ath5k: optimize tx descriptor setup

Use local variables to reduce the number of load/store operations on uncached
memory.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 20 insertions, 18 deletions

diff --git a/drivers/net/wireless/ath/ath5k/desc.c b/drivers/net/wireless/ath/ath5k/desc.c
index 16b44ff7dd3..0a8a9efaf8b 100644
--- a/drivers/net/wireless/ath/ath5k/desc.c
+++ b/drivers/net/wireless/ath/ath5k/desc.c
@@ -184,6 +184,7 @@ static int ath5k_hw_setup_4word_tx_desc(struct ath5k_hw *ah,
 {
         struct ath5k_hw_4w_tx_ctl *tx_ctl;
         unsigned int frame_len;
+        u32 txctl0 = 0, txctl1 = 0, txctl2 = 0, txctl3 = 0;
 
         tx_ctl = &desc->ud.ds_tx5212.tx_ctl;
 
@@ -209,7 +210,8 @@ static int ath5k_hw_setup_4word_tx_desc(struct ath5k_hw *ah,
                 tx_power = AR5K_TUNE_MAX_TXPOWER;
 
         /* Clear descriptor */
-        memset(&desc->ud.ds_tx5212, 0, sizeof(struct ath5k_hw_5212_tx_desc));
+        memset(&desc->ud.ds_tx5212.tx_stat, 0,
+               sizeof(desc->ud.ds_tx5212.tx_stat));
 
         /* Setup control descriptor */
 
@@ -221,7 +223,7 @@ static int ath5k_hw_setup_4word_tx_desc(struct ath5k_hw *ah,
         if (frame_len & ~AR5K_4W_TX_DESC_CTL0_FRAME_LEN)
                 return -EINVAL;
 
-        tx_ctl->tx_control_0 = frame_len & AR5K_4W_TX_DESC_CTL0_FRAME_LEN;
+        txctl0 = frame_len & AR5K_4W_TX_DESC_CTL0_FRAME_LEN;
 
         /* Verify and set buffer length */
 
@@ -232,21 +234,17 @@ static int ath5k_hw_setup_4word_tx_desc(struct ath5k_hw *ah,
         if (pkt_len & ~AR5K_4W_TX_DESC_CTL1_BUF_LEN)
                 return -EINVAL;
 
-        tx_ctl->tx_control_1 = pkt_len & AR5K_4W_TX_DESC_CTL1_BUF_LEN;
+        txctl1 = pkt_len & AR5K_4W_TX_DESC_CTL1_BUF_LEN;
 
-        tx_ctl->tx_control_0 |=
-                AR5K_REG_SM(tx_power, AR5K_4W_TX_DESC_CTL0_XMIT_POWER) |
-                AR5K_REG_SM(antenna_mode, AR5K_4W_TX_DESC_CTL0_ANT_MODE_XMIT);
-        tx_ctl->tx_control_1 |= AR5K_REG_SM(type,
-                                        AR5K_4W_TX_DESC_CTL1_FRAME_TYPE);
-        tx_ctl->tx_control_2 = AR5K_REG_SM(tx_tries0,
-                                        AR5K_4W_TX_DESC_CTL2_XMIT_TRIES0);
-        tx_ctl->tx_control_3 = tx_rate0 & AR5K_4W_TX_DESC_CTL3_XMIT_RATE0;
+        txctl0 |= AR5K_REG_SM(tx_power, AR5K_4W_TX_DESC_CTL0_XMIT_POWER) |
+                  AR5K_REG_SM(antenna_mode, AR5K_4W_TX_DESC_CTL0_ANT_MODE_XMIT);
+        txctl1 |= AR5K_REG_SM(type, AR5K_4W_TX_DESC_CTL1_FRAME_TYPE);
+        txctl2 = AR5K_REG_SM(tx_tries0, AR5K_4W_TX_DESC_CTL2_XMIT_TRIES0);
+        txctl3 = tx_rate0 & AR5K_4W_TX_DESC_CTL3_XMIT_RATE0;
 
 #define _TX_FLAGS(_c, _flag)                                    \
         if (flags & AR5K_TXDESC_##_flag) {                      \
-                tx_ctl->tx_control_##_c |=                      \
-                        AR5K_4W_TX_DESC_CTL##_c##_##_flag;      \
+                txctl##_c |= AR5K_4W_TX_DESC_CTL##_c##_##_flag; \
         }
 
         _TX_FLAGS(0, CLRDMASK);
@@ -262,8 +260,8 @@ static int ath5k_hw_setup_4word_tx_desc(struct ath5k_hw *ah,
          * WEP crap
          */
         if (key_index != AR5K_TXKEYIX_INVALID) {
-                tx_ctl->tx_control_0 |= AR5K_4W_TX_DESC_CTL0_ENCRYPT_KEY_VALID;
-                tx_ctl->tx_control_1 |= AR5K_REG_SM(key_index,
+                txctl0 |= AR5K_4W_TX_DESC_CTL0_ENCRYPT_KEY_VALID;
+                txctl1 |= AR5K_REG_SM(key_index,
                                 AR5K_4W_TX_DESC_CTL1_ENCRYPT_KEY_IDX);
         }
 
@@ -274,12 +272,16 @@ static int ath5k_hw_setup_4word_tx_desc(struct ath5k_hw *ah,
                 if ((flags & AR5K_TXDESC_RTSENA) &&
                                 (flags & AR5K_TXDESC_CTSENA))
                         return -EINVAL;
-                tx_ctl->tx_control_2 |= rtscts_duration &
-                                AR5K_4W_TX_DESC_CTL2_RTS_DURATION;
-                tx_ctl->tx_control_3 |= AR5K_REG_SM(rtscts_rate,
+                txctl2 |= rtscts_duration & AR5K_4W_TX_DESC_CTL2_RTS_DURATION;
+                txctl3 |= AR5K_REG_SM(rtscts_rate,
                                 AR5K_4W_TX_DESC_CTL3_RTS_CTS_RATE);
         }
 
+        tx_ctl->tx_control_0 = txctl0;
+        tx_ctl->tx_control_1 = txctl1;
+        tx_ctl->tx_control_2 = txctl2;
+        tx_ctl->tx_control_3 = txctl3;
+
         return 0;
 }