diff options
Diffstat (limited to 'kernel/drivers/ac97.c')
| -rw-r--r-- | kernel/drivers/ac97.c | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/kernel/drivers/ac97.c b/kernel/drivers/ac97.c new file mode 100644 index 0000000..24899dd --- /dev/null +++ b/kernel/drivers/ac97.c @@ -0,0 +1,233 @@ +#include <assert.h> +#include <cpu/io.h> +#include <drivers/ac97.h> +#include <drivers/pci.h> +#include <fcntl.h> +#include <fs/vfs.h> +#include <kmalloc.h> +#include <random.h> + +struct PCI_DEVICE ac97; +struct PCI_BaseAddressRegister nabm; +struct PCI_BaseAddressRegister nam; + +int current_pointer = 0; + +void *physical_buffer_descriptor_list; +u16 *buffer_descriptor_list; +u16 *pointer; + +struct audio_buffer { + volatile u8 *data; + uintptr_t physical; + int has_played; +}; + +struct audio_buffer buffers[32]; + +void add_buffer(void) { + u16 *pointer = buffer_descriptor_list; + for (int i = 0; i < 4; i++) { + void *physical_audio_data; + u8 *audio_data = kmalloc_align(128000, &physical_audio_data); + + buffers[i].data = audio_data; + buffers[i].physical = physical_audio_data; + buffers[i].has_played = 1; + + *((u32 *)pointer) = physical_audio_data; + pointer += 2; + *pointer = 128000 / 2; + pointer++; + *pointer = (1 << 14); + pointer++; + } +} + +void add_to_list(u8 *buffer, size_t size) { + void *physical_audio_data; + u8 *audio_data = kmalloc_align(size, &physical_audio_data); + memcpy(audio_data, buffer, size); + + // Write number of last valid buffer entry to Last Valid Entry + // register (NABM register 0x15) + outb(nabm.address + 0x10 + 0x5, 1); + + // Set bit for transfering data (NABM register 0x1B, value 0x1) + u8 s = inb(nabm.address + 0x10 + 0xB); + s |= (1 << 0); + outb(nabm.address + 0x10 + 0xB, s); + + outl(nabm.address + 0x10 + 0x0, physical_buffer_descriptor_list); +} + +int entry = 0; + +void start(void) { + // // Write number of last valid buffer entry to Last Valid Entry + // // register (NABM register 0x15) + // outb(nabm.address + 0x10 + 0x5, 1); + + // Set bit for transfering data (NABM register 0x1B, value 0x1) + u8 s = inb(nabm.address + 0x10 + 0xB); + if (s & (1 << 0)) { + return; + } + s |= (1 << 0); + outb(nabm.address + 0x10 + 0xB, s); +} + +void play_pcm(u8 *buffer, size_t size) { + if (entry >= 3) { + outb(nabm.address + 0x10 + 0x5, entry - 1); + return; + } + if (!buffers[entry].has_played) { + for (;;) { + u8 process_num = inb(nabm.address + 0x10 + 0x4); + kprintf("process_num: %d\n", process_num); + if (process_num > entry) { + buffers[entry].has_played = 1; + break; + } + } + } + memcpy((u8 *)buffers[entry].data, buffer, size); + outb(nabm.address + 0x10 + 0x5, entry); + buffers[entry].has_played = 0; + + entry++; + + /* + u8 process_num = inb(nabm.address + 0x10 + 0x4); + kprintf("process_num: %d\n", process_num); + + if (0 == process_num) + return; + */ +} + +void ac97_init(void) { + if (!pci_populate_device_struct(0x8086, 0x2415, &ac97)) { + assert(0); + return; + } + pointer = buffer_descriptor_list = + kmalloc_align(0x1000, &physical_buffer_descriptor_list); + + // Enable bus mastering + u32 register1 = pci_config_read32(&ac97, 0, 0x4); + register1 |= (1 << 0); + register1 |= (1 << 2); + pci_config_write32(&ac97, 0, 0x4, register1); + + assert(pci_get_bar(&ac97, 1, &nabm)); + assert(nabm.type == PCI_BAR_IO); + + assert(pci_get_bar(&ac97, 0, &nam)); + assert(nam.type == PCI_BAR_IO); + + /* + In initalization of sound card you must resume card from cold reset + and set power for it. It can be done by writing value 0x2 to Global + Control register if you do not want to use interrupts, or 0x3 if you + want to use interrupts. + */ + + outl(nabm.address + 0x2C, (1 << 1)); + + /* + After this, you should write any value to NAM + Reset register to reset all NAM registers. + */ + + outw(nam.address + 0x0, 0x1); + + /* + After this, you can read + card capability info from Global Status register to found out if 20 + bit audio samples are supported and also check out bit 4 in NAM + Capabilites register and value in AUX Output to find out if this sound + card support headhone output. + */ + + // 0x30 Global Status Register dword + u32 status = inl(nabm.address + 0x30); + + u8 channel_capabilities = (status >> 20) & 0x3; + u8 sample_capabilities = (status >> 22) & 0x3; + kprintf("channel: %d\n", channel_capabilities); + kprintf("sample: %d\n", sample_capabilities); + + // outw(nam.address + 0x2C, 16000 / 2); + outw(nam.address + 0x2C, 48000 / 2); + u16 sample_rate = inw(nam.address + 0x2C); + kprintf("sample_rate: %d\n", sample_rate); + sample_rate = inw(nam.address + 0x2E); + kprintf("sample_rate: %d\n", sample_rate); + sample_rate = inw(nam.address + 0x30); + kprintf("sample_rate: %d\n", sample_rate); + sample_rate = inw(nam.address + 0x32); + kprintf("sample_rate: %d\n", sample_rate); + + /* + As last thing, set maximal volume for + PCM Output by writing value 0 to this register. Now sound card is + ready to use. + */ + + // Set PCM Output Volume + outw(nam.address + 0x18, 0); + + // Playing sound + /* + Set volume of output you want to use - Master Volume register (NAM + register 0x02) for speaker and if supported, AUX Output register (NAM + register 0x04) for headphone + */ + // FIXME: Speaker but is this correct? + outw(nam.address + 0x02, 0); + outw(nam.address + 0x04, 0); + + // SETUP? + + // Set reset bit of output channel (NABM register 0x1B, value 0x2) and + // wait for card to clear it + u8 s = inb(nabm.address + 0x10 + 0xB); + s |= (1 << 1); + outb(nabm.address + 0x10 + 0xB, s); + + kprintf("wait for clear\n"); + for (; inb(nabm.address + 0x10 + 0xB) & (1 << 1);) + ; + kprintf("cleared\n"); + + add_buffer(); + + // Write physical position of BDL to Buffer Descriptor Base Address + // register (NABM register 0x10) + outl(nabm.address + 0x10 + 0x0, physical_buffer_descriptor_list); + + // END SETUP? + + int fd = vfs_open("/hq.pcm", O_RDONLY, 0); + assert(0 >= fd); + size_t offset = 0; + size_t capacity = 128000; + char *data = kmalloc(capacity); + for (;;) { + int rc = vfs_pread(fd, data, capacity, offset); + if (0 == rc) { + break; + } + if (rc < 0) { + kprintf("rc: %d\n", rc); + assert(0); + } + play_pcm(data, rc); + start(); + offset += rc; + } + for (;;) + ; +} |