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//See LICENSE for license details.
#include <stdint.h>
#include <stdio.h>
#include <unistd.h>
#include "platform.h"
#include "encoding.h"
extern int main(int argc, char** argv);
extern void trap_entry();
static unsigned long get_cpu_freq()
{
return 65000000;
}
unsigned long get_timer_freq()
{
return get_cpu_freq();
}
uint64_t get_timer_value()
{
#if __riscv_xlen == 32
while (1) {
uint32_t hi = read_csr(mcycleh);
uint32_t lo = read_csr(mcycle);
if (hi == read_csr(mcycleh))
return ((uint64_t)hi << 32) | lo;
}
#else
return read_csr(mcycle);
#endif
}
static void uart_init(size_t baud_rate)
{
GPIO_REG(GPIO_IOF_SEL) &= ~IOF0_UART0_MASK;
GPIO_REG(GPIO_IOF_EN) |= IOF0_UART0_MASK;
UART0_REG(UART_REG_DIV) = get_cpu_freq() / baud_rate - 1;
UART0_REG(UART_REG_TXCTRL) |= UART_TXEN;
}
#ifdef USE_PLIC
extern void handle_m_ext_interrupt();
#endif
#ifdef USE_M_TIME
extern void handle_m_time_interrupt();
#endif
uintptr_t handle_trap(uintptr_t mcause, uintptr_t epc)
{
if (0){
#ifdef USE_PLIC
// External Machine-Level interrupt from PLIC
} else if ((mcause & MCAUSE_INT) && ((mcause & MCAUSE_CAUSE) == IRQ_M_EXT)) {
handle_m_ext_interrupt();
#endif
#ifdef USE_M_TIME
// External Machine-Level interrupt from PLIC
} else if ((mcause & MCAUSE_INT) && ((mcause & MCAUSE_CAUSE) == IRQ_M_TIMER)){
handle_m_time_interrupt();
#endif
}
else {
write(1, "Unhandled Trap:\n", 16);
_exit(1 + mcause);
}
return epc;
}
void _init()
{
#ifndef NO_INIT
uart_init(115200);
printf("core freq at %d Hz\n", get_cpu_freq());
write_csr(mtvec, &trap_entry);
#endif
}
void _fini()
{
}
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