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Re: SCSI driver
> > I'm testing ncr.c of OpenBSD at NetBSD/bebox.
> Is this a different ncr.c from what is on netbsd-current, in
OpenBSD's ncr.c supports big-endian CPU.
OpenBSD/powerpc has configuration for ncr.
> > There are some problems. First, endian.
> I assume because the code originally came from an i386, correct?
Yes. And, it is a problem to work in different endian with CPU(big)
> > Second, the address of main memory which saw from PCI master.
> > PCI/ISA view +------------+ 0x00000000
> > | PCI/ISA |
> > | memory(2G)|
> > +------------+ 0x80000000
> > =====> | main |
> > | memory(2G)| script for 53C810.
> > +------------+
> Okay, I must confess to some ignorance here. I'm not sure in your
> diagram what is supposed to be happening with the memory, versus what
> is actually happening. Would you mind explaining it a bit more in
CPU puts SCRIPT on the main memory for 53C810. 53C810 runs SCRIPT
in the main memory. Therefore, SCRIPT must be little-endian.
And, address must be changed in SCRIPT, because memory map of PCI master
is different from memory map of CPU.
See MPC105 PCI Bridge/Memory Controller User's manual, 3.1 Address Maps.
Table 3-1 versus Figure 3-4.
I am sorry that I can't explain well.
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