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/*
SDL - Simple DirectMedia Layer
Copyright (C) 1997-2012 Sam Lantinga
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Sam Lantinga
slouken@libsdl.org
*/
/*
Audio interrupts
Patrice Mandin, Didier Méquignon
*/
.text
.globl _SDL_MintAudio_Callback
.globl _SDL_MintAudio_XbiosInterrupt
.globl _SDL_MintAudio_XbiosInterruptMeasureClock
.globl _SDL_MintAudio_Dma8Interrupt
.globl _SDL_MintAudio_StfaInterrupt
.globl _SDL_MintAudio_mutex
.globl _SDL_MintAudio_audiobuf
.globl _SDL_MintAudio_numbuf
.globl _SDL_MintAudio_audiosize
.globl _SDL_MintAudio_clocktics
.globl _SDL_MintAudio_hasfpu
.globl _SDL_MintAudio_stfa
/*
How it works:
- Audio is playing buffer #0 (resp. #1)
- We must calculate a sample in buffer #1 (resp. #0)
so we first call the callback to do it
- Then we swap the buffers
*/
#define savptr 0x4a2
#define savamt 0x46
/*--- Save/restore FPU context ---*/
#if defined(__mcoldfire__)
#define SAVE_FPU_CONTEXT \
lea sp@(-216),sp; \
fsave sp@; \
fmovel fpiar,sp@-; \
lea sp@(-64),sp; \
fmovemd fp0-fp7,sp@
#define RESTORE_FPU_CONTEXT \
fmovemd sp@,fp0-fp7; \
lea sp@(64),sp; \
fmovel sp@+,fpiar; \
frestore sp@; \
lea sp@(216),sp
#else
#define SAVE_FPU_CONTEXT \
.chip 68k/68881; \
fsave sp@-; \
fmoveml fpcr/fpsr/fpiar,sp@-; \
fmovemx fp0-fp7,sp@-; \
.chip 68k
#define RESTORE_FPU_CONTEXT \
.chip 68k/68881; \
fmovemx sp@+,fp0-fp7; \
fmoveml sp@+,fpcr/fpsr/fpiar; \
frestore sp@+; \
.chip 68k
#endif
/*--- Xbios interrupt vector to measure Falcon external clock ---*/
_SDL_MintAudio_XbiosInterruptMeasureClock: /* 1 mS */
#if defined(__mcoldfire__)
movel d0,sp@-
moveql #0,d0
btst d0,0xFFFF8901:w /* state DMA sound */
#else
btst #0,0xFFFF8901:w /* state DMA sound */
#endif
beqs SDL_MintAudio_EndIntMeasure
addql #1,_SDL_MintAudio_clocktics
SDL_MintAudio_EndIntMeasure:
#if defined(__mcoldfire__)
moveql #5,d0
bclr d0,0xFFFFFA0F:w /* Clear service bit */
movel sp@+,d0
#else
bclr #5,0xFFFFFA0F:w /* Clear service bit */
#endif
rte
/*--- Xbios interrupt vector ---*/
_SDL_MintAudio_XbiosInterrupt:
#if defined(__mcoldfire__)
lea sp@(-60),sp
moveml d0-d7/a0-a6,sp@
#else
moveml d0-d7/a0-a6,sp@-
#endif
/* Reenable interrupts, so other interrupts can work */
movew #0x2300,sr
/* Clear service bit, so other MFP interrupts can work */
#if defined(__mcoldfire__)
moveql #5,d0
bclr d0,0xfffffa0f:w
#else
bclr #5,0xfffffa0f:w
#endif
/* Check if we are not already running */
tstw _SDL_MintAudio_mutex
bne SDL_MintAudio_XbiosEnd
#if defined(__mcoldfire__)
movew _SDL_MintAudio_mutex,d0
notl d0
movew d0,_SDL_MintAudio_mutex
movew _SDL_MintAudio_numbuf,d1
eorl #1,d1
movew d1,_SDL_MintAudio_numbuf
#else
notw _SDL_MintAudio_mutex
/* Swap buffers */
eorw #1,_SDL_MintAudio_numbuf
#endif
/* Save FPU if needed */
tstw _SDL_MintAudio_hasfpu
beqs SDL_MintAudio_Xbios_nofpu1
SAVE_FPU_CONTEXT
SDL_MintAudio_Xbios_nofpu1:
/* Callback */
jsr _SDL_MintAudio_Callback
/* Restore FPU if needed */
tstw _SDL_MintAudio_hasfpu
beqs SDL_MintAudio_Xbios_nofpu2
RESTORE_FPU_CONTEXT
SDL_MintAudio_Xbios_nofpu2:
/* Reserve space for registers */
#if defined(__mcoldfire__)
movel #savamt,d0
subl d0,savptr
#else
subl #savamt,savptr
#endif
/* Set new buffer */
moveq #0,d0
movel _SDL_MintAudio_audiosize,d1
movew _SDL_MintAudio_numbuf,d0
lsll #2,d0
lea _SDL_MintAudio_audiobuf,a0
movel a0@(d0:l),a1
lea a1@(d1:l),a2
movel a2,sp@-
movel a1,sp@-
clrw sp@-
movew #131,sp@-
trap #14
lea sp@(12),sp
/* Restore registers space */
#if defined(__mcoldfire__)
movel #savamt,d0
addl d0,savptr
#else
addl #savamt,savptr
#endif
clrw _SDL_MintAudio_mutex
SDL_MintAudio_XbiosEnd:
#if defined(__mcoldfire__)
moveml sp@,d0-d7/a0-a6
lea sp@(60),sp
#else
moveml sp@+,d0-d7/a0-a6
#endif
rte
/*--- DMA 8 bits interrupt vector ---*/
_SDL_MintAudio_Dma8Interrupt:
#if defined(__mcoldfire__)
lea sp@(-16),sp
moveml d0-d1/a0-a1,sp@
#else
moveml d0-d1/a0-a1,sp@-
#endif
/* Reenable interrupts, so other interrupts can work */
movew #0x2300,sr
/* Clear service bit, so other MFP interrupts can work */
#if defined(__mcoldfire__)
moveql #5,d0
bclr d0,0xfffffa0f:w
#else
bclr #5,0xfffffa0f:w
#endif
/* Check if we are not already running */
tstw _SDL_MintAudio_mutex
bne SDL_MintAudio_Dma8End
#if defined(__mcoldfire__)
movew _SDL_MintAudio_mutex,d0
notl d0
movew d0,_SDL_MintAudio_mutex
movew _SDL_MintAudio_numbuf,d1
eorl #1,d1
movew d1,_SDL_MintAudio_numbuf
#else
notw _SDL_MintAudio_mutex
/* Swap buffers */
eorw #1,_SDL_MintAudio_numbuf
#endif
/* Save FPU if needed */
tstw _SDL_MintAudio_hasfpu
beqs SDL_MintAudio_Dma8_nofpu1
SAVE_FPU_CONTEXT
SDL_MintAudio_Dma8_nofpu1:
/* Callback */
jsr _SDL_MintAudio_Callback
/* Restore FPU if needed */
tstw _SDL_MintAudio_hasfpu
beqs SDL_MintAudio_Dma8_nofpu2
RESTORE_FPU_CONTEXT
SDL_MintAudio_Dma8_nofpu2:
/* Set new buffer */
moveq #0,d0
movew _SDL_MintAudio_numbuf,d0
lsll #2,d0
lea _SDL_MintAudio_audiobuf,a0
movel a0@(d0:l),d1
/* Modify DMA addresses */
lea 0xffff8900:w,a0
movel d1,d0
moveb d0,a0@(0x07) /* Start address */
lsrl #8,d0
moveb d0,a0@(0x05)
lsrl #8,d0
moveb d0,a0@(0x03)
addl _SDL_MintAudio_audiosize,d1
movel d1,d0
moveb d0,a0@(0x13) /* End address */
lsrl #8,d0
moveb d0,a0@(0x11)
lsrl #8,d0
moveb d0,a0@(0x0f)
clrw _SDL_MintAudio_mutex
SDL_MintAudio_Dma8End:
#if defined(__mcoldfire__)
moveml sp@,d0-d1/a0-a1
lea sp@(16),sp
#else
moveml sp@+,d0-d1/a0-a1
#endif
rte
/*--- STFA interrupt vector ---*/
STFA_SOUND_START = 6
STFA_SOUND_END = STFA_SOUND_START+8
_SDL_MintAudio_StfaInterrupt:
/* Reenable interrupts, so other interrupts can work */
movew #0x2300,sr
/* Check if we are not already running */
tstw _SDL_MintAudio_mutex
#if defined(__mcoldfire__)
bne SDL_MintAudio_StfaEnd
lea sp@(-60),sp
moveml d0-d7/a0-a6,sp@
movew _SDL_MintAudio_mutex,d0
notl d0
movew d0,_SDL_MintAudio_mutex
movew _SDL_MintAudio_numbuf,d1
eorl #1,d1
movew d1,_SDL_MintAudio_numbuf
#else
bnes SDL_MintAudio_StfaEnd
moveml d0-d7/a0-a6,sp@-
notw _SDL_MintAudio_mutex
/* Swap buffers */
eorw #1,_SDL_MintAudio_numbuf
#endif
/* Save FPU if needed */
tstw _SDL_MintAudio_hasfpu
beqs SDL_MintAudio_Stfa_nofpu1
SAVE_FPU_CONTEXT
SDL_MintAudio_Stfa_nofpu1:
/* Callback */
jsr _SDL_MintAudio_Callback
/* Restore FPU if needed */
tstw _SDL_MintAudio_hasfpu
beqs SDL_MintAudio_Stfa_nofpu2
RESTORE_FPU_CONTEXT
SDL_MintAudio_Stfa_nofpu2:
/* Set new buffer */
moveq #0,d0
movel _SDL_MintAudio_stfa,a1
movew _SDL_MintAudio_numbuf,d0
lsll #2,d0
lea _SDL_MintAudio_audiobuf,a0
movel a0@(d0:l),d1
/* Modify STFA replay buffers */
movel d1,a1@(STFA_SOUND_START)
addl _SDL_MintAudio_audiosize,d1
movel d1,a1@(STFA_SOUND_END)
#if defined(__mcoldfire__)
moveml sp@,d0-d7/a0-a6
lea sp@(60),sp
#else
moveml sp@+,d0-d7/a0-a6
#endif
clrw _SDL_MintAudio_mutex
SDL_MintAudio_StfaEnd:
rte
|
