSEC (which
would explain 3 interrupts on p2020).
> +static struct of_device_id match_table[] = {
> + { .type = "ptp_clock" },
> + {},
> +};
This driver controls every possible PTP implementation?
-Scott
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v3 3/3] ptp: Added a clock that uses the eTSEC found on the MPC85xx.
[not found] ` <4BED8C91.8020107-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
@ 2010-05-17 8:27 ` Richard Cochran
2010-05-17 18:05 ` Scott Wood
0 siblings, 1 reply; 11+ messages in thread
From: Richard Cochran @ 2010-05-17 8:27 UTC (permalink / raw)
To: Scott Wood
Cc: netdev-u79uwXL29TY76Z2rM5mHXA,
devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ,
linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ
On Fri, May 14, 2010 at 12:46:57PM -0500, Scott Wood wrote:
> On 05/14/2010 11:46 AM, Richard Cochran wrote:
> >diff --git a/Documentation/powerpc/dts-bindings/fsl/tsec.txt b/Documentation/powerpc/dts-bindings/fsl/tsec.txt
>
> Get rid of both device_type and model, and specify a compatible
> string instead (e.g. "fsl,etsec-ptp").
Okay, will do. I really am at a loss at understanding all the rules in
the whole device tree world. I just tried to follow
Documentation/powerpc and what is already present in the kernel.
> Or perhaps this should just be some additional properties on the
> existing gianfar nodes, rather than presenting it as a separate
> device? How do you associate a given ptp block with the
> corresponding gianfar node?
There only one PTP clock. Its registers repeat in each port's memory
space, but you are only supposed to touch the first set of PTP
registers. If you consider how PTP works, there can never be per port
clocks, since this would make it impossible to make a boundary clock,
for example.
The whole idea of this PTP clock framework is to keep the clock
drivers separate from the MAC drivers, even when they use the same
hardware. The functionality is logically divided into two parts. The
MAC provides time stamps, and the clock provides a way to control its
offset and frequency.
Up until this point, people have simply hacked new private ioctls into
the driver for each MAC that supports PTP. That is not a good long
term solution for PTP support in Linux.
In general, I think it will not be hard to keep the MAC and the clock
drivers from stepping on each other's toes. The eTSEC hardware is
certainly able to be used in this way.
> If there are differences in ptp implementation between different
> versions of etsec, can the ptp driver see the etsec version
> register?
There are no differences (that I know of) in how the PTP clocks
work. I have in house the mpc8313, the mpc8572, and the p2020. The
mpc8572 appears to lack some of the TMR_CTRL bits, but this is
probably a documentation bug. I will check it.
> >+ - tclk_period Timer reference clock period in nanoseconds.
> >+ - tmr_prsc Prescaler, divides the output clock.
> >+ - tmr_add Frequency compensation value.
> >+ - cksel 0= external clock, 1= eTSEC system clock, 3= RTC clock input.
> >+ Currently the driver only supports choice "1".
> >+ - tmr_fiper1 Fixed interval period pulse generator.
> >+ - tmr_fiper2 Fixed interval period pulse generator.
>
> Dashes are more typical in OF names than underscores, and it's
> generally better to be a little more verbose -- these aren't local
> loop iterators.
The names come from the register mnemonics from the documentation. I
prefer to use the same names as is found in the manuals. That way, a
person working with docu in hand will have an easier job.
> They should probably have an "fsl,ptp-" prefix as well.
Okay, but must I then change the following code in order to find them?
Does adding the prefix just mean that I also add it to my search
strings, or is it preprocessed (stripped) somehow?
static int get_of_u32(struct device_node *node, char *str, u32 *val)
{
int plen;
const u32 *prop = of_get_property(node, str, &plen);
if (!prop || plen != sizeof(*prop))
return -1;
*val = *prop;
return 0;
}
...
if (get_of_u32(node, "tclk_period",&etsects->tclk_period) ||
get_of_u32(node, "tmr_prsc",&etsects->tmr_prsc) ||
get_of_u32(node, "tmr_add",&etsects->tmr_add) ||
get_of_u32(node, "cksel",&etsects->cksel) ||
get_of_u32(node, "tmr_fiper1",&etsects->tmr_fiper1) ||
get_of_u32(node, "tmr_fiper2",&etsects->tmr_fiper2))
return -ENODEV;
> >+ These properties set the operational parameters for the PTP
> >+ clock. You must choose these carefully for the clock to work right.
>
> Do these values describe the way the hardware is, or how it's been
> configured by firmware, or a set of values that are clearly optimal
> for this particular board? If it's just configuration for the Linux
> driver, that could reasonably differ based on what a given user or
> OS will want, the device tree probably isn't the right place for it.
The values are related to the board. One important parameter is the
input clock, and the rest reflect some engineering decisions/tradeoffs
related to the signals to and from the PTP clock. There is not just
one "optimal" choice, so I wanted to let the designer set the
values. In any case, the parameters are definitely related to the
board (not to the cpu or to linux), so I think the device tree is the
right place for them.
> This one has 3 interrupts? The driver supports only two.
The documentation does not specify the IRQ line that each event
belongs to. After some trial and error, it appears that all of the
ancillary clock interrupts arrive on the first interrupt. The other
lines (one per port) must be for the Tx/Rx packet time stamp
indication, but we don't need these for the clock or for the MAC.
I'll just reduce the driver to one interrupt.
> >+/* Private globals */
> >+static struct ptp_clock *gianfar_clock;
>
> Do you not support more than one of these?
>
> >+static struct etsects the_clock;
>
> "The" clock? As oppsed to the "other" clock one line above? :-)
The 'gianfar_clock' variable holds the returned instance from the
class driver, while 'the_clock' is the driver's private data (and
there can only be one driver).
I'll combine these into one struct to make it more clear and less
funny sounding.
> >+ return IRQ_HANDLED;
>
> Should only return IRQ_HANDLED if you found an event.
Okay.
> >+ if (get_of_u32(node, "tclk_period",&etsects->tclk_period) ||
> >+ get_of_u32(node, "tmr_prsc",&etsects->tmr_prsc) ||
> >+ get_of_u32(node, "tmr_add",&etsects->tmr_add) ||
> >+ get_of_u32(node, "cksel",&etsects->cksel) ||
> >+ get_of_u32(node, "tmr_fiper1",&etsects->tmr_fiper1) ||
> >+ get_of_u32(node, "tmr_fiper2",&etsects->tmr_fiper2))
> >+ return -ENODEV;
>
> Might want to print an error so the user knows what's missing.
Okay.
> You've got two IRQs, with the same handler, and the same dev_id?
> From the manual it looks like there's one PTP interrupt per eTSEC
> (which would explain 3 interrupts on p2020).
Will reduce to just one IRQ.
> >+static struct of_device_id match_table[] = {
> >+ { .type = "ptp_clock" },
> >+ {},
> >+};
>
> This driver controls every possible PTP implementation?
No, I only want to match with the eTSEC clock device. Given the
compatible string above ("fsl,etsec-ptp"), what is the correct way to
do this? (pointer to an existing driver to emulate would be enough)
Thanks for your help,
Richard
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v3 1/3] ptp: Added a brand new class driver for ptp clocks.
2010-05-14 16:45 ` [PATCH v3 1/3] ptp: Added a brand new class driver for ptp clocks Richard Cochran
@ 2010-05-17 15:41 ` Wolfgang Grandegger
0 siblings, 0 replies; 11+ messages in thread
From: Wolfgang Grandegger @ 2010-05-17 15:41 UTC (permalink / raw)
To: Richard Cochran; +Cc: netdev, linuxppc-dev, devicetree-discuss
On 05/14/2010 06:45 PM, Richard Cochran wrote:
> This patch adds an infrastructure for hardware clocks that implement
> IEEE 1588, the Precision Time Protocol (PTP). A class driver offers a
> registration method to particular hardware clock drivers. Each clock is
> exposed to user space as a character device with ioctls that allow tuning
> of the PTP clock.
>
> Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Tested-by: Wolfgang Grandegger <wg@denx.de>
on my Freescale MPC8313 setup with ptpd and ptpv2d.
Wolfgang.
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v3 3/3] ptp: Added a clock that uses the eTSEC found on the MPC85xx.
2010-05-14 16:46 ` [PATCH v3 3/3] ptp: Added a clock that uses the eTSEC found on the MPC85xx Richard Cochran
2010-05-14 17:46 ` Scott Wood
@ 2010-05-17 15:41 ` Wolfgang Grandegger
1 sibling, 0 replies; 11+ messages in thread
From: Wolfgang Grandegger @ 2010-05-17 15:41 UTC (permalink / raw)
To: Richard Cochran; +Cc: netdev, linuxppc-dev, devicetree-discuss
On 05/14/2010 06:46 PM, Richard Cochran wrote:
> The eTSEC includes a PTP clock with quite a few features. This patch adds
> support for the basic clock adjustment functions, plus two external time
> stamps and one alarm.
>
> Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Tested-by: Wolfgang Grandegger <wg@denx.de>
on my Freescale MPC8313 setup with ptpd and ptpv2d.
FYI: checkplatch.pl reports various errors for this patch series.
Wolfgang.
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v3 3/3] ptp: Added a clock that uses the eTSEC found on the MPC85xx.
2010-05-17 8:27 ` Richard Cochran
@ 2010-05-17 18:05 ` Scott Wood
[not found] ` <4BF18582.6000500-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
0 siblings, 1 reply; 11+ messages in thread
From: Scott Wood @ 2010-05-17 18:05 UTC (permalink / raw)
To: Richard Cochran; +Cc: netdev, devicetree-discuss, linuxppc-dev
On 05/17/2010 03:27 AM, Richard Cochran wrote:
> On Fri, May 14, 2010 at 12:46:57PM -0500, Scott Wood wrote:
>> On 05/14/2010 11:46 AM, Richard Cochran wrote:
>>> diff --git a/Documentation/powerpc/dts-bindings/fsl/tsec.txt b/Documentation/powerpc/dts-bindings/fsl/tsec.txt
>>
>> Get rid of both device_type and model, and specify a compatible
>> string instead (e.g. "fsl,etsec-ptp").
>
> Okay, will do. I really am at a loss at understanding all the rules in
> the whole device tree world. I just tried to follow
> Documentation/powerpc and what is already present in the kernel.
There's some stuff in there that isn't how we'd do it now, but is slow
to change for compatibility reasons.
>> Or perhaps this should just be some additional properties on the
>> existing gianfar nodes, rather than presenting it as a separate
>> device? How do you associate a given ptp block with the
>> corresponding gianfar node?
>
> There only one PTP clock. Its registers repeat in each port's memory
> space, but you are only supposed to touch the first set of PTP
> registers.
OK. I'm not too familiar with PTP itself, was looking more at the
device tree and similar structural bits.
> There are no differences (that I know of) in how the PTP clocks
> work. I have in house the mpc8313, the mpc8572, and the p2020. The
> mpc8572 appears to lack some of the TMR_CTRL bits, but this is
> probably a documentation bug. I will check it.
If there's any possibility of needing to make a distinction (which
probably can't be ruled out with future chips), the chip name could be
made part of the compatible string, with a secondary compatible showing
a canonical part name for that version of the PTP block. E.g. p2020
might have:
compatble = "fsl,p2020-etsec-ptp", "fsl,mpc8313-etsec-ptp";
The driver would bind only on the mpc8313 version.
There are several examples of this, such as the Freescale i2c driver and
binding (ignore the legacy "fsl-i2c").
>> > >+ - tmr_fiper1 Fixed interval period pulse generator.
>> > >+ - tmr_fiper2 Fixed interval period pulse generator.
>>
MPC8572 and P2020 have fiper3 as well.
>> They should probably have an "fsl,ptp-" prefix as well.
>
> Okay, but must I then change the following code in order to find them?
> Does adding the prefix just mean that I also add it to my search
> strings, or is it preprocessed (stripped) somehow?
It is not stripped; you have to change the code as well.
>> You've got two IRQs, with the same handler, and the same dev_id?
>> From the manual it looks like there's one PTP interrupt per eTSEC
>> (which would explain 3 interrupts on p2020).
>
> Will reduce to just one IRQ.
The device tree should still contain all of the interrupts, in case
they're needed later -- and put a comment in the driver saying why the
first interrupt seems sufficient.
>>> +static struct of_device_id match_table[] = {
>>> + { .type = "ptp_clock" },
>>> + {},
>>> +};
>>
>> This driver controls every possible PTP implementation?
>
> No, I only want to match with the eTSEC clock device. Given the
> compatible string above ("fsl,etsec-ptp"), what is the correct way to
> do this? (pointer to an existing driver to emulate would be enough)
Put .compatible = "fsl,etsec-ptp" (or "fsl,mpc8313-etsec-ptp") where you
have .type = "ptp_clock".
-Scott
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v3 3/3] ptp: Added a clock that uses the eTSEC found on the MPC85xx.
[not found] ` <4BF18582.6000500-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
@ 2010-05-18 6:36 ` Richard Cochran
2010-05-18 16:23 ` Scott Wood
0 siblings, 1 reply; 11+ messages in thread
From: Richard Cochran @ 2010-05-18 6:36 UTC (permalink / raw)
To: Scott Wood
Cc: netdev-u79uwXL29TY76Z2rM5mHXA,
devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ,
linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ
On Mon, May 17, 2010 at 01:05:54PM -0500, Scott Wood wrote:
> >>> >+ - tmr_fiper1 Fixed interval period pulse generator.
> >>> >+ - tmr_fiper2 Fixed interval period pulse generator.
> >>
>
> MPC8572 and P2020 have fiper3 as well.
I doubt they really have a third fiper.
First of all, this signal is not routed anywhere on the boards. Also,
according to the documentation, it has no bit in the TMR_CTRL or the
TMR_TEMASK registers. Unless there is a bit in TMR_TEMASK, you cannot
get an interrupt from it.
If you cannot use the signal externally (in the "real" world) and you
cannot get an interrupt, what good is it to have such a periodic
signal? Polling the bit in the TMR_TEVENT to see when a pulse occurs
seems pointless.
Scott, you have connections, right? Can you clarify this for me?
Thanks,
Richard
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v3 3/3] ptp: Added a clock that uses the eTSEC found on the MPC85xx.
2010-05-18 6:36 ` Richard Cochran
@ 2010-05-18 16:23 ` Scott Wood
0 siblings, 0 replies; 11+ messages in thread
From: Scott Wood @ 2010-05-18 16:23 UTC (permalink / raw)
To: Richard Cochran; +Cc: netdev, devicetree-discuss, linuxppc-dev
On 05/18/2010 01:36 AM, Richard Cochran wrote:
> On Mon, May 17, 2010 at 01:05:54PM -0500, Scott Wood wrote:
>>>>>> + - tmr_fiper1 Fixed interval period pulse generator.
>>>>>> + - tmr_fiper2 Fixed interval period pulse generator.
>>>>
>>
>> MPC8572 and P2020 have fiper3 as well.
>
> I doubt they really have a third fiper.
>
> First of all, this signal is not routed anywhere on the boards.
OK, but that's a separate issue from whether it exists on the chip and
could be used on a different board.
> Also, according to the documentation, it has no bit in the TMR_CTRL or the
> TMR_TEMASK registers.
It does seem inconsistent -- but could just be bad docs.
> Unless there is a bit in TMR_TEMASK, you cannot
> get an interrupt from it.
>
> If you cannot use the signal externally (in the "real" world) and you
> cannot get an interrupt, what good is it to have such a periodic
> signal? Polling the bit in the TMR_TEVENT to see when a pulse occurs
> seems pointless.
>
> Scott, you have connections, right? Can you clarify this for me?
I'll ask around.
-Scott
^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2010-05-18 16:23 UTC | newest]
Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2010-05-14 16:44 [PATCH v3 0/3] ptp: IEEE 1588 clock support Richard Cochran
2010-05-14 16:45 ` [PATCH v3 1/3] ptp: Added a brand new class driver for ptp clocks Richard Cochran
2010-05-17 15:41 ` Wolfgang Grandegger
2010-05-14 16:46 ` [PATCH v3 2/3] ptp: Added a clock that uses the Linux system time Richard Cochran
2010-05-14 16:46 ` [PATCH v3 3/3] ptp: Added a clock that uses the eTSEC found on the MPC85xx Richard Cochran
2010-05-14 17:46 ` Scott Wood
[not found] ` <4BED8C91.8020107-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
2010-05-17 8:27 ` Richard Cochran
2010-05-17 18:05 ` Scott Wood
[not found] ` <4BF18582.6000500-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
2010-05-18 6:36 ` Richard Cochran
2010-05-18 16:23 ` Scott Wood
2010-05-17 15:41 ` Wolfgang Grandegger
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