From 47ed985e97f513b7746270e8c5d1f3a3f959b2da Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Sat, 8 Jun 2019 15:04:35 +0300 Subject: [PATCH] net: dsa: sja1105: Add logic for TX timestamping On TX, timestamping is performed synchronously from the port_deferred_xmit worker thread. In management routes, the switch is requested to take egress timestamps (again partial), which are reconstructed and appended to a clone of the skb that was just sent. The cloning is done by DSA and we retrieve the pointer from the structure that DSA keeps in skb->cb. Then these clones are enqueued to the socket's error queue for application-level processing. Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller --- drivers/net/dsa/sja1105/sja1105.h | 10 +++ drivers/net/dsa/sja1105/sja1105_main.c | 55 ++++++++++++- drivers/net/dsa/sja1105/sja1105_ptp.c | 106 +++++++++++++++++++++++++ drivers/net/dsa/sja1105/sja1105_ptp.h | 17 ++++ drivers/net/dsa/sja1105/sja1105_spi.c | 14 ++++ include/linux/dsa/sja1105.h | 1 + 6 files changed, 201 insertions(+), 2 deletions(-) diff --git a/drivers/net/dsa/sja1105/sja1105.h b/drivers/net/dsa/sja1105/sja1105.h index 3c6296203c21..5a4f83a3417b 100644 --- a/drivers/net/dsa/sja1105/sja1105.h +++ b/drivers/net/dsa/sja1105/sja1105.h @@ -33,6 +33,7 @@ struct sja1105_regs { u64 ptpclk; u64 ptpclkrate; u64 ptptsclk; + u64 ptpegr_ts[SJA1105_NUM_PORTS]; u64 pad_mii_tx[SJA1105_NUM_PORTS]; u64 cgu_idiv[SJA1105_NUM_PORTS]; u64 rgmii_pad_mii_tx[SJA1105_NUM_PORTS]; @@ -56,6 +57,15 @@ struct sja1105_info { * switch core and device_id) */ u64 part_no; + /* E/T and P/Q/R/S have partial timestamps of different sizes. + * They must be reconstructed on both families anyway to get the full + * 64-bit values back. + */ + int ptp_ts_bits; + /* Also SPI commands are of different sizes to retrieve + * the egress timestamps. + */ + int ptpegr_ts_bytes; const struct sja1105_dynamic_table_ops *dyn_ops; const struct sja1105_table_ops *static_ops; const struct sja1105_regs *regs; diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c index f897fdb12930..121ceccd8107 100644 --- a/drivers/net/dsa/sja1105/sja1105_main.c +++ b/drivers/net/dsa/sja1105/sja1105_main.c @@ -1565,7 +1565,7 @@ static int sja1105_setup(struct dsa_switch *ds) } static int sja1105_mgmt_xmit(struct dsa_switch *ds, int port, int slot, - struct sk_buff *skb) + struct sk_buff *skb, bool takets) { struct sja1105_mgmt_entry mgmt_route = {0}; struct sja1105_private *priv = ds->priv; @@ -1578,6 +1578,8 @@ static int sja1105_mgmt_xmit(struct dsa_switch *ds, int port, int slot, mgmt_route.macaddr = ether_addr_to_u64(hdr->h_dest); mgmt_route.destports = BIT(port); mgmt_route.enfport = 1; + mgmt_route.tsreg = 0; + mgmt_route.takets = takets; rc = sja1105_dynamic_config_write(priv, BLK_IDX_MGMT_ROUTE, slot, &mgmt_route, true); @@ -1629,7 +1631,11 @@ static netdev_tx_t sja1105_port_deferred_xmit(struct dsa_switch *ds, int port, { struct sja1105_private *priv = ds->priv; struct sja1105_port *sp = &priv->ports[port]; + struct skb_shared_hwtstamps shwt = {0}; int slot = sp->mgmt_slot; + struct sk_buff *clone; + u64 now, ts; + int rc; /* The tragic fact about the switch having 4x2 slots for installing * management routes is that all of them except one are actually @@ -1647,8 +1653,36 @@ static netdev_tx_t sja1105_port_deferred_xmit(struct dsa_switch *ds, int port, */ mutex_lock(&priv->mgmt_lock); - sja1105_mgmt_xmit(ds, port, slot, skb); + /* The clone, if there, was made by dsa_skb_tx_timestamp */ + clone = DSA_SKB_CB(skb)->clone; + + sja1105_mgmt_xmit(ds, port, slot, skb, !!clone); + + if (!clone) + goto out; + + skb_shinfo(clone)->tx_flags |= SKBTX_IN_PROGRESS; + + mutex_lock(&priv->ptp_lock); + + now = priv->tstamp_cc.read(&priv->tstamp_cc); + + rc = sja1105_ptpegr_ts_poll(priv, slot, &ts); + if (rc < 0) { + dev_err(ds->dev, "xmit: timed out polling for tstamp\n"); + kfree_skb(clone); + goto out_unlock_ptp; + } + + ts = sja1105_tstamp_reconstruct(priv, now, ts); + ts = timecounter_cyc2time(&priv->tstamp_tc, ts); + shwt.hwtstamp = ns_to_ktime(ts); + skb_complete_tx_timestamp(clone, &shwt); + +out_unlock_ptp: + mutex_unlock(&priv->ptp_lock); +out: mutex_unlock(&priv->mgmt_lock); return NETDEV_TX_OK; } @@ -1677,6 +1711,22 @@ static int sja1105_set_ageing_time(struct dsa_switch *ds, return sja1105_static_config_reload(priv); } +/* Called from dsa_skb_tx_timestamp. This callback is just to make DSA clone + * the skb and have it available in DSA_SKB_CB in the .port_deferred_xmit + * callback, where we will timestamp it synchronously. + */ +bool sja1105_port_txtstamp(struct dsa_switch *ds, int port, + struct sk_buff *skb, unsigned int type) +{ + struct sja1105_private *priv = ds->priv; + struct sja1105_port *sp = &priv->ports[port]; + + if (!sp->hwts_tx_en) + return false; + + return true; +} + static const struct dsa_switch_ops sja1105_switch_ops = { .get_tag_protocol = sja1105_get_tag_protocol, .setup = sja1105_setup, @@ -1701,6 +1751,7 @@ static const struct dsa_switch_ops sja1105_switch_ops = { .port_mdb_add = sja1105_mdb_add, .port_mdb_del = sja1105_mdb_del, .port_deferred_xmit = sja1105_port_deferred_xmit, + .port_txtstamp = sja1105_port_txtstamp, }; static int sja1105_check_device_id(struct sja1105_private *priv) diff --git a/drivers/net/dsa/sja1105/sja1105_ptp.c b/drivers/net/dsa/sja1105/sja1105_ptp.c index 47313a6ec932..01ecc8fb1b30 100644 --- a/drivers/net/dsa/sja1105/sja1105_ptp.c +++ b/drivers/net/dsa/sja1105/sja1105_ptp.c @@ -113,6 +113,112 @@ int sja1105pqrs_ptp_cmd(const void *ctx, const void *data) } EXPORT_SYMBOL_GPL(sja1105pqrs_ptp_cmd); +/* The switch returns partial timestamps (24 bits for SJA1105 E/T, which wrap + * around in 0.135 seconds, and 32 bits for P/Q/R/S, wrapping around in 34.35 + * seconds). + * + * This receives the RX or TX MAC timestamps, provided by hardware as + * the lower bits of the cycle counter, sampled at the time the timestamp was + * collected. + * + * To reconstruct into a full 64-bit-wide timestamp, the cycle counter is + * read and the high-order bits are filled in. + * + * Must be called within one wraparound period of the partial timestamp since + * it was generated by the MAC. + */ +u64 sja1105_tstamp_reconstruct(struct sja1105_private *priv, u64 now, + u64 ts_partial) +{ + u64 partial_tstamp_mask = CYCLECOUNTER_MASK(priv->info->ptp_ts_bits); + u64 ts_reconstructed; + + ts_reconstructed = (now & ~partial_tstamp_mask) | ts_partial; + + /* Check lower bits of current cycle counter against the timestamp. + * If the current cycle counter is lower than the partial timestamp, + * then wraparound surely occurred and must be accounted for. + */ + if ((now & partial_tstamp_mask) <= ts_partial) + ts_reconstructed -= (partial_tstamp_mask + 1); + + return ts_reconstructed; +} +EXPORT_SYMBOL_GPL(sja1105_tstamp_reconstruct); + +/* Reads the SPI interface for an egress timestamp generated by the switch + * for frames sent using management routes. + * + * SJA1105 E/T layout of the 4-byte SPI payload: + * + * 31 23 15 7 0 + * | | | | | + * +-----+-----+-----+ ^ + * ^ | + * | | + * 24-bit timestamp Update bit + * + * + * SJA1105 P/Q/R/S layout of the 8-byte SPI payload: + * + * 31 23 15 7 0 63 55 47 39 32 + * | | | | | | | | | | + * ^ +-----+-----+-----+-----+ + * | ^ + * | | + * Update bit 32-bit timestamp + * + * Notice that the update bit is in the same place. + * To have common code for E/T and P/Q/R/S for reading the timestamp, + * we need to juggle with the offset and the bit indices. + */ +int sja1105_ptpegr_ts_poll(struct sja1105_private *priv, int port, u64 *ts) +{ + const struct sja1105_regs *regs = priv->info->regs; + int tstamp_bit_start, tstamp_bit_end; + int timeout = 10; + u8 packed_buf[8]; + u64 update; + int rc; + + do { + rc = sja1105_spi_send_packed_buf(priv, SPI_READ, + regs->ptpegr_ts[port], + packed_buf, + priv->info->ptpegr_ts_bytes); + if (rc < 0) + return rc; + + sja1105_unpack(packed_buf, &update, 0, 0, + priv->info->ptpegr_ts_bytes); + if (update) + break; + + usleep_range(10, 50); + } while (--timeout); + + if (!timeout) + return -ETIMEDOUT; + + /* Point the end bit to the second 32-bit word on P/Q/R/S, + * no-op on E/T. + */ + tstamp_bit_end = (priv->info->ptpegr_ts_bytes - 4) * 8; + /* Shift the 24-bit timestamp on E/T to be collected from 31:8. + * No-op on P/Q/R/S. + */ + tstamp_bit_end += 32 - priv->info->ptp_ts_bits; + tstamp_bit_start = tstamp_bit_end + priv->info->ptp_ts_bits - 1; + + *ts = 0; + + sja1105_unpack(packed_buf, ts, tstamp_bit_start, tstamp_bit_end, + priv->info->ptpegr_ts_bytes); + + return 0; +} +EXPORT_SYMBOL_GPL(sja1105_ptpegr_ts_poll); + int sja1105_ptp_reset(struct sja1105_private *priv) { struct dsa_switch *ds = priv->ds; diff --git a/drivers/net/dsa/sja1105/sja1105_ptp.h b/drivers/net/dsa/sja1105/sja1105_ptp.h index 137ffbb0a233..af456b0a4d27 100644 --- a/drivers/net/dsa/sja1105/sja1105_ptp.h +++ b/drivers/net/dsa/sja1105/sja1105_ptp.h @@ -10,6 +10,8 @@ int sja1105_ptp_clock_register(struct sja1105_private *priv); void sja1105_ptp_clock_unregister(struct sja1105_private *priv); +int sja1105_ptpegr_ts_poll(struct sja1105_private *priv, int port, u64 *ts); + int sja1105et_ptp_cmd(const void *ctx, const void *data); int sja1105pqrs_ptp_cmd(const void *ctx, const void *data); @@ -17,6 +19,9 @@ int sja1105pqrs_ptp_cmd(const void *ctx, const void *data); int sja1105_get_ts_info(struct dsa_switch *ds, int port, struct ethtool_ts_info *ts); +u64 sja1105_tstamp_reconstruct(struct sja1105_private *priv, u64 now, + u64 ts_partial); + int sja1105_ptp_reset(struct sja1105_private *priv); #else @@ -31,6 +36,18 @@ static inline void sja1105_ptp_clock_unregister(struct sja1105_private *priv) return; } +static inline int +sja1105_ptpegr_ts_poll(struct sja1105_private *priv, int port, u64 *ts) +{ + return 0; +} + +static inline u64 sja1105_tstamp_reconstruct(struct sja1105_private *priv, + u64 now, u64 ts_partial) +{ + return 0; +} + static inline int sja1105_ptp_reset(struct sja1105_private *priv) { return 0; diff --git a/drivers/net/dsa/sja1105/sja1105_spi.c b/drivers/net/dsa/sja1105/sja1105_spi.c index a0d08e6c22ff..d729a0f0b28e 100644 --- a/drivers/net/dsa/sja1105/sja1105_spi.c +++ b/drivers/net/dsa/sja1105/sja1105_spi.c @@ -514,6 +514,7 @@ static struct sja1105_regs sja1105et_regs = { .rgmii_tx_clk = {0x100016, 0x10001D, 0x100024, 0x10002B, 0x100032}, .rmii_ref_clk = {0x100015, 0x10001C, 0x100023, 0x10002A, 0x100031}, .rmii_ext_tx_clk = {0x100018, 0x10001F, 0x100026, 0x10002D, 0x100034}, + .ptpegr_ts = {0xC0, 0xC2, 0xC4, 0xC6, 0xC8}, .ptp_control = 0x17, .ptpclk = 0x18, /* Spans 0x18 to 0x19 */ .ptpclkrate = 0x1A, @@ -544,6 +545,7 @@ static struct sja1105_regs sja1105pqrs_regs = { .rmii_ref_clk = {0x100015, 0x10001B, 0x100021, 0x100027, 0x10002D}, .rmii_ext_tx_clk = {0x100017, 0x10001D, 0x100023, 0x100029, 0x10002F}, .qlevel = {0x604, 0x614, 0x624, 0x634, 0x644}, + .ptpegr_ts = {0xC0, 0xC4, 0xC8, 0xCC, 0xD0}, .ptp_control = 0x18, .ptpclk = 0x19, .ptpclkrate = 0x1B, @@ -555,6 +557,8 @@ struct sja1105_info sja1105e_info = { .part_no = SJA1105ET_PART_NO, .static_ops = sja1105e_table_ops, .dyn_ops = sja1105et_dyn_ops, + .ptp_ts_bits = 24, + .ptpegr_ts_bytes = 4, .reset_cmd = sja1105et_reset_cmd, .fdb_add_cmd = sja1105et_fdb_add, .fdb_del_cmd = sja1105et_fdb_del, @@ -567,6 +571,8 @@ struct sja1105_info sja1105t_info = { .part_no = SJA1105ET_PART_NO, .static_ops = sja1105t_table_ops, .dyn_ops = sja1105et_dyn_ops, + .ptp_ts_bits = 24, + .ptpegr_ts_bytes = 4, .reset_cmd = sja1105et_reset_cmd, .fdb_add_cmd = sja1105et_fdb_add, .fdb_del_cmd = sja1105et_fdb_del, @@ -579,6 +585,8 @@ struct sja1105_info sja1105p_info = { .part_no = SJA1105P_PART_NO, .static_ops = sja1105p_table_ops, .dyn_ops = sja1105pqrs_dyn_ops, + .ptp_ts_bits = 32, + .ptpegr_ts_bytes = 8, .reset_cmd = sja1105pqrs_reset_cmd, .fdb_add_cmd = sja1105pqrs_fdb_add, .fdb_del_cmd = sja1105pqrs_fdb_del, @@ -591,6 +599,8 @@ struct sja1105_info sja1105q_info = { .part_no = SJA1105Q_PART_NO, .static_ops = sja1105q_table_ops, .dyn_ops = sja1105pqrs_dyn_ops, + .ptp_ts_bits = 32, + .ptpegr_ts_bytes = 8, .reset_cmd = sja1105pqrs_reset_cmd, .fdb_add_cmd = sja1105pqrs_fdb_add, .fdb_del_cmd = sja1105pqrs_fdb_del, @@ -603,6 +613,8 @@ struct sja1105_info sja1105r_info = { .part_no = SJA1105R_PART_NO, .static_ops = sja1105r_table_ops, .dyn_ops = sja1105pqrs_dyn_ops, + .ptp_ts_bits = 32, + .ptpegr_ts_bytes = 8, .reset_cmd = sja1105pqrs_reset_cmd, .fdb_add_cmd = sja1105pqrs_fdb_add, .fdb_del_cmd = sja1105pqrs_fdb_del, @@ -616,6 +628,8 @@ struct sja1105_info sja1105s_info = { .static_ops = sja1105s_table_ops, .dyn_ops = sja1105pqrs_dyn_ops, .regs = &sja1105pqrs_regs, + .ptp_ts_bits = 32, + .ptpegr_ts_bytes = 8, .reset_cmd = sja1105pqrs_reset_cmd, .fdb_add_cmd = sja1105pqrs_fdb_add, .fdb_del_cmd = sja1105pqrs_fdb_del, diff --git a/include/linux/dsa/sja1105.h b/include/linux/dsa/sja1105.h index e46e18c47d41..5a956f335022 100644 --- a/include/linux/dsa/sja1105.h +++ b/include/linux/dsa/sja1105.h @@ -22,6 +22,7 @@ struct sja1105_port { struct dsa_port *dp; + bool hwts_tx_en; int mgmt_slot; }; -- 2.30.2