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authorEdward Cree <ecree@solarflare.com>2018-01-25 17:27:40 +0000
committerDavid S. Miller <davem@davemloft.net>2018-01-25 16:05:15 -0500
commit1280c0f8aafc4c09c59c576c8d50f367070b2619 (patch)
treeed1d349c753ab408604ef6dcd7bb5037c5e5c3f2 /drivers/net/ethernet/sfc/ptp.c
parent04796f4c4dc4ac4c4f405c22e20dc9ae1068eea5 (diff)
sfc: support second + quarter ns time format for receive datapath
The time_format that we stash in the PTP data structure is never referenced, so we can remove it. Instead, store the information needed to interpret sync event timestamps. Also rolls in a couple of other related minor PTP fixes. Based on patches by Bert Kenward <bkenward@solarflare.com> and Laurence Evans <levans@solarflare.com>. Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/sfc/ptp.c')
-rw-r--r--drivers/net/ethernet/sfc/ptp.c139
1 files changed, 106 insertions, 33 deletions
diff --git a/drivers/net/ethernet/sfc/ptp.c b/drivers/net/ethernet/sfc/ptp.c
index 63c2b25f9281..196b0768b2f2 100644
--- a/drivers/net/ethernet/sfc/ptp.c
+++ b/drivers/net/ethernet/sfc/ptp.c
@@ -233,9 +233,17 @@ struct efx_ptp_timeset {
* @config: Current timestamp configuration
* @enabled: PTP operation enabled
* @mode: Mode in which PTP operating (PTP version)
- * @time_format: Time format supported by this NIC
* @ns_to_nic_time: Function to convert from scalar nanoseconds to NIC time
* @nic_to_kernel_time: Function to convert from NIC to kernel time
+ * @nic_time.minor_max: Wrap point for NIC minor times
+ * @nic_time.sync_event_diff_min: Minimum acceptable difference between time
+ * in packet prefix and last MCDI time sync event i.e. how much earlier than
+ * the last sync event time a packet timestamp can be.
+ * @nic_time.sync_event_diff_max: Maximum acceptable difference between time
+ * in packet prefix and last MCDI time sync event i.e. how much later than
+ * the last sync event time a packet timestamp can be.
+ * @nic_time.sync_event_minor_shift: Shift required to make minor time from
+ * field in MCDI time sync event.
* @min_synchronisation_ns: Minimum acceptable corrected sync window
* @capabilities: Capabilities flags from the NIC
* @ts_corrections.ptp_tx: Required driver correction of PTP packet transmit
@@ -292,10 +300,15 @@ struct efx_ptp_data {
struct hwtstamp_config config;
bool enabled;
unsigned int mode;
- unsigned int time_format;
void (*ns_to_nic_time)(s64 ns, u32 *nic_major, u32 *nic_minor);
ktime_t (*nic_to_kernel_time)(u32 nic_major, u32 nic_minor,
s32 correction);
+ struct {
+ u32 minor_max;
+ u32 sync_event_diff_min;
+ u32 sync_event_diff_max;
+ unsigned int sync_event_minor_shift;
+ } nic_time;
unsigned int min_synchronisation_ns;
struct {
s32 ptp_tx;
@@ -500,6 +513,32 @@ static ktime_t efx_ptp_s27_to_ktime_correction(u32 nic_major, u32 nic_minor,
return efx_ptp_s27_to_ktime(nic_major, nic_minor);
}
+/* For Medford2 platforms the time is in seconds and quarter nanoseconds. */
+static void efx_ptp_ns_to_s_qns(s64 ns, u32 *nic_major, u32 *nic_minor)
+{
+ struct timespec64 ts = ns_to_timespec64(ns);
+
+ *nic_major = (u32)ts.tv_sec;
+ *nic_minor = ts.tv_nsec * 4;
+}
+
+static ktime_t efx_ptp_s_qns_to_ktime_correction(u32 nic_major, u32 nic_minor,
+ s32 correction)
+{
+ ktime_t kt;
+
+ nic_minor = DIV_ROUND_CLOSEST(nic_minor, 4);
+ correction = DIV_ROUND_CLOSEST(correction, 4);
+
+ kt = ktime_set(nic_major, nic_minor);
+
+ if (correction >= 0)
+ kt = ktime_add_ns(kt, (u64)correction);
+ else
+ kt = ktime_sub_ns(kt, (u64)-correction);
+ return kt;
+}
+
struct efx_channel *efx_ptp_channel(struct efx_nic *efx)
{
return efx->ptp_data ? efx->ptp_data->channel : NULL;
@@ -519,7 +558,8 @@ static u32 last_sync_timestamp_major(struct efx_nic *efx)
* 48 bits long and provides meta-information in the top 2 bits.
*/
static ktime_t
-efx_ptp_mac_s27_to_ktime_correction(struct efx_nic *efx,
+efx_ptp_mac_nic_to_ktime_correction(struct efx_nic *efx,
+ struct efx_ptp_data *ptp,
u32 nic_major, u32 nic_minor,
s32 correction)
{
@@ -531,8 +571,8 @@ efx_ptp_mac_s27_to_ktime_correction(struct efx_nic *efx,
nic_major &= 0xffff;
nic_major |= (last_sync_timestamp_major(efx) & 0xffff0000);
- kt = efx_ptp_s27_to_ktime_correction(nic_major, nic_minor,
- correction);
+ kt = ptp->nic_to_kernel_time(nic_major, nic_minor,
+ correction);
}
return kt;
}
@@ -544,7 +584,7 @@ ktime_t efx_ptp_nic_to_kernel_time(struct efx_tx_queue *tx_queue)
ktime_t kt;
if (efx_ptp_use_mac_tx_timestamps(efx))
- kt = efx_ptp_mac_s27_to_ktime_correction(efx,
+ kt = efx_ptp_mac_nic_to_ktime_correction(efx, ptp,
tx_queue->completed_timestamp_major,
tx_queue->completed_timestamp_minor,
ptp->ts_corrections.general_tx);
@@ -587,23 +627,49 @@ static int efx_ptp_get_attributes(struct efx_nic *efx)
return rc;
}
- if (fmt == MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_27FRACTION) {
+ switch (fmt) {
+ case MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_27FRACTION:
ptp->ns_to_nic_time = efx_ptp_ns_to_s27;
ptp->nic_to_kernel_time = efx_ptp_s27_to_ktime_correction;
- } else if (fmt == MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_NANOSECONDS) {
+ ptp->nic_time.minor_max = 1 << 27;
+ ptp->nic_time.sync_event_minor_shift = 19;
+ break;
+ case MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_NANOSECONDS:
ptp->ns_to_nic_time = efx_ptp_ns_to_s_ns;
ptp->nic_to_kernel_time = efx_ptp_s_ns_to_ktime_correction;
- } else {
+ ptp->nic_time.minor_max = 1000000000;
+ ptp->nic_time.sync_event_minor_shift = 22;
+ break;
+ case MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_QTR_NANOSECONDS:
+ ptp->ns_to_nic_time = efx_ptp_ns_to_s_qns;
+ ptp->nic_to_kernel_time = efx_ptp_s_qns_to_ktime_correction;
+ ptp->nic_time.minor_max = 4000000000;
+ ptp->nic_time.sync_event_minor_shift = 24;
+ break;
+ default:
return -ERANGE;
}
- /* MC_CMD_PTP_OP_GET_ATTRIBUTES is an extended version of an older
- * operation MC_CMD_PTP_OP_GET_TIME_FORMAT that also returns a value
- * to use for the minimum acceptable corrected synchronization window.
+ /* Precalculate acceptable difference between the minor time in the
+ * packet prefix and the last MCDI time sync event. We expect the
+ * packet prefix timestamp to be after of sync event by up to one
+ * sync event interval (0.25s) but we allow it to exceed this by a
+ * fuzz factor of (0.1s)
+ */
+ ptp->nic_time.sync_event_diff_min = ptp->nic_time.minor_max
+ - (ptp->nic_time.minor_max / 10);
+ ptp->nic_time.sync_event_diff_max = (ptp->nic_time.minor_max / 4)
+ + (ptp->nic_time.minor_max / 10);
+
+ /* MC_CMD_PTP_OP_GET_ATTRIBUTES has been extended twice from an older
+ * operation MC_CMD_PTP_OP_GET_TIME_FORMAT. The function now may return
+ * a value to use for the minimum acceptable corrected synchronization
+ * window and may return further capabilities.
* If we have the extra information store it. For older firmware that
* does not implement the extended command use the default value.
*/
- if (rc == 0 && out_len >= MC_CMD_PTP_OUT_GET_ATTRIBUTES_LEN)
+ if (rc == 0 &&
+ out_len >= MC_CMD_PTP_OUT_GET_ATTRIBUTES_CAPABILITIES_OFST)
ptp->min_synchronisation_ns =
MCDI_DWORD(outbuf,
PTP_OUT_GET_ATTRIBUTES_SYNC_WINDOW_MIN);
@@ -1855,9 +1921,20 @@ void efx_ptp_event(struct efx_nic *efx, efx_qword_t *ev)
void efx_time_sync_event(struct efx_channel *channel, efx_qword_t *ev)
{
+ struct efx_nic *efx = channel->efx;
+ struct efx_ptp_data *ptp = efx->ptp_data;
+
+ /* When extracting the sync timestamp minor value, we should discard
+ * the least significant two bits. These are not required in order
+ * to reconstruct full-range timestamps and they are optionally used
+ * to report status depending on the options supplied when subscribing
+ * for sync events.
+ */
channel->sync_timestamp_major = MCDI_EVENT_FIELD(*ev, PTP_TIME_MAJOR);
channel->sync_timestamp_minor =
- MCDI_EVENT_FIELD(*ev, PTP_TIME_MINOR_26_19) << 19;
+ (MCDI_EVENT_FIELD(*ev, PTP_TIME_MINOR_MS_8BITS) & 0xFC)
+ << ptp->nic_time.sync_event_minor_shift;
+
/* if sync events have been disabled then we want to silently ignore
* this event, so throw away result.
*/
@@ -1865,15 +1942,6 @@ void efx_time_sync_event(struct efx_channel *channel, efx_qword_t *ev)
SYNC_EVENTS_VALID);
}
-/* make some assumptions about the time representation rather than abstract it,
- * since we currently only support one type of inline timestamping and only on
- * EF10.
- */
-#define MINOR_TICKS_PER_SECOND 0x8000000
-/* Fuzz factor for sync events to be out of order with RX events */
-#define FUZZ (MINOR_TICKS_PER_SECOND / 10)
-#define EXPECTED_SYNC_EVENTS_PER_SECOND 4
-
static inline u32 efx_rx_buf_timestamp_minor(struct efx_nic *efx, const u8 *eh)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
@@ -1891,28 +1959,33 @@ void __efx_rx_skb_attach_timestamp(struct efx_channel *channel,
struct sk_buff *skb)
{
struct efx_nic *efx = channel->efx;
+ struct efx_ptp_data *ptp = efx->ptp_data;
u32 pkt_timestamp_major, pkt_timestamp_minor;
u32 diff, carry;
struct skb_shared_hwtstamps *timestamps;
+ if (channel->sync_events_state != SYNC_EVENTS_VALID)
+ return;
+
pkt_timestamp_minor = efx_rx_buf_timestamp_minor(efx, skb_mac_header(skb));
/* get the difference between the packet and sync timestamps,
* modulo one second
*/
- diff = (pkt_timestamp_minor - channel->sync_timestamp_minor) &
- (MINOR_TICKS_PER_SECOND - 1);
+ diff = pkt_timestamp_minor - channel->sync_timestamp_minor;
+ if (pkt_timestamp_minor < channel->sync_timestamp_minor)
+ diff += ptp->nic_time.minor_max;
+
/* do we roll over a second boundary and need to carry the one? */
- carry = channel->sync_timestamp_minor + diff > MINOR_TICKS_PER_SECOND ?
+ carry = (channel->sync_timestamp_minor >= ptp->nic_time.minor_max - diff) ?
1 : 0;
- if (diff <= MINOR_TICKS_PER_SECOND / EXPECTED_SYNC_EVENTS_PER_SECOND +
- FUZZ) {
+ if (diff <= ptp->nic_time.sync_event_diff_max) {
/* packet is ahead of the sync event by a quarter of a second or
* less (allowing for fuzz)
*/
pkt_timestamp_major = channel->sync_timestamp_major + carry;
- } else if (diff >= MINOR_TICKS_PER_SECOND - FUZZ) {
+ } else if (diff >= ptp->nic_time.sync_event_diff_min) {
/* packet is behind the sync event but within the fuzz factor.
* This means the RX packet and sync event crossed as they were
* placed on the event queue, which can sometimes happen.
@@ -1933,10 +2006,10 @@ void __efx_rx_skb_attach_timestamp(struct efx_channel *channel,
/* attach the timestamps to the skb */
timestamps = skb_hwtstamps(skb);
- timestamps->hwtstamp = efx_ptp_s27_to_ktime_correction(
- pkt_timestamp_major,
- pkt_timestamp_minor,
- efx->ptp_data->ts_corrections.general_rx);
+ timestamps->hwtstamp =
+ ptp->nic_to_kernel_time(pkt_timestamp_major,
+ pkt_timestamp_minor,
+ ptp->ts_corrections.general_rx);
}
static int efx_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta)