[picodrive.git] / platform / libretro / libretro.c

/*
 * libretro core glue for PicoDrive
 * (C) notaz, 2013
 *
 * This work is licensed under the terms of MAME license.
 * See COPYING file in the top-level directory.
 */

#define _GNU_SOURCE 1 // mremap
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#ifndef _WIN32
#ifndef NO_MMAP
#include <sys/mman.h>
#endif
#else
#include <io.h>
#include <windows.h>
#include <sys/types.h>
#endif
#include <errno.h>
#ifdef __MACH__
#include <libkern/OSCacheControl.h>
#endif

#include <pico/pico_int.h>
#include <pico/state.h>
#include "../common/input_pico.h"
#include "../common/version.h"
#include "libretro.h"

static retro_log_printf_t log_cb;
static retro_video_refresh_t video_cb;
static retro_input_poll_t input_poll_cb;
static retro_input_state_t input_state_cb;
static retro_environment_t environ_cb;
static retro_audio_sample_batch_t audio_batch_cb;

#define VOUT_MAX_WIDTH 320
#define VOUT_MAX_HEIGHT 240
static void *vout_buf;
static int vout_width, vout_height, vout_offset;

static short __attribute__((aligned(4))) sndBuffer[2*44100/50];

static void snd_write(int len);

#ifdef _WIN32
#define SLASH '\\'
#else
#define SLASH '/'
#endif

/* functions called by the core */

void cache_flush_d_inval_i(void *start, void *end)
{
#ifdef __arm__
#if defined(__BLACKBERRY_QNX__)
	msync(start, end - start, MS_SYNC | MS_CACHE_ONLY | MS_INVALIDATE_ICACHE);
#elif defined(__MACH__)
	size_t len = (char *)end - (char *)start;
	sys_dcache_flush(start, len);
	sys_icache_invalidate(start, len);
#else
	__clear_cache(start, end);
#endif
#endif
}

#ifdef _WIN32
/* mmap() replacement for Windows
 *
 * Author: Mike Frysinger <vapier@gentoo.org>
 * Placed into the public domain
 */

/* References:
 * CreateFileMapping: http://msdn.microsoft.com/en-us/library/aa366537(VS.85).aspx
 * CloseHandle:       http://msdn.microsoft.com/en-us/library/ms724211(VS.85).aspx
 * MapViewOfFile:     http://msdn.microsoft.com/en-us/library/aa366761(VS.85).aspx
 * UnmapViewOfFile:   http://msdn.microsoft.com/en-us/library/aa366882(VS.85).aspx
 */

#define PROT_READ     0x1
#define PROT_WRITE    0x2
/* This flag is only available in WinXP+ */
#ifdef FILE_MAP_EXECUTE
#define PROT_EXEC     0x4
#else
#define PROT_EXEC        0x0
#define FILE_MAP_EXECUTE 0
#endif

#define MAP_SHARED    0x01
#define MAP_PRIVATE   0x02
#define MAP_ANONYMOUS 0x20
#define MAP_ANON      MAP_ANONYMOUS
#define MAP_FAILED    ((void *) -1)

#ifdef __USE_FILE_OFFSET64
# define DWORD_HI(x) (x >> 32)
# define DWORD_LO(x) ((x) & 0xffffffff)
#else
# define DWORD_HI(x) (0)
# define DWORD_LO(x) (x)
#endif

static void *mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset)
{
	if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC))
		return MAP_FAILED;
	if (fd == -1) {
		if (!(flags & MAP_ANON) || offset)
			return MAP_FAILED;
	} else if (flags & MAP_ANON)
		return MAP_FAILED;

	DWORD flProtect;
	if (prot & PROT_WRITE) {
		if (prot & PROT_EXEC)
			flProtect = PAGE_EXECUTE_READWRITE;
		else
			flProtect = PAGE_READWRITE;
	} else if (prot & PROT_EXEC) {
		if (prot & PROT_READ)
			flProtect = PAGE_EXECUTE_READ;
		else if (prot & PROT_EXEC)
			flProtect = PAGE_EXECUTE;
	} else
		flProtect = PAGE_READONLY;

	off_t end = length + offset;
	HANDLE mmap_fd, h;
	if (fd == -1)
		mmap_fd = INVALID_HANDLE_VALUE;
	else
		mmap_fd = (HANDLE)_get_osfhandle(fd);
	h = CreateFileMapping(mmap_fd, NULL, flProtect, DWORD_HI(end), DWORD_LO(end), NULL);
	if (h == NULL)
		return MAP_FAILED;

	DWORD dwDesiredAccess;
	if (prot & PROT_WRITE)
		dwDesiredAccess = FILE_MAP_WRITE;
	else
		dwDesiredAccess = FILE_MAP_READ;
	if (prot & PROT_EXEC)
		dwDesiredAccess |= FILE_MAP_EXECUTE;
	if (flags & MAP_PRIVATE)
		dwDesiredAccess |= FILE_MAP_COPY;
	void *ret = MapViewOfFile(h, dwDesiredAccess, DWORD_HI(offset), DWORD_LO(offset), length);
	if (ret == NULL) {
		CloseHandle(h);
		ret = MAP_FAILED;
	}
	return ret;
}

static void munmap(void *addr, size_t length)
{
	UnmapViewOfFile(addr);
	/* ruh-ro, we leaked handle from CreateFileMapping() ... */
}
#elif defined(NO_MMAP)
#define PROT_EXEC   0x04
#define MAP_FAILED 0
#define PROT_READ 0
#define PROT_WRITE 0
#define MAP_PRIVATE 0
#define MAP_ANONYMOUS 0

void* mmap(void *desired_addr, size_t len, int mmap_prot, int mmap_flags, int fildes, size_t off)
{
   return malloc(len);
}

void munmap(void *base_addr, size_t len)
{
   free(base_addr);
}

int mprotect(void *addr, size_t len, int prot)
{
   /* stub - not really needed at this point since this codepath has no dynarecs */
   return 0;
}

#endif

#ifndef MAP_ANONYMOUS
#define MAP_ANONYMOUS MAP_ANON
#endif

void *plat_mmap(unsigned long addr, size_t size, int need_exec, int is_fixed)
{
   int flags = MAP_PRIVATE | MAP_ANONYMOUS;
   void *req, *ret;

   req = (void *)addr;
   ret = mmap(req, size, PROT_READ | PROT_WRITE, flags, -1, 0);
   if (ret == MAP_FAILED) {
      if (log_cb)
         log_cb(RETRO_LOG_ERROR, "mmap(%08lx, %zd) failed: %d\n", addr, size, errno);
      return NULL;
   }

   if (addr != 0 && ret != (void *)addr) {
      if (log_cb)
         log_cb(RETRO_LOG_WARN, "warning: wanted to map @%08lx, got %p\n",
               addr, ret);

      if (is_fixed) {
         munmap(ret, size);
         return NULL;
      }
   }

	return ret;
}

void *plat_mremap(void *ptr, size_t oldsize, size_t newsize)
{
#ifdef __linux__
	void *ret = mremap(ptr, oldsize, newsize, 0);
	if (ret == MAP_FAILED)
		return NULL;

	return ret;
#else
	void *tmp, *ret;
	size_t preserve_size;
	
	preserve_size = oldsize;
	if (preserve_size > newsize)
		preserve_size = newsize;
	tmp = malloc(preserve_size);
	if (tmp == NULL)
		return NULL;
	memcpy(tmp, ptr, preserve_size);

	munmap(ptr, oldsize);
	ret = mmap(ptr, newsize, PROT_READ | PROT_WRITE,
		   MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
	if (ret == MAP_FAILED) {
		free(tmp);
		return NULL;
	}
	memcpy(ret, tmp, preserve_size);
	free(tmp);
	return ret;
#endif
}

void plat_munmap(void *ptr, size_t size)
{
	if (ptr != NULL)
		munmap(ptr, size);
}

int plat_mem_set_exec(void *ptr, size_t size)
{
#ifdef _WIN32
   int ret = VirtualProtect(ptr,size,PAGE_EXECUTE_READWRITE,0);
   if (ret == 0 && log_cb)
      log_cb(RETRO_LOG_ERROR, "mprotect(%p, %zd) failed: %d\n", ptr, size, 0);
#else
   int ret = mprotect(ptr, size, PROT_READ | PROT_WRITE | PROT_EXEC);
   if (ret != 0 && log_cb)
      log_cb(RETRO_LOG_ERROR, "mprotect(%p, %zd) failed: %d\n", ptr, size, errno);
#endif
	return ret;
}

void emu_video_mode_change(int start_line, int line_count, int is_32cols)
{
	memset(vout_buf, 0, 320 * 240 * 2);
	vout_width = is_32cols ? 256 : 320;
	PicoDrawSetOutBuf(vout_buf, vout_width * 2);

	vout_height = line_count;
	vout_offset = vout_width * start_line;
}

void emu_32x_startup(void)
{
}

void lprintf(const char *fmt, ...)
{
   char buffer[256];
   va_list ap;
   va_start(ap, fmt);
   vsprintf(buffer, fmt, ap);
   /* TODO - add 'level' param for warning/error messages? */
   if (log_cb)
      log_cb(RETRO_LOG_INFO, "%s\n", fmt);
}

/* libretro */
void retro_set_environment(retro_environment_t cb)
{
	static const struct retro_variable vars[] = {
		//{ "region", "Region; Auto|NTSC|PAL" },
		{ "picodrive_input1", "Input device 1; 3 button pad|6 button pad|None" },
		{ "picodrive_input2", "Input device 2; 3 button pad|6 button pad|None" },
		{ "picodrive_sprlim", "No sprite limit; disabled|enabled" },
		{ "picodrive_ramcart", "MegaCD RAM cart; disabled|enabled" },
#ifdef DRC_SH2
		{ "picodrive_drc", "Dynamic recompilers; enabled|disabled" },
#endif
		{ NULL, NULL },
	};

	environ_cb = cb;

	cb(RETRO_ENVIRONMENT_SET_VARIABLES, (void *)vars);
}

void retro_set_video_refresh(retro_video_refresh_t cb) { video_cb = cb; }
void retro_set_audio_sample(retro_audio_sample_t cb) { (void)cb; }
void retro_set_audio_sample_batch(retro_audio_sample_batch_t cb) { audio_batch_cb = cb; }
void retro_set_input_poll(retro_input_poll_t cb) { input_poll_cb = cb; }
void retro_set_input_state(retro_input_state_t cb) { input_state_cb = cb; }

unsigned retro_api_version(void)
{
	return RETRO_API_VERSION;
}

void retro_set_controller_port_device(unsigned port, unsigned device)
{
}

void retro_get_system_info(struct retro_system_info *info)
{
	memset(info, 0, sizeof(*info));
	info->library_name = "PicoDrive";
	info->library_version = VERSION;
	info->valid_extensions = "bin|gen|smd|md|32x|cue|iso|sms";
	info->need_fullpath = true;
}

void retro_get_system_av_info(struct retro_system_av_info *info)
{
	memset(info, 0, sizeof(*info));
	info->timing.fps            = Pico.m.pal ? 50 : 60;
	info->timing.sample_rate    = 44100;
	info->geometry.base_width   = 320;
	info->geometry.base_height  = vout_height;
	info->geometry.max_width    = VOUT_MAX_WIDTH;
	info->geometry.max_height   = VOUT_MAX_HEIGHT;
	info->geometry.aspect_ratio = 0.0f;
}

/* savestates */
struct savestate_state {
	const char *load_buf;
	char *save_buf;
	size_t size;
	size_t pos;
};

size_t state_read(void *p, size_t size, size_t nmemb, void *file)
{
	struct savestate_state *state = file;
	size_t bsize = size * nmemb;

	if (state->pos + bsize > state->size) {
      if (log_cb)
         log_cb(RETRO_LOG_ERROR, "savestate error: %u/%u\n",
               state->pos + bsize, state->size);
		bsize = state->size - state->pos;
		if ((int)bsize <= 0)
			return 0;
	}

	memcpy(p, state->load_buf + state->pos, bsize);
	state->pos += bsize;
	return bsize;
}

size_t state_write(void *p, size_t size, size_t nmemb, void *file)
{
	struct savestate_state *state = file;
	size_t bsize = size * nmemb;

	if (state->pos + bsize > state->size) {
      if (log_cb)
         log_cb(RETRO_LOG_ERROR, "savestate error: %u/%u\n",
               state->pos + bsize, state->size);
		bsize = state->size - state->pos;
		if ((int)bsize <= 0)
			return 0;
	}

	memcpy(state->save_buf + state->pos, p, bsize);
	state->pos += bsize;
	return bsize;
}

size_t state_skip(void *p, size_t size, size_t nmemb, void *file)
{
	struct savestate_state *state = file;
	size_t bsize = size * nmemb;

	state->pos += bsize;
	return bsize;
}

size_t state_eof(void *file)
{
	struct savestate_state *state = file;

	return state->pos >= state->size;
}

int state_fseek(void *file, long offset, int whence)
{
	struct savestate_state *state = file;

	switch (whence) {
	case SEEK_SET:
		state->pos = offset;
		break;
	case SEEK_CUR:
		state->pos += offset;
		break;
	case SEEK_END:
		state->pos = state->size + offset;
		break;
	}
	return (int)state->pos;
}

/* savestate sizes vary wildly depending if cd/32x or
 * carthw is active, so run the whole thing to get size */
size_t retro_serialize_size(void) 
{ 
	struct savestate_state state = { 0, };
	int ret;

	ret = PicoStateFP(&state, 1, NULL, state_skip, NULL, state_fseek);
	if (ret != 0)
		return 0;

	return state.pos;
}

bool retro_serialize(void *data, size_t size)
{ 
	struct savestate_state state = { 0, };
	int ret;

	state.save_buf = data;
	state.size = size;
	state.pos = 0;

	ret = PicoStateFP(&state, 1, NULL, state_write,
		NULL, state_fseek);
	return ret == 0;
}

bool retro_unserialize(const void *data, size_t size)
{
	struct savestate_state state = { 0, };
	int ret;

	state.load_buf = data;
	state.size = size;
	state.pos = 0;

	ret = PicoStateFP(&state, 0, state_read, NULL,
		state_eof, state_fseek);
	return ret == 0;
}

/* cheats - TODO */
void retro_cheat_reset(void)
{
}

void retro_cheat_set(unsigned index, bool enabled, const char *code)
{
}

/* multidisk support */
static bool disk_ejected;
static unsigned int disk_current_index;
static unsigned int disk_count;
static struct disks_state {
	char *fname;
} disks[8];

static bool disk_set_eject_state(bool ejected)
{
	// TODO?
	disk_ejected = ejected;
	return true;
}

static bool disk_get_eject_state(void)
{
	return disk_ejected;
}

static unsigned int disk_get_image_index(void)
{
	return disk_current_index;
}

static bool disk_set_image_index(unsigned int index)
{
	enum cd_img_type cd_type;
	int ret;

	if (index >= sizeof(disks) / sizeof(disks[0]))
		return false;

	if (disks[index].fname == NULL) {
      if (log_cb)
         log_cb(RETRO_LOG_ERROR, "missing disk #%u\n", index);

		// RetroArch specifies "no disk" with index == count,
		// so don't fail here..
		disk_current_index = index;
		return true;
	}

   if (log_cb)
      log_cb(RETRO_LOG_INFO, "switching to disk %u: \"%s\"\n", index,
            disks[index].fname);

	ret = -1;
	cd_type = PicoCdCheck(disks[index].fname, NULL);
	if (cd_type != CIT_NOT_CD)
		ret = cdd_load(disks[index].fname, cd_type);
	if (ret != 0) {
      if (log_cb)
         log_cb(RETRO_LOG_ERROR, "Load failed, invalid CD image?\n");
		return 0;
	}

	disk_current_index = index;
	return true;
}

static unsigned int disk_get_num_images(void)
{
	return disk_count;
}

static bool disk_replace_image_index(unsigned index,
	const struct retro_game_info *info)
{
	bool ret = true;

	if (index >= sizeof(disks) / sizeof(disks[0]))
		return false;

	if (disks[index].fname != NULL)
		free(disks[index].fname);
	disks[index].fname = NULL;

	if (info != NULL) {
		disks[index].fname = strdup(info->path);
		if (index == disk_current_index)
			ret = disk_set_image_index(index);
	}

	return ret;
}

static bool disk_add_image_index(void)
{
	if (disk_count >= sizeof(disks) / sizeof(disks[0]))
		return false;

	disk_count++;
	return true;
}

static struct retro_disk_control_callback disk_control = {
	.set_eject_state = disk_set_eject_state,
	.get_eject_state = disk_get_eject_state,
	.get_image_index = disk_get_image_index,
	.set_image_index = disk_set_image_index,
	.get_num_images = disk_get_num_images,
	.replace_image_index = disk_replace_image_index,
	.add_image_index = disk_add_image_index,
};

static void disk_tray_open(void)
{
   if (log_cb)
      log_cb(RETRO_LOG_INFO, "cd tray open\n");
	disk_ejected = 1;
}

static void disk_tray_close(void)
{
   if (log_cb)
      log_cb(RETRO_LOG_INFO, "cd tray close\n");
	disk_ejected = 0;
}


static const char * const biosfiles_us[] = {
	"us_scd2_9306", "SegaCDBIOS9303", "us_scd1_9210", "bios_CD_U"
};
static const char * const biosfiles_eu[] = {
	"eu_mcd2_9306", "eu_mcd2_9303", "eu_mcd1_9210", "bios_CD_E"
};
static const char * const biosfiles_jp[] = {
	"jp_mcd2_921222", "jp_mcd1_9112", "jp_mcd1_9111", "bios_CD_J"
};

static void make_system_path(char *buf, size_t buf_size,
	const char *name, const char *ext)
{
	const char *dir = NULL;

	if (environ_cb(RETRO_ENVIRONMENT_GET_SYSTEM_DIRECTORY, &dir) && dir) {
		snprintf(buf, buf_size, "%s%c%s%s", dir, SLASH, name, ext);
	}
	else {
		snprintf(buf, buf_size, "%s%s", name, ext);
	}
}

static const char *find_bios(int *region, const char *cd_fname)
{
	const char * const *files;
	static char path[256];
	int i, count;
	FILE *f = NULL;

	if (*region == 4) { // US
		files = biosfiles_us;
		count = sizeof(biosfiles_us) / sizeof(char *);
	} else if (*region == 8) { // EU
		files = biosfiles_eu;
		count = sizeof(biosfiles_eu) / sizeof(char *);
	} else if (*region == 1 || *region == 2) {
		files = biosfiles_jp;
		count = sizeof(biosfiles_jp) / sizeof(char *);
	} else {
		return NULL;
	}

	for (i = 0; i < count; i++)
	{
		make_system_path(path, sizeof(path), files[i], ".bin");
		f = fopen(path, "rb");
		if (f != NULL)
			break;

		make_system_path(path, sizeof(path), files[i], ".zip");
		f = fopen(path, "rb");
		if (f != NULL)
			break;
	}

	if (f != NULL) {
      if (log_cb)
         log_cb(RETRO_LOG_INFO, "using bios: %s\n", path);
		fclose(f);
		return path;
	}

	return NULL;
}

bool retro_load_game(const struct retro_game_info *info)
{
	enum media_type_e media_type;
	static char carthw_path[256];
	size_t i;

	enum retro_pixel_format fmt = RETRO_PIXEL_FORMAT_RGB565;
	if (!environ_cb(RETRO_ENVIRONMENT_SET_PIXEL_FORMAT, &fmt)) {
      if (log_cb)
         log_cb(RETRO_LOG_ERROR, "RGB565 support required, sorry\n");
		return false;
	}

	if (info == NULL || info->path == NULL) {
      if (log_cb)
         log_cb(RETRO_LOG_ERROR, "info->path required\n");
		return false;
	}

	for (i = 0; i < sizeof(disks) / sizeof(disks[0]); i++) {
		if (disks[i].fname != NULL) {
			free(disks[i].fname);
			disks[i].fname = NULL;
		}
	}

	disk_current_index = 0;
	disk_count = 1;
	disks[0].fname = strdup(info->path);

	make_system_path(carthw_path, sizeof(carthw_path), "carthw", ".cfg");

	media_type = PicoLoadMedia(info->path, carthw_path,
			find_bios, NULL);

	switch (media_type) {
	case PM_BAD_DETECT:
      if (log_cb)
         log_cb(RETRO_LOG_ERROR, "Failed to detect ROM/CD image type.\n");
		return false;
	case PM_BAD_CD:
      if (log_cb)
         log_cb(RETRO_LOG_ERROR, "Invalid CD image\n");
		return false;
	case PM_BAD_CD_NO_BIOS:
      if (log_cb)
         log_cb(RETRO_LOG_ERROR, "Missing BIOS\n");
		return false;
	case PM_ERROR:
      if (log_cb)
         log_cb(RETRO_LOG_ERROR, "Load error\n");
		return false;
	default:
		break;
	}

	PicoLoopPrepare();

	PicoWriteSound = snd_write;
	memset(sndBuffer, 0, sizeof(sndBuffer));
	PsndOut = sndBuffer;
	PsndRerate(0);

	return true;
}

bool retro_load_game_special(unsigned game_type, const struct retro_game_info *info, size_t num_info)
{
	return false;
}

void retro_unload_game(void) 
{
}

unsigned retro_get_region(void)
{
	return Pico.m.pal ? RETRO_REGION_PAL : RETRO_REGION_NTSC;
}

void *retro_get_memory_data(unsigned id)
{
	if (id != RETRO_MEMORY_SAVE_RAM)
		return NULL;

	if (PicoAHW & PAHW_MCD)
		return Pico_mcd->bram;
	else
		return SRam.data;
}

size_t retro_get_memory_size(unsigned id)
{
	unsigned int i;
	int sum;

	if (id != RETRO_MEMORY_SAVE_RAM)
		return 0;

	if (PicoAHW & PAHW_MCD)
		// bram
		return 0x2000;

	if (Pico.m.frame_count == 0)
		return SRam.size;

	// if game doesn't write to sram, don't report it to
	// libretro so that RA doesn't write out zeroed .srm
	for (i = 0, sum = 0; i < SRam.size; i++)
		sum |= SRam.data[i];

	return (sum != 0) ? SRam.size : 0;
}

void retro_reset(void)
{
	PicoReset();
}

static const unsigned short retro_pico_map[] = {
	[RETRO_DEVICE_ID_JOYPAD_B]	= 1 << GBTN_B,
	[RETRO_DEVICE_ID_JOYPAD_Y]	= 1 << GBTN_A,
	[RETRO_DEVICE_ID_JOYPAD_SELECT]	= 1 << GBTN_MODE,
	[RETRO_DEVICE_ID_JOYPAD_START]	= 1 << GBTN_START,
	[RETRO_DEVICE_ID_JOYPAD_UP]	= 1 << GBTN_UP,
	[RETRO_DEVICE_ID_JOYPAD_DOWN]	= 1 << GBTN_DOWN,
	[RETRO_DEVICE_ID_JOYPAD_LEFT]	= 1 << GBTN_LEFT,
	[RETRO_DEVICE_ID_JOYPAD_RIGHT]	= 1 << GBTN_RIGHT,
	[RETRO_DEVICE_ID_JOYPAD_A]	= 1 << GBTN_C,
	[RETRO_DEVICE_ID_JOYPAD_X]	= 1 << GBTN_Y,
	[RETRO_DEVICE_ID_JOYPAD_L]	= 1 << GBTN_X,
	[RETRO_DEVICE_ID_JOYPAD_R]	= 1 << GBTN_Z,
};
#define RETRO_PICO_MAP_LEN (sizeof(retro_pico_map) / sizeof(retro_pico_map[0]))

static void snd_write(int len)
{
	audio_batch_cb(PsndOut, len / 4);
}

static enum input_device input_name_to_val(const char *name)
{
	if (strcmp(name, "3 button pad") == 0)
		return PICO_INPUT_PAD_3BTN;
	if (strcmp(name, "6 button pad") == 0)
		return PICO_INPUT_PAD_6BTN;
	if (strcmp(name, "None") == 0)
		return PICO_INPUT_NOTHING;

   if (log_cb)
      log_cb(RETRO_LOG_WARN, "invalid picodrive_input: '%s'\n", name);
	return PICO_INPUT_PAD_3BTN;
}

static void update_variables(void)
{
	struct retro_variable var;

	var.value = NULL;
	var.key = "picodrive_input1";
	if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value)
		PicoSetInputDevice(0, input_name_to_val(var.value));

	var.value = NULL;
	var.key = "picodrive_input2";
	if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value)
		PicoSetInputDevice(1, input_name_to_val(var.value));

	var.value = NULL;
	var.key = "picodrive_sprlim";
	if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value) {
		if (strcmp(var.value, "enabled") == 0)
			PicoOpt |= POPT_DIS_SPRITE_LIM;
		else
			PicoOpt &= ~POPT_DIS_SPRITE_LIM;
	}

	var.value = NULL;
	var.key = "picodrive_ramcart";
	if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value) {
		if (strcmp(var.value, "enabled") == 0)
			PicoOpt |= POPT_EN_MCD_RAMCART;
		else
			PicoOpt &= ~POPT_EN_MCD_RAMCART;
	}

#ifdef DRC_SH2
	var.value = NULL;
	var.key = "picodrive_drc";
	if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value) {
		if (strcmp(var.value, "enabled") == 0)
			PicoOpt |= POPT_EN_DRC;
		else
			PicoOpt &= ~POPT_EN_DRC;
	}
#endif
}

void retro_run(void) 
{
	bool updated = false;
	int pad, i;

	if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE_UPDATE, &updated) && updated)
		update_variables();

	input_poll_cb();

	PicoPad[0] = PicoPad[1] = 0;
	for (pad = 0; pad < 2; pad++)
		for (i = 0; i < RETRO_PICO_MAP_LEN; i++)
			if (input_state_cb(pad, RETRO_DEVICE_JOYPAD, 0, i))
				PicoPad[pad] |= retro_pico_map[i];

	PicoFrame();

	video_cb((short *)vout_buf + vout_offset,
		vout_width, vout_height, vout_width * 2);
}

void retro_init(void)
{
   struct retro_log_callback log;
	int level;

	level = 0;
	environ_cb(RETRO_ENVIRONMENT_SET_PERFORMANCE_LEVEL, &level);

   if (environ_cb(RETRO_ENVIRONMENT_GET_LOG_INTERFACE, &log))
      log_cb = log.log;
   else
      log_cb = NULL;

	environ_cb(RETRO_ENVIRONMENT_SET_DISK_CONTROL_INTERFACE, &disk_control);

	PicoOpt = POPT_EN_STEREO|POPT_EN_FM|POPT_EN_PSG|POPT_EN_Z80
		| POPT_EN_MCD_PCM|POPT_EN_MCD_CDDA|POPT_EN_MCD_GFX
		| POPT_EN_32X|POPT_EN_PWM
		| POPT_ACC_SPRITES|POPT_DIS_32C_BORDER;
#ifdef __arm__
	PicoOpt |= POPT_EN_DRC;
#endif
	PsndRate = 44100;
	PicoAutoRgnOrder = 0x184; // US, EU, JP

	vout_width = 320;
	vout_height = 240;
	vout_buf = malloc(VOUT_MAX_WIDTH * VOUT_MAX_HEIGHT * 2);

	PicoInit();
	PicoDrawSetOutFormat(PDF_RGB555, 0);
	PicoDrawSetOutBuf(vout_buf, vout_width * 2);

	//PicoMessage = plat_status_msg_busy_next;
	PicoMCDopenTray = disk_tray_open;
	PicoMCDcloseTray = disk_tray_close;

	update_variables();
}

void retro_deinit(void)
{
	PicoExit();
}