[TG3]: Set minimal hw interrupt mitigation.

Even though we do software interrupt mitigation
via NAPI, it still helps to have some minimal
hw assisted mitigation.

This helps, particularly, on systems where register
I/O overhead is much greater than the CPU horsepower.

For example, it helps on NUMA systems.  In such cases
the PIO overhead to disable interrupts for NAPI accounts
for the majority of the packet processing cost.  The
CPU is fast enough such that only a single packet is
processed by each NAPI poll call.

Thanks to Michael Chan for reviewing this patch.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/net/tg3.h b/drivers/net/tg3.h
index 44c65160a20f..993f84c93dc4 100644
--- a/drivers/net/tg3.h
+++ b/drivers/net/tg3.h
@@ -876,10 +876,12 @@
 #define  HOSTCC_STATUS_ERROR_ATTN        0x00000004
 #define HOSTCC_RXCOL_TICKS              0x00003c08
 #define  LOW_RXCOL_TICKS                 0x00000032
+#define  LOW_RXCOL_TICKS_CLRTCKS         0x00000014
 #define  DEFAULT_RXCOL_TICKS             0x00000048
 #define  HIGH_RXCOL_TICKS                0x00000096
 #define HOSTCC_TXCOL_TICKS              0x00003c0c
 #define  LOW_TXCOL_TICKS                 0x00000096
+#define  LOW_TXCOL_TICKS_CLRTCKS         0x00000048
 #define  DEFAULT_TXCOL_TICKS             0x0000012c
 #define  HIGH_TXCOL_TICKS                0x00000145
 #define HOSTCC_RXMAX_FRAMES             0x00003c10
@@ -892,8 +894,10 @@
 #define  HIGH_TXMAX_FRAMES               0x00000052
 #define HOSTCC_RXCOAL_TICK_INT          0x00003c18
 #define  DEFAULT_RXCOAL_TICK_INT         0x00000019
+#define  DEFAULT_RXCOAL_TICK_INT_CLRTCKS 0x00000014
 #define HOSTCC_TXCOAL_TICK_INT          0x00003c1c
 #define  DEFAULT_TXCOAL_TICK_INT         0x00000019
+#define  DEFAULT_TXCOAL_TICK_INT_CLRTCKS 0x00000014
 #define HOSTCC_RXCOAL_MAXF_INT          0x00003c20
 #define  DEFAULT_RXCOAL_MAXF_INT         0x00000005
 #define HOSTCC_TXCOAL_MAXF_INT          0x00003c24
@@ -2227,7 +2231,7 @@ struct tg3 {
 
 #define SST_25VF0X0_PAGE_SIZE           4098
 
-
+        struct ethtool_coalesce         coal;
 };
 
 #endif /* !(_T3_H) */