mv643xx_eth: use longer DMA bursts
authorLennert Buytenhek <buytenh@wantstofly.org>
Thu, 10 Jul 2008 12:40:51 +0000 (14:40 +0200)
committerLennert Buytenhek <buytenh@marvell.com>
Thu, 24 Jul 2008 04:22:51 +0000 (06:22 +0200)
The mv643xx_eth driver is limiting DMA bursts to 32 bytes, while
using the largest burst size (128 bytes) gives a couple percentage
points performance improvement in throughput tests, and the docs
say that the 128 byte default should not need to be changed, so
use 128 byte bursts instead.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
drivers/net/mv643xx_eth.c

index c700c1f494e993a8b86b73f92986533af7f15052..9d200568d88a3b95a72c568c12b71ce3bb49c6e6 100644 (file)
@@ -129,21 +129,21 @@ static char mv643xx_eth_driver_version[] = "1.1";
 /*
  * SDMA configuration register.
  */
-#define RX_BURST_SIZE_4_64BIT          (2 << 1)
+#define RX_BURST_SIZE_16_64BIT         (4 << 1)
 #define BLM_RX_NO_SWAP                 (1 << 4)
 #define BLM_TX_NO_SWAP                 (1 << 5)
-#define TX_BURST_SIZE_4_64BIT          (2 << 22)
+#define TX_BURST_SIZE_16_64BIT         (4 << 22)
 
 #if defined(__BIG_ENDIAN)
 #define PORT_SDMA_CONFIG_DEFAULT_VALUE         \
-               RX_BURST_SIZE_4_64BIT   |       \
-               TX_BURST_SIZE_4_64BIT
+               RX_BURST_SIZE_16_64BIT  |       \
+               TX_BURST_SIZE_16_64BIT
 #elif defined(__LITTLE_ENDIAN)
 #define PORT_SDMA_CONFIG_DEFAULT_VALUE         \
-               RX_BURST_SIZE_4_64BIT   |       \
+               RX_BURST_SIZE_16_64BIT  |       \
                BLM_RX_NO_SWAP          |       \
                BLM_TX_NO_SWAP          |       \
-               TX_BURST_SIZE_4_64BIT
+               TX_BURST_SIZE_16_64BIT
 #else
 #error One of __BIG_ENDIAN or __LITTLE_ENDIAN must be defined
 #endif