Support added for the Raspberry Pi - talking directly to the graphics co-processor.

5 files changed, 165 insertions, 0 deletions

diff --git a/boards/base/RaspberryPi/board.mk b/boards/base/RaspberryPi/board.mk
new file mode 100644
index 00000000..99fc64db
--- /dev/null
+++ b/boards/base/RaspberryPi/board.mk
@@ -0,0 +1,4 @@
+GFXINC  += $(GFXLIB)/boards/base/RaspberryPi
+GFXSRC  += $(GFXLIB)/boards/base/RaspberryPi/rpi_mailbox.c
+
+include $(GFXLIB)/drivers/gdisp/framebuffer/driver.mk
diff --git a/boards/base/RaspberryPi/board_framebuffer.h b/boards/base/RaspberryPi/board_framebuffer.h
new file mode 100644
index 00000000..eeefeb06
--- /dev/null
+++ b/boards/base/RaspberryPi/board_framebuffer.h
@@ -0,0 +1,89 @@
+/*
+ * This file is subject to the terms of the GFX License. If a copy of
+ * the license was not distributed with this file, you can obtain one at:
+ *
+ *              http://ugfx.org/license.html
+ */
+
+
+// Set this to your frame buffer pixel format and size. You can also override these in your makefile.
+#ifndef GDISP_LLD_PIXELFORMAT
+	#define GDISP_LLD_PIXELFORMAT		GDISP_PIXELFORMAT_RGB565
+#endif
+#ifndef GDISP_SCREEN_WIDTH
+	#define GDISP_SCREEN_WIDTH			800
+#endif
+#ifndef GDISP_SCREEN_HEIGHT
+	#define GDISP_SCREEN_HEIGHT			600
+#endif
+
+#ifdef GDISP_DRIVER_VMT
+
+	#if GDISP_SCREEN_WIDTH > 4096 || GDISP_SCREEN_HEIGHT > 4096
+		#error "Raspberry Pi Framebuffer: Screen size is defined too large. Max is 4096x4096"
+	#endif
+
+	#include "rpi_mailbox.h"
+
+	typedef struct FrameBufferDescription {
+		uint32_t	width;
+		uint32_t	height;
+		uint32_t	vWidth;
+		uint32_t	vHeight;
+		uint32_t	pitch;
+		uint32_t	bitDepth;
+		uint32_t	x;
+		uint32_t	y;
+		void *		pointer;
+		uint32_t	size;
+		} FrameBufferDescription;
+
+	static FrameBufferDescription FrameBufferInfo __attribute__((aligned (16))) = { 1024, 768, 1024, 768, 0, 24, 0, 0, 0, 0 };
+
+	static void board_init(GDisplay *g, fbInfo *fbi) {
+		// Initialize the Raspberry Pi frame buffer
+
+		FrameBufferInfo.width = GDISP_SCREEN_WIDTH;
+		FrameBufferInfo.height = GDISP_SCREEN_HEIGHT;
+		FrameBufferInfo.vWidth = GDISP_SCREEN_WIDTH;
+		FrameBufferInfo.vHeight = GDISP_SCREEN_HEIGHT;
+		FrameBufferInfo.bitDepth = LLDCOLOR_BITS;
+
+		rpi_writemailbox(1, 0x40000000 + (uint32_t) &FrameBufferInfo);
+
+		if (rpi_readmailbox(1) != 0)
+			gfxHalt("Could not set display parameters")
+	
+		// Set the details of the frame buffer
+		g->g.Width = GDISP_SCREEN_WIDTH;
+		g->g.Height = GDISP_SCREEN_HEIGHT;
+		g->g.Backlight = 100;
+		g->g.Contrast = 50;
+		fbi->linelen = g->g.Width * sizeof(LLDCOLOR_TYPE);	// bytes per row
+		fbi->pixels = FrameBufferInfo.pointer;				// pointer to the memory frame buffer
+	}
+
+	#if GDISP_HARDWARE_FLUSH
+		static void board_flush(GDisplay *g) {
+			(void) g;
+		}
+	#endif
+
+	#if GDISP_NEED_CONTROL
+		static void board_backlight(GDisplay *g, uint8_t percent) {
+			(void) g;
+			(void) percent;
+		}
+
+		static void board_contrast(GDisplay *g, uint8_t percent) {
+			(void) g;
+			(void) percent;
+		}
+
+		static void board_power(GDisplay *g, powermode_t pwr) {
+			(void) g;
+			(void) pwr;
+		}
+	#endif
+
+#endif /* GDISP_DRIVER_VMT */
diff --git a/boards/base/RaspberryPi/readme.txt b/boards/base/RaspberryPi/readme.txt
new file mode 100644
index 00000000..d4a59bf2
--- /dev/null
+++ b/boards/base/RaspberryPi/readme.txt
@@ -0,0 +1,18 @@
+This directory contains the interface for the Raspberry Pi framebuffer.
+This talks directly to the raspberry pi hardware (not via a linux framebuffer driver).
+
+This graphics interface is software driven - it is not an accelerated interface.
+
+This board definition should work on any operating system that will work on the Raspberry Pi
+	eg. Linux, FreeRTOS.
+
+On this board uGFX currently supports:
+	- GDISP via the framebuffer driver 
+
+THe following variables may optionally be defined in your gfxconf.h or your makefile...
+	- GDISP_LLD_PIXELFORMAT			default = GDISP_PIXELFORMAT_RGB565
+	- GDISP_SCREEN_WIDTH			default = 800
+	- GDISP_SCREEN_HEIGHT			default = 600
+
+Note that this also provides a Raspberry Pi specific api defined in rpi_mailbox.h to talk
+directly to the graphics co-processor from the ARM processor.
diff --git a/boards/base/RaspberryPi/rpi_mailbox.c b/boards/base/RaspberryPi/rpi_mailbox.c
new file mode 100644
index 00000000..798cbb1f
--- /dev/null
+++ b/boards/base/RaspberryPi/rpi_mailbox.c
@@ -0,0 +1,47 @@
+/*
+ * Access system mailboxes
+ */
+#include "rpi_mailbox.h"
+
+/* Mailbox memory addresses */
+static volatile unsigned int *MAILBOX0READ = (unsigned int *) (0x2000b880);
+static volatile unsigned int *MAILBOX0STATUS = (unsigned int *) (0x2000b898);
+static volatile unsigned int *MAILBOX0WRITE = (unsigned int *) (0x2000b8a0);
+
+/* Bit 31 set in status register if the write mailbox is full */
+#define MAILBOX_FULL 0x80000000
+
+/* Bit 30 set in status register if the read mailbox is empty */
+#define MAILBOX_EMPTY 0x40000000
+
+unsigned int rpi_readmailbox(unsigned int channel)
+{
+	unsigned int val;
+
+	if (channel > 15)
+		return 0xFFFFFFFF;
+
+	/* Wait for mailbox to be full */
+	while (*MAILBOX0STATUS & MAILBOX_EMPTY);
+
+	val = *MAILBOX0READ;
+
+	if ((val & 15) == channel)
+		return (val & 0xFFFFFFF0);
+	else
+		return 0xFFFFFFFF;
+}
+
+void rpi_writemailbox(unsigned int channel, unsigned int data)
+{
+	if (channel > 15)
+		return;
+
+	if (data & 0x000F)
+		return;
+
+	/* Wait for mailbox to be not full */
+	while (*MAILBOX0STATUS & MAILBOX_FULL);
+
+	*MAILBOX0WRITE = (data | channel);
+}
diff --git a/boards/base/RaspberryPi/rpi_mailbox.h b/boards/base/RaspberryPi/rpi_mailbox.h
new file mode 100644
index 00000000..f3c03a26
--- /dev/null
+++ b/boards/base/RaspberryPi/rpi_mailbox.h
@@ -0,0 +1,7 @@
+#ifndef RPI_MAILBOX_H
+#define RPI_MAILBOX_H
+
+extern unsigned int readmailbox(unsigned int channel);
+extern void writemailbox(unsigned int channel, unsigned int data);
+
+#endif	/* RPI_MAILBOX_H */