[U-Boot] [PATCH v2] NS16550: buffer reads

[Wolfgang Denk]

Dear Simon Glass,

In message <CAPnjgZ2Qf-Egdp9WCnoWVPJmjic5BPF0Db+z1oD=fdb3aoLNKw at mail.gmail.com> you wrote:
> 
> > Even worse, if your input contains any commands that prodce output,
> > mayeb even lots of output (say "md $addr 10000") then even your
> > increased buffer size is not going to help you.
> 
> It helps a little - provided there are no more than 250 characters
> more 'serial input' after the md command, all is well. But I think
> this example is a little contrived.

250 characters? That's 4, maybe 5 lines of text.  Not exactly much...

> I feel this is a painful restriction. I see no indication of this
> limitation anywhere on the command line, no error or warning, etc. It
> is common to want to paste in new bootargs, new network parameters,
> new environment variables. U-Boot has a command line which purports to
> support this, and with a fairly straightforward patch and in the
> majority of cases, it can.

Pasting commands is OK for occasional use.  If you use this more
frequently you're doing something wrong.

> Yes this is a minor point, but it does bite people, and usability is important.

Agreed.  But consistent behaviour has it's charme as well: it's the
principle of least surprise (POLS) - see
http://en.wikipedia.org/wiki/Principle_of_least_surprise

As mentioned before, I'd rather have a clear restriction that is
consistent on all systems, instead of some "works for me"
implementation on a few systems that will break under just slightly
modified usage modes.

Best regards,

Wolfgang Denk

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