Who specifies the layout of FreeRTOSDebugConfig?

Kernel
1

Two demo projects, CORTEX_MPU_LPC54018_MCUXpresso and Safer_Interrupts_M33F_NXP_LPC55S69_MCUXpresso, declare a FreeRTOSDebugConfig byte array, which can be used by debuggers to introspect the OS version and various offsets into the TCB struct. I’ve also found a few projects on github that include this array. This structure is used by at least NXP MCUXpresso and SEGGER’s FreeRTOS plugin to improve TCB introspection.

I’ve run into a couple of problems with this array on FreeRTOS-MPU ports:

  1. Many of these offsets are > 256 bytes, so they can’t be represented correctly by FreeRTOSDebugConfig’s one-byte fields.
  2. A few additional fields are needed to properly handle FreeRTOS-MPU’s separate system call stack behavior.

In my project, I’ve added fields to this array to contain a high byte for the truncated offsets and 16-bit values for some additional offsets, and built a custom SEGGER FreeRTOS plugin that knows how to interpret these new 16-bit offsets. I’d love to have the newly added fields incorporated into a 1.5 version of the layout, but I haven’t found any information on who is in charge of specifying or revving FreeRTOSDebugConfig. Who I should send this proposal to, anybody have any idea?

The layout is versioned with the preprocessor symbols FREERTOS_DEBUG_CONFIG_MAJOR_VERSION and FREERTOS_DEBUG_CONFIG_MINOR_VERSION, and I’ve found projects on github with layouts 1.1, 1.2, 1.3, and 1.4. The specification seems to be:

v1.1:

    FREERTOS_DEBUG_CONFIG_MAJOR_VERSION,
    FREERTOS_DEBUG_CONFIG_MINOR_VERSION,
    tskKERNEL_VERSION_MAJOR,
    tskKERNEL_VERSION_MINOR,
    tskKERNEL_VERSION_BUILD,
    FREERTOS_MEMORY_SCHEME,
    offsetof(struct tskTaskControlBlock, pxTopOfStack),
#if (tskKERNEL_VERSION_MAJOR > 8)
    offsetof(struct tskTaskControlBlock, xStateListItem),
#else
    offsetof(struct tskTaskControlBlock, xGenericListItem),
#endif
    offsetof(struct tskTaskControlBlock, xEventListItem),
    offsetof(struct tskTaskControlBlock, pxStack),
    offsetof(struct tskTaskControlBlock, pcTaskName),
    offsetof(struct tskTaskControlBlock, uxTCBNumber),
    offsetof(struct tskTaskControlBlock, uxTaskNumber),
    configMAX_TASK_NAME_LEN,
    configMAX_PRIORITIES,

v1.2 adds:

#if (tskKERNEL_VERSION_MAJOR >= 10) && (tskKERNEL_VERSION_MINOR >= 2)
    configENABLE_MPU,
    configENABLE_FPU,
    configENABLE_TRUSTZONE,
	  configRUN_FREERTOS_SECURE_ONLY,
#else
    0, 0, 0, 0,

and v1.3 removes the #if making these fields mandatory.

v1.4 adds:

    configNUMBER_OF_CORES,
#if (configNUMBER_OF_CORES > 1)
    (uint8_t)sizeof(struct tskTaskControlBlock),
    (uint8_t)offsetof(struct tskTaskControlBlock, xTaskRunState),
#else
    0, 0,

for v1.5, I would like to add:

    // high bytes of v1.4 offsets
#if (configNUMBER_OF_CORES > 1)
    [22] = (uint8_t)(TCB_SIZE >> 8),
    [23] = (uint8_t)(RUN_STATE_OFFSET >> 8),
#else
    [22] = 0,
    [23] = 0,
#endif
    [24] = (uint8_t)(STATE_LIST_ITEM_OFFSET >> 8),
    [25] = (uint8_t)(EVENT_LIST_ITEM_OFFSET >> 8),
    [26] = (uint8_t)(STACK_OFFSET >> 8),
    [27] = (uint8_t)(TASKNAME_OFFSET >> 8),
    [28] = (uint8_t)(TCB_NUMBER_OFFSET >> 8),
    [29] = (uint8_t)(TASK_NUMBER_OFFSET >> 8),
    // new v1.5 offsets
    [30] = (uint8_t)PRIO_OFFSET,
    [31] = (uint8_t)(PRIO_OFFSET >> 8),
    [32] = (uint8_t)SP_OFFSET,
    [33] = (uint8_t)(SP_OFFSET >> 8),
    [34] = (uint8_t)LR_OFFSET,
    [35] = (uint8_t)(LR_OFFSET >> 8),
2

The forum won’t let me include links in my posts since I’m a new user. I found examples of the various layout versions in freertos_tasks_c_additions.h files in the Github projects openweave/openweave-core (1.1), ErichStyger/mcuoneclipse (1.2), and cesanta/mongoose (1.4). Some official FreeRTOS demo projects have the 1.3 layout in them.

3

Assuming you are talking about this, it comes from NXP (that is why it is in the NXP_Code subdirectory). So you should reach out to NXP.

You should now be able to include links.

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