cxgb4 : Handle dcb enable correctly

Disabling DCBx in firmware automatically enables DCBx for control via host
lldp agents. Wait for an explicit setstate call from an lldp agents to enable
 DCBx instead.

Fixes: 76bcb31efc06 ("cxgb4 : Add DCBx support codebase and dcbnl_ops")

Signed-off-by: Anish Bhatt <anish@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c
index ee819fd..6fe300e 100644 (file)
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_dcb.c
@@ -116,7 +116,6 @@ void cxgb4_dcb_state_fsm(struct net_device *dev,
                        /* we're going to use Host DCB */
                        dcb->state = CXGB4_DCB_STATE_HOST;
                        dcb->supported = CXGB4_DCBX_HOST_SUPPORT;
-                       dcb->enabled = 1;
                        break;
                }
 
@@ -386,6 +385,12 @@ static u8 cxgb4_setstate(struct net_device *dev, u8 enabled)
 {
        struct port_info *pi = netdev2pinfo(dev);
 
+       /* If DCBx is host-managed, dcb is enabled by outside lldp agents */
+       if (pi->dcb.state == CXGB4_DCB_STATE_HOST) {
+               pi->dcb.enabled = enabled;
+               return 0;
+       }
+
        /* Firmware doesn't provide any mechanism to control the DCB state.
         */
        if (enabled != (pi->dcb.state == CXGB4_DCB_STATE_FW_ALLSYNCED))

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
index 3f60070..97683c1 100644 (file)
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
@@ -694,7 +694,11 @@ int cxgb4_dcb_enabled(const struct net_device *dev)
 #ifdef CONFIG_CHELSIO_T4_DCB
        struct port_info *pi = netdev_priv(dev);
 
-       return pi->dcb.state == CXGB4_DCB_STATE_FW_ALLSYNCED;
+       if (!pi->dcb.enabled)
+               return 0;
+
+       return ((pi->dcb.state == CXGB4_DCB_STATE_FW_ALLSYNCED) ||
+               (pi->dcb.state == CXGB4_DCB_STATE_HOST));
 #else
        return 0;
 #endif