ath5k: enable combined michael mic in key cache

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>

4 files changed, 22 insertions, 14 deletions

diff --git a/drivers/net/wireless/ath5k/ath5k.h b/drivers/net/wireless/ath5k/ath5k.h
index 5ee2dd1814c2..13df1191b070 100644
--- a/drivers/net/wireless/ath5k/ath5k.h
+++ b/drivers/net/wireless/ath5k/ath5k.h
@@ -1052,6 +1052,7 @@ struct ath5k_hw {
         bool                    ah_calibration;
         bool                    ah_running;
         bool                    ah_single_chip;
+        bool                    ah_combined_mic;
         enum ath5k_rfgain       ah_rf_gain;
 
         u32                     ah_mac_srev;
diff --git a/drivers/net/wireless/ath5k/attach.c b/drivers/net/wireless/ath5k/attach.c
index 49d82d79d3fc..dea378f76731 100644
--- a/drivers/net/wireless/ath5k/attach.c
+++ b/drivers/net/wireless/ath5k/attach.c
@@ -317,6 +317,12 @@ struct ath5k_hw *ath5k_hw_attach(struct ath5k_softc *sc, u8 mac_version)
                 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);
 
diff --git a/drivers/net/wireless/ath5k/pcu.c b/drivers/net/wireless/ath5k/pcu.c
index ad7ea36502bd..dabe42219e2a 100644
--- a/drivers/net/wireless/ath5k/pcu.c
+++ b/drivers/net/wireless/ath5k/pcu.c
@@ -1096,20 +1096,20 @@ int ath5k_hw_set_key(struct ath5k_hw *ah, u16 entry,
                 /* 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));
diff --git a/drivers/net/wireless/ath5k/reg.h b/drivers/net/wireless/ath5k/reg.h
index 69755fc2f9be..91aaeaf88199 100644
--- a/drivers/net/wireless/ath5k/reg.h
+++ b/drivers/net/wireless/ath5k/reg.h
@@ -1729,6 +1729,7 @@
 #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 */
 
 /*