Re: [RFC][PATCH] Xilinx uartlite serial driver

["David H. Lynch Jr." <dhlii@dlasys.net>]

Peter Korsgaard wrote:
>
>  Olof> 1. There's no early boot console support for PPC. There's another
>  Olof> uartlite patch that's floating around that has this, very useful for
>  Olof> early bringup tasks. I'd like to see this expanded to include that as
>  Olof> well (the regular part of the other driver seems more or less broken
>  Olof> though, so this is a better base driver). That shouldn't stop this part
>  Olof> of the driver to go in though, just possible future work.
>   
    There is more than one UartLite driver. I have one from someone else 
that includes DCR support.
    I wrote one that includes early boot console support - which is 
fairly trivial.
    I will try to separate out my early boot console patches - would 
this be the appropriate place to post them ?
   I beleive my driver is the one Peter  believes is broken.
> True. The board I have an uartlite on also has a 8250 so it hasn't
> been an issue for me so far - But it would indeed be a nice
> addition. Adding new stuff to arch/ppc at this moment isn't that
> sensible, so perhaps it makes most sense to wait til 4xx is supported
> under arch/powerpc?
>   
       I can't quite understand why one would build a Xilinx FPGA with both.

>
>  Olof> 3. It would be useful to demonstrate how to hook up the device all the
>  Olof> way through to the board port (i.e. add a config option and include it
>  Olof> in the ml403 platform code or similar). It's not hard, but it'd make it
>  Olof> easier for whomever comes next. Of course, with 4xx hopefully soon
>  Olof> moving over to arch/powerpc, this would be taken care of through the
>  Olof> device tree instead.
>
> Yes - Afaik none of the Xilinx boards comes with uartlites
> configured so it's not usable out-of-the-box, but you can ofcause do a
> setup with the proper #ifdefs like the 8250 stuff in virtex.c.
>   
    If Peter's driver is likely to get accepted I have all of the 
platform device code done for my own driver I can move it to his.
    I did a BSP for the Pico E12/E14, they use either UartLite out of 
the box, or a pseudo serial device they call the Keyhole
    that can be used if the E12/E14 are hosted (they are CF/Cardbus 
cards respectively)



-- 
Dave Lynch 					  	    DLA Systems
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Over 25 years' experience in platforms, languages, and technologies too numerous to list.

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