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