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artiq/soc/runtime/main.c

187 lines
3.2 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <irq.h>
#include <uart.h>
#include <console.h>
#include <system.h>
#include <generated/csr.h>
#include "elf_loader.h"
enum {
MSGTYPE_REQUEST_IDENT = 0x01,
MSGTYPE_LOAD_KERNEL = 0x02,
MSGTYPE_KERNEL_FINISHED = 0x03,
MSGTYPE_RPC_REQUEST = 0x04,
};
static int receive_int(void)
{
unsigned int r;
int i;
r = 0;
for(i=0;i<4;i++) {
r <<= 8;
r |= (unsigned char)uart_read();
}
return r;
}
static char receive_char(void)
{
return uart_read();
}
static void send_int(int x)
{
int i;
for(i=0;i<4;i++) {
uart_write((x & 0xff000000) >> 24);
x <<= 8;
}
}
static void send_sint(short int i)
{
uart_write((i >> 8) & 0xff);
uart_write(i & 0xff);
}
static void send_char(char c)
{
uart_write(c);
}
static void receive_sync(void)
{
char c;
int recognized;
recognized = 0;
while(recognized < 4) {
c = uart_read();
if(c == 0x5a)
recognized++;
else
recognized = 0;
}
}
static void send_sync(void)
{
send_int(0x5a5a5a5a);
}
static int ident_and_download_kernel(void *buffer, int maxlength)
{
int length;
int i;
char msgtype;
unsigned char *_buffer = buffer;
while(1) {
receive_sync();
msgtype = receive_char();
if(msgtype == MSGTYPE_REQUEST_IDENT) {
send_int(0x41524f52); /* "AROR" - ARTIQ runtime on OpenRISC */
send_int(1000000000000LL/identifier_frequency_read()); /* RTIO clock period in picoseconds */
} else if(msgtype == MSGTYPE_LOAD_KERNEL) {
length = receive_int();
if(length > maxlength)
return -1;
for(i=0;i<length;i++)
_buffer[i] = receive_char();
send_char(0x4f); /* kernel reception OK */
return length;
} else
return -1;
}
}
static int rpc(int rpc_num, int n_args, ...)
{
send_sync();
send_char(MSGTYPE_RPC_REQUEST);
send_sint(rpc_num);
send_char(n_args);
va_list args;
va_start(args, n_args);
while(n_args--)
send_int(va_arg(args, int));
va_end(args);
return receive_int();
}
static void gpio_set(int channel, int value)
{
static int csr_value;
if(value)
csr_value |= 1 << channel;
else
csr_value &= ~(1 << channel);
leds_out_write(csr_value);
}
static void rtio_set(int timestamp, int channel, int value)
{
rtio_chan_sel_write(channel);
rtio_o_timestamp_write(timestamp);
rtio_o_value_write(value);
while(!rtio_o_writable_read());
rtio_o_we_write(1);
}
static void rtio_sync(int channel)
{
rtio_chan_sel_write(channel);
while(rtio_o_level_read() != 0);
}
static const struct symbol syscalls[] = {
{"__syscall_rpc", rpc},
{"__syscall_gpio_set", gpio_set},
{"__syscall_rtio_set", rtio_set},
{"__syscall_rtio_sync", rtio_sync},
{NULL, NULL}
};
typedef void (*kernel_function)(void);
int main(void)
{
unsigned char kbuf[256*1024];
unsigned char kcode[256*1024];
kernel_function k = (kernel_function)kcode;
int length;
irq_setmask(0);
irq_setie(1);
uart_init();
puts("ARTIQ runtime built "__DATE__" "__TIME__"\n");
while(1) {
length = ident_and_download_kernel(kbuf, sizeof(kbuf));
if(length > 0) {
if(load_elf(syscalls, kbuf, length, kcode, sizeof(kcode))) {
flush_cpu_icache();
rtio_reset_write(0);
k();
rtio_reset_write(1);
send_sync();
send_char(MSGTYPE_KERNEL_FINISHED);
}
}
}
return 0;
}