gbdb: remove some conditionals from mem_read()

By reading directly from a "RAM" array, and copying in the cart data
over the old bootrom.

Also, some other fixups because I'm too lazy to properly split patches
for a personal project.

gbdb_boot_test

@@ -1,3 +1,4 @@
+load ../harvest_moon.gb
 bootrom ../bootrom.gb
 echo Running test...
 set quiet 1

src/apps/gbdb.c

@@ -19,7 +19,7 @@
 #include "common/tri.h"
 
 #define INPUT_MAX_LEN 512
-#define MAX_BREAKPTS 2 /* Should be plenty for anyone */
+#define MAX_BREAKPTS 16 /* Should be plenty for anyone */
 #define MAX_RAM_LEN (1 << 20) /* Up to 8Mb Cartridge */
 #define UNMAP_BOOTROM_ADDR 0xff50
 
@@ -46,6 +46,7 @@ static struct lr35902_state cpu;
 static struct gb_video video;
 
 static unsigned char bootrom[0x100] = {0};
+static unsigned char cart_low[0x100] = {0};
 
 static int bootrom_mapped = 1;
 
@@ -97,12 +98,6 @@ static uint8_t mem_read(struct lr35902_state *cpu, uint16_t addr)
 {
 
 	switch (addr) {
-	case 0 ... 0x100-1:
-		if (bootrom_mapped) {
-			return bootrom[addr];
-		} else {
-			return ram[addr];
-		}
 	case 0xFF40 ... 0xFF4B:
 		return gb_video_mem_read(&video, addr);
 	default:
@@ -117,6 +112,7 @@ static void mem_write(struct lr35902_state *cpu, uint16_t addr, uint8_t val)
 	case UNMAP_BOOTROM_ADDR:
 		if (val == 1) {
 			bootrom_mapped = 0;
+			memcpy(ram, cart_low, sizeof(cart_low));
 			gb_log("bootrom unmapped\n");
 		}
 		break;
@@ -375,7 +371,7 @@ static void assert(char *arg_list)
 	return;
 fail:
 	printf("ASSERT: %s %s %s\n", val0_str, operator_str, val1_str);
-	printf("%s=%ld, %s=%ld\n", val0_str, val0, val1_str, val1);
+	printf("%s=%lld, %s=%lld\n", val0_str, val0, val1_str, val1);
 	regs(NULL);
 	stats(NULL);
 	exit(1);
@@ -449,6 +445,8 @@ static void load(char *arg_list)
 
 	strip_newline(token);
 	load_file_to_buffer(token, ram, sizeof(ram));
+	load_file_to_buffer(token, cart_low, sizeof(cart_low));
+
 }
 
 static void load_bootrom(char *arg_list)
@@ -461,6 +459,7 @@ static void load_bootrom(char *arg_list)
 
 	strip_newline(token);
 	load_file_to_buffer(token, bootrom, sizeof(bootrom));
+	load_file_to_buffer(token, ram, sizeof(bootrom));
 }
 
 

src/gbemu/cpu.c

@@ -326,12 +326,10 @@ void lr35902_cycle(struct lr35902_state *cpu)
 
 	if (cpu->stall_cycles > 0) {
 		cpu->stall_cycles--;
-		if (cpu->stall_cycles == 0) {
-			cpu->metrics.retired_instrs++;
-		}
 		return;
 	}
 
+	cpu->metrics.retired_instrs++;
 	inst = cpu->mem_read(cpu, cpu->pc++);
 	cpu->stall_cycles = op_extra_cycles[inst];
 

src/gbemu/video.c

@@ -14,16 +14,15 @@ void gb_video_init(struct gb_video *video)
 
 void gb_video_cycle(struct gb_video *video)
 {
+	if (video->line_counter <  CYCLES_PER_LINE - 1) {
 		video->line_counter++;
-
+	} else {
-	if (video->line_counter >= CYCLES_PER_LINE) {
 		video->line_counter = 0;
 		video->curline += 1;
 		if (video->curline > LCD_Y_MAX) {
 			video->curline = 0;
 		}
 	}
-
 }
 
 uint8_t gb_video_mem_read(struct gb_video *video, uint16_t addr)