From 731bba0f0e4091eb841f024d5aa60b4de7edcb87 Mon Sep 17 00:00:00 2001
From: Attila BODY <attila.body@gmail.com>
Date: Tue, 1 Dec 2020 14:35:47 +0100
Subject: [PATCH] Alternating buffers for DMA (works only with optimization)

---
 .cproject          |  2 +-
 App/App.cpp        | 94 +++++++++++++++++++++++++++++++++++-----------
 App/Config.h       |  6 ++-
 App/LedBuffers.cpp | 13 +++++--
 App/LedBuffers.h   |  7 +++-
 App/Pixel.h        |  4 +-
 App/Sparkle.cpp    | 11 ++++--
 App/Sparkle.h      |  9 +++--
 8 files changed, 106 insertions(+), 40 deletions(-)

diff --git a/.cproject b/.cproject
index 6db3336..be429ab 100644
--- a/.cproject
+++ b/.cproject
@@ -169,7 +169,7 @@
 							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_cpuid.427092296" name="CpuId" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_cpuid" value="0" valueType="string"/>
 							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_coreid.803288303" name="CpuCoreId" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_coreid" value="0" valueType="string"/>
 							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_board.142185949" name="Board" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_board" value="genericBoard" valueType="string"/>
-							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.defaults.1897240971" name="Defaults" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.defaults" value="com.st.stm32cube.ide.common.services.build.inputs.revA.1.0.3 || Release || false || Executable || com.st.stm32cube.ide.mcu.gnu.managedbuild.toolchain.base.gnu-tools-for-stm32 || STM32F103C8Tx || 0 || 0 || arm-none-eabi- || ${gnu_tools_for_stm32_compiler_path} || ../Inc | ../Drivers/STM32F1xx_HAL_Driver/Inc | ../Drivers/STM32F1xx_HAL_Driver/Inc/Legacy | ../Drivers/CMSIS/Device/ST/STM32F1xx/Include | ../Drivers/CMSIS/Include ||  ||  || USE_HAL_DRIVER | STM32F103xB ||  || Drivers | Src | Startup ||  ||  || ${workspace_loc:/${ProjName}/STM32F103C8TX_FLASH.ld} || true || NonSecure ||  || secure_nsclib.o || " valueType="string"/>
+							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.defaults.1897240971" name="Defaults" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.defaults" value="com.st.stm32cube.ide.common.services.build.inputs.revA.1.0.3 || Release || true || Executable || com.st.stm32cube.ide.mcu.gnu.managedbuild.toolchain.base.gnu-tools-for-stm32 || STM32F103C8Tx || 0 || 0 || arm-none-eabi- || ${gnu_tools_for_stm32_compiler_path} || ../Inc | ../Drivers/CMSIS/Device/ST/STM32F1xx/Include | ../Drivers/CMSIS/Include | ../Drivers/STM32F1xx_HAL_Driver/Inc/Legacy | ../Drivers/STM32F1xx_HAL_Driver/Inc ||  ||  || VDD_VALUE=3300 | HSE_VALUE=8000000 | STM32F103xB | LSI_VALUE=40000 | HSI_VALUE=8000000 | HSE_STARTUP_TIMEOUT=100 | USE_FULL_LL_DRIVER | LSE_STARTUP_TIMEOUT=5000 | LSE_VALUE=32768 | PREFETCH_ENABLE=1 ||  || Drivers | Src | Startup ||  ||  || ${workspace_loc:/${ProjName}/STM32F103C8TX_FLASH.ld} || true || NonSecure ||  || secure_nsclib.o || " valueType="string"/>
 							<targetPlatform archList="all" binaryParser="org.eclipse.cdt.core.ELF" id="com.st.stm32cube.ide.mcu.gnu.managedbuild.targetplatform.1774904877" isAbstract="false" osList="all" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.targetplatform"/>
 							<builder buildPath="${workspace_loc:/NeoPixelF103MVP}/Release" id="com.st.stm32cube.ide.mcu.gnu.managedbuild.builder.1500348018" keepEnvironmentInBuildfile="false" managedBuildOn="true" name="Gnu Make Builder" parallelBuildOn="true" parallelizationNumber="optimal" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.builder"/>
 							<tool id="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.assembler.2006730064" name="MCU GCC Assembler" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.assembler">
diff --git a/App/App.cpp b/App/App.cpp
index 4a586c2..f7511d1 100644
--- a/App/App.cpp
+++ b/App/App.cpp
@@ -21,8 +21,15 @@
 
 Sparkle	g_sparkles[NUMSPARKLES];
 volatile uint8_t g_spi_idle = 0;
+uint16_t g_pixels_transmitted;
+volatile uint8_t g_buffer_in_transmit;
+volatile bool g_need_refill;
+uint32_t g_refills = 0;
+uint16_t g_pixels_converted = 0;
 
-volatile uint32_t	g_tick = 0;
+volatile uint32_t g_tick = 0;
+
+#define MIN(a,b) ((a) < (b) ? (a) : (b))
 
 void convert(uint8_t *src, uint8_t *dst, uint16_t size)
 {
@@ -51,7 +58,7 @@ uint16_t ChoosePixel()
 	do {
 		chosen = rr(NUMPIXELS);
 		for(spi=0; spi<NUMSPARKLES; ++spi) {
-			if(static_cast<Pixel_t*>(g_sparkles[spi]) && static_cast<Pixel_t*>(g_sparkles[spi]) == &g_pixels[chosen])
+			if(static_cast<pixel_t*>(g_sparkles[spi]) && static_cast<pixel_t*>(g_sparkles[spi]) == &g_pixels[chosen])
 				break;
 		}
 	} while(spi < NUMSPARKLES);
@@ -63,7 +70,7 @@ uint16_t ChoosePixel()
 
 void StartSparkle( Sparkle &s )
 {
-	s.Start(g_pixels+ChoosePixel(), Pixel(255,255,255), Pixel(rr(8)+3,rr(8)+3,rr(8)+3));
+	s.Start(g_pixels+ChoosePixel(), rr(32), Pixel(255,255,255), Pixel(rr(8)+3,rr(8)+3,rr(8)+3));
 }
 
 extern "C" void HandleSystick()
@@ -78,54 +85,97 @@ extern "C" uint32_t GetTick()
 
 extern "C" void HandleSpiDmaIrq()
 {
-	if(LL_DMA_IsActiveFlag_TC3(DMA1)) {
+	static bool endframe;
+
+	if(LL_DMA_IsActiveFlag_TC3(DMA1))
+	{
 		LL_DMA_ClearFlag_TC3(DMA1);
-		g_spi_idle = true;
-		LL_SPI_DisableDMAReq_TX(SPI1);
 		LL_DMA_DisableChannel(DMA1, LL_DMA_CHANNEL_3);
-	} else if(LL_DMA_IsActiveFlag_TE3(DMA1))
+
+		g_buffer_in_transmit ^= 1;
+		g_pixels_transmitted += SPIBUFFER_PIXELS;
+
+		if(g_pixels_transmitted < NUMPIXELS)
+		{
+			LL_DMA_SetMemoryAddress(DMA1, LL_DMA_CHANNEL_3, (uint32_t)g_spibuffer[g_buffer_in_transmit]);
+			LL_DMA_SetDataLength(DMA1, LL_DMA_CHANNEL_3, SPIBUFFER_SIZE);
+			LL_DMA_EnableChannel(DMA1, LL_DMA_CHANNEL_3);
+
+			if(g_pixels_converted < NUMPIXELS)
+			{
+				LL_GPIO_TogglePin(GPIOC, LL_GPIO_PIN_13);
+				convert((uint8_t*)&g_pixels[g_pixels_converted],
+						g_spibuffer[g_buffer_in_transmit ^ 1],
+						MIN(SPIBUFFER_PIXELS, NUMPIXELS - g_pixels_converted)  * sizeof(pixel_t));
+				g_pixels_converted += MIN(SPIBUFFER_PIXELS, NUMPIXELS - g_pixels_converted);
+				LL_GPIO_TogglePin(GPIOC, LL_GPIO_PIN_13);
+				endframe = false;
+			}
+			else
+			{
+				memset(g_spibuffer[g_buffer_in_transmit ^1], 0, sizeof(g_spibuffer[g_buffer_in_transmit ^1]));
+				endframe = true;
+			}
+
+		}
+		else if(endframe)
+		{
+			LL_DMA_SetMemoryAddress(DMA1, LL_DMA_CHANNEL_3, (uint32_t)g_spibuffer[g_buffer_in_transmit]);
+			LL_DMA_SetDataLength(DMA1, LL_DMA_CHANNEL_3, SPIBUFFER_SIZE);
+			LL_DMA_EnableChannel(DMA1, LL_DMA_CHANNEL_3);
+			endframe = false;
+		}
+		else {
+			g_spi_idle = true;
+		}
+	}
+	else if(LL_DMA_IsActiveFlag_TE3(DMA1))
 		LL_DMA_ClearFlag_TE3(DMA1);
+
 }
 
 extern "C" void App()
 {
-	g_spibuffer[sizeof(g_spibuffer)-1] = 0;
+	uint32_t lastTick = GetTick();
 
 	for(uint16_t px = 0; px < NUMPIXELS; ++px)
-		g_pixels[px] = Pixel( DEFAULT_COLOR );
-
-	uint32_t lastTick = GetTick();
+		g_pixels[px] = Pixel(DEFAULT_COLOR);
 
 	LL_SYSTICK_EnableIT();
 	LL_SPI_Enable(SPI1);
+	LL_SPI_EnableDMAReq_TX(SPI1);
 
 	while(1)
 	{
 		while(GetTick() - lastTick < FRAMETIME );
 		lastTick += FRAMETIME;
-		LL_GPIO_TogglePin(GPIOC, LL_GPIO_PIN_13);
 
 		for(int16_t spi = 0; spi < NUMSPARKLES; ++spi) {
-			if(static_cast<Pixel_t*>(g_sparkles[spi]))
+			if(static_cast<pixel_t*>(g_sparkles[spi]))
 				g_sparkles[spi].Step();
 			else
 				StartSparkle(g_sparkles[spi]);
 		}
-		LL_GPIO_TogglePin(GPIOC, LL_GPIO_PIN_13);
 
-		convert((uint8_t*)g_pixels, g_spibuffer, sizeof(g_pixels));
-		LL_GPIO_TogglePin(GPIOC, LL_GPIO_PIN_13);
+		g_pixels_converted = 0;
+		g_pixels_transmitted = 0;
+		g_need_refill = true;
 
-		g_spi_idle = false;
-//		HAL_SPI_Transmit_DMA(&hspi1, g_ledBits, sizeof(g_ledBits));
-		LL_DMA_ConfigAddresses(DMA1, LL_DMA_CHANNEL_3, (uint32_t)g_spibuffer, LL_SPI_DMA_GetRegAddr(SPI1), LL_DMA_DIRECTION_MEMORY_TO_PERIPH);
-		LL_DMA_SetDataLength(DMA1, LL_DMA_CHANNEL_3, sizeof(g_spibuffer));
+		convert((uint8_t*)g_pixels, g_spibuffer[0], SPIBUFFER_PIXELS * sizeof(pixel_t));
+		g_pixels_converted += SPIBUFFER_PIXELS;
+		convert((uint8_t*)&g_pixels[g_pixels_converted], g_spibuffer[1], SPIBUFFER_PIXELS * sizeof(pixel_t));
+		g_pixels_converted += SPIBUFFER_PIXELS;
+
+		g_buffer_in_transmit = 0;
+
+		LL_DMA_ConfigAddresses(DMA1, LL_DMA_CHANNEL_3, (uint32_t)g_spibuffer[0], LL_SPI_DMA_GetRegAddr(SPI1), LL_DMA_DIRECTION_MEMORY_TO_PERIPH);
+		LL_DMA_SetDataLength(DMA1, LL_DMA_CHANNEL_3, SPIBUFFER_SIZE);
 		LL_DMA_EnableChannel(DMA1, LL_DMA_CHANNEL_3);
-		LL_SPI_EnableDMAReq_TX(SPI1);
 		LL_DMA_EnableIT_TC(DMA1, LL_DMA_CHANNEL_3);
 		LL_DMA_EnableIT_TE(DMA1, LL_DMA_CHANNEL_3);
+		g_spi_idle = false;
 
 		while(!g_spi_idle);
-		LL_GPIO_TogglePin(GPIOC, LL_GPIO_PIN_13);
+
 	}
 }
diff --git a/App/Config.h b/App/Config.h
index 31b12ce..378322c 100644
--- a/App/Config.h
+++ b/App/Config.h
@@ -13,11 +13,13 @@
 #ifndef DBG_CHOSEN_PIXEL
 #	define NUMPIXELS 144
 #	define NUMSPARKLES (NUMPIXELS/12+1)
+#	define FRAMETIME 20
 #else
 #	define NUMPIXELS 6
 #	define NUMSPARKLES 1
+#	define FRAMETIME 1
 #endif
 
-#define FRAMETIME 20
-#define DEFAULT_COLOR 0,0,0
+#define DEFAULT_COLOR 63,63,63
+#define SPIBUFFER_PIXELS 2
 #endif /* CONFIG_H_ */
diff --git a/App/LedBuffers.cpp b/App/LedBuffers.cpp
index 6268c2f..65c88b9 100644
--- a/App/LedBuffers.cpp
+++ b/App/LedBuffers.cpp
@@ -6,8 +6,13 @@
  */
 #include "LedBuffers.h"
 
-Pixel_t g_pixels[NUMPIXELS];
-uint8_t g_spibuffer[sizeof(g_pixels) * 8 / 2 + 1];
-
-
+pixel_t g_pixels[NUMPIXELS] = {
+		{0xaa,0x55,0},
+		{0x55,0xaa,0xff},
+		{0xaa,0x55,0},
+		{0x55,0xaa,0xff},
+		{0xaa,0x55,0},
+		{0x55,0xaa,0xff},
+};
 
+uint8_t g_spibuffer[2][SPIBUFFER_SIZE];
diff --git a/App/LedBuffers.h b/App/LedBuffers.h
index df32021..6db399b 100644
--- a/App/LedBuffers.h
+++ b/App/LedBuffers.h
@@ -11,7 +11,10 @@
 #include "Config.h"
 #include "Pixel.h"
 
-extern Pixel_t g_pixels[NUMPIXELS];
-extern uint8_t g_spibuffer[sizeof(g_pixels) * 8 / 2 + 1];
+extern pixel_t g_pixels[NUMPIXELS];
+
+#define SPIBUFFER_SIZE (SPIBUFFER_PIXELS * sizeof(pixel_t) * 8 / 2)
+
+extern uint8_t g_spibuffer[2][SPIBUFFER_SIZE];
 
 #endif /* LEDBUFFERS_H_ */
diff --git a/App/Pixel.h b/App/Pixel.h
index cf9ce5e..79fe085 100644
--- a/App/Pixel.h
+++ b/App/Pixel.h
@@ -18,14 +18,14 @@ typedef struct {
 	uint8_t g;
 	uint8_t r;
 	uint8_t b;
-} Pixel_t;
+} pixel_t;
 
 #ifdef __cplusplus
 }
 #endif
 
 #ifdef __cplusplus
-struct Pixel : public Pixel_t {
+struct Pixel : public pixel_t {
 	Pixel(uint8_t _r, uint8_t _g, uint8_t _b) {
 		g =_g;
 		r = _r;
diff --git a/App/Sparkle.cpp b/App/Sparkle.cpp
index eec81a6..8607069 100644
--- a/App/Sparkle.cpp
+++ b/App/Sparkle.cpp
@@ -14,16 +14,22 @@ Sparkle::Sparkle()
 Sparkle::~Sparkle() {
 }
 
-void Sparkle::Start(Pixel_t *target, Pixel_t color, Pixel_t fadeSpeed)
+void Sparkle::Start(pixel_t *target, uint8_t delay, pixel_t color, pixel_t fadeSpeed)
 {
 	m_target = target;
 	*target = color;
+	m_delay = delay;
 	m_fadeSpeed = fadeSpeed;
 }
 
 bool Sparkle::Step()
 {
-	Pixel_t current = *m_target;
+	if(m_delay) {
+		--m_delay;
+		return true;
+	}
+
+	pixel_t current = *m_target;
 	uint8_t remaining = 3;
 
 	if(current.r > m_fadeSpeed.r )current.r -= m_fadeSpeed.r;
@@ -48,5 +54,4 @@ bool Sparkle::Step()
 	if(remaining) return true;
 	m_target = nullptr;
 	return false;
-
 }
diff --git a/App/Sparkle.h b/App/Sparkle.h
index be2d191..86922a8 100644
--- a/App/Sparkle.h
+++ b/App/Sparkle.h
@@ -14,13 +14,14 @@ class Sparkle {
 public:
 	Sparkle();
 	~Sparkle();
-	void Start(Pixel_t *target, Pixel_t color, Pixel_t fadeSpeed);
+	void Start(pixel_t *target, uint8_t delay, pixel_t color, pixel_t fadeSpeed);
 	bool Step();
-	operator Pixel_t*() { return m_target; }
+	operator pixel_t*() { return m_target; }
 
 private:
-	Pixel_t		*m_target = nullptr;
-	Pixel_t		m_fadeSpeed = {1, 1, 1};
+	pixel_t		*m_target = nullptr;
+	uint8_t		m_delay;
+	pixel_t		m_fadeSpeed = {1, 1, 1};
 };
 
 #endif /* SPARKLE_H_ */