From 0ed19e4b67359e689e01f45351844a8a7d9051f7 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Sun, 14 Feb 2021 00:37:58 +0200 Subject: [PATCH] net: dsa: tag_ocelot: create separate tagger for Seville The ocelot tagger is a hot mess currently, it relies on memory initialized by the attached driver for basic frame transmission. This is against all that DSA tagging protocols stand for, which is that the transmission and reception of a DSA-tagged frame, the data path, should be independent from the switch control path, because the tag protocol is in principle hot-pluggable and reusable across switches (even if in practice it wasn't until very recently). But if another driver like dsa_loop wants to make use of tag_ocelot, it couldn't. This was done to have common code between Felix and Ocelot, which have one bit difference in the frame header format. Quoting from commit ab007097c35a ("net: dsa: felix: create a template for the DSA tags on xmit"): Other alternatives have been analyzed, such as: - Create a separate tag_seville.c: too much code duplication for just 1 bit field difference. - Create a separate DSA_TAG_PROTO_SEVILLE under tag_ocelot.c, just like tag_brcm.c, which would have a separate .xmit function. Again, too much code duplication for just 1 bit field difference. - Allocate the template from the init function of the tag_ocelot.c module, instead of from the driver: couldn't figure out a method of accessing the correct port template corresponding to the correct tagger in the .xmit function. The really interesting part is that Seville should have had its own tagging protocol defined - it is not compatible on the wire with Ocelot, even for that single bit. In principle, a packet generated by DSA_TAG_PROTO_OCELOT when booted on NXP LS1028A would look in a certain way, but when booted on NXP T1040 it would look differently. The reverse is also true: a packet generated by a Seville switch would be interpreted incorrectly by Wireshark if it was told it was generated by an Ocelot switch. Actually things are a bit more nuanced. If we concentrate only on the DSA tag, what I said above is true, but Ocelot/Seville also support an optional DSA tag prefix, which can be short or long, and it is possible to distinguish the two taggers based on an integer constant put in that prefix. Nonetheless, creating a separate tagger is still justified, since the tag prefix is optional, and without it, there is again no way to distinguish. Claiming backwards binary compatibility is a bit more tough, since I've already changed the format of tag_ocelot once, in commit 0f1fa5bbd4c3 ("net: dsa: tag_ocelot: use a short prefix on both ingress and egress"). Therefore I am not very concerned with treating this as a bugfix and backporting it to stable kernels (which would be another mess due to the fact that there would be lots of conflicts with the other DSA_TAG_PROTO* definitions). It's just simpler to say that the string values of the taggers have ABI value starting with kernel 5.12, which will be when the changing of tag protocol via /sys/class/net//dsa/tagging goes live. Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- drivers/net/dsa/ocelot/felix.c | 18 ++----- drivers/net/dsa/ocelot/felix.h | 1 - drivers/net/dsa/ocelot/felix_vsc9959.c | 26 --------- drivers/net/dsa/ocelot/seville_vsc9953.c | 28 +--------- include/linux/dsa/ocelot.h | 10 ++++ include/net/dsa.h | 2 + net/dsa/tag_ocelot.c | 68 ++++++++++++++++++------ 7 files changed, 70 insertions(+), 83 deletions(-) diff --git a/drivers/net/dsa/ocelot/felix.c b/drivers/net/dsa/ocelot/felix.c index 60e0d354adea9..7e1f6350139bd 100644 --- a/drivers/net/dsa/ocelot/felix.c +++ b/drivers/net/dsa/ocelot/felix.c @@ -431,6 +431,7 @@ static int felix_set_tag_protocol(struct dsa_switch *ds, int cpu, int err; switch (proto) { + case DSA_TAG_PROTO_SEVILLE: case DSA_TAG_PROTO_OCELOT: err = felix_setup_tag_npi(ds, cpu); break; @@ -448,6 +449,7 @@ static void felix_del_tag_protocol(struct dsa_switch *ds, int cpu, enum dsa_tag_protocol proto) { switch (proto) { + case DSA_TAG_PROTO_SEVILLE: case DSA_TAG_PROTO_OCELOT: felix_teardown_tag_npi(ds, cpu); break; @@ -471,7 +473,8 @@ static int felix_change_tag_protocol(struct dsa_switch *ds, int cpu, enum dsa_tag_protocol old_proto = felix->tag_proto; int err; - if (proto != DSA_TAG_PROTO_OCELOT && + if (proto != DSA_TAG_PROTO_SEVILLE && + proto != DSA_TAG_PROTO_OCELOT && proto != DSA_TAG_PROTO_OCELOT_8021Q) return -EPROTONOSUPPORT; @@ -1003,7 +1006,6 @@ static int felix_init_structs(struct felix *felix, int num_phys_ports) for (port = 0; port < num_phys_ports; port++) { struct ocelot_port *ocelot_port; struct regmap *target; - u8 *template; ocelot_port = devm_kzalloc(ocelot->dev, sizeof(struct ocelot_port), @@ -1029,22 +1031,10 @@ static int felix_init_structs(struct felix *felix, int num_phys_ports) return PTR_ERR(target); } - template = devm_kzalloc(ocelot->dev, OCELOT_TOTAL_TAG_LEN, - GFP_KERNEL); - if (!template) { - dev_err(ocelot->dev, - "Failed to allocate memory for DSA tag\n"); - kfree(port_phy_modes); - return -ENOMEM; - } - ocelot_port->phy_mode = port_phy_modes[port]; ocelot_port->ocelot = ocelot; ocelot_port->target = target; - ocelot_port->xmit_template = template; ocelot->ports[port] = ocelot_port; - - felix->info->xmit_template_populate(ocelot, port); } kfree(port_phy_modes); diff --git a/drivers/net/dsa/ocelot/felix.h b/drivers/net/dsa/ocelot/felix.h index 9d4459f2fffb8..b2ea425c5803b 100644 --- a/drivers/net/dsa/ocelot/felix.h +++ b/drivers/net/dsa/ocelot/felix.h @@ -34,7 +34,6 @@ struct felix_info { enum tc_setup_type type, void *type_data); void (*port_sched_speed_set)(struct ocelot *ocelot, int port, u32 speed); - void (*xmit_template_populate)(struct ocelot *ocelot, int port); }; extern const struct dsa_switch_ops felix_switch_ops; diff --git a/drivers/net/dsa/ocelot/felix_vsc9959.c b/drivers/net/dsa/ocelot/felix_vsc9959.c index cacc6f9c01135..32b885fcaf900 100644 --- a/drivers/net/dsa/ocelot/felix_vsc9959.c +++ b/drivers/net/dsa/ocelot/felix_vsc9959.c @@ -1339,31 +1339,6 @@ static int vsc9959_port_setup_tc(struct dsa_switch *ds, int port, } } -static void vsc9959_xmit_template_populate(struct ocelot *ocelot, int port) -{ - struct ocelot_port *ocelot_port = ocelot->ports[port]; - u8 *template = ocelot_port->xmit_template; - u64 bypass, dest, src; - __be32 *prefix; - u8 *injection; - - /* Set the source port as the CPU port module and not the - * NPI port - */ - src = ocelot->num_phys_ports; - dest = BIT(port); - bypass = true; - - injection = template + OCELOT_SHORT_PREFIX_LEN; - prefix = (__be32 *)template; - - packing(injection, &bypass, 127, 127, OCELOT_TAG_LEN, PACK, 0); - packing(injection, &dest, 68, 56, OCELOT_TAG_LEN, PACK, 0); - packing(injection, &src, 46, 43, OCELOT_TAG_LEN, PACK, 0); - - *prefix = cpu_to_be32(0x8880000a); -} - static const struct felix_info felix_info_vsc9959 = { .target_io_res = vsc9959_target_io_res, .port_io_res = vsc9959_port_io_res, @@ -1386,7 +1361,6 @@ static const struct felix_info felix_info_vsc9959 = { .prevalidate_phy_mode = vsc9959_prevalidate_phy_mode, .port_setup_tc = vsc9959_port_setup_tc, .port_sched_speed_set = vsc9959_sched_speed_set, - .xmit_template_populate = vsc9959_xmit_template_populate, }; static irqreturn_t felix_irq_handler(int irq, void *data) diff --git a/drivers/net/dsa/ocelot/seville_vsc9953.c b/drivers/net/dsa/ocelot/seville_vsc9953.c index d7348ea4831e7..84f93a874d502 100644 --- a/drivers/net/dsa/ocelot/seville_vsc9953.c +++ b/drivers/net/dsa/ocelot/seville_vsc9953.c @@ -1165,31 +1165,6 @@ static void vsc9953_mdio_bus_free(struct ocelot *ocelot) mdiobus_unregister(felix->imdio); } -static void vsc9953_xmit_template_populate(struct ocelot *ocelot, int port) -{ - struct ocelot_port *ocelot_port = ocelot->ports[port]; - u8 *template = ocelot_port->xmit_template; - u64 bypass, dest, src; - __be32 *prefix; - u8 *injection; - - /* Set the source port as the CPU port module and not the - * NPI port - */ - src = ocelot->num_phys_ports; - dest = BIT(port); - bypass = true; - - injection = template + OCELOT_SHORT_PREFIX_LEN; - prefix = (__be32 *)template; - - packing(injection, &bypass, 127, 127, OCELOT_TAG_LEN, PACK, 0); - packing(injection, &dest, 67, 57, OCELOT_TAG_LEN, PACK, 0); - packing(injection, &src, 46, 43, OCELOT_TAG_LEN, PACK, 0); - - *prefix = cpu_to_be32(0x88800005); -} - static const struct felix_info seville_info_vsc9953 = { .target_io_res = vsc9953_target_io_res, .port_io_res = vsc9953_port_io_res, @@ -1206,7 +1181,6 @@ static const struct felix_info seville_info_vsc9953 = { .mdio_bus_free = vsc9953_mdio_bus_free, .phylink_validate = vsc9953_phylink_validate, .prevalidate_phy_mode = vsc9953_prevalidate_phy_mode, - .xmit_template_populate = vsc9953_xmit_template_populate, }; static int seville_probe(struct platform_device *pdev) @@ -1246,7 +1220,7 @@ static int seville_probe(struct platform_device *pdev) ds->ops = &felix_switch_ops; ds->priv = ocelot; felix->ds = ds; - felix->tag_proto = DSA_TAG_PROTO_OCELOT; + felix->tag_proto = DSA_TAG_PROTO_SEVILLE; err = dsa_register_switch(ds); if (err) { diff --git a/include/linux/dsa/ocelot.h b/include/linux/dsa/ocelot.h index 763dbbfaff7a9..c6bc45ae5e03a 100644 --- a/include/linux/dsa/ocelot.h +++ b/include/linux/dsa/ocelot.h @@ -195,6 +195,16 @@ static inline void ocelot_ifh_set_qos_class(void *injection, u64 qos_class) packing(injection, &qos_class, 19, 17, OCELOT_TAG_LEN, PACK, 0); } +static inline void seville_ifh_set_dest(void *injection, u64 dest) +{ + packing(injection, &dest, 67, 57, OCELOT_TAG_LEN, PACK, 0); +} + +static inline void ocelot_ifh_set_src(void *injection, u64 src) +{ + packing(injection, &src, 46, 43, OCELOT_TAG_LEN, PACK, 0); +} + static inline void ocelot_ifh_set_tag_type(void *injection, u64 tag_type) { packing(injection, &tag_type, 16, 16, OCELOT_TAG_LEN, PACK, 0); diff --git a/include/net/dsa.h b/include/net/dsa.h index 74457aaffec77..b095ef114fe87 100644 --- a/include/net/dsa.h +++ b/include/net/dsa.h @@ -48,6 +48,7 @@ struct phylink_link_state; #define DSA_TAG_PROTO_HELLCREEK_VALUE 18 #define DSA_TAG_PROTO_XRS700X_VALUE 19 #define DSA_TAG_PROTO_OCELOT_8021Q_VALUE 20 +#define DSA_TAG_PROTO_SEVILLE_VALUE 21 enum dsa_tag_protocol { DSA_TAG_PROTO_NONE = DSA_TAG_PROTO_NONE_VALUE, @@ -71,6 +72,7 @@ enum dsa_tag_protocol { DSA_TAG_PROTO_HELLCREEK = DSA_TAG_PROTO_HELLCREEK_VALUE, DSA_TAG_PROTO_XRS700X = DSA_TAG_PROTO_XRS700X_VALUE, DSA_TAG_PROTO_OCELOT_8021Q = DSA_TAG_PROTO_OCELOT_8021Q_VALUE, + DSA_TAG_PROTO_SEVILLE = DSA_TAG_PROTO_SEVILLE_VALUE, }; struct packet_type; diff --git a/net/dsa/tag_ocelot.c b/net/dsa/tag_ocelot.c index fe00519229d7b..a7dd61c8e0051 100644 --- a/net/dsa/tag_ocelot.c +++ b/net/dsa/tag_ocelot.c @@ -24,33 +24,52 @@ static void ocelot_xmit_ptp(struct dsa_port *dp, void *injection, ocelot_ifh_set_rew_op(injection, rew_op); } -static struct sk_buff *ocelot_xmit(struct sk_buff *skb, - struct net_device *netdev) +static void ocelot_xmit_common(struct sk_buff *skb, struct net_device *netdev, + __be32 ifh_prefix, void **ifh) { struct dsa_port *dp = dsa_slave_to_port(netdev); struct sk_buff *clone = DSA_SKB_CB(skb)->clone; struct dsa_switch *ds = dp->ds; - struct ocelot *ocelot = ds->priv; - struct ocelot_port *ocelot_port; - u8 *prefix, *injection; - - ocelot_port = ocelot->ports[dp->index]; + void *injection; + __be32 *prefix; injection = skb_push(skb, OCELOT_TAG_LEN); - prefix = skb_push(skb, OCELOT_SHORT_PREFIX_LEN); - memcpy(prefix, ocelot_port->xmit_template, OCELOT_TOTAL_TAG_LEN); - - /* Fix up the fields which are not statically determined - * in the template - */ + *prefix = ifh_prefix; + memset(injection, 0, OCELOT_TAG_LEN); + ocelot_ifh_set_bypass(injection, 1); + 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); + *ifh = injection; +} + +static struct sk_buff *ocelot_xmit(struct sk_buff *skb, + struct net_device *netdev) +{ + struct dsa_port *dp = dsa_slave_to_port(netdev); + void *injection; + + ocelot_xmit_common(skb, netdev, cpu_to_be32(0x8880000a), &injection); + ocelot_ifh_set_dest(injection, BIT(dp->index)); + + return skb; +} + +static struct sk_buff *seville_xmit(struct sk_buff *skb, + struct net_device *netdev) +{ + struct dsa_port *dp = dsa_slave_to_port(netdev); + void *injection; + + ocelot_xmit_common(skb, netdev, cpu_to_be32(0x88800005), &injection); + seville_ifh_set_dest(injection, BIT(dp->index)); + return skb; } @@ -147,7 +166,26 @@ static const struct dsa_device_ops ocelot_netdev_ops = { .promisc_on_master = true, }; -MODULE_LICENSE("GPL v2"); +DSA_TAG_DRIVER(ocelot_netdev_ops); MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT); -module_dsa_tag_driver(ocelot_netdev_ops); +static const struct dsa_device_ops seville_netdev_ops = { + .name = "seville", + .proto = DSA_TAG_PROTO_SEVILLE, + .xmit = seville_xmit, + .rcv = ocelot_rcv, + .overhead = OCELOT_TOTAL_TAG_LEN, + .promisc_on_master = true, +}; + +DSA_TAG_DRIVER(seville_netdev_ops); +MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SEVILLE); + +static struct dsa_tag_driver *ocelot_tag_driver_array[] = { + &DSA_TAG_DRIVER_NAME(ocelot_netdev_ops), + &DSA_TAG_DRIVER_NAME(seville_netdev_ops), +}; + +module_dsa_tag_drivers(ocelot_tag_driver_array); + +MODULE_LICENSE("GPL v2"); -- 2.39.5