[RFC PATCH net-next] net: dsa: tag_sja1105: be dsa_loop-safe
From: Vladimir Oltean <vladimir.oltean@nxp.com>
Date: 2021-08-16 09:55:49
Subsystem:
networking drivers, networking [dsa], networking [general], the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Andrew Lunn, Vladimir Oltean, Linus Torvalds
Add support for tag_sja1105 running on non-sja1105 DSA ports, by making sure that every time we dereference dp->priv, we check the switch's dsa_switch_ops (otherwise we access a struct sja1105_port structure that is in fact something else). This adds an unconditional build-time dependency between sja1105 being built as module => tag_sja1105 must also be built as module. This was there only for PTP before. Some sane defaults must also take place when not running on sja1105 hardware. These are: - sja1105_xmit_tpid: the sja1105 driver uses different VLAN protocols depending on VLAN awareness and switch revision (when an encapsulated VLAN must be sent). Default to 0x8100. - sja1105_rcv_meta_state_machine: this aggregates PTP frames with their metadata timestamp frames. When running on non-sja1105 hardware, don't do that and accept all frames unmodified. - sja1105_defer_xmit: calls sja1105_port_deferred_xmit in sja1105_main.c which writes a management route over SPI. When not running on sja1105 hardware, bypass the SPI write and send the frame as-is. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> --- drivers/net/dsa/sja1105/sja1105_main.c | 5 ++-- include/linux/dsa/sja1105.h | 18 ++++++++++++ net/dsa/Kconfig | 2 +- net/dsa/tag_sja1105.c | 39 ++++++++++++++++++-------- 4 files changed, 48 insertions(+), 16 deletions(-)
diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c
index 7074b00fb9e7..1a041fa7fa86 100644
--- a/drivers/net/dsa/sja1105/sja1105_main.c
+++ b/drivers/net/dsa/sja1105/sja1105_main.c@@ -28,8 +28,6 @@ #define SJA1105_UNKNOWN_MULTICAST 0x010000000000ull #define SJA1105_DEFAULT_VLAN (VLAN_N_VID - 1) -static const struct dsa_switch_ops sja1105_switch_ops; - static void sja1105_hw_reset(struct gpio_desc *gpio, unsigned int pulse_len, unsigned int startup_delay) {
@@ -3120,7 +3118,7 @@ static void sja1105_teardown(struct dsa_switch *ds) sja1105_static_config_free(&priv->static_config); } -static const struct dsa_switch_ops sja1105_switch_ops = { +const struct dsa_switch_ops sja1105_switch_ops = { .get_tag_protocol = sja1105_get_tag_protocol, .setup = sja1105_setup, .teardown = sja1105_teardown,
@@ -3169,6 +3167,7 @@ static const struct dsa_switch_ops sja1105_switch_ops = { .port_bridge_tx_fwd_offload = dsa_tag_8021q_bridge_tx_fwd_offload, .port_bridge_tx_fwd_unoffload = dsa_tag_8021q_bridge_tx_fwd_unoffload, }; +EXPORT_SYMBOL_GPL(sja1105_switch_ops); static const struct of_device_id sja1105_dt_ids[];
diff --git a/include/linux/dsa/sja1105.h b/include/linux/dsa/sja1105.h
index 0eadc7ac44ec..6b0dc9ff92d1 100644
--- a/include/linux/dsa/sja1105.h
+++ b/include/linux/dsa/sja1105.h@@ -88,4 +88,22 @@ static inline void sja1110_process_meta_tstamp(struct dsa_switch *ds, int port, #endif /* IS_ENABLED(CONFIG_NET_DSA_SJA1105_PTP) */ +#if IS_ENABLED(CONFIG_NET_DSA_SJA1105) + +extern const struct dsa_switch_ops sja1105_switch_ops; + +static inline bool dsa_port_is_sja1105(struct dsa_port *dp) +{ + return dp->ds->ops == &sja1105_switch_ops; +} + +#else + +static inline bool dsa_port_is_sja1105(struct dsa_port *dp) +{ + return false; +} + +#endif + #endif /* _NET_DSA_SJA1105_H */
diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig
index 970906eb5b2c..548285539752 100644
--- a/net/dsa/Kconfig
+++ b/net/dsa/Kconfig@@ -138,7 +138,7 @@ config NET_DSA_TAG_LAN9303 config NET_DSA_TAG_SJA1105 tristate "Tag driver for NXP SJA1105 switches" - depends on (NET_DSA_SJA1105 && NET_DSA_SJA1105_PTP) || !NET_DSA_SJA1105 || !NET_DSA_SJA1105_PTP + depends on NET_DSA_SJA1105 || !NET_DSA_SJA1105 select PACKING help Say Y or M if you want to enable support for tagging frames with the
diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c
index 1406bc41d345..5b80a9049e2c 100644
--- a/net/dsa/tag_sja1105.c
+++ b/net/dsa/tag_sja1105.c@@ -116,9 +116,14 @@ static inline bool sja1105_is_meta_frame(const struct sk_buff *skb) } /* Calls sja1105_port_deferred_xmit in sja1105_main.c */ -static struct sk_buff *sja1105_defer_xmit(struct sja1105_port *sp, +static struct sk_buff *sja1105_defer_xmit(struct dsa_port *dp, struct sk_buff *skb) { + struct sja1105_port *sp = dp->priv; + + if (!dsa_port_is_sja1105(dp)) + return skb; + /* Increase refcount so the kfree_skb in dsa_slave_xmit * won't really free the packet. */
@@ -128,8 +133,13 @@ static struct sk_buff *sja1105_defer_xmit(struct sja1105_port *sp, return NULL; } -static u16 sja1105_xmit_tpid(struct sja1105_port *sp) +static u16 sja1105_xmit_tpid(struct dsa_port *dp) { + struct sja1105_port *sp = dp->priv; + + if (unlikely(!dsa_port_is_sja1105(dp))) + return ETH_P_8021Q; + return sp->xmit_tpid; }
@@ -155,7 +165,7 @@ static struct sk_buff *sja1105_imprecise_xmit(struct sk_buff *skb, */ tx_vid = dsa_8021q_bridge_tx_fwd_offload_vid(dp->bridge_num); - return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp->priv), tx_vid); + return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp), tx_vid); } static struct sk_buff *sja1105_xmit(struct sk_buff *skb,
@@ -174,9 +184,9 @@ static struct sk_buff *sja1105_xmit(struct sk_buff *skb, * is the .port_deferred_xmit driver callback. */ if (unlikely(sja1105_is_link_local(skb))) - return sja1105_defer_xmit(dp->priv, skb); + return sja1105_defer_xmit(dp, skb); - return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp->priv), + return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp), ((pcp << VLAN_PRIO_SHIFT) | tx_vid)); }
@@ -200,7 +210,7 @@ static struct sk_buff *sja1110_xmit(struct sk_buff *skb, * tag_8021q TX VLANs. */ if (likely(!sja1105_is_link_local(skb))) - return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp->priv), + return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp), ((pcp << VLAN_PRIO_SHIFT) | tx_vid)); skb_push(skb, SJA1110_HEADER_LEN);
@@ -265,16 +275,16 @@ static struct sk_buff bool is_link_local, bool is_meta) { - struct sja1105_port *sp; - struct dsa_port *dp; - - dp = dsa_slave_to_port(skb->dev); - sp = dp->priv; - /* Step 1: A timestampable frame was received. * Buffer it until we get its meta frame. */ if (is_link_local) { + struct dsa_port *dp = dsa_slave_to_port(skb->dev); + struct sja1105_port *sp = dp->priv; + + if (unlikely(!dsa_port_is_sja1105(dp))) + return skb; + if (!test_bit(SJA1105_HWTS_RX_EN, &sp->data->state)) /* Do normal processing. */ return skb;
@@ -307,8 +317,13 @@ static struct sk_buff * frame, which serves no further purpose). */ } else if (is_meta) { + struct dsa_port *dp = dsa_slave_to_port(skb->dev); + struct sja1105_port *sp = dp->priv; struct sk_buff *stampable_skb; + if (unlikely(!dsa_port_is_sja1105(dp))) + return skb; + /* Drop the meta frame if we're not in the right state * to process it. */
--
2.25.1