按键配置

#include "key_it.h"
#include "stm32mp1xx_gpio.h"
#include "stm32mp1xx_gic.h"
#include "stm32mp1xx_exti.h"
#include "stm32mp1xx_rcc.h"

void key_it_config()
{
	/* RCC使能GPIOF时钟 */
	RCC->MP_AHB4ENSETR |= (1<<5);
	/* 设置PF9 PF7 PF8输入 */
	GPIOF->MODER &= (~(0x3 << 14));
	GPIOF->MODER &= (~(0x3 << 16));
	GPIOF->MODER &= (~(0x3 << 18));
	
	/* 设置PF9 PF7 PF8产生EXTI事件 EXTI_EXTICRx */
	EXTI->EXTICR2 &= ~(0xff<<24);
	EXTI->EXTICR2 |= (0x05<<24);
	
	EXTI->EXTICR3 &= ~(0xff);
	EXTI->EXTICR3 |= (0x05);

	EXTI->EXTICR3 &= ~(0xff<<8);
	EXTI->EXTICR3 |= (0x05<<8);
	
	/* 设置事件触发方式为下降沿触发EXTI_FISR1 */
	EXTI->FTSR1 |= (1<<7);
	EXTI->FTSR1 |= (1<<8);
	EXTI->FTSR1 |= (1<<9);
	
	/* 设置EXTI事件触发不屏蔽XITI_IMR1 */
	EXTI->C1IMR1 |= (1<<7);
	EXTI->C1IMR1 |= (1<<8);
	EXTI->C1IMR1 |= (1<<9);


	/* 使能中断能转发到特定的CPU接口层GICD_ISENABLERx */
	GICD->ISENABLER[3] |= (1<<3);
	GICD->ISENABLER[3] |= (1<<2);
	GICD->ISENABLER[3] |= (1<<1);
	
	/* GICD_IPPIORITYRx设置中断优先级 */
	GICD->IPRIORITYR[24] &= ~(0x1f<<27);
	GICD->IPRIORITYR[24] &= ~(0x1f<<19);
	GICD->IPRIORITYR[24] &= ~(0x1f<<11);
	
	/* 设置当前终端被转发到哪一个CPU处理GIC_ITARGETSRx */
	GICD->ITARGETSR[24] &= ~(0x03<<24);
	GICD->ITARGETSR[24] |= (0x01<<24);
	GICD->ITARGETSR[24] &= ~(0x03<<16);
	GICD->ITARGETSR[24] |= (0x01<<16);
	GICD->ITARGETSR[24] &= ~(0x03<<8);
	GICD->ITARGETSR[24] |= (0x01<<8);

	/* 使能组0转发终端GICD_CTLR */
	GICD->CTRL |= 0x1;
	
	/* 设置中断优先级掩码GICC_PMR */
	GICC->PMR |= (0x1f<<3);
	
	/* 使能CPU可以处理组0转发的终端GICC_CTLR */
	GICC->CTRL |= 0x1;
	
}

中断实现

#include "stm32mp1xx_gic.h"
#include "stm32mp1xx_exti.h"
#include "beep.h"

#define EXTI9_IRQ 99
#define EXTI8_IRQ 98
#define EXTI7_IRQ 97

extern void printf(const char *fmt, ...);
unsigned int i = 0;
void do_irq(void) 
{
	/* 保存终端号 */
	int irqno;
	irqno = GICC->IAR & 0x3ff;

	if(irqno == EXTI9_IRQ)
	{
		delay(1000);
		if(irqno == EXTI9_IRQ)
		{
			/* KEY1中断处理 */
			printf("KEY1 pressed!\n\r");
			/* 蜂鸣器 */
			hal_gpio_write(GPIOB, 6, !hal_gpio_read(GPIOB, 6));
			/* 清除挂起中断标志位GICD_ICPENDRx */
			GICD->ICPENDR[3] |= (1<<3);	
			/* 清除终端触发标志EXTI_FRR1 */
			EXTI->FPR1 |= (1<<9);
		}
	}
	else if(irqno == EXTI8_IRQ)
	{
		delay(1000);
		if(irqno == EXTI8_IRQ)
		{
			/* KEY3中断处理 */
			printf("KEY3 pressed!\n\r");
			/* 风扇 */
			hal_gpio_write(GPIOE, 8, !hal_gpio_read(GPIOE, 8));
			/* 清除挂起中断标志位GICD_ICPENDRx */
			GICD->ICPENDR[3] |= (1<<2);
			/* 清除终端触发标志EXTI_FRR1 */
			EXTI->FPR1 |= (1<<8);
		}
	}
	else if(irqno == EXTI7_IRQ)
	{
		delay(1000);
		if(irqno == EXTI7_IRQ)
		{
			/* KEY2中断处理 */
			printf("KEY2 pressed!\n\r");
			/* LED灯 */
			hal_gpio_write(GPIOE, 9, !hal_gpio_read(GPIOE, 9));
			/* 清除挂起中断标志位GICD_ICPENDRx */
			GICD->ICPENDR[3] |= (1<<1);
			/* 清除终端触发标志EXTI_FRR1 */
			EXTI->FPR1 |= (1<<7);
		}
	}
	
	
	/* 清除处理完的中断号GICC_EOIR */
	GICC->EOIR = irqno;
	
}