Inter-CPU IRQ on ICU (r_icu_inter_cpu_irq)

Functions
fsp_err_t	R_ICU_INTER_CPU_IRQ_Open (icu_inter_cpu_irq_ctrl_t *const p_ctrl, icu_inter_cpu_irq_cfg_t const *const p_cfg)
fsp_err_t	R_ICU_INTER_CPU_IRQ_Generate (icu_inter_cpu_irq_ctrl_t *const p_ctrl)
fsp_err_t	R_ICU_INTER_CPU_IRQ_CallbackSet (icu_inter_cpu_irq_ctrl_t *const p_ctrl, void(*p_callback)(icu_inter_cpu_irq_callback_args_t *), void const *const p_context, icu_inter_cpu_irq_callback_args_t *const p_callback_memory)
fsp_err_t	R_ICU_INTER_CPU_IRQ_Close (icu_inter_cpu_irq_ctrl_t *const p_ctrl)

Detailed Description

Driver for the ICU peripheral on RZ microprocessor. This module implements the Inter CPU IRQ Interface.

Overview

The Inter-CPU IRQ on ICU driver implements an interface for inter-CPU interrupt.

It is possible to generate not only the interrupt inter-CPUs but also the software interrupt to its own CPU.

Note

When using inter-CPUs interrupts, it is necessary to use this instance on each CPU side.

Features

• Supports configuring interrupts for inter-CPUs or software interrupt to its own CPU.
  • Generating interrupt.
• Supports configuring a user callback function, which will be invoked by the HAL module when an inter-CPUs interrupt is generated.

Configuration

Build Time Configurations for r_icu_inter_cpu_irq

The following build time configurations are defined in fsp_cfg/r_icu_inter_cpu_irq_cfg.h:

Configuration	Options	Default	Description
Parameter Checking	Default (BSP) Enabled Disabled	Default (BSP)	If selected code for parameter checking is included in the build.
Multiplex Interrupt	Enabled Disabled	Disabled	Enable multiplex interrupt for a single driver.

Configurations for System > Inter-CPU IRQ (r_icu_inter_cpu_irq)

This module can be added to the Stacks tab via New Stack > System > Inter-CPU IRQ (r_icu_inter_cpu_irq).

Configuration	Options	Default	Description
Name	Name must be a valid C symbol	g_icu_inter_cpu_irq0	Module name.
Channel	Value must be an integer greater than or equal to 0	0	Specify the hardware channel.
Software Interrupt Priority	MCU Specific Options		Select the Software interrupt priority.
Callback	Name must be a valid C symbol	NULL	A user callback function can be provided here. If this callback function is provided, it is called from the interrupt service routine (ISR) each time the IRQn triggers

Clock Configuration

The ICU peripheral module doesn't require any specific clock settings.

Pin Configuration

This module does not use I/O pins.

Usage Notes

Use case 1) Software interrupt Single core usage

Software interrupts can be generated to CPU0 itself using INTCPU.

• R_ICU_INTER_CPU_IRQ_Open() can be used to configure the software interrupt notification.
  • When using INTCPU0 to generate a software interrupt for CPU0 itself, it needs to set "Software Interrupt Priority".
• R_ICU_INTER_CPU_IRQ_Generate() can be used to generate notification of configured software interrupts.

Example of stack configuration

stack	config	CPU0
0	Name	g_icu_inter_cpu_irq0
	Channel	0
	Software Interrupt Priority	12
	Callback	cpu0_ic0_callback

Image of single core software interrupt operation

ICU INTER CPU IRQ Single core usage

Use case 2) Software interrupt Dual core usage (2 channels)

Software interrupts can be generated between CPU0 and CPU1 using INTCPU.

• R_ICU_INTER_CPU_IRQ_Open() can be used to configure the software interrupt notification.
  • When using INTCPU1 to generate a software interrupt from CPU0 to CPU1.
    • On the CPU0 side, the "Software Interrupt Priority" setting shall be set to "disabled".
    • On the CPU1 side, "Software Interrupt Priority" must be set to receive software interrupt notifications.
  • When using INTCPU2 to generate a software interrupt from CPU1 to CPU0.
    • On the CPU0 side, "Software Interrupt Priority" must be set to receive software interrupt notifications.
    • On the CPU1 side, the "Software Interrupt Priority" setting shall be set to "disabled".
• R_ICU_INTER_CPU_IRQ_Generate() can be used to generate notification of configured software interrupts.
  • When using inter-CPUs interrupts, CPU0 and CPU1 must be after executing R_ICU_INTER_CPU_IRQ_Open() each other.

If the parameter check is Enable and "Callback" is "NULL", the R_ICU_INTER_CPU_IRQ_Open() function returns FSP_ERR_ASSERTION, so set any callback function.

Example of stack configuration

stack	config	CPU0	CPU1
0	Name	g_icu_inter_cpu_irq0	g_icu_inter_cpu_irq0
	Channel	1	1
	Software Interrupt Priority	Disabled	12
	Callback	NULL	cpu1_ic1_callback
1	Name	g_icu_inter_cpu_irq1	g_icu_inter_cpu_irq1
	Channel	2	2
	Software Interrupt Priority	12	Disabled
	Callback	cpu0_ic2_callback	NULL

Image of dual core software interrupt operation

ICU INTER CPU IRQ Dual core usage 2channels

Use case 3) Software interrupt Dual core usage (1 channel)

Software interrupts can be generated between CPU0 and CPU1 using same INTCPU.

• R_ICU_INTER_CPU_IRQ_Open() can be used to configure the software interrupt notification.
  • When using INTCPU3 to generate a software interrupt between CPU0 and CPU1, "Software Interrupt Priority" must be set on both CPUs.
  • Before each CPU generates a software interrupt, it can use "R_BSP_IrqDisable" to disable interrupts to itself.
  • After each CPU generates a software interrupt, it can use "R_BSP_IrqEnable" to enable interrupts to itself.
• R_ICU_INTER_CPU_IRQ_Generate() can be used to generate notification of configured software interrupts.
  • When using inter-CPUs interrupts, CPU0 and CPU1 must be after executing R_ICU_INTER_CPU_IRQ_Open() each other.

Property setting example

stack	config	CPU0	CPU1
0	Name	g_icu_inter_cpu_irq0	g_icu_inter_cpu_irq0
	Channel	3	3
	Software Interrupt Priority	12	12
	Callback	cpu0_ic3_callback	cpu1_ic3_callback

Image of dual core software interrupt operation

ICU INTER CPU IRQ Dual core usage 1channel

Examples

Basic Example

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

volatile bool g_icu_inter_cpu_irq_notification_receive_flag = false;

void r_icu_inter_cpu_irq_basic_example (void)
{
    fsp_err_t err;

    /* Open the driver. */
    err = R_ICU_INTER_CPU_IRQ_Open(&g_icu_inter_cpu_irq_ctrl, &g_icu_inter_cpu_irq_cfg);
    handle_error(err);

    /* Generate INTCPU0. */
    err = R_ICU_INTER_CPU_IRQ_Generate(&g_icu_inter_cpu_irq_ctrl);
    handle_error(err);

    while (!g_icu_inter_cpu_irq_notification_receive_flag)
    {
        /* Wait until an interrupt notification is received */
    }
}

void example_callback (icu_inter_cpu_irq_callback_args_t * p_args)
{
    FSP_PARAMETER_NOT_USED(p_args);

    g_icu_inter_cpu_irq_notification_receive_flag = true;
}

Function Documentation

R_ICU_INTER_CPU_IRQ_Open()

fsp_err_t R_ICU_INTER_CPU_IRQ_Open	(	icu_inter_cpu_irq_ctrl_t *const	p_ctrl,
		icu_inter_cpu_irq_cfg_t const *const	p_cfg
	)

Opens the icu_inter_cpu_irq driver. Implements icu_inter_cpu_irq_api_t::open().

Return values

FSP_SUCCESS	opened successfully.
FSP_ERR_IP_CHANNEL_NOT_PRESENT	The channel requested in p_cfg is not available on the device selected in r_bsp_cfg.h.
FSP_ERR_ALREADY_OPEN	Module is already open.
FSP_ERR_ASSERTION	Parameter check failure due to one or more reasons below: p_ctrl or p_cfg is NULL. Callback parameter is NULL.

R_ICU_INTER_CPU_IRQ_Generate()

fsp_err_t R_ICU_INTER_CPU_IRQ_Generate

(

icu_inter_cpu_irq_ctrl_t *const

p_ctrl

)

Generate software interrupt. Implements icu_inter_cpu_irq_api_t::generate().

Return values

FSP_SUCCESS	Function executed without issue.
FSP_ERR_ASSERTION	p_ctrl or p_src is NULL.
FSP_ERR_NOT_OPEN	Device is not open.

R_ICU_INTER_CPU_IRQ_CallbackSet()

fsp_err_t R_ICU_INTER_CPU_IRQ_CallbackSet	(	icu_inter_cpu_irq_ctrl_t *const	p_ctrl,
		void(*)(icu_inter_cpu_irq_callback_args_t *)	p_callback,
		void const *const	p_context,
		icu_inter_cpu_irq_callback_args_t *const	p_callback_memory
	)

Updates the user callback with the option to provide memory for the callback argument structure. Implements icu_inter_cpu_irq_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.

R_ICU_INTER_CPU_IRQ_Close()

fsp_err_t R_ICU_INTER_CPU_IRQ_Close

(

icu_inter_cpu_irq_ctrl_t *const

p_ctrl

)

Closes the icu_inter_cpu_irq. Implements icu_inter_cpu_irq_api_t::close().

Return values

FSP_SUCCESS	Device closed successfully.
FSP_ERR_NOT_OPEN	Device not opened.
FSP_ERR_ASSERTION	p_ctrl is NULL.