Merge pull request #114 from davidgfnet/master

Adding Normmatt's BIOS as a built-in BIOS

9 files changed, 147 insertions, 25 deletions

diff --git a/Makefile.common b/Makefile.common
index 7e70627..0dcbedc 100644
--- a/Makefile.common
+++ b/Makefile.common
@@ -1,6 +1,6 @@
 INCFLAGS   := -I$(CORE_DIR)/libretro -I$(CORE_DIR)/src
 
-SOURCES_ASM :=
+SOURCES_ASM := $(CORE_DIR)/bios_data.S
 
 ifeq ($(HAVE_GRIFFIN), 1)
 SOURCES_C := $(CORE_DIR)/gpsp_griffin.c
diff --git a/bios/README.md b/bios/README.md
new file mode 100644
index 0000000..64d6679
--- /dev/null
+++ b/bios/README.md
@@ -0,0 +1,7 @@
+
+This BIOS is an open source replacement for Nintendo's official BIOS.
+It was written originally by Normmatt and the VBA/VBA-M team, and its source
+code can be found at https://github.com/Nebuleon/ReGBA/tree/master/bios
+
+It is distributed under the GPL2 license (see repo)
+
diff --git a/bios/open_gba_bios.bin b/bios/open_gba_bios.bin
new file mode 100644
index 0000000..802982e
--- /dev/null
+++ b/bios/open_gba_bios.bin
diff --git a/bios_data.S b/bios_data.S
new file mode 100644
index 0000000..9de9d8a
--- /dev/null
+++ b/bios_data.S
@@ -0,0 +1,7 @@
+
+.globl open_gba_bios_rom
+
+.data
+open_gba_bios_rom:
+  .incbin "bios/open_gba_bios.bin"
+
diff --git a/cpu.c b/cpu.c
index 2c93f38..11c947f 100644
--- a/cpu.c
+++ b/cpu.c
@@ -4297,13 +4297,23 @@ void init_cpu(void)
   for(i = 0; i < 16; i++)
     reg[i] = 0;
 
-  reg[REG_SP] = 0x03007F00;
-  reg[REG_PC] = 0x08000000;
-  reg[REG_CPSR] = 0x0000001F;
   reg[CPU_HALT_STATE] = CPU_ACTIVE;
-  reg[CPU_MODE] = MODE_USER;
   reg[CHANGED_PC_STATUS] = 0;
 
+  if (selected_boot_mode == boot_game) {
+    reg[REG_SP] = 0x03007F00;
+    reg[REG_PC] = 0x08000000;
+    reg[REG_CPSR] = 0x0000001F;   // system mode
+    reg[CPU_MODE] = MODE_USER;
+  } else {
+    reg[REG_SP] = 0x03007F00;
+    reg[REG_PC] = 0x00000000;
+    reg[REG_CPSR] = 0x00000013 | 0xC0;  // supervisor
+    reg[CPU_MODE] = MODE_SUPERVISOR;
+  }
+
+  // Stack pointers are set by BIOS, we set them
+  // nevertheless, should we not boot from BIOS
   reg_mode[MODE_USER][5] = 0x03007F00;
   reg_mode[MODE_IRQ][5] = 0x03007FA0;
   reg_mode[MODE_FIQ][5] = 0x03007FA0;
diff --git a/gba_memory.h b/gba_memory.h
index 9352e88..eaa5bab 100644
--- a/gba_memory.h
+++ b/gba_memory.h
@@ -201,6 +201,7 @@ extern u32 gbc_sound_update;
 extern u32 gbc_sound_wave_update;
 extern dma_transfer_type dma[4];
 
+extern u8 open_gba_bios_rom[1024*16];
 extern u32 bios_read_protect;
 extern u16 palette_ram[512];
 extern u16 oam_ram[512];
diff --git a/libretro.c b/libretro.c
index bc61977..334864c 100644
--- a/libretro.c
+++ b/libretro.c
@@ -65,6 +65,7 @@ static unsigned audio_buff_occupancy         = 0;
 static bool audio_buff_underrun              = false;
 static unsigned audio_latency                = 0;
 static bool update_audio_latency             = false;
+static bios_type selected_bios               = auto_detect;
 
 static retro_log_printf_t log_cb;
 static retro_video_refresh_t video_cb;
@@ -75,6 +76,7 @@ struct retro_perf_callback perf_cb;
 
 int dynarec_enable;
 int use_libretro_save_method = 0;
+boot_mode selected_boot_mode = boot_game;
 
 u32 idle_loop_target_pc = 0xFFFFFFFF;
 u32 iwram_stack_optimize = 1;
@@ -114,6 +116,25 @@ static void info_msg(const char* text)
       log_cb(RETRO_LOG_INFO, "[gpSP]: %s\n", text);
 }
 
+static void show_warning_message(const char* text, unsigned durationms) {
+  unsigned ifversion = 0;
+  if (!environ_cb(RETRO_ENVIRONMENT_GET_MESSAGE_INTERFACE_VERSION, &ifversion) || ifversion >= 1) {
+    /* Use the new API to display messages */
+    struct retro_message_ext msg = {
+      .msg = text, .duration = durationms,
+      .priority = 2, .level = RETRO_LOG_WARN,
+      .target = RETRO_MESSAGE_TARGET_ALL,
+      .type = RETRO_MESSAGE_TYPE_NOTIFICATION,
+      .progress = -1,
+    };
+    environ_cb(RETRO_ENVIRONMENT_SET_MESSAGE_EXT, &msg);
+  }
+  else {
+    struct retro_message msg = {.msg = text, .frames = durationms / 17};
+    environ_cb(RETRO_ENVIRONMENT_SET_MESSAGE, &msg);
+  }
+}
+
 /* Frameskip START */
 
 static void audio_buff_status_cb(
@@ -348,8 +369,8 @@ static void video_run(void)
    sceGuTexMode(GU_PSM_5650, 0, 0, GU_FALSE);
    sceGuCopyImage(GU_PSM_5650, 0, 0, GBA_SCREEN_WIDTH, GBA_SCREEN_HEIGHT, GBA_SCREEN_WIDTH,
                gba_screen_pixels_buf, 0, 0, GBA_SCREEN_WIDTH, texture_vram_p);
-	sceGuTexImage(0, next_pow2(GBA_SCREEN_WIDTH), next_pow2(GBA_SCREEN_HEIGHT), GBA_SCREEN_WIDTH, texture_vram_p);
-	sceGuTexFunc(GU_TFX_REPLACE, GU_TCC_RGB);
+   sceGuTexImage(0, next_pow2(GBA_SCREEN_WIDTH), next_pow2(GBA_SCREEN_HEIGHT), GBA_SCREEN_WIDTH, texture_vram_p);
+   sceGuTexFunc(GU_TFX_REPLACE, GU_TCC_RGB);
    sceGuDisable(GU_BLEND);
 
    sceGuFinish();
@@ -484,6 +505,8 @@ void retro_init(void)
    audio_buff_underrun    = false;
    audio_latency          = 0;
    update_audio_latency   = false;
+   selected_bios          = auto_detect;
+   selected_boot_mode     = boot_game;
 }
 
 void retro_deinit(void)
@@ -660,6 +683,32 @@ static void check_variables(int started_from_load)
    dynarec_enable = 0;
 #endif
 
+   if (started_from_load) {
+     var.key                = "gpsp_bios";
+     var.value              = 0;
+
+     if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value)
+     {
+        if (!strcmp(var.value, "auto"))
+           selected_bios = auto_detect;
+        else if (!strcmp(var.value, "builtin"))
+           selected_bios = builtin_bios;
+        else if (!strcmp(var.value, "official"))
+           selected_bios = official_bios;
+     }
+
+     var.key                = "gpsp_boot_mode";
+     var.value              = 0;
+
+     if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value)
+     {
+        if (!strcmp(var.value, "game"))
+           selected_boot_mode = boot_game;
+        else if (!strcmp(var.value, "bios"))
+           selected_boot_mode = boot_bios;
+     }
+   }
+
    var.key                = "gpsp_frameskip";
    var.value              = 0;
    frameskip_type_prev    = current_frameskip_type;
@@ -795,30 +844,41 @@ bool retro_load_game(const struct retro_game_info* info)
 
    extract_directory(main_path, info->path, sizeof(main_path));
 
-   if (environ_cb(RETRO_ENVIRONMENT_GET_SYSTEM_DIRECTORY, &dir) && dir)
-      strcpy(filename_bios, dir);
-   else
-      strcpy(filename_bios, main_path);
-
-   strcat(filename_bios, "/gba_bios.bin");
-
-
    if (environ_cb(RETRO_ENVIRONMENT_GET_SAVE_DIRECTORY, &dir) && dir)
       strcpy(save_path, dir);
    else
       strcpy(save_path, main_path);
 
-   if (load_bios(filename_bios) != 0)
+   if (environ_cb(RETRO_ENVIRONMENT_GET_SYSTEM_DIRECTORY, &dir) && dir)
+      strcpy(filename_bios, dir);
+   else
+      strcpy(filename_bios, main_path);
+
+   bool bios_loaded = false;
+   printf("USE %d\n", (int)selected_bios);
+   if (selected_bios == auto_detect || selected_bios == official_bios)
    {
-      error_msg("Could not load BIOS image file.");
-      return false;
+     bios_loaded = true;
+     strcat(filename_bios, "/gba_bios.bin");
+
+     if (load_bios(filename_bios) != 0)
+     {
+        if (selected_bios == official_bios)
+          show_warning_message("Could not load BIOS image file, using built-in BIOS", 2500);
+        bios_loaded = false;
+     }
+
+     if (bios_loaded && bios_rom[0] != 0x18)
+     {
+        if (selected_bios == official_bios)
+          show_warning_message("BIOS image seems incorrect, using built-in BIOS", 2500);
+        bios_loaded = false;
+     }
    }
 
-   if (bios_rom[0] != 0x18)
-   {
-      info_msg("You have an incorrect BIOS image.");
-      info_msg("While many games will work fine, some will not.");
-      info_msg("It is strongly recommended that you obtain the correct BIOS file.");
+   if (!bios_loaded) {
+     /* Load the built-in BIOS */
+     memcpy(bios_rom, open_gba_bios_rom, sizeof(bios_rom));
    }
 
    memset(gamepak_backup, -1, sizeof(gamepak_backup));
@@ -921,8 +981,8 @@ void retro_run(void)
 
    input_poll_cb();
 
-	/* Check whether current frame should
-	 * be skipped */
+   /* Check whether current frame should
+    * be skipped */
    skip_next_frame = 0;
 
    if (current_frameskip_type != no_frameskip)
diff --git a/libretro_core_options.h b/libretro_core_options.h
index b5b138d..d2b95fa 100644
--- a/libretro_core_options.h
+++ b/libretro_core_options.h
@@ -54,6 +54,29 @@ extern "C" {
 
 struct retro_core_option_definition option_defs_us[] = {
    {
+      "gpsp_bios",
+      "BIOS",
+      "Choose the BIOS image to use. The official BIOS must be provided by the user. Using a non-official (or builtin) BIOS might result in incompatibility problems with some games. Best results are to be achieved with the official Nintendo BIOS.",
+      {
+         { "auto",      "Auto select" },
+         { "builtin",   "Builtin BIOS" },
+         { "official",  "Original BIOS" },
+         { NULL, NULL },
+      },
+      "auto"
+   },
+   {
+      "gpsp_boot_mode",
+      "Boot mode",
+      "Choose whether to boot the BIOS before the game or not. There's not much difference in either modes.",
+      {
+         { "game",      "Boot to game" },
+         { "bios",      "Boot to BIOS" },
+         { NULL, NULL },
+      },
+      "game"
+   },
+   {
       "gpsp_frameskip",
       "Frameskip",
       "Skip frames to avoid audio buffer under-run (crackling). Improves performance at the expense of visual smoothness. 'Auto' skips frames when advised by the frontend. 'Auto (Threshold)' utilises the 'Frameskip Threshold (%)' setting. 'Fixed Interval' utilises the 'Frameskip Interval' setting.",
diff --git a/main.h b/main.h
index dbb839f..bdb29e3 100644
--- a/main.h
+++ b/main.h
@@ -64,6 +64,19 @@ typedef enum
   fixed_interval_frameskip
 } frameskip_type;
 
+typedef enum
+{
+  auto_detect = 0,
+  builtin_bios,
+  official_bios
+} bios_type;
+
+typedef enum
+{
+  boot_game = 0,
+  boot_bios
+} boot_mode;
+
 extern u32 cpu_ticks;
 extern u32 execute_cycles;
 extern u32 global_cycles_per_instruction;
@@ -98,6 +111,7 @@ u32 file_length(FILE *fp);
 
 extern u32 num_skipped_frames;
 extern int dynarec_enable;
+extern boot_mode selected_boot_mode;
 
 void change_ext(const char *src, char *buffer, const char *extension);