[PATCH 5.13 092/151] net: dsa: microchip: ksz8795: Fix PVID tag insertion

Greg Kroah-Hartman
2021-08-16T13:26:51Z

From: Ben Hutchings <ben.hutchings@mind.be>

[ Upstream commit ef3b02a1d79b691f9a354c4903cf1e6917e315f9 ]

ksz8795 has never actually enabled PVID tag insertion, and it also
programmed the PVID incorrectly. To fix this:

* Allow tag insertion to be controlled per ingress port. On most
chips, set bit 2 in Global Control 19. On KSZ88x3 this control
flag doesn't exist.

* When adding a PVID:
- Set the appropriate register bits to enable tag insertion on
egress at every other port if this was the packet's ingress port.
- Mask *out* the VID from the default tag, before or-ing in the new
PVID.

* When removing a PVID:
- Clear the same control bits to disable tag insertion.
- Don't update the default tag. This wasn't doing anything useful.

Fixes: e66f840c08a2 ("net: dsa: ksz: Add Microchip KSZ8795 DSA driver")
Signed-off-by: Ben Hutchings <ben.hutchings@mind.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/dsa/microchip/ksz8795.c | 26 ++++++++++++++++++-------
drivers/net/dsa/microchip/ksz8795_reg.h | 4 ++++
2 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz8795.c b/drivers/net/dsa/microchip/ksz8795.c
index ad509a57a945..bc9ca2b0e091 100644
--- a/drivers/net/dsa/microchip/ksz8795.c
+++ b/drivers/net/dsa/microchip/ksz8795.c
@@ -1083,6 +1083,16 @@ static int ksz8_port_vlan_filtering(struct dsa_switch *ds, int port, bool flag,
return 0;
}

+static void ksz8_port_enable_pvid(struct ksz_device *dev, int port, bool state)
+{
+ if (ksz_is_ksz88x3(dev)) {
+ ksz_cfg(dev, REG_SW_INSERT_SRC_PVID,
+ 0x03 << (4 - 2 * port), state);
+ } else {
+ ksz_pwrite8(dev, port, REG_PORT_CTRL_12, state ? 0x0f : 0x00);
+ }
+}
+
static int ksz8_port_vlan_add(struct dsa_switch *ds, int port,
const struct switchdev_obj_port_vlan *vlan,
struct netlink_ext_ack *extack)
@@ -1119,9 +1129,11 @@ static int ksz8_port_vlan_add(struct dsa_switch *ds, int port,
u16 vid;

ksz_pread16(dev, port, REG_PORT_CTRL_VID, &vid);
- vid &= 0xfff;
+ vid &= ~VLAN_VID_MASK;
vid |= new_pvid;
ksz_pwrite16(dev, port, REG_PORT_CTRL_VID, vid);
+
+ ksz8_port_enable_pvid(dev, port, true);
}

return 0;
@@ -1132,7 +1144,7 @@ static int ksz8_port_vlan_del(struct dsa_switch *ds, int port,
{
bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
struct ksz_device *dev = ds->priv;
- u16 data, pvid, new_pvid = 0;
+ u16 data, pvid;
u8 fid, member, valid;

if (ksz_is_ksz88x3(dev))
@@ -1154,14 +1166,11 @@ static int ksz8_port_vlan_del(struct dsa_switch *ds, int port,
valid = 0;
}

- if (pvid == vlan->vid)
- new_pvid = 1;
-
ksz8_to_vlan(dev, fid, member, valid, &data);
ksz8_w_vlan_table(dev, vlan->vid, data);

- if (new_pvid != pvid)
- ksz_pwrite16(dev, port, REG_PORT_CTRL_VID, pvid);
+ if (pvid == vlan->vid)
+ ksz8_port_enable_pvid(dev, port, false);

return 0;
}
@@ -1394,6 +1403,9 @@ static int ksz8_setup(struct dsa_switch *ds)

ksz_cfg(dev, S_MIRROR_CTRL, SW_MIRROR_RX_TX, false);

+ if (!ksz_is_ksz88x3(dev))
+ ksz_cfg(dev, REG_SW_CTRL_19, SW_INS_TAG_ENABLE, true);
+
/* set broadcast storm protection 10% rate */
regmap_update_bits(dev->regmap[1], S_REPLACE_VID_CTRL,
BROADCAST_STORM_RATE,
diff --git a/drivers/net/dsa/microchip/ksz8795_reg.h b/drivers/net/dsa/microchip/ksz8795_reg.h
index c2e52c40a54c..383ba7a90f9c 100644
--- a/drivers/net/dsa/microchip/ksz8795_reg.h
+++ b/drivers/net/dsa/microchip/ksz8795_reg.h
@@ -631,6 +631,10 @@
#define REG_PORT_4_OUT_RATE_3 0xEE
#define REG_PORT_5_OUT_RATE_3 0xFE

+/* 88x3 specific */
+
+#define REG_SW_INSERT_SRC_PVID 0xC2
+
/* PME */

#define SW_PME_OUTPUT_ENABLE BIT(1)
--
2.30.2