SCC used for WAN connection

SCC used for WAN connection

[Ruedi.Hofer]

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Hi,

I'd like to use one of the currently unused SCC's as WAN interface.
My ultimate dream is to run PPP or Frame Relay at a speed of 2Mb/s on it.

Is someone out there, who has
1. seen something like this?
2. written some kernel modules which support this functionality?
3. seen links containing related information?
4. ideas on how to do this?

If you were doin' something like that, would you first buy a WAN Interface
card for the PC? (eg. Sangoma, for tests?)
5. Has someone done tests with such a WAN card?

Thanx for any information,

Ruedi

Re: SCC used for WAN connection

[john zhan]

hi, Hugh McDonald

> On 30/5/00 Ruedi Hofer wrote,
> >
> >I'd like to use one of the currently unused SCC's as WAN interface.
> >My ultimate dream is to run PPP or Frame Relay at a speed of
> >2Mb/s on it.
me too.  in fact,   also, I need generic x.25 running on it.

>Hugh McDonald wrote,
> Hi Ruedi,
>     I too am hoping to one day run one SCC on an MBX860 board as a 2M WAN
> port. My general plan was to run the SCC in HDLC synchronous mode and use
> the PPP protocol on top of this.  From my quick investigation I found that
> in the LinuxPPc /kernel/drivers/char area there some files synclink.c
> (rewrite of serial.c) and n_hdlc.c (rewrite of ppp.c). Together they form a
> Linux Device Driver & line disipline for a synchrouous PPP link.
> Unfortunately the synclink.c driver is dedicated to a PCI serial card
> produced by MicroGate.

yes , we NEED a SCC HDLC mode synchronous  driver.



>    What is needed is a new version of 8xx_io/uart.c that sets up and drives
> the SCC as a synchronous serial port. This may then be useable with the sync
> PPP line disipline from the above driver.
>   I have started playing with it but only when I have some spare time....
 great!
I think it will probably  have big difference from the existing uart.c , and init routine must contain of  both uart and hdlc init code.
or ,  maybe need reconstruct the directory/file structures , add hdlc.c which supports full features of net device.



> and I dont seem to get much of that these days :-(
>    Please let me know if you get any info from other people or find out any
> other possible solutions....

I think we can  work together .
If you like,let's discuss it later , privately.

what do you say?


regards.
john zhan.
hacking time.


** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

RE: SCC used for WAN connection

[hugh.mcdonald]

On 30/5/00 Ruedi Hofer wrote,
>
>I'd like to use one of the currently unused SCC's as WAN interface.
>My ultimate dream is to run PPP or Frame Relay at a speed of
>2Mb/s on it.
>......

Hi Ruedi,
    I too am hoping to one day run one SCC on an MBX860 board as a 2M WAN
port. My general plan was to run the SCC in HDLC synchronous mode and use
the PPP protocol on top of this.  From my quick investigation I found that
in the LinuxPPc /kernel/drivers/char area there some files synclink.c
(rewrite of serial.c) and n_hdlc.c (rewrite of ppp.c). Together they form a
Linux Device Driver & line disipline for a synchrouous PPP link.
Unfortunately the synclink.c driver is dedicated to a PCI serial card
produced by MicroGate.
   What is needed is a new version of 8xx_io/uart.c that sets up and drives
the SCC as a synchronous serial port. This may then be useable with the sync
PPP line disipline from the above driver.
  I have started playing with it but only when I have some spare time....
and I dont seem to get much of that these days :-(

   Please let me know if you get any info from other people or find out any
other possible solutions....

Regards
   Hugh McDonald
   hugh.mcdonald@nokia.com

>-----Original Message-----
>From: EXT Ruedi.Hofer@ascom.ch [mailto:Ruedi.Hofer@ascom.ch]
>Sent: Tuesday, May 30, 2000 1:51 AM
>To: linuxppc-embedded@lists.linuxppc.org
>Cc: kernel@linux01.hasler.ascom.ch
>Subject: SCC used for WAN connection
>
>
>Hi,
>
>I'd like to use one of the currently unused SCC's as WAN interface.
>My ultimate dream is to run PPP or Frame Relay at a speed of
>2Mb/s on it.
>
>Is someone out there, who has
>1. seen something like this?
>2. written some kernel modules which support this functionality?
>3. seen links containing related information?
>4. ideas on how to do this?
>
>If you were doin' something like that, would you first buy a
>WAN Interface
>card for the PC? (eg. Sangoma, for tests?)
>5. Has someone done tests with such a WAN card?
>
>Thanx for any information,
>
>Ruedi
>

** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

Re: SCC used for WAN connection

[john zhan]

hi, Hugh McDonald

> On 30/5/00 Ruedi Hofer wrote,
> >
> >I'd like to use one of the currently unused SCC's as WAN interface.
> >My ultimate dream is to run PPP or Frame Relay at a speed of
> >2Mb/s on it.
me too.  in fact,   also, I need generic x.25 running on it.

>Hugh McDonald wrote,
> Hi Ruedi,
>     I too am hoping to one day run one SCC on an MBX860 board as a 2M WAN
> port. My general plan was to run the SCC in HDLC synchronous mode and use
> the PPP protocol on top of this.  From my quick investigation I found that
> in the LinuxPPc /kernel/drivers/char area there some files synclink.c
> (rewrite of serial.c) and n_hdlc.c (rewrite of ppp.c). Together they form a
> Linux Device Driver & line disipline for a synchrouous PPP link.
> Unfortunately the synclink.c driver is dedicated to a PCI serial card
> produced by MicroGate.
yes , we NEED a SCC HDLC mode synchronous  driver.

>    What is needed is a new version of 8xx_io/uart.c that sets up and drives
> the SCC as a synchronous serial port. This may then be useable with the sync
> PPP line disipline from the above driver.
>   I have started playing with it but only when I have some spare time....
great!
I think it will probably  have big difference from the existing uart.c , and init routine must contain of  both uart and hdlc init code.
or ,  maybe need reconstruct the directory/file structures , add hdlc.c which supports full features of net device.

> and I dont seem to get much of that these days :-(
>    Please let me know if you get any info from other people or find out any
> other possible solutions....
I think we can  work together .
If you like,let's discuss it later , privately.

what do you say?

regards.
john zhan.
hacking time.


** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

Re: SCC used for WAN connection

[Dan Malek]

john zhan wrote:

> me too.  in fact,   also, I need generic x.25 running on it.

So, write it.


>
> >    What is needed is a new version of 8xx_io/uart.c that sets up and drives

No, what you want is an SCC synchronous driver. Period.  Don't put
stuff like this in the uart driver, it is a big enough mess the
way it is.  I am close to having a really configurable uart driver,
so you can select what SCC/SMCs you want.  The uart driver is a uart
driver, not an SCC driver.

We will probably have to create some other functions for managing the
baud rate generators, but for synchronous I/O that clock should be
provided externally.

> > other possible solutions....
> I think we can  work together .
> If you like,let's discuss it later , privately.

I would strongly suggest not going off and making a big mess, then
sending me a patch and hope it gets applied to the kernel sources.

I have done lots of synchronous SCC, HDLC, and other things as custom
proprietary drivers for many customers.  Typically, the driver does
very little, just buffers the data for mmap()'ed applications that
do the real work.  I will see if I can provide some framework from
past work I have done, but some of these folks are quite protective
of this.

These drivers are not hard to write, and you can use examples from
Motorola's NetComm site to get started.  You may need to do some
uncached memory buffering tricks in Linux or just use cache management
functions to ensure cache coherency.

Don't use old silicon, like before Rev. C 860.  Most of these functions
don't work as advertised on SCC3 and SCC4, only on SCC1 and SCC2.  Make
sure you pay close attention to the external hardware, as clock and
data transition edges are criticaly to this working correctly.


	-- Dan

** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

RE: SCC used for WAN connection

[hugh.mcdonald]

Hi John & Dan,
   See Below for comments....

>Subject: Re: SCC used for WAN connection
>
>
>john zhan wrote:
>
>> me too.  in fact,   also, I need generic x.25 running on it.
>
>So, write it.
>
>
>>
>> >    What is needed is a new version of 8xx_io/uart.c that
>sets up and drives
>
>No, what you want is an SCC synchronous driver. Period.  Don't put
>stuff like this in the uart driver, it is a big enough mess the
>way it is.  I am close to having a really configurable uart driver,
>so you can select what SCC/SMCs you want.  The uart driver is a uart
>driver, not an SCC driver.

Sorry, my words were ambiguious, I did not actually intend to add to uart.c.
Dan is correct , sync does not belong in a uart driver.
I planned to write a new driver (based on uart.c skelaton). Also I was
planning to make it message/frame based not character based which also has
big impact on the design/functionality.

>
>We will probably have to create some other functions for managing the
>baud rate generators, but for synchronous I/O that clock should be
>provided externally.
>
>> > other possible solutions....
>> I think we can  work together .
>> If you like,let's discuss it later , privately.

john,
  I would like to further discuss with you.  I am on a training course for
the next few days so maybe sometime after that...
>
>I would strongly suggest not going off and making a big mess, then
>sending me a patch and hope it gets applied to the kernel sources.
>
  Agreed

>I have done lots of synchronous SCC, HDLC, and other things as custom
>proprietary drivers for many customers.  Typically, the driver does
>very little, just buffers the data for mmap()'ed applications that
>do the real work.  I will see if I can provide some framework from
>past work I have done, but some of these folks are quite protective
>of this.
>
Any code snippets would be more than welcome!

>These drivers are not hard to write, and you can use examples from
>Motorola's NetComm site to get started.  You may need to do some
>uncached memory buffering tricks in Linux or just use cache management
>functions to ensure cache coherency.
>
>Don't use old silicon, like before Rev. C 860.  Most of these functions
>don't work as advertised on SCC3 and SCC4, only on SCC1 and SCC2.  Make
>sure you pay close attention to the external hardware, as clock and
>data transition edges are criticaly to this working correctly.

Thanx for the info I shall check my hardware revs.

>
>	-- Dan
>

Cheers
    Hugh McD

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