// SPDX-License-Identifier: GPL-2.0-or-later
/*
* pcm emulation on emu8000 wavetable
*
* Copyright (C) 2002 Takashi Iwai <[email protected]>
*/
#include "emu8000_local.h"
#include <linux/sched/signal.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <sound/initval.h>
#include <sound/pcm.h>
/*
* define the following if you want to use this pcm with non-interleaved mode
*/
/* #define USE_NONINTERLEAVE */
/* NOTE: for using the non-interleaved mode with alsa-lib, you have to set
* mmap_emulation flag to 1 in your .asoundrc, such like
*
* pcm.emu8k {
* type plug
* slave.pcm {
* type hw
* card 0
* device 1
* mmap_emulation 1
* }
* }
*
* besides, for the time being, the non-interleaved mode doesn't work well on
* alsa-lib...
*/
struct snd_emu8k_pcm {
struct snd_emu8000 *emu;
struct snd_pcm_substream *substream;
unsigned int allocated_bytes;
struct snd_util_memblk *block;
unsigned int offset;
unsigned int buf_size;
unsigned int period_size;
unsigned int loop_start[2];
unsigned int pitch;
int panning[2];
int last_ptr;
int period_pos;
int voices;
unsigned int dram_opened: 1;
unsigned int running: 1;
unsigned int timer_running: 1;
struct timer_list timer;
spinlock_t timer_lock;
};
#define LOOP_BLANK_SIZE 8
/*
* open up channels for the simultaneous data transfer and playback
*/
static int
emu8k_open_dram_for_pcm(struct snd_emu8000 *emu, int channels)
{
int i;
/* reserve up to 2 voices for playback */
snd_emux_lock_voice(emu->emu, 0);
if (channels > 1)
snd_emux_lock_voice(emu->emu, 1);
/* reserve 28 voices for loading */
for (i = channels + 1; i < EMU8000_DRAM_VOICES; i++) {
unsigned int mode = EMU8000_RAM_WRITE;
snd_emux_lock_voice(emu->emu, i);
#ifndef USE_NONINTERLEAVE
if (channels > 1 && (i & 1) != 0)
mode |= EMU8000_RAM_RIGHT;
#endif
snd_emu8000_dma_chan(emu, i, mode);
}
/* assign voice 31 and 32 to ROM */
EMU8000_VTFT_WRITE(emu, 30, 0);
EMU8000_PSST_WRITE(emu, 30, 0x1d8);
EMU8000_CSL_WRITE(emu, 30, 0x1e0);
EMU8000_CCCA_WRITE(emu, 30, 0x1d8);
EMU8000_VTFT_WRITE(emu, 31, 0);
EMU8000_PSST_WRITE(emu, 31, 0x1d8);
EMU8000_CSL_WRITE(emu, 31, 0x1e0);
EMU8000_CCCA_WRITE(emu, 31, 0x1d8);
return 0;
}
/*
*/
static void
snd_emu8000_write_wait(struct snd_emu8000 *emu, int can_schedule)
{
while ((EMU8000_SMALW_READ(emu) & 0x80000000) != 0) {
if (can_schedule) {
schedule_timeout_interruptible(1);
if (signal_pending(current))
break;
}
}
}
/*
* close all channels
*/
static void
emu8k_close_dram(struct snd_emu8000 *emu)
{
int i;
for (i = 0; i < 2; i++)
snd_emux_unlock_voice(emu->emu, i);
for (; i < EMU8000_DRAM_VOICES; i++) {
snd_emu8000_dma_chan(emu, i, EMU8000_RAM_CLOSE);
snd_emux_unlock_voice(emu->emu, i);
}
}
/*
* convert Hz to AWE32 rate offset (see emux/soundfont.c)
*/
#define OFFSET_SAMPLERATE 1011119 /* base = 44100 */
#define SAMPLERATE_RATIO 4096
static int calc_rate_offset(int hz)
{
return snd_sf_linear_to_log(hz, OFFSET_SAMPLERATE, SAMPLERATE_RATIO);
}
/*
*/
static const struct snd_pcm_hardware emu8k_pcm_hw = {
#ifdef USE_NONINTERLEAVE
.info = SNDRV_PCM_INFO_NONINTERLEAVED,
#else
.info = SNDRV_PCM_INFO_INTERLEAVED,
#endif
.formats = SNDRV_PCM_FMTBIT_S16_LE,
.rates = SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
.rate_min = 4000,
.rate_max = 48000,
.channels_min = 1,
.channels_max = 2,
.buffer_bytes_max = (128*1024),
.period_bytes_min = 1024,
.period_bytes_max = (128*1024),
.periods_min = 2,
.periods_max = 1024,
.fifo_size = 0,
};
/*
* get the current position at the given channel from CCCA register
*/
static inline int emu8k_get_curpos(struct snd_emu8k_pcm *rec, int ch)
{
int val = EMU8000_CCCA_READ(rec->emu, ch) & 0xfffffff;
val -= rec->loop_start[ch] - 1;
return val;
}
/*
* timer interrupt handler
* check the current position and update the period if necessary.
*/
static void emu8k_pcm_timer_func(struct timer_list *t)
{
struct snd_emu8k_pcm *rec = from_timer(rec, t, timer);
int ptr, delta;
spin_lock(&rec->timer_lock);
/* update the current pointer */
ptr = emu8k_get_curpos(rec, 0);
if (ptr < rec->last_ptr)
delta = ptr + rec->buf_size - rec->last_ptr;
else
delta = ptr - rec->last_ptr;
rec->period_pos += delta;
rec->last_ptr = ptr;
/* reprogram timer */
mod_timer(&rec->timer, jiffies + 1);
/* update period */
if (rec->period_pos >= (int)rec->period_size) {
rec->period_pos %= rec->period_size;
spin_unlock(&rec->timer_lock);
snd_pcm_period_elapsed(rec->substream);
return;
}
spin_unlock(&rec->timer_lock);
}
/*
* open pcm
* creating an instance here
*/
static int emu8k_pcm_open(struct snd_pcm_substream *subs)
{
struct snd_emu8000 *emu = snd_pcm_substream_chip(subs);
struct snd_emu8k_pcm *rec;
struct snd_pcm_runtime *runtime = subs->runtime;
rec = kzalloc(sizeof(*rec), GFP_KERNEL);
if (! rec)
return -ENOMEM;
rec->emu = emu;
rec->substream = subs;
runtime->private_data = rec;
spin_lock_init(&rec->timer_lock);
timer_setup(&rec->timer, emu8k_pcm_timer_func, 0);
runtime->hw = emu8k_pcm_hw;
runtime->hw.buffer_bytes_max = emu->mem_size - LOOP_BLANK_SIZE * 3;
runtime->hw.period_bytes_max = runtime->hw.buffer_bytes_max / 2;
/* use timer to update periods.. (specified in msec) */
snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
DIV_ROUND_UP(1000000, HZ), UINT_MAX);
return 0;
}
static int emu8k_pcm_close(struct snd_pcm_substream *subs)
{
struct snd_emu8k_pcm *rec = subs->runtime->private_data;
kfree(rec);
subs->runtime->private_data = NULL;
return 0;
}
/*
* calculate pitch target
*/
static int calc_pitch_target(int pitch)
{
int ptarget = 1 << (pitch >> 12);
if (pitch & 0x800) ptarget += (ptarget * 0x102e) / 0x2710;
if (pitch & 0x400) ptarget += (ptarget * 0x764) / 0x2710;
if (pitch & 0x200) ptarget += (ptarget * 0x389) / 0x2710;
ptarget += (ptarget >> 1);
if (ptarget > 0xffff) ptarget = 0xffff;
return ptarget;
}
/*
* set up the voice
*/
static void setup_voice(struct snd_emu8k_pcm *rec, int ch)
{
struct snd_emu8000 *hw = rec->emu;
unsigned int temp;
/* channel to be silent and idle */
EMU8000_DCYSUSV_WRITE(hw, ch, 0x0080);
EMU8000_VTFT_WRITE(hw, ch, 0x0000FFFF);
EMU8000_CVCF_WRITE(hw, ch, 0x0000FFFF);
EMU8000_PTRX_WRITE(hw, ch, 0);
EMU8000_CPF_WRITE(hw, ch, 0);
/* pitch offset */
EMU8000_IP_WRITE(hw, ch, rec->pitch);
/* set envelope parameters */
EMU8000_ENVVAL_WRITE(hw, ch, 0x8000);
EMU8000_ATKHLD_WRITE(hw, ch, 0x7f7f);
EMU8000_DCYSUS_WRITE(hw, ch, 0x7f7f);
EMU8000_ENVVOL_WRITE(hw, ch, 0x8000);
EMU8000_ATKHLDV_WRITE(hw, ch, 0x7f7f);
/* decay/sustain parameter for volume envelope is used
for triggerg the voice */
/* modulation envelope heights */
EMU8000_PEFE_WRITE(hw, ch, 0x0);
/* lfo1/2 delay */
EMU8000_LFO1VAL_WRITE(hw, ch, 0x8000);
EMU8000_LFO2VAL_WRITE(hw, ch, 0x8000);
/* lfo1 pitch & cutoff shift */
EMU8000_FMMOD_WRITE(hw, ch, 0);
/* lfo1 volume & freq */
EMU8000_TREMFRQ_WRITE(hw, ch, 0);
/* lfo2 pitch & freq */
EMU8000_FM2FRQ2_WRITE(hw, ch, 0);
/* pan & loop start */
temp = rec->panning[ch];
temp = (temp <<24) | ((unsigned int)rec->loop_start[ch] - 1);
EMU8000_PSST_WRITE(hw, ch, temp);
/* chorus & loop end (chorus 8bit, MSB) */
temp = 0; // chorus
temp = (temp << 24) | ((unsigned int)rec->loop_start[ch] + rec->buf_size - 1);
EMU8000_CSL_WRITE(hw, ch, temp);
/* Q & current address (Q 4bit value, MSB) */
temp = 0; // filterQ
temp = (temp << 28) | ((unsigned int)rec->loop_start[ch] - 1);
EMU8000_CCCA_WRITE(hw, ch, temp);
/* clear unknown registers */
EMU8000_00A0_WRITE(hw, ch, 0);
EMU8000_0080_WRITE(hw, ch, 0);
}
/*
* trigger the voice
*/
static void start_voice(struct snd_emu8k_pcm *rec, int ch)
{
unsigned long flags;
struct snd_emu8000 *hw = rec->emu;
unsigned int temp, aux;
int pt = calc_pitch_target(rec->pitch);
/* cutoff and volume */
EMU8000_IFATN_WRITE(hw, ch, 0xff00);
EMU8000_VTFT_WRITE(hw, ch, 0xffff);
EMU8000_CVCF_WRITE(hw, ch, 0xffff);
/* trigger envelope */
EMU8000_DCYSUSV_WRITE(hw, ch, 0x7f7f);
/* set reverb and pitch target */
temp = 0; // reverb
if (rec->panning[ch] == 0)
aux = 0xff;
else
aux = (-rec->panning[ch]) & 0xff;
temp = (temp << 8) | (pt << 16) | aux;
EMU8000_PTRX_WRITE(hw, ch, temp);
EMU8000_CPF_WRITE(hw, ch, pt << 16);
/* start timer */
spin_lock_irqsave(&rec->timer_lock, flags);
if (! rec->timer_running) {
mod_timer(&rec->timer, jiffies + 1);
rec->timer_running = 1;
}
spin_unlock_irqrestore(&rec->timer_lock, flags);
}
/*
* stop the voice immediately
*/
static void stop_voice(struct snd_emu8k_pcm *rec, int ch)
{
unsigned long flags;
struct snd_emu8000 *hw = rec->emu;
EMU8000_DCYSUSV_WRITE(hw, ch, 0x807F);
/* stop timer */
spin_lock_irqsave(&rec->timer_lock, flags);
if (rec->timer_running) {
del_timer(&rec->timer);
rec->timer_running = 0;
}
spin_unlock_irqrestore(&rec->timer_lock, flags);
}
static int emu8k_pcm_trigger(struct snd_pcm_substream *subs, int cmd)
{
struct snd_emu8k_pcm *rec = subs->runtime->private_data;
int ch;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
for (ch = 0; ch < rec->voices; ch++)
start_voice(rec, ch);
rec->running = 1;
break;
case SNDRV_PCM_TRIGGER_STOP:
rec->running = 0;
for (ch = 0; ch < rec->voices; ch++)
stop_voice(rec, ch);
break;
default:
return -EINVAL;
}
return 0;
}
/*
* copy / silence ops
*/
/*
* this macro should be inserted in the copy/silence loops
* to reduce the latency. without this, the system will hang up
* during the whole loop.
*/
#define CHECK_SCHEDULER() \
do { \
cond_resched();\
if (signal_pending(current))\
return -EAGAIN;\
} while (0)
#define GET_VAL(sval, iter) \
do { \
if (!iter) \
sval = 0; \
else if (copy_from_iter(&sval, 2, iter) != 2) \
return -EFAULT; \
} while (0)
#ifdef USE_NONINTERLEAVE
#define LOOP_WRITE(rec, offset, iter, count) \
do { \
struct snd_emu8000 *emu = (rec)->emu; \
snd_emu8000_write_wait(emu, 1); \
EMU8000_SMALW_WRITE(emu, offset); \
while (count > 0) { \
unsigned short sval; \
CHECK_SCHEDULER(); \
GET_VAL(sval, iter); \
EMU8000_SMLD_WRITE(emu, sval); \
count--; \
} \
} while (0)
/* copy one channel block */
static int emu8k_pcm_copy(struct snd_pcm_substream *subs,
int voice, unsigned long pos,
struct iov_iter *src, unsigned long count)
{
struct snd_emu8k_pcm *rec = subs->runtime->private_data;
/* convert to word unit */
pos = (pos << 1) + rec->loop_start[voice];
count <<= 1;
LOOP_WRITE(rec, pos, src, count);
return 0;
}
/* make a channel block silence */
static int emu8k_pcm_silence(struct snd_pcm_substream *subs,
int voice, unsigned long pos, unsigned long count)
{
struct snd_emu8k_pcm *rec = subs->runtime->private_data;
/* convert to word unit */
pos = (pos << 1) + rec->loop_start[voice];
count <<= 1;
LOOP_WRITE(rec, pos, NULL, count);
return 0;
}
#else /* interleave */
#define LOOP_WRITE(rec, pos, iter, count) \
do { \
struct snd_emu8000 *emu = rec->emu; \
snd_emu8000_write_wait(emu, 1); \
EMU8000_SMALW_WRITE(emu, pos + rec->loop_start[0]); \
if (rec->voices > 1) \
EMU8000_SMARW_WRITE(emu, pos + rec->loop_start[1]); \
while (count > 0) { \
unsigned short sval; \
CHECK_SCHEDULER(); \
GET_VAL(sval, iter); \
EMU8000_SMLD_WRITE(emu, sval); \
if (rec->voices > 1) { \
CHECK_SCHEDULER(); \
GET_VAL(sval, iter); \
EMU8000_SMRD_WRITE(emu, sval); \
} \
count--; \
} \
} while (0)
/*
* copy the interleaved data can be done easily by using
* DMA "left" and "right" channels on emu8k engine.
*/
static int emu8k_pcm_copy(struct snd_pcm_substream *subs,
int voice, unsigned long pos,
struct iov_iter *src, unsigned long count)
{
struct snd_emu8k_pcm *rec = subs->runtime->private_data;
/* convert to frames */
pos = bytes_to_frames(subs->runtime, pos);
count = bytes_to_frames(subs->runtime, count);
LOOP_WRITE(rec, pos, src, count);
return 0;
}
static int emu8k_pcm_silence(struct snd_pcm_substream *subs,
int voice, unsigned long pos, unsigned long count)
{
struct snd_emu8k_pcm *rec = subs->runtime->private_data;
/* convert to frames */
pos = bytes_to_frames(subs->runtime, pos);
count = bytes_to_frames(subs->runtime, count);
LOOP_WRITE(rec, pos, NULL, count);
return 0;
}
#endif
/*
* allocate a memory block
*/
static int emu8k_pcm_hw_params(struct snd_pcm_substream *subs,
struct snd_pcm_hw_params *hw_params)
{
struct snd_emu8k_pcm *rec = subs->runtime->private_data;
if (rec->block) {
/* reallocation - release the old block */
snd_util_mem_free(rec->emu->memhdr, rec->block);
rec->block = NULL;
}
rec->allocated_bytes = params_buffer_bytes(hw_params) + LOOP_BLANK_SIZE * 4;
rec->block = snd_util_mem_alloc(rec->emu->memhdr, rec->allocated_bytes);
if (! rec->block)
return -ENOMEM;
rec->offset = EMU8000_DRAM_OFFSET + (rec->block->offset >> 1); /* in word */
/* at least dma_bytes must be set for non-interleaved mode */
subs->dma_buffer.bytes = params_buffer_bytes(hw_params);
return 0;
}
/*
* free the memory block
*/
static int emu8k_pcm_hw_free(struct snd_pcm_substream *subs)
{
struct snd_emu8k_pcm *rec = subs->runtime->private_data;
if (rec->block) {
int ch;
for (ch = 0; ch < rec->voices; ch++)
stop_voice(rec, ch); // to be sure
if (rec->dram_opened)
emu8k_close_dram(rec->emu);
snd_util_mem_free(rec->emu->memhdr, rec->block);
rec->block = NULL;
}
return 0;
}
/*
*/
static int emu8k_pcm_prepare(struct snd_pcm_substream *subs)
{
struct snd_emu8k_pcm *rec = subs->runtime->private_data;
rec->pitch = 0xe000 + calc_rate_offset(subs->runtime->rate);
rec->last_ptr = 0;
rec->period_pos = 0;
rec->buf_size = subs->runtime->buffer_size;
rec->period_size = subs->runtime->period_size;
rec->voices = subs->runtime->channels;
rec->loop_start[0] = rec->offset + LOOP_BLANK_SIZE;
if (rec->voices > 1)
rec->loop_start[1] = rec->loop_start[0] + rec->buf_size + LOOP_BLANK_SIZE;
if (rec->voices > 1) {
rec->panning[0] = 0xff;
rec->panning[1] = 0x00;
} else
rec->panning[0] = 0x80;
if (! rec->dram_opened) {
int err, i, ch;
snd_emux_terminate_all(rec->emu->emu);
err = emu8k_open_dram_for_pcm(rec->emu, rec->voices);
if (err)
return err;
rec->dram_opened = 1;
/* clear loop blanks */
snd_emu8000_write_wait(rec->emu, 0);
EMU8000_SMALW_WRITE(rec->emu, rec->offset);
for (i = 0; i < LOOP_BLANK_SIZE; i++)
EMU8000_SMLD_WRITE(rec->emu, 0);
for (ch = 0; ch < rec->voices; ch++) {
EMU8000_SMALW_WRITE(rec->emu, rec->loop_start[ch] + rec->buf_size);
for (i = 0; i < LOOP_BLANK_SIZE; i++)
EMU8000_SMLD_WRITE(rec->emu, 0);
}
}
setup_voice(rec, 0);
if (rec->voices > 1)
setup_voice(rec, 1);
return 0;
}
static snd_pcm_uframes_t emu8k_pcm_pointer(struct snd_pcm_substream *subs)
{
struct snd_emu8k_pcm *rec = subs->runtime->private_data;
if (rec->running)
return emu8k_get_curpos(rec, 0);
return 0;
}
static const struct snd_pcm_ops emu8k_pcm_ops = {
.open = emu8k_pcm_open,
.close = emu8k_pcm_close,
.hw_params = emu8k_pcm_hw_params,
.hw_free = emu8k_pcm_hw_free,
.prepare = emu8k_pcm_prepare,
.trigger = emu8k_pcm_trigger,
.pointer = emu8k_pcm_pointer,
.copy = emu8k_pcm_copy,
.fill_silence = emu8k_pcm_silence,
};
static void snd_emu8000_pcm_free(struct snd_pcm *pcm)
{
struct snd_emu8000 *emu = pcm->private_data;
emu->pcm = NULL;
}
int snd_emu8000_pcm_new(struct snd_card *card, struct snd_emu8000 *emu, int index)
{
struct snd_pcm *pcm;
int err;
err = snd_pcm_new(card, "Emu8000 PCM", index, 1, 0, &pcm);
if (err < 0)
return err;
pcm->private_data = emu;
pcm->private_free = snd_emu8000_pcm_free;
snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &emu8k_pcm_ops);
emu->pcm = pcm;
snd_device_register(card, pcm);
return 0;
}
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