diff options
| author | Bruce Allan <bruce.w.allan@intel.com> | 2013-03-06 13:02:36 +0400 |
|---|---|---|
| committer | Jeff Kirsher <jeffrey.t.kirsher@intel.com> | 2013-03-28 10:25:36 +0400 |
| commit | 772d05c51c4f4896c120ad418b1e91144a2ac813 (patch) | |
| tree | 0c67bd6877d7c121030d34d1de86832c807d2d53 /drivers/net/ethernet/intel/e1000e/defines.h | |
| parent | bb034512da74dce901f738f7c7cea332ff971608 (diff) | |
| download | linux-772d05c51c4f4896c120ad418b1e91144a2ac813.tar.xz | |
e1000e: slow performance between two 82579 connected via 10Mbit hub
Two 82579 LOMs connected via a 10Mb hub experience extraordinarily low
performance. This is because 82579 is excessively aggressive on transmit
at 10Mb half-duplex and will not provide sufficient time for the link
partner to transmit. When the link partner is also 82579, the result is a
lot of collisions (and corresponding re-transmits) that cause the poor
performance. To work-around this issue, significantly increase the IPG in
the MAC to allow enough gap for the link partner to transmit and reduce the
Rx latency in the analog PHY to 0 to reduce the number of collisions.
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Jeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Diffstat (limited to 'drivers/net/ethernet/intel/e1000e/defines.h')
| -rw-r--r-- | drivers/net/ethernet/intel/e1000e/defines.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/net/ethernet/intel/e1000e/defines.h b/drivers/net/ethernet/intel/e1000e/defines.h index a6aeb195390f..351c94a0cf74 100644 --- a/drivers/net/ethernet/intel/e1000e/defines.h +++ b/drivers/net/ethernet/intel/e1000e/defines.h @@ -236,6 +236,7 @@ #define E1000_STATUS_FUNC_SHIFT 2 #define E1000_STATUS_FUNC_1 0x00000004 /* Function 1 */ #define E1000_STATUS_TXOFF 0x00000010 /* transmission paused */ +#define E1000_STATUS_SPEED_MASK 0x000000C0 #define E1000_STATUS_SPEED_10 0x00000000 /* Speed 10Mb/s */ #define E1000_STATUS_SPEED_100 0x00000040 /* Speed 100Mb/s */ #define E1000_STATUS_SPEED_1000 0x00000080 /* Speed 1000Mb/s */ |