Vendor Teakra, make emulator own DSP RAM and add DSP RAM to fastmem (#806)

* DSP: Own DSP RAM and add it to fastmem

* Vendor Teakra

* Add MacOS support to fastmem

* Fix MacOS fastmem paths

* Fix iOS build

third_party/teakra/src/btdmp.h

@@ -0,0 +1,99 @@
+#pragma once
+#include <array>
+#include <cstdio>
+#include <functional>
+#include <utility>
+#include <queue>
+#include "common_types.h"
+#include "core_timing.h"
+
+namespace Teakra {
+
+class Btdmp : public CoreTiming::Callbacks {
+public:
+    Btdmp(CoreTiming& core_timing);
+    ~Btdmp();
+
+    void Reset();
+
+    void SetTransmitClockConfig(u16 value) {
+        transmit_clock_config = value;
+    }
+
+    u16 GetTransmitClockConfig() const {
+        return transmit_clock_config;
+    }
+
+    void SetTransmitPeriod(u16 value) {
+        transmit_period = value;
+    }
+
+    u16 GetTransmitPeriod() const {
+        return transmit_period;
+    }
+
+    void SetTransmitEnable(u16 value) {
+        transmit_enable = value;
+    }
+
+    u16 GetTransmitEnable() const {
+        return transmit_enable;
+    }
+
+    u16 GetTransmitEmpty() const {
+        return transmit_empty;
+    }
+
+    u16 GetTransmitFull() const {
+        return transmit_full;
+    }
+
+    void Send(u16 value) {
+        if (transmit_queue.size() == 16) {
+            std::printf("BTDMP: transmit buffer overrun\n");
+        } else {
+            transmit_queue.push(value);
+            transmit_empty = false;
+            transmit_full = transmit_queue.size() == 16;
+        }
+    }
+
+    void SetTransmitFlush(u16 value) {
+        transmit_queue = {};
+        transmit_empty = true;
+        transmit_full = false;
+    }
+
+    u16 GetTransmitFlush() const {
+        return 0;
+    }
+
+    void Tick() override;
+    u64 GetMaxSkip() const override;
+    void Skip(u64 ticks) override;
+
+    void SetAudioCallback(std::function<void(std::array<std::int16_t, 2>)> callback) {
+        audio_callback = std::move(callback);
+    }
+
+    void SetInterruptHandler(std::function<void()> handler) {
+        interrupt_handler = std::move(handler);
+    }
+
+private:
+    // TODO: figure out the relation between clock_config and period.
+    // Default to period = 4096 for now which every game uses
+    u16 transmit_clock_config = 0;
+    u16 transmit_period = 4096;
+    u16 transmit_timer = 0;
+    u16 transmit_enable = 0;
+    bool transmit_empty = true;
+    bool transmit_full = false;
+    std::queue<u16> transmit_queue;
+    std::function<void(std::array<std::int16_t, 2>)> audio_callback;
+    std::function<void()> interrupt_handler;
+
+    class BtdmpTimingCallbacks;
+};
+
+} // namespace Teakra