[realtek] Flow control question

[Donald Becker]

On Fri, 27 Sep 2002, Kelvin Proctor wrote:

> I'll apologise in advance for what might be a newbie question.

No, this qualifies as an advanced question.

> I'm wanting to set a realtek 8139 card to ignore flow control packets (for a
> real time system). 

I believe that what you actually want is to not negotiate flow control.
Just ignoring the packets after negotiating flow control might lead to
problems.

Here is a command to advertise NO flow control
   mii-diag eth0 -A 0x1e1
Here is a command to re-advertise flow control
   mii-diag eth0 -A 0x5e1

> I've downloaded and compiled rtl8139-diag.  This has shown that Tx flow
> control is enabled.

> I assume that I need to rebuild rtl8139-diag and link it against libflash.c
> to enable writing to the Flash ROM to do this.

No, libflash isn't relevant here.  There are two persistent memories
 "EEPROM", the tiny serial configuration EEPROM that must always exist.
    This 64 word chip only has room for configuration information.
  "Flash" the large empty socket that could hold a network boot program.
    At 64KB, it's a thousand times larger.

> [root@devel rtl8139]# ./rtl8139-diag -af
> rtl8139-diag.c:v2.10 9/18/2002 Donald Becker (becker@scyld.com)
>  http://www.scyld.com/diag/index.html
> Index #1: Found a RealTek RTL8139 adapter at 0x6100.
...
>  0x060: 1100b00f 05e1782d 00014441 00000000 ...

1100 782d ... ... 05e1 4441

Your are advertising 05e1
     +flow control 10+100*HDX+FDX
Your link partner advertised 441:
     +flow control 10baseT-FDX only (!?)

> Realtek station address 00:30:4f:04:ae:da, chip type 'rtl8139B'.
>   Receiver configuration: Promiscuous
>      Rx FIFO threshold 2048 bytes, maximum burst 2048 bytes, 32KB ring
>   Transmitter enabled with normal settings, maximum burst 1024 bytes.
...
>   Flow control: Tx enabled  Rx disabled.
>   The chip configuration is 0x10 0x4d, MII full-duplex mode.

-- 
Donald Becker				becker@scyld.com
Scyld Computing Corporation		http://www.scyld.com
410 Severn Ave. Suite 210		Second Generation Beowulf Clusters
Annapolis MD 21403			410-990-9993