LXR qemu/hw/audio/gusemu.h

   1/*
   2 * GUSEMU32 - API
   3 *
   4 * Copyright (C) 2000-2007 Tibor "TS" Schütz
   5 *
   6 * Permission is hereby granted, free of charge, to any person obtaining a copy
   7 * of this software and associated documentation files (the "Software"), to deal
   8 * in the Software without restriction, including without limitation the rights
   9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10 * copies of the Software, and to permit persons to whom the Software is
  11 * furnished to do so, subject to the following conditions:
  12 *
  13 * The above copyright notice and this permission notice shall be included in
  14 * all copies or substantial portions of the Software.
  15 *
  16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22 * THE SOFTWARE.
  23 */
  24
  25#ifndef GUSEMU_H
  26#define GUSEMU_H
  27
  28/* data types (need to be adjusted if neither a VC6 nor a C99 compatible compiler is used) */
  29
  30#if defined _WIN32 && defined _MSC_VER /* doesn't support other win32 compilers yet, do it yourself... */
  31 typedef unsigned char GUSbyte;
  32 typedef unsigned short GUSword;
  33 typedef unsigned int GUSdword;
  34 typedef signed char GUSchar;
  35 typedef signed short GUSsample;
  36#else
  37 typedef int8_t GUSchar;
  38 typedef uint8_t GUSbyte;
  39 typedef uint16_t GUSword;
  40 typedef uint32_t GUSdword;
  41 typedef int16_t GUSsample;
  42#endif
  43
  44typedef struct _GUSEmuState
  45{
  46 GUSbyte *himemaddr; /* 1024*1024 bytes used for storing uploaded samples (+32 additional bytes for read padding) */
  47 GUSbyte *gusdatapos; /* (gusdataend-gusdata) bytes used for storing emulated GF1/mixer register states (32*32+4 bytes in initial GUSemu32 version) */
  48 uint32_t gusirq;
  49 uint32_t gusdma;
  50 unsigned int timer1fraction;
  51 unsigned int timer2fraction;
  52 void *opaque;
  53} GUSEmuState;
  54
  55/* ** Callback functions needed: */
  56/* NMI is defined as hwirq=-1 (not supported (yet?)) */
  57/* GUS_irqrequest returns the number of IRQs actually scheduled into the virtual machine */
  58/* Level triggered IRQ simulations normally return 1 */
  59/* Event triggered IRQ simulation can safely ignore GUS_irqclear calls */
  60int  GUS_irqrequest(GUSEmuState *state, int hwirq, int num);/* needed in both mixer and bus emulation functions. */
  61void GUS_irqclear(  GUSEmuState *state, int hwirq); /* used by gus_write() only - can be left empty for mixer functions */
  62void GUS_dmarequest(GUSEmuState *state);            /* used by gus_write() only - can be left empty for mixer functions */
  63
  64/* ** ISA bus interface functions: */
  65
  66/* Port I/O handlers */
  67/* support the following ports: */
  68/* 2x0,2x6,2x8...2xF,3x0...3x7;  */
  69/* optional: 388,389 (at least writes should be forwarded or some GUS detection algorithms will fail) */
  70/* data is passed in host byte order */
  71unsigned int gus_read( GUSEmuState *state, int port, int size);
  72void         gus_write(GUSEmuState *state, int port, int size, unsigned int data);
  73/* size is given in bytes (1 for byte, 2 for word) */
  74
  75/* DMA data transfer function */
  76/* data pointed to is passed in native x86 order */
  77void gus_dma_transferdata(GUSEmuState *state, char *dma_addr, unsigned int count, int TC);
  78/* Called back by GUS_start_DMA as soon as the emulated DMA controller is ready for a transfer to or from GUS */
  79/* (might be immediately if the DMA controller was programmed first) */
  80/* dma_addr is an already translated address directly pointing to the beginning of the memory block */
  81/* do not forget to update DMA states after the call, including the DREQ and TC flags */
  82/* it is possible to break down a single transfer into multiple ones, but take care that: */
  83/* -dma_count is actually count-1 */
  84/* -before and during a transfer, DREQ is set and TC cleared */
  85/* -when calling gus_dma_transferdata(), TC is only set true for call transferring the last byte */
  86/* -after the last transfer, DREQ is cleared and TC is set */
  87
  88/* ** GF1 mixer emulation functions: */
  89/* Usually, gus_irqgen should be called directly after gus_mixvoices if you can meet the recommended ranges. */
  90/* If the interrupts are executed immediately (i.e., are synchronous), it may be useful to break this */
  91/* down into a sequence of gus_mixvoice();gus_irqgen(); calls while mixing an audio block. */
  92/* If the interrupts are asynchronous, it may be needed to use a separate thread mixing into a temporary */
  93/* audio buffer in order to avoid quality loss caused by large numsamples and elapsed_time values. */
  94
  95void gus_mixvoices(GUSEmuState *state, unsigned int playback_freq, unsigned int numsamples, GUSsample *bufferpos);
  96/* recommended range: 10 < numsamples < 100 */
  97/* lower values may result in increased rounding error, higher values often cause audible timing delays */
  98
  99void gus_irqgen(GUSEmuState *state, unsigned int elapsed_time);
 100/* recommended range: 80us < elapsed_time < max(1000us, numsamples/playback_freq) */
 101/* lower values won´t provide any benefit at all, higher values can cause audible timing delays */
 102/* note: masked timers are also calculated by this function, thus it might be needed even without any IRQs in use! */
 103
 104#endif  /* gusemu.h */
 105