From: Arınç ÜNAL arinc.unal@arinc9.com
[ Upstream commit 69ddba9d170bdaee1dc0eb4ced38d7e4bb7b92af ]
Currently, the MT753X switches treat frames with :01-0D and :0F MAC DAs as regular multicast frames, therefore flooding them to user ports.
On page 205, section "8.6.3 Frame filtering" of the active standard, IEEE Std 802.1Q™-2022, it is stated that frames with 01:80:C2:00:00:00-0F as MAC DA must only be propagated to C-VLAN and MAC Bridge components. That means VLAN-aware and VLAN-unaware bridges. On the switch designs with CPU ports, these frames are supposed to be processed by the CPU (software). So we make the switch only forward them to the CPU port. And if received from a CPU port, forward to a single port. The software is responsible of making the switch conform to the latter by setting a single port as destination port on the special tag.
This switch intellectual property cannot conform to this part of the standard fully. Whilst the REV_UN frame tag covers the remaining :04-0D and :0F MAC DAs, it also includes :22-FF which the scope of propagation is not supposed to be restricted for these MAC DAs.
Set frames with :01-03 MAC DAs to be trapped to the CPU port(s). Add a comment for the remaining MAC DAs.
Note that the ingress port must have a PVID assigned to it for the switch to forward untagged frames. A PVID is set by default on VLAN-aware and VLAN-unaware ports. However, when the network interface that pertains to the ingress port is attached to a vlan_filtering enabled bridge, the user can remove the PVID assignment from it which would prevent the link-local frames from being trapped to the CPU port. I am yet to see a way to forward link-local frames while preventing other untagged frames from being forwarded too.
Fixes: b8f126a8d543 ("net-next: dsa: add dsa support for Mediatek MT7530 switch") Signed-off-by: Arınç ÜNAL arinc.unal@arinc9.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/dsa/mt7530.c | 37 +++++++++++++++++++++++++++++++++---- drivers/net/dsa/mt7530.h | 13 +++++++++++++ 2 files changed, 46 insertions(+), 4 deletions(-)
diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c index ae39d669d30ce..40ae44c9945b1 100644 --- a/drivers/net/dsa/mt7530.c +++ b/drivers/net/dsa/mt7530.c @@ -998,6 +998,21 @@ static void mt7530_setup_port5(struct dsa_switch *ds, phy_interface_t interface) mutex_unlock(&priv->reg_mutex); }
+/* On page 205, section "8.6.3 Frame filtering" of the active standard, IEEE Std + * 802.1Q™-2022, it is stated that frames with 01:80:C2:00:00:00-0F as MAC DA + * must only be propagated to C-VLAN and MAC Bridge components. That means + * VLAN-aware and VLAN-unaware bridges. On the switch designs with CPU ports, + * these frames are supposed to be processed by the CPU (software). So we make + * the switch only forward them to the CPU port. And if received from a CPU + * port, forward to a single port. The software is responsible of making the + * switch conform to the latter by setting a single port as destination port on + * the special tag. + * + * This switch intellectual property cannot conform to this part of the standard + * fully. Whilst the REV_UN frame tag covers the remaining :04-0D and :0F MAC + * DAs, it also includes :22-FF which the scope of propagation is not supposed + * to be restricted for these MAC DAs. + */ static void mt753x_trap_frames(struct mt7530_priv *priv) { @@ -1012,13 +1027,27 @@ mt753x_trap_frames(struct mt7530_priv *priv) MT753X_BPDU_EG_TAG(MT7530_VLAN_EG_UNTAGGED) | MT753X_BPDU_CPU_ONLY);
- /* Trap LLDP frames with :0E MAC DA to the CPU port(s) and egress them - * VLAN-untagged. + /* Trap frames with :01 and :02 MAC DAs to the CPU port(s) and egress + * them VLAN-untagged. + */ + mt7530_rmw(priv, MT753X_RGAC1, MT753X_R02_EG_TAG_MASK | + MT753X_R02_PORT_FW_MASK | MT753X_R01_EG_TAG_MASK | + MT753X_R01_PORT_FW_MASK, + MT753X_R02_EG_TAG(MT7530_VLAN_EG_UNTAGGED) | + MT753X_R02_PORT_FW(MT753X_BPDU_CPU_ONLY) | + MT753X_R01_EG_TAG(MT7530_VLAN_EG_UNTAGGED) | + MT753X_BPDU_CPU_ONLY); + + /* Trap frames with :03 and :0E MAC DAs to the CPU port(s) and egress + * them VLAN-untagged. */ mt7530_rmw(priv, MT753X_RGAC2, MT753X_R0E_EG_TAG_MASK | - MT753X_R0E_PORT_FW_MASK, + MT753X_R0E_PORT_FW_MASK | MT753X_R03_EG_TAG_MASK | + MT753X_R03_PORT_FW_MASK, MT753X_R0E_EG_TAG(MT7530_VLAN_EG_UNTAGGED) | - MT753X_R0E_PORT_FW(MT753X_BPDU_CPU_ONLY)); + MT753X_R0E_PORT_FW(MT753X_BPDU_CPU_ONLY) | + MT753X_R03_EG_TAG(MT7530_VLAN_EG_UNTAGGED) | + MT753X_BPDU_CPU_ONLY); }
static int diff --git a/drivers/net/dsa/mt7530.h b/drivers/net/dsa/mt7530.h index cef2af3f24d58..75bc9043c8c0a 100644 --- a/drivers/net/dsa/mt7530.h +++ b/drivers/net/dsa/mt7530.h @@ -73,12 +73,25 @@ enum mt753x_id { #define MT753X_BPDU_EG_TAG(x) FIELD_PREP(MT753X_BPDU_EG_TAG_MASK, x) #define MT753X_BPDU_PORT_FW_MASK GENMASK(2, 0)
+/* Register for :01 and :02 MAC DA frame control */ +#define MT753X_RGAC1 0x28 +#define MT753X_R02_EG_TAG_MASK GENMASK(24, 22) +#define MT753X_R02_EG_TAG(x) FIELD_PREP(MT753X_R02_EG_TAG_MASK, x) +#define MT753X_R02_PORT_FW_MASK GENMASK(18, 16) +#define MT753X_R02_PORT_FW(x) FIELD_PREP(MT753X_R02_PORT_FW_MASK, x) +#define MT753X_R01_EG_TAG_MASK GENMASK(8, 6) +#define MT753X_R01_EG_TAG(x) FIELD_PREP(MT753X_R01_EG_TAG_MASK, x) +#define MT753X_R01_PORT_FW_MASK GENMASK(2, 0) + /* Register for :03 and :0E MAC DA frame control */ #define MT753X_RGAC2 0x2c #define MT753X_R0E_EG_TAG_MASK GENMASK(24, 22) #define MT753X_R0E_EG_TAG(x) FIELD_PREP(MT753X_R0E_EG_TAG_MASK, x) #define MT753X_R0E_PORT_FW_MASK GENMASK(18, 16) #define MT753X_R0E_PORT_FW(x) FIELD_PREP(MT753X_R0E_PORT_FW_MASK, x) +#define MT753X_R03_EG_TAG_MASK GENMASK(8, 6) +#define MT753X_R03_EG_TAG(x) FIELD_PREP(MT753X_R03_EG_TAG_MASK, x) +#define MT753X_R03_PORT_FW_MASK GENMASK(2, 0)
enum mt753x_bpdu_port_fw { MT753X_BPDU_FOLLOW_MFC,