rockbox/apps/codecs/spc.c
Paul Louden 5fd4c15e2a Fix silly cut an pasting of comments.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@12391 a1c6a512-1295-4272-9138-f99709370657
2007-02-18 09:28:26 +00:00

854 lines
22 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
*
* Copyright (C) 2006-2007 Adam Gashlin (hcs)
* Copyright (C) 2004-2007 Shay Green (blargg)
* Copyright (C) 2002 Brad Martin
*
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
/* lovingly ripped off from Game_Music_Emu 0.5.2. http://www.slack.net/~ant/ */
/* DSP Based on Brad Martin's OpenSPC DSP emulator */
/* tag reading from sexyspc by John Brawn (John_Brawn@yahoo.com) and others */
#include "codeclib.h"
#include "inttypes.h"
#include "system.h"
/* rather than comment out asserts, just define NDEBUG */
#define NDEBUG
#include <assert.h>
#undef check
#define check assert
CODEC_HEADER
#ifdef CPU_ARM
#undef ICODE_ATTR
#define ICODE_ATTR
#undef IDATA_ATTR
#define IDATA_ATTR
#endif
/* TGB is the only target fast enough for gaussian and realtime BRR decode */
/* echo is almost fast enough but not quite */
#ifndef TOSHIBA_GIGABEAT_F
/* Cache BRR waves */
#define SPC_BRRCACHE 1
/* Disable gaussian interpolation */
#define SPC_NOINTERP 1
/* Disable echo processing */
#define SPC_NOECHO 1
#else
/* Don't cache BRR waves */
#define SPC_BRRCACHE 0
/* Allow gaussian interpolation */
#define SPC_NOINTERP 0
/* Allow echo processing */
#define SPC_NOECHO 0
#endif
/* Samples per channel per iteration */
#ifdef CPU_COLDFIRE
#define WAV_CHUNK_SIZE 1024
#else
#define WAV_CHUNK_SIZE 2048
#endif
/* simple profiling with USEC_TIMER */
/*#define SPC_PROFILE*/
#include "spc/spc_profiler.h"
#define THIS struct Spc_Emu* const this
/**************** Little-endian handling ****************/
static inline unsigned get_le16( void const* p )
{
return ((unsigned char const*) p) [1] * 0x100u +
((unsigned char const*) p) [0];
}
static inline int get_le16s( void const* p )
{
return ((signed char const*) p) [1] * 0x100 +
((unsigned char const*) p) [0];
}
static inline void set_le16( void* p, unsigned n )
{
((unsigned char*) p) [1] = (unsigned char) (n >> 8);
((unsigned char*) p) [0] = (unsigned char) n;
}
#define GET_LE16( addr ) get_le16( addr )
#define SET_LE16( addr, data ) set_le16( addr, data )
#ifdef ROCKBOX_LITTLE_ENDIAN
#define GET_LE16A( addr ) (*(uint16_t*) (addr))
#define GET_LE16SA( addr ) (*( int16_t*) (addr))
#define SET_LE16A( addr, data ) (void) (*(uint16_t*) (addr) = (data))
#else
#define GET_LE16A( addr ) get_le16 ( addr )
#define GET_LE16SA( addr ) get_le16s( addr )
#define SET_LE16A( addr, data ) set_le16 ( addr, data )
#endif
static struct
{
union {
uint8_t padding1 [0x100];
uint16_t align;
} padding1 [1];
uint8_t ram [0x10000];
uint8_t padding2 [0x100];
} ram;
#include "spc/Spc_Dsp.h"
#undef RAM
#define RAM ram.ram
/**************** Timers ****************/
enum { timer_count = 3 };
struct Timer
{
long next_tick;
int period;
int count;
int shift;
int enabled;
int counter;
};
static void Timer_run_( struct Timer* t, long time ) ICODE_ATTR;
static void Timer_run_( struct Timer* t, long time )
{
/* when disabled, next_tick should always be in the future */
assert( t->enabled );
int elapsed = ((time - t->next_tick) >> t->shift) + 1;
t->next_tick += elapsed << t->shift;
elapsed += t->count;
if ( elapsed >= t->period ) /* avoid unnecessary division */
{
int n = elapsed / t->period;
elapsed -= n * t->period;
t->counter = (t->counter + n) & 15;
}
t->count = elapsed;
}
static inline void Timer_run( struct Timer* t, long time )
{
if ( time >= t->next_tick )
Timer_run_( t, time );
}
/**************** SPC emulator ****************/
/* 1.024 MHz clock / 32000 samples per second */
enum { clocks_per_sample = 32 };
enum { extra_clocks = clocks_per_sample / 2 };
/* using this disables timer (since this will always be in the future) */
enum { timer_disabled_time = 127 };
enum { rom_size = 64 };
enum { rom_addr = 0xFFC0 };
struct cpu_regs_t
{
long pc; /* more than 16 bits to allow overflow detection */
uint8_t a;
uint8_t x;
uint8_t y;
uint8_t status;
uint8_t sp;
};
struct Spc_Emu
{
uint8_t cycle_table [0x100];
struct cpu_regs_t r;
int32_t* sample_buf;
long next_dsp;
int rom_enabled;
int extra_cycles;
struct Timer timer [timer_count];
/* large objects at end */
struct Spc_Dsp dsp;
uint8_t extra_ram [rom_size];
uint8_t boot_rom [rom_size];
};
static void SPC_enable_rom( THIS, int enable )
{
if ( this->rom_enabled != enable )
{
this->rom_enabled = enable;
memcpy( RAM + rom_addr, (enable ? this->boot_rom : this->extra_ram), rom_size );
/* TODO: ROM can still get overwritten when DSP writes to echo buffer */
}
}
static void SPC_Init( THIS )
{
this->timer [0].shift = 4 + 3; /* 8 kHz */
this->timer [1].shift = 4 + 3; /* 8 kHz */
this->timer [2].shift = 4; /* 8 kHz */
/* Put STOP instruction around memory to catch PC underflow/overflow. */
memset( ram.padding1, 0xFF, sizeof ram.padding1 );
memset( ram.padding2, 0xFF, sizeof ram.padding2 );
/* A few tracks read from the last four bytes of IPL ROM */
this->boot_rom [sizeof this->boot_rom - 2] = 0xC0;
this->boot_rom [sizeof this->boot_rom - 1] = 0xFF;
memset( this->boot_rom, 0, sizeof this->boot_rom - 2 );
}
static void SPC_load_state( THIS, struct cpu_regs_t const* cpu_state,
const void* new_ram, const void* dsp_state )
{
memcpy(&(this->r),cpu_state,sizeof this->r);
/* ram */
memcpy( RAM, new_ram, sizeof RAM );
memcpy( this->extra_ram, RAM + rom_addr, sizeof this->extra_ram );
/* boot rom (have to force enable_rom() to update it) */
this->rom_enabled = !(RAM [0xF1] & 0x80);
SPC_enable_rom( this, !this->rom_enabled );
/* dsp */
/* some SPCs rely on DSP immediately generating one sample */
this->extra_cycles = 32;
DSP_reset( &this->dsp );
int i;
for ( i = 0; i < register_count; i++ )
DSP_write( &this->dsp, i, ((uint8_t const*) dsp_state) [i] );
/* timers */
for ( i = 0; i < timer_count; i++ )
{
struct Timer* t = &this->timer [i];
t->next_tick = -extra_clocks;
t->enabled = (RAM [0xF1] >> i) & 1;
if ( !t->enabled )
t->next_tick = timer_disabled_time;
t->count = 0;
t->counter = RAM [0xFD + i] & 15;
int p = RAM [0xFA + i];
if ( !p )
p = 0x100;
t->period = p;
}
/* Handle registers which already give 0 when read by
setting RAM and not changing it.
Put STOP instruction in registers which can be read,
to catch attempted execution. */
RAM [0xF0] = 0;
RAM [0xF1] = 0;
RAM [0xF3] = 0xFF;
RAM [0xFA] = 0;
RAM [0xFB] = 0;
RAM [0xFC] = 0;
RAM [0xFD] = 0xFF;
RAM [0xFE] = 0xFF;
RAM [0xFF] = 0xFF;
}
static void clear_echo( THIS )
{
if ( !(DSP_read( &this->dsp, 0x6C ) & 0x20) )
{
unsigned addr = 0x100 * DSP_read( &this->dsp, 0x6D );
size_t size = 0x800 * DSP_read( &this->dsp, 0x7D );
size_t max_size = sizeof RAM - addr;
if ( size > max_size )
size = sizeof RAM - addr;
memset( RAM + addr, 0xFF, size );
}
}
enum { spc_file_size = 0x10180 };
struct spc_file_t
{
char signature [27];
char unused [10];
uint8_t pc [2];
uint8_t a;
uint8_t x;
uint8_t y;
uint8_t status;
uint8_t sp;
char unused2 [212];
uint8_t ram [0x10000];
uint8_t dsp [128];
uint8_t ipl_rom [128];
};
static int SPC_load_spc( THIS, const void* data, long size )
{
struct spc_file_t const* spc = (struct spc_file_t const*) data;
struct cpu_regs_t regs;
if ( size < spc_file_size )
return -1;
if ( memcmp( spc->signature, "SNES-SPC700 Sound File Data", 27 ) != 0 )
return -1;
regs.pc = spc->pc [1] * 0x100 + spc->pc [0];
regs.a = spc->a;
regs.x = spc->x;
regs.y = spc->y;
regs.status = spc->status;
regs.sp = spc->sp;
if ( (unsigned long) size >= sizeof *spc )
memcpy( this->boot_rom, spc->ipl_rom, sizeof this->boot_rom );
SPC_load_state( this, &regs, spc->ram, spc->dsp );
clear_echo(this);
return 0;
}
/**************** DSP interaction ****************/
static void SPC_run_dsp_( THIS, long time ) ICODE_ATTR;
static void SPC_run_dsp_( THIS, long time )
{
/* divide by clocks_per_sample */
int count = ((time - this->next_dsp) >> 5) + 1;
int32_t* buf = this->sample_buf;
this->sample_buf = buf + count;
this->next_dsp += count * clocks_per_sample;
DSP_run( &this->dsp, count, buf );
}
static inline void SPC_run_dsp( THIS, long time )
{
if ( time >= this->next_dsp )
SPC_run_dsp_( this, time );
}
static int SPC_read( THIS, unsigned addr, long const time ) ICODE_ATTR;
static int SPC_read( THIS, unsigned addr, long const time )
{
int result = RAM [addr];
if ( ((unsigned) (addr - 0xF0)) < 0x10 )
{
assert( 0xF0 <= addr && addr <= 0xFF );
/* counters */
int i = addr - 0xFD;
if ( i >= 0 )
{
struct Timer* t = &this->timer [i];
Timer_run( t, time );
result = t->counter;
t->counter = 0;
}
/* dsp */
else if ( addr == 0xF3 )
{
SPC_run_dsp( this, time );
result = DSP_read( &this->dsp, RAM [0xF2] & 0x7F );
}
}
return result;
}
static void SPC_write( THIS, unsigned addr, int data, long const time )
ICODE_ATTR;
static void SPC_write( THIS, unsigned addr, int data, long const time )
{
/* first page is very common */
if ( addr < 0xF0 )
{
RAM [addr] = (uint8_t) data;
}
else switch ( addr )
{
/* RAM */
default:
if ( addr < rom_addr )
{
RAM [addr] = (uint8_t) data;
}
else
{
this->extra_ram [addr - rom_addr] = (uint8_t) data;
if ( !this->rom_enabled )
RAM [addr] = (uint8_t) data;
}
break;
/* DSP */
/*case 0xF2:*/ /* mapped to RAM */
case 0xF3: {
SPC_run_dsp( this, time );
int reg = RAM [0xF2];
if ( reg < register_count ) {
DSP_write( &this->dsp, reg, data );
}
else {
/*dprintf( "DSP write to $%02X\n", (int) reg ); */
}
break;
}
case 0xF0: /* Test register */
/*dprintf( "Wrote $%02X to $F0\n", (int) data ); */
break;
/* Config */
case 0xF1:
{
int i;
/* timers */
for ( i = 0; i < timer_count; i++ )
{
struct Timer * t = this->timer+i;
if ( !(data & (1 << i)) )
{
t->enabled = 0;
t->next_tick = timer_disabled_time;
}
else if ( !t->enabled )
{
/* just enabled */
t->enabled = 1;
t->counter = 0;
t->count = 0;
t->next_tick = time;
}
}
/* port clears */
if ( data & 0x10 )
{
RAM [0xF4] = 0;
RAM [0xF5] = 0;
}
if ( data & 0x20 )
{
RAM [0xF6] = 0;
RAM [0xF7] = 0;
}
SPC_enable_rom( this, (data & 0x80) != 0 );
break;
}
/* Ports */
case 0xF4:
case 0xF5:
case 0xF6:
case 0xF7:
/* to do: handle output ports */
break;
/* verified on SNES that these are read/write (RAM) */
/*case 0xF8: */
/*case 0xF9: */
/* Timers */
case 0xFA:
case 0xFB:
case 0xFC: {
int i = addr - 0xFA;
struct Timer* t = &this->timer [i];
if ( (t->period & 0xFF) != data )
{
Timer_run( t, time );
this->timer[i].period = data ? data : 0x100;
}
break;
}
/* Counters (cleared on write) */
case 0xFD:
case 0xFE:
case 0xFF:
/*dprintf( "Wrote to counter $%02X\n", (int) addr ); */
this->timer [addr - 0xFD].counter = 0;
break;
}
}
#include "spc/Spc_Cpu.h"
/**************** Sample generation ****************/
static int SPC_play( THIS, long count, int32_t* out ) ICODE_ATTR;
static int SPC_play( THIS, long count, int32_t* out )
{
int i;
assert( count % 2 == 0 ); /* output is always in pairs of samples */
long start_time = -(count >> 1) * clocks_per_sample - extra_clocks;
/* DSP output is made on-the-fly when DSP registers are read or written */
this->sample_buf = out;
this->next_dsp = start_time + clocks_per_sample;
/* Localize timer next_tick times and run them to the present to prevent
a running but ignored timer's next_tick from getting too far behind
and overflowing. */
for ( i = 0; i < timer_count; i++ )
{
struct Timer* t = &this->timer [i];
if ( t->enabled )
{
t->next_tick += start_time + extra_clocks;
Timer_run( t, start_time );
}
}
/* Run from start_time to 0, pre-advancing by extra cycles from last run */
this->extra_cycles = CPU_run( this, start_time + this->extra_cycles ) +
extra_clocks;
if ( this->extra_cycles < 0 )
{
/*dprintf( "Unhandled instruction $%02X, pc = $%04X\n",
(int) CPU_read( r.pc ), (unsigned) r.pc ); */
return -1;
}
/* Catch DSP up to present */
#if 0
ENTER_TIMER(cpu);
#endif
SPC_run_dsp( this, -extra_clocks );
#if 0
EXIT_TIMER(cpu);
#endif
assert( this->next_dsp == clocks_per_sample - extra_clocks );
assert( this->sample_buf - out == count );
return 0;
}
/**************** ID666 parsing ****************/
struct {
unsigned char isBinary;
char song[32];
char game[32];
char dumper[16];
char comments[32];
int day,month,year;
unsigned long length;
unsigned long fade;
char artist[32];
unsigned char muted;
unsigned char emulator;
} ID666;
static int LoadID666(unsigned char *buf) {
unsigned char *ib=buf;
int isbinary = 1;
int i;
memcpy(ID666.song,ib,32);
ID666.song[31]=0;
ib+=32;
memcpy(ID666.game,ib,32);
ID666.game[31]=0;
ib+=32;
memcpy(ID666.dumper,ib,16);
ID666.dumper[15]=0;
ib+=16;
memcpy(ID666.comments,ib,32);
ID666.comments[31]=0;
ib+=32;
/* Ok, now comes the fun part. */
/* Date check */
if(ib[2] == '/' && ib[5] == '/' )
isbinary = 0;
/* Reserved bytes check */
if(ib[0xD2 - 0x2E - 112] >= '0' &&
ib[0xD2 - 0x2E - 112] <= '9' &&
ib[0xD3 - 0x2E - 112] == 0x00)
isbinary = 0;
/* is length & fade only digits? */
for (i=0;i<8 && (
(ib[0xA9 - 0x2E - 112+i]>='0'&&ib[0xA9 - 0x2E - 112+i]<='9') ||
ib[0xA9 - 0x2E - 112+i]=='\0');
i++);
if (i==8) isbinary=0;
ID666.isBinary = isbinary;
if(isbinary) {
DEBUGF("binary tag detected\n");
ID666.year=*ib;
ib++;
ID666.year|=*ib<<8;
ib++;
ID666.month=*ib;
ib++;
ID666.day=*ib;
ib++;
ib+=7;
ID666.length=*ib;
ib++;
ID666.length|=*ib<<8;
ib++;
ID666.length|=*ib<<16;
ID666.length*=1000;
ib++;
ID666.fade=*ib;
ib++;
ID666.fade|=*ib<<8;
ib++;
ID666.fade|=*ib<<16;
ib++;
ID666.fade|=*ib<<24;
ib++;
memcpy(ID666.artist,ib,32);
ID666.artist[31]=0;
ib+=32;
ID666.muted=*ib;
ib++;
ID666.emulator=*ib;
ib++;
} else {
int year, month, day;
unsigned long tmp;
char buf[64];
DEBUGF("text tag detected\n");
year=month=day=0;
ib+=11;
memcpy(buf, ib, 3);
buf[3] = 0;
tmp = 0;
for (i=0;i<3 && buf[i]>='0' && buf[i]<='9';i++) tmp=tmp*10+buf[i]-'0';
ID666.length = tmp * 1000;
ib+=3;
memcpy(buf, ib, 5);
buf[5] = 0;
tmp = 0;
for (i=0;i<5 && buf[i]>='0' && buf[i]<='9';i++) tmp=tmp*10+buf[i]-'0';
ID666.fade = tmp;
ib+=5;
memcpy(ID666.artist,ib,32);
ID666.artist[31]=0;
ib+=32;
/*I have no idea if this is right or not.*/
ID666.muted=*ib;
ib++;
memcpy(buf, ib, 1);
buf[1] = 0;
tmp = 0;
ib++;
}
return 1;
}
/**************** Codec ****************/
static int32_t samples[WAV_CHUNK_SIZE*2] IBSS_ATTR;
static struct Spc_Emu spc_emu IDATA_ATTR;
enum {sample_rate = 32000};
/* The main decoder loop */
static int play_track( void )
{
int sampleswritten=0;
unsigned long fadestartsample = ID666.length*(long long) sample_rate/1000;
unsigned long fadeendsample = (ID666.length+ID666.fade)*(long long) sample_rate/1000;
int fadedec = 0;
int fadevol = 0x7fffffffl;
if (fadeendsample>fadestartsample)
fadedec=0x7fffffffl/(fadeendsample-fadestartsample)+1;
ENTER_TIMER(total);
while ( 1 )
{
ci->yield();
if (ci->stop_codec || ci->new_track) {
break;
}
if (ci->seek_time) {
int curtime = sampleswritten*1000LL/sample_rate;
DEBUGF("seek to %d\ncurrently at %d\n",ci->seek_time,curtime);
if (ci->seek_time < curtime) {
DEBUGF("seek backwards = reset\n");
ci->seek_complete();
return 1;
}
ci->seek_complete();
}
ENTER_TIMER(render);
/* fill samples buffer */
if ( SPC_play(&spc_emu,WAV_CHUNK_SIZE*2,samples) )
assert( false );
EXIT_TIMER(render);
sampleswritten+=WAV_CHUNK_SIZE;
/* is track timed? */
if (ci->global_settings->repeat_mode!=REPEAT_ONE && ci->id3->length) {
unsigned long curtime = sampleswritten*1000LL/sample_rate;
unsigned long lasttimesample = (sampleswritten-WAV_CHUNK_SIZE);
/* fade? */
if (curtime>ID666.length)
{
int i;
for (i=0;i<WAV_CHUNK_SIZE;i++) {
if (lasttimesample+i>fadestartsample) {
if (fadevol>0) {
samples[i] = (samples[i]*(fadevol>>24))>>7;
samples[i+WAV_CHUNK_SIZE] = (samples[i+WAV_CHUNK_SIZE]*(fadevol>>24))>>7;
} else samples[i]=samples[i+WAV_CHUNK_SIZE]=0;
fadevol-=fadedec;
}
}
}
/* end? */
if (lasttimesample>=fadeendsample)
break;
}
ci->pcmbuf_insert(samples, samples+WAV_CHUNK_SIZE, WAV_CHUNK_SIZE);
if (ci->global_settings->repeat_mode!=REPEAT_ONE)
ci->set_elapsed(sampleswritten*1000LL/sample_rate);
else
ci->set_elapsed(0);
}
EXIT_TIMER(total);
return 0;
}
/* this is the codec entry point */
enum codec_status codec_main(void)
{
memcpy( spc_emu.cycle_table, cycle_table, sizeof cycle_table );
do
{
DEBUGF("SPC: next_track\n");
if (codec_init()) {
return CODEC_ERROR;
}
DEBUGF("SPC: after init\n");
ci->configure(DSP_SET_SAMPLE_DEPTH, 24);
ci->configure(DSP_SET_FREQUENCY, sample_rate);
ci->configure(DSP_SET_STEREO_MODE, STEREO_NONINTERLEAVED);
/* wait for track info to load */
while (!*ci->taginfo_ready && !ci->stop_codec)
ci->sleep(1);
/* Read the entire file */
DEBUGF("SPC: request initial buffer\n");
ci->configure(CODEC_SET_FILEBUF_WATERMARK, ci->filesize);
ci->seek_buffer(0);
size_t buffersize;
uint8_t* buffer = ci->request_buffer(&buffersize, ci->filesize);
if (!buffer) {
return CODEC_ERROR;
}
DEBUGF("SPC: read size = 0x%x\n",buffersize);
do
{
SPC_Init(&spc_emu);
if (SPC_load_spc(&spc_emu,buffer,buffersize)) {
DEBUGF("SPC load failure\n");
return CODEC_ERROR;
}
LoadID666(buffer+0x2e);
if (ci->global_settings->repeat_mode!=REPEAT_ONE && ID666.length==0) {
ID666.length=3*60*1000; /* 3 minutes */
ID666.fade=5*1000; /* 5 seconds */
}
ci->id3->length = ID666.length+ID666.fade;
ci->id3->title = ID666.song;
ci->id3->album = ID666.game;
ci->id3->artist = ID666.artist;
reset_profile_timers();
}
while ( play_track() );
print_timers(ci->id3->path);
}
while ( ci->request_next_track() );
return CODEC_OK;
}