10 #define IRQ_TO_INTR(x) ((x) + 8)
12 /* PIC command and data ports */
14 #define PIC1_DATA 0x21
16 #define PIC2_DATA 0xa1
17 /* PIC operation command word 2 bits */
18 #define OCW2_EOI (1 << 5)
20 #define REG_MIXPORT (base_port + 0x4)
21 #define REG_MIXDATA (base_port + 0x5)
22 #define REG_RESET (base_port + 0x6)
23 #define REG_RDATA (base_port + 0xa)
24 #define REG_WDATA (base_port + 0xc)
25 #define REG_WSTAT (base_port + 0xc)
26 #define REG_RSTAT (base_port + 0xe)
27 #define REG_INTACK (base_port + 0xe)
28 #define REG_INT16ACK (base_port + 0xf)
30 #define WSTAT_BUSY 0x80
31 #define RSTAT_RDY 0x80
34 #define CMD_SB16_OUT_RATE 0x41
35 #define CMD_SB16_IN_RATE 0x42
36 #define CMD_GET_VER 0xe1
38 /* start DMA playback/recording. combine with fifo/auto/input flags */
39 #define CMD_START_DMA8 0xc0
40 #define CMD_START_DMA16 0xb0
43 #define CMD_INPUT 0x08
45 /* immediately pause/continue */
46 #define CMD_PAUSE_DMA8 0xd0
47 #define CMD_ENABLE_OUTPUT 0xd1
48 #define CMD_DISABLE_OUTPUT 0xd3
49 #define CMD_CONT_DMA8 0xd4
50 #define CMD_PAUSE_DMA16 0xd5
51 #define CMD_CONT_DMA16 0xd6
53 /* end the playback at the end of the current buffer */
54 #define CMD_END_DMA16 0xd9
55 #define CMD_END_DMA8 0xda
57 /* transfer mode commands */
58 #define CMD_MODE_SIGNED 0x10
59 #define CMD_MODE_STEREO 0x20
62 #define MIX_IRQ_SEL 0x80
63 #define MIX_DMA_SEL 0x81
65 #define VER_MAJOR(x) ((x) >> 8)
66 #define VER_MINOR(x) ((x) & 0xff)
68 /* delay for about 1us */
69 #define iodelay() outportb(0x80, 0)
71 static void intr_handler();
72 static void start_dma_transfer(uint32_t addr, int size);
73 static void write_dsp(unsigned char val);
74 static unsigned char read_dsp(void);
75 static void write_mix(unsigned char val, int reg);
76 static unsigned char read_mix(int reg);
77 static int get_dsp_version(void);
78 static int sb16_detect_irq(void);
79 static int sb16_detect_dma(void);
80 static const char *sbname(int ver);
82 extern unsigned char low_mem_buffer[];
85 static int irq, dma_chan, dma16_chan;
95 base_port = 0x200 + ((i + 1) << 4);
96 if(sb_reset_dsp() == 0) {
97 ver = get_dsp_version();
98 sb16 = VER_MAJOR(ver) >= 4;
101 if(sb16_detect_irq() == -1) {
102 printf("sb_detect: failed to configure IRQ\n");
105 if(sb16_detect_dma() == -1) {
106 printf("sb_detect: failed to configure DMA\n");
110 printf("sb_detect: found %s (DSP v%d.%02d) at port %xh, irq %d, dma %d/%d\n",
111 sbname(ver), VER_MAJOR(ver), VER_MINOR(ver),
112 base_port, irq, dma_chan, dma16_chan);
115 /* XXX for old sound blasters, hard-code to IRQ 5 DMA 1 for now */
120 printf("sb_detect: found %s (DSP v%d.%02d) at port %xh\n", sbname(ver),
121 VER_MAJOR(ver), VER_MINOR(ver), base_port);
122 printf("sb_detect: old sound blaster dsp. assuming: irq 5, dma 1\n");
132 int sb_reset_dsp(void)
136 outportb(REG_RESET, 1);
137 for(i=0; i<3; i++) iodelay();
138 outportb(REG_RESET, 0);
140 for(i=0; i<128; i++) {
141 if(inportb(REG_RSTAT) & RSTAT_RDY) {
142 if(inportb(REG_RDATA) == 0xaa) {
151 void sb_set_output_rate(int rate)
154 write_dsp(CMD_SB16_OUT_RATE);
155 write_dsp(rate >> 8);
156 write_dsp(rate & 0xff);
158 int tcon = 256 - 1000000 / rate;
164 void *sb_buffer(int *size)
170 void sb_start(int rate, int nchan)
174 _go32_dpmi_seginfo intr;
176 /* for now just use the are after boot2. it's only used by the second stage
177 * loader and the VBE init code, none of which should overlap with audio playback.
178 * It's not necessary to use low memory. We can use up to the first 16mb for this,
179 * so if this becomes an issue, I'll make a DMA buffer allocator over 1mb.
180 * start the buffer from the next 64k boundary.
182 addr = ((uint32_t)low_mem_buffer + 0xffff) & 0xffff0000;
183 buffer = (void*)addr;
185 xfer_mode = CMD_MODE_SIGNED;
187 xfer_mode |= CMD_MODE_STEREO;
190 if(!(size = audio_callback(buffer, 65536))) {
194 intr.pm_offset = (intptr_t)intr_handler;
195 intr.pm_selector = _go32_my_cs();
197 _go32_dpmi_set_protected_mode_interrupt_vector(IRQ_TO_INTR(irq), &intr);
200 sb_set_output_rate(rate);
201 start_dma_transfer(addr, size);
202 write_dsp(CMD_ENABLE_OUTPUT);
207 write_dsp(CMD_PAUSE_DMA8);
210 void sb_continue(void)
212 write_dsp(CMD_CONT_DMA8);
217 write_dsp(CMD_END_DMA8);
218 write_dsp(CMD_DISABLE_OUTPUT);
221 void sb_volume(int vol)
226 static void intr_handler()
230 /* ask for more data */
231 if(!(size = audio_callback(buffer, 65536))) {
235 start_dma_transfer((uint32_t)buffer, size);
237 /* acknowledge the interrupt */
241 outportb(PIC2_CMD, OCW2_EOI);
243 outportb(PIC1_CMD, OCW2_EOI);
246 static void start_dma_transfer(uint32_t addr, int size)
248 /* set up the next DMA transfer */
249 dma_out(dma_chan, addr, size, DMA_SINGLE);
251 /* program the DSP to accept the DMA transfer */
252 write_dsp(CMD_START_DMA8 | CMD_FIFO);
253 write_dsp(xfer_mode);
255 write_dsp(size & 0xff);
256 write_dsp((size >> 8) & 0xff);
259 static void write_dsp(unsigned char val)
261 while(inportb(REG_WSTAT) & WSTAT_BUSY);
262 outportb(REG_WDATA, val);
265 static unsigned char read_dsp(void)
267 while((inportb(REG_RSTAT) & RSTAT_RDY) == 0);
268 return inportb(REG_RDATA);
271 static void write_mix(unsigned char val, int reg)
273 outportb(REG_MIXPORT, reg);
274 outportb(REG_MIXDATA, val);
277 static unsigned char read_mix(int reg)
279 outportb(REG_MIXPORT, reg);
280 return inportb(REG_MIXDATA);
283 static int get_dsp_version(void)
287 write_dsp(CMD_GET_VER);
291 return (major << 8) | minor;
294 static int sb16_detect_irq(void)
297 static int irqtab[] = {2, 5, 7, 10};
300 irqsel = read_mix(MIX_IRQ_SEL);
302 if(irqsel & (1 << i)) {
308 /* try to force IRQ 5 */
309 write_mix(2, MIX_IRQ_SEL); /* bit1 selects irq 5 */
311 /* re-read to verify */
312 irqsel = read_mix(MIX_IRQ_SEL);
322 static int sb16_detect_dma(void)
325 static int dmatab[] = {0, 1, -1, 3, -1, 5, 6, 7};
329 dmasel = read_mix(MIX_DMA_SEL);
331 if(dmasel & (1 << i)) {
332 dma_chan = dmatab[i];
337 if(dmasel & (1 << i)) {
338 dma16_chan = dmatab[i];
343 /* try to force DMA 1 */
346 if(dma16_chan == -1) {
347 /* try to force 16bit DMA 5 */
351 if(dma_chan == -1 || dma16_chan == -1) {
352 write_mix(dmasel, MIX_DMA_SEL);
354 /* re-read to verify */
355 tmp = read_mix(MIX_DMA_SEL);
366 #define V(maj, min) (((maj) << 8) | (min))
368 static const char *sbname(int ver)
370 int major = VER_MAJOR(ver);
371 int minor = VER_MINOR(ver);
376 return "Sound Blaster 1.5";
378 return "Sound Blaster 1.0";
381 if(minor == 1 || minor == 2) {
382 return "Sound Blaster 2.0";
389 return "Sound Blaster Pro";
392 return "Sound Blaster Pro 2";
394 return "Gallant SC-6000";
404 return "Sound Blaster 16";
406 return "Sound Blaster 16 SCSI-2";
408 return "Sound Blaster AWE 32";
410 return "Sound Blaster ViBRA16C";
412 return "Sound Blaster AWE 64";
419 return "Unknown Sound Blaster";