sd_softdevice_disable() not returning during transport shutdown in DFU Bootloader

RE: sd_softdevice_disable() not returning during transport shutdown in DFU Bootloader

Vidar Berg — Mon, 19 Nov 2018 12:49:27 GMT

Hi Visti, I assume you are using the clock driver? In that case it's important to note that the driver will attempt to release the LF clock source when the NRF_SDH_EVT_STATE_DISABLED event is raised by nrf_sdh_disable_request(), this is not possible to do when WDT is enabled. The program will therefore become stuck in the while (nrf_clock_lf_is_running()){} loop. You can call nrf_drv_clock_lfclk_request(NULL) after softdevice enable to keep the LF clock on.

RE: sd_softdevice_disable() not returning during transport shutdown in DFU Bootloader

abhipray — Fri, 16 Nov 2018 20:05:57 GMT

Just adding that the problem I was seeing with sd_softdevice_disable() is back again when I try to use multiple DFU transports and I've described it in a new post.

RE: sd_softdevice_disable() not returning during transport shutdown in DFU Bootloader

Visti Andresen — Fri, 16 Nov 2018 09:57:12 GMT

I have a very similar issue while not involving a DFU update...

nrf_sdh_disable_request() never returns and the system current draw stays around 2.4mA until the watchdog resets the nRF52.

* Power up reset
* Start SD and do some measurements
* Begin sleep mode (disables the SD)
* Wake on GPIOTE event
* Start SD and do some measurements
* Begin sleep mode (disables the SD) disabling the SD never returns.

nrfjprog --family nrf52 --snr xxxxxx --readregs
R0:   0x2000FEF7
R1:   0xE000E100
R2:   0x40000000
R3:   0x00010000
R4:   0x20003920
R5:   0x20003715
R6:   0x2000300D
R7:   0x20002DA4
R8:   0x20002DA0
R9:   0x20002D9C
R10: 0x20002DA8
R11: 0x00000000
R12: 0x00000001
SP:   0x2000FEF0
LR:   0x00028CD5
PC:   0x00028CEC
xPSR: 0x01000000
MSP: 0x2000FEF0
PSP: 0x00000000

nRF5_SDK_14.2.0_17b948a and s132_nrf52_5.1.0_softdevice.hex

I have inserted a LED flash before and after the call to nrf_sdh_disable_request()

  for (int i=0; i<1000000; i++){
    NRF_GPIO->PIN_CNF[11] = 3<<0;
    NRF_GPIO->OUTCLR = 1<<11;
  }
  for (int i=0; i<1000000; i++){
    NRF_GPIO->PIN_CNF[11] = 3<<0;
    NRF_GPIO->OUTSET = 1<<11;
  }
  
  nrf_sdh_disable_request();

  for (int i=0; i<2000000; i++){
    NRF_GPIO->PIN_CNF[11] = 3<<0;
    NRF_GPIO->OUTCLR = 1<<11;
  }
  for (int i=0; i<2000000; i++){
    NRF_GPIO->PIN_CNF[11] = 3<<0;
    NRF_GPIO->OUTSET = 1<<11;
  }

The first disable functions just fine, the one after the soft reset hangs.
After a watchdog reset I can repeat the procedure.

I'm probably going to work around the issue by using a GPIOTE+RTC based wake and resetting the nRF52 using the WD timer.
The WD timer seem to be slightly cheaper (on avg.) than using the RTC, but since it isn't possible to disable the WD using a software reset I'm probably going that way.

Regards Visti Andresen

RE: sd_softdevice_disable() not returning during transport shutdown in DFU Bootloader

abhipray — Fri, 09 Nov 2018 23:32:22 GMT

Thank you for the offer to help debug! I just discovered a few things that seem to have fixed it: First, because I moved the RTT buffer RAM section around, I couldn't get proper logging until I power-cycled the nrf52. Second, I reduced the RTT number of buffers. And the biggest discovery was perhaps that I was enabling mem_manager and compiling the associated files leading to ; I had done that because sdk_config.h in the example has it enabled.

RE: sd_softdevice_disable() not returning during transport shutdown in DFU Bootloader

Vidar Berg — Fri, 09 Nov 2018 14:11:44 GMT

Hi,

So the program does not return from sd_softdevice_disable()? I haven't experienced that before. Can you read out the Core registers while the code is "stuck"? You can do this with the --readregs command in nrfjprog. E.g., nrfjprog --readregs. I would be happy to try debugging it here as well if you are able to share your project.