i40e: Fix configure TCs after initial DCB disable

in commit a036244c068612a43fa8c0f33a0eb4daa4d8dba0 a fix
was put into place to avoid a kernel panic when a non-
supported traffic class configuration was put into place
and then lldp was enabled/disabled on the link partner
switch.  This fix caused it to be necessary to
unload/reload the driver to reenable DCB once a supported
TC config was in place.

The root cause of the original panic was that the function
i40e_pf_get_default_tc was allowing for a default TC other
than TC 0, and only TC 0 is supported as a default.

This patch removes the get_default_tc function and replaces
it with a #define since there is only one TC supported as
a default.

Change-Id: I448371974e946386d0a7718d73668b450b7c72ef
Signed-off-by: Dave Ertman <david.m.ertman@intel.com>
Tested-by: Ronald Bynoe <ronald.j.bynoe@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

2 files changed, 5 insertions, 27 deletions

diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index 2030d7c1dc94..6d61e443bdf8 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -92,6 +92,7 @@
 #define I40E_AQ_LEN                     256
 #define I40E_AQ_WORK_LIMIT              66 /* max number of VFs + a little */
 #define I40E_MAX_USER_PRIORITY          8
+#define I40E_DEFAULT_TRAFFIC_CLASS      BIT(0)
 #define I40E_DEFAULT_MSG_ENABLE         4
 #define I40E_QUEUE_WAIT_RETRY_LIMIT     10
 #define I40E_INT_NAME_STR_LEN           (IFNAMSIZ + 16)
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index ac1faee2a5b8..050d005d2ede 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -4641,29 +4641,6 @@ static u8 i40e_pf_get_num_tc(struct i40e_pf *pf)
 }
 
 /**
- * i40e_pf_get_default_tc - Get bitmap for first enabled TC
- * @pf: PF being queried
- *
- * Return a bitmap for first enabled traffic class for this PF.
- **/
-static u8 i40e_pf_get_default_tc(struct i40e_pf *pf)
-{
-        u8 enabled_tc = pf->hw.func_caps.enabled_tcmap;
-        u8 i = 0;
-
-        if (!enabled_tc)
-                return 0x1; /* TC0 */
-
-        /* Find the first enabled TC */
-        for (i = 0; i < I40E_MAX_TRAFFIC_CLASS; i++) {
-                if (enabled_tc & BIT(i))
-                        break;
-        }
-
-        return BIT(i);
-}
-
-/**
  * i40e_pf_get_pf_tc_map - Get bitmap for enabled traffic classes
  * @pf: PF being queried
  *
@@ -4673,7 +4650,7 @@ static u8 i40e_pf_get_tc_map(struct i40e_pf *pf)
 {
         /* If DCB is not enabled for this PF then just return default TC */
         if (!(pf->flags & I40E_FLAG_DCB_ENABLED))
-                return i40e_pf_get_default_tc(pf);
+                return I40E_DEFAULT_TRAFFIC_CLASS;
 
         /* SFP mode we want PF to be enabled for all TCs */
         if (!(pf->flags & I40E_FLAG_MFP_ENABLED))
@@ -4683,7 +4660,7 @@ static u8 i40e_pf_get_tc_map(struct i40e_pf *pf)
         if (pf->hw.func_caps.iscsi)
                 return i40e_get_iscsi_tc_map(pf);
         else
-                return i40e_pf_get_default_tc(pf);
+                return I40E_DEFAULT_TRAFFIC_CLASS;
 }
 
 /**
@@ -5029,7 +5006,7 @@ static void i40e_dcb_reconfigure(struct i40e_pf *pf)
                 if (v == pf->lan_vsi)
                         tc_map = i40e_pf_get_tc_map(pf);
                 else
-                        tc_map = i40e_pf_get_default_tc(pf);
+                        tc_map = I40E_DEFAULT_TRAFFIC_CLASS;
 #ifdef I40E_FCOE
                 if (pf->vsi[v]->type == I40E_VSI_FCOE)
                         tc_map = i40e_get_fcoe_tc_map(pf);
@@ -5717,7 +5694,7 @@ static int i40e_handle_lldp_event(struct i40e_pf *pf,
         u8 type;
 
         /* Not DCB capable or capability disabled */
-        if (!(pf->flags & I40E_FLAG_DCB_ENABLED))
+        if (!(pf->flags & I40E_FLAG_DCB_CAPABLE))
                 return ret;
 
         /* Ignore if event is not for Nearest Bridge */