For mac revisions >= "Griffin," the hardware allows the mic tx and rx
authenticator keys to share the same cache line, whereas earlier
hardware can only store the rx.  Enable the combined mic on hardware
that supports it.
Changes to ath5k.h
Changes-licensed-under: 3-Clause-BSD
Changes to attach.c, pcu.c, reg.h
Changes-licensed-under: ISC
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
        bool                    ah_calibration;
        bool                    ah_running;
        bool                    ah_single_chip;
+       bool                    ah_combined_mic;
        enum ath5k_rfgain       ah_rf_gain;
 
        u32                     ah_mac_srev;
 
                goto err_free;
        }
 
+       if (srev >= AR5K_SREV_AR2414) {
+               ah->ah_combined_mic = true;
+               AR5K_REG_ENABLE_BITS(ah, AR5K_MISC_MODE,
+                       AR5K_MISC_MODE_COMBINED_MIC);
+       }
+
        /* MAC address is cleared until add_interface */
        ath5k_hw_set_lladdr(ah, mac);
 
 
                /* Install rx/tx MIC */
                rxmic = (__le32 *) &key->key[16];
                txmic = (__le32 *) &key->key[24];
-#if 0
-               /* MISC_MODE register & 0x04 - for mac srev >= griffin */
-               key_v[0] = rxmic[0];
-               key_v[1] = (txmic[0] >> 16) & 0xffff;
-               key_v[2] = rxmic[1];
-               key_v[3] = txmic[0] & 0xffff;
-               key_v[4] = txmic[1];
-#else
-               key_v[0] = rxmic[0];
-               key_v[1] = 0;
-               key_v[2] = rxmic[1];
-               key_v[3] = 0;
-               key_v[4] = 0;
-#endif
+
+               if (ah->ah_combined_mic) {
+                       key_v[0] = rxmic[0];
+                       key_v[1] = (txmic[0] >> 16) & 0xffff;
+                       key_v[2] = rxmic[1];
+                       key_v[3] = txmic[0] & 0xffff;
+                       key_v[4] = txmic[1];
+               } else {
+                       key_v[0] = rxmic[0];
+                       key_v[1] = 0;
+                       key_v[2] = rxmic[1];
+                       key_v[3] = 0;
+                       key_v[4] = 0;
+               }
                for (i = 0; i < ARRAY_SIZE(key_v); i++)
                        ath5k_hw_reg_write(ah, le32_to_cpu(key_v[i]),
                                AR5K_KEYTABLE_OFF(micentry, i));
 
 #define        AR5K_MISC_MODE                  0x8120                  /* Register Address */
 #define        AR5K_MISC_MODE_FBSSID_MATCH     0x00000001      /* Force BSSID match */
 #define        AR5K_MISC_MODE_ACKSIFS_MEM      0x00000002      /* ACK SIFS memory (?) */
+#define        AR5K_MISC_MODE_COMBINED_MIC     0x00000004      /* use rx/tx MIC key */
 /* more bits */
 
 /*