Re: [PATCH] Powerpc 8xx CPM_UART delay in receive

From: Alan Cox
Date: Thu Aug 16 2012 - 10:25:56 EST


> The PowerPC CPM is working differently. It doesn't use a fifo but
> buffers. Buffers are handed to the microprocessor only when they are
> full or after a timeout period which is adjustable. In the driver, the

Which is different how - remembering we empty the FIFO on an IRQ

> buffers are configured with a size of 32 bytes. And the timeout is set
> to the size of the buffer. That is this timeout that I'm reducing to 1
> byte in my proposed patch. I can't see what it would break for high
> speed I/O.

How can a timeout be measured in "bytes". Can we have a bit more clarity
on how the hardware works and take it from there ?

Alan
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