Message Handling Unit in NonSecure (r_mhu_ns)

Functions
fsp_err_t	R_MHU_NS_Open (mhu_ctrl_t *const p_ctrl, mhu_cfg_t const *const p_cfg)
fsp_err_t	R_MHU_NS_MsgSend (mhu_ctrl_t *const p_ctrl, uint32_t const msg)
fsp_err_t	R_MHU_NS_Close (mhu_ctrl_t *const p_ctrl)
fsp_err_t	R_MHU_NS_CallbackSet (mhu_ctrl_t *const p_api_ctrl, void(*p_callback)(mhu_callback_args_t *), void *const p_context, mhu_callback_args_t *const p_callback_memory)
void	R_MHU_NS_IsrSub (uint32_t irq)

Detailed Description

Driver for the MHU peripherals on RZ MPUs. This module implements the MHU Interface (for secure and non secure channels).

Overview

MHU is a function for message communication between Cortex-A55 and Cortex-M33 cores incorporated in RZ/G2L. Message communication is done by shared RAM (On-chip RAM) for passing message and response between CPUs and the function (MHU) for notifying when messages and responses are stored in the memory.

Features

The MHU_NS module supports the following features:

• Generate interrupt to notify Cortex-A55 when the message/response is stored in shared RAM(On-chip RAM).
• Receive interrupt when the message/response is stored by Cortex-A55 in shared RAM(On-chip RAM).

MHU_NS Basic Example

This is a basic example of minimal use of the MHU_NS in an application.

static uint32_t g_val;

void mhu_ns_basic_example (void)
{
    fsp_err_t err;
    uint32_t  msg = 0x0;

    /* Initializes the module. */
    err = R_MHU_NS_Open(&g_mhu_ns0_ctrl, &g_mhu_ns0_cfg);

    /* Handle any errors. This function should be defined by the user. */
    assert(FSP_SUCCESS == err);

    /* Set the user callback. */
    err = R_MHU_NS_CallbackSet(&g_mhu_ns0_ctrl, mhu_ns_example_callback, NULL, NULL);
    assert(FSP_SUCCESS == err);

    /* Send the data. */
    err = R_MHU_NS_MsgSend(&g_mhu_ns0_ctrl, msg);
    assert(FSP_SUCCESS == err);

    /* De-initializes the module. */
    err = R_MHU_NS_Close(&g_mhu_ns0_ctrl);
    assert(FSP_SUCCESS == err);
}

void mhu_ns_example_callback (mhu_callback_args_t * p_args)
{
    g_val = p_args->msg;
}

Classes
struct	st_mhu_ns_instance_ctrl
struct	st_mhu_ns_extended_cfg

Typedefs
typedef struct st_mhu_ns_instance_ctrl	mhu_ns_instance_ctrl_t
typedef struct st_mhu_ns_extended_cfg	mhu_ns_extended_cfg_t

---

Class Documentation

RZG::st_mhu_ns_instance_ctrl

struct RZG::st_mhu_ns_instance_ctrl

Channel control block. DO NOT INITIALIZE. Initialization occurs when mhu_api_t::open is called.

Public Attributes
uint32_t	open
	Indicates whether the open() API has been successfully called.
mhu_cfg_t const *	p_cfg
	Pointer to instance configuration.
R_MHU0_Type *	p_regs
	Base register for this channel.
uint32_t	channel
	channel
mhu_send_type_t	send_type
	Send Type: Message or Response.
uint32_t *	p_shared_memory_tx
	Pointer to send data area.
uint32_t *	p_shared_memory_rx
	Pointer to recv data area.
void(*	p_callback )(mhu_callback_args_t *)
	Pointer to callback and optional working memory.
mhu_callback_args_t *	p_callback_memory
	Pointer to non-secure memory that can be used to pass arguments to a callback in non-secure memory.
void *	p_context
	Pointer to context to be passed into callback function.

RZG::st_mhu_ns_extended_cfg

struct RZG::st_mhu_ns_extended_cfg

R_MHU_NS extended configuration

Class Members
void *	p_reg	Register base address for specified channel.

Typedef Documentation

mhu_ns_instance_ctrl_t

typedef struct st_mhu_ns_instance_ctrl mhu_ns_instance_ctrl_t

Channel control block. DO NOT INITIALIZE. Initialization occurs when mhu_api_t::open is called. Please refer to the struct st_mhu_ns_instance_ctrl.

mhu_ns_extended_cfg_t

typedef struct st_mhu_ns_extended_cfg mhu_ns_extended_cfg_t

R_MHU_NS extended configuration. Please refer to the struct st_mhu_ns_extended_cfg.

Function Documentation

R_MHU_NS_Open()

fsp_err_t R_MHU_NS_Open	(	mhu_ctrl_t *const	p_ctrl,
		mhu_cfg_t const *const	p_cfg
	)

Initializes the MHU_NS module instance. Implements mhu_api_t::open.

Return values

FSP_SUCCESS	Initialization was successful.
FSP_ERR_ASSERTION	A required input pointer is NULL.
FSP_ERR_ALREADY_OPEN	R_MHU_NS_Open has already been called for this p_ctrl.
FSP_ERR_INVALID_ARGUMENT	The specified IRQ number is invalid.
FSP_ERR_INVALID_CHANNEL	Requested channel number is not available on MHU_NS.

R_MHU_NS_MsgSend()

fsp_err_t R_MHU_NS_MsgSend	(	mhu_ctrl_t *const	p_ctrl,
		uint32_t const	msg
	)

Send message via MHU. Implements mhu_api_t::msgSend.

Return values

FSP_SUCCESS	Send message successfully.
FSP_ERR_ASSERTION	A required pointer was NULL.
FSP_ERR_NOT_OPEN	The instance control structure is not opened.

R_MHU_NS_Close()

fsp_err_t R_MHU_NS_Close

(

mhu_ctrl_t *const

p_ctrl

)

Disables interrupts, clears internal driver data. mhu_api_t::close.

Return values

FSP_SUCCESS	MHU_NS closed.
FSP_ERR_ASSERTION	p_ctrl is NULL.
FSP_ERR_NOT_OPEN	The instance control structure is not opened.

R_MHU_NS_CallbackSet()

fsp_err_t R_MHU_NS_CallbackSet	(	mhu_ctrl_t *const	p_api_ctrl,
		void(*)(mhu_callback_args_t *)	p_callback,
		void *const	p_context,
		mhu_callback_args_t *const	p_callback_memory
	)

Updates the user callback with the option to provide memory for the callback argument structure. Implements mhu_api_t::callbackSet.

Return values

FSP_SUCCESS	Callback updated successfully.
FSP_ERR_ASSERTION	A required pointer is NULL.
FSP_ERR_NOT_OPEN	The control block has not been opened.
FSP_ERR_NO_CALLBACK_MEMORY	p_callback is non-secure and p_callback_memory is either secure or NULL.

R_MHU_NS_IsrSub()

void RZG::R_MHU_NS_IsrSub

(

uint32_t

irq

)

MHU_NS receive interrupt sub function (for OpenAMP)

Parameters

[in]

irq

irq number for inter-core interrupt