[PATCH net-next v6 06/16] net: dsa: vsc73xx: add port_stp_state_set function

Pawel Dembicki
2024-03-01T22:17:52Z

This isn't a fully functional implementation of 802.1D, but
port_stp_state_set is required for a future tag8021q operations.

This implementation handles properly all states, but vsc73xx doesn't
forward STP packets.

Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
---
v6:
- fix inconsistent indenting
v5:
- remove unneeded 'RECVMASK' operations
- reorganise vsc73xx_refresh_fwd_map function
v4:
- fully reworked port_stp_state_set
v3:
- use 'VSC73XX_MAX_NUM_PORTS' define
- add 'state == BR_STATE_DISABLED' condition
- fix style issues
v2:
- fix kdoc

drivers/net/dsa/vitesse-vsc73xx-core.c | 99 +++++++++++++++++++++++---
1 file changed, 88 insertions(+), 11 deletions(-)

diff --git a/drivers/net/dsa/vitesse-vsc73xx-core.c b/drivers/net/dsa/vitesse-vsc73xx-core.c
index 425999d7bf41..d1e84a9a83d1 100644
--- a/drivers/net/dsa/vitesse-vsc73xx-core.c
+++ b/drivers/net/dsa/vitesse-vsc73xx-core.c
@@ -164,6 +164,10 @@
#define VSC73XX_AGENCTRL 0xf0
#define VSC73XX_CAPRST 0xff

+#define VSC73XX_SRCMASKS_CPU_COPY BIT(27)
+#define VSC73XX_SRCMASKS_MIRROR BIT(26)
+#define VSC73XX_SRCMASKS_PORTS_MASK GENMASK(7, 0)
+
#define VSC73XX_MACACCESS_CPU_COPY BIT(14)
#define VSC73XX_MACACCESS_FWD_KILL BIT(13)
#define VSC73XX_MACACCESS_IGNORE_VLAN BIT(12)
@@ -623,9 +627,6 @@ static int vsc73xx_setup(struct dsa_switch *ds)
vsc73xx_write(vsc, VSC73XX_BLOCK_SYSTEM, 0, VSC73XX_GMIIDELAY,
VSC73XX_GMIIDELAY_GMII0_GTXDELAY_2_0_NS |
VSC73XX_GMIIDELAY_GMII0_RXDELAY_2_0_NS);
- /* Enable reception of frames on all ports */
- vsc73xx_write(vsc, VSC73XX_BLOCK_ANALYZER, 0, VSC73XX_RECVMASK,
- 0x5f);
/* IP multicast flood mask (table 144) */
vsc73xx_write(vsc, VSC73XX_BLOCK_ANALYZER, 0, VSC73XX_IFLODMSK,
0xff);
@@ -785,10 +786,6 @@ static void vsc73xx_phylink_mac_link_down(struct dsa_switch *ds, int port,
/* Allow backward dropping of frames from this port */
vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ARBITER, 0,
VSC73XX_SBACKWDROP, BIT(port), BIT(port));
-
- /* Receive mask (disable forwarding) */
- vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ANALYZER, 0,
- VSC73XX_RECVMASK, BIT(port), 0);
}

static void vsc73xx_phylink_mac_link_up(struct dsa_switch *ds, int port,
@@ -841,10 +838,6 @@ static void vsc73xx_phylink_mac_link_up(struct dsa_switch *ds, int port,
vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ARBITER, 0,
VSC73XX_ARBDISC, BIT(port), 0);

- /* Enable port (forwarding) in the receieve mask */
- vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ANALYZER, 0,
- VSC73XX_RECVMASK, BIT(port), BIT(port));
-
/* Disallow backward dropping of frames from this port */
vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ARBITER, 0,
VSC73XX_SBACKWDROP, BIT(port), 0);
@@ -1036,6 +1029,89 @@ static void vsc73xx_phylink_get_caps(struct dsa_switch *dsa, int port,
config->mac_capabilities = MAC_SYM_PAUSE | MAC_10 | MAC_100 | MAC_1000;
}

+static void vsc73xx_refresh_fwd_map(struct dsa_switch *ds, int port, u8 state)
+{
+ struct dsa_port *other_dp, *dp = dsa_to_port(ds, port);
+ struct vsc73xx *vsc = ds->priv;
+ u16 mask;
+
+ if (state != BR_STATE_FORWARDING) {
+ /* Ports that aren't in the forwarding state must not
+ * forward packets anywhere.
+ */
+ vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ANALYZER, 0,
+ VSC73XX_SRCMASKS + port,
+ VSC73XX_SRCMASKS_PORTS_MASK, 0);
+
+ dsa_switch_for_each_available_port(other_dp, ds) {
+ if (other_dp == dp)
+ continue;
+ vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ANALYZER, 0,
+ VSC73XX_SRCMASKS + other_dp->index,
+ BIT(port), 0);
+ }
+
+ return;
+ }
+
+ /* Forwarding ports must forward to the CPU and to other ports
+ * in the same bridge
+ */
+ vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ANALYZER, 0,
+ VSC73XX_SRCMASKS + CPU_PORT, BIT(port), BIT(port));
+
+ mask = BIT(CPU_PORT);
+
+ if (dp->bridge) {
+ dsa_switch_for_each_user_port(other_dp, ds) {
+ if (other_dp->bridge == dp->bridge &&
+ other_dp->index != port &&
+ other_dp->stp_state == BR_STATE_FORWARDING) {
+ int other_port = other_dp->index;
+
+ mask |= BIT(other_port);
+ vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ANALYZER,
+ 0,
+ VSC73XX_SRCMASKS +
+ other_port,
+ BIT(port), BIT(port));
+ }
+ }
+ }
+
+ vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ANALYZER, 0,
+ VSC73XX_SRCMASKS + port,
+ VSC73XX_SRCMASKS_PORTS_MASK, mask);
+}
+
+/* FIXME: STP frames aren't forwarded at this moment. BPDU frames are
+ * forwarded only from and to PI/SI interface. For more info see chapter
+ * 2.7.1 (CPU Forwarding) in datasheet.
+ * This function is required for tag_8021q operations.
+ */
+static void vsc73xx_port_stp_state_set(struct dsa_switch *ds, int port,
+ u8 state)
+{
+ struct vsc73xx *vsc = ds->priv;
+ u32 val;
+
+ val = (state == BR_STATE_BLOCKING || state == BR_STATE_DISABLED) ?
+ 0 : BIT(port);
+ vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ANALYZER, 0,
+ VSC73XX_RECVMASK, BIT(port), val);
+
+ val = (state == BR_STATE_LEARNING || state == BR_STATE_FORWARDING) ?
+ BIT(port) : 0;
+ vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ANALYZER, 0,
+ VSC73XX_LEARNMASK, BIT(port), val);
+
+ /* CPU Port should always forward packets when user ports are forwarding
+ * so let's configure it from other ports only.
+ */
+ if (port != CPU_PORT)
+ vsc73xx_refresh_fwd_map(ds, port, state);
+}
+
static const struct dsa_switch_ops vsc73xx_ds_ops = {
.get_tag_protocol = vsc73xx_get_tag_protocol,
.setup = vsc73xx_setup,
@@ -1051,6 +1127,7 @@ static const struct dsa_switch_ops vsc73xx_ds_ops = {
.port_disable = vsc73xx_port_disable,
.port_change_mtu = vsc73xx_change_mtu,
.port_max_mtu = vsc73xx_get_max_mtu,
+ .port_stp_state_set = vsc73xx_port_stp_state_set,
.phylink_get_caps = vsc73xx_phylink_get_caps,
};

--
2.34.1