With a little assistance, I now have the MMU enabled.  I can successfully
get into initrom.  however, once it starts using the newly setup L1 page
table, it never comes back.  This leads me to think that the new L1PT is
not correct.  But it seems to be initialized correctly as far as I can see.

Anyone have any ideas?  [I've created a arch/netwinder so you can look at
sources.]

[NeTTrom] Second level jump mode
    [FB B0=0x00000046][FB B1=0x02000046][FB B2=0x00000000][FB B3=0x00000000]
    [Kern loc=0x03C00000]
    [VGA_30=0x01][VGA_71=0x10][VGA_72=0x05]
    [VGA_B2=0xDB][VGA_B3=0x54]
[CMD=ide0=autotune nwconsole=serial netconfig_eth0=disk netconfig_eth1=dhcp 
eth1=192.168.7.72/24 R1=0.0.0.0:192.168.7.3:n ]
Assuming A.OUT kernel
Copying 0x0019A175 bytes from 0x03C00200 to 0x0000C000
Initrd: scan 0x0019A175 bytes @ 0x03C00000.
Kernel entry point 0x0000C020

Press '*' TWICE to enter debug......Booting kernel...
**
NetBSD/netwinder booting ...
initarm: Configuring system ...
physmemory: 16384 pages at 0x00000000 -> 0x03ffffff
Allocating page tables
freestart = 0x1b4000, free_pages = 15948 (0x3e4c)
IRQ stack: p0x001d4000 v0xf01d4000
ABT stack: p0x001d5000 v0xf01d5000
UND stack: p0x001d6000 v0xf01d6000
SVC stack: p0x001d7000 v0xf01d7000
Creating L1 page table at 0x1b4000
Mapping kernel
map_chunk: pa=0 va=f0000000 sz=c000 rem=c000 acc=1 flg=c
map_chunk: PPPPPPPPPPPP
map_chunk: pa=c000 va=f000c000 sz=175000 rem=175000 acc=0 flg=c
map_chunk: PPPPLLLLLLLLLLLLLLLLLLLLLLLP
map_chunk: pa=181000 va=f0181000 sz=8000 rem=8000 acc=1 flg=c
map_chunk: PPPPPPPP
map_chunk: pa=189000 va=f0189000 sz=2a898 rem=2b000 acc=1 flg=c
map_chunk: PPPPPPPLLPPPP
Constructing L2 page tables
map_chunk: pa=1d4000 va=f01d4000 sz=1000 rem=1000 acc=1 flg=c
map_chunk: P
map_chunk: pa=1d5000 va=f01d5000 sz=1000 rem=1000 acc=1 flg=c
map_chunk: P
map_chunk: pa=1d6000 va=f01d6000 sz=1000 rem=1000 acc=1 flg=c
map_chunk: P
map_chunk: pa=1d7000 va=f01d7000 sz=2000 rem=2000 acc=1 flg=c
map_chunk: PP
map_chunk: pa=1b4000 va=f01b4000 sz=4000 rem=4000 acc=1 flg=0
map_chunk: PPPP
42000000 -> 420fffff @ fd000000
50000000 -> 500fffff @ fd100000
7c000000 -> 7c0fffff @ fd200000
79000000 -> 790fffff @ fd300000
7a000000 -> 7affffff @ fe000000
7b000000 -> 7bffffff @ ff000000
80000000 -> 800fffff @ fd400000
freestart = 0x1da000, free_pages = 15910 (0x3e26)
switching to new L1 page table  @0x1b4000...
--
Matt Thomas               Internet:   matt@3am-software.com
3am Software Foundry      WWW URL:    http://www.3am-software.com/bio/matt/
Cupertino, CA             Disclaimer: I avow all knowledge of this message