| Message ID | 20221014152857.32645-6-arun.ramadoss@microchip.com (mailing list archive) |
|---|---|
| State | RFC |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: dsa: microchip: add gPTP support for LAN937x switch | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Clearly marked for net-next |
| netdev/fixes_present | success | Fixes tag not required for -next series |
| netdev/subject_prefix | success | Link |
| netdev/cover_letter | success | Series has a cover letter |
| netdev/patch_count | success | Link |
| netdev/header_inline | success | No static functions without inline keyword in header files |
| netdev/build_32bit | fail | Errors and warnings before: 10 this patch: 11 |
| netdev/cc_maintainers | success | CCed 11 of 11 maintainers |
| netdev/build_clang | fail | Errors and warnings before: 10 this patch: 11 |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Signed-off-by tag matches author and committer |
| netdev/check_selftest | success | No net selftest shell script |
| netdev/verify_fixes | success | No Fixes tag |
| netdev/build_allmodconfig_warn | fail | Errors and warnings before: 10 this patch: 11 |
| netdev/checkpatch | warning | WARNING: line length of 83 exceeds 80 columns |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/source_inline | success | Was 0 now: 0 |
Hi Arun, On Friday, 14 October 2022, 17:28:56 CEST, Arun Ramadoss wrote: > This patch adds the routines for timestamping received ptp packets. > Whenever the ptp packet is received, the 4 byte hardware time stamped > value is append to its packet. This 4 byte value is extracted from the > tail tag and reconstructed to absolute time and assigned to skb > hwtstamp. > > Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com> > --- > drivers/net/dsa/microchip/ksz_common.c | 12 +++++++++++ > drivers/net/dsa/microchip/ksz_ptp.c | 25 +++++++++++++++++++++ > drivers/net/dsa/microchip/ksz_ptp.h | 6 ++++++ > include/linux/dsa/ksz_common.h | 15 +++++++++++++ > net/dsa/tag_ksz.c | 30 ++++++++++++++++++++++---- > 5 files changed, 84 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c > index 0c0fdb7b7879..388731959b23 100644 > --- a/drivers/net/dsa/microchip/ksz_common.c > +++ b/drivers/net/dsa/microchip/ksz_common.c > @@ -2426,6 +2426,17 @@ static enum dsa_tag_protocol ksz_get_tag_protocol(struct dsa_switch *ds, > return proto; > } > > +static int ksz_connect_tag_protocol(struct dsa_switch *ds, > + enum dsa_tag_protocol proto) > +{ > + struct ksz_tagger_data *tagger_data; > + > + tagger_data = ksz_tagger_data(ds); NULL pointer dereference is here: ksz_connect() is only called for "lan937x", not for the other KSZ switches. If ksz_connect() shall only be called for PTP switches, the result of ksz_tagger_data() may be NULL. > + tagger_data->meta_tstamp_handler = ksz_tstamp_reconstruct; > + > + return 0; > +} > + > static int ksz_port_vlan_filtering(struct dsa_switch *ds, int port, > bool flag, struct netlink_ext_ack *extack) > { > @@ -2819,6 +2830,7 @@ static int ksz_switch_detect(struct ksz_device *dev) > > static const struct dsa_switch_ops ksz_switch_ops = { > .get_tag_protocol = ksz_get_tag_protocol, > + .connect_tag_protocol = ksz_connect_tag_protocol, > .get_phy_flags = ksz_get_phy_flags, > .setup = ksz_setup, > .teardown = ksz_teardown, > diff --git a/drivers/net/dsa/microchip/ksz_ptp.c b/drivers/net/dsa/microchip/ksz_ptp.c > index 2cae543f7e0b..5ae6eedb6b39 100644 > --- a/drivers/net/dsa/microchip/ksz_ptp.c > +++ b/drivers/net/dsa/microchip/ksz_ptp.c > @@ -372,6 +372,31 @@ static int ksz_ptp_start_clock(struct ksz_device *dev) > return 0; > } > > +ktime_t ksz_tstamp_reconstruct(struct dsa_switch *ds, ktime_t tstamp) > +{ > + struct ksz_device *dev = ds->priv; > + struct ksz_ptp_data *ptp_data = &dev->ptp_data; > + struct timespec64 ts = ktime_to_timespec64(tstamp); > + struct timespec64 ptp_clock_time; > + struct timespec64 diff; > + > + spin_lock_bh(&ptp_data->clock_lock); > + ptp_clock_time = ptp_data->clock_time; > + spin_unlock_bh(&ptp_data->clock_lock); > + > + /* calculate full time from partial time stamp */ > + ts.tv_sec = (ptp_clock_time.tv_sec & ~3) | ts.tv_sec; > + > + /* find nearest possible point in time */ > + diff = timespec64_sub(ts, ptp_clock_time); > + if (diff.tv_sec > 2) > + ts.tv_sec -= 4; > + else if (diff.tv_sec < -2) > + ts.tv_sec += 4; > + > + return timespec64_to_ktime(ts); > +} > + > static const struct ptp_clock_info ksz_ptp_caps = { > .owner = THIS_MODULE, > .name = "Microchip Clock", > diff --git a/drivers/net/dsa/microchip/ksz_ptp.h b/drivers/net/dsa/microchip/ksz_ptp.h > index 7e5d374d2acf..9589909ab7d5 100644 > --- a/drivers/net/dsa/microchip/ksz_ptp.h > +++ b/drivers/net/dsa/microchip/ksz_ptp.h > @@ -28,6 +28,7 @@ int ksz_hwtstamp_get(struct dsa_switch *ds, int port, struct ifreq *ifr); > int ksz_hwtstamp_set(struct dsa_switch *ds, int port, struct ifreq *ifr); > int ksz_ptp_irq_setup(struct dsa_switch *ds, u8 p); > void ksz_ptp_irq_free(struct dsa_switch *ds, u8 p); > +ktime_t ksz_tstamp_reconstruct(struct dsa_switch *ds, ktime_t tstamp); > > #else > > @@ -64,6 +65,11 @@ static inline int ksz_ptp_irq_setup(struct dsa_switch *ds, u8 p) > > static inline void ksz_ptp_irq_free(struct dsa_switch *ds, u8 p) {} > > +static inline ktime_t ksz_tstamp_reconstruct(struct dsa_switch *ds, ktime_t tstamp) > +{ > + return 0; > +} > + > #endif /* End of CONFIG_NET_DSA_MICROCHIOP_KSZ_PTP */ > > #endif > diff --git a/include/linux/dsa/ksz_common.h b/include/linux/dsa/ksz_common.h > index 8903bce4753b..82edd7228b3c 100644 > --- a/include/linux/dsa/ksz_common.h > +++ b/include/linux/dsa/ksz_common.h > @@ -9,9 +9,24 @@ > > #include <net/dsa.h> > > +/* All time stamps from the KSZ consist of 2 bits for seconds and 30 bits for > + * nanoseconds. This is NOT the same as 32 bits for nanoseconds. > + */ > +#define KSZ_TSTAMP_SEC_MASK GENMASK(31, 30) > +#define KSZ_TSTAMP_NSEC_MASK GENMASK(29, 0) > + > +static inline ktime_t ksz_decode_tstamp(u32 tstamp) > +{ > + u64 ns = FIELD_GET(KSZ_TSTAMP_SEC_MASK, tstamp) * NSEC_PER_SEC + > + FIELD_GET(KSZ_TSTAMP_NSEC_MASK, tstamp); > + > + return ns_to_ktime(ns); > +} > + > struct ksz_tagger_data { > bool (*hwtstamp_get_state)(struct dsa_switch *ds); > void (*hwtstamp_set_state)(struct dsa_switch *ds, bool on); > + ktime_t (*meta_tstamp_handler)(struct dsa_switch *ds, ktime_t tstamp); > }; > > static inline struct ksz_tagger_data * > diff --git a/net/dsa/tag_ksz.c b/net/dsa/tag_ksz.c > index ca1261b04fe7..937a3e70b471 100644 > --- a/net/dsa/tag_ksz.c > +++ b/net/dsa/tag_ksz.c > @@ -164,6 +164,25 @@ MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795); > #define KSZ9477_TAIL_TAG_OVERRIDE BIT(9) > #define KSZ9477_TAIL_TAG_LOOKUP BIT(10) > > +static void ksz_rcv_timestamp(struct sk_buff *skb, u8 *tag, > + struct net_device *dev, unsigned int port) > +{ > + struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); > + u8 *tstamp_raw = tag - KSZ9477_PTP_TAG_LEN; > + struct dsa_switch *ds = dev->dsa_ptr->ds; > + struct ksz_tagger_data *tagger_data; > + ktime_t tstamp; > + > + tagger_data = ksz_tagger_data(ds); another potential NULL pointer dereference here: > + if (!tagger_data->meta_tstamp_handler) > + return; > + > + /* convert time stamp and write to skb */ > + tstamp = ksz_decode_tstamp(get_unaligned_be32(tstamp_raw)); > + memset(hwtstamps, 0, sizeof(*hwtstamps)); > + hwtstamps->hwtstamp = tagger_data->meta_tstamp_handler(ds, tstamp); > +} > + > static struct sk_buff *ksz9477_xmit(struct sk_buff *skb, > struct net_device *dev) > { > @@ -197,8 +216,10 @@ static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev) > unsigned int len = KSZ_EGRESS_TAG_LEN; > > /* Extra 4-bytes PTP timestamp */ > - if (tag[0] & KSZ9477_PTP_TAG_INDICATION) > + if (tag[0] & KSZ9477_PTP_TAG_INDICATION) { > + ksz_rcv_timestamp(skb, tag, dev, port); > len += KSZ9477_PTP_TAG_LEN; > + } > > return ksz_common_rcv(skb, dev, port, len); > } > @@ -257,10 +278,11 @@ MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893); > * tag0 : represents tag override, lookup and valid > * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x80=port8) > * > - * For rcv, 1 byte is added before FCS. > + * For rcv, 1/5 bytes is added before FCS. > * --------------------------------------------------------------------------- > - * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes) > + * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes) > * --------------------------------------------------------------------------- > + * ts : time stamp (Present only if bit 7 of tag0 is set) > * tag0 : zero-based value represents port > * (eg, 0x00=port1, 0x02=port3, 0x07=port8) > */ > @@ -304,7 +326,7 @@ static const struct dsa_device_ops lan937x_netdev_ops = { > .rcv = ksz9477_rcv, > .connect = ksz_connect, > .disconnect = ksz_disconnect, > - .needed_tailroom = LAN937X_EGRESS_TAG_LEN, > + .needed_tailroom = LAN937X_EGRESS_TAG_LEN + KSZ9477_PTP_TAG_LEN, > }; > > DSA_TAG_DRIVER(lan937x_netdev_ops); >
On Tue, Oct 25, 2022 at 08:17:37AM +0200, Christian Eggers wrote: > > +static int ksz_connect_tag_protocol(struct dsa_switch *ds, > > + enum dsa_tag_protocol proto) > > +{ > > + struct ksz_tagger_data *tagger_data; > > + > > + tagger_data = ksz_tagger_data(ds); > > NULL pointer dereference is here: > > ksz_connect() is only called for "lan937x", not for the other KSZ switches. > If ksz_connect() shall only be called for PTP switches, the result of > ksz_tagger_data() may be NULL. > > > + tagger_data->meta_tstamp_handler = ksz_tstamp_reconstruct; > > + > > + return 0; > > +} > > + The observation is correct. All other drivers which use this API check the protocol given as argument, and for good reason. Only "lan937x" allocates tagger-owned storage in Arun's implementation, but the common ksz library supports more tagging protocols.
diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c index 0c0fdb7b7879..388731959b23 100644 --- a/drivers/net/dsa/microchip/ksz_common.c +++ b/drivers/net/dsa/microchip/ksz_common.c @@ -2426,6 +2426,17 @@ static enum dsa_tag_protocol ksz_get_tag_protocol(struct dsa_switch *ds, return proto; } +static int ksz_connect_tag_protocol(struct dsa_switch *ds, + enum dsa_tag_protocol proto) +{ + struct ksz_tagger_data *tagger_data; + + tagger_data = ksz_tagger_data(ds); + tagger_data->meta_tstamp_handler = ksz_tstamp_reconstruct; + + return 0; +} + static int ksz_port_vlan_filtering(struct dsa_switch *ds, int port, bool flag, struct netlink_ext_ack *extack) { @@ -2819,6 +2830,7 @@ static int ksz_switch_detect(struct ksz_device *dev) static const struct dsa_switch_ops ksz_switch_ops = { .get_tag_protocol = ksz_get_tag_protocol, + .connect_tag_protocol = ksz_connect_tag_protocol, .get_phy_flags = ksz_get_phy_flags, .setup = ksz_setup, .teardown = ksz_teardown, diff --git a/drivers/net/dsa/microchip/ksz_ptp.c b/drivers/net/dsa/microchip/ksz_ptp.c index 2cae543f7e0b..5ae6eedb6b39 100644 --- a/drivers/net/dsa/microchip/ksz_ptp.c +++ b/drivers/net/dsa/microchip/ksz_ptp.c @@ -372,6 +372,31 @@ static int ksz_ptp_start_clock(struct ksz_device *dev) return 0; } +ktime_t ksz_tstamp_reconstruct(struct dsa_switch *ds, ktime_t tstamp) +{ + struct ksz_device *dev = ds->priv; + struct ksz_ptp_data *ptp_data = &dev->ptp_data; + struct timespec64 ts = ktime_to_timespec64(tstamp); + struct timespec64 ptp_clock_time; + struct timespec64 diff; + + spin_lock_bh(&ptp_data->clock_lock); + ptp_clock_time = ptp_data->clock_time; + spin_unlock_bh(&ptp_data->clock_lock); + + /* calculate full time from partial time stamp */ + ts.tv_sec = (ptp_clock_time.tv_sec & ~3) | ts.tv_sec; + + /* find nearest possible point in time */ + diff = timespec64_sub(ts, ptp_clock_time); + if (diff.tv_sec > 2) + ts.tv_sec -= 4; + else if (diff.tv_sec < -2) + ts.tv_sec += 4; + + return timespec64_to_ktime(ts); +} + static const struct ptp_clock_info ksz_ptp_caps = { .owner = THIS_MODULE, .name = "Microchip Clock", diff --git a/drivers/net/dsa/microchip/ksz_ptp.h b/drivers/net/dsa/microchip/ksz_ptp.h index 7e5d374d2acf..9589909ab7d5 100644 --- a/drivers/net/dsa/microchip/ksz_ptp.h +++ b/drivers/net/dsa/microchip/ksz_ptp.h @@ -28,6 +28,7 @@ int ksz_hwtstamp_get(struct dsa_switch *ds, int port, struct ifreq *ifr); int ksz_hwtstamp_set(struct dsa_switch *ds, int port, struct ifreq *ifr); int ksz_ptp_irq_setup(struct dsa_switch *ds, u8 p); void ksz_ptp_irq_free(struct dsa_switch *ds, u8 p); +ktime_t ksz_tstamp_reconstruct(struct dsa_switch *ds, ktime_t tstamp); #else @@ -64,6 +65,11 @@ static inline int ksz_ptp_irq_setup(struct dsa_switch *ds, u8 p) static inline void ksz_ptp_irq_free(struct dsa_switch *ds, u8 p) {} +static inline ktime_t ksz_tstamp_reconstruct(struct dsa_switch *ds, ktime_t tstamp) +{ + return 0; +} + #endif /* End of CONFIG_NET_DSA_MICROCHIOP_KSZ_PTP */ #endif diff --git a/include/linux/dsa/ksz_common.h b/include/linux/dsa/ksz_common.h index 8903bce4753b..82edd7228b3c 100644 --- a/include/linux/dsa/ksz_common.h +++ b/include/linux/dsa/ksz_common.h @@ -9,9 +9,24 @@ #include <net/dsa.h> +/* All time stamps from the KSZ consist of 2 bits for seconds and 30 bits for + * nanoseconds. This is NOT the same as 32 bits for nanoseconds. + */ +#define KSZ_TSTAMP_SEC_MASK GENMASK(31, 30) +#define KSZ_TSTAMP_NSEC_MASK GENMASK(29, 0) + +static inline ktime_t ksz_decode_tstamp(u32 tstamp) +{ + u64 ns = FIELD_GET(KSZ_TSTAMP_SEC_MASK, tstamp) * NSEC_PER_SEC + + FIELD_GET(KSZ_TSTAMP_NSEC_MASK, tstamp); + + return ns_to_ktime(ns); +} + struct ksz_tagger_data { bool (*hwtstamp_get_state)(struct dsa_switch *ds); void (*hwtstamp_set_state)(struct dsa_switch *ds, bool on); + ktime_t (*meta_tstamp_handler)(struct dsa_switch *ds, ktime_t tstamp); }; static inline struct ksz_tagger_data * diff --git a/net/dsa/tag_ksz.c b/net/dsa/tag_ksz.c index ca1261b04fe7..937a3e70b471 100644 --- a/net/dsa/tag_ksz.c +++ b/net/dsa/tag_ksz.c @@ -164,6 +164,25 @@ MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795); #define KSZ9477_TAIL_TAG_OVERRIDE BIT(9) #define KSZ9477_TAIL_TAG_LOOKUP BIT(10) +static void ksz_rcv_timestamp(struct sk_buff *skb, u8 *tag, + struct net_device *dev, unsigned int port) +{ + struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); + u8 *tstamp_raw = tag - KSZ9477_PTP_TAG_LEN; + struct dsa_switch *ds = dev->dsa_ptr->ds; + struct ksz_tagger_data *tagger_data; + ktime_t tstamp; + + tagger_data = ksz_tagger_data(ds); + if (!tagger_data->meta_tstamp_handler) + return; + + /* convert time stamp and write to skb */ + tstamp = ksz_decode_tstamp(get_unaligned_be32(tstamp_raw)); + memset(hwtstamps, 0, sizeof(*hwtstamps)); + hwtstamps->hwtstamp = tagger_data->meta_tstamp_handler(ds, tstamp); +} + static struct sk_buff *ksz9477_xmit(struct sk_buff *skb, struct net_device *dev) { @@ -197,8 +216,10 @@ static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev) unsigned int len = KSZ_EGRESS_TAG_LEN; /* Extra 4-bytes PTP timestamp */ - if (tag[0] & KSZ9477_PTP_TAG_INDICATION) + if (tag[0] & KSZ9477_PTP_TAG_INDICATION) { + ksz_rcv_timestamp(skb, tag, dev, port); len += KSZ9477_PTP_TAG_LEN; + } return ksz_common_rcv(skb, dev, port, len); } @@ -257,10 +278,11 @@ MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893); * tag0 : represents tag override, lookup and valid * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x80=port8) * - * For rcv, 1 byte is added before FCS. + * For rcv, 1/5 bytes is added before FCS. * --------------------------------------------------------------------------- - * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes) + * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes) * --------------------------------------------------------------------------- + * ts : time stamp (Present only if bit 7 of tag0 is set) * tag0 : zero-based value represents port * (eg, 0x00=port1, 0x02=port3, 0x07=port8) */ @@ -304,7 +326,7 @@ static const struct dsa_device_ops lan937x_netdev_ops = { .rcv = ksz9477_rcv, .connect = ksz_connect, .disconnect = ksz_disconnect, - .needed_tailroom = LAN937X_EGRESS_TAG_LEN, + .needed_tailroom = LAN937X_EGRESS_TAG_LEN + KSZ9477_PTP_TAG_LEN, }; DSA_TAG_DRIVER(lan937x_netdev_ops);
This patch adds the routines for timestamping received ptp packets. Whenever the ptp packet is received, the 4 byte hardware time stamped value is append to its packet. This 4 byte value is extracted from the tail tag and reconstructed to absolute time and assigned to skb hwtstamp. Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com> --- drivers/net/dsa/microchip/ksz_common.c | 12 +++++++++++ drivers/net/dsa/microchip/ksz_ptp.c | 25 +++++++++++++++++++++ drivers/net/dsa/microchip/ksz_ptp.h | 6 ++++++ include/linux/dsa/ksz_common.h | 15 +++++++++++++ net/dsa/tag_ksz.c | 30 ++++++++++++++++++++++---- 5 files changed, 84 insertions(+), 4 deletions(-)