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 short GUSword; 32 typedef unsigned int GUSdword; 33 typedef signed short GUSsample; 34 #else 35 typedef uint16_t GUSword; 36 typedef uint32_t GUSdword; 37 typedef int16_t GUSsample; 38 #endif 39 40 typedef struct _GUSEmuState 41 { 42 uint8_t *himemaddr; /* 1024*1024 bytes used for storing uploaded samples (+32 additional bytes for read padding) */ 43 uint8_t *gusdatapos; /* (gusdataend-gusdata) bytes used for storing emulated GF1/mixer register states (32*32+4 bytes in initial GUSemu32 version) */ 44 uint32_t gusirq; 45 uint32_t gusdma; 46 unsigned int timer1fraction; 47 unsigned int timer2fraction; 48 void *opaque; 49 } GUSEmuState; 50 51 /* ** Callback functions needed: */ 52 /* NMI is defined as hwirq=-1 (not supported (yet?)) */ 53 /* GUS_irqrequest returns the number of IRQs actually scheduled into the virtual machine */ 54 /* Level triggered IRQ simulations normally return 1 */ 55 /* Event triggered IRQ simulation can safely ignore GUS_irqclear calls */ 56 int GUS_irqrequest(GUSEmuState *state, int hwirq, int num);/* needed in both mixer and bus emulation functions. */ 57 void GUS_irqclear( GUSEmuState *state, int hwirq); /* used by gus_write() only - can be left empty for mixer functions */ 58 void GUS_dmarequest(GUSEmuState *state); /* used by gus_write() only - can be left empty for mixer functions */ 59 60 /* ** ISA bus interface functions: */ 61 62 /* Port I/O handlers */ 63 /* support the following ports: */ 64 /* 2x0,2x6,2x8...2xF,3x0...3x7; */ 65 /* optional: 388,389 (at least writes should be forwarded or some GUS detection algorithms will fail) */ 66 /* data is passed in host byte order */ 67 unsigned int gus_read( GUSEmuState *state, int port, int size); 68 void gus_write(GUSEmuState *state, int port, int size, unsigned int data); 69 /* size is given in bytes (1 for byte, 2 for word) */ 70 71 /* DMA data transfer function */ 72 /* data pointed to is passed in native x86 order */ 73 void gus_dma_transferdata(GUSEmuState *state, char *dma_addr, unsigned int count, int TC); 74 /* Called back by GUS_start_DMA as soon as the emulated DMA controller is ready for a transfer to or from GUS */ 75 /* (might be immediately if the DMA controller was programmed first) */ 76 /* dma_addr is an already translated address directly pointing to the beginning of the memory block */ 77 /* do not forget to update DMA states after the call, including the DREQ and TC flags */ 78 /* it is possible to break down a single transfer into multiple ones, but take care that: */ 79 /* -dma_count is actually count-1 */ 80 /* -before and during a transfer, DREQ is set and TC cleared */ 81 /* -when calling gus_dma_transferdata(), TC is only set true for call transferring the last byte */ 82 /* -after the last transfer, DREQ is cleared and TC is set */ 83 84 /* ** GF1 mixer emulation functions: */ 85 /* Usually, gus_irqgen should be called directly after gus_mixvoices if you can meet the recommended ranges. */ 86 /* If the interrupts are executed immediately (i.e., are synchronous), it may be useful to break this */ 87 /* down into a sequence of gus_mixvoice();gus_irqgen(); calls while mixing an audio block. */ 88 /* If the interrupts are asynchronous, it may be needed to use a separate thread mixing into a temporary */ 89 /* audio buffer in order to avoid quality loss caused by large numsamples and elapsed_time values. */ 90 91 void gus_mixvoices(GUSEmuState *state, unsigned int playback_freq, unsigned int numsamples, GUSsample *bufferpos); 92 /* recommended range: 10 < numsamples < 100 */ 93 /* lower values may result in increased rounding error, higher values often cause audible timing delays */ 94 95 void gus_irqgen(GUSEmuState *state, unsigned int elapsed_time); 96 /* recommended range: 80us < elapsed_time < max(1000us, numsamples/playback_freq) */ 97 /* lower values won´t provide any benefit at all, higher values can cause audible timing delays */ 98 /* note: masked timers are also calculated by this function, thus it might be needed even without any IRQs in use! */ 99 100 #endif /* GUSEMU_H */ 101