1 files changed, 208 insertions, 75 deletions

diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c
index e7707747f56d..3042eaa13062 100644
--- a/drivers/hv/hv_util.c
+++ b/drivers/hv/hv_util.c
@@ -27,6 +27,9 @@
 #include <linux/sysctl.h>
 #include <linux/reboot.h>
 #include <linux/hyperv.h>
+#include <linux/clockchips.h>
+#include <linux/ptp_clock_kernel.h>
+#include <asm/mshyperv.h>
 
 #include "hyperv_vmbus.h"
 
@@ -57,7 +60,31 @@
 static int sd_srv_version;
 static int ts_srv_version;
 static int hb_srv_version;
-static int util_fw_version;
+
+#define SD_VER_COUNT 2
+static const int sd_versions[] = {
+	SD_VERSION,
+	SD_VERSION_1
+};
+
+#define TS_VER_COUNT 3
+static const int ts_versions[] = {
+	TS_VERSION,
+	TS_VERSION_3,
+	TS_VERSION_1
+};
+
+#define HB_VER_COUNT 2
+static const int hb_versions[] = {
+	HB_VERSION,
+	HB_VERSION_1
+};
+
+#define FW_VER_COUNT 2
+static const int fw_versions[] = {
+	UTIL_FW_VERSION,
+	UTIL_WS2K8_FW_VERSION
+};
 
 static void shutdown_onchannelcallback(void *context);
 static struct hv_util_service util_shutdown = {
@@ -118,7 +145,6 @@ static void shutdown_onchannelcallback(void *context)
 	struct shutdown_msg_data *shutdown_msg;
 
 	struct icmsg_hdr *icmsghdrp;
-	struct icmsg_negotiate *negop = NULL;
 
 	vmbus_recvpacket(channel, shut_txf_buf,
 			 PAGE_SIZE, &recvlen, &requestid);
@@ -128,9 +154,14 @@ static void shutdown_onchannelcallback(void *context)
 			sizeof(struct vmbuspipe_hdr)];
 
 		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
-			vmbus_prep_negotiate_resp(icmsghdrp, negop,
-					shut_txf_buf, util_fw_version,
-					sd_srv_version);
+			if (vmbus_prep_negotiate_resp(icmsghdrp, shut_txf_buf,
+					fw_versions, FW_VER_COUNT,
+					sd_versions, SD_VER_COUNT,
+					NULL, &sd_srv_version)) {
+				pr_info("Shutdown IC version %d.%d\n",
+					sd_srv_version >> 16,
+					sd_srv_version & 0xFFFF);
+			}
 		} else {
 			shutdown_msg =
 				(struct shutdown_msg_data *)&shut_txf_buf[
@@ -181,31 +212,17 @@ struct adj_time_work {
 
 static void hv_set_host_time(struct work_struct *work)
 {
-	struct adj_time_work	*wrk;
-	s64 host_tns;
-	u64 newtime;
-	struct timespec host_ts;
+	struct adj_time_work *wrk;
+	struct timespec64 host_ts;
+	u64 reftime, newtime;
 
 	wrk = container_of(work, struct adj_time_work, work);
 
-	newtime = wrk->host_time;
-	if (ts_srv_version > TS_VERSION_3) {
-		/*
-		 * Some latency has been introduced since Hyper-V generated
-		 * its time sample. Take that latency into account before
-		 * using TSC reference time sample from Hyper-V.
-		 *
-		 * This sample is given by TimeSync v4 and above hosts.
-		 */
-		u64 current_tick;
-
-		rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick);
-		newtime += (current_tick - wrk->ref_time);
-	}
-	host_tns = (newtime - WLTIMEDELTA) * 100;
-	host_ts = ns_to_timespec(host_tns);
+	reftime = hyperv_cs->read(hyperv_cs);
+	newtime = wrk->host_time + (reftime - wrk->ref_time);
+	host_ts = ns_to_timespec64((newtime - WLTIMEDELTA) * 100);
 
-	do_settimeofday(&host_ts);
+	do_settimeofday64(&host_ts);
 }
 
 /*
@@ -222,22 +239,60 @@ static void hv_set_host_time(struct work_struct *work)
  * to discipline the clock.
  */
 static struct adj_time_work  wrk;
-static inline void adj_guesttime(u64 hosttime, u64 reftime, u8 flags)
+
+/*
+ * The last time sample, received from the host. PTP device responds to
+ * requests by using this data and the current partition-wide time reference
+ * count.
+ */
+static struct {
+	u64				host_time;
+	u64				ref_time;
+	struct system_time_snapshot	snap;
+	spinlock_t			lock;
+} host_ts;
+
+static inline void adj_guesttime(u64 hosttime, u64 reftime, u8 adj_flags)
 {
+	unsigned long flags;
+	u64 cur_reftime;
 
 	/*
 	 * This check is safe since we are executing in the
-	 * interrupt context and time synch messages arre always
+	 * interrupt context and time synch messages are always
 	 * delivered on the same CPU.
 	 */
-	if (work_pending(&wrk.work))
-		return;
-
-	wrk.host_time = hosttime;
-	wrk.ref_time = reftime;
-	wrk.flags = flags;
-	if ((flags & (ICTIMESYNCFLAG_SYNC | ICTIMESYNCFLAG_SAMPLE)) != 0) {
+	if (adj_flags & ICTIMESYNCFLAG_SYNC) {
+		/* Queue a job to do do_settimeofday64() */
+		if (work_pending(&wrk.work))
+			return;
+
+		wrk.host_time = hosttime;
+		wrk.ref_time = reftime;
+		wrk.flags = adj_flags;
 		schedule_work(&wrk.work);
+	} else {
+		/*
+		 * Save the adjusted time sample from the host and the snapshot
+		 * of the current system time for PTP device.
+		 */
+		spin_lock_irqsave(&host_ts.lock, flags);
+
+		cur_reftime = hyperv_cs->read(hyperv_cs);
+		host_ts.host_time = hosttime;
+		host_ts.ref_time = cur_reftime;
+		ktime_get_snapshot(&host_ts.snap);
+
+		/*
+		 * TimeSync v4 messages contain reference time (guest's Hyper-V
+		 * clocksource read when the time sample was generated), we can
+		 * improve the precision by adding the delta between now and the
+		 * time of generation.
+		 */
+		if (ts_srv_version > TS_VERSION_3)
+			host_ts.host_time += (cur_reftime - reftime);
+
+		spin_unlock_irqrestore(&host_ts.lock, flags);
 	}
 }
 
@@ -253,7 +308,6 @@ static void timesync_onchannelcallback(void *context)
 	struct ictimesync_data *timedatap;
 	struct ictimesync_ref_data *refdata;
 	u8 *time_txf_buf = util_timesynch.recv_buffer;
-	struct icmsg_negotiate *negop = NULL;
 
 	vmbus_recvpacket(channel, time_txf_buf,
 			 PAGE_SIZE, &recvlen, &requestid);
@@ -263,12 +317,14 @@ static void timesync_onchannelcallback(void *context)
 				sizeof(struct vmbuspipe_hdr)];
 
 		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
-			vmbus_prep_negotiate_resp(icmsghdrp, negop,
-						time_txf_buf,
-						util_fw_version,
-						ts_srv_version);
-			pr_info("Using TimeSync version %d.%d\n",
-				ts_srv_version >> 16, ts_srv_version & 0xFFFF);
+			if (vmbus_prep_negotiate_resp(icmsghdrp, time_txf_buf,
+						fw_versions, FW_VER_COUNT,
+						ts_versions, TS_VER_COUNT,
+						NULL, &ts_srv_version)) {
+				pr_info("TimeSync IC version %d.%d\n",
+					ts_srv_version >> 16,
+					ts_srv_version & 0xFFFF);
+			}
 		} else {
 			if (ts_srv_version > TS_VERSION_3) {
 				refdata = (struct ictimesync_ref_data *)
@@ -312,7 +368,6 @@ static void heartbeat_onchannelcallback(void *context)
 	struct icmsg_hdr *icmsghdrp;
 	struct heartbeat_msg_data *heartbeat_msg;
 	u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
-	struct icmsg_negotiate *negop = NULL;
 
 	while (1) {
 
@@ -326,9 +381,16 @@ static void heartbeat_onchannelcallback(void *context)
 				sizeof(struct vmbuspipe_hdr)];
 
 		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
-			vmbus_prep_negotiate_resp(icmsghdrp, negop,
-				hbeat_txf_buf, util_fw_version,
-				hb_srv_version);
+			if (vmbus_prep_negotiate_resp(icmsghdrp,
+					hbeat_txf_buf,
+					fw_versions, FW_VER_COUNT,
+					hb_versions, HB_VER_COUNT,
+					NULL, &hb_srv_version)) {
+
+				pr_info("Heartbeat IC version %d.%d\n",
+					hb_srv_version >> 16,
+					hb_srv_version & 0xFFFF);
+			}
 		} else {
 			heartbeat_msg =
 				(struct heartbeat_msg_data *)&hbeat_txf_buf[
@@ -373,38 +435,10 @@ static int util_probe(struct hv_device *dev,
 	 * Turn off batched reading for all util drivers before we open the
 	 * channel.
 	 */
-
-	set_channel_read_state(dev->channel, false);
+	set_channel_read_mode(dev->channel, HV_CALL_DIRECT);
 
 	hv_set_drvdata(dev, srv);
 
-	/*
-	 * Based on the host; initialize the framework and
-	 * service version numbers we will negotiate.
-	 */
-	switch (vmbus_proto_version) {
-	case (VERSION_WS2008):
-		util_fw_version = UTIL_WS2K8_FW_VERSION;
-		sd_srv_version = SD_VERSION_1;
-		ts_srv_version = TS_VERSION_1;
-		hb_srv_version = HB_VERSION_1;
-		break;
-	case VERSION_WIN7:
-	case VERSION_WIN8:
-	case VERSION_WIN8_1:
-		util_fw_version = UTIL_FW_VERSION;
-		sd_srv_version = SD_VERSION;
-		ts_srv_version = TS_VERSION_3;
-		hb_srv_version = HB_VERSION;
-		break;
-	case VERSION_WIN10:
-	default:
-		util_fw_version = UTIL_FW_VERSION;
-		sd_srv_version = SD_VERSION;
-		ts_srv_version = TS_VERSION;
-		hb_srv_version = HB_VERSION;
-	}
-
 	ret = vmbus_open(dev->channel, 4 * PAGE_SIZE, 4 * PAGE_SIZE, NULL, 0,
 			srv->util_cb, dev->channel);
 	if (ret)
@@ -470,14 +504,113 @@ static  struct hv_driver util_drv = {
 	.remove =  util_remove,
 };
 
+static int hv_ptp_enable(struct ptp_clock_info *info,
+			 struct ptp_clock_request *request, int on)
+{
+	return -EOPNOTSUPP;
+}
+
+static int hv_ptp_settime(struct ptp_clock_info *p, const struct timespec64 *ts)
+{
+	return -EOPNOTSUPP;
+}
+
+static int hv_ptp_adjfreq(struct ptp_clock_info *ptp, s32 delta)
+{
+	return -EOPNOTSUPP;
+}
+static int hv_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
+{
+	return -EOPNOTSUPP;
+}
+
+static int hv_ptp_gettime(struct ptp_clock_info *info, struct timespec64 *ts)
+{
+	unsigned long flags;
+	u64 newtime, reftime;
+
+	spin_lock_irqsave(&host_ts.lock, flags);
+	reftime = hyperv_cs->read(hyperv_cs);
+	newtime = host_ts.host_time + (reftime - host_ts.ref_time);
+	*ts = ns_to_timespec64((newtime - WLTIMEDELTA) * 100);
+	spin_unlock_irqrestore(&host_ts.lock, flags);
+
+	return 0;
+}
+
+static int hv_ptp_get_syncdevicetime(ktime_t *device,
+				     struct system_counterval_t *system,
+				     void *ctx)
+{
+	system->cs = hyperv_cs;
+	system->cycles = host_ts.ref_time;
+	*device = ns_to_ktime((host_ts.host_time - WLTIMEDELTA) * 100);
+
+	return 0;
+}
+
+static int hv_ptp_getcrosststamp(struct ptp_clock_info *ptp,
+				 struct system_device_crosststamp *xtstamp)
+{
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&host_ts.lock, flags);
+
+	/*
+	 * host_ts contains the last time sample from the host and the snapshot
+	 * of system time. We don't need to calculate the time delta between
+	 * the reception and now as get_device_system_crosststamp() does the
+	 * required interpolation.
+	 */
+	ret = get_device_system_crosststamp(hv_ptp_get_syncdevicetime,
+					    NULL, &host_ts.snap, xtstamp);
+
+	spin_unlock_irqrestore(&host_ts.lock, flags);
+
+	return ret;
+}
+
+static struct ptp_clock_info ptp_hyperv_info = {
+	.name		= "hyperv",
+	.enable         = hv_ptp_enable,
+	.adjtime        = hv_ptp_adjtime,
+	.adjfreq        = hv_ptp_adjfreq,
+	.gettime64      = hv_ptp_gettime,
+	.getcrosststamp = hv_ptp_getcrosststamp,
+	.settime64      = hv_ptp_settime,
+	.owner		= THIS_MODULE,
+};
+
+static struct ptp_clock *hv_ptp_clock;
+
 static int hv_timesync_init(struct hv_util_service *srv)
 {
+	/* TimeSync requires Hyper-V clocksource. */
+	if (!hyperv_cs)
+		return -ENODEV;
+
 	INIT_WORK(&wrk.work, hv_set_host_time);
+
+	/*
+	 * ptp_clock_register() returns NULL when CONFIG_PTP_1588_CLOCK is
+	 * disabled but the driver is still useful without the PTP device
+	 * as it still handles the ICTIMESYNCFLAG_SYNC case.
+	 */
+	hv_ptp_clock = ptp_clock_register(&ptp_hyperv_info, NULL);
+	if (IS_ERR_OR_NULL(hv_ptp_clock)) {
+		pr_err("cannot register PTP clock: %ld\n",
+		       PTR_ERR(hv_ptp_clock));
+		hv_ptp_clock = NULL;
+	}
+
 	return 0;
 }
 
 static void hv_timesync_deinit(void)
 {
+	if (hv_ptp_clock)
+		ptp_clock_unregister(hv_ptp_clock);
 	cancel_work_sync(&wrk.work);
 }