From: Vladimir Oltean <vladimir.oltean@xxxxxxx>
[ Upstream commit 49753a75b9a32de4c0393bb8d1e51ea223fda8e4 ]
Looking at the code, the GSWIP switch appears to hold bridging service
structures (VLANs, FDBs, forwarding rules) in PCE table entries.
Hardware access to the PCE table is non-atomic, and is comprised of
several register reads and writes.
These accesses are currently serialized by the rtnl_lock, but DSA is
changing its driver API and that lock will no longer be held when
calling ->port_fdb_add() and ->port_fdb_del().
So this driver needs to serialize the access to the PCE table using its
own locking scheme. This patch adds that.
Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Acked-by: Hauke Mehrtens <hauke@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/dsa/lantiq_gswip.c | 28 +++++++++++++++++++++++-----
1 file changed, 23 insertions(+), 5 deletions(-)
diff --git a/drivers/net/dsa/lantiq_gswip.c b/drivers/net/dsa/lantiq_gswip.c
index 4d23a7aba7961..f54e7f48b0dd7 100644
--- a/drivers/net/dsa/lantiq_gswip.c
+++ b/drivers/net/dsa/lantiq_gswip.c
@@ -274,6 +274,7 @@ struct gswip_priv {
int num_gphy_fw;
struct gswip_gphy_fw *gphy_fw;
u32 port_vlan_filter;
+ struct mutex pce_table_lock;
};
struct gswip_pce_table_entry {
@@ -521,10 +522,14 @@ static int gswip_pce_table_entry_read(struct gswip_priv *priv,
u16 addr_mode = tbl->key_mode ? GSWIP_PCE_TBL_CTRL_OPMOD_KSRD :
GSWIP_PCE_TBL_CTRL_OPMOD_ADRD;
+ mutex_lock(&priv->pce_table_lock);
+
err = gswip_switch_r_timeout(priv, GSWIP_PCE_TBL_CTRL,
GSWIP_PCE_TBL_CTRL_BAS);
- if (err)
+ if (err) {
+ mutex_unlock(&priv->pce_table_lock);
return err;
+ }
gswip_switch_w(priv, tbl->index, GSWIP_PCE_TBL_ADDR);
gswip_switch_mask(priv, GSWIP_PCE_TBL_CTRL_ADDR_MASK |
@@ -534,8 +539,10 @@ static int gswip_pce_table_entry_read(struct gswip_priv *priv,
err = gswip_switch_r_timeout(priv, GSWIP_PCE_TBL_CTRL,
GSWIP_PCE_TBL_CTRL_BAS);
- if (err)
+ if (err) {
+ mutex_unlock(&priv->pce_table_lock);
return err;
+ }
for (i = 0; i < ARRAY_SIZE(tbl->key); i++)
tbl->key[i] = gswip_switch_r(priv, GSWIP_PCE_TBL_KEY(i));
@@ -551,6 +558,8 @@ static int gswip_pce_table_entry_read(struct gswip_priv *priv,
tbl->valid = !!(crtl & GSWIP_PCE_TBL_CTRL_VLD);
tbl->gmap = (crtl & GSWIP_PCE_TBL_CTRL_GMAP_MASK) >> 7;
+ mutex_unlock(&priv->pce_table_lock);
+
return 0;
}
@@ -563,10 +572,14 @@ static int gswip_pce_table_entry_write(struct gswip_priv *priv,
u16 addr_mode = tbl->key_mode ? GSWIP_PCE_TBL_CTRL_OPMOD_KSWR :
GSWIP_PCE_TBL_CTRL_OPMOD_ADWR;
+ mutex_lock(&priv->pce_table_lock);
+
err = gswip_switch_r_timeout(priv, GSWIP_PCE_TBL_CTRL,
GSWIP_PCE_TBL_CTRL_BAS);
- if (err)
+ if (err) {
+ mutex_unlock(&priv->pce_table_lock);
return err;
+ }
gswip_switch_w(priv, tbl->index, GSWIP_PCE_TBL_ADDR);
gswip_switch_mask(priv, GSWIP_PCE_TBL_CTRL_ADDR_MASK |
@@ -598,8 +611,12 @@ static int gswip_pce_table_entry_write(struct gswip_priv *priv,
crtl |= GSWIP_PCE_TBL_CTRL_BAS;
gswip_switch_w(priv, crtl, GSWIP_PCE_TBL_CTRL);
- return gswip_switch_r_timeout(priv, GSWIP_PCE_TBL_CTRL,
- GSWIP_PCE_TBL_CTRL_BAS);
+ err = gswip_switch_r_timeout(priv, GSWIP_PCE_TBL_CTRL,
+ GSWIP_PCE_TBL_CTRL_BAS);
+
+ mutex_unlock(&priv->pce_table_lock);
+
+ return err;
}
/* Add the LAN port into a bridge with the CPU port by
@@ -2040,6 +2057,7 @@ static int gswip_probe(struct platform_device *pdev)
priv->ds->priv = priv;
priv->ds->ops = &gswip_switch_ops;
priv->dev = dev;
+ mutex_init(&priv->pce_table_lock);
version = gswip_switch_r(priv, GSWIP_VERSION);
/* bring up the mdio bus */
--
2.33.0
