描述
Cleanup request
Our new build server (https://custom.ardupilot.org) allows users to make their own firmwares by selecting and de-selecting features.
Sometimes the amount of code required to run a feature exceeds the flash space available on boards.
The more things we allow users to remove from the compilation the more likely they are to get a firmware that does everything they want.
A good example of this is scripting - users of 1MB boards would love to have it, but it is a large chunk of code and excluded from the 1MB builds by default.
note - each of these libraries can and should be done as a separate Pull Request!
There are many places in the code that we could allow users to exclude chunks of code on a piece-by-piece basis, for example:
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rangefinder library
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visual odometry backends
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AC_Avoid
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DONE AP_Winch backends
-
DONE GPS backends (@Hwurzburg is currently looking at these)
-
DONE rangefinder backends
-
DONE precision landing library
-
DONE compass backends
-
DONE airspeed backends
-
DONE AP_Mount backends
-
DONE battery monitor backends
-
DONE AP_Winch
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DONE AP_MSP backends
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DONE optical flow library
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DONE optical flow backends
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DONE RCInput backends (e.g. srxl)
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DONE FRSky library
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DONE FRSky backends
The larger the amount of code excised the more useful the change is. nm can be used to show the largest symbols in the compiled code:
pbarker@bluebottle:~/rc/ardupilot(pr/sitl-on-hw)$ arm-none-eabi-nm --demangle --size-sort --print-size build/NucleoH743/bin/ardurover | tail -20
3000de30 00001200 B NavEKF_core_common::nextP
080e58ac 00001264 T NavEKF3_core::FuseDragForces()
3000a484 000013c8 b xsimstate
080e4454 0000144c T NavEKF3_core::FuseSideslip()
080880c8 00001540 T SoloGimbalEKF::predictCovariance()
0810a8cc 0000163c T NavEKF2_core::FuseSideslip()
300183d0 00001658 b supported_frames
30011e20 000017e4 b icm40609
3001be50 000018a0 B SDU1
08111918 00001e78 t __static_initialization_and_destruction_0(int, int)
0810d548 00001f5c T NavEKF2_core::FuseOptFlow()
081330b0 00002014 T AP_Param::param_defaults_data
080e80fc 000022f8 T NavEKF3_core::FuseOptFlow(NavEKF3_core::of_elements const&, bool)
080d4e08 00002814 T NavEKF2_core::FuseMagnetometer()
0805ff8c 000029ee T NavEKF3_core::FuseBodyVel()
081460a4 00002ddb t ap_romfs_0
0805597c 00002edc T NavEKF3_core::FuseMagnetometer()
080df5ac 00004d0c T NavEKF2_core::CovariancePrediction()
0806626c 00005e70 T NavEKF3_core::CovariancePrediction(Vector3<double>*)
30002518 00006740 B rover
pbarker@bluebottle:~/rc/ardupilot(pr/sitl-on-hw)$
There are also some large wins available by filling out AP_NavEKF3_features.h with more options. This work will be much more complicated, but the ability to, for example, exclude magnetometers from the EKF's calculations would save a very large amount of code. (see https://github.com/ArduPilot/ardupilot/issues/19070 however)
The pattern we use is AP_<foo>_ENABLED. An example of this is AP_QUADPLANE_ENABLED. Typically the main library header will contain:
#ifndef AP_GPS_NOVA_ENABLED
#define AP_GPS_NOVA_ENABLED 1
#endif
The new option should also be added to the custom build server configuration: https://github.com/ArduPilot/ardupilot/blob/master/Tools/scripts/build_options.py
The code must be tested for compilation and working-ness with and without the option set.
Platform [ X ] All [ ] AntennaTracker [ ] Copter [ ] Plane [ ] Rover [ ] Submarine