From ab12b5a5d4a637907bdf9ea91f1b23b726475484 Mon Sep 17 00:00:00 2001
From: Mahyar Koshkouei <mk@deltabeard.com>
Date: Sat, 2 Apr 2022 12:00:40 +0100
Subject: [PATCH] GB: Add audio processing

Signed-off-by: Mahyar Koshkouei <mk@deltabeard.com>
---
 CMakeLists.txt  |  7 +++----
 inc/peanut_gb.h |  5 ++++-
 src/main.c      | 25 ++++++++++++++++++-------
 3 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b6e3493..b7dcd21 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -8,11 +8,10 @@ project(RP2040_GB C CXX)
 # Initialize the Raspberry Pi Pico SDK
 pico_sdk_init()
 
-add_executable(RP2040_GB src/main.c src/rom.c src/mk_ili9225.c)
-target_include_directories(RP2040_GB PRIVATE inc)
+add_executable(RP2040_GB src/main.c src/rom.c src/mk_ili9225.c ext/minigb_apu/minigb_apu.c)
+target_include_directories(RP2040_GB PRIVATE inc ext/minigb_apu)
 target_link_libraries(RP2040_GB
-        pico_stdlib pico_stdio pico_bootrom pico_multicore pico_stdio
-	pico_multicore
+        pico_stdlib pico_stdio pico_bootrom pico_multicore pico_stdio  pico_multicore
         hardware_clocks hardware_pio hardware_vreg hardware_pio
         hardware_sync hardware_pll hardware_spi hardware_irq hardware_dma
         pico_binary_info)
diff --git a/inc/peanut_gb.h b/inc/peanut_gb.h
index de43b18..7dbd09d 100644
--- a/inc/peanut_gb.h
+++ b/inc/peanut_gb.h
@@ -31,6 +31,9 @@
 
 #pragma once
 
+#include "hedley.h"
+#include "minigb_apu.h"
+
 #include <stdint.h>	/* Required for int types */
 #include <string.h>	/* Required for memset */
 #include <time.h>	/* Required for tm struct */
@@ -3371,7 +3374,7 @@ void __gb_step_cpu(struct gb_s *gb)
 	}
 
 	/* Check serial transmission. */
-	if(gb->gb_reg.SC & SERIAL_SC_TX_START)
+	if(HEDLEY_UNLIKELY(gb->gb_reg.SC & SERIAL_SC_TX_START))
 	{
 		/* If new transfer, call TX function. */
 		if(gb->counter.serial_count == 0 && gb->gb_serial_tx != NULL)
diff --git a/src/main.c b/src/main.c
index 80e9cc0..8319543 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,8 +1,10 @@
-#include <sys/cdefs.h>
 
 #define ENABLE_LCD	1
-#define ENABLE_SOUND	0
+#define ENABLE_SOUND	1
+#define ENABLE_HIPASS	0
 #define USE_DMA		0
+//#define AUDIO_SAMPLE_RATE 8000.0
+//#define AUDIO_NSAMPLES	268
 
 /**
  * Reducing VSYNC calculation to lower multiple.
@@ -16,6 +18,7 @@
 
 /* C Headers */
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 
 /* RP2040 Headers */
@@ -29,7 +32,6 @@
 #include <pico/stdio.h>
 #include <pico/stdlib.h>
 #include <pico/multicore.h>
-#include <stdlib.h>
 
 /* Project headers */
 #include "hedley.h"
@@ -310,10 +312,10 @@ int main(void)
 	gpio_set_slew_rate(GPIO_SDA, GPIO_SLEW_RATE_FAST);
 
 	/* Set SPI clock to use high frequency. */
-	//clock_configure(clk_peri, 0,
-	//		CLOCKS_CLK_PERI_CTRL_AUXSRC_VALUE_CLK_SYS,
-	//		125 * 1000 * 1000, 125 * 1000 * 1000);
-	spi_init(spi0, 24*1000*1000);
+	clock_configure(clk_peri, 0,
+			CLOCKS_CLK_PERI_CTRL_AUXSRC_VALUE_CLK_SYS,
+			125 * 1000 * 1000, 125 * 1000 * 1000);
+	spi_init(spi0, 32*1000*1000);
 	spi_set_format(spi0, 16, SPI_CPOL_0, SPI_CPHA_0, SPI_MSB_FIRST);
 
 	/* Start Core1, which processes requests to the LCD. */
@@ -335,12 +337,18 @@ int main(void)
 	gb_init_lcd(&gb, &lcd_draw_line);
 	//gb.direct.interlace = 1;
 #endif
+#if ENABLE_SOUND
+	audio_init();
+#endif
 
 	uint_fast32_t frames = 0;
 	uint64_t start_time = time_us_64();
 	while(1)
 	{
 		int input;
+#if ENABLE_SOUND
+		static float stream[AUDIO_NSAMPLES];
+#endif
 
 		gb.gb_frame = 0;
 
@@ -350,6 +358,9 @@ int main(void)
 		} while(HEDLEY_LIKELY(gb.gb_frame == 0));
 
 		frames++;
+#if ENABLE_SOUND
+		audio_callback(NULL, stream, AUDIO_NSAMPLES);
+#endif
 
 		/* Required since we do not know whether a button remains
 		 * pressed over a serial connection. */