diff options
author | Laurence Evans <levans@solarflare.com> | 2013-12-05 00:47:56 +0100 |
---|---|---|
committer | Ben Hutchings <bhutchings@solarflare.com> | 2013-12-12 23:07:09 +0100 |
commit | a6f73460b592404cca4ceafa69a835a61cdc20d8 (patch) | |
tree | e078025a329894bfc741c4a585597975ae5db87c /drivers | |
parent | sfc: Tidy up PTP synchronization code (diff) | |
download | linux-a6f73460b592404cca4ceafa69a835a61cdc20d8.tar.xz linux-a6f73460b592404cca4ceafa69a835a61cdc20d8.zip |
sfc: Add support for SFC9100 timestamp format
The clock minor tick on the SFC9100 family is 2^-27 s, not 1 ns.
There are also various pipeline delays which we need to correct for
when interpreting timestamps.
We query the firmware for the clock format and corrections at run-time.
[bwh: Combined and rebased several changes]
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/net/ethernet/sfc/ptp.c | 256 |
1 files changed, 231 insertions, 25 deletions
diff --git a/drivers/net/ethernet/sfc/ptp.c b/drivers/net/ethernet/sfc/ptp.c index 361d7cedd897..cf2ae11b13f1 100644 --- a/drivers/net/ethernet/sfc/ptp.c +++ b/drivers/net/ethernet/sfc/ptp.c @@ -62,7 +62,7 @@ #define SYNCHRONISATION_GRANULARITY_NS 200 /* Minimum permitted length of a (corrected) synchronisation time */ -#define MIN_SYNCHRONISATION_NS 120 +#define DEFAULT_MIN_SYNCHRONISATION_NS 120 /* Maximum permitted length of a (corrected) synchronisation time */ #define MAX_SYNCHRONISATION_NS 1000 @@ -195,20 +195,20 @@ struct efx_ptp_event_rx { /** * struct efx_ptp_timeset - Synchronisation between host and MC * @host_start: Host time immediately before hardware timestamp taken - * @seconds: Hardware timestamp, seconds - * @nanoseconds: Hardware timestamp, nanoseconds + * @major: Hardware timestamp, major + * @minor: Hardware timestamp, minor * @host_end: Host time immediately after hardware timestamp taken - * @waitns: Number of nanoseconds between hardware timestamp being read and + * @wait: Number of NIC clock ticks between hardware timestamp being read and * host end time being seen * @window: Difference of host_end and host_start * @valid: Whether this timeset is valid */ struct efx_ptp_timeset { u32 host_start; - u32 seconds; - u32 nanoseconds; + u32 major; + u32 minor; u32 host_end; - u32 waitns; + u32 wait; u32 window; /* Derived: end - start, allowing for wrap */ }; @@ -232,6 +232,14 @@ 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 + * @min_synchronisation_ns: Minimum acceptable corrected sync window + * @ts_corrections.tx: Required driver correction of transmit timestamps + * @ts_corrections.rx: Required driver correction of receive timestamps + * @ts_corrections.pps_out: PPS output error (information only) + * @ts_corrections.pps_in: Required driver correction of PPS input timestamps * @evt_frags: Partly assembled PTP events * @evt_frag_idx: Current fragment number * @evt_code: Last event code @@ -266,6 +274,17 @@ 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); + unsigned int min_synchronisation_ns; + struct { + s32 tx; + s32 rx; + s32 pps_out; + s32 pps_in; + } ts_corrections; efx_qword_t evt_frags[MAX_EVENT_FRAGS]; int evt_frag_idx; int evt_code; @@ -290,6 +309,167 @@ static int efx_phc_settime(struct ptp_clock_info *ptp, static int efx_phc_enable(struct ptp_clock_info *ptp, struct ptp_clock_request *request, int on); +/* For Siena platforms NIC time is s and ns */ +static void efx_ptp_ns_to_s_ns(s64 ns, u32 *nic_major, u32 *nic_minor) +{ + struct timespec ts = ns_to_timespec(ns); + *nic_major = ts.tv_sec; + *nic_minor = ts.tv_nsec; +} + +static ktime_t efx_ptp_s_ns_to_ktime(u32 nic_major, u32 nic_minor, + s32 correction) +{ + ktime_t 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; +} + +/* To convert from s27 format to ns we multiply then divide by a power of 2. + * For the conversion from ns to s27, the operation is also converted to a + * multiply and shift. + */ +#define S27_TO_NS_SHIFT (27) +#define NS_TO_S27_MULT (((1ULL << 63) + NSEC_PER_SEC / 2) / NSEC_PER_SEC) +#define NS_TO_S27_SHIFT (63 - S27_TO_NS_SHIFT) +#define S27_MINOR_MAX (1 << S27_TO_NS_SHIFT) + +/* For Huntington platforms NIC time is in seconds and fractions of a second + * where the minor register only uses 27 bits in units of 2^-27s. + */ +static void efx_ptp_ns_to_s27(s64 ns, u32 *nic_major, u32 *nic_minor) +{ + struct timespec ts = ns_to_timespec(ns); + u32 maj = ts.tv_sec; + u32 min = (u32)(((u64)ts.tv_nsec * NS_TO_S27_MULT + + (1ULL << (NS_TO_S27_SHIFT - 1))) >> NS_TO_S27_SHIFT); + + /* The conversion can result in the minor value exceeding the maximum. + * In this case, round up to the next second. + */ + if (min >= S27_MINOR_MAX) { + min -= S27_MINOR_MAX; + maj++; + } + + *nic_major = maj; + *nic_minor = min; +} + +static ktime_t efx_ptp_s27_to_ktime(u32 nic_major, u32 nic_minor, + s32 correction) +{ + u32 ns; + + /* Apply the correction and deal with carry */ + nic_minor += correction; + if ((s32)nic_minor < 0) { + nic_minor += S27_MINOR_MAX; + nic_major--; + } else if (nic_minor >= S27_MINOR_MAX) { + nic_minor -= S27_MINOR_MAX; + nic_major++; + } + + ns = (u32)(((u64)nic_minor * NSEC_PER_SEC + + (1ULL << (S27_TO_NS_SHIFT - 1))) >> S27_TO_NS_SHIFT); + + return ktime_set(nic_major, ns); +} + +/* Get PTP attributes and set up time conversions */ +static int efx_ptp_get_attributes(struct efx_nic *efx) +{ + MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_GET_ATTRIBUTES_LEN); + MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_GET_ATTRIBUTES_LEN); + struct efx_ptp_data *ptp = efx->ptp_data; + int rc; + u32 fmt; + size_t out_len; + + /* Get the PTP attributes. If the NIC doesn't support the operation we + * use the default format for compatibility with older NICs i.e. + * seconds and nanoseconds. + */ + MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_GET_ATTRIBUTES); + MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0); + rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf), + outbuf, sizeof(outbuf), &out_len); + if (rc == 0) + fmt = MCDI_DWORD(outbuf, PTP_OUT_GET_ATTRIBUTES_TIME_FORMAT); + else if (rc == -EINVAL) + fmt = MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_NANOSECONDS; + else + return rc; + + if (fmt == 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; + } else if (fmt == 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; + } else { + return -ERANGE; + } + + ptp->time_format = fmt; + + /* 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. + * 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) + ptp->min_synchronisation_ns = + MCDI_DWORD(outbuf, + PTP_OUT_GET_ATTRIBUTES_SYNC_WINDOW_MIN); + else + ptp->min_synchronisation_ns = DEFAULT_MIN_SYNCHRONISATION_NS; + + return 0; +} + +/* Get PTP timestamp corrections */ +static int efx_ptp_get_timestamp_corrections(struct efx_nic *efx) +{ + MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_GET_TIMESTAMP_CORRECTIONS_LEN); + MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_GET_TIMESTAMP_CORRECTIONS_LEN); + int rc; + + /* Get the timestamp corrections from the NIC. If this operation is + * not supported (older NICs) then no correction is required. + */ + MCDI_SET_DWORD(inbuf, PTP_IN_OP, + MC_CMD_PTP_OP_GET_TIMESTAMP_CORRECTIONS); + MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0); + + rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf), + outbuf, sizeof(outbuf), NULL); + if (rc == 0) { + efx->ptp_data->ts_corrections.tx = MCDI_DWORD(outbuf, + PTP_OUT_GET_TIMESTAMP_CORRECTIONS_TRANSMIT); + efx->ptp_data->ts_corrections.rx = MCDI_DWORD(outbuf, + PTP_OUT_GET_TIMESTAMP_CORRECTIONS_RECEIVE); + efx->ptp_data->ts_corrections.pps_out = MCDI_DWORD(outbuf, + PTP_OUT_GET_TIMESTAMP_CORRECTIONS_PPS_OUT); + efx->ptp_data->ts_corrections.pps_in = MCDI_DWORD(outbuf, + PTP_OUT_GET_TIMESTAMP_CORRECTIONS_PPS_IN); + } else if (rc == -EINVAL) { + efx->ptp_data->ts_corrections.tx = 0; + efx->ptp_data->ts_corrections.rx = 0; + efx->ptp_data->ts_corrections.pps_out = 0; + efx->ptp_data->ts_corrections.pps_in = 0; + } else { + return rc; + } + + return 0; +} + /* Enable MCDI PTP support. */ static int efx_ptp_enable(struct efx_nic *efx) { @@ -402,11 +582,10 @@ static void efx_ptp_read_timeset(MCDI_DECLARE_STRUCT_PTR(data), unsigned start_ns, end_ns; timeset->host_start = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTSTART); - timeset->seconds = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_SECONDS); - timeset->nanoseconds = MCDI_DWORD(data, - PTP_OUT_SYNCHRONIZE_NANOSECONDS); + timeset->major = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_MAJOR); + timeset->minor = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_MINOR); timeset->host_end = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTEND), - timeset->waitns = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_WAITNS); + timeset->wait = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_WAITNS); /* Ignore seconds */ start_ns = timeset->host_start & MC_NANOSECOND_MASK; @@ -441,6 +620,7 @@ efx_ptp_process_times(struct efx_nic *efx, MCDI_DECLARE_STRUCT_PTR(synch_buf), u32 last_sec; u32 start_sec; struct timespec delta; + ktime_t mc_time; if (number_readings == 0) return -EAGAIN; @@ -452,14 +632,17 @@ efx_ptp_process_times(struct efx_nic *efx, MCDI_DECLARE_STRUCT_PTR(synch_buf), */ for (i = 0; i < number_readings; i++) { s32 window, corrected; + struct timespec wait; efx_ptp_read_timeset( MCDI_ARRAY_STRUCT_PTR(synch_buf, PTP_OUT_SYNCHRONIZE_TIMESET, i), &ptp->timeset[i]); + wait = ktime_to_timespec( + ptp->nic_to_kernel_time(0, ptp->timeset[i].wait, 0)); window = ptp->timeset[i].window; - corrected = window - ptp->timeset[i].waitns; + corrected = window - wait.tv_nsec; /* We expect the uncorrected synchronization window to be at * least as large as the interval between host start and end @@ -472,7 +655,7 @@ efx_ptp_process_times(struct efx_nic *efx, MCDI_DECLARE_STRUCT_PTR(synch_buf), */ if (window >= SYNCHRONISATION_GRANULARITY_NS && corrected < MAX_SYNCHRONISATION_NS && - corrected >= MIN_SYNCHRONISATION_NS) { + corrected >= ptp->min_synchronisation_ns) { ngood++; last_good = i; } @@ -484,9 +667,15 @@ efx_ptp_process_times(struct efx_nic *efx, MCDI_DECLARE_STRUCT_PTR(synch_buf), return -EAGAIN; } + /* Convert the NIC time into kernel time. No correction is required- + * this time is the output of a firmware process. + */ + mc_time = ptp->nic_to_kernel_time(ptp->timeset[last_good].major, + ptp->timeset[last_good].minor, 0); + /* Calculate delay from actual PPS to last_time */ - delta.tv_nsec = - ptp->timeset[last_good].nanoseconds + + delta = ktime_to_timespec(mc_time); + delta.tv_nsec += last_time->ts_real.tv_nsec - (ptp->timeset[last_good].host_start & MC_NANOSECOND_MASK); @@ -596,9 +785,10 @@ static int efx_ptp_xmit_skb(struct efx_nic *efx, struct sk_buff *skb) goto fail; memset(×tamps, 0, sizeof(timestamps)); - timestamps.hwtstamp = ktime_set( - MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_SECONDS), - MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_NANOSECONDS)); + timestamps.hwtstamp = ptp_data->nic_to_kernel_time( + MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_MAJOR), + MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_MINOR), + ptp_data->ts_corrections.tx); skb_tstamp_tx(skb, ×tamps); @@ -954,6 +1144,16 @@ int efx_ptp_probe(struct efx_nic *efx, struct efx_channel *channel) list_add(&ptp->rx_evts[pos].link, &ptp->evt_free_list); ptp->evt_overflow = false; + /* Get the NIC PTP attributes and set up time conversions */ + rc = efx_ptp_get_attributes(efx); + if (rc < 0) + goto fail3; + + /* Get the timestamp corrections */ + rc = efx_ptp_get_timestamp_corrections(efx); + if (rc < 0) + goto fail3; + ptp->phc_clock_info = efx_phc_clock_info; ptp->phc_clock = ptp_clock_register(&ptp->phc_clock_info, &efx->pci_dev->dev); @@ -1358,9 +1558,10 @@ static void ptp_event_rx(struct efx_nic *efx, struct efx_ptp_data *ptp) MCDI_EVENT_SRC) << 8) | (EFX_QWORD_FIELD(ptp->evt_frags[0], MCDI_EVENT_SRC) << 16)); - evt->hwtimestamp = ktime_set( + evt->hwtimestamp = efx->ptp_data->nic_to_kernel_time( EFX_QWORD_FIELD(ptp->evt_frags[0], MCDI_EVENT_DATA), - EFX_QWORD_FIELD(ptp->evt_frags[1], MCDI_EVENT_DATA)); + EFX_QWORD_FIELD(ptp->evt_frags[1], MCDI_EVENT_DATA), + ptp->ts_corrections.rx); evt->expiry = jiffies + msecs_to_jiffies(PKT_EVENT_LIFETIME_MS); list_add_tail(&evt->link, &ptp->evt_list); @@ -1470,18 +1671,20 @@ static int efx_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta) static int efx_phc_adjtime(struct ptp_clock_info *ptp, s64 delta) { + u32 nic_major, nic_minor; struct efx_ptp_data *ptp_data = container_of(ptp, struct efx_ptp_data, phc_clock_info); struct efx_nic *efx = ptp_data->efx; - struct timespec delta_ts = ns_to_timespec(delta); MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_ADJUST_LEN); + efx->ptp_data->ns_to_nic_time(delta, &nic_major, &nic_minor); + MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_ADJUST); MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0); MCDI_SET_QWORD(inbuf, PTP_IN_ADJUST_FREQ, ptp_data->current_adjfreq); - MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_SECONDS, (u32)delta_ts.tv_sec); - MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_NANOSECONDS, (u32)delta_ts.tv_nsec); + MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_MAJOR, nic_major); + MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_MINOR, nic_minor); return efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf), NULL, 0, NULL); } @@ -1495,6 +1698,7 @@ static int efx_phc_gettime(struct ptp_clock_info *ptp, struct timespec *ts) MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_READ_NIC_TIME_LEN); MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_READ_NIC_TIME_LEN); int rc; + ktime_t kt; MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_READ_NIC_TIME); MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0); @@ -1504,8 +1708,10 @@ static int efx_phc_gettime(struct ptp_clock_info *ptp, struct timespec *ts) if (rc != 0) return rc; - ts->tv_sec = MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_SECONDS); - ts->tv_nsec = MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_NANOSECONDS); + kt = ptp_data->nic_to_kernel_time( + MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_MAJOR), + MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_MINOR), 0); + *ts = ktime_to_timespec(kt); return 0; } |