Pixhawk/PX4FMUv2 startup without external mag fails

[philipoe]

Bug Report

Issue:

On Pixhawk with rev. 3 microprocessor (i.e. compiled via px4fmu-v3_default), current master firmware (63121b7) and stock startup script (rcS with airframe "standard plane" / Autostart ID 2100), bootup without an external magnetometer does not work because lsm303d fails. The system is a 64bit Ubuntu 16.10LTS. The exact log output for the configuration is:

HW arch: PX4FMU_V2
HW type: V2
HW version: 0x0009000B
HW revision: 0x00000000
FW git-hash: 63121b7
FW version: 1.7.3 0 (17236736)
OS: NuttX
OS version: Release 7.22.0 (118882559)
OS git-hash: efc3d9e92bd10623ab3025f012fd7d481e1a7267
Build datetime: Mar 12 2018 13:40:08
Build uri: localhost
Toolchain: GNU GCC, 7.2.1 20170904 (release) [ARM/embedded-7-branch revision 255204]
MFGUID: 393839343335511000380045
MCU: STM32F42x, rev. 3
UID: 380045:33355110:39383934

Steps to reproduce the problem:

• By default, l3gd20 will start but lsm303d will not start because it is not part of the px4fmu-v3_default config file. The console output is as simple as "lsm303d: Command not found".
• When just adding drivers/imu/lsm303d to cmake/configs/nuttx_px4fmu-v3_default.cmake, suddenly neither l3gd20 nor lsm303d start up anymore after a power cycle. Console output is:

INFO [mpu6000] accel cutoff set to 30.00 Hz
INFO [mpu6000] gyro cutoff set to 30.00 Hz
WARN [mpu6000] no device on bus #5 (SPI4)
WARN [mpu9250] probe failed! 104
WARN [mpu9250] no device on bus 3
WARN [mpu9250] probe failed! 255
WARN [mpu9250] no device on bus 4
ERROR [l3gd20] driver start failed
WARN [lsm303d] SPI init failed
ERROR [lsm303d] driver start failed

However, when doing a soft reboot (via nsh reboot command), both sensors start up correctly!

Questions:

I know that it is preferred to use an external mag, but why is lsm303d completely disabled in nuttx_px4fmu-v3_default.cmake ? And why does it not start after a power cycle (the pixhawks were supplied via either an external power supply or the USB port, but the issue remained the same) although it does start after nsh's reboot?

Notes:

This was tested on 3 different Pixhawks, all with revision 3 microprocessors and thus 2MB flash (on the PCB, these are just marked as "PX4FMU 2.4"). Same issue on all of them. However, on a fourth Pixhawk (which also has a rev. 3 microprocessor) this works every time (PCB mark is "PX4FMU 2.4.6", could be an mRo Pixhawk)! Is this a known problem of some hardware versions of Pixhawk?

@dagar @ASM3

[tops4u]

Check current Master (IMHO the above is not current Master), since there was a Fix for SPI Bus Reset, which fixes the LSM303D not found after a Soft Reboot (Warm Start): #8992

[philipoe]

The "above" (63121b7) is the current master as of right now, and the issue unfortunately persists.

[LorenzMeier]

@philipoe Another fix went into master from @dagar - could you re-test?

[philipoe]

Tested on 2 different Pixhawk units during ~10 hard-reboots, worked every time.

Thanks @dagar for the quick fix!