feat: Update nes/gbc/sms/genesis emulators to use shared memory

CMakeLists.txt

@@ -1,6 +1,6 @@
 # The following lines of boilerplate have to be in your project's CMakeLists
 # in this exact order for cmake to work correctly
-cmake_minimum_required(VERSION 3.5)
+cmake_minimum_required(VERSION 3.15)
 
 include($ENV{IDF_PATH}/tools/cmake/project.cmake)
 

components/box-emu/include/box-emu.hpp

@@ -151,6 +151,7 @@ class BoxEmu : public espp::BaseComponent {
   /////////////////////////////////////////////////////////////////////////////
 
   bool initialize_video();
+  void clear_screen();
   void display_size(size_t width, size_t height);
   void native_size(size_t width, size_t height, int pitch = -1);
   void palette(const uint16_t *palette, size_t size = 256);

components/box-emu/src/box-emu.cpp

@@ -467,6 +467,11 @@ bool BoxEmu::initialize_video() {
   return true;
 }
 
+void BoxEmu::clear_screen() {
+  static int buffer = 0;
+  xQueueSend(video_queue_, &buffer, 10);
+}
+
 void BoxEmu::display_size(size_t width, size_t height) {
   display_width_ = width;
   display_height_ = height;
@@ -717,13 +722,29 @@ bool BoxEmu::video_task_callback(std::mutex &m, std::condition_variable& cv, boo
     return false;
   }
   static constexpr int num_lines_to_write = num_rows_in_framebuffer;
-  auto &box = Bsp::get();
+  static auto &box = Bsp::get();
+  static const uint16_t *vram0 = (uint16_t*)box.vram0();
+  static const uint16_t *vram1 = (uint16_t*)box.vram1();
   static uint16_t vram_index = 0; // has to be static so that it persists between calls
   const int _x_offset = x_offset();
   const int _y_offset = y_offset();
   const uint16_t* _palette = palette();
-  uint16_t *vram0 = (uint16_t*)box.vram0();
-  uint16_t *vram1 = (uint16_t*)box.vram1();
+  // special case: if _frame_ptr is null, then we ignore all palette, scaling,
+  // etc. and simply fill the screen with 0
+  if (_frame_ptr == nullptr) {
+    for (int y=0; y<lcd_height(); y+= num_lines_to_write) {
+      Pixel* _buf = (Pixel*)((uint32_t)vram0 * (vram_index ^ 0x01) + (uint32_t)vram1 * vram_index);
+      vram_index = vram_index ^ 0x01;
+      int num_lines = std::min<int>(num_lines_to_write, lcd_height()-y);
+      // memset the buffer to 0
+      memset(_buf, 0, lcd_width() * num_lines * sizeof(Pixel));
+      box.write_lcd_frame(0, y + _y_offset, lcd_width(), num_lines, (uint8_t*)&_buf[0]);
+    }
+
+    // now return
+    return false;
+  }
+
   if (is_native()) {
     if (has_palette()) {
       for (int y=0; y<display_height_; y+= num_lines_to_write) {

components/gbc/CMakeLists.txt

@@ -3,7 +3,7 @@ idf_component_register(
   SRC_DIRS "src" "gnuboy/src"
   PRIV_INCLUDE_DIRS "gnuboy/include"
   # LDFRAGMENTS "linker.lf"
-  REQUIRES "box-emu" "statistics"
+  REQUIRES "box-emu" "statistics" "shared_memory"
   )
 
 target_compile_options(${COMPONENT_LIB} PRIVATE -Wno-misleading-indentation -Wno-implicit-fallthrough -Wno-unused-function -Wno-unused-variable -Wno-discarded-qualifiers)

components/gbc/gnuboy/include/gnuboy/cpu.h

@@ -25,7 +25,7 @@ struct cpu
 	int snd;
 };
 
-extern struct cpu cpu;
+extern struct cpu *cpu;
 
 
 void cpu_timers(int cnt);

components/gbc/gnuboy/include/gnuboy/cpuregs.h

@@ -14,33 +14,33 @@
 #define W(r) ((r).w[LO])
 #define DW(r) ((r).d)
 
-#define A HB(cpu.af)
-#define F LB(cpu.af)
-#define B HB(cpu.bc)
-#define C LB(cpu.bc)
-#define D HB(cpu.de)
-#define E LB(cpu.de)
-#define H HB(cpu.hl)
-#define L LB(cpu.hl)
-
-#define AF W(cpu.af)
-#define BC W(cpu.bc)
-#define DE W(cpu.de)
-#define HL W(cpu.hl)
-
-#define PC W(cpu.pc)
-#define SP W(cpu.sp)
-
-#define xAF DW(cpu.af)
-#define xBC DW(cpu.bc)
-#define xDE DW(cpu.de)
-#define xHL DW(cpu.hl)
-
-#define xPC DW(cpu.pc)
-#define xSP DW(cpu.sp)
-
-#define IMA cpu.ima
-#define IME cpu.ime
+#define A HB(cpu->af)
+#define F LB(cpu->af)
+#define B HB(cpu->bc)
+#define C LB(cpu->bc)
+#define D HB(cpu->de)
+#define E LB(cpu->de)
+#define H HB(cpu->hl)
+#define L LB(cpu->hl)
+
+#define AF W(cpu->af)
+#define BC W(cpu->bc)
+#define DE W(cpu->de)
+#define HL W(cpu->hl)
+
+#define PC W(cpu->pc)
+#define SP W(cpu->sp)
+
+#define xAF DW(cpu->af)
+#define xBC DW(cpu->bc)
+#define xDE DW(cpu->de)
+#define xHL DW(cpu->hl)
+
+#define xPC DW(cpu->pc)
+#define xSP DW(cpu->sp)
+
+#define IMA cpu->ima
+#define IME cpu->ime
 #define IF R_IF
 #define IE R_IE
 

components/gbc/gnuboy/include/gnuboy/lcd.h

@@ -13,7 +13,7 @@ struct vissprite
 	//byte pad[2]; //6
 };
 
-struct scan
+struct gbc_scan
 {
 	int bg[64];
 	int wnd[64];
@@ -45,7 +45,7 @@ struct lcd
 };
 
 extern struct lcd lcd;
-extern struct scan scan;
+extern struct gbc_scan *scan;
 
 
 void lcd_begin();

components/gbc/gnuboy/include/gnuboy/loader.h

@@ -22,6 +22,6 @@ int sram_save();
 void state_load(int n);
 void state_save(int n);
 
-
+extern unsigned char *gbc_filebuf;
 
 #endif

components/gbc/gnuboy/src/cpu.c

@@ -15,12 +15,6 @@
 #include "gnuboy/asm.h"
 #endif
 
-
-struct cpu cpu;
-
-
-
-
 #define ZFLAG(n) ( (n) ? 0 : FZ )
 #define HFLAG(n) ( (n) ? 0 : FH )
 #define CFLAG(n) ( (n) ? 0 : FC )
@@ -231,7 +225,7 @@ label: op(b); break;
 #define RET ( POP(PC) )
 
 #define EI ( IMA = 1 )
-#define DI ( cpu.halt = IMA = IME = 0 )
+#define DI ( cpu->halt = IMA = IME = 0 )
 
 
 
@@ -251,13 +245,13 @@ label: op(b); break;
 
 void cpu_reset()
 {
-	cpu.speed = 0;
-	cpu.halt = 0;
-	cpu.div = 0;
-	cpu.tim = 0;
+	cpu->speed = 0;
+	cpu->halt = 0;
+	cpu->div = 0;
+	cpu->tim = 0;
 	/* set lcdc ahead of cpu by 19us; see A */
 	/* FIXME: leave value at 0, use lcdc_trans() to actually send lcdc ahead */
-	cpu.lcdc = 40;
+	cpu->lcdc = 40;
 
 	IME = 0;
 	IMA = 0;
@@ -281,11 +275,11 @@ void cpu_reset()
 	handle differences in place */
 void div_advance(int cnt)
 {
-	cpu.div += (cnt<<1);
-	if (cpu.div >= 256)
+	cpu->div += (cnt<<1);
+	if (cpu->div >= 256)
 	{
-		R_DIV += (cpu.div >> 8);
-		cpu.div &= 0xff;
+		R_DIV += (cpu->div >> 8);
+		cpu->div &= 0xff;
 	}
 }
 
@@ -302,12 +296,12 @@ void timer_advance(int cnt)
 	if (!(R_TAC & 0x04)) return;
 
 	unit = ((-R_TAC) & 3) << 1;
-	cpu.tim += (cnt<<unit);
+	cpu->tim += (cnt<<unit);
 
-	if (cpu.tim >= 512)
+	if (cpu->tim >= 512)
 	{
-		tima = R_TIMA + (cpu.tim >> 9);
-		cpu.tim &= 0x1ff;
+		tima = R_TIMA + (cpu->tim >> 9);
+		cpu->tim &= 0x1ff;
 		if (tima >= 256)
 		{
 			hw_interrupt(IF_TIMER, IF_TIMER);
@@ -325,21 +319,21 @@ void timer_advance(int cnt)
 */
 inline void lcdc_advance(int cnt)
 {
-	cpu.lcdc -= cnt;
-	if (cpu.lcdc <= 0) lcdc_trans();
+	cpu->lcdc -= cnt;
+	if (cpu->lcdc <= 0) lcdc_trans();
 }
 
 /* cnt - time to emulate, expressed in 2MHz units */
 inline void sound_advance(int cnt)
 {
-	cpu.snd += cnt;
+	cpu->snd += cnt;
 }
 
 /* cnt - time to emulate, expressed in 2MHz units */
 void cpu_timers(int cnt)
 {
-	div_advance(cnt << cpu.speed);
-	timer_advance(cnt << cpu.speed);
+	div_advance(cnt << cpu->speed);
+	timer_advance(cnt << cpu->speed);
 	lcdc_advance(cnt);
 	sound_advance(cnt);
 }
@@ -356,16 +350,16 @@ int cpu_idle(int max)
 	int cnt, unit;
 
 
-	if (!(cpu.halt && IME)) return 0;
+	if (!(cpu->halt && IME)) return 0;
 	if (R_IF & R_IE)
 	{
-		cpu.halt = 0;
+		cpu->halt = 0;
 		return 0;
 	}
 
 	/* Make sure we don't miss lcdc status events! */
-	if ((R_IE & (IF_VBLANK | IF_STAT)) && (max > cpu.lcdc))
-		max = cpu.lcdc;
+	if ((R_IE & (IF_VBLANK | IF_STAT)) && (max > cpu->lcdc))
+		max = cpu->lcdc;
 
 	/* If timer interrupt cannot happen, this is very simple! */
 	if (!((R_IE & IF_TIMER) && (R_TAC & 0x04)))
@@ -376,7 +370,7 @@ int cpu_idle(int max)
 
 	/* Figure out when the next timer interrupt will happen */
 	unit = ((-R_TAC) & 3) << 1;
-	cnt = (511 - cpu.tim + (1<<unit)) >> unit;
+	cnt = (511 - cpu->tim + (1<<unit)) >> unit;
 	cnt += (255 - R_TIMA) << (9 - unit);
 
 	if (max < cnt)
@@ -909,15 +903,15 @@ int cpu_emulate(int cycles)
 		PC++;
 		if (R_KEY1 & 1)
 		{
-			cpu.speed = cpu.speed ^ 1;
-			R_KEY1 = (R_KEY1 & 0x7E) | (cpu.speed << 7);
+			cpu->speed = cpu->speed ^ 1;
+			R_KEY1 = (R_KEY1 & 0x7E) | (cpu->speed << 7);
 			break;
 		}
 		/* NOTE - we do not implement dmg STOP whatsoever */
 		break;
 
 	case 0x76: /* HALT */
-		cpu.halt = 1;
+		cpu->halt = 1;
 		break;
 
 	case 0xCB: /* CB prefix */
@@ -956,7 +950,7 @@ int cpu_emulate(int cycles)
 	clen <<= 1;
 	div_advance(clen);
 	timer_advance(clen);
-	clen >>= cpu.speed;
+	clen >>= cpu->speed;
 	lcdc_advance(clen);
 	sound_advance(clen);
 

components/gbc/gnuboy/src/emu.c

@@ -41,7 +41,7 @@ void emu_reset()
 */
 void emu_step()
 {
-	cpu_emulate(cpu.lcdc);
+	cpu_emulate(cpu->lcdc);
 }
 
 

components/gbc/gnuboy/src/hw.c

@@ -31,9 +31,9 @@ void hw_interrupt(byte i, byte mask)
 	R_IF |= i & (hw.ilines ^ i);
 
 	/* FIXME - is this correct? not sure the docs understand... */
-	if ((R_IF & (R_IF ^ oldif) & R_IE) && cpu.ime) cpu.halt = 0;
-	/* if ((i & (hw.ilines ^ i) & R_IE) && cpu.ime) cpu.halt = 0; */
-	/* if ((i & R_IE) && cpu.ime) cpu.halt = 0; */
+	if ((R_IF & (R_IF ^ oldif) & R_IE) && cpu->ime) cpu->halt = 0;
+	/* if ((i & (hw.ilines ^ i) & R_IE) && cpu->ime) cpu->halt = 0; */
+	/* if ((i & R_IE) && cpu->ime) cpu->halt = 0; */
 
 	hw.ilines &= ~mask;
 	hw.ilines |= i;