[PATCH v2 net-next 08/15] net: dsa: sja1105: prepare tagger for handling DSA tags and VLAN simultaneously
From: Vladimir Oltean
Date: Mon May 11 2020 - 09:54:49 EST
From: Vladimir Oltean <vladimir.oltean@xxxxxxx>
In VLAN-unaware mode, sja1105 uses VLAN tags with a custom TPID of
0xdadb. While in the yet-to-be introduced best_effort_vlan_filtering
mode, it needs to work with normal VLAN TPID values.
A complication arises when we must transmit a VLAN-tagged packet to the
switch when it's in VLAN-aware mode. We need to construct a packet with
2 VLAN tags, and the switch will use the outer header for routing and
pop it on egress. But sadly, here the 2 hardware generations don't
behave the same:
- E/T switches won't pop an ETH_P_8021AD tag on egress, it seems
(packets will remain double-tagged).
- P/Q/R/S switches will drop a packet with 2 ETH_P_8021Q tags (it looks
like it tries to prevent VLAN hopping).
But looks like the reverse is also true:
- E/T switches have no problem popping the outer tag from packets with
2 ETH_P_8021Q tags.
- P/Q/R/S will have no problem popping a single tag even if that is
ETH_P_8021AD.
So it is clear that if we want the hardware to work with dsa_8021q
tagging in VLAN-aware mode, we need to send different TPIDs depending on
revision. Keep that information in priv->info->qinq_tpid.
The per-port tagger structure will hold an xmit_tpid value that depends
not only upon the qinq_tpid, but also upon the VLAN awareness state
itself (in case we must transmit using 0xdadb).
Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
---
Changes in v2:
None.
drivers/net/dsa/sja1105/sja1105.h | 6 ++++++
drivers/net/dsa/sja1105/sja1105_main.c | 10 ++++++++++
drivers/net/dsa/sja1105/sja1105_spi.c | 6 ++++++
include/linux/dsa/sja1105.h | 2 ++
net/dsa/tag_sja1105.c | 17 +++++++----------
5 files changed, 31 insertions(+), 10 deletions(-)
diff --git a/drivers/net/dsa/sja1105/sja1105.h b/drivers/net/dsa/sja1105/sja1105.h
index c80f1999c694..a019ffae38f1 100644
--- a/drivers/net/dsa/sja1105/sja1105.h
+++ b/drivers/net/dsa/sja1105/sja1105.h
@@ -87,6 +87,12 @@ struct sja1105_info {
const struct sja1105_dynamic_table_ops *dyn_ops;
const struct sja1105_table_ops *static_ops;
const struct sja1105_regs *regs;
+ /* Both E/T and P/Q/R/S have quirks when it comes to popping the S-Tag
+ * from double-tagged frames. E/T will pop it only when it's equal to
+ * TPID from the General Parameters Table, while P/Q/R/S will only
+ * pop it when it's equal to TPID2.
+ */
+ u16 qinq_tpid;
int (*reset_cmd)(struct dsa_switch *ds);
int (*setup_rgmii_delay)(const void *ctx, int port);
/* Prototypes from include/net/dsa.h */
diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c
index 82b424a03658..042ecbbc5572 100644
--- a/drivers/net/dsa/sja1105/sja1105_main.c
+++ b/drivers/net/dsa/sja1105/sja1105_main.c
@@ -2153,6 +2153,15 @@ static int sja1105_vlan_filtering(struct dsa_switch *ds, int port, bool enabled)
tpid2 = ETH_P_SJA1105;
}
+ for (port = 0; port < ds->num_ports; port++) {
+ struct sja1105_port *sp = &priv->ports[port];
+
+ if (enabled)
+ sp->xmit_tpid = priv->info->qinq_tpid;
+ else
+ sp->xmit_tpid = ETH_P_SJA1105;
+ }
+
if (!enabled)
state = SJA1105_VLAN_UNAWARE;
else
@@ -2874,6 +2883,7 @@ static int sja1105_probe(struct spi_device *spi)
goto out;
}
skb_queue_head_init(&sp->xmit_queue);
+ sp->xmit_tpid = ETH_P_SJA1105;
}
return 0;
diff --git a/drivers/net/dsa/sja1105/sja1105_spi.c b/drivers/net/dsa/sja1105/sja1105_spi.c
index 0be75c49e6c3..a0dacae803cc 100644
--- a/drivers/net/dsa/sja1105/sja1105_spi.c
+++ b/drivers/net/dsa/sja1105/sja1105_spi.c
@@ -512,6 +512,7 @@ struct sja1105_info sja1105e_info = {
.part_no = SJA1105ET_PART_NO,
.static_ops = sja1105e_table_ops,
.dyn_ops = sja1105et_dyn_ops,
+ .qinq_tpid = ETH_P_8021Q,
.ptp_ts_bits = 24,
.ptpegr_ts_bytes = 4,
.reset_cmd = sja1105et_reset_cmd,
@@ -526,6 +527,7 @@ struct sja1105_info sja1105t_info = {
.part_no = SJA1105ET_PART_NO,
.static_ops = sja1105t_table_ops,
.dyn_ops = sja1105et_dyn_ops,
+ .qinq_tpid = ETH_P_8021Q,
.ptp_ts_bits = 24,
.ptpegr_ts_bytes = 4,
.reset_cmd = sja1105et_reset_cmd,
@@ -540,6 +542,7 @@ struct sja1105_info sja1105p_info = {
.part_no = SJA1105P_PART_NO,
.static_ops = sja1105p_table_ops,
.dyn_ops = sja1105pqrs_dyn_ops,
+ .qinq_tpid = ETH_P_8021AD,
.ptp_ts_bits = 32,
.ptpegr_ts_bytes = 8,
.setup_rgmii_delay = sja1105pqrs_setup_rgmii_delay,
@@ -555,6 +558,7 @@ struct sja1105_info sja1105q_info = {
.part_no = SJA1105Q_PART_NO,
.static_ops = sja1105q_table_ops,
.dyn_ops = sja1105pqrs_dyn_ops,
+ .qinq_tpid = ETH_P_8021AD,
.ptp_ts_bits = 32,
.ptpegr_ts_bytes = 8,
.setup_rgmii_delay = sja1105pqrs_setup_rgmii_delay,
@@ -570,6 +574,7 @@ struct sja1105_info sja1105r_info = {
.part_no = SJA1105R_PART_NO,
.static_ops = sja1105r_table_ops,
.dyn_ops = sja1105pqrs_dyn_ops,
+ .qinq_tpid = ETH_P_8021AD,
.ptp_ts_bits = 32,
.ptpegr_ts_bytes = 8,
.setup_rgmii_delay = sja1105pqrs_setup_rgmii_delay,
@@ -586,6 +591,7 @@ struct sja1105_info sja1105s_info = {
.static_ops = sja1105s_table_ops,
.dyn_ops = sja1105pqrs_dyn_ops,
.regs = &sja1105pqrs_regs,
+ .qinq_tpid = ETH_P_8021AD,
.ptp_ts_bits = 32,
.ptpegr_ts_bytes = 8,
.setup_rgmii_delay = sja1105pqrs_setup_rgmii_delay,
diff --git a/include/linux/dsa/sja1105.h b/include/linux/dsa/sja1105.h
index 136481ce3c6f..e47acf0965c5 100644
--- a/include/linux/dsa/sja1105.h
+++ b/include/linux/dsa/sja1105.h
@@ -9,6 +9,7 @@
#include <linux/skbuff.h>
#include <linux/etherdevice.h>
+#include <linux/dsa/8021q.h>
#include <net/dsa.h>
#define ETH_P_SJA1105 ETH_P_DSA_8021Q
@@ -59,6 +60,7 @@ struct sja1105_port {
struct sja1105_tagger_data *data;
struct dsa_port *dp;
bool hwts_tx_en;
+ u16 xmit_tpid;
};
bool sja1105_can_use_vlan_as_tags(struct dsa_switch *ds);
diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c
index 5368cd34bcf4..0a95fdd7bff8 100644
--- a/net/dsa/tag_sja1105.c
+++ b/net/dsa/tag_sja1105.c
@@ -96,6 +96,11 @@ static struct sk_buff *sja1105_defer_xmit(struct sja1105_port *sp,
return NULL;
}
+static u16 sja1105_xmit_tpid(struct sja1105_port *sp)
+{
+ return sp->xmit_tpid;
+}
+
static struct sk_buff *sja1105_xmit(struct sk_buff *skb,
struct net_device *netdev)
{
@@ -111,15 +116,7 @@ static struct sk_buff *sja1105_xmit(struct sk_buff *skb,
if (unlikely(sja1105_is_link_local(skb)))
return sja1105_defer_xmit(dp->priv, skb);
- /* If we are under a vlan_filtering bridge, IP termination on
- * switch ports based on 802.1Q tags is simply too brittle to
- * be passable. So just defer to the dsa_slave_notag_xmit
- * implementation.
- */
- if (dsa_port_is_vlan_filtering(dp))
- return skb;
-
- return dsa_8021q_xmit(skb, netdev, ETH_P_SJA1105,
+ return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp->priv),
((pcp << VLAN_PRIO_SHIFT) | tx_vid));
}
@@ -258,7 +255,7 @@ static struct sk_buff *sja1105_rcv(struct sk_buff *skb,
hdr = eth_hdr(skb);
tpid = ntohs(hdr->h_proto);
- is_tagged = (tpid == ETH_P_SJA1105);
+ is_tagged = (tpid == ETH_P_SJA1105 || tpid == ETH_P_8021Q);
is_link_local = sja1105_is_link_local(skb);
is_meta = sja1105_is_meta_frame(skb);
--
2.17.1