jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2021-2022, Jelle Raaijmakers <jelle@gmta.nl>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#include <AK/Format.h>
8#include <Kernel/Arch/Delay.h>
9#include <Kernel/Devices/Audio/AC97.h>
10#include <Kernel/Devices/DeviceManagement.h>
11#include <Kernel/InterruptDisabler.h>
12#include <Kernel/Memory/AnonymousVMObject.h>
13
14namespace Kernel {
15
16static constexpr int buffer_descriptor_list_max_entries = 32;
17
18static constexpr u16 pcm_default_sample_rate = 44100;
19static constexpr u16 pcm_fixed_sample_rate = 48000;
20
21// Valid output range - with double-rate enabled, sample rate can go up to 96kHZ
22static constexpr u16 pcm_sample_rate_minimum = 8000;
23static constexpr u16 pcm_sample_rate_maximum = 48000;
24
25UNMAP_AFTER_INIT ErrorOr<NonnullLockRefPtr<AC97>> AC97::try_create(PCI::DeviceIdentifier const& pci_device_identifier)
26{
27 auto mixer_io_window = TRY(IOWindow::create_for_pci_device_bar(pci_device_identifier, PCI::HeaderType0BaseRegister::BAR0));
28 auto bus_io_window = TRY(IOWindow::create_for_pci_device_bar(pci_device_identifier, PCI::HeaderType0BaseRegister::BAR1));
29
30 auto pcm_out_channel_io_window = TRY(bus_io_window->create_from_io_window_with_offset(NativeAudioBusChannel::PCMOutChannel));
31 auto pcm_out_channel = TRY(AC97Channel::create_with_parent_pci_device(pci_device_identifier.address(), "PCMOut"sv, move(pcm_out_channel_io_window)));
32
33 auto ac97 = adopt_nonnull_lock_ref_or_enomem(new (nothrow) AC97(pci_device_identifier, move(pcm_out_channel), move(mixer_io_window), move(bus_io_window)));
34 if (!ac97.is_error())
35 TRY(ac97.value()->initialize());
36 return ac97;
37}
38
39UNMAP_AFTER_INIT AC97::AC97(PCI::DeviceIdentifier const& pci_device_identifier, NonnullOwnPtr<AC97Channel> pcm_out_channel, NonnullOwnPtr<IOWindow> mixer_io_window, NonnullOwnPtr<IOWindow> bus_io_window)
40 : PCI::Device(const_cast<PCI::DeviceIdentifier&>(pci_device_identifier))
41 , IRQHandler(pci_device_identifier.interrupt_line().value())
42 , m_mixer_io_window(move(mixer_io_window))
43 , m_bus_io_window(move(bus_io_window))
44 , m_pcm_out_channel(move(pcm_out_channel))
45{
46}
47
48UNMAP_AFTER_INIT AC97::~AC97() = default;
49
50bool AC97::handle_irq(RegisterState const&)
51{
52 auto pcm_out_status = m_pcm_out_channel->io_window().read16(AC97Channel::Register::Status);
53 dbgln_if(AC97_DEBUG, "AC97 @ {}: interrupt received - status: {:#05b}", device_identifier().address(), pcm_out_status);
54
55 bool is_dma_halted = (pcm_out_status & AudioStatusRegisterFlag::DMAControllerHalted) > 0;
56 bool current_equals_last_valid = (pcm_out_status & AudioStatusRegisterFlag::CurrentEqualsLastValid) > 0;
57 bool is_completion_interrupt = (pcm_out_status & AudioStatusRegisterFlag::BufferCompletionInterruptStatus) > 0;
58 bool is_fifo_error = (pcm_out_status & AudioStatusRegisterFlag::FIFOError) > 0;
59 VERIFY(!is_fifo_error);
60
61 // If there is no buffer completion, we're not going to do anything
62 if (!is_completion_interrupt)
63 return false;
64
65 // On interrupt, we need to reset PCM interrupt flags by setting their bits
66 pcm_out_status = AudioStatusRegisterFlag::LastValidBufferCompletionInterrupt
67 | AudioStatusRegisterFlag::BufferCompletionInterruptStatus
68 | AudioStatusRegisterFlag::FIFOError;
69 m_pcm_out_channel->io_window().write16(AC97Channel::Register::Status, pcm_out_status);
70
71 if (is_dma_halted) {
72 VERIFY(current_equals_last_valid);
73 m_pcm_out_channel->handle_dma_stopped();
74 }
75
76 if (!m_irq_queue.is_empty())
77 m_irq_queue.wake_all();
78
79 return true;
80}
81
82UNMAP_AFTER_INIT ErrorOr<void> AC97::initialize()
83{
84 dbgln_if(AC97_DEBUG, "AC97 @ {}: mixer base: {:#04x}", device_identifier().address(), m_mixer_io_window);
85 dbgln_if(AC97_DEBUG, "AC97 @ {}: bus base: {:#04x}", device_identifier().address(), m_bus_io_window);
86
87 // Read out AC'97 codec revision and vendor
88 auto extended_audio_id = m_mixer_io_window->read16(NativeAudioMixerRegister::ExtendedAudioID);
89 m_codec_revision = static_cast<AC97Revision>(((extended_audio_id & ExtendedAudioMask::Revision) >> 10) & 0b11);
90 dbgln_if(AC97_DEBUG, "AC97 @ {}: codec revision {:#02b}", device_identifier().address(), to_underlying(m_codec_revision));
91 if (m_codec_revision == AC97Revision::Reserved)
92 return ENOTSUP;
93
94 // Report vendor / device ID
95 u32 vendor_id = m_mixer_io_window->read16(NativeAudioMixerRegister::VendorID1) << 16 | m_mixer_io_window->read16(NativeAudioMixerRegister::VendorID2);
96 dmesgln_pci(*this, "Vendor ID: {:#8x}", vendor_id);
97
98 // Bus cold reset, enable interrupts
99 enable_pin_based_interrupts();
100 PCI::enable_bus_mastering(device_identifier());
101 auto control = m_bus_io_window->read32(NativeAudioBusRegister::GlobalControl);
102 control |= GlobalControlFlag::GPIInterruptEnable;
103 control |= GlobalControlFlag::AC97ColdReset;
104 m_bus_io_window->write32(NativeAudioBusRegister::GlobalControl, control);
105
106 // Reset mixer
107 m_mixer_io_window->write16(NativeAudioMixerRegister::Reset, 1);
108
109 // Enable variable and double rate PCM audio if supported
110 auto extended_audio_status = m_mixer_io_window->read16(NativeAudioMixerRegister::ExtendedAudioStatusControl);
111 if ((extended_audio_id & ExtendedAudioMask::VariableRatePCMAudio) > 0) {
112 extended_audio_status |= ExtendedAudioStatusControlFlag::VariableRateAudio;
113 m_variable_rate_pcm_supported = true;
114 }
115 if (!m_variable_rate_pcm_supported) {
116 extended_audio_status &= ~ExtendedAudioStatusControlFlag::DoubleRateAudio;
117 } else if ((extended_audio_id & ExtendedAudioMask::DoubleRatePCMAudio) > 0) {
118 extended_audio_status |= ExtendedAudioStatusControlFlag::DoubleRateAudio;
119 m_double_rate_pcm_enabled = true;
120 }
121 m_mixer_io_window->write16(NativeAudioMixerRegister::ExtendedAudioStatusControl, extended_audio_status);
122
123 TRY(set_pcm_output_sample_rate(m_variable_rate_pcm_supported ? pcm_default_sample_rate : pcm_fixed_sample_rate));
124
125 // Left and right volume of 0 means attenuation of 0 dB
126 set_master_output_volume(0, 0, Muted::No);
127 set_pcm_output_volume(0, 0, Muted::No);
128
129 m_pcm_out_channel->reset();
130 enable_irq();
131 return {};
132}
133
134void AC97::set_master_output_volume(u8 left_channel, u8 right_channel, Muted mute)
135{
136 u16 volume_value = ((right_channel & 63) << 0)
137 | ((left_channel & 63) << 8)
138 | ((mute == Muted::Yes ? 1 : 0) << 15);
139 m_mixer_io_window->write16(NativeAudioMixerRegister::SetMasterOutputVolume, volume_value);
140}
141
142ErrorOr<void> AC97::set_pcm_output_sample_rate(u32 sample_rate)
143{
144 if (m_sample_rate == sample_rate)
145 return {};
146
147 auto const double_rate_shift = m_double_rate_pcm_enabled ? 1 : 0;
148 auto shifted_sample_rate = sample_rate >> double_rate_shift;
149 if (!m_variable_rate_pcm_supported && shifted_sample_rate != pcm_fixed_sample_rate)
150 return ENOTSUP;
151 if (shifted_sample_rate < pcm_sample_rate_minimum || shifted_sample_rate > pcm_sample_rate_maximum)
152 return ENOTSUP;
153
154 m_mixer_io_window->write16(NativeAudioMixerRegister::PCMFrontDACRate, shifted_sample_rate);
155 m_sample_rate = static_cast<u32>(m_mixer_io_window->read16(NativeAudioMixerRegister::PCMFrontDACRate)) << double_rate_shift;
156
157 dmesgln_pci(*this, "PCM front DAC rate set to {} Hz", m_sample_rate);
158
159 // Setting the sample rate stops a running DMA engine, so restart it
160 if (m_pcm_out_channel->dma_running())
161 m_pcm_out_channel->start_dma();
162
163 return {};
164}
165
166void AC97::set_pcm_output_volume(u8 left_channel, u8 right_channel, Muted mute)
167{
168 u16 volume_value = ((right_channel & 31) << 0)
169 | ((left_channel & 31) << 8)
170 | ((mute == Muted::Yes ? 1 : 0) << 15);
171 m_mixer_io_window->write16(NativeAudioMixerRegister::SetPCMOutputVolume, volume_value);
172}
173
174LockRefPtr<AudioChannel> AC97::audio_channel(u32 index) const
175{
176 if (index == 0)
177 return m_audio_channel;
178 return {};
179}
180
181void AC97::detect_hardware_audio_channels(Badge<AudioManagement>)
182{
183 m_audio_channel = AudioChannel::must_create(*this, 0);
184}
185
186ErrorOr<void> AC97::set_pcm_output_sample_rate(size_t channel_index, u32 samples_per_second_rate)
187{
188 if (channel_index != 0)
189 return ENODEV;
190 TRY(set_pcm_output_sample_rate(samples_per_second_rate));
191 return {};
192}
193
194ErrorOr<u32> AC97::get_pcm_output_sample_rate(size_t channel_index)
195{
196 if (channel_index != 0)
197 return Error::from_errno(ENODEV);
198 return m_sample_rate;
199}
200
201ErrorOr<size_t> AC97::write(size_t channel_index, UserOrKernelBuffer const& data, size_t length)
202{
203 if (channel_index != 0)
204 return Error::from_errno(ENODEV);
205
206 if (!m_output_buffer)
207 m_output_buffer = TRY(MM.allocate_dma_buffer_pages(m_output_buffer_page_count * PAGE_SIZE, "AC97 Output buffer"sv, Memory::Region::Access::Write));
208
209 if (!m_buffer_descriptor_list) {
210 size_t buffer_descriptor_list_size = buffer_descriptor_list_max_entries * sizeof(BufferDescriptorListEntry);
211 buffer_descriptor_list_size = TRY(Memory::page_round_up(buffer_descriptor_list_size));
212 m_buffer_descriptor_list = TRY(MM.allocate_dma_buffer_pages(buffer_descriptor_list_size, "AC97 Buffer Descriptor List"sv, Memory::Region::Access::Write));
213 }
214
215 Checked<size_t> remaining = length;
216 size_t offset = 0;
217 while (remaining > static_cast<size_t>(0)) {
218 TRY(write_single_buffer(data, offset, min(remaining.value(), PAGE_SIZE)));
219 offset += PAGE_SIZE;
220 remaining.saturating_sub(PAGE_SIZE);
221 }
222
223 return length;
224}
225
226ErrorOr<void> AC97::write_single_buffer(UserOrKernelBuffer const& data, size_t offset, size_t length)
227{
228 VERIFY(length <= PAGE_SIZE);
229
230 {
231 // Block until we can write into an unused buffer
232 InterruptDisabler disabler;
233 do {
234 auto pcm_out_status = m_pcm_out_channel->io_window().read16(AC97Channel::Register::Status);
235 auto current_index = m_pcm_out_channel->io_window().read8(AC97Channel::Register::CurrentIndexValue);
236 int last_valid_index = m_pcm_out_channel->io_window().read8(AC97Channel::Register::LastValidIndex);
237
238 auto head_distance = last_valid_index - current_index;
239 if (head_distance < 0)
240 head_distance += buffer_descriptor_list_max_entries;
241 if (m_pcm_out_channel->dma_running())
242 ++head_distance;
243
244 // Current index has _passed_ last valid index - move our list index up
245 if (head_distance > m_output_buffer_page_count) {
246 m_buffer_descriptor_list_index = current_index + 1;
247 break;
248 }
249
250 // There is room for our data
251 if (head_distance < m_output_buffer_page_count)
252 break;
253
254 dbgln_if(AC97_DEBUG, "AC97 @ {}: waiting on interrupt - status: {:#05b} CI: {} LVI: {}", device_identifier().address(), pcm_out_status, current_index, last_valid_index);
255 m_irq_queue.wait_forever("AC97"sv);
256 } while (m_pcm_out_channel->dma_running());
257 }
258 // Copy data from userspace into one of our buffers
259 TRY(data.read(m_output_buffer->vaddr_from_page_index(m_output_buffer_page_index).as_ptr(), offset, length));
260
261 // Write the next entry to the buffer descriptor list
262 u16 number_of_samples = length / sizeof(u16);
263 auto list_entries = reinterpret_cast<BufferDescriptorListEntry*>(m_buffer_descriptor_list->vaddr().get());
264 auto list_entry = &list_entries[m_buffer_descriptor_list_index];
265 list_entry->buffer_pointer = static_cast<u32>(m_output_buffer->physical_page(m_output_buffer_page_index)->paddr().get());
266 list_entry->control_and_length = number_of_samples | BufferDescriptorListEntryFlags::InterruptOnCompletion;
267
268 auto buffer_address = static_cast<u32>(m_buffer_descriptor_list->physical_page(0)->paddr().get());
269 m_pcm_out_channel->set_last_valid_index(buffer_address, m_buffer_descriptor_list_index);
270
271 if (!m_pcm_out_channel->dma_running())
272 m_pcm_out_channel->start_dma();
273
274 m_output_buffer_page_index = (m_output_buffer_page_index + 1) % m_output_buffer_page_count;
275 m_buffer_descriptor_list_index = (m_buffer_descriptor_list_index + 1) % buffer_descriptor_list_max_entries;
276
277 return {};
278}
279
280ErrorOr<NonnullOwnPtr<AC97::AC97Channel>> AC97::AC97Channel::create_with_parent_pci_device(PCI::Address pci_device_address, StringView name, NonnullOwnPtr<IOWindow> channel_io_base)
281{
282 return adopt_nonnull_own_or_enomem(new (nothrow) AC97::AC97Channel(pci_device_address, name, move(channel_io_base)));
283}
284
285void AC97::AC97Channel::handle_dma_stopped()
286{
287 dbgln_if(AC97_DEBUG, "AC97 @ {}: channel {}: DMA engine has stopped", m_device_pci_address, name());
288 m_dma_running.with([this](auto& dma_running) {
289 // NOTE: QEMU might send spurious interrupts while we're not running, so we don't want to panic here.
290 if (!dma_running)
291 dbgln("AC97 @ {}: received DMA interrupt while it wasn't running", m_device_pci_address);
292 dma_running = false;
293 });
294}
295
296void AC97::AC97Channel::reset()
297{
298 dbgln_if(AC97_DEBUG, "AC97 @ {}: channel {}: resetting", m_device_pci_address, name());
299
300 m_channel_io_window->write8(Register::Control, AudioControlRegisterFlag::ResetRegisters);
301
302 while ((m_channel_io_window->read8(Register::Control) & AudioControlRegisterFlag::ResetRegisters) > 0)
303 microseconds_delay(50);
304
305 m_dma_running.with([](auto& dma_running) {
306 dma_running = false;
307 });
308}
309
310void AC97::AC97Channel::set_last_valid_index(u32 buffer_address, u8 last_valid_index)
311{
312 dbgln_if(AC97_DEBUG, "AC97 @ {}: channel {}: setting buffer address: {:#x} LVI: {}", m_device_pci_address, name(), buffer_address, last_valid_index);
313
314 m_channel_io_window->write32(Register::BufferDescriptorListBaseAddress, buffer_address);
315 m_channel_io_window->write8(Register::LastValidIndex, last_valid_index);
316}
317
318void AC97::AC97Channel::start_dma()
319{
320 dbgln_if(AC97_DEBUG, "AC97 @ {}: channel {}: starting DMA engine", m_device_pci_address, name());
321
322 auto control = m_channel_io_window->read8(Register::Control);
323 control |= AudioControlRegisterFlag::RunPauseBusMaster;
324 control |= AudioControlRegisterFlag::FIFOErrorInterruptEnable;
325 control |= AudioControlRegisterFlag::InterruptOnCompletionEnable;
326 m_channel_io_window->write8(Register::Control, control);
327
328 m_dma_running.with([](auto& dma_running) {
329 dma_running = true;
330 });
331}
332
333}