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 excessiv

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>

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e1000e: workaround DMA unit hang on I218

At 1000Mbps link speed, one of the MAC's internal clocks can be stopped for
up to 4us when entering K1 (a power mode of the MAC-PHY interconnect)

e1000e: workaround DMA unit hang on I218

At 1000Mbps link speed, one of the MAC's internal clocks can be stopped for
up to 4us when entering K1 (a power mode of the MAC-PHY interconnect). If
the MAC is waiting for completion indications for 2 DMA write requests into
Host memory (e.g. descriptor writeback or Rx packet writing) and the
indications occur while the clock is stopped, both indications will be
missed by the MAC causing the MAC to wait for the completion indications
and be unable to generate further DMA write requests. This results in an
apparent hardware hang.

Work-around the issue by disabling the de-assertion of the clock request
when 1000Mbps link is acquired (K1 must be disabled while doing this).

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>

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e1000e: cosmetic move of #defines and prototypes to the new ich8lan.h

Move #defines and function prototypes specific to the ICH/PCH family of
devices (ICH8/82562, ICH8/82566, ICH8/82567,

e1000e: cosmetic move of #defines and prototypes to the new ich8lan.h

Move #defines and function prototypes specific to the ICH/PCH family of
devices (ICH8/82562, ICH8/82566, ICH8/82567, ICH9/82562, ICH9/82566,
ICH9/82567, ICH10/82567, 82577, 82578, 82579, I217, I218) to the new
ich8lan.h header file (the convention for Intel wired ethernet drivers is
to use the name of the first device in the family for related file and
function names). These defines and function prototypes can be used by
other files in the driver and moving them to the ICH/PCH-family-specific
file makes it clearer to which devices they are applicable.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

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