toaruos/modules/ac97.c

394 lines
12 KiB
C

/**
* @file kernel/audio/ac97.c
* @brief Driver for the Intel AC'97.
* @package x86_64
* @package aarch64
*
* Simple PCM interface for the AC'97 codec when used with the
* ICH hardware interface. There are other hardware interfaces
* that use this codec and this driver could probably be ported
* to them.
*
* Note that the audio subsystem is intended to be non-blocking
* so that buffer filling can be done directly in interrupt handlers.
*
* @see http://www.intel.com/design/chipsets/manuals/29802801.pdf
*
* @copyright
* This file is part of ToaruOS and is released under the terms
* of the NCSA / University of Illinois License - see LICENSE.md
* Copyright (C) 2015 Michael Gerow
* Copyright (C) 2015-2021 K. Lange
*/
#include <errno.h>
#include <kernel/types.h>
#include <kernel/string.h>
#include <kernel/printf.h>
#include <kernel/pci.h>
#include <kernel/process.h>
#include <kernel/mmu.h>
#include <kernel/list.h>
#include <kernel/module.h>
#include <kernel/mod/snd.h>
#if defined(__x86_64__)
#include <kernel/arch/x86_64/ports.h>
#include <kernel/arch/x86_64/regs.h>
#include <kernel/arch/x86_64/irq.h>
#elif defined(__aarch64__)
#include <kernel/arch/aarch64/gic.h>
#endif
/* Utility macros */
#define N_ELEMENTS(arr) (sizeof(arr) / sizeof((arr)[0]))
/* BARs! */
#define AC97_NAMBAR 0x10 /* Native Audio Mixer Base Address Register */
#define AC97_NABMBAR 0x14 /* Native Audio Bus Mastering Base Address Register */
/* Bus mastering IO port offsets */
#define AC97_PO_BDBAR 0x10 /* PCM out buffer descriptor BAR */
#define AC97_PO_CIV 0x14 /* PCM out current index value */
#define AC97_PO_LVI 0x15 /* PCM out last valid index */
#define AC97_PO_SR 0x16 /* PCM out status register */
#define AC97_PO_PICB 0x18 /* PCM out position in current buffer register */
#define AC97_PO_CR 0x1B /* PCM out control register */
/* Bus mastering misc */
/* Buffer descriptor list constants */
#define AC97_BDL_LEN 32 /* Buffer descriptor list length */
#define AC97_BDL_BUFFER_LEN 0x1000 /* Length of buffer in BDL */
#define AC97_CL_GET_LENGTH(cl) ((cl) & 0xFFFF) /* Decode length from cl */
#define AC97_CL_SET_LENGTH(cl, v) ((cl) = (v) & 0xFFFF) /* Encode length to cl */
#define AC97_CL_BUP ((uint32_t)1 << 30) /* Buffer underrun policy in cl */
#define AC97_CL_IOC ((uint32_t)1 << 31) /* Interrupt on completion flag in cl */
/* PCM out control register flags */
#define AC97_X_CR_RPBM (1 << 0) /* Run/pause bus master */
#define AC97_X_CR_RR (1 << 1) /* Reset registers */
#define AC97_X_CR_LVBIE (1 << 2) /* Last valid buffer interrupt enable */
#define AC97_X_CR_FEIE (1 << 3) /* FIFO error interrupt enable */
#define AC97_X_CR_IOCE (1 << 4) /* Interrupt on completion enable */
/* Status register flags */
#define AC97_X_SR_DCH (1 << 0) /* DMA controller halted */
#define AC97_X_SR_CELV (1 << 1) /* Current equals last valid */
#define AC97_X_SR_LVBCI (1 << 2) /* Last valid buffer completion interrupt */
#define AC97_X_SR_BCIS (1 << 3) /* Buffer completion interrupt status */
#define AC97_X_SR_FIFOE (1 << 4) /* FIFO error */
/* Mixer IO port offsets */
#define AC97_RESET 0x00
#define AC97_MASTER_VOLUME 0x02
#define AC97_AUX_OUT_VOLUME 0x04
#define AC97_MONO_VOLUME 0x06
#define AC97_PCM_OUT_VOLUME 0x18
/* snd values */
#define AC97_SND_NAME "Intel AC'97"
#define AC97_PLAYBACK_SPEED 48000
#define AC97_PLAYBACK_FORMAT SND_FORMAT_L16SLE
/* An entry in a buffer dscriptor list */
typedef struct {
uint32_t pointer; /* Pointer to buffer */
uint32_t cl; /* Control values and buffer length */
} __attribute__((packed)) ac97_bdl_entry_t;
typedef struct {
uint32_t pci_device;
uint16_t nabmbar; /* Native audio bus mastring BAR */
uint16_t nambar; /* Native audio mixing BAR */
size_t irq; /* This ac97's irq */
uint8_t lvi; /* The currently set last valid index */
uint8_t bits; /* How many bits of volume are supported (5 or 6) */
ac97_bdl_entry_t * bdl; /* Buffer descriptor list */
uint16_t * bufs[AC97_BDL_LEN]; /* Virtual addresses for buffers in BDL */
uint32_t bdl_p;
uint32_t mask;
volatile char * _iobase;
spin_lock_t lock;
} ac97_device_t;
static ac97_device_t _device;
#if defined(__aarch64__)
static uint8_t inportb(size_t port) {
volatile uint8_t * _port = (volatile uint8_t*)(_device._iobase + port);
return *_port;
}
static uint16_t inports(size_t port) {
volatile uint16_t * _port = (volatile uint16_t*)(_device._iobase + port);
return *_port;
}
static uint32_t inportl(size_t port) {
volatile uint32_t * _port = (volatile uint32_t*)(_device._iobase + port);
return *_port;
}
static void outportb(size_t port, uint8_t val) {
volatile uint8_t * _port = (volatile uint8_t*)(_device._iobase + port);
*_port = val;
}
static void outports(size_t port, uint16_t val) {
volatile uint16_t * _port = (volatile uint16_t*)(_device._iobase + port);
*_port = val;
}
static void outportl(size_t port, uint32_t val) {
volatile uint32_t * _port = (volatile uint32_t*)(_device._iobase + port);
*_port = val;
}
#endif
#define AC97_KNOB_PCM_OUT (SND_KNOB_VENDOR + 0)
static snd_knob_t _knobs[] = {
{
"Master",
SND_KNOB_MASTER
},
{
"PCM Out",
SND_KNOB_VENDOR + 0
}
};
static int ac97_mixer_read(uint32_t knob_id, uint32_t *val);
static int ac97_mixer_write(uint32_t knob_id, uint32_t val);
static snd_device_t _snd = {
.name = AC97_SND_NAME,
.device = &_device,
.playback_speed = AC97_PLAYBACK_SPEED,
.playback_format = AC97_PLAYBACK_FORMAT,
.knobs = _knobs,
.num_knobs = N_ELEMENTS(_knobs),
.mixer_read = ac97_mixer_read,
.mixer_write = ac97_mixer_write,
};
/*
* This could be unnecessary if we instead allocate just two buffers and make
* the ac97 think there are more.
*/
static void find_ac97(uint32_t device, uint16_t vendorid, uint16_t deviceid, void * extra) {
ac97_device_t * ac97 = extra;
if ((vendorid == 0x8086) && (deviceid == 0x2415)) {
ac97->pci_device = device;
}
}
#define DIVISION 0x1000
#if defined(__x86_64__)
static int ac97_irq_handler(struct regs * regs) {
#elif defined(__aarch64__)
int ac97_irq_handler(process_t * this, int irq, void * data) {
#endif
spin_lock(_device.lock);
uint16_t sr = inports(_device.nabmbar + AC97_PO_SR);
if (sr & AC97_X_SR_BCIS) {
outports(_device.nabmbar + AC97_PO_SR, AC97_X_SR_BCIS);
spin_unlock(_device.lock);
uint16_t current_buffer = inportb(_device.nabmbar + AC97_PO_CIV);
uint16_t last_valid = ((current_buffer+2) & (AC97_BDL_LEN-1));
snd_request_buf(&_snd, 0x1000, (uint8_t *)_device.bufs[last_valid]);
outportb(_device.nabmbar + AC97_PO_LVI, last_valid);
snd_request_buf(&_snd, 0x1000, (uint8_t *)_device.bufs[last_valid]+0x1000);
} else if (sr & AC97_X_SR_LVBCI) {
outports(_device.nabmbar + AC97_PO_SR, AC97_X_SR_LVBCI);
spin_unlock(_device.lock);
} else if (sr & AC97_X_SR_FIFOE) {
outports(_device.nabmbar + AC97_PO_SR, AC97_X_SR_FIFOE);
spin_unlock(_device.lock);
} else {
spin_unlock(_device.lock);
return 0;
}
#ifdef __x86_64__
irq_ack(_device.irq);
#endif
return 1;
}
/* Currently we just assume right and left are the same */
static int ac97_mixer_read(uint32_t knob_id, uint32_t *val) {
uint16_t tmp;
switch (knob_id) {
case SND_KNOB_MASTER:
tmp = inports(_device.nambar + AC97_MASTER_VOLUME);
if (tmp == 0x8000) {
*val = 0;
} else {
/* 6 bit value */
*val = (tmp & _device.mask) << (sizeof(*val) * 8 - _device.bits);
*val = ~*val;
*val &= (uint32_t)_device.mask << (sizeof(*val) * 8 - _device.bits);
}
break;
case AC97_KNOB_PCM_OUT:
tmp = inports(_device.nambar + AC97_PCM_OUT_VOLUME);
if (tmp == 0x8000) {
*val = 0;
} else {
/* 5 bit value */
*val = (tmp & 0x1f) << (sizeof(*val) * 8 - 5);
*val = ~*val;
*val &= 0x1f << (sizeof(*val) * 8 - 5);
}
break;
default:
return -1;
}
return 0;
}
static int ac97_mixer_write(uint32_t knob_id, uint32_t val) {
switch (knob_id) {
case SND_KNOB_MASTER: {
uint16_t encoded;
if (val == 0x0) {
encoded = 0x8000;
} else {
/* 0 is the highest volume */
val = ~val;
/* 6 bit value */
val >>= (sizeof(val) * 8 - _device.bits);
encoded = (val & 0xFF) | (val << 8);
}
outports(_device.nambar + AC97_MASTER_VOLUME, encoded);
break;
}
case AC97_KNOB_PCM_OUT: {
uint16_t encoded;
if (val == 0x0) {
encoded = 0x8000;
} else {
/* 0 is the highest volume */
val = ~val;
/* 5 bit value */
val >>= (sizeof(val) * 8 - 5);
encoded = (val & 0xFF) | (val << 8);
}
outports(_device.nambar + AC97_PCM_OUT_VOLUME, encoded);
break;
}
default:
return -1;
}
return 0;
}
static int ac97_install(int argc, char * argv[]) {
//debug_print(NOTICE, "Initializing AC97");
pci_scan(&find_ac97, -1, &_device);
if (!_device.pci_device) {
return -ENODEV;
}
#if defined(__aarch64__)
pci_write_field(_device.pci_device, PCI_COMMAND, 2, 0x5);
pci_write_field(_device.pci_device, AC97_NABMBAR, 2, 0x1001);
pci_write_field(_device.pci_device, PCI_BAR0, 4, 0x2001);
_device._iobase = (volatile char *)mmu_map_mmio_region(0x3eff0000, 0x3000);
asm volatile ("isb" ::: "memory");
#endif
_device.nabmbar = pci_read_field(_device.pci_device, AC97_NABMBAR, 2) & ((uint32_t) -1) << 1;
_device.nambar = pci_read_field(_device.pci_device, PCI_BAR0, 4) & ((uint32_t) -1) << 1;
#if defined(__x86_64__)
_device.irq = pci_get_interrupt(_device.pci_device);
//printf("device wants irq %zd\n", _device.irq);
irq_install_handler(_device.irq, ac97_irq_handler, "ac97");
#elif defined(__aarch64__)
int irq;
gic_map_pci_interrupt("ac97",_device.pci_device,&irq,ac97_irq_handler,&_device);
_device.irq = irq;
#endif
/* Enable all matter of interrupts */
outportb(_device.nabmbar + AC97_PO_CR, AC97_X_CR_FEIE | AC97_X_CR_IOCE);
/* Enable bus mastering and disable memory mapped space */
pci_write_field(_device.pci_device, PCI_COMMAND, 2, 0x5);
/* Default the PCM output to full volume. */
outports(_device.nambar + AC97_PCM_OUT_VOLUME, 0x0000);
/* Allocate our BDL and our buffers */
_device.bdl_p = mmu_allocate_a_frame() << 12;
_device.bdl = mmu_map_from_physical(_device.bdl_p);
memset(_device.bdl, 0, AC97_BDL_LEN * sizeof(*_device.bdl));
for (int i = 0; i < AC97_BDL_LEN; i++) {
_device.bdl[i].pointer = mmu_allocate_n_frames(2) << 12;
_device.bufs[i] = mmu_map_from_physical(_device.bdl[i].pointer);
memset(_device.bufs[i], 0, AC97_BDL_BUFFER_LEN * sizeof(*_device.bufs[0]));
AC97_CL_SET_LENGTH(_device.bdl[i].cl, AC97_BDL_BUFFER_LEN);
/* Set all buffers to interrupt */
_device.bdl[i].cl |= AC97_CL_IOC;
}
/* Tell the ac97 where our BDL is */
outportl(_device.nabmbar + AC97_PO_BDBAR, _device.bdl_p);
/* Set the LVI to be the last index */
_device.lvi = 2;
outportb(_device.nabmbar + AC97_PO_LVI, _device.lvi);
/* detect whether device supports MSB */
outports(_device.nambar + AC97_MASTER_VOLUME, 0x2020);
uint16_t t = inports(_device.nambar + AC97_MASTER_VOLUME) & 0x1f;
if (t == 0x1f) {
//debug_print(WARNING, "This device only supports 5 bits of audio volume.");
_device.bits = 5;
_device.mask = 0x1f;
} else {
_device.bits = 6;
_device.mask = 0x3f;
}
outports(_device.nambar + AC97_MASTER_VOLUME, 0x0000);
snd_register(&_snd);
/* Start things playing */
outportb(_device.nabmbar + AC97_PO_CR, inportb(_device.nabmbar + AC97_PO_CR) | AC97_X_CR_RPBM);
//debug_print(NOTICE, "AC97 initialized successfully");
return 0;
}
static int fini(void) {
snd_unregister(&_snd);
free(_device.bdl);
for (int i = 0; i < AC97_BDL_LEN; i++) {
free(_device.bufs[i]);
}
return 0;
}
struct Module metadata = {
.name = "ac97",
.init = ac97_install,
.fini = fini,
};