vpo in ECP

[Terry Lambert]

Paulo Roberto wrote:
> Sorry hackers, I have posted this to questions at freebsd, but got no
> answer...
> 
> I did set my mainboard BIOS to use ECP transfer mode (dma 3 & irq 7). I
> edited my kernel to:
> 
> device ppc0 at isa? flags 0x8 irq 7
> 
> (is there a way to declare the dma I want to use? config complains if I
> add dma xyz)
> and when I boot I get:

Not sure if it's actually meaningful for the driver, but the
config file syntax is:

	device ppc0 at isa? flags 0x8 irq 7 drq 3


> Jul  1 10:36:42 delta /kernel: ppc0: <Parallel port> at port
> 0x378-0x37f irq 7 flags 0x8 on isa0
> Jul  1 10:36:42 delta /kernel: ppc0: Generic chipset (ECP-only) in ECP
> mode
> Jul  1 10:36:42 delta /kernel: ppc0: FIFO with 16/16/16 bytes threshold
> Jul  1 10:36:42 delta /kernel: ppi0: <Parallel I/O> on ppbus0
> Jul  1 10:36:42 delta /kernel: imm0: NIBBLE mode unavailable!
> 
> and my zip-100 drive does not get recognized. Is it possible to use vpo
> in ECP mode?? EPP and compatible modes are just too damn slow.

"man ppc".  The answer is "it depends on your chipset"; clearly,
it's not had anyone write explicit support for it yet.  The manual
page goes into some good detail on how to fix this; specifically,
you should look at the "Adding support to a new chipset" section.

See also "man vpo"; it discusses how to force specific modes for
your given chipset.  Probably, you should add specific support for
your chipset instead, so that other people who end up with the
same chipset don't end up having to repeat your problems.

-- Terry