openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

ath5k: improve comments for optimized tx descriptor setup 

Comment the use of local variables to reduce the number of load/store
operations on uncached memory, in hopes of not losing this optimization
accidentally in the future.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
John W. Linville 2011-04-13 08:47:32 -04:00
parent 6f11c819d5
commit 8962d87129
1 changed files with 6 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
drivers/net/wireless/ath/ath5k/desc.c
View File

@ -184,6 +184,11 @@ static int ath5k_hw_setup_4word_tx_desc(struct ath5k_hw *ah,
{ {
struct ath5k_hw_4w_tx_ctl *tx_ctl; struct ath5k_hw_4w_tx_ctl *tx_ctl;
unsigned int frame_len; unsigned int frame_len;
/*
* Use local variables for these to reduce load/store access on
* uncached memory
*/
u32 txctl0 = 0, txctl1 = 0, txctl2 = 0, txctl3 = 0; u32 txctl0 = 0, txctl1 = 0, txctl2 = 0, txctl3 = 0;
tx_ctl = &desc->ud.ds_tx5212.tx_ctl; tx_ctl = &desc->ud.ds_tx5212.tx_ctl;
@ -209,7 +214,7 @@ static int ath5k_hw_setup_4word_tx_desc(struct ath5k_hw *ah,
if (tx_power > AR5K_TUNE_MAX_TXPOWER) if (tx_power > AR5K_TUNE_MAX_TXPOWER)
tx_power = AR5K_TUNE_MAX_TXPOWER; tx_power = AR5K_TUNE_MAX_TXPOWER;
/* Clear descriptor */ /* Clear descriptor status area */
memset(&desc->ud.ds_tx5212.tx_stat, 0, memset(&desc->ud.ds_tx5212.tx_stat, 0,
sizeof(desc->ud.ds_tx5212.tx_stat)); sizeof(desc->ud.ds_tx5212.tx_stat));