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#include <stddef.h>
#include <stdio.h>
#include "encoding.h"
#include "platform.h"
#include "event.h"
#include "timer.h"
#define MIN(X, Y) (((X) < (Y)) ? (X) : (Y))
#define MAX(X, Y) (((X) > (Y)) ? (X) : (Y))
static eos_timer_fptr_t timer_ext_handler = NULL;
volatile uint64_t timer_next = 0;
volatile uint64_t timer_next_evt = 0;
void handle_m_time_interrupt(void) {
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;
if (timer_next && (timer_next <= now)) {
uint32_t next = timer_ext_handler();
if (next) {
timer_next = now + next;
} else {
timer_next = 0;
}
}
if (timer_next_evt && (timer_next_evt <= now)) {
eos_evtq_push(EOS_EVT_TIMER, NULL, 0);
timer_next_evt = 0;
}
*mtimecmp = (timer_next && timer_next_evt) ? MIN(timer_next, timer_next_evt) : (timer_next ? timer_next : timer_next_evt);
if (*mtimecmp == 0) clear_csr(mie, MIP_MTIP);
}
void eos_timer_init(void) {
volatile uint64_t *mtimecmp = (uint64_t *) (CLINT_CTRL_ADDR + CLINT_MTIMECMP);
*mtimecmp = 0;
clear_csr(mie, MIP_MTIP);
}
void eos_timer_set(uint32_t tick, unsigned char is_evt) {
volatile uint64_t *mtime = (uint64_t *) (CLINT_CTRL_ADDR + CLINT_MTIME);
volatile uint64_t *mtimecmp = (uint64_t *) (CLINT_CTRL_ADDR + CLINT_MTIMECMP);
clear_csr(mstatus, MSTATUS_MIE);
uint64_t now = *mtime;
uint64_t then = *mtimecmp;
uint64_t next = now + tick;
if (is_evt) {
if ((timer_next_evt == 0) || (next < timer_next_evt)) timer_next_evt = next;
next = timer_next ? MIN(timer_next, timer_next_evt) : timer_next_evt;
} else if (timer_ext_handler) {
if ((timer_next == 0) || (next < timer_next)) timer_next = next;
next = timer_next_evt ? MIN(timer_next, timer_next_evt) : timer_next;
}
if ((then == 0) || (next < then)) *mtimecmp = next;
if (then == 0) set_csr(mie, MIP_MTIP);
set_csr(mstatus, MSTATUS_MIE);
}
void eos_timer_clear(unsigned char is_evt) {
volatile uint64_t *mtimecmp = (uint64_t *) (CLINT_CTRL_ADDR + CLINT_MTIMECMP);
clear_csr(mstatus, MSTATUS_MIE);
if (is_evt) {
timer_next_evt = 0;
*mtimecmp = timer_next;
} else {
timer_next = 0;
*mtimecmp = timer_next_evt;
}
if (*mtimecmp == 0) clear_csr(mie, MIP_MTIP);
set_csr(mstatus, MSTATUS_MIE);
}
void eos_timer_set_handler(eos_timer_fptr_t handler) {
clear_csr(mstatus, MSTATUS_MIE);
timer_ext_handler = handler;
set_csr(mstatus, MSTATUS_MIE);
}
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