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// See LICENSE for license details.
#include <stdio.h>
#include "shared.h"
#include "plic.h"
#include <string.h>
void reset_demo (void);
// Structures for registering different interrupt handlers
// for different parts of the application.
typedef void (*function_ptr_t) (void);
void no_interrupt_handler (void) {};
function_ptr_t g_ext_interrupt_handlers[9];
function_ptr_t g_m_timer_interrupt_handler = no_interrupt_handler;
// Instance data for the PLIC.
plic_instance_t g_plic;
// Simple variables for LEDs, buttons, etc.
volatile unsigned int* g_outputs = (unsigned int *) (GPIO_BASE_ADDR + GPIO_OUT_OFFSET);
volatile unsigned int* g_inputs = (unsigned int *) (GPIO_BASE_ADDR + GPIO_IN_OFFSET);
volatile unsigned int* g_tristates = (unsigned int *) (GPIO_BASE_ADDR + GPIO_TRI_OFFSET);
/*Entry Point for PLIC Interrupt Handler*/
void handle_m_ext_interrupt(){
plic_source int_num = PLIC_claim_interrupt(&g_plic);
if ((int_num >=1 ) && (int_num <= 8)) {
g_ext_interrupt_handlers[int_num]();
}
else {
_exit(1 + (uintptr_t) int_num);
}
PLIC_complete_interrupt(&g_plic, int_num);
}
/*Entry Point for Machine Timer Interrupt Handler*/
void handle_m_time_interrupt(){
clear_csr(mie, MIP_MTIP);
// Reset the timer for 3s in the future.
// This also clears the existing timer interrupt.
volatile uint64_t * mtime = (uint64_t*) MTIME_ADDR;
volatile uint64_t * mtimecmp = (uint64_t*) MTIMECMP_BASE_ADDR;
uint64_t now = *mtime;
uint64_t then = now + 3 * CLOCK_FREQUENCY / RTC_PRESCALER;
*mtimecmp = then;
// read the current value of the LEDS and invert them.
uint32_t leds = *g_outputs;
*g_outputs = (~leds) & ((0xF << RED_LEDS_OFFSET) |
(0xF << GREEN_LEDS_OFFSET) |
(0xF << BLUE_LEDS_OFFSET));
// Re-enable the timer interrupt.
set_csr(mie, MIP_MTIP);
}
/*Entry Point for Machine Timer Interrupt Handler*/
void handle_m_timer_interrupt(){
g_m_timer_interrupt_handler();
}
const char * instructions_msg = " \
\n\
SIFIVE, INC.\n\
\n\
5555555555555555555555555\n\
5555 5555\n\
5555 5555\n\
5555 5555\n\
5555 5555555555555555555555\n\
5555 555555555555555555555555\n\
5555 5555\n\
5555 5555\n\
5555 5555\n\
5555555555555555555555555555 55555\n\
55555 555555555 55555\n\
55555 55555 55555\n\
55555 5 55555\n\
55555 55555\n\
55555 55555\n\
55555 55555\n\
55555 55555\n\
55555 55555\n\
555555555\n\
55555\n\
5\n\
\n\
SiFive E-Series Coreplex Demo on Arty Board\n \
\n\
";
void print_instructions() {
write (STDOUT_FILENO, instructions_msg, strlen(instructions_msg));
}
void button_0_handler(void) {
// Rainbow LEDs!
* g_outputs = (0x9 << RED_LEDS_OFFSET) | (0xA << GREEN_LEDS_OFFSET) | (0xC << BLUE_LEDS_OFFSET);
};
void reset_demo (){
// Disable the machine & timer interrupts until setup is done.
clear_csr(mie, MIP_MEIP);
clear_csr(mie, MIP_MTIP);
g_ext_interrupt_handlers[INT_DEVICE_BUTTON_0] = button_0_handler;
g_ext_interrupt_handlers[INT_DEVICE_BUTTON_1] = no_interrupt_handler;
g_ext_interrupt_handlers[INT_DEVICE_BUTTON_2] = no_interrupt_handler;
g_ext_interrupt_handlers[INT_DEVICE_BUTTON_3] = no_interrupt_handler;
g_ext_interrupt_handlers[INT_DEVICE_JA_7] = no_interrupt_handler;
g_ext_interrupt_handlers[INT_DEVICE_JA_8] = no_interrupt_handler;
g_ext_interrupt_handlers[INT_DEVICE_JA_9] = no_interrupt_handler;
g_ext_interrupt_handlers[INT_DEVICE_JA_10] = no_interrupt_handler;
print_instructions();
PLIC_enable_interrupt (&g_plic, INT_DEVICE_BUTTON_0);
// Set the machine timer to go off in 3 seconds.
// The
volatile uint64_t * mtime = (uint64_t*) MTIME_ADDR;
volatile uint64_t * mtimecmp = (uint64_t*) MTIMECMP_BASE_ADDR;
uint64_t now = *mtime;
uint64_t then = now + 3*CLOCK_FREQUENCY / RTC_PRESCALER;
*mtimecmp = then;
// Enable the Machine-External bit in MIE
set_csr(mie, MIP_MEIP);
// Enable the Machine-Timer bit in MIE
set_csr(mie, MIP_MTIP);
// Enable interrupts in general.
set_csr(mstatus, MSTATUS_MIE);
}
int main(int argc, char **argv)
{
// Set up the GPIOs such that the inputs' tristate are set.
// The boot ROM actually does this, but still good.
* g_tristates = (0xF << BUTTONS_OFFSET) | (0xF << SWITCHES_OFFSET) | (0xF << JA_IN_OFFSET);
* g_outputs = (0xF << RED_LEDS_OFFSET);
/**************************************************************************
* Set up the PLIC
*
*************************************************************************/
PLIC_init(&g_plic, PLIC_BASE_ADDR, PLIC_NUM_SOURCES, PLIC_NUM_PRIORITIES);
reset_demo();
while (1);
return 0;
}
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