Merge tag 'drm/tegra/for-4.8-rc4' of git://anongit.freedesktop.org/tegra/linux into...

[cascardo/linux.git] / drivers / net / ethernet / intel / i40e / i40e_main.c

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 81c99e1..c6ac7a6 100644 (file)
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -4554,23 +4554,38 @@ static u8 i40e_get_iscsi_tc_map(struct i40e_pf *pf)
  **/
 static u8 i40e_dcb_get_num_tc(struct i40e_dcbx_config *dcbcfg)
 {
+       int i, tc_unused = 0;
        u8 num_tc = 0;
-       int i;
+       u8 ret = 0;
 
        /* Scan the ETS Config Priority Table to find
         * traffic class enabled for a given priority
-        * and use the traffic class index to get the
-        * number of traffic classes enabled
+        * and create a bitmask of enabled TCs
         */
-       for (i = 0; i < I40E_MAX_USER_PRIORITY; i++) {
-               if (dcbcfg->etscfg.prioritytable[i] > num_tc)
-                       num_tc = dcbcfg->etscfg.prioritytable[i];
-       }
+       for (i = 0; i < I40E_MAX_USER_PRIORITY; i++)
+               num_tc |= BIT(dcbcfg->etscfg.prioritytable[i]);
 
-       /* Traffic class index starts from zero so
-        * increment to return the actual count
+       /* Now scan the bitmask to check for
+        * contiguous TCs starting with TC0
         */
-       return num_tc + 1;
+       for (i = 0; i < I40E_MAX_TRAFFIC_CLASS; i++) {
+               if (num_tc & BIT(i)) {
+                       if (!tc_unused) {
+                               ret++;
+                       } else {
+                               pr_err("Non-contiguous TC - Disabling DCB\n");
+                               return 1;
+                       }
+               } else {
+                       tc_unused = 1;
+               }
+       }
+
+       /* There is always at least TC0 */
+       if (!ret)
+               ret = 1;
+
+       return ret;
 }
 
 /**