5 files changed, 461 insertions, 3 deletions

diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile
index 8673d1743faa..28a6fe342d3e 100644
--- a/drivers/ptp/Makefile
+++ b/drivers/ptp/Makefile
@@ -3,7 +3,7 @@
 # Makefile for PTP 1588 clock support.
 #
 
-ptp-y					:= ptp_clock.o ptp_chardev.o ptp_sysfs.o
+ptp-y					:= ptp_clock.o ptp_chardev.o ptp_sysfs.o ptp_vclock.o
 ptp_kvm-$(CONFIG_X86)			:= ptp_kvm_x86.o ptp_kvm_common.o
 ptp_kvm-$(CONFIG_HAVE_ARM_SMCCC)	:= ptp_kvm_arm.o ptp_kvm_common.o
 obj-$(CONFIG_PTP_1588_CLOCK)		+= ptp.o
diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
index a23a37a4d5dc..4dfc52e06704 100644
--- a/drivers/ptp/ptp_clock.c
+++ b/drivers/ptp/ptp_clock.c
@@ -24,10 +24,11 @@
 #define PTP_PPS_EVENT PPS_CAPTUREASSERT
 #define PTP_PPS_MODE (PTP_PPS_DEFAULTS | PPS_CANWAIT | PPS_TSFMT_TSPEC)
 
+struct class *ptp_class;
+
 /* private globals */
 
 static dev_t ptp_devt;
-static struct class *ptp_class;
 
 static DEFINE_IDA(ptp_clocks_map);
 
@@ -76,6 +77,11 @@ static int ptp_clock_settime(struct posix_clock *pc, const struct timespec64 *tp
 {
 	struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
 
+	if (ptp_vclock_in_use(ptp)) {
+		pr_err("ptp: virtual clock in use\n");
+		return -EBUSY;
+	}
+
 	return  ptp->info->settime64(ptp->info, tp);
 }
 
@@ -97,6 +103,11 @@ static int ptp_clock_adjtime(struct posix_clock *pc, struct __kernel_timex *tx)
 	struct ptp_clock_info *ops;
 	int err = -EOPNOTSUPP;
 
+	if (ptp_vclock_in_use(ptp)) {
+		pr_err("ptp: virtual clock in use\n");
+		return -EBUSY;
+	}
+
 	ops = ptp->info;
 
 	if (tx->modes & ADJ_SETOFFSET) {
@@ -161,6 +172,7 @@ static void ptp_clock_release(struct device *dev)
 	ptp_cleanup_pin_groups(ptp);
 	mutex_destroy(&ptp->tsevq_mux);
 	mutex_destroy(&ptp->pincfg_mux);
+	mutex_destroy(&ptp->n_vclocks_mux);
 	ida_simple_remove(&ptp_clocks_map, ptp->index);
 	kfree(ptp);
 }
@@ -185,6 +197,7 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
 {
 	struct ptp_clock *ptp;
 	int err = 0, index, major = MAJOR(ptp_devt);
+	size_t size;
 
 	if (info->n_alarm > PTP_MAX_ALARMS)
 		return ERR_PTR(-EINVAL);
@@ -208,6 +221,7 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
 	spin_lock_init(&ptp->tsevq.lock);
 	mutex_init(&ptp->tsevq_mux);
 	mutex_init(&ptp->pincfg_mux);
+	mutex_init(&ptp->n_vclocks_mux);
 	init_waitqueue_head(&ptp->tsev_wq);
 
 	if (ptp->info->do_aux_work) {
@@ -218,7 +232,22 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
 			pr_err("failed to create ptp aux_worker %d\n", err);
 			goto kworker_err;
 		}
-		ptp->pps_source->lookup_cookie = ptp;
+	}
+
+	/* PTP virtual clock is being registered under physical clock */
+	if (parent && parent->class && parent->class->name &&
+	    strcmp(parent->class->name, "ptp") == 0)
+		ptp->is_virtual_clock = true;
+
+	if (!ptp->is_virtual_clock) {
+		ptp->max_vclocks = PTP_DEFAULT_MAX_VCLOCKS;
+
+		size = sizeof(int) * ptp->max_vclocks;
+		ptp->vclock_index = kzalloc(size, GFP_KERNEL);
+		if (!ptp->vclock_index) {
+			err = -ENOMEM;
+			goto no_mem_for_vclocks;
+		}
 	}
 
 	err = ptp_populate_pin_groups(ptp);
@@ -238,6 +267,7 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
 			pr_err("failed to register pps source\n");
 			goto no_pps;
 		}
+		ptp->pps_source->lookup_cookie = ptp;
 	}
 
 	/* Initialize a new device of our class in our clock structure. */
@@ -265,11 +295,14 @@ no_clock:
 no_pps:
 	ptp_cleanup_pin_groups(ptp);
 no_pin_groups:
+	kfree(ptp->vclock_index);
+no_mem_for_vclocks:
 	if (ptp->kworker)
 		kthread_destroy_worker(ptp->kworker);
 kworker_err:
 	mutex_destroy(&ptp->tsevq_mux);
 	mutex_destroy(&ptp->pincfg_mux);
+	mutex_destroy(&ptp->n_vclocks_mux);
 	ida_simple_remove(&ptp_clocks_map, index);
 no_slot:
 	kfree(ptp);
@@ -280,9 +313,16 @@ EXPORT_SYMBOL(ptp_clock_register);
 
 int ptp_clock_unregister(struct ptp_clock *ptp)
 {
+	if (ptp_vclock_in_use(ptp)) {
+		pr_err("ptp: virtual clock in use\n");
+		return -EBUSY;
+	}
+
 	ptp->defunct = 1;
 	wake_up_interruptible(&ptp->tsev_wq);
 
+	kfree(ptp->vclock_index);
+
 	if (ptp->kworker) {
 		kthread_cancel_delayed_work_sync(&ptp->aux_work);
 		kthread_destroy_worker(ptp->kworker);
diff --git a/drivers/ptp/ptp_private.h b/drivers/ptp/ptp_private.h
index 6b97155148f1..dba6be477067 100644
--- a/drivers/ptp/ptp_private.h
+++ b/drivers/ptp/ptp_private.h
@@ -18,6 +18,7 @@
 
 #define PTP_MAX_TIMESTAMPS 128
 #define PTP_BUF_TIMESTAMPS 30
+#define PTP_DEFAULT_MAX_VCLOCKS 20
 
 struct timestamp_event_queue {
 	struct ptp_extts_event buf[PTP_MAX_TIMESTAMPS];
@@ -46,6 +47,24 @@ struct ptp_clock {
 	const struct attribute_group *pin_attr_groups[2];
 	struct kthread_worker *kworker;
 	struct kthread_delayed_work aux_work;
+	unsigned int max_vclocks;
+	unsigned int n_vclocks;
+	int *vclock_index;
+	struct mutex n_vclocks_mux; /* protect concurrent n_vclocks access */
+	bool is_virtual_clock;
+};
+
+#define info_to_vclock(d) container_of((d), struct ptp_vclock, info)
+#define cc_to_vclock(d) container_of((d), struct ptp_vclock, cc)
+#define dw_to_vclock(d) container_of((d), struct ptp_vclock, refresh_work)
+
+struct ptp_vclock {
+	struct ptp_clock *pclock;
+	struct ptp_clock_info info;
+	struct ptp_clock *clock;
+	struct cyclecounter cc;
+	struct timecounter tc;
+	spinlock_t lock;	/* protects tc/cc */
 };
 
 /*
@@ -61,6 +80,24 @@ static inline int queue_cnt(struct timestamp_event_queue *q)
 	return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt;
 }
 
+/* Check if ptp virtual clock is in use */
+static inline bool ptp_vclock_in_use(struct ptp_clock *ptp)
+{
+	bool in_use = false;
+
+	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
+		return true;
+
+	if (!ptp->is_virtual_clock && ptp->n_vclocks)
+		in_use = true;
+
+	mutex_unlock(&ptp->n_vclocks_mux);
+
+	return in_use;
+}
+
+extern struct class *ptp_class;
+
 /*
  * see ptp_chardev.c
  */
@@ -89,4 +126,6 @@ extern const struct attribute_group *ptp_groups[];
 int ptp_populate_pin_groups(struct ptp_clock *ptp);
 void ptp_cleanup_pin_groups(struct ptp_clock *ptp);
 
+struct ptp_vclock *ptp_vclock_register(struct ptp_clock *pclock);
+void ptp_vclock_unregister(struct ptp_vclock *vclock);
 #endif
diff --git a/drivers/ptp/ptp_sysfs.c b/drivers/ptp/ptp_sysfs.c
index be076a91e20e..b3d96b747292 100644
--- a/drivers/ptp/ptp_sysfs.c
+++ b/drivers/ptp/ptp_sysfs.c
@@ -3,6 +3,7 @@
  * PTP 1588 clock support - sysfs interface.
  *
  * Copyright (C) 2010 OMICRON electronics GmbH
+ * Copyright 2021 NXP
  */
 #include <linux/capability.h>
 #include <linux/slab.h>
@@ -148,6 +149,159 @@ out:
 }
 static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store);
 
+static int unregister_vclock(struct device *dev, void *data)
+{
+	struct ptp_clock *ptp = dev_get_drvdata(dev);
+	struct ptp_clock_info *info = ptp->info;
+	struct ptp_vclock *vclock;
+	u8 *num = data;
+
+	vclock = info_to_vclock(info);
+	dev_info(dev->parent, "delete virtual clock ptp%d\n",
+		 vclock->clock->index);
+
+	ptp_vclock_unregister(vclock);
+	(*num)--;
+
+	/* For break. Not error. */
+	if (*num == 0)
+		return -EINVAL;
+
+	return 0;
+}
+
+static ssize_t n_vclocks_show(struct device *dev,
+			      struct device_attribute *attr, char *page)
+{
+	struct ptp_clock *ptp = dev_get_drvdata(dev);
+	ssize_t size;
+
+	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
+		return -ERESTARTSYS;
+
+	size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->n_vclocks);
+
+	mutex_unlock(&ptp->n_vclocks_mux);
+
+	return size;
+}
+
+static ssize_t n_vclocks_store(struct device *dev,
+			       struct device_attribute *attr,
+			       const char *buf, size_t count)
+{
+	struct ptp_clock *ptp = dev_get_drvdata(dev);
+	struct ptp_vclock *vclock;
+	int err = -EINVAL;
+	u32 num, i;
+
+	if (kstrtou32(buf, 0, &num))
+		return err;
+
+	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
+		return -ERESTARTSYS;
+
+	if (num > ptp->max_vclocks) {
+		dev_err(dev, "max value is %d\n", ptp->max_vclocks);
+		goto out;
+	}
+
+	/* Need to create more vclocks */
+	if (num > ptp->n_vclocks) {
+		for (i = 0; i < num - ptp->n_vclocks; i++) {
+			vclock = ptp_vclock_register(ptp);
+			if (!vclock)
+				goto out;
+
+			*(ptp->vclock_index + ptp->n_vclocks + i) =
+				vclock->clock->index;
+
+			dev_info(dev, "new virtual clock ptp%d\n",
+				 vclock->clock->index);
+		}
+	}
+
+	/* Need to delete vclocks */
+	if (num < ptp->n_vclocks) {
+		i = ptp->n_vclocks - num;
+		device_for_each_child_reverse(dev, &i,
+					      unregister_vclock);
+
+		for (i = 1; i <= ptp->n_vclocks - num; i++)
+			*(ptp->vclock_index + ptp->n_vclocks - i) = -1;
+	}
+
+	if (num == 0)
+		dev_info(dev, "only physical clock in use now\n");
+	else
+		dev_info(dev, "guarantee physical clock free running\n");
+
+	ptp->n_vclocks = num;
+	mutex_unlock(&ptp->n_vclocks_mux);
+
+	return count;
+out:
+	mutex_unlock(&ptp->n_vclocks_mux);
+	return err;
+}
+static DEVICE_ATTR_RW(n_vclocks);
+
+static ssize_t max_vclocks_show(struct device *dev,
+				struct device_attribute *attr, char *page)
+{
+	struct ptp_clock *ptp = dev_get_drvdata(dev);
+	ssize_t size;
+
+	size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->max_vclocks);
+
+	return size;
+}
+
+static ssize_t max_vclocks_store(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf, size_t count)
+{
+	struct ptp_clock *ptp = dev_get_drvdata(dev);
+	unsigned int *vclock_index;
+	int err = -EINVAL;
+	size_t size;
+	u32 max;
+
+	if (kstrtou32(buf, 0, &max) || max == 0)
+		return -EINVAL;
+
+	if (max == ptp->max_vclocks)
+		return count;
+
+	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
+		return -ERESTARTSYS;
+
+	if (max < ptp->n_vclocks)
+		goto out;
+
+	size = sizeof(int) * max;
+	vclock_index = kzalloc(size, GFP_KERNEL);
+	if (!vclock_index) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	size = sizeof(int) * ptp->n_vclocks;
+	memcpy(vclock_index, ptp->vclock_index, size);
+
+	kfree(ptp->vclock_index);
+	ptp->vclock_index = vclock_index;
+	ptp->max_vclocks = max;
+
+	mutex_unlock(&ptp->n_vclocks_mux);
+
+	return count;
+out:
+	mutex_unlock(&ptp->n_vclocks_mux);
+	return err;
+}
+static DEVICE_ATTR_RW(max_vclocks);
+
 static struct attribute *ptp_attrs[] = {
 	&dev_attr_clock_name.attr,
 
@@ -162,6 +316,8 @@ static struct attribute *ptp_attrs[] = {
 	&dev_attr_fifo.attr,
 	&dev_attr_period.attr,
 	&dev_attr_pps_enable.attr,
+	&dev_attr_n_vclocks.attr,
+	&dev_attr_max_vclocks.attr,
 	NULL
 };
 
@@ -183,6 +339,10 @@ static umode_t ptp_is_attribute_visible(struct kobject *kobj,
 	} else if (attr == &dev_attr_pps_enable.attr) {
 		if (!info->pps)
 			mode = 0;
+	} else if (attr == &dev_attr_n_vclocks.attr ||
+		   attr == &dev_attr_max_vclocks.attr) {
+		if (ptp->is_virtual_clock)
+			mode = 0;
 	}
 
 	return mode;
diff --git a/drivers/ptp/ptp_vclock.c b/drivers/ptp/ptp_vclock.c
new file mode 100644
index 000000000000..e0f87c57749a
--- /dev/null
+++ b/drivers/ptp/ptp_vclock.c
@@ -0,0 +1,219 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * PTP virtual clock driver
+ *
+ * Copyright 2021 NXP
+ */
+#include <linux/slab.h>
+#include "ptp_private.h"
+
+#define PTP_VCLOCK_CC_SHIFT		31
+#define PTP_VCLOCK_CC_MULT		(1 << PTP_VCLOCK_CC_SHIFT)
+#define PTP_VCLOCK_FADJ_SHIFT		9
+#define PTP_VCLOCK_FADJ_DENOMINATOR	15625ULL
+#define PTP_VCLOCK_REFRESH_INTERVAL	(HZ * 2)
+
+static int ptp_vclock_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
+{
+	struct ptp_vclock *vclock = info_to_vclock(ptp);
+	unsigned long flags;
+	s64 adj;
+
+	adj = (s64)scaled_ppm << PTP_VCLOCK_FADJ_SHIFT;
+	adj = div_s64(adj, PTP_VCLOCK_FADJ_DENOMINATOR);
+
+	spin_lock_irqsave(&vclock->lock, flags);
+	timecounter_read(&vclock->tc);
+	vclock->cc.mult = PTP_VCLOCK_CC_MULT + adj;
+	spin_unlock_irqrestore(&vclock->lock, flags);
+
+	return 0;
+}
+
+static int ptp_vclock_adjtime(struct ptp_clock_info *ptp, s64 delta)
+{
+	struct ptp_vclock *vclock = info_to_vclock(ptp);
+	unsigned long flags;
+
+	spin_lock_irqsave(&vclock->lock, flags);
+	timecounter_adjtime(&vclock->tc, delta);
+	spin_unlock_irqrestore(&vclock->lock, flags);
+
+	return 0;
+}
+
+static int ptp_vclock_gettime(struct ptp_clock_info *ptp,
+			      struct timespec64 *ts)
+{
+	struct ptp_vclock *vclock = info_to_vclock(ptp);
+	unsigned long flags;
+	u64 ns;
+
+	spin_lock_irqsave(&vclock->lock, flags);
+	ns = timecounter_read(&vclock->tc);
+	spin_unlock_irqrestore(&vclock->lock, flags);
+	*ts = ns_to_timespec64(ns);
+
+	return 0;
+}
+
+static int ptp_vclock_settime(struct ptp_clock_info *ptp,
+			      const struct timespec64 *ts)
+{
+	struct ptp_vclock *vclock = info_to_vclock(ptp);
+	u64 ns = timespec64_to_ns(ts);
+	unsigned long flags;
+
+	spin_lock_irqsave(&vclock->lock, flags);
+	timecounter_init(&vclock->tc, &vclock->cc, ns);
+	spin_unlock_irqrestore(&vclock->lock, flags);
+
+	return 0;
+}
+
+static long ptp_vclock_refresh(struct ptp_clock_info *ptp)
+{
+	struct ptp_vclock *vclock = info_to_vclock(ptp);
+	struct timespec64 ts;
+
+	ptp_vclock_gettime(&vclock->info, &ts);
+
+	return PTP_VCLOCK_REFRESH_INTERVAL;
+}
+
+static const struct ptp_clock_info ptp_vclock_info = {
+	.owner		= THIS_MODULE,
+	.name		= "ptp virtual clock",
+	/* The maximum ppb value that long scaled_ppm can support */
+	.max_adj	= 32767999,
+	.adjfine	= ptp_vclock_adjfine,
+	.adjtime	= ptp_vclock_adjtime,
+	.gettime64	= ptp_vclock_gettime,
+	.settime64	= ptp_vclock_settime,
+	.do_aux_work	= ptp_vclock_refresh,
+};
+
+static u64 ptp_vclock_read(const struct cyclecounter *cc)
+{
+	struct ptp_vclock *vclock = cc_to_vclock(cc);
+	struct ptp_clock *ptp = vclock->pclock;
+	struct timespec64 ts = {};
+
+	if (ptp->info->gettimex64)
+		ptp->info->gettimex64(ptp->info, &ts, NULL);
+	else
+		ptp->info->gettime64(ptp->info, &ts);
+
+	return timespec64_to_ns(&ts);
+}
+
+static const struct cyclecounter ptp_vclock_cc = {
+	.read	= ptp_vclock_read,
+	.mask	= CYCLECOUNTER_MASK(32),
+	.mult	= PTP_VCLOCK_CC_MULT,
+	.shift	= PTP_VCLOCK_CC_SHIFT,
+};
+
+struct ptp_vclock *ptp_vclock_register(struct ptp_clock *pclock)
+{
+	struct ptp_vclock *vclock;
+
+	vclock = kzalloc(sizeof(*vclock), GFP_KERNEL);
+	if (!vclock)
+		return NULL;
+
+	vclock->pclock = pclock;
+	vclock->info = ptp_vclock_info;
+	vclock->cc = ptp_vclock_cc;
+
+	snprintf(vclock->info.name, PTP_CLOCK_NAME_LEN, "ptp%d_virt",
+		 pclock->index);
+
+	spin_lock_init(&vclock->lock);
+
+	vclock->clock = ptp_clock_register(&vclock->info, &pclock->dev);
+	if (IS_ERR_OR_NULL(vclock->clock)) {
+		kfree(vclock);
+		return NULL;
+	}
+
+	timecounter_init(&vclock->tc, &vclock->cc, 0);
+	ptp_schedule_worker(vclock->clock, PTP_VCLOCK_REFRESH_INTERVAL);
+
+	return vclock;
+}
+
+void ptp_vclock_unregister(struct ptp_vclock *vclock)
+{
+	ptp_clock_unregister(vclock->clock);
+	kfree(vclock);
+}
+
+int ptp_get_vclocks_index(int pclock_index, int **vclock_index)
+{
+	char name[PTP_CLOCK_NAME_LEN] = "";
+	struct ptp_clock *ptp;
+	struct device *dev;
+	int num = 0;
+
+	if (pclock_index < 0)
+		return num;
+
+	snprintf(name, PTP_CLOCK_NAME_LEN, "ptp%d", pclock_index);
+	dev = class_find_device_by_name(ptp_class, name);
+	if (!dev)
+		return num;
+
+	ptp = dev_get_drvdata(dev);
+
+	if (mutex_lock_interruptible(&ptp->n_vclocks_mux)) {
+		put_device(dev);
+		return num;
+	}
+
+	*vclock_index = kzalloc(sizeof(int) * ptp->n_vclocks, GFP_KERNEL);
+	if (!(*vclock_index))
+		goto out;
+
+	memcpy(*vclock_index, ptp->vclock_index, sizeof(int) * ptp->n_vclocks);
+	num = ptp->n_vclocks;
+out:
+	mutex_unlock(&ptp->n_vclocks_mux);
+	put_device(dev);
+	return num;
+}
+EXPORT_SYMBOL(ptp_get_vclocks_index);
+
+void ptp_convert_timestamp(struct skb_shared_hwtstamps *hwtstamps,
+			   int vclock_index)
+{
+	char name[PTP_CLOCK_NAME_LEN] = "";
+	struct ptp_vclock *vclock;
+	struct ptp_clock *ptp;
+	unsigned long flags;
+	struct device *dev;
+	u64 ns;
+
+	snprintf(name, PTP_CLOCK_NAME_LEN, "ptp%d", vclock_index);
+	dev = class_find_device_by_name(ptp_class, name);
+	if (!dev)
+		return;
+
+	ptp = dev_get_drvdata(dev);
+	if (!ptp->is_virtual_clock) {
+		put_device(dev);
+		return;
+	}
+
+	vclock = info_to_vclock(ptp->info);
+
+	ns = ktime_to_ns(hwtstamps->hwtstamp);
+
+	spin_lock_irqsave(&vclock->lock, flags);
+	ns = timecounter_cyc2time(&vclock->tc, ns);
+	spin_unlock_irqrestore(&vclock->lock, flags);
+
+	put_device(dev);
+	hwtstamps->hwtstamp = ns_to_ktime(ns);
+}
+EXPORT_SYMBOL(ptp_convert_timestamp);