Bill Studenmund <skippy@macro.Stanford.EDU> wrote;

>> I think the real problem is that the current scc driver doesn't use a
>> silo like the MI driver does. Thus anything in the kernel at spltty (or
>> splimp) blocks tty char reception. For the MI driver, spltty & splimp only
>> block the processing of characters, not their reception.
>> 
>> > Better pdma would be nice, but so would output DMA...
>> 
>> I haven't forgotten that Jason and I want to fix up the alpha version of
>> the driver, which will probably fix the pmax one too. ;-)

Just FYI, current arch/mips/mips/trap.c provides a software interrupt
machinary to decouple ZS interrupts from tty processing which works
like other NetBSD MI ZS drivers.

Tohru Nishimura 
Nara Institute of Science and Technology