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// See LICENSE for license details.
#include <stdio.h>
#include <stdlib.h>
#include "platform.h"
#include <string.h>
#include "plic/plic_driver.h"
#include "encoding.h"
#include <unistd.h>
#ifndef _SIFIVE_COREPLEXIP_ARTY_H
#error 'global_interrupts' demo only supported for Coreplex IP Eval Kits
#endif
// Global Instance data for the PLIC
// for use by the PLIC Driver.
plic_instance_t g_plic;
// Structures for registering different interrupt handlers
// for different parts of the application.
typedef void (*interrupt_function_ptr_t) (void);
//array of function pointers which contains the PLIC
//interrupt handlers
interrupt_function_ptr_t g_ext_interrupt_handlers[PLIC_NUM_INTERRUPTS];
const char * instructions_msg = " \
\n\
SIFIVE, INC.\n\
E31/E51 Coreplex IP Eval Kit 'vectored_interrupts' demo. \n\
\n\
This demo demonstrates Vectored Interrupts capabilities of\n\
the E31/E51 Coreplex. The vector table is defined in \n\
bsp/env/ventry.S \n\
Button 0 is a global external interrupt routed to the PLIC.\n\
Button 1 is a local interrupt.\n\
\n";
void print_instructions() {
write (STDOUT_FILENO, instructions_msg, strlen(instructions_msg));
}
void set_timer() {
volatile uint64_t * mtime = (uint64_t*) (CLINT_CTRL_ADDR + CLINT_MTIME);
volatile uint64_t * mtimecmp = (uint64_t*) (CLINT_CTRL_ADDR + CLINT_MTIMECMP);
uint64_t now = *mtime;
uint64_t then = now + 1*RTC_FREQ;
*mtimecmp = then;
set_csr(mie, MIP_MTIP);
}
/*Entry Point for Machine Timer Interrupt Handler*/
/*called from bsp/env/ventry.s */
void handle_m_time_interrupt(){
static uint32_t onoff=1;
clear_csr(mie, MIP_MTIP);
// Set Green LED
if(onoff) {
GPIO_REG(GPIO_OUTPUT_VAL) |= (0x1 << GREEN_LED_OFFSET) ;
onoff=0;
}else {
GPIO_REG(GPIO_OUTPUT_VAL) &= ~((0x1 << GREEN_LED_OFFSET)) ;
onoff=1;
}
set_timer();
//re-enable button1 irq
set_csr(mie, MIP_MLIP(LOCAL_INT_BTN_1));
}
/*Synchronous Trap Handler*/
/*called from bsp/env/ventry.s */
void handle_sync_trap(uintptr_t mcause, uintptr_t epc ) {
write(1, "vUnhandled Trap:\n", 16);
_exit(1 + mcause);
}
/*Entry Point for PLIC Interrupt Handler*/
/*called from bsp/env/ventry.s */
void handle_m_external_interrupt(){
printf("In PLIC handler\n");
plic_source int_num = PLIC_claim_interrupt(&g_plic);
if ((int_num >=1 ) && (int_num < PLIC_NUM_INTERRUPTS)) {
g_ext_interrupt_handlers[int_num]();
}
else {
exit(1 + (uintptr_t) int_num);
}
PLIC_complete_interrupt(&g_plic, int_num);
}
//default empty PLIC handler
void invalid_global_isr() {
printf("Unexpected global interrupt!\n");
}
/* b0 global interrupt isr */
/*called from handle_m_external_interrupt */
void button_0_handler() {
static uint32_t onoff=1;
// Set Green LED
printf("In Button 0 handler\n");
if(onoff) {
GPIO_REG(GPIO_OUTPUT_VAL) |= (0x1 << BLUE_LED_OFFSET) ;
onoff=0;
}else {
GPIO_REG(GPIO_OUTPUT_VAL) &= ~((0x1 << BLUE_LED_OFFSET)) ;
onoff=1;
}
//clear irq - interrupt pending register is write 1 to clear
GPIO_REG(GPIO_FALL_IP) |= (1<<BUTTON_0_OFFSET);
}
/*b1 local vectored irq handler */
/*called from bsp/env/ventry.s */
void handle_local_interrupt5() {
static uint32_t onoff=1;
// Set Green LED
printf("In Button 1 handler\n");
if(onoff) {
GPIO_REG(GPIO_OUTPUT_VAL) |= (0x1 << RED_LED_OFFSET) ;
onoff=0;
}else {
GPIO_REG(GPIO_OUTPUT_VAL) &= ~((0x1 << RED_LED_OFFSET)) ;
onoff=1;
}
//debounce by turning off until next timer tick
clear_csr(mie, MIP_MLIP(LOCAL_INT_BTN_1));
}
/*configures Button0 as a global gpio irq*/
void b0_irq_init() {
//dissable hw io function
GPIO_REG(GPIO_IOF_EN ) &= ~(1 << BUTTON_0_OFFSET);
//set to input
GPIO_REG(GPIO_INPUT_EN) |= (1<<BUTTON_0_OFFSET);
GPIO_REG(GPIO_PULLUP_EN) |= (1<<BUTTON_0_OFFSET);
//set to interrupt on falling edge
GPIO_REG(GPIO_FALL_IE) |= (1<<BUTTON_0_OFFSET);
PLIC_init(&g_plic,
PLIC_CTRL_ADDR,
PLIC_NUM_INTERRUPTS,
PLIC_NUM_PRIORITIES);
PLIC_enable_interrupt (&g_plic, INT_DEVICE_BUTTON_0);
PLIC_set_priority(&g_plic, INT_DEVICE_BUTTON_0, 2);
g_ext_interrupt_handlers[INT_DEVICE_BUTTON_0] = button_0_handler;
}
/*configures Button1 as a local interrupt*/
void b1_irq_init() {
//enable the interrupt
set_csr(mie, MIP_MLIP(LOCAL_INT_BTN_1));
}
/*turn down the brightness, and configure GPIO */
void led_init() {
// Make sure people aren't blinded by LEDs connected here.
PWM0_REG(PWM_CMP0) = 0xFE;
PWM0_REG(PWM_CMP1) = 0xFF;
PWM0_REG(PWM_CMP2) = 0xFF;
PWM0_REG(PWM_CMP3) = 0xFF;
// Set up RGB LEDs for a visual.
GPIO_REG(GPIO_OUTPUT_EN) |= ((0x1<< RED_LED_OFFSET)| (0x1<< GREEN_LED_OFFSET)| (0x1<< BLUE_LED_OFFSET));
GPIO_REG(GPIO_OUTPUT_VAL) &= ~((0x1<< RED_LED_OFFSET) | (0x1<< GREEN_LED_OFFSET) | (0x1<< BLUE_LED_OFFSET));
}
int main(int argc, char **argv)
{
//setup default global interrupt handler
for (int gisr = 0; gisr < PLIC_NUM_INTERRUPTS; gisr++){
g_ext_interrupt_handlers[PLIC_NUM_INTERRUPTS] = invalid_global_isr;
}
print_instructions();
led_init();
b0_irq_init();
b1_irq_init();
// Set up machine timer interrupt.
set_timer();
// Enable Global (PLIC) interrupts.
set_csr(mie, MIP_MEIP);
// Enable all interrupts
set_csr(mstatus, MSTATUS_MIE);
while(1){
asm volatile ("wfi");
}
return 0;
}
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