freebsd-nq/sys/powerpc/conf/NOTES
Marcel Moolenaar de2fa7b8af Redefine bus_space_tag_t on PowerPC from a 32-bit integral to
a pointer to struct bus_space. The structure contains function
pointers that do the actual bus space access.

The reason for this change is that previously all bus space
accesses were little endian (i.e. had an explicit byte-swap
for multi-byte accesses), because all busses on Macs are little
endian.
The upcoming support for Book E, and in particular the E500
core, requires support for big-endian busses because all
embedded peripherals are in the native byte-order.

With this change, there's no distinction between I/O port
space and memory mapped I/O. PowerPC doesn't have I/O port
space. Busses assign tags based on the byte-order only.
For that purpose, two global structures exist (bs_be_tag and
bs_le_tag), of which the address can be taken to get a valid
tag.

Obtained from: Juniper, Semihalf
2007-12-19 18:00:50 +00:00

67 lines
1.3 KiB
Plaintext
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

# $FreeBSD$
#
# This file contains machine dependent kernel configuration notes. For
# machine independent notes, look in /sys/conf/NOTES.
#####################################################################
# CPU OPTIONS
#
# You must specify at least one CPU (the one you intend to run on).
cpu AIM
options POWERMAC #NewWorld Apple PowerMacs
options PSIM #GDB PSIM ppc simulator
options SC_OFWFB # OFW frame buffer
# Standard busses
device pci
device ofwd # Open Firmware disks
#####################################################################
# Devices we don't want to deal with
nodevice fdc
nodevice ppc
nodevice splash
# when splash works enable *_saver
nodevice blank_saver
nodevice daemon_saver
nodevice dragon_saver
nodevice fade_saver
nodevice fire_saver
nodevice green_saver
nodevice logo_saver
nodevice rain_saver
nodevice snake_saver
nodevice star_saver
nodevice warp_saver
nodevice daemon_saver
nodevice star_saver
nodevice snake_saver
# isa
nodevice pcii
nodevice tnt4882
# sound
nodevice snd_cmi
# wants gdb_cur
nodevice dcons
nodevice dcons_crom
#####################################################################
# Options we don't want to deal with
nooption SMP
nooption ADAPTIVE_SX
nooption GDB
nooption PPC_DEBUG
nooption PPC_PROBE_CHIPSET
nooption SC_NO_MODE_CHANGE
nooption UKBD_DFLT_KEYMAP