Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
In the deep past, when this code compiled as a binary module, ath_hal
built as a module. This allowed custom, smaller HAL modules to be built.
This was especially beneficial for small embedded platforms where you
didn't require /everything/ just to run.
However, sometime around the HAL opening fanfare, the HAL landed here
as one big driver+HAL thing, and a lot of the (dirty) infrastructure
(ie, #ifdef AH_SUPPORT_XXX) to build specific subsets of the HAL went away.
This was retained in sys/conf/files as "ath_hal_XXX" but it wasn't
really floated up to the modules themselves.
I'm now in a position where for the reaaaaaly embedded boards (both the
really old and the last couple generation of QCA MIPS boards) having a
cut down HAL module and driver loaded at runtime is /actually/ beneficial.
This reduces the kernel size down by quite a bit. The MIPS modules look
like this:
adrian@gertrude:~/work/freebsd/head-embedded/src % ls -l ../root/mips_ap/boot/kernel.CARAMBOLA2/ath*ko
-r-xr-xr-x 1 adrian adrian 5076 May 23 23:45 ../root/mips_ap/boot/kernel.CARAMBOLA2/ath_dfs.ko
-r-xr-xr-x 1 adrian adrian 100588 May 23 23:45 ../root/mips_ap/boot/kernel.CARAMBOLA2/ath_hal.ko
-r-xr-xr-x 1 adrian adrian 627324 May 23 23:45 ../root/mips_ap/boot/kernel.CARAMBOLA2/ath_hal_ar9300.ko
-r-xr-xr-x 1 adrian adrian 314588 May 23 23:45 ../root/mips_ap/boot/kernel.CARAMBOLA2/ath_main.ko
-r-xr-xr-x 1 adrian adrian 23472 May 23 23:45 ../root/mips_ap/boot/kernel.CARAMBOLA2/ath_rate.ko
And the x86 versions, like this:
root@gertrude:/home/adrian # ls -l /boot/kernel/ath*ko
-r-xr-xr-x 1 root wheel 36632 May 24 18:32 /boot/kernel/ath_dfs.ko
-r-xr-xr-x 1 root wheel 134440 May 24 18:32 /boot/kernel/ath_hal.ko
-r-xr-xr-x 1 root wheel 82320 May 24 18:32 /boot/kernel/ath_hal_ar5210.ko
-r-xr-xr-x 1 root wheel 104976 May 24 18:32 /boot/kernel/ath_hal_ar5211.ko
-r-xr-xr-x 1 root wheel 236144 May 24 18:32 /boot/kernel/ath_hal_ar5212.ko
-r-xr-xr-x 1 root wheel 336104 May 24 18:32 /boot/kernel/ath_hal_ar5416.ko
-r-xr-xr-x 1 root wheel 598336 May 24 18:32 /boot/kernel/ath_hal_ar9300.ko
-r-xr-xr-x 1 root wheel 406144 May 24 18:32 /boot/kernel/ath_main.ko
-r-xr-xr-x 1 root wheel 55352 May 24 18:32 /boot/kernel/ath_rate.ko
.. so you can see, not building the whole HAL can save quite a bit.
For example, if you don't need AR9300 support, you can actually avoid
wasting half a megabyte of RAM. On embedded routers this is quite a
big deal.
The AR9300 HAL can be later further shrunk because, hilariously,
it indeed supports AH_SUPPORT_<xxx> for optionally adding chipset support.
(I'll chase that down later as it's quite a big savings if you're only
building for a single embedded target.)
So:
* Create a very hackish way to load/unload HAL modules
* Create module metadata for each HAL subtype - ah_osdep_arXXXX.c
* Create module metadata for ath_rate and ath_dfs (bluetooth is
currently just built as part of it)
* .. yes, this means we could actually build multiple rate control
modules and pick one at load time, but I'd rather just glue this
into net80211's rate control code. Oh well, baby steps.
* Main driver is now "ath_main"
* Create an "if_ath" module that does what the ye olde one did -
load PCI glue, main driver, HAL and all child modules.
In this way, if you have "if_ath_load=YES" in /boot/modules.conf
it will load everything the old way and stuff should still work.
* For module autoloading purposes, I actually /did/ fix up
the name of the modules in if_ath_pci and if_ath_ahb.
If you want to selectively load things (eg on ye cheape ARM/MIPS platforms
where RAM is at a premium) you should:
* load ath_hal
* load the chip modules in question
* load ath_rate, ath_dfs
* load ath_main
* load if_ath_pci and/or if_ath_ahb depending upon your particular
bus bind type - this is where probe/attach is done.
TODO:
* AR5312 module and associated pieces - yes, we have the SoC side support
now so the wifi support would be good to "round things out";
* Just nuke AH_SUPPORT_AR5416 for now and always bloat the packet
structures; this'll simplify other things.
* Should add a simple refcnt thing to the HAL RF/chip modules so you
can't unload them whilst you're using them.
* Manpage updates, UPDATING if appropriate, etc.
to this event, adding if_var.h to files that do need it. Also, include
all includes that now are included due to implicit pollution via if_var.h
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
DFS parameters fetched from the HAL.
Check whether the specific chipset supports RADAR reporting before
enabling DFS; or some of the (unset) DFS methods may fail.
Tested:
* AR5210 (correctly didn't enable radar PHY reporting)
* AR5212 (correctly enabled radar PHY reporting w/ the correct default
parameters.)
TODO:
* Now that I have this capability check in place, I could remove the
(empty) DFS methods from AR5210/AR5211.
* Test on AR5416, AR9160, AR9280.
PR: kern/170904
the assumption that ath_softc doesn't change size based on build time
configuration.
I picked up on this because suddenly radar stuff didn't work; and
although the ath_dfs code was setting sc_dodfs=1, the main ath driver
saw sc_dodfs=0.
So for now, include opt_ath.h in driver source files. This seems like
the sane thing to do anyway.
I'll have to do a pass over the code at some later stage and turn
the radiotap TX/RX structs into malloc'ed memory, rather than in-line
inside of ath_softc. I'd rather like to keep ath_softc the same
layout regardless of configuration parameters.
Pointy hat to: adrian
a buffer pointer.
For large radar pulses, the AR9130 and later will return a series of
FFT results for software processing. These can overflow a single 2KB
buffer on longer pulses. This would result in undefined buffer behaviour.
radar parameters for the AR5416 and later NICs.
These parameters have been tested on the following NICs:
* AR5416
* AR9160
* AR9220
* AR9280
And yes, these will return radar pulse parameters and (for AR9160 and later)
radar FFT information as PHY errors.
This is again not enough to do radar detection, it's just here to faciliate
development and validation of radar detection algorithms.
The (pulse, not FFT) decoding code for AR5212, AR5416 and later NICs exist
in the HAL.
This code is disabled for now as generating radar PHY errors can quickly
cause issues in busy environment.s Some further debugging of the RX path
is needed.
Finally, these parameters are likely not useful for the AR5212 era NICs.
The madwifi-dfs branch should have suitable example parameters for the
11a era NICs.
and the Atheros reference code.
The radar detection code needs to know what the current DFS domain is.
Since net80211 doesn't currently know this information, it's extracted
from the HAL regulatory domain information.
The specifics:
* add a new ath_dfs API hook, ath_dfs_init_radar_filters(), which
updates the radar filters whenever the regulatory domain changes.
* add HAL_DFS_DOMAIN which describes the currently configured DFS domain .
* add a new HAL internal variable which tracks the currently configured
HAL DFS domain.
* add a new HAL capability, HAL_CAP_DFS_DMN, which returns the currently
configured HAL DFS domain setting.
* update the HAL DFS domain setting whenever the channel setting is
updated.
Since this isn't currently used by any radar code, these should all
be no-ops for existing users.
Obtained from: Atheros
Submitted by: KBC Networks, sibridge
Approved by: re (kib, blanket)
Since no actual radar data is ever handled, this won't
do anything. It's mostly here as a reference for those who
wish to experiment with radar detection.
Approved by: re (kib)
This is in no way a complete DFS/radar detection implementation!
It merely creates an abstracted interface which allows for future
development of the DFS radar detection code.
Note: Net80211 already handles the bulk of the DFS machinery,
all we need to do here is figure out that a radar event has occured
and inform it as such. It then drives the DFS state engine for us.
The "null" DFS radar detection module is included by default;
it doesn't require a device line.
This commit:
* Adds a simple abstracted layer for radar detection state -
sys/dev/ath/ath_dfs/;
* Implements a null DFS module which doesn't do anything;
(ie, implements the exact behaviour at the moment);
* Adds hooks to the ath driver to process received radar events
and gives the DFS module a chance to determine whether
a radar has been detected.
Obtained from: Atheros
