service/cam: Implement Vsync interrupt callbacks

According to HW tests, this vsync event is signaled for activated cameras at about the same frequency as the frame rate. The last 5 vsync timings are recorded (in microseconds) and can be retrieved with the service function.

Also, corrected the default frame_rate to 15, according to HW test.

This should fix the missing camera images in certain games.

src/core/hle/service/cam/cam.cpp

@@ -60,6 +60,7 @@ void Module::PortConfig::Clear() {
     completion_event->Clear();
     buffer_error_interrupt_event->Clear();
     vsync_interrupt_event->Clear();
+    vsync_timings.clear();
     is_receiving = false;
     is_active = false;
     is_pending_receiving = false;
@@ -133,6 +134,27 @@ void Module::CompletionEventCallBack(u64 port_id, s64) {
     port.completion_event->Signal();
 }
 
+static constexpr std::size_t MaxVsyncTimings = 5;
+
+void Module::VsyncInterruptEventCallBack(u64 port_id, s64 cycles_late) {
+    PortConfig& port = ports[port_id];
+    const CameraConfig& camera = cameras[port.camera_id];
+
+    if (!port.is_active) {
+        return;
+    }
+
+    port.vsync_timings.emplace_front(system.CoreTiming().GetGlobalTimeUs().count());
+    if (port.vsync_timings.size() > MaxVsyncTimings) {
+        port.vsync_timings.pop_back();
+    }
+    port.vsync_interrupt_event->Signal();
+
+    system.CoreTiming().ScheduleEvent(
+        msToCycles(LATENCY_BY_FRAME_RATE[static_cast<int>(camera.frame_rate)]) - cycles_late,
+        vsync_interrupt_event_callback, port_id);
+}
+
 void Module::StartReceiving(int port_id) {
     PortConfig& port = ports[port_id];
     port.is_receiving = true;
@@ -173,6 +195,9 @@ void Module::ActivatePort(int port_id, int camera_id) {
     }
     ports[port_id].is_active = true;
     ports[port_id].camera_id = camera_id;
+    system.CoreTiming().ScheduleEvent(
+        msToCycles(LATENCY_BY_FRAME_RATE[static_cast<int>(cameras[camera_id].frame_rate)]),
+        vsync_interrupt_event_callback, port_id);
 }
 
 template <int max_index>
@@ -631,6 +656,7 @@ void Module::Interface::Activate(Kernel::HLERequestContext& ctx) {
                     cam->ports[i].is_busy = false;
                 }
                 cam->ports[i].is_active = false;
+                cam->system.CoreTiming().UnscheduleEvent(cam->vsync_interrupt_event_callback, i);
             }
             rb.Push(RESULT_SUCCESS);
         } else if (camera_select[0] && camera_select[1]) {
@@ -860,6 +886,33 @@ void Module::Interface::SynchronizeVsyncTiming(Kernel::HLERequestContext& ctx) {
                 camera_select1, camera_select2);
 }
 
+void Module::Interface::GetLatestVsyncTiming(Kernel::HLERequestContext& ctx) {
+    IPC::RequestParser rp(ctx, 0x2A, 2, 0);
+    const PortSet port_select(rp.Pop<u8>());
+    const u32 count = rp.Pop<u32>();
+
+    if (!port_select.IsSingle() || count > MaxVsyncTimings) {
+        IPC::RequestBuilder rb = rp.MakeBuilder(1, 2);
+        rb.Push(ERROR_OUT_OF_RANGE);
+        rb.PushStaticBuffer({}, 0);
+        return;
+    }
+
+    IPC::RequestBuilder rb = rp.MakeBuilder(1, 2);
+    rb.Push(RESULT_SUCCESS);
+
+    std::vector<u8> out(count * sizeof(s64_le));
+    std::size_t offset = 0;
+    for (const s64_le timing : cam->ports[port_select.m_val].vsync_timings) {
+        std::memcpy(out.data() + offset * sizeof(timing), &timing, sizeof(timing));
+        offset++;
+        if (offset >= count) {
+            break;
+        }
+    }
+    rb.PushStaticBuffer(out, 0);
+}
+
 void Module::Interface::GetStereoCameraCalibrationData(Kernel::HLERequestContext& ctx) {
     IPC::RequestBuilder rb = IPC::RequestParser(ctx, 0x2B, 0, 0).MakeBuilder(17, 0);
 
@@ -1032,6 +1085,10 @@ Module::Module(Core::System& system) : system(system) {
     completion_event_callback = system.CoreTiming().RegisterEvent(
         "CAM::CompletionEventCallBack",
         [this](u64 userdata, s64 cycles_late) { CompletionEventCallBack(userdata, cycles_late); });
+    vsync_interrupt_event_callback = system.CoreTiming().RegisterEvent(
+        "CAM::VsyncInterruptEventCallBack", [this](u64 userdata, s64 cycles_late) {
+            VsyncInterruptEventCallBack(userdata, cycles_late);
+        });
 }
 
 Module::~Module() {

src/core/hle/service/cam/cam.h

@@ -5,6 +5,7 @@
 #pragma once
 
 #include <array>
+#include <deque>
 #include <future>
 #include <memory>
 #include <vector>
@@ -616,6 +617,21 @@ public:
          */
         void SynchronizeVsyncTiming(Kernel::HLERequestContext& ctx);
 
+        /**
+         * Gets the vsync timing record of the specified camera for the specified number of signals.
+         *  Inputs:
+         *      0: 0x002A0080
+         *      1: Port
+         *      2: Number of timings to get
+         *      64: ((PastTimings * 8) << 14) | 2
+         *      65: s64* TimingsOutput
+         *  Outputs:
+         *      0: 0x002A0042
+         *      1: ResultCode
+         *      2-3: Output static buffer
+         */
+        void GetLatestVsyncTiming(Kernel::HLERequestContext& ctx);
+
         /**
          * Returns calibration data relating the outside cameras to each other, for use in AR
          * applications.
@@ -716,6 +732,7 @@ public:
 
 private:
     void CompletionEventCallBack(u64 port_id, s64);
+    void VsyncInterruptEventCallBack(u64 port_id, s64 cycles_late);
 
     // Starts a receiving process on the specified port. This can only be called when is_busy = true
     // and is_receiving = false.
@@ -744,7 +761,7 @@ private:
         std::unique_ptr<Camera::CameraInterface> impl;
         std::array<ContextConfig, 2> contexts;
         int current_context{0};
-        FrameRate frame_rate{FrameRate::Rate_5};
+        FrameRate frame_rate{FrameRate::Rate_15};
     };
 
     struct PortConfig {
@@ -773,6 +790,8 @@ private:
         std::shared_ptr<Kernel::Event> buffer_error_interrupt_event;
         std::shared_ptr<Kernel::Event> vsync_interrupt_event;
 
+        std::deque<s64> vsync_timings;
+
         std::future<std::vector<u16>> capture_result; // will hold the received frame.
         Kernel::Process* dest_process{nullptr};
         VAddr dest{0};    // the destination address of the receiving process
@@ -787,6 +806,7 @@ private:
     std::array<CameraConfig, NumCameras> cameras;
     std::array<PortConfig, 2> ports;
     Core::TimingEventType* completion_event_callback;
+    Core::TimingEventType* vsync_interrupt_event_callback;
     std::atomic<bool> is_camera_reload_pending{false};
 };
 

src/core/hle/service/cam/cam_c.cpp

@@ -50,7 +50,7 @@ CAM_C::CAM_C(std::shared_ptr<Module> cam) : Module::Interface(std::move(cam), "c
         {0x00270140, nullptr, "SetAutoWhiteBalanceWindow"},
         {0x00280080, nullptr, "SetNoiseFilter"},
         {0x00290080, &CAM_C::SynchronizeVsyncTiming, "SynchronizeVsyncTiming"},
-        {0x002A0080, nullptr, "GetLatestVsyncTiming"},
+        {0x002A0080, &CAM_C::GetLatestVsyncTiming, "GetLatestVsyncTiming"},
         {0x002B0000, &CAM_C::GetStereoCameraCalibrationData, "GetStereoCameraCalibrationData"},
         {0x002C0400, nullptr, "SetStereoCameraCalibrationData"},
         {0x002D00C0, nullptr, "WriteRegisterI2c"},

src/core/hle/service/cam/cam_s.cpp

@@ -50,7 +50,7 @@ CAM_S::CAM_S(std::shared_ptr<Module> cam) : Module::Interface(std::move(cam), "c
         {0x00270140, nullptr, "SetAutoWhiteBalanceWindow"},
         {0x00280080, nullptr, "SetNoiseFilter"},
         {0x00290080, &CAM_S::SynchronizeVsyncTiming, "SynchronizeVsyncTiming"},
-        {0x002A0080, nullptr, "GetLatestVsyncTiming"},
+        {0x002A0080, &CAM_S::GetLatestVsyncTiming, "GetLatestVsyncTiming"},
         {0x002B0000, &CAM_S::GetStereoCameraCalibrationData, "GetStereoCameraCalibrationData"},
         {0x002C0400, nullptr, "SetStereoCameraCalibrationData"},
         {0x002D00C0, nullptr, "WriteRegisterI2c"},

src/core/hle/service/cam/cam_u.cpp

@@ -50,7 +50,7 @@ CAM_U::CAM_U(std::shared_ptr<Module> cam) : Module::Interface(std::move(cam), "c
         {0x00270140, nullptr, "SetAutoWhiteBalanceWindow"},
         {0x00280080, nullptr, "SetNoiseFilter"},
         {0x00290080, &CAM_U::SynchronizeVsyncTiming, "SynchronizeVsyncTiming"},
-        {0x002A0080, nullptr, "GetLatestVsyncTiming"},
+        {0x002A0080, &CAM_U::GetLatestVsyncTiming, "GetLatestVsyncTiming"},
         {0x002B0000, &CAM_U::GetStereoCameraCalibrationData, "GetStereoCameraCalibrationData"},
         {0x002C0400, nullptr, "SetStereoCameraCalibrationData"},
         {0x002D00C0, nullptr, "WriteRegisterI2c"},