xref: /illumos-kvm-cmd/hw/gusemu.h (revision 68396ea9)
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 /* doesnt 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  #include <stdint.h>
38  typedef int8_t GUSchar;
39  typedef uint8_t GUSbyte;
40  typedef uint16_t GUSword;
41  typedef uint32_t GUSdword;
42  typedef int16_t GUSsample;
43 #endif
44 
45 typedef struct _GUSEmuState
46 {
47  GUSbyte *himemaddr; /* 1024*1024 bytes used for storing uploaded samples (+32 additional bytes for read padding) */
48  GUSbyte *gusdatapos; /* (gusdataend-gusdata) bytes used for storing emulated GF1/mixer register states (32*32+4 bytes in initial GUSemu32 version) */
49  uint32_t gusirq;
50  uint32_t gusdma;
51  unsigned int timer1fraction;
52  unsigned int timer2fraction;
53  void *opaque;
54 } GUSEmuState;
55 
56 /* ** Callback functions needed: */
57 /* NMI is defined as hwirq=-1 (not supported (yet?)) */
58 /* GUS_irqrequest returns the number of IRQs actually scheduled into the virtual machine */
59 /* Level triggered IRQ simulations normally return 1 */
60 /* Event triggered IRQ simulation can safely ignore GUS_irqclear calls */
61 int  GUS_irqrequest(GUSEmuState *state, int hwirq, int num);/* needed in both mixer and bus emulation functions. */
62 void GUS_irqclear(  GUSEmuState *state, int hwirq); /* used by gus_write() only - can be left empty for mixer functions */
63 void GUS_dmarequest(GUSEmuState *state);            /* used by gus_write() only - can be left empty for mixer functions */
64 
65 /* ** ISA bus interface functions: */
66 
67 /* Port I/O handlers */
68 /* support the following ports: */
69 /* 2x0,2x6,2x8...2xF,3x0...3x7;  */
70 /* optional: 388,389 (at least writes should be forwarded or some GUS detection algorithms will fail) */
71 /* data is passed in host byte order */
72 unsigned int gus_read( GUSEmuState *state, int port, int size);
73 void         gus_write(GUSEmuState *state, int port, int size, unsigned int data);
74 /* size is given in bytes (1 for byte, 2 for word) */
75 
76 /* DMA data transfer function */
77 /* data pointed to is passed in native x86 order */
78 void gus_dma_transferdata(GUSEmuState *state, char *dma_addr, unsigned int count, int TC);
79 /* Called back by GUS_start_DMA as soon as the emulated DMA controller is ready for a transfer to or from GUS */
80 /* (might be immediately if the DMA controller was programmed first) */
81 /* dma_addr is an already translated address directly pointing to the beginning of the memory block */
82 /* do not forget to update DMA states after the call, including the DREQ and TC flags */
83 /* it is possible to break down a single transfer into multiple ones, but take care that: */
84 /* -dma_count is actually count-1 */
85 /* -before and during a transfer, DREQ is set and TC cleared */
86 /* -when calling gus_dma_transferdata(), TC is only set true for call transfering the last byte */
87 /* -after the last transfer, DREQ is cleared and TC is set */
88 
89 /* ** GF1 mixer emulation functions: */
90 /* Usually, gus_irqgen should be called directly after gus_mixvoices if you can meet the recommended ranges. */
91 /* If the interrupts are executed immediately (i.e., are synchronous), it may be useful to break this */
92 /* down into a sequence of gus_mixvoice();gus_irqgen(); calls while mixing an audio block. */
93 /* If the interrupts are asynchronous, it may be needed to use a separate thread mixing into a temporary */
94 /* audio buffer in order to avoid quality loss caused by large numsamples and elapsed_time values. */
95 
96 void gus_mixvoices(GUSEmuState *state, unsigned int playback_freq, unsigned int numsamples, GUSsample *bufferpos);
97 /* recommended range: 10 < numsamples < 100 */
98 /* lower values may result in increased rounding error, higher values often cause audible timing delays */
99 
100 void gus_irqgen(GUSEmuState *state, unsigned int elapsed_time);
101 /* recommended range: 80us < elapsed_time < max(1000us, numsamples/playback_freq) */
102 /* lower values won´t provide any benefit at all, higher values can cause audible timing delays */
103 /* note: masked timers are also calculated by this function, thus it might be needed even without any IRQs in use! */
104 
105 #endif  /* gusemu.h */
106