us_ticker_fire_interrupt: Event handler is never called

[fkjagodzinski]

Description

• Type: Bug
• Priority: Major

Bug

Target
NUCLEO_F070RB, EFM32GG_STK3700

Toolchain
GCC_ARM, ARM, IAR

Toolchain version
GCC_ARM v6.3.1,
ARM uvision v5.24.2.0,
IAR IAR ANSI C/C++ Compiler V7.80.4.12462/W32 for ARM

mbed-cli version
1.2.0

mbed-os sha
814eaa9

Code

#include "mbed.h"
#include "hal/ticker_api.h"
#include "rtos.h"

Semaphore sem(0,1);

void foo(uint32_t id) {
    (void) id;
    sem.release();
}

int main() {
    ticker_event_t e;
    const ticker_data_t *us_td = get_us_ticker_data();
    ticker_set_handler(us_td, foo);
    ticker_insert_event_us(us_td, &e, 0, NULL);

    // As ticker_insert_event_us() is called with a timestamp earlier
    // than the current  -- us_td->interface->fire_interrupt is called.

    // sem should have been released by us_ticker_fire_interrupt()
    int32_t num_tokens = sem.wait(0);

    DigitalOut led1(LED1, 1);
    while (true) {
        if (num_tokens) {
            led1 = !led1;
        }
        wait(0.1);
    }
}

Expected behavior
The ticker event handler foo() is called immediately after ticker_insert_event_us().

Actual behavior
The ticker event handler foo is never called.

cc @bulislaw @0xc0170

[bulislaw]

So this change is incorrect? https://github.com/ARMmbed/mbed-os/pull/5019/files

If not all targets conform we shouldn't change documentation. We could add a check in the function to actually not insert the event if it was in the past. We can fix it when we will come to rewriting HAL spec for that.

[fkjagodzinski]

I'd say that #5019 is correct because an event is inserted for every target I've tested.

This issue regards what happens just after the insertion. The event handler isn't called on NUCLEO_F070RB & EFM32GG_STK3700. Other boards like K64F, NUCLEO_L476RG and NUCLEO_F429ZI work as expected -- the handler is called immediately after insertion of the event.

[bulislaw]

But the original specification said it won't be called, so actually only these boards conform? Am I missing something?

[0xc0170]

ticker_insert_event_us(us_td, &e, 0, NULL); would be better to get current and use current - some margin (0 should work also though).

@fkjagodzinski Is this an issue with fire interrupt? I quickly checked EFM32, seems like we might have missed to set overflow counter to 0 if fire_interrupt is invoked.

@stevew817 @akselsm

@bcostm @adustm @LMESTM @jeromecoutant

[fkjagodzinski]

the original specification said it won't be called

@bulislaw Please take a look at /TESTS/mbed_hal/ticker/main.cpp.

[fkjagodzinski]

The issue seems to be resolved for NUCLEO_F070RB board by #5012.

For the EFM32GG_STK3700 however -- the bug is still present.

[0xc0170]

For the EFM32GG_STK3700 however -- the bug is still present.

bump @stevew817 @akselsm

[0xc0170]

As suspected overflow counter and flag needed to be set. Fixed here: #5176, please review