On Fri, Apr 16, 2021 at 08:36:55PM +0800, Yangbo Lu wrote:
> Although HWTSTAMP_TX_ONESTEP_SYNC existed in ioctl for hardware timestamp
> configuration, the PTP Sync one-step timestamping had never been supported.
>
> This patch is to truely support it.
Actually the ocelot switchdev driver does support one-step timestamping,
just the felix DSA driver does not.
> The hardware timestamp request type is
> stored in DSA_SKB_CB_PRIV first byte per skb, so that corresponding
> configuration could be done during transmitting. Non-onestep-Sync packet
> with one-step timestamp request should fall back to use two-step timestamp.
>
> Signed-off-by: Yangbo Lu <yangbo.lu@xxxxxxx>
> ---
> drivers/net/ethernet/mscc/ocelot.c | 57 ++++++++++++++++++++++++++
> drivers/net/ethernet/mscc/ocelot_net.c | 5 +--
> include/soc/mscc/ocelot.h | 1 +
> net/dsa/tag_ocelot.c | 25 ++---------
> net/dsa/tag_ocelot_8021q.c | 39 +++++-------------
> 5 files changed, 72 insertions(+), 55 deletions(-)
>
> diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c
> index 541d3b4076be..69d36b6241ff 100644
> --- a/drivers/net/ethernet/mscc/ocelot.c
> +++ b/drivers/net/ethernet/mscc/ocelot.c
> @@ -6,6 +6,7 @@
> */
> #include <linux/dsa/ocelot.h>
> #include <linux/if_bridge.h>
> +#include <linux/ptp_classify.h>
> #include <soc/mscc/ocelot_vcap.h>
> #include "ocelot.h"
> #include "ocelot_vcap.h"
> @@ -546,6 +547,50 @@ static void ocelot_port_add_txtstamp_skb(struct ocelot *ocelot, int port,
> spin_unlock(&ocelot_port->ts_id_lock);
> }
>
> +bool ocelot_ptp_rew_op(struct sk_buff *skb, struct sk_buff *clone, u32 *rew_op)
> +{
> + /* For two-step timestamp, retrieve ptp_cmd in DSA_SKB_CB_PRIV
> + * and timestamp ID in clone->cb[0].
> + * For one-step timestamp, retrieve ptp_cmd in DSA_SKB_CB_PRIV.
> + */
> + u8 *ptp_cmd = DSA_SKB_CB_PRIV(skb);
This is fine in the sense that it works, but please consider creating
something similar to sja1105:
struct ocelot_skb_cb {
u8 ptp_cmd; /* For both one-step and two-step timestamping */
u8 ts_id; /* Only for two-step timestamping */
};
#define OCELOT_SKB_CB(skb) \
((struct ocelot_skb_cb *)DSA_SKB_CB_PRIV(skb))
And then access as OCELOT_SKB_CB(skb)->ptp_cmd, OCELOT_SKB_CB(clone)->ts_id.
and put a comment to explain that this is done in order to have common
code between Felix DSA and Ocelot switchdev. Basically Ocelot will not
use the first 8 bytes of skb->cb, but there's enough space for this to
not make any difference. The original skb will hold only ptp_cmd, the
clone will only hold ts_id, but it helps to have the same structure in
place.
If you create this ocelot_skb_cb structure, I expect the comment above
to be fairly redundant, you can consider removing it.
> +
> + if (clone) {
> + *rew_op = *ptp_cmd;
> + *rew_op |= clone->cb[0] << 3;
> + } else if (*ptp_cmd) {
> + *rew_op = *ptp_cmd;
> + } else {
> + return false;
> + }
> +
> + return true;
Just make this function return an u32. If the packet isn't PTP, the
rew_op will be 0.
> +}
> +EXPORT_SYMBOL(ocelot_ptp_rew_op);
> +
> +static bool ocelot_ptp_is_onestep_sync(struct sk_buff *skb)
> +{
> + struct ptp_header *hdr;
> + unsigned int ptp_class;
> + u8 msgtype, twostep;
> +
> + ptp_class = ptp_classify_raw(skb);
> + if (ptp_class == PTP_CLASS_NONE)
> + return false;
> +
> + hdr = ptp_parse_header(skb, ptp_class);
> + if (!hdr)
> + return false;
> +
> + msgtype = ptp_get_msgtype(hdr, ptp_class);
> + twostep = hdr->flag_field[0] & 0x2;
> +
> + if (msgtype == PTP_MSGTYPE_SYNC && twostep == 0)
> + return true;
> +
> + return false;
> +}
> +
This is generic, but if you were to move it to net/core/ptp_classifier.c,
I think you would have to pass the output of ptp_classify_raw() as an
"unsigned int type" argument. So I think I would leave it the way it is
for now - inside of ocelot - until somebody else needs something
similar, and we see what is the required prototype.
> int ocelot_port_txtstamp_request(struct ocelot *ocelot, int port,
> struct sk_buff *skb,
> struct sk_buff **clone)
> @@ -553,12 +598,24 @@ int ocelot_port_txtstamp_request(struct ocelot *ocelot, int port,
> struct ocelot_port *ocelot_port = ocelot->ports[port];
> u8 ptp_cmd = ocelot_port->ptp_cmd;
>
> + /* Store ptp_cmd in first byte of DSA_SKB_CB_PRIV per skb */
> + if (ptp_cmd == IFH_REW_OP_ORIGIN_PTP) {
> + if (ocelot_ptp_is_onestep_sync(skb)) {
> + *(u8 *)DSA_SKB_CB_PRIV(skb) = ptp_cmd;
> + return 0;
> + }
> +
> + /* Fall back to two-step timestamping */
> + ptp_cmd = IFH_REW_OP_TWO_STEP_PTP;
> + }
> +
> if (ptp_cmd == IFH_REW_OP_TWO_STEP_PTP) {
> *clone = skb_clone_sk(skb);
> if (!(*clone))
> return -ENOMEM;
>
> ocelot_port_add_txtstamp_skb(ocelot, port, *clone);
> + *(u8 *)DSA_SKB_CB_PRIV(skb) = ptp_cmd;
> }
>
> return 0;
> diff --git a/drivers/net/ethernet/mscc/ocelot_net.c b/drivers/net/ethernet/mscc/ocelot_net.c
> index 8293152a6dc1..eb3d525731da 100644
> --- a/drivers/net/ethernet/mscc/ocelot_net.c
> +++ b/drivers/net/ethernet/mscc/ocelot_net.c
> @@ -514,10 +514,7 @@ static netdev_tx_t ocelot_port_xmit(struct sk_buff *skb, struct net_device *dev)
> return NETDEV_TX_OK;
> }
>
> - if (ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP) {
> - rew_op = ocelot_port->ptp_cmd;
> - rew_op |= clone->cb[0] << 3;
> - }
> + ocelot_ptp_rew_op(skb, clone, &rew_op);
> }
>
> ocelot_port_inject_frame(ocelot, port, 0, rew_op, skb);
> diff --git a/include/soc/mscc/ocelot.h b/include/soc/mscc/ocelot.h
> index 9cdaf1d9199f..19413532db0b 100644
> --- a/include/soc/mscc/ocelot.h
> +++ b/include/soc/mscc/ocelot.h
> @@ -820,6 +820,7 @@ int ocelot_vlan_add(struct ocelot *ocelot, int port, u16 vid, bool pvid,
> int ocelot_vlan_del(struct ocelot *ocelot, int port, u16 vid);
> int ocelot_hwstamp_get(struct ocelot *ocelot, int port, struct ifreq *ifr);
> int ocelot_hwstamp_set(struct ocelot *ocelot, int port, struct ifreq *ifr);
> +bool ocelot_ptp_rew_op(struct sk_buff *skb, struct sk_buff *clone, u32 *rew_op);
> int ocelot_port_txtstamp_request(struct ocelot *ocelot, int port,
> struct sk_buff *skb,
> struct sk_buff **clone);
> diff --git a/net/dsa/tag_ocelot.c b/net/dsa/tag_ocelot.c
> index f9df9cac81c5..d5c73b36f0c1 100644
> --- a/net/dsa/tag_ocelot.c
> +++ b/net/dsa/tag_ocelot.c
> @@ -5,25 +5,6 @@
> #include <soc/mscc/ocelot.h>
> #include "dsa_priv.h"
>
> -static void ocelot_xmit_ptp(struct dsa_port *dp, void *injection,
> - struct sk_buff *clone)
> -{
> - struct ocelot *ocelot = dp->ds->priv;
> - struct ocelot_port *ocelot_port;
> - u64 rew_op;
> -
> - ocelot_port = ocelot->ports[dp->index];
> - rew_op = ocelot_port->ptp_cmd;
> -
> - /* Retrieve timestamp ID populated inside skb->cb[0] of the
> - * clone by ocelot_port_add_txtstamp_skb
> - */
> - if (ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP)
> - rew_op |= clone->cb[0] << 3;
> -
> - ocelot_ifh_set_rew_op(injection, rew_op);
> -}
> -
> static void ocelot_xmit_common(struct sk_buff *skb, struct net_device *netdev,
> __be32 ifh_prefix, void **ifh)
> {
> @@ -32,6 +13,7 @@ static void ocelot_xmit_common(struct sk_buff *skb, struct net_device *netdev,
> struct dsa_switch *ds = dp->ds;
> void *injection;
> __be32 *prefix;
> + u32 rew_op = 0;
>
> injection = skb_push(skb, OCELOT_TAG_LEN);
> prefix = skb_push(skb, OCELOT_SHORT_PREFIX_LEN);
> @@ -42,9 +24,8 @@ static void ocelot_xmit_common(struct sk_buff *skb, struct net_device *netdev,
> ocelot_ifh_set_src(injection, ds->num_ports);
> ocelot_ifh_set_qos_class(injection, skb->priority);
>
> - /* TX timestamping was requested */
> - if (clone)
> - ocelot_xmit_ptp(dp, injection, clone);
> + if (ocelot_ptp_rew_op(skb, clone, &rew_op))
> + ocelot_ifh_set_rew_op(injection, rew_op);
>
> *ifh = injection;
> }
> diff --git a/net/dsa/tag_ocelot_8021q.c b/net/dsa/tag_ocelot_8021q.c
> index 5f3e8e124a82..bf32649a5a7b 100644
> --- a/net/dsa/tag_ocelot_8021q.c
> +++ b/net/dsa/tag_ocelot_8021q.c
> @@ -13,32 +13,6 @@
> #include <soc/mscc/ocelot_ptp.h>
> #include "dsa_priv.h"
>
> -static struct sk_buff *ocelot_xmit_ptp(struct dsa_port *dp,
> - struct sk_buff *skb,
> - struct sk_buff *clone)
> -{
> - struct ocelot *ocelot = dp->ds->priv;
> - struct ocelot_port *ocelot_port;
> - int port = dp->index;
> - u32 rew_op;
> -
> - if (!ocelot_can_inject(ocelot, 0))
> - return NULL;
> -
> - ocelot_port = ocelot->ports[port];
> - rew_op = ocelot_port->ptp_cmd;
> -
> - /* Retrieve timestamp ID populated inside skb->cb[0] of the
> - * clone by ocelot_port_add_txtstamp_skb
> - */
> - if (ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP)
> - rew_op |= clone->cb[0] << 3;
> -
> - ocelot_port_inject_frame(ocelot, port, 0, rew_op, skb);
> -
> - return NULL;
> -}
> -
> static struct sk_buff *ocelot_xmit(struct sk_buff *skb,
> struct net_device *netdev)
> {
> @@ -47,10 +21,17 @@ static struct sk_buff *ocelot_xmit(struct sk_buff *skb,
> u16 queue_mapping = skb_get_queue_mapping(skb);
> u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
> struct sk_buff *clone = DSA_SKB_CB(skb)->clone;
> + struct ocelot *ocelot = dp->ds->priv;
> + int port = dp->index;
> + u32 rew_op = 0;
> +
> + if (ocelot_ptp_rew_op(skb, clone, &rew_op)) {
> + if (!ocelot_can_inject(ocelot, 0))
> + return NULL;
>
> - /* TX timestamping was requested, so inject through MMIO */
> - if (clone)
> - return ocelot_xmit_ptp(dp, skb, clone);
> + ocelot_port_inject_frame(ocelot, port, 0, rew_op, skb);
> + return NULL;
> + }
>
> return dsa_8021q_xmit(skb, netdev, ETH_P_8021Q,
> ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
> --
> 2.25.1
>
