1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * pcm emulation on emu8000 wavetable
4 *
5 * Copyright (C) 2002 Takashi Iwai <tiwai@suse.de>
6 */
7
8#include "emu8000_local.h"
9
10#include <linux/sched/signal.h>
11#include <linux/init.h>
12#include <linux/slab.h>
13#include <sound/initval.h>
14#include <sound/pcm.h>
15
16/*
17 * define the following if you want to use this pcm with non-interleaved mode
18 */
19/* #define USE_NONINTERLEAVE */
20
21/* NOTE: for using the non-interleaved mode with alsa-lib, you have to set
22 * mmap_emulation flag to 1 in your .asoundrc, such like
23 *
24 * pcm.emu8k {
25 * type plug
26 * slave.pcm {
27 * type hw
28 * card 0
29 * device 1
30 * mmap_emulation 1
31 * }
32 * }
33 *
34 * besides, for the time being, the non-interleaved mode doesn't work well on
35 * alsa-lib...
36 */
37
38
39struct snd_emu8k_pcm {
40 struct snd_emu8000 *emu;
41 struct snd_pcm_substream *substream;
42
43 unsigned int allocated_bytes;
44 struct snd_util_memblk *block;
45 unsigned int offset;
46 unsigned int buf_size;
47 unsigned int period_size;
48 unsigned int loop_start[2];
49 unsigned int pitch;
50 int panning[2];
51 int last_ptr;
52 int period_pos;
53 int voices;
54 unsigned int dram_opened: 1;
55 unsigned int running: 1;
56 unsigned int timer_running: 1;
57 struct timer_list timer;
58 spinlock_t timer_lock;
59};
60
61#define LOOP_BLANK_SIZE 8
62
63
64/*
65 * open up channels for the simultaneous data transfer and playback
66 */
67static int
68emu8k_open_dram_for_pcm(struct snd_emu8000 *emu, int channels)
69{
70 int i;
71
72 /* reserve up to 2 voices for playback */
73 snd_emux_lock_voice(emu: emu->emu, voice: 0);
74 if (channels > 1)
75 snd_emux_lock_voice(emu: emu->emu, voice: 1);
76
77 /* reserve 28 voices for loading */
78 for (i = channels + 1; i < EMU8000_DRAM_VOICES; i++) {
79 unsigned int mode = EMU8000_RAM_WRITE;
80 snd_emux_lock_voice(emu: emu->emu, voice: i);
81#ifndef USE_NONINTERLEAVE
82 if (channels > 1 && (i & 1) != 0)
83 mode |= EMU8000_RAM_RIGHT;
84#endif
85 snd_emu8000_dma_chan(emu, ch: i, mode);
86 }
87
88 /* assign voice 31 and 32 to ROM */
89 EMU8000_VTFT_WRITE(emu, 30, 0);
90 EMU8000_PSST_WRITE(emu, 30, 0x1d8);
91 EMU8000_CSL_WRITE(emu, 30, 0x1e0);
92 EMU8000_CCCA_WRITE(emu, 30, 0x1d8);
93 EMU8000_VTFT_WRITE(emu, 31, 0);
94 EMU8000_PSST_WRITE(emu, 31, 0x1d8);
95 EMU8000_CSL_WRITE(emu, 31, 0x1e0);
96 EMU8000_CCCA_WRITE(emu, 31, 0x1d8);
97
98 return 0;
99}
100
101/*
102 */
103static void
104snd_emu8000_write_wait(struct snd_emu8000 *emu, int can_schedule)
105{
106 while ((EMU8000_SMALW_READ(emu) & 0x80000000) != 0) {
107 if (can_schedule) {
108 schedule_timeout_interruptible(timeout: 1);
109 if (signal_pending(current))
110 break;
111 }
112 }
113}
114
115/*
116 * close all channels
117 */
118static void
119emu8k_close_dram(struct snd_emu8000 *emu)
120{
121 int i;
122
123 for (i = 0; i < 2; i++)
124 snd_emux_unlock_voice(emu: emu->emu, voice: i);
125 for (; i < EMU8000_DRAM_VOICES; i++) {
126 snd_emu8000_dma_chan(emu, ch: i, EMU8000_RAM_CLOSE);
127 snd_emux_unlock_voice(emu: emu->emu, voice: i);
128 }
129}
130
131/*
132 * convert Hz to AWE32 rate offset (see emux/soundfont.c)
133 */
134
135#define OFFSET_SAMPLERATE 1011119 /* base = 44100 */
136#define SAMPLERATE_RATIO 4096
137
138static int calc_rate_offset(int hz)
139{
140 return snd_sf_linear_to_log(amount: hz, OFFSET_SAMPLERATE, SAMPLERATE_RATIO);
141}
142
143
144/*
145 */
146
147static const struct snd_pcm_hardware emu8k_pcm_hw = {
148#ifdef USE_NONINTERLEAVE
149 .info = SNDRV_PCM_INFO_NONINTERLEAVED,
150#else
151 .info = SNDRV_PCM_INFO_INTERLEAVED,
152#endif
153 .formats = SNDRV_PCM_FMTBIT_S16_LE,
154 .rates = SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
155 .rate_min = 4000,
156 .rate_max = 48000,
157 .channels_min = 1,
158 .channels_max = 2,
159 .buffer_bytes_max = (128*1024),
160 .period_bytes_min = 1024,
161 .period_bytes_max = (128*1024),
162 .periods_min = 2,
163 .periods_max = 1024,
164 .fifo_size = 0,
165
166};
167
168/*
169 * get the current position at the given channel from CCCA register
170 */
171static inline int emu8k_get_curpos(struct snd_emu8k_pcm *rec, int ch)
172{
173 int val = EMU8000_CCCA_READ(rec->emu, ch) & 0xfffffff;
174 val -= rec->loop_start[ch] - 1;
175 return val;
176}
177
178
179/*
180 * timer interrupt handler
181 * check the current position and update the period if necessary.
182 */
183static void emu8k_pcm_timer_func(struct timer_list *t)
184{
185 struct snd_emu8k_pcm *rec = from_timer(rec, t, timer);
186 int ptr, delta;
187
188 spin_lock(lock: &rec->timer_lock);
189 /* update the current pointer */
190 ptr = emu8k_get_curpos(rec, ch: 0);
191 if (ptr < rec->last_ptr)
192 delta = ptr + rec->buf_size - rec->last_ptr;
193 else
194 delta = ptr - rec->last_ptr;
195 rec->period_pos += delta;
196 rec->last_ptr = ptr;
197
198 /* reprogram timer */
199 mod_timer(timer: &rec->timer, expires: jiffies + 1);
200
201 /* update period */
202 if (rec->period_pos >= (int)rec->period_size) {
203 rec->period_pos %= rec->period_size;
204 spin_unlock(lock: &rec->timer_lock);
205 snd_pcm_period_elapsed(substream: rec->substream);
206 return;
207 }
208 spin_unlock(lock: &rec->timer_lock);
209}
210
211
212/*
213 * open pcm
214 * creating an instance here
215 */
216static int emu8k_pcm_open(struct snd_pcm_substream *subs)
217{
218 struct snd_emu8000 *emu = snd_pcm_substream_chip(subs);
219 struct snd_emu8k_pcm *rec;
220 struct snd_pcm_runtime *runtime = subs->runtime;
221
222 rec = kzalloc(size: sizeof(*rec), GFP_KERNEL);
223 if (! rec)
224 return -ENOMEM;
225
226 rec->emu = emu;
227 rec->substream = subs;
228 runtime->private_data = rec;
229
230 spin_lock_init(&rec->timer_lock);
231 timer_setup(&rec->timer, emu8k_pcm_timer_func, 0);
232
233 runtime->hw = emu8k_pcm_hw;
234 runtime->hw.buffer_bytes_max = emu->mem_size - LOOP_BLANK_SIZE * 3;
235 runtime->hw.period_bytes_max = runtime->hw.buffer_bytes_max / 2;
236
237 /* use timer to update periods.. (specified in msec) */
238 snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
239 DIV_ROUND_UP(1000000, HZ), UINT_MAX);
240
241 return 0;
242}
243
244static int emu8k_pcm_close(struct snd_pcm_substream *subs)
245{
246 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
247 kfree(objp: rec);
248 subs->runtime->private_data = NULL;
249 return 0;
250}
251
252/*
253 * calculate pitch target
254 */
255static int calc_pitch_target(int pitch)
256{
257 int ptarget = 1 << (pitch >> 12);
258 if (pitch & 0x800) ptarget += (ptarget * 0x102e) / 0x2710;
259 if (pitch & 0x400) ptarget += (ptarget * 0x764) / 0x2710;
260 if (pitch & 0x200) ptarget += (ptarget * 0x389) / 0x2710;
261 ptarget += (ptarget >> 1);
262 if (ptarget > 0xffff) ptarget = 0xffff;
263 return ptarget;
264}
265
266/*
267 * set up the voice
268 */
269static void setup_voice(struct snd_emu8k_pcm *rec, int ch)
270{
271 struct snd_emu8000 *hw = rec->emu;
272 unsigned int temp;
273
274 /* channel to be silent and idle */
275 EMU8000_DCYSUSV_WRITE(hw, ch, 0x0080);
276 EMU8000_VTFT_WRITE(hw, ch, 0x0000FFFF);
277 EMU8000_CVCF_WRITE(hw, ch, 0x0000FFFF);
278 EMU8000_PTRX_WRITE(hw, ch, 0);
279 EMU8000_CPF_WRITE(hw, ch, 0);
280
281 /* pitch offset */
282 EMU8000_IP_WRITE(hw, ch, rec->pitch);
283 /* set envelope parameters */
284 EMU8000_ENVVAL_WRITE(hw, ch, 0x8000);
285 EMU8000_ATKHLD_WRITE(hw, ch, 0x7f7f);
286 EMU8000_DCYSUS_WRITE(hw, ch, 0x7f7f);
287 EMU8000_ENVVOL_WRITE(hw, ch, 0x8000);
288 EMU8000_ATKHLDV_WRITE(hw, ch, 0x7f7f);
289 /* decay/sustain parameter for volume envelope is used
290 for triggerg the voice */
291 /* modulation envelope heights */
292 EMU8000_PEFE_WRITE(hw, ch, 0x0);
293 /* lfo1/2 delay */
294 EMU8000_LFO1VAL_WRITE(hw, ch, 0x8000);
295 EMU8000_LFO2VAL_WRITE(hw, ch, 0x8000);
296 /* lfo1 pitch & cutoff shift */
297 EMU8000_FMMOD_WRITE(hw, ch, 0);
298 /* lfo1 volume & freq */
299 EMU8000_TREMFRQ_WRITE(hw, ch, 0);
300 /* lfo2 pitch & freq */
301 EMU8000_FM2FRQ2_WRITE(hw, ch, 0);
302 /* pan & loop start */
303 temp = rec->panning[ch];
304 temp = (temp <<24) | ((unsigned int)rec->loop_start[ch] - 1);
305 EMU8000_PSST_WRITE(hw, ch, temp);
306 /* chorus & loop end (chorus 8bit, MSB) */
307 temp = 0; // chorus
308 temp = (temp << 24) | ((unsigned int)rec->loop_start[ch] + rec->buf_size - 1);
309 EMU8000_CSL_WRITE(hw, ch, temp);
310 /* Q & current address (Q 4bit value, MSB) */
311 temp = 0; // filterQ
312 temp = (temp << 28) | ((unsigned int)rec->loop_start[ch] - 1);
313 EMU8000_CCCA_WRITE(hw, ch, temp);
314 /* clear unknown registers */
315 EMU8000_00A0_WRITE(hw, ch, 0);
316 EMU8000_0080_WRITE(hw, ch, 0);
317}
318
319/*
320 * trigger the voice
321 */
322static void start_voice(struct snd_emu8k_pcm *rec, int ch)
323{
324 unsigned long flags;
325 struct snd_emu8000 *hw = rec->emu;
326 unsigned int temp, aux;
327 int pt = calc_pitch_target(pitch: rec->pitch);
328
329 /* cutoff and volume */
330 EMU8000_IFATN_WRITE(hw, ch, 0xff00);
331 EMU8000_VTFT_WRITE(hw, ch, 0xffff);
332 EMU8000_CVCF_WRITE(hw, ch, 0xffff);
333 /* trigger envelope */
334 EMU8000_DCYSUSV_WRITE(hw, ch, 0x7f7f);
335 /* set reverb and pitch target */
336 temp = 0; // reverb
337 if (rec->panning[ch] == 0)
338 aux = 0xff;
339 else
340 aux = (-rec->panning[ch]) & 0xff;
341 temp = (temp << 8) | (pt << 16) | aux;
342 EMU8000_PTRX_WRITE(hw, ch, temp);
343 EMU8000_CPF_WRITE(hw, ch, pt << 16);
344
345 /* start timer */
346 spin_lock_irqsave(&rec->timer_lock, flags);
347 if (! rec->timer_running) {
348 mod_timer(timer: &rec->timer, expires: jiffies + 1);
349 rec->timer_running = 1;
350 }
351 spin_unlock_irqrestore(lock: &rec->timer_lock, flags);
352}
353
354/*
355 * stop the voice immediately
356 */
357static void stop_voice(struct snd_emu8k_pcm *rec, int ch)
358{
359 unsigned long flags;
360 struct snd_emu8000 *hw = rec->emu;
361
362 EMU8000_DCYSUSV_WRITE(hw, ch, 0x807F);
363
364 /* stop timer */
365 spin_lock_irqsave(&rec->timer_lock, flags);
366 if (rec->timer_running) {
367 del_timer(timer: &rec->timer);
368 rec->timer_running = 0;
369 }
370 spin_unlock_irqrestore(lock: &rec->timer_lock, flags);
371}
372
373static int emu8k_pcm_trigger(struct snd_pcm_substream *subs, int cmd)
374{
375 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
376 int ch;
377
378 switch (cmd) {
379 case SNDRV_PCM_TRIGGER_START:
380 for (ch = 0; ch < rec->voices; ch++)
381 start_voice(rec, ch);
382 rec->running = 1;
383 break;
384 case SNDRV_PCM_TRIGGER_STOP:
385 rec->running = 0;
386 for (ch = 0; ch < rec->voices; ch++)
387 stop_voice(rec, ch);
388 break;
389 default:
390 return -EINVAL;
391 }
392 return 0;
393}
394
395
396/*
397 * copy / silence ops
398 */
399
400/*
401 * this macro should be inserted in the copy/silence loops
402 * to reduce the latency. without this, the system will hang up
403 * during the whole loop.
404 */
405#define CHECK_SCHEDULER() \
406do { \
407 cond_resched();\
408 if (signal_pending(current))\
409 return -EAGAIN;\
410} while (0)
411
412#define GET_VAL(sval, iter) \
413 do { \
414 if (!iter) \
415 sval = 0; \
416 else if (copy_from_iter(&sval, 2, iter) != 2) \
417 return -EFAULT; \
418 } while (0)
419
420#ifdef USE_NONINTERLEAVE
421
422#define LOOP_WRITE(rec, offset, iter, count) \
423 do { \
424 struct snd_emu8000 *emu = (rec)->emu; \
425 snd_emu8000_write_wait(emu, 1); \
426 EMU8000_SMALW_WRITE(emu, offset); \
427 while (count > 0) { \
428 unsigned short sval; \
429 CHECK_SCHEDULER(); \
430 GET_VAL(sval, iter); \
431 EMU8000_SMLD_WRITE(emu, sval); \
432 count--; \
433 } \
434 } while (0)
435
436/* copy one channel block */
437static int emu8k_pcm_copy(struct snd_pcm_substream *subs,
438 int voice, unsigned long pos,
439 struct iov_iter *src, unsigned long count)
440{
441 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
442
443 /* convert to word unit */
444 pos = (pos << 1) + rec->loop_start[voice];
445 count <<= 1;
446 LOOP_WRITE(rec, pos, src, count);
447 return 0;
448}
449
450/* make a channel block silence */
451static int emu8k_pcm_silence(struct snd_pcm_substream *subs,
452 int voice, unsigned long pos, unsigned long count)
453{
454 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
455
456 /* convert to word unit */
457 pos = (pos << 1) + rec->loop_start[voice];
458 count <<= 1;
459 LOOP_WRITE(rec, pos, NULL, count);
460 return 0;
461}
462
463#else /* interleave */
464
465#define LOOP_WRITE(rec, pos, iter, count) \
466 do { \
467 struct snd_emu8000 *emu = rec->emu; \
468 snd_emu8000_write_wait(emu, 1); \
469 EMU8000_SMALW_WRITE(emu, pos + rec->loop_start[0]); \
470 if (rec->voices > 1) \
471 EMU8000_SMARW_WRITE(emu, pos + rec->loop_start[1]); \
472 while (count > 0) { \
473 unsigned short sval; \
474 CHECK_SCHEDULER(); \
475 GET_VAL(sval, iter); \
476 EMU8000_SMLD_WRITE(emu, sval); \
477 if (rec->voices > 1) { \
478 CHECK_SCHEDULER(); \
479 GET_VAL(sval, iter); \
480 EMU8000_SMRD_WRITE(emu, sval); \
481 } \
482 count--; \
483 } \
484 } while (0)
485
486
487/*
488 * copy the interleaved data can be done easily by using
489 * DMA "left" and "right" channels on emu8k engine.
490 */
491static int emu8k_pcm_copy(struct snd_pcm_substream *subs,
492 int voice, unsigned long pos,
493 struct iov_iter *src, unsigned long count)
494{
495 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
496
497 /* convert to frames */
498 pos = bytes_to_frames(runtime: subs->runtime, size: pos);
499 count = bytes_to_frames(runtime: subs->runtime, size: count);
500 LOOP_WRITE(rec, pos, src, count);
501 return 0;
502}
503
504static int emu8k_pcm_silence(struct snd_pcm_substream *subs,
505 int voice, unsigned long pos, unsigned long count)
506{
507 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
508
509 /* convert to frames */
510 pos = bytes_to_frames(runtime: subs->runtime, size: pos);
511 count = bytes_to_frames(runtime: subs->runtime, size: count);
512 LOOP_WRITE(rec, pos, NULL, count);
513 return 0;
514}
515#endif
516
517
518/*
519 * allocate a memory block
520 */
521static int emu8k_pcm_hw_params(struct snd_pcm_substream *subs,
522 struct snd_pcm_hw_params *hw_params)
523{
524 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
525
526 if (rec->block) {
527 /* reallocation - release the old block */
528 snd_util_mem_free(hdr: rec->emu->memhdr, blk: rec->block);
529 rec->block = NULL;
530 }
531
532 rec->allocated_bytes = params_buffer_bytes(p: hw_params) + LOOP_BLANK_SIZE * 4;
533 rec->block = snd_util_mem_alloc(hdr: rec->emu->memhdr, size: rec->allocated_bytes);
534 if (! rec->block)
535 return -ENOMEM;
536 rec->offset = EMU8000_DRAM_OFFSET + (rec->block->offset >> 1); /* in word */
537 /* at least dma_bytes must be set for non-interleaved mode */
538 subs->dma_buffer.bytes = params_buffer_bytes(p: hw_params);
539
540 return 0;
541}
542
543/*
544 * free the memory block
545 */
546static int emu8k_pcm_hw_free(struct snd_pcm_substream *subs)
547{
548 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
549
550 if (rec->block) {
551 int ch;
552 for (ch = 0; ch < rec->voices; ch++)
553 stop_voice(rec, ch); // to be sure
554 if (rec->dram_opened)
555 emu8k_close_dram(emu: rec->emu);
556 snd_util_mem_free(hdr: rec->emu->memhdr, blk: rec->block);
557 rec->block = NULL;
558 }
559 return 0;
560}
561
562/*
563 */
564static int emu8k_pcm_prepare(struct snd_pcm_substream *subs)
565{
566 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
567
568 rec->pitch = 0xe000 + calc_rate_offset(hz: subs->runtime->rate);
569 rec->last_ptr = 0;
570 rec->period_pos = 0;
571
572 rec->buf_size = subs->runtime->buffer_size;
573 rec->period_size = subs->runtime->period_size;
574 rec->voices = subs->runtime->channels;
575 rec->loop_start[0] = rec->offset + LOOP_BLANK_SIZE;
576 if (rec->voices > 1)
577 rec->loop_start[1] = rec->loop_start[0] + rec->buf_size + LOOP_BLANK_SIZE;
578 if (rec->voices > 1) {
579 rec->panning[0] = 0xff;
580 rec->panning[1] = 0x00;
581 } else
582 rec->panning[0] = 0x80;
583
584 if (! rec->dram_opened) {
585 int err, i, ch;
586
587 snd_emux_terminate_all(emu: rec->emu->emu);
588 err = emu8k_open_dram_for_pcm(emu: rec->emu, channels: rec->voices);
589 if (err)
590 return err;
591 rec->dram_opened = 1;
592
593 /* clear loop blanks */
594 snd_emu8000_write_wait(emu: rec->emu, can_schedule: 0);
595 EMU8000_SMALW_WRITE(rec->emu, rec->offset);
596 for (i = 0; i < LOOP_BLANK_SIZE; i++)
597 EMU8000_SMLD_WRITE(rec->emu, 0);
598 for (ch = 0; ch < rec->voices; ch++) {
599 EMU8000_SMALW_WRITE(rec->emu, rec->loop_start[ch] + rec->buf_size);
600 for (i = 0; i < LOOP_BLANK_SIZE; i++)
601 EMU8000_SMLD_WRITE(rec->emu, 0);
602 }
603 }
604
605 setup_voice(rec, ch: 0);
606 if (rec->voices > 1)
607 setup_voice(rec, ch: 1);
608 return 0;
609}
610
611static snd_pcm_uframes_t emu8k_pcm_pointer(struct snd_pcm_substream *subs)
612{
613 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
614 if (rec->running)
615 return emu8k_get_curpos(rec, ch: 0);
616 return 0;
617}
618
619
620static const struct snd_pcm_ops emu8k_pcm_ops = {
621 .open = emu8k_pcm_open,
622 .close = emu8k_pcm_close,
623 .hw_params = emu8k_pcm_hw_params,
624 .hw_free = emu8k_pcm_hw_free,
625 .prepare = emu8k_pcm_prepare,
626 .trigger = emu8k_pcm_trigger,
627 .pointer = emu8k_pcm_pointer,
628 .copy = emu8k_pcm_copy,
629 .fill_silence = emu8k_pcm_silence,
630};
631
632
633static void snd_emu8000_pcm_free(struct snd_pcm *pcm)
634{
635 struct snd_emu8000 *emu = pcm->private_data;
636 emu->pcm = NULL;
637}
638
639int snd_emu8000_pcm_new(struct snd_card *card, struct snd_emu8000 *emu, int index)
640{
641 struct snd_pcm *pcm;
642 int err;
643
644 err = snd_pcm_new(card, id: "Emu8000 PCM", device: index, playback_count: 1, capture_count: 0, rpcm: &pcm);
645 if (err < 0)
646 return err;
647 pcm->private_data = emu;
648 pcm->private_free = snd_emu8000_pcm_free;
649 snd_pcm_set_ops(pcm, direction: SNDRV_PCM_STREAM_PLAYBACK, ops: &emu8k_pcm_ops);
650 emu->pcm = pcm;
651
652 snd_device_register(card, device_data: pcm);
653
654 return 0;
655}
656

source code of linux/sound/isa/sb/emu8000_pcm.c