Implement DMA push method for sound.

CMakeLists.txt

@@ -7,6 +7,9 @@ set(CMAKE_INCLUDE_CURRENT_DIR ON)
 set(EXECUTABLE_OUTPUT_PATH ${CMAKE_BINARY_DIR}/bin)
 set(LIBRARY_OUTPUT_PATH ${CMAKE_BINARY_DIR}/lib)
 
+find_package(SDL2 REQUIRED)
+include_directories(${SDL2_INCLUDE_DIRS})
+
 add_subdirectory("${PROJECT_SOURCE_DIR}/cpu/ppc/")
 add_subdirectory("${PROJECT_SOURCE_DIR}/devices/")
 add_subdirectory("${PROJECT_SOURCE_DIR}/machines/")
@@ -15,7 +18,8 @@ add_subdirectory("${PROJECT_SOURCE_DIR}/thirdparty/")
 include_directories("${PROJECT_SOURCE_DIR}" "${PROJECT_SOURCE_DIR}/devices"
                     "${PROJECT_SOURCE_DIR}/cpu/ppc"
                     "${PROJECT_SOURCE_DIR}/debugger"
-					"${PROJECT_SOURCE_DIR}/thirdparty")
+					"${PROJECT_SOURCE_DIR}/thirdparty"
+                    ${SDL2_LIBRARIES})
 
 file(GLOB SOURCES "${PROJECT_SOURCE_DIR}/*.cpp"
                   "${PROJECT_SOURCE_DIR}/debugger/*.cpp")
@@ -27,11 +31,15 @@ add_executable(dingusppc ${SOURCES} $<TARGET_OBJECTS:cpu_ppc>
                                     $<TARGET_OBJECTS:machines>
                                     $<TARGET_OBJECTS:loguru>)
 
+target_link_libraries(dingusppc ${SDL2_LIBRARIES})
+
 add_executable(testppc ${TEST_SOURCES} $<TARGET_OBJECTS:cpu_ppc>
                                        $<TARGET_OBJECTS:devices>
                                        $<TARGET_OBJECTS:machines>
                                        $<TARGET_OBJECTS:loguru>)
 
+target_link_libraries(testppc ${SDL2_LIBRARIES})
+
 add_custom_command(
     TARGET testppc POST_BUILD
     COMMAND ${CMAKE_COMMAND} -E copy

devices/awacs.cpp

@@ -25,8 +25,12 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
 
 #include <thirdparty/loguru.hpp>
+#include "endianswap.h"
 #include "awacs.h"
 #include "machines/machinebase.h"
+#include "SDL.h"
+
+static int awac_freqs[8] = {44100, 29400, 22050, 17640, 14700, 11025, 8820, 7350};
 
 AWACDevice::AWACDevice()
 {
@@ -40,6 +44,12 @@ AWACDevice::AWACDevice()
 AWACDevice::~AWACDevice()
 {
     delete this->audio_proc;
+
+    if (this->snd_buf)
+        delete[] this->snd_buf;
+
+    if (this->snd_out_dev)
+        SDL_CloseAudioDevice(snd_out_dev);
 }
 
 uint32_t AWACDevice::snd_ctrl_read(uint32_t offset, int size)
@@ -67,7 +77,7 @@ void AWACDevice::snd_ctrl_write(uint32_t offset, uint32_t value, int size)
 
     switch(offset) {
     case AWAC_SOUND_CTRL_REG:
-        this->snd_ctrl_reg = value;
+        this->snd_ctrl_reg = BYTESWAP_32(value);
         LOG_F(INFO, "New sound control value = 0x%X", this->snd_ctrl_reg);
         break;
     case AWAC_CODEC_CTRL_REG:
@@ -82,3 +92,77 @@ void AWACDevice::snd_ctrl_write(uint32_t offset, uint32_t value, int size)
         LOG_F(ERROR, "AWAC: unsupported register at offset 0x%X", offset);
     }
 }
+
+uint32_t AWACDevice::convert_data(const uint8_t *data, int len)
+{
+    int i;
+    uint16_t *p_in, *p_out;
+
+    if (len > this->buf_len) {
+        if (this->snd_buf)
+            delete this->snd_buf;
+        this->snd_buf = new uint8_t[len];
+        this->buf_len = len;
+    }
+
+    p_in  = (uint16_t *)data;
+    p_out = (uint16_t *)this->snd_buf;
+
+    for (i = 0; i < len; i += 8) {
+        p_out[i]   = p_in[i];
+        p_out[i+1] = p_in[i+2];
+        p_out[i+2] = p_in[i+1];
+        p_out[i+3] = p_in[i+3];
+    }
+
+    return i;
+}
+
+void AWACDevice::dma_start()
+{
+    SDL_AudioSpec snd_spec, snd_settings;
+
+    SDL_zero(snd_spec);
+    snd_spec.freq = awac_freqs[(this->snd_ctrl_reg >> 8) & 7];
+    snd_spec.format = AUDIO_S16MSB; /* yes, AWAC accepts big-endian data */
+    snd_spec.channels = 2;
+    snd_spec.samples = 4096; /* buffer size, chosen empirically */
+    snd_spec.callback = NULL;
+
+    this->snd_out_dev = SDL_OpenAudioDevice(NULL, 0, &snd_spec, &snd_settings, 0);
+    if (!this->snd_out_dev) {
+        LOG_F(ERROR, "Could not open sound output device, error %s", SDL_GetError());
+    } else {
+        LOG_F(INFO, "Created audio output channel, sample rate = %d", snd_spec.freq);
+        this->wake_up = true;
+    }
+}
+
+void AWACDevice::dma_end()
+{
+    if (this->snd_out_dev) {
+        SDL_CloseAudioDevice(this->snd_out_dev);
+        this->snd_out_dev = 0;
+    }
+}
+
+void AWACDevice::dma_push(uint8_t *buf, int size)
+{
+    uint32_t dst_len;
+
+    dst_len = this->convert_data(buf, size);
+    if (dst_len) {
+        if (SDL_QueueAudio(this->snd_out_dev, this->snd_buf, dst_len)) {
+            LOG_F(ERROR, "SDL_QueueAudio error: %s", SDL_GetError());
+        }
+    }
+
+    if (this->wake_up) {
+        SDL_PauseAudioDevice(this->snd_out_dev, 0); /* start audio playing */
+        this->wake_up = false;
+    }
+}
+
+void AWACDevice::dma_pull(uint8_t *buf, int size)
+{
+}

devices/awacs.h

@@ -30,6 +30,8 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 #include <cinttypes>
 #include "i2c.h"
+#include "dbdma.h"
+#include "SDL.h"
 
 /** AWAC registers offsets. */
 enum {
@@ -98,7 +100,7 @@ private:
 };
 
 
-class AWACDevice {
+class AWACDevice : public DMACallback {
 public:
     AWACDevice();
     ~AWACDevice();
@@ -106,11 +108,26 @@ public:
     uint32_t snd_ctrl_read(uint32_t offset, int size);
     void     snd_ctrl_write(uint32_t offset, uint32_t value, int size);
 
+    /* DMACallback methods */
+    void dma_start();
+    void dma_end();
+    void dma_push(uint8_t *buf, int size);
+    void dma_pull(uint8_t *buf, int size);
+
+protected:
+    uint32_t convert_data(const uint8_t *data, int len);
+
 private:
     uint32_t snd_ctrl_reg = {0};
     uint16_t control_regs[8] = {0}; /* control registers, each 12-bits wide */
     uint8_t  is_busy = 0;
     AudioProcessor *audio_proc;
+
+    SDL_AudioDeviceID snd_out_dev = 0;
+    bool wake_up = false;
+
+    uint8_t*    snd_buf = 0;
+    uint32_t    buf_len = 0;
 };
 
 

devices/dbdma.cpp

@@ -52,8 +52,9 @@ uint8_t DMAChannel::interpret_cmd()
             LOG_F(ERROR, "non-zero i/b/w not implemented");
             break;
         }
-        LOG_F(INFO, "Transfer data, addr = 0x%X, length = 0x%X",
+        this->dma_cb->dma_push(
-            cmd_struct.address, cmd_struct.req_count);
+            mmu_get_dma_mem(cmd_struct.address, cmd_struct.req_count),
+            cmd_struct.req_count);
         this->cmd_ptr += 16;
         break;
     case 1:
@@ -66,8 +67,9 @@ uint8_t DMAChannel::interpret_cmd()
             LOG_F(ERROR, "non-zero i/b/w not implemented");
             break;
         }
-        LOG_F(INFO, "Transfer data, addr = 0x%X, length = 0x%X",
+        this->dma_cb->dma_push(
-            cmd_struct.address, cmd_struct.req_count);
+            mmu_get_dma_mem(cmd_struct.address, cmd_struct.req_count),
+            cmd_struct.req_count);
         this->cmd_ptr += 16;
         break;
     case 2:
@@ -190,6 +192,8 @@ void DMAChannel::start()
 
     LOG_F(INFO, "Starting DMA channel, stat = 0x%X", this->ch_stat);
 
+    this->dma_cb->dma_start();
+
     while (this->interpret_cmd() != 7) {
     }
 }
@@ -212,4 +216,5 @@ void DMAChannel::abort()
 void DMAChannel::pause()
 {
     LOG_F(INFO, "Pausing DMA channel");
+    this->dma_cb->dma_end();
 }

devices/dbdma.h

@@ -59,9 +59,17 @@ typedef struct DMACmd {
     uint16_t    xfer_stat;
 } DMACmd;
 
+class DMACallback {
+public:
+    virtual void dma_start(void) = 0;
+    virtual void dma_end(void)   = 0;
+    virtual void dma_push(uint8_t *buf, int size) = 0;
+    virtual void dma_pull(uint8_t *buf, int size)  = 0;
+};
+
 class DMAChannel {
 public:
-    DMAChannel() = default;
+    DMAChannel(DMACallback *cb) { this->dma_cb = cb; };
     ~DMAChannel() = default;
 
     uint32_t reg_read(uint32_t offset, int size);
@@ -77,6 +85,7 @@ protected:
     void pause(void);
 
 private:
+    DMACallback *dma_cb = 0;
     uint16_t    ch_stat = 0;
     uint32_t    cmd_ptr = 0;
 };

devices/heathrow.cpp

@@ -43,7 +43,7 @@ HeathrowIC::HeathrowIC() : PCIDevice("mac-io/heathrow")
     gMachineObj->add_subdevice("ViaCuda", this->viacuda);
 
     this->screamer = new AWACDevice();
-    this->snd_out_dma = new DMAChannel();
+    this->snd_out_dma = new DMAChannel(this->screamer);
 }
 
 HeathrowIC::~HeathrowIC()

main.cpp

@@ -30,6 +30,7 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 #include "ppcemu.h"
 #include "debugger/debugger.h"
 #include "machines/machinefactory.h"
+#include "SDL.h"
 
 using namespace std;
 
@@ -71,6 +72,11 @@ int main(int argc, char **argv)
             goto bail;
         }
 
+        if (SDL_Init(SDL_INIT_AUDIO)){
+            LOG_F(ERROR, "SDL_Init error: %s", SDL_GetError());
+            goto bail;
+        }
+
         if ((checker == "1") || (checker == "realtime") || \
             (checker == "-realtime") || (checker == "/realtime")) {
             ppc_exec();