Custome C module with portYIELD_FROM_ISR fails to link

[ajstarrNZ]

Hi all,

I have a custom board design that uses an ESP32-PICO-D4. On this board is a SC16IS752 dual SPI UART, accessed from MP via a custom C module. I have found that characters are dropped, particularly at higher baud rates, due to the time that MP GPIO interrupts require. So, I would like to have the UART received character interrupt served via a FreeRTOS task, Adding a test function that creates a task that blinks an LED while running in parallel with the MP task was not a problem, however when trying to add support for a GPIO interrupt to service the UART IRQ I found that portYIELD_FROM_ISR() was preventing the module from successfully linking, generating the following error message:

spisvc.c:(.iram1.0+0x21): undefined reference to traceISR_EXIT_TO_SCHEDULER'`

Here is the relevant part of the task that sets up the interrupt handler:

    gpio_isr_handler_add(GPIO_NUM_34, spi_uart_isr_handler, NULL);
    
    for (;;) {
       xSemaphoreTake(spi_svc_sem, portMAX_DELAY);
       gpio_set_level(GPIO_NUM_12, 1);
       spisvc_uart_rx_fifos();
       gpio_set_level(GPIO_NUM_12, 0);
    }

And here is the (barebones) handler itself:

void spi_uart_isr_handler(void *param)
{
    static BaseType_t xHigherPriorityTaskWoken = pdFALSE;
        
    xSemaphoreGiveFromISR(spi_svc_sem, &xHigherPriorityTaskWoken);
    if( xHigherPriorityTaskWoken) {
        portYIELD_FROM_ISR(); 
    }
}

If I comment out portYIELD_FROM_ISR() it compiles and links without a problem, I'm assuming I need to link to some library or include some header that defines traceISR_EXIT_TO_SCHEDULER?

I have previously used vTaskDelay() without problems, so it doesn't seem to be a FreeRTOS library issue.

Any help greatly appreciated!