File content as of revision 0:ccdea31d8eba:

#include <stm32f4xx_hal.h>
#include <apex_types.h>
#include <apex_queuing.h>

#include "context.h"
#include "drivers/time_get.h"
#include "process.h"
#include "part_scheduler.h"

#include "ports.h"


static uint32_t pop(uint32_t *p)
{
    const uint32_t ret = *(uint32_t *)(*p);
    *p += 4;
    return ret;
}


void SVC_Handler(void)
{
    ARM_HW_context_state* stack;

    __ASM volatile (
        "TST	LR, #0x4    	\n\t"		// Test bit 2 of EXC_RETURN
        "ITE	EQ      		\n\t"		// Which stack pointer was used?
        "MRSEQ  %0, MSP         \n\t"       // Move MSP into pointer if EQ flag is set
        "MRSNE  %0, PSP         \n\t"       // Move SSP into pointer if NE flag is set
        : "=r"  (stack)
        : :
    );

    /* Disable sysTick */
    SysTick->CTRL =
        SysTick_CTRL_CLKSOURCE_Msk |
        SysTick_CTRL_ENABLE_Msk;

    switch (stack->R0) {
    case 0xc0ffee0a:
    {
        uint8_t argc = 3;
        uint32_t argv[argc];

        while(argc--) {
            argv[argc] = pop(&stack->R2);
        }

        runtime_create_process(
            (PROCESS_ATTRIBUTE_TYPE *) argv[0],
            (PROCESS_ID_TYPE *) argv[1],
            (RETURN_CODE_TYPE *) argv[2]);
        break;
    }
    case 0xc0ffee0b:
    {
        uint64_t time = TIME_Get_Total();
        stack->R0 = NO_ERROR;
        stack->R1 = (uint32_t) time;
        stack->R2 = (uint32_t) (time >> 32);
        break;
    }
    case 0xc0ffee0c:
    {
        uint8_t argc = 7;
        uint32_t argv[argc];

        while(argc--) {
            argv[argc] = pop(&stack->R2);
        }

        create_queuing_port(
            (char *) argv[0],
            (MESSAGE_SIZE_TYPE) argv[1],
            (MESSAGE_RANGE_TYPE) argv[2],
            (PORT_DIRECTION_TYPE) argv[3],
            (QUEUING_DISCIPLINE_TYPE) argv[4],
            (QUEUING_PORT_ID_TYPE *) argv[5],
            (RETURN_CODE_TYPE *) argv[6]);
        break;
    }
    case 0xc0ffee0d:
    {
        uint8_t argc = 5;
        uint32_t argv[argc];

        while(argc--) {
            argv[argc] = pop(&stack->R2);
        }

        recieve_queuing_message(
            (QUEUING_PORT_ID_TYPE) argv[0],
            (SYSTEM_TIME_TYPE) argv[1],
            (MESSAGE_ADDR_TYPE) argv[2],
            (MESSAGE_SIZE_TYPE *) argv[3],
            (RETURN_CODE_TYPE *) argv[4]);
        break;
    }
    case 0xc0ffee0e:
    {
        uint8_t argc = 5;
        uint32_t argv[argc];

        while(argc--) {
            argv[argc] = pop(&stack->R2);
        }

        send_queuing_message(
            (QUEUING_PORT_ID_TYPE) argv[0],
            (MESSAGE_ADDR_TYPE) argv[1],
            (MESSAGE_SIZE_TYPE) argv[2],
            (SYSTEM_TIME_TYPE) argv[3],
            (RETURN_CODE_TYPE *) argv[4]);
        break;
    }
    case 0xc0ffee0f:
    {
        uint8_t argc = 3;
        uint32_t argv[argc];

        while(argc--) {
            argv[argc] = pop(&stack->R2);
        }

        get_queuing_port_id(
            (char *) argv[0],
            (QUEUING_PORT_ID_TYPE *) argv[1],
            (RETURN_CODE_TYPE *) argv[2]);
        break;
    }
    case 0xc0ffee10:
    {
        uint8_t argc = 3;
        uint32_t argv[argc];

        while(argc--) {
            argv[argc] = pop(&stack->R2);
        }

        get_queuing_port_status(
            (QUEUING_PORT_ID_TYPE) argv[0],
            (QUEUING_PORT_STATUS_TYPE *) argv[1],
            (RETURN_CODE_TYPE *) argv[2]);
        break;
    }
    case 0xc0ffee11:
    {
        process_stop_self();
        break;
    }
    default:
        break;
    }

    /* Enable sysTick */
    SysTick->CTRL =
        SysTick_CTRL_CLKSOURCE_Msk |
        SysTick_CTRL_TICKINT_Msk |
        SysTick_CTRL_ENABLE_Msk;
}