1 files changed, 92 insertions, 0 deletions
diff --git a/src/core/hle/kernel/k_hardware_timer_base.h b/src/core/hle/kernel/k_hardware_timer_base.h
new file mode 100644
index 000000000..6318b35bd
--- /dev/null
+++ b/src/core/hle/kernel/k_hardware_timer_base.h
@@ -0,0 +1,92 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include "core/hle/kernel/k_spin_lock.h"
+#include "core/hle/kernel/k_thread.h"
+#include "core/hle/kernel/k_timer_task.h"
+
+namespace Kernel {
+
+class KHardwareTimerBase {
+public:
+    explicit KHardwareTimerBase(KernelCore& kernel) : m_kernel{kernel} {}
+
+    void CancelTask(KTimerTask* task) {
+        KScopedDisableDispatch dd{m_kernel};
+        KScopedSpinLock lk{m_lock};
+
+        if (const s64 task_time = task->GetTime(); task_time > 0) {
+            this->RemoveTaskFromTree(task);
+        }
+    }
+
+protected:
+    KSpinLock& GetLock() {
+        return m_lock;
+    }
+
+    s64 DoInterruptTaskImpl(s64 cur_time) {
+        // We want to handle all tasks, returning the next time that a task is scheduled.
+        while (true) {
+            // Get the next task. If there isn't one, return 0.
+            KTimerTask* task = m_next_task;
+            if (task == nullptr) {
+                return 0;
+            }
+
+            // If the task needs to be done in the future, do it in the future and not now.
+            if (const s64 task_time = task->GetTime(); task_time > cur_time) {
+                return task_time;
+            }
+
+            // Remove the task from the tree of tasks, and update our next task.
+            this->RemoveTaskFromTree(task);
+
+            // Handle the task.
+            task->OnTimer();
+        }
+    }
+
+    bool RegisterAbsoluteTaskImpl(KTimerTask* task, s64 task_time) {
+        ASSERT(task_time > 0);
+
+        // Set the task's time, and insert it into our tree.
+        task->SetTime(task_time);
+        m_task_tree.insert(*task);
+
+        // Update our next task if relevant.
+        if (m_next_task != nullptr && m_next_task->GetTime() <= task_time) {
+            return false;
+        }
+        m_next_task = task;
+        return true;
+    }
+
+private:
+    void RemoveTaskFromTree(KTimerTask* task) {
+        // Erase from the tree.
+        auto it = m_task_tree.erase(m_task_tree.iterator_to(*task));
+
+        // Clear the task's scheduled time.
+        task->SetTime(0);
+
+        // Update our next task if relevant.
+        if (m_next_task == task) {
+            m_next_task = (it != m_task_tree.end()) ? std::addressof(*it) : nullptr;
+        }
+    }
+
+protected:
+    KernelCore& m_kernel;
+
+private:
+    using TimerTaskTree = Common::IntrusiveRedBlackTreeBaseTraits<KTimerTask>::TreeType<KTimerTask>;
+
+    KSpinLock m_lock{};
+    TimerTaskTree m_task_tree{};
+    KTimerTask* m_next_task{};
+};
+
+} // namespace Kernel