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Kernel: Allow higher audio sample rates than 65kHZ (u16)

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Executing `asctl set r 96000` no longer results in weird sample rates
being set on the audio devices. SB16 checks for a sample rate between 1
and 44100 Hz, while AC97 implements double-rate support which allows
sample rates between 8kHz and 96kHZ.
This commit is contained in:
Jelle Raaijmakers 2021-11-24 12:20:20 +01:00 • committed by Andreas Kling
parent c349634967
commit f97c9a5968
9 changed files with 56 additions and 28 deletions
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46
Kernel/Devices/Audio/AC97.cpp
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@ -13,6 +13,10 @@ namespace Kernel {
static constexpr int buffer_descriptor_list_max_entries = 32;
// Valid output range - with double-rate enabled, sample rate can go up to 96kHZ
static constexpr u16 pcm_sample_rate_minimum = 8000;
static constexpr u16 pcm_sample_rate_maximum = 48000;
static ErrorOr<OwnPtr<Memory::Region>> allocate_physical_buffer(size_t size, StringView name)
{
auto vmobject = TRY(Memory::AnonymousVMObject::try_create_physically_contiguous_with_size(Memory::page_round_up(size)));
@ -92,22 +96,31 @@ UNMAP_AFTER_INIT void AC97::initialize()
auto control = m_io_bus_base.offset(NativeAudioBusRegister::GlobalControl).in<u32>();
control |= GlobalControlFlag::GPIInterruptEnable;
control |= GlobalControlFlag::AC97ColdReset;
m_io_bus_base.offset(NativeAudioBusRegister::GlobalControl).out<u32>(control);
m_io_bus_base.offset(NativeAudioBusRegister::GlobalControl).out(control);
// Reset mixer
m_io_mixer_base.offset(NativeAudioMixerRegister::Reset).out<u16>(1);
// Verify extended capabilities
auto extended_audio_id = m_io_mixer_base.offset(NativeAudioMixerRegister::ExtendedAudioID).in<u16>();
VERIFY((extended_audio_id & ExtendedAudioMask::VariableRatePCMAudio) == 1);
VERIFY((extended_audio_id & ExtendedAudioMask::VariableRatePCMAudio) > 0);
VERIFY((extended_audio_id & ExtendedAudioMask::Revision) >> 10 == AC97Revision::Revision23);
// Enable double rate PCM audio if supported
if ((extended_audio_id & ExtendedAudioMask::DoubleRatePCMAudio) > 0) {
auto extended_audio_status_control_register = m_io_mixer_base.offset(NativeAudioMixerRegister::ExtendedAudioStatusControl);
auto extended_audio_status = extended_audio_status_control_register.in<u16>();
extended_audio_status |= ExtendedAudioStatusControlFlag::DoubleRateAudio;
extended_audio_status_control_register.out(extended_audio_status);
m_double_rate_pcm_enabled = true;
}
MUST(set_pcm_output_sample_rate(m_sample_rate));
// Left and right volume of 0 means attenuation of 0 dB
set_master_output_volume(0, 0, Muted::No);
set_pcm_output_volume(0, 0, Muted::No);
set_pcm_output_sample_rate(m_sample_rate);
reset_pcm_out();
enable_irq();
}
@ -116,15 +129,14 @@ ErrorOr<void> AC97::ioctl(OpenFileDescription&, unsigned request, Userspace<void
{
switch (request) {
case SOUNDCARD_IOCTL_GET_SAMPLE_RATE: {
auto output = static_ptr_cast<u16*>(arg);
auto output = static_ptr_cast<u32*>(arg);
return copy_to_user(output, &m_sample_rate);
}
case SOUNDCARD_IOCTL_SET_SAMPLE_RATE: {
auto sample_rate_value = static_cast<u16>(arg.ptr());
if (sample_rate_value == 0)
return EINVAL;
if (m_sample_rate != sample_rate_value)
set_pcm_output_sample_rate(sample_rate_value);
auto sample_rate = static_cast<u32>(arg.ptr());
if (sample_rate == m_sample_rate)
return {};
TRY(set_pcm_output_sample_rate(sample_rate));
return {};
}
default:
@ -151,12 +163,20 @@ void AC97::set_master_output_volume(u8 left_channel, u8 right_channel, Muted mut
m_io_mixer_base.offset(NativeAudioMixerRegister::SetMasterOutputVolume).out(volume_value);
}
void AC97::set_pcm_output_sample_rate(u16 sample_rate)
ErrorOr<void> AC97::set_pcm_output_sample_rate(u32 sample_rate)
{
auto const double_rate_shift = m_double_rate_pcm_enabled ? 1 : 0;
auto shifted_sample_rate = sample_rate >> double_rate_shift;
if (shifted_sample_rate < pcm_sample_rate_minimum || shifted_sample_rate > pcm_sample_rate_maximum)
return ENOTSUP;
auto pcm_front_dac_rate_register = m_io_mixer_base.offset(NativeAudioMixerRegister::PCMFrontDACRate);
pcm_front_dac_rate_register.out(sample_rate);
m_sample_rate = pcm_front_dac_rate_register.in<u16>();
pcm_front_dac_rate_register.out<u16>(shifted_sample_rate);
m_sample_rate = static_cast<u32>(pcm_front_dac_rate_register.in<u16>()) << double_rate_shift;
dbgln("AC97 @ {}: PCM front DAC rate set to {} Hz", pci_address(), m_sample_rate);
return {};
}
void AC97::set_pcm_output_volume(u8 left_channel, u8 right_channel, Muted mute)