Introduce ATA_CAM kernel option, turning ata(4) controller drivers into
cam(4) interface modules. When enabled, this options deprecates all ata(4)
peripheral drivers (ad, acd, ...) and interfaces and allows cam(4) drivers
(ada, cd, ...) and interfaces to be natively used instead.
As side effect of this, ata(4) mode setting code was completely rewritten
to make controller API more strict and permit above change. While doing
this, SATA revision was separated from PATA mode. It allows DMA-incapable
SATA devices to operate and makes hw.ata.atapi_dma tunable work again.
Also allow ata(4) controller drivers (except some specific or broken ones)
to handle larger data transfers. Previous constraint of 64K was artificial
and is not really required by PCI ATA BM specification or hardware.
Submitted by: nwitehorn (powerpc part)
Right now syscons(4) uses a cons25-style terminal emulator. The
disadvantages of that are:
- Little compatibility with embedded devices with serial interfaces.
- Bad bandwidth efficiency, mainly because of the lack of scrolling
regions.
- A very hard transition path to support for modern character sets like
UTF-8.
Our terminal emulation library, libteken, has been supporting
xterm-style terminal emulation for months, so flip the switch and make
everyone use an xterm-style console driver.
I still have to enable this on i386. Right now pc98 and i386 share the
same /etc/ttys file. I'm not going to switch pc98, because it uses its
own Kanji-capable cons25 emulator.
IMPORTANT: What to do if things go wrong (i.e. graphical artifacts):
- Run the application inside script(1), try to reduce the problem and
send me the log file.
- In the mean time, you can run `vidcontrol -T cons25' and `export
TERM=cons25' so you can run applications the same way you did before.
You can also build your kernel with `options TEKEN_CONS25' to make all
virtual terminals use the cons25 emulator by default.
Discussed on: current@
splitting in bce(4) instead of (ab)using ZERO_COPY_SOCKETS that was not
propagated into if_bce.c anyway. It is disabled by default.
Approved by: davidch
MFC after: 3 days
x86emu to this new module.
This changeset also brings a fix for bugs introduced with the initial
x86emu commit, which prevents the user from using some display mode or
cause instant reboots during mode switch.
Submitted by: paradox <ddkprog yahoo com>
TCP_SORECEIVE_STREAM for the time being.
Requested by: brooks
Once compiled in make it easily switchable for testers by using a tuneable
net.inet.tcp.soreceive_stream
and a corresponding read-only sysctl to report the current state.
Suggested by: rwatson
MFC after: 2 days
Unfortunately, the wrappers that are present in pts(4) don't have the
mechanics to allow pty(4) to be unloaded safely, so I'm forcing this kld
to return EBUSY. This also means we have to enable some extra code in
pts(4) unconditionally.
Proposed by: rwatson
(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator. Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...). This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.
Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack. Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory. Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.
Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy. Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address. When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.
This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.
Bump __FreeBSD_version and update UPDATING.
Portions submitted by: bz
Reviewed by: bz, zec
Discussed with: gnn, jamie, jeff, jhb, julian, sam
Suggested by: peter
Approved by: re (kensmith)
1. USB_VERBOSE is more consistent with USB_DEBUG,
2. sys/dev/usb/usb_device.c uses option USB_VERBOSE and
not USBVERBOSE.
POLA with the USBVERBOSE option as it's found in 7-STABLE
has been considered but found insignificant in the face
of the USB stack overhaul.
Approved by: re (kensmith)
net80211 wireless stack. This work is based on the March 2009 D3.0 draft
standard. This standard is expected to become final next year.
This includes two main net80211 modules, ieee80211_mesh.c
which deals with peer link management, link metric calculation,
routing table control and mesh configuration and ieee80211_hwmp.c
which deals with the actually routing process on the mesh network.
HWMP is the mandatory routing protocol on by the mesh standard, but
others, such as RA-OLSR, can be implemented.
Authentication and encryption are not implemented.
There are several scripts under tools/tools/net80211/scripts that can be
used to test different mesh network topologies and they also teach you
how to setup a mesh vap (for the impatient: ifconfig wlan0 create
wlandev ... wlanmode mesh).
A new build option is available: IEEE80211_SUPPORT_MESH and it's enabled
by default on GENERIC kernels for i386, amd64, sparc64 and pc98.
Drivers that support mesh networks right now are: ath, ral and mwl.
More information at: http://wiki.freebsd.org/WifiMesh
Please note that this work is experimental. Also, please note that
bridging a mesh vap with another network interface is not yet supported.
Many thanks to the FreeBSD Foundation for sponsoring this project and to
Sam Leffler for his support.
Also, I would like to thank Gateworks Corporation for sending me a
Cambria board which was used during the development of this project.
Reviewed by: sam
Approved by: re (kensmith)
Obtained from: projects/mesh11s
Actually, as it did receive few tuning, the support is disabled by
default, but it can opt-in with the option ADAPTIVE_LOCKMGRS.
Due to the nature of lockmgrs, adaptive spinning needs to be
selectively enabled for any interested lockmgr.
The support is bi-directional, or, in other ways, it will work in both
cases if the lock is held in read or write way. In particular, the
read path is passible of further tunning using the sysctls
debug.lockmgr.retries and debug.lockmgr.loops . Ideally, such sysctls
should be axed or compiled out before release.
Addictionally note that adaptive spinning doesn't cope well with
LK_SLEEPFAIL. The reason is that many (and probabilly all) consumers
of LK_SLEEPFAIL are mainly interested in knowing if the interlock was
dropped or not in order to reacquire it and re-test initial conditions.
This directly interacts with adaptive spinning because lockmgr needs
to drop the interlock while spinning in order to avoid a deadlock
(further details in the comments inside the patch).
Final note: finding someone willing to help on tuning this with
relevant workloads would be either very important and appreciated.
Tested by: jeff, pho
Requested by: many
Thanks to (no special order) Emmanuel Dreyfus (manu@netbsd.org), Larry
Baird (lab@gta.com), gnn, bz, and other FreeBSD devs, Julien Vanherzeele
(julien.vanherzeele@netasq.com, for years of bug reporting), the PFSense
team, and all people who used / tried the NAT-T patch for years and
reported bugs, patches, etc...
X-MFC: never
Reviewed by: bz
Approved by: gnn(mentor)
Obtained from: NETASQ
- Preallocate some memory for ACPI tasks early enough. We cannot use
malloc(9) any more because spin mutex may be held here. The reserved
memory can be tuned via debug.acpi.max_tasks tunable or ACPI_MAX_TASKS
in kernel configuration. The default is 32 tasks.
- Implement a custom taskqueue_fast to wrap the new memory allocation.
This implementation is not the fastest in the world but we are being
conservative here.
For a slightly thorough explaination, please refer to
[1] http://people.freebsd.org/~ariff/SOUND_4.TXT.html .
Summary of changes includes:
1 Volume Per-Channel (vpc). Provides private / standalone volume control
unique per-stream pcm channel without touching master volume / pcm.
Applications can directly use SNDCTL_DSP_[GET|SET][PLAY|REC]VOL, or for
backwards compatibility, SOUND_MIXER_PCM through the opened dsp device
instead of /dev/mixer. Special "bypass" mode is enabled through
/dev/mixer which will automatically detect if the adjustment is made
through /dev/mixer and forward its request to this private volume
controller. Changes to this volume object will not interfere with
other channels.
Requirements:
- SNDCTL_DSP_[GET|SET][PLAY|REC]_VOL are newer ioctls (OSSv4) which
require specific application modifications (preferred).
- No modifications required for using bypass mode, so applications
like mplayer or xmms should work out of the box.
Kernel hints:
- hint.pcm.%d.vpc (0 = disable vpc).
Kernel sysctls:
- hw.snd.vpc_mixer_bypass (default: 1). Enable or disable /dev/mixer
bypass mode.
- hw.snd.vpc_autoreset (default: 1). By default, closing/opening
/dev/dsp will reset the volume back to 0 db gain/attenuation.
Setting this to 0 will preserve its settings across device
closing/opening.
- hw.snd.vpc_reset (default: 0). Panic/reset button to reset all
volume settings back to 0 db.
- hw.snd.vpc_0db (default: 45). 0 db relative to linear mixer value.
2 High quality fixed-point Bandlimited SINC sampling rate converter,
based on Julius O'Smith's Digital Audio Resampling -
http://ccrma.stanford.edu/~jos/resample/. It includes a filter design
script written in awk (the clumsiest joke I've ever written)
- 100% 32bit fixed-point, 64bit accumulator.
- Possibly among the fastest (if not fastest) of its kind.
- Resampling quality is tunable, either runtime or during kernel
compilation (FEEDER_RATE_PRESETS).
- Quality can be further customized during kernel compilation by
defining FEEDER_RATE_PRESETS in /etc/make.conf.
Kernel sysctls:
- hw.snd.feeder_rate_quality.
0 - Zero-order Hold (ZOH). Fastest, bad quality.
1 - Linear Interpolation (LINEAR). Slightly slower than ZOH,
better quality but still does not eliminate aliasing.
2 - (and above) - Sinc Interpolation(SINC). Best quality. SINC
quality always start from 2 and above.
Rough quality comparisons:
- http://people.freebsd.org/~ariff/z_comparison/
3 Bit-perfect mode. Bypasses all feeder/dsp effects. Pure sound will be
directly fed into the hardware.
4 Parametric (compile time) Software Equalizer (Bass/Treble mixer). Can
be customized by defining FEEDER_EQ_PRESETS in /etc/make.conf.
5 Transparent/Adaptive Virtual Channel. Now you don't have to disable
vchans in order to make digital format pass through. It also makes
vchans more dynamic by choosing a better format/rate among all the
concurrent streams, which means that dev.pcm.X.play.vchanformat/rate
becomes sort of optional.
6 Exclusive Stream, with special open() mode O_EXCL. This will "mute"
other concurrent vchan streams and only allow a single channel with
O_EXCL set to keep producing sound.
Other Changes:
* most feeder_* stuffs are compilable in userland. Let's not
speculate whether we should go all out for it (save that for
FreeBSD 16.0-RELEASE).
* kobj signature fixups, thanks to Andriy Gapon <avg@freebsd.org>
* pull out channel mixing logic out of vchan.c and create its own
feeder_mixer for world justice.
* various refactoring here and there, for good or bad.
* activation of few more OSSv4 ioctls() (see [1] above).
* opt_snd.h for possible compile time configuration:
(mostly for debugging purposes, don't try these at home)
SND_DEBUG
SND_DIAGNOSTIC
SND_FEEDER_MULTIFORMAT
SND_FEEDER_FULL_MULTIFORMAT
SND_FEEDER_RATE_HP
SND_PCM_64
SND_OLDSTEREO
Manual page updates are on the way.
Tested by: joel, Olivier SMEDTS <olivier at gid0 d org>, too many
unsung / unnamed heroes.
and used in a large number of files, but also because an increasing number
of incorrect uses of MAC calls were sneaking in due to copy-and-paste of
MAC-aware code without the associated opt_mac.h include.
Discussed with: pjd
with OpenBSD (and BSD/OS originally). We can't easly do it SOL_SOCKET option
as there is no more space for more SOL_SOCKET options, but this option also
fits better as an IP socket option, it seems.
- Implement this functionality also for IPv6 and RAW IP sockets.
- Always compile it in (don't use additional kernel options).
- Remove sysctl to turn this functionality on and off.
- Introduce new privilege - PRIV_NETINET_BINDANY, which allows to use this
functionality (currently only unjail root can use it).
Discussed with: julian, adrian, jhb, rwatson, kmacy
Introduce for this operation the reverse NO_ADAPTIVE_SX option.
The flag SX_ADAPTIVESPIN to be passed to sx_init_flags(9) gets suppressed
and the new flag, offering the reversed logic, SX_NOADAPTIVE is added.
Additively implements adaptive spininning for sx held in shared mode.
The spinning limit can be handled through sysctls in order to be tuned
while the code doesn't reach the release, after which time they should
be dropped probabilly.
This change has made been necessary by recent benchmarks where it does
improve concurrency of workloads in presence of high contention
(ie. ZFS).
KPI breakage is documented by __FreeBSD_version bumping, manpage and
UPDATING updates.
Requested by: jeff, kmacy
Reviewed by: jeff
Tested by: pho
includes support for NFSv4. The subsystem can optionally be linked
into the kernel using the two options:
NFSCL - the client
NFSD - the server
It is also built as three modules:
nfscl - the client
nfsd - the server
nfscommon - functions shared by the client and server
Approved by: kib (mentor)
Broadcom BCM43xx chipsets. This driver uses the v3 firmware that
needs to be fetched separately. A port will be committed to create
the bwi firmware module.
The driver matches the following chips: Broadcom BCM4301, BCM4307,
BCM4306, BCM4309, BCM4311, BCM4312, BCM4318, BCM4319
The driver works for 802.11b and 802.11g.
Limitations:
This doesn't support the 802.11a or 802.11n portion of radios.
Some BCM4306 and BCM4309 cards don't work with Channel 1, 2 or 3.
Documenation for this firmware is reverse engineered from
http://bcm.sipsolutions.net/
V4 of the firmware is needed for 11a or 11n support
http://bcm-v4.sipsolutions.net/
Firmware needs to be fetched from a third party, port to be committed
# I've tested this with a BCM4319 mini-pci and a BCM4318 CardBus card, and
# not connected it to the build until the firmware port is committed.
Obtained from: DragonFlyBSD, //depot/projects/vap
Reviewed by: sam@, thompsa@
as well as providing stateful load balancing when used with RADIX_MPATH.
- Currently compiled in to i386 and amd64 but disabled by default, it can be enabled at
runtime with 'sysctl net.inet.flowtable.enable=1'.
- Embedded users can remove it entirely from the kernel by adding 'nooption FLOWTABLE' to
their kernel config files.
- A minimal hookup will be added to ip_output in a subsequent commit. I would like to see
more review before bringing in changes that require more churn.
Supported by: Bitgravity Inc.
naming of the partitions (GEOM_PART_EBR_COMPAT). When
compatibility is enabled, changes to the partitioning are
disallowed.
Remove the device name aliasing added previously to provide
backward compatibility, but which in practice doesn't give
us anything.
Enable compatibility on amd64 and i386.
in FreeBSD 5.x to allow network device drivers to run with Giant
despite the network stack being Giant-free. This significantly
simplifies calls into ioctl() on network interfaces, especially
in the multicast code, as well as eliminates deferred invocation
of interface if_start routines.
Disable the build on device drivers still depending on
IFF_NEEDSGIANT as they no longer compile. They will be removed
in a few weeks if they haven't been made MPSAFE in that time.
Disabled drivers:
if_ar
if_axe
if_aue
if_cdce
if_cue
if_kue
if_ray
if_rue
if_rum
if_sr
if_udav
if_ural
if_zyd
Drivers that were already disabled because of tty changes:
if_ppp
if_sl
Discussed on: arch@
o add CFI_SUPPORT_STRATAFLASH compile option to enable support
o add new ioctls to get/set the factory and user/oem segments of the PR
and to get/set Protection Lock Register that fuses the user segment
o add #defines for bits in the status register
o update cfi_wait_ready to take an offset so it can be used to wait for
PR write completion and replace constants w/ symbolic names
Note: writing the user segment isn't correct; committing now to get review.
Sponsored by: Carlson Wireless
Reviewed by: imp, Chris Anderson
o remove HAL_CHANNEL; convert the hal to use net80211 channels; this
mostly involves mechanical changes to variable names and channel
attribute macros
o gut HAL_CHANNEL_PRIVATE as most of the contents are now redundant
with the net80211 channel available
o change api for ath_hal_init_channels: no more reglass id's, no more outdoor
indication (was a noop), anM contents
o add ath_hal_getchannels to have the hal construct a channel list without
altering runtime state; this is used to retrieve the calibration list for
the device in ath_getradiocaps
o add ath_hal_set_channels to take a channel list and regulatory data from
above and construct internal state to match (maps frequencies for 900MHz
cards, setup for CTL lookups, etc)
o compact the private channel table: we keep one private channel
per frequency instead of one per HAL_CHANNEL; this gives a big
space savings and potentially improves ani and calibration by
sharing state (to be seen; didn't see anything in testing); a new config
option AH_MAXCHAN controls the table size (default to 96 which
was chosen to be ~3x the largest expected size)
o shrink ani state and change to mirror private channel table (one entry per
frequency indexed by ic_devdata)
o move ani state flags to private channel state
o remove country codes; use net80211 definitions instead
o remove GSM regulatory support; it's no longer needed now that we
pass in channel lists from above
o consolidate ADHOC_NO_11A attribute with DISALLOW_ADHOC_11A
o simplify initial channel list construction based on the EEPROM contents;
we preserve country code support for now but may want to just fallback
to a WWR sku and dispatch the discovered country code up to user space
so the channel list can be constructed using the master regdomain tables
o defer to net80211 for max antenna gain
o eliminate sorting of internal channel table; now that we use ic_devdata
as an index, table lookups are O(1)
o remove internal copy of the country code; the public one is sufficient
o remove AH_SUPPORT_11D conditional compilation; we always support 11d
o remove ath_hal_ispublicsafetysku; not needed any more
o remove ath_hal_isgsmsku; no more GSM stuff
o move Conformance Test Limit (CTL) state from private channel to a lookup
using per-band pointers cached in the private state block
o remove regulatory class id support; was unused and belongs in net80211
o fix channel list construction to set IEEE80211_CHAN_NOADHOC,
IEEE80211_CHAN_NOHOSTAP, and IEEE80211_CHAN_4MSXMIT
o remove private channel flags CHANNEL_DFS and CHANNEL_4MS_LIMIT; these are
now set in the constructed net80211 channel
o store CHANNEL_NFCREQUIRED (Noise Floor Required) channel attribute in one
of the driver-private flag bits of the net80211 channel
o move 900MHz frequency mapping into the hal; the mapped frequency is stored
in the private channel and used throughout the hal (no more mapping in the
driver and/or net80211)
o remove ath_hal_mhz2ieee; it's no longer needed as net80211 does the
calculation and available in the net80211 channel
o change noise floor calibration logic to work with compacted private channel
table setup; this may require revisiting as we no longer can distinguish
channel attributes (e.g. 11b vs 11g vs turbo) but since the data is used
only to calculate status data we can live with it for now
o change ah_getChipPowerLimits internal method to operate on a single channel
instead of all channels in the private channel table
o add ath_hal_gethwchannel to map a net80211 channel to a h/w frequency
(always the same except for 900MHz channels)
o add HAL_EEBADREG and HAL_EEBADCC status codes to better identify regulatory
problems
o remove CTRY_DEBUG and CTRY_DEFAULT enum's; these come from net80211 now
o change ath_hal_getwirelessmodes to really return wireless modes supported
by the hardware (was previously applying regulatory constraints)
o return channel interference status with IEEE80211_CHANSTATE_CWINT (should
change to a callback so hal api's can take const pointers)
o remove some #define's no longer needed with the inclusion of
<net80211/_ieee80211.h>
Sponsored by: Carlson Wireless
The teken library already supports UTF-8 handling and xterm emulation,
but we have reasons to disable this right now. Because we should make it
easy and interesting for people to experiment with these features, allow
them to be set in kernel configuration files.
Before this commit we had a flag called `TEKEN_CONS25' to enable
cons25-style emulation. I'm calling it the opposite now, `TEKEN_XTERM',
because we want to enable it in kernel configuration files explicitly.
Requested by: kib
by the new kernel option COMPAT_ROUTE_FLAGS for binary backward
compatibility. The RTF_LLDATA flag maps to the same value as RTF_LLINFO.
RTF_LLDATA is used by the arp and ndp utilities. The RTF_LLDATA flag is
always returned to the userland regardless whether the COMPAT_ROUTE_FLAGS
is defined.
applications to specify a non-local IP address when bind()'ing a socket
to a local endpoint.
This allows applications to spoof the client IP address of connections
if (obviously!) they somehow are able to receive the traffic normally
destined to said clients.
This patch doesn't include any changes to ipfw or the bridging code to
redirect the client traffic through the PCB checks so TCP gets a shot
at it. The normal behaviour is that packets with a non-local destination
IP address are not handled locally. This can be dealth with some IPFW hackery;
modifications to IPFW to make this less hacky will occur in subsequent
commmits.
Thanks to Julian Elischer and others at Ironport. This work was approved
and donated before Cisco acquired them.
Obtained from: Julian Elischer and others
MFC after: 2 weeks
o add net80211 support for a tdma vap that is built on top of the
existing adhoc-demo support
o add tdma scheduling of frame transmission to the ath driver; it's
conceivable other devices might be capable of this too in which case
they can make use of the 802.11 protocol additions etc.
o add minor bits to user tools that need to know: ifconfig to setup and
configure, new statistics in athstats, and new debug mask bits
While the architecture can support >2 slots in a TDMA BSS the current
design is intended (and tested) for only 2 slots.
Sponsored by: Intel
o add support to byte swap EHCI descriptor contents; the IXP435
has dual-EHCI controllers integral but descriptor contents are
in big-endian format; this support is configured with the
USB_EHCI_BIG_ENDIAN_DESC option and enabled with EHCI_SCFLG_BIGEDESC
o clean up EHCI USBMODE register setup during init; add #defines for
bit values
o split debug support out into a new file and enable use through ddb
o while here remove a bunch of lingering netbsd-isms
Reviewed by: imp
container structures, depending on VIMAGE_GLOBALS compile time option.
Make VIMAGE_GLOBALS a new compile-time option, which by default will not
be defined, resulting in instatiations of global variables selected for
V_irtualization (enclosed in #ifdef VIMAGE_GLOBALS blocks) to be
effectively compiled out. Instantiate new global container structures
to hold V_irtualized variables: vnet_net_0, vnet_inet_0, vnet_inet6_0,
vnet_ipsec_0, vnet_netgraph_0, and vnet_gif_0.
Update the VSYM() macro so that depending on VIMAGE_GLOBALS the V_
macros resolve either to the original globals, or to fields inside
container structures, i.e. effectively
#ifdef VIMAGE_GLOBALS
#define V_rt_tables rt_tables
#else
#define V_rt_tables vnet_net_0._rt_tables
#endif
Update SYSCTL_V_*() macros to operate either on globals or on fields
inside container structs.
Extend the internal kldsym() lookups with the ability to resolve
selected fields inside the virtualization container structs. This
applies only to the fields which are explicitly registered for kldsym()
visibility via VNET_MOD_DECLARE() and vnet_mod_register(), currently
this is done only in sys/net/if.c.
Fix a few broken instances of MODULE_GLOBAL() macro use in SCTP code,
and modify the MODULE_GLOBAL() macro to resolve to V_ macros, which in
turn result in proper code being generated depending on VIMAGE_GLOBALS.
De-virtualize local static variables in sys/contrib/pf/net/pf_subr.c
which were prematurely V_irtualized by automated V_ prepending scripts
during earlier merging steps. PF virtualization will be done
separately, most probably after next PF import.
Convert a few variable initializations at instantiation to
initialization in init functions, most notably in ipfw. Also convert
TUNABLE_INT() initializers for V_ variables to TUNABLE_FETCH_INT() in
initializer functions.
Discussed at: devsummit Strassburg
Reviewed by: bz, julian
Approved by: julian (mentor)
Obtained from: //depot/projects/vimage-commit2/...
X-MFC after: never
Sponsored by: NLnet Foundation, The FreeBSD Foundation
module; the ath module now brings in the hal support. Kernel
config files are almost backwards compatible; supplying
device ath_hal
gives you the same chip support that the binary hal did but you
must also include
options AH_SUPPORT_AR5416
to enable the extended format descriptors used by 11n parts.
It is now possible to control the chip support included in a
build by specifying exactly which chips are to be supported
in the config file; consult ath_hal(4) for information.