Commit 228046e7 authored by Jeff Kirsher's avatar Jeff Kirsher
Browse files

Documentation: e1000: Update kernel documentation 



Updated the e1000.txt kernel documentation with the latest information.

Also convert the text file to reStructuredText (RST) format, since the
Linux kernel documentation now uses this format for documentation.

Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
Tested-by: default avatarAaron Brown <aaron.f.brown@intel.com>
parent 85d63445

Documentation/networking/e1000.txt→Documentation/networking/e1000.rst

+10 −49
Original line number Original line Diff line number Diff line
@@ -154,7 +154,7 @@ NOTE: When e1000 is loaded with default settings and multiple adapters 
       are in use simultaneously, the CPU utilization may increase non-

       are in use simultaneously, the CPU utilization may increase non-

       linearly.  In order to limit the CPU utilization without impacting

       linearly.  In order to limit the CPU utilization without impacting

       the overall throughput, we recommend that you load the driver as

       the overall throughput, we recommend that you load the driver as

       follows:

       follows::





           modprobe e1000 InterruptThrottleRate=3000,3000,3000

           modprobe e1000 InterruptThrottleRate=3000,3000,3000
@@ -167,8 +167,8 @@ NOTE: When e1000 is loaded with default settings and multiple adapters 




RxDescriptors

RxDescriptors

-------------

-------------

Valid Range:   80-256 for 82542 and 82543-based adapters

Valid Range:   48-256 for 82542 and 82543-based adapters

               80-4096 for all other supported adapters

               48-4096 for all other supported adapters

Default Value: 256

Default Value: 256





This value specifies the number of receive buffer descriptors allocated

This value specifies the number of receive buffer descriptors allocated
@@ -230,8 +230,8 @@ speed. Duplex should also be set when Speed is set to either 10 or 100. 




TxDescriptors

TxDescriptors

-------------

-------------

Valid Range:   80-256 for 82542 and 82543-based adapters

Valid Range:   48-256 for 82542 and 82543-based adapters

               80-4096 for all other supported adapters

               48-4096 for all other supported adapters

Default Value: 256

Default Value: 256





This value is the number of transmit descriptors allocated by the driver.

This value is the number of transmit descriptors allocated by the driver.
@@ -242,41 +242,10 @@ NOTE: Depending on the available system resources, the request for a 
       higher number of transmit descriptors may be denied.  In this case,

       higher number of transmit descriptors may be denied.  In this case,

       use a lower number.

       use a lower number.





TxDescriptorStep

----------------

Valid Range:    1 (use every Tx Descriptor)

                4 (use every 4th Tx Descriptor)



Default Value:  1 (use every Tx Descriptor)



On certain non-Intel architectures, it has been observed that intense TX

traffic bursts of short packets may result in an improper descriptor

writeback. If this occurs, the driver will report a "TX Timeout" and reset

the adapter, after which the transmit flow will restart, though data may

have stalled for as much as 10 seconds before it resumes.



The improper writeback does not occur on the first descriptor in a system

memory cache-line, which is typically 32 bytes, or 4 descriptors long.



Setting TxDescriptorStep to a value of 4 will ensure that all TX descriptors

are aligned to the start of a system memory cache line, and so this problem

will not occur.



NOTES: Setting TxDescriptorStep to 4 effectively reduces the number of

       TxDescriptors available for transmits to 1/4 of the normal allocation.

       This has a possible negative performance impact, which may be

       compensated for by allocating more descriptors using the TxDescriptors

       module parameter.



       There are other conditions which may result in "TX Timeout", which will

       not be resolved by the use of the TxDescriptorStep parameter. As the

       issue addressed by this parameter has never been observed on Intel

       Architecture platforms, it should not be used on Intel platforms.



TxIntDelay

TxIntDelay

----------

----------

Valid Range:   0-65535 (0=off)

Valid Range:   0-65535 (0=off)

Default Value: 64

Default Value: 8





This value delays the generation of transmit interrupts in units of

This value delays the generation of transmit interrupts in units of

1.024 microseconds.  Transmit interrupt reduction can improve CPU

1.024 microseconds.  Transmit interrupt reduction can improve CPU
@@ -288,7 +257,7 @@ TxAbsIntDelay 
-------------

-------------

(This parameter is supported only on 82540, 82545 and later adapters.)

(This parameter is supported only on 82540, 82545 and later adapters.)

Valid Range:   0-65535 (0=off)

Valid Range:   0-65535 (0=off)

Default Value: 64

Default Value: 32





This value, in units of 1.024 microseconds, limits the delay in which a

This value, in units of 1.024 microseconds, limits the delay in which a

transmit interrupt is generated.  Useful only if TxIntDelay is non-zero,

transmit interrupt is generated.  Useful only if TxIntDelay is non-zero,
@@ -310,7 +279,7 @@ Copybreak 
---------

---------

Valid Range:   0-xxxxxxx (0=off)

Valid Range:   0-xxxxxxx (0=off)

Default Value: 256

Default Value: 256

Usage: insmod e1000.ko copybreak=128

Usage: modprobe e1000.ko copybreak=128





Driver copies all packets below or equaling this size to a fresh RX

Driver copies all packets below or equaling this size to a fresh RX

buffer before handing it up the stack.

buffer before handing it up the stack.
@@ -328,14 +297,6 @@ Default Value: 0 (disabled) 
Allows PHY to turn off in lower power states. The user can turn off

Allows PHY to turn off in lower power states. The user can turn off

this parameter in supported chipsets.

this parameter in supported chipsets.





KumeranLockLoss

---------------

Valid Range: 0-1

Default Value: 1 (enabled)



This workaround skips resetting the PHY at shutdown for the initial

silicon releases of ICH8 systems.



Speed and Duplex Configuration

Speed and Duplex Configuration

==============================

==============================
@@ -397,12 +358,12 @@ Additional Configurations 
  ------------

  ------------

  Jumbo Frames support is enabled by changing the MTU to a value larger than

  Jumbo Frames support is enabled by changing the MTU to a value larger than

  the default of 1500.  Use the ifconfig command to increase the MTU size.

  the default of 1500.  Use the ifconfig command to increase the MTU size.

  For example:

  For example::





       ifconfig eth<x> mtu 9000 up

       ifconfig eth<x> mtu 9000 up





  This setting is not saved across reboots.  It can be made permanent if

  This setting is not saved across reboots.  It can be made permanent if

  you add:

  you add::





       MTU=9000

       MTU=9000

Documentation/networking/index.rst

+1 −0
Original line number Original line Diff line number Diff line
@@ -11,6 +11,7 @@ Contents: 
   can

   can

   dpaa2/index

   dpaa2/index

   e100

   e100

   e1000

   kapi

   kapi

   z8530book

   z8530book

   msg_zerocopy

   msg_zerocopy

MAINTAINERS

+1 −1
Original line number Original line Diff line number Diff line
@@ -7090,7 +7090,7 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/net-queue.git 
T:	git git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/next-queue.git

T:	git git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/next-queue.git

S:	Supported

S:	Supported

F:	Documentation/networking/e100.rst

F:	Documentation/networking/e100.rst

F:	Documentation/networking/e1000.txt

F:	Documentation/networking/e1000.rst

F:	Documentation/networking/e1000e.txt

F:	Documentation/networking/e1000e.txt

F:	Documentation/networking/igb.txt

F:	Documentation/networking/igb.txt

F:	Documentation/networking/igbvf.txt

F:	Documentation/networking/igbvf.txt

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