CPU: Created a basic CPU that can run a loop, along with several small bugfixes elsewhere to make it work

This commit is contained in:
(Tim) Efthimis Kritikos 2024-02-03 22:54:20 +00:00
parent bd84eb5b2e
commit 5595ea91f2
8 changed files with 239 additions and 11 deletions

1
.gitignore vendored
View File

@ -1,3 +1,4 @@
*.o
first
test.rom
make.deps

View File

@ -2,7 +2,13 @@ QUIET=1
all:first
OBJECT_FILES=gui.o main.o simdata.o assembly.o
OBJECT_FILES=gui.o main.o simdata.o assembly.o cpu.o
make.deps: $(subst .o,.c,${OBJECT_FILES}) $(wildcard *.h)
@$(CC) -MM $(subst .o,.c,${OBJECT_FILES}) > make.deps
include make.deps
ifeq "${QUIET}" "1"
QUIET_CC = @echo ' CC '$@;

136
cpu.c Normal file
View File

@ -0,0 +1,136 @@
#include "simdata.h"
#include "cpu.h"
#include <stdlib.h>
struct fetch_data_t *malloc_fetch_data(){
return NULL;
}
void free_fetch_data(__attribute__((unused)) struct fetch_data_t *tofree){
}
int fetch(struct simdata_t *simdata){
simdata->decode_data->in_bytecode=(uint32_t)(simdata->RAM[simdata->PC])<<24|(uint32_t)(simdata->RAM[simdata->PC+1])<<16|(uint32_t)(simdata->RAM[simdata->PC+2])<<8|(uint32_t)(simdata->RAM[simdata->PC+3]);
simdata->PC+=4;
return 0;
}
struct decode_data_t *malloc_decode_data(){
return malloc(sizeof(struct decode_data_t));
}
void free_decode_data(struct decode_data_t *tofree){
free(tofree);
}
int decode(struct simdata_t *simdata){
uint16_t opcode;
switch((simdata->decode_data->in_bytecode&0xE0000000)>>29){
case 0:
opcode=(simdata->decode_data->in_bytecode&0x1F000000)>>24;
switch(opcode){
case 1:
simdata->exec_data->out_op->OP_ADDR=IMMEDIATE;
simdata->exec_data->out_op->data=simdata->decode_data->in_bytecode&0x00FFFFFF;
simdata->exec_data->EXEC_ACTION=JUMP;
break;
default:
return 1;
}
break;
case 1:
return 1;
break;
case 2:
return 1;
break;
default:
return 1;
}
return 0;
}
struct exec_data_t *malloc_exec_data(){
struct exec_data_t *ret;
ret=malloc(sizeof(struct exec_data_t));
if(!ret)
return 0;
ret->in_op1=malloc(sizeof(struct exec_op_t));
if(!ret->in_op1){
free(ret);
return 0;
}
ret->in_op2=malloc(sizeof(struct exec_op_t));
if(!ret->in_op2){
free(ret->in_op1);
free(ret);
return 0;
}
ret->out_op=malloc(sizeof(struct exec_op_t));
if(!ret->out_op){
free(ret->in_op1);
free(ret->in_op2);
free(ret);
return 0;
}
return ret;
}
void free_exec_data(struct exec_data_t *tofree){
free(tofree->in_op1);
free(tofree->in_op2);
free(tofree->out_op);
free(tofree);
}
int exec(struct simdata_t *simdata){
switch(simdata->exec_data->EXEC_ACTION){
case JUMP:
if(simdata->exec_data->out_op->OP_ADDR==IMMEDIATE)
simdata->PC=simdata->exec_data->out_op->data;
else
return 1;
break;
case EXEC_ALU:
return 1;
}
return 0;
}
int state=0;
int cpu_cycle_clock(struct simdata_t *simdata){
switch(state){
case 0: if( fetch(simdata) ) return 1; break;
case 1: if( decode(simdata) ) return 1; break;
case 2: if( exec(simdata) ) return 1; break;
}
if(state==2)
state=0;
else
state++;
return 0;
}
int cpu_simdata_malloc(struct simdata_t *simdata){
simdata->fetch_data=malloc_fetch_data();
simdata->decode_data=malloc_decode_data();
simdata->exec_data=malloc_exec_data();
if((simdata->fetch_data!=NULL)&&(simdata->decode_data!=NULL)&&(simdata->exec_data!=NULL))
return 1;
else
return 0;
}
void cpu_simdata_free(struct simdata_t *simdata){
free_fetch_data(simdata->fetch_data);
free_decode_data(simdata->decode_data);
free_exec_data(simdata->exec_data);
}

54
cpu.h Normal file
View File

@ -0,0 +1,54 @@
#ifndef CPU_HEADER
#include "simdata.h"
struct fetch_data_t{
};
struct decode_data_t{
uint32_t in_bytecode;
};
///// EXEC DATA STRUCTURES ///////
enum EXEC_ACTION_t {
EXEC_ALU,
JUMP
};
enum ALU_OP_t {
ALU_ADD,
ALU_SUB,
ALU_SL,
ALU_SR,
ALU_CMP
};
enum OP_ADDR_t {
IMMEDIATE,
REGISTER,
};
struct exec_op_t {
enum OP_ADDR_t OP_ADDR;
uint32_t data;
};
struct exec_data_t {
enum EXEC_ACTION_t EXEC_ACTION;
enum ALU_OP_t ALU_OP;
struct exec_op_t *in_op1;
struct exec_op_t *in_op2;
struct exec_op_t *out_op;
};
void cpu_simdata_free(struct simdata_t *simdata);
int cpu_simdata_malloc(struct simdata_t *simdata);
int cpu_cycle_clock(struct simdata_t *simdata);
#endif
#define CPU_HEADER

7
gui.c
View File

@ -170,6 +170,7 @@ int gui_error(char *str){
}
int update_general_disas(struct simdata_t *simdata){
wclear(general_disas);
int width,height;
getmaxyx(general_disas,height,width);
box(general_disas, 0 , 0);
@ -219,6 +220,7 @@ int update_general_disas(struct simdata_t *simdata){
}
int update_general_stack(struct simdata_t *simdata){
wclear(general_stack);
int width,height;
getmaxyx(general_stack,height,width);
box(general_stack, 0 , 0);
@ -275,6 +277,7 @@ int update_general_stack(struct simdata_t *simdata){
}
int update_general_memdump(struct simdata_t *simdata){
wclear(general_memdump);
int width,height;
getmaxyx(general_memdump,height,width);
box(general_memdump, 0 , 0);
@ -292,7 +295,7 @@ int update_general_memdump(struct simdata_t *simdata){
wprintw(general_memdump,"%06x ",ADDRESS);
uint32_t temp_address=ADDRESS;
for (int i=0;i<n;i++){
if(ADDRESS>=simdata->PC&&ADDRESS<=simdata->PC+4)
if(ADDRESS>=simdata->PC&&ADDRESS<=simdata->PC+3)
wattron(general_memdump,A_BOLD);
else
wattroff(general_memdump,A_BOLD);
@ -301,7 +304,7 @@ int update_general_memdump(struct simdata_t *simdata){
}
ADDRESS=temp_address;
for (int i=0;i<n;i++){
if(ADDRESS>=simdata->PC&&ADDRESS<=simdata->PC+4)
if(ADDRESS>=simdata->PC&&ADDRESS<=simdata->PC+3)
wattron(general_memdump,A_BOLD);
else
wattroff(general_memdump,A_BOLD);

36
main.c
View File

@ -24,6 +24,7 @@
#include <unistd.h>
#include <errno.h>
#include "assembly.h"
#include "cpu.h"
void help(char* progname){
printf("Usage: %s -i <file> \n", progname);
@ -71,6 +72,10 @@ int main(int argc, char* argd[] ){
FILE* rom=fopen(infile,"r");
struct simdata_t *simdata = init_simdata();
if(!simdata){
printf("Couldn't allocate memory\n");
return 1;
}
if ( assemble != NULL ){
/* RUN ASSEMBLER */
@ -127,7 +132,7 @@ int main(int argc, char* argd[] ){
fseek(rom, 0, SEEK_SET);
if(!simdata){
gui_error("failed to initialise simdata");
gui_error("failed to initialise simdata\n");
fclose(rom);
free_simdata(simdata);
return 1;
@ -144,25 +149,42 @@ int main(int argc, char* argd[] ){
/// INITIALISE GUI ///
if(start_gui()){
printf("Failed on start_gui()\n");
cpu_simdata_free(simdata);
free_simdata(simdata);
return 1;
}
update_gui(simdata);
cpu_simdata_malloc(simdata);
if(gui_continue_request()){
end_gui();
printf("Failed on gui_continue_request()\n");
free_simdata(simdata);
return 1;
while(1){
update_gui(simdata);
if(gui_continue_request()){
end_gui();
printf("Failed on gui_continue_request()\n");
cpu_simdata_free(simdata);
free_simdata(simdata);
return 1;
}
if(cpu_cycle_clock(simdata)){
cpu_simdata_free(simdata);
free_simdata(simdata);
end_gui();
printf("Failed to execute instruction\n");
return 1;
}
}
if(end_gui()){
printf("Failed on end_gui()\n");
cpu_simdata_free(simdata);
free_simdata(simdata);
return 1;
}
cpu_simdata_free(simdata);
free_simdata(simdata);
}
return 0;

View File

@ -6,6 +6,9 @@ struct simdata_t{
uint8_t *RAM;
uint32_t PC;
uint32_t SP;
struct fetch_data_t *fetch_data;
struct decode_data_t *decode_data;
struct exec_data_t *exec_data;
};
struct simdata_t *init_simdata();
@ -17,5 +20,6 @@ enum CPU_STATE_t{
SINGLE_STEPPING,
STOPPED
};
#endif
#define SIMDATA_HEADER

View File

@ -1,4 +1,6 @@
JMP $ABCDEF
JMP $000008
SL %R7
JMP $000000
JMP,NZ $DEADBA
JMP,C $EEEEEF
SL %R7