first attempt at porting libopencm3 to energymicro

unless sources are explicitly given, the linker scripts and make files
were copied over from the stm32/f1 port.

examples/efm32/tinygecko/Makefile.include

@@ -0,0 +1,96 @@
+##
+## This file is part of the libopencm3 project.
+##
+## Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
+## Copyright (C) 2010 Piotr Esden-Tempski <piotr@esden.net>
+## Copyright (C) 2012 chrysn <chrysn@fsfe.org>
+##
+## This program is free software: you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation, either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program.  If not, see <http://www.gnu.org/licenses/>.
+##
+
+PREFIX	?= arm-none-eabi
+#PREFIX		?= arm-elf
+CC		= $(PREFIX)-gcc
+LD		= $(PREFIX)-gcc
+OBJCOPY		= $(PREFIX)-objcopy
+OBJDUMP		= $(PREFIX)-objdump
+GDB		= $(PREFIX)-gdb
+# Uncomment this line if you want to use the installed (not local) library.
+#TOOLCHAIN_DIR := $(shell dirname `which $(CC)`)/../$(PREFIX)
+TOOLCHAIN_DIR   = ../../../../..
+CFLAGS		+= -Os -g -Wall -Wextra -I$(TOOLCHAIN_DIR)/include \
+		   -fno-common -mcpu=cortex-m3 -mthumb -msoft-float -MD -DSTM32F1
+LDSCRIPT	?= ${TOOLCHAIN_DIR}/lib/efm32/tinygecko/$(MCU).ld
+LDFLAGS		+= -lc -lnosys -L$(TOOLCHAIN_DIR)/lib/efm32/tinygecko \
+		   -T$(LDSCRIPT) -nostartfiles -Wl,--gc-sections \
+		   -mthumb -march=armv7 -mfix-cortex-m3-ldrd -msoft-float
+OBJS		+= $(BINARY).o
+
+# Be silent per default, but 'make V=1' will show all compiler calls.
+ifneq ($(V),1)
+Q := @
+NULL := 2>/dev/null
+else
+LDFLAGS += -Wl,--print-gc-sections
+endif
+
+.SUFFIXES: .elf .bin .hex .srec .list .images
+.SECONDEXPANSION:
+.SECONDARY:
+
+all: images
+
+images: $(BINARY).images
+flash: $(BINARY).flash
+
+%.images: %.bin %.hex %.srec %.list
+	@#echo "*** $* images generated ***"
+
+%.bin: %.elf
+	@#printf "  OBJCOPY $(*).bin\n"
+	$(Q)$(OBJCOPY) -Obinary $(*).elf $(*).bin
+
+%.hex: %.elf
+	@#printf "  OBJCOPY $(*).hex\n"
+	$(Q)$(OBJCOPY) -Oihex $(*).elf $(*).hex
+
+%.srec: %.elf
+	@#printf "  OBJCOPY $(*).srec\n"
+	$(Q)$(OBJCOPY) -Osrec $(*).elf $(*).srec
+
+%.list: %.elf
+	@#printf "  OBJDUMP $(*).list\n"
+	$(Q)$(OBJDUMP) -S $(*).elf > $(*).list
+
+%.elf: $(OBJS) $(LDSCRIPT) $(TOOLCHAIN_DIR)/lib/efm32/tinygecko/libopencm3_efm32tinygecko.a
+	@#printf "  LD      $(subst $(shell pwd)/,,$(@))\n"
+	$(Q)$(LD) -o $(*).elf $(OBJS) -lopencm3_efm32tinygecko $(LDFLAGS)
+
+%.o: %.c Makefile
+	@#printf "  CC      $(subst $(shell pwd)/,,$(@))\n"
+	$(Q)$(CC) $(CFLAGS) -o $@ -c $<
+
+clean:
+	$(Q)rm -f *.o
+	$(Q)rm -f *.d
+	$(Q)rm -f *.elf
+	$(Q)rm -f *.bin
+	$(Q)rm -f *.hex
+	$(Q)rm -f *.srec
+	$(Q)rm -f *.list
+
+.PHONY: images clean
+
+-include $(OBJS:.o=.d)
+

examples/efm32/tinygecko/efm32-tg-stk3300/Makefile.include

@@ -0,0 +1,25 @@
+##
+## This file is part of the libopencm3 project.
+##
+## Copyright (C) 2012 chrysn <chrysn@fsfe.org>
+##
+## This program is free software: you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation, either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program.  If not, see <http://www.gnu.org/licenses/>.
+##
+
+MCU = EFM32TG840F32
+
+# Linker scripts are always relative to the current directory. This file is
+# intended for inclusion from example subdirectories, so the Makefile.include
+# meant here would be called ../Makefile.include relative to here.
+include ../../Makefile.include

examples/efm32/tinygecko/efm32-tg-stk3300/README

@@ -0,0 +1,9 @@
+=========================
+EFM32-TG-STK3300 Examples
+=========================
+
+Examples in this directory are designed to be run on the Energy Micro EFM32
+Tiny Gecko Starter Kit, which is based on the EFM32TG840F32 MCU, has an onboard
+USB debug and power management interface, and a bunch of peripherials built in
+that demonstrate the chip's low power capabilities (LED, LCD display, light
+sensor, touch slider, LC sensor, push buttons).

examples/efm32/tinygecko/efm32-tg-stk3300/miniblink/Makefile

@@ -0,0 +1,23 @@
+##
+## This file is part of the libopencm3 project.
+##
+## Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
+##               2012 chrysn <chrysn@fsfe.org>
+##
+## This program is free software: you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation, either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program.  If not, see <http://www.gnu.org/licenses/>.
+##
+
+BINARY = miniblink
+
+include ../Makefile.include

examples/efm32/tinygecko/efm32-tg-stk3300/miniblink/README

@@ -0,0 +1,9 @@
+==========================================
+EFM32-TG-STK3300 Examples miniblink README
+==========================================
+
+This is the smallest-possible example program using libopencm3.
+
+It's intended for the EFM32-TG-STK3300 eval board. It should blink
+the user LED on the board.
+

examples/efm32/tinygecko/efm32-tg-stk3300/miniblink/miniblink.c

@@ -0,0 +1,72 @@
+/*
+ * This file is part of the libopencm3 project.
+ *
+ * Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
+ *               2012 chrysn <chrysn@fsfe.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+//#include <libopencm3/efm32/tinygecko/gpio.h>
+//
+//void gpio_setup(void)
+//{
+//	/* Enable GPIOC clock. */
+//	/* Manually: */
+//	// RCC_APB2ENR |= RCC_APB2ENR_IOPCEN;
+//	/* Using API functions: */
+//	rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_IOPCEN);
+//
+//	/* Set GPIO8 (in GPIO port C) to 'output push-pull'. */
+//	/* Manually: */
+//	// GPIOC_CRH = (GPIO_CNF_OUTPUT_PUSHPULL << (((8 - 8) * 4) + 2));
+//	// GPIOC_CRH |= (GPIO_MODE_OUTPUT_2_MHZ << ((8 - 8) * 4));
+//	/* Using API functions: */
+//	gpio_set_mode(GPIOC, GPIO_MODE_OUTPUT_2_MHZ,
+//		      GPIO_CNF_OUTPUT_PUSHPULL, GPIO8);
+//}
+
+int main(void)
+{
+//	int i;
+//
+//	gpio_setup();
+//
+//	/* Blink the LED (PC8) on the board. */
+//	while (1) {
+//		/* Manually: */
+//		// GPIOC_BSRR = GPIO8;		/* LED off */
+//		// for (i = 0; i < 800000; i++)	/* Wait a bit. */
+//		// 	__asm__("nop");
+//		// GPIOC_BRR = GPIO8;		/* LED on */
+//		// for (i = 0; i < 800000; i++)	/* Wait a bit. */
+//		// 	__asm__("nop");
+//
+//		/* Using API functions gpio_set()/gpio_clear(): */
+//		// gpio_set(GPIOC, GPIO8);	/* LED off */
+//		// for (i = 0; i < 800000; i++)	/* Wait a bit. */
+//		// 	__asm__("nop");
+//		// gpio_clear(GPIOC, GPIO8);	/* LED on */
+//		// for (i = 0; i < 800000; i++)	/* Wait a bit. */
+//		// 	__asm__("nop");
+//
+//		/* Using API function gpio_toggle(): */
+//		gpio_toggle(GPIOC, GPIO8);	/* LED on/off */
+//		for (i = 0; i < 800000; i++)	/* Wait a bit. */
+//			__asm__("nop");
+//	}
+//
+//	return 0;
+	for(;;);
+}

include/libopencm3/efm32/tinygecko/devicerevision.h

@@ -0,0 +1,26 @@
+/* this implements d0034_efm32tg_reference_manual.pdf's 7.3.4 "Device Revision"
+ * section */
+
+#ifndef LIBOPENCM3_EFM32_TINYGECKO_DEVICEREVISION_H
+#define LIBOPENCM3_EFM32_TINYGECKO_DEVICEREVISION_H
+
+#include <libopencm3/cm3/common.h>
+
+#define DEVICEREVISION_PID2 MMIO32(0xE00FFFE8)
+#define DEVICEREVISION_PID3 MMIO32(0xE00FFFEC)
+
+/* devicerevision_revision_get has a comment that would make these definitions
+ * obsolete; i'm not sure how far it is reasonable to parameterize everythin
+ * g*/
+#define DEVICEREVISION_REVISION_LENGTH 4
+#define DEVICEREVISION_REVISION_SHIFT 4
+#define DEVICEREVISION_REVISION_MASK (~(~0<<DEVICEREVISION_REVISION_LENGTH)<<DEVICEREVISION_REVISION_SHIFT) /* 0x000000f0, bits 7:4 */
+
+#define DEVICEREVISION_REVISION_A 0x00
+
+/* Read the device's hardcoded Revision. Return values can be compared against
+ * the DEVICEREVISION_REVISION_A constant, the only value given in the current
+ * specification. */
+extern u8 devicerevision_revision_get(void);
+
+#endif

include/libopencm3/efm32/tinygecko/vector.h

@@ -0,0 +1,11 @@
+/* this implements d0002_efm32_cortex-m3_reference_manual.pdf's table 1.1's "number of interrupts" line. */
+
+
+#ifndef LIBOPENCM3_EFM32_TINYGECKO_VECTOR_H
+#define LIBOPENCM3_EFM32_TINYGECKO_VECTOR_H
+
+#define EFM32_VECTOR_NIRQ 23
+
+#include "../vector.h"
+
+#endif

include/libopencm3/efm32/vector.h

@@ -0,0 +1,34 @@
+/* this implements d0002_efm32_cortex-m3_reference_manual.pdf's figure 2.2.
+ *
+ * the structure of the vector table is implemented independently of the vector
+ * table, as it can be relocated to other memory locations too.
+ *
+ * don't include this file directly; rather, include the family's vector.h
+ * file, which defines the number of interrupts (EFM_VECTOR_NIRQ) from table
+ * 1.1 */
+
+#ifndef LIBOPENCM3_EFM32_VECTOR_H
+#define LIBOPENCM3_EFM32_VECTOR_H
+
+#include <libopencm3/cm3/common.h>
+
+typedef void (*efm32_vector_table_entry_t)(void);
+
+typedef struct {
+	unsigned int *initial_sp_value;
+	efm32_vector_table_entry_t reset;
+	efm32_vector_table_entry_t nmi;
+	efm32_vector_table_entry_t hard_fault;
+	efm32_vector_table_entry_t memory_manage_fault;
+	efm32_vector_table_entry_t bus_fault;
+	efm32_vector_table_entry_t usage_fault;
+	efm32_vector_table_entry_t reserved_x001c[4];
+	efm32_vector_table_entry_t sv_call;
+	efm32_vector_table_entry_t reserved_debug;
+	efm32_vector_table_entry_t reserved_x0034;
+	efm32_vector_table_entry_t pend_sv;
+	efm32_vector_table_entry_t systick;
+	efm32_vector_table_entry_t irq[EFM32_VECTOR_NIRQ];
+} efm32_vector_table_t;
+
+#endif

lib/efm32/tinygecko/EFM32TG840F32.ld

@@ -0,0 +1,15 @@
+/* lengths from d011_efm32tg840_datasheet.pdf table 1.1, offset from
+ * d0034_efm32tg_reference_manual.pdf figure 5.2.
+ *
+ * the origins and memory structure are constant over all tinygeckos, but the
+ * MEMORY section requires the use of constants, and has thus to be duplicated
+ * over the chip variants.
+ * */
+
+MEMORY
+{
+	rom (rx) : ORIGIN = 0, LENGTH = 32k
+	ram (rwx) : ORIGIN = 0x20000000, LENGTH = 4k
+}
+
+INCLUDE tinygecko.ld;

lib/efm32/tinygecko/Makefile

@@ -0,0 +1,59 @@
+##
+## This file is part of the libopencm3 project.
+##
+## Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
+## Copyright (C) 2012 chrysn <chrysn@fsfe.org>
+##
+## This program is free software: you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation, either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program.  If not, see <http://www.gnu.org/licenses/>.
+##
+
+LIBNAME		= libopencm3_efm32tinygecko
+
+PREFIX		?= arm-none-eabi
+#PREFIX		?= arm-elf
+CC		= $(PREFIX)-gcc
+AR		= $(PREFIX)-ar
+CFLAGS		= -Os -g -Wall -Wextra -I../../../include -fno-common \
+		  -mcpu=cortex-m3 -mthumb -Wstrict-prototypes \
+		  -ffunction-sections -fdata-sections -MD -DSTM32F1
+# ARFLAGS	= rcsv
+ARFLAGS		= rcs
+OBJS		= vector.o devicerevision.o
+
+VPATH += ../
+
+# Be silent per default, but 'make V=1' will show all compiler calls.
+ifneq ($(V),1)
+Q := @
+endif
+
+all: $(LIBNAME).a
+
+$(LIBNAME).a: $(OBJS)
+	@printf "  AR      $(subst $(shell pwd)/,,$(@))\n"
+	$(Q)$(AR) $(ARFLAGS) $@ $^
+
+%.o: %.c
+	@printf "  CC      $(subst $(shell pwd)/,,$(@))\n"
+	$(Q)$(CC) $(CFLAGS) -o $@ -c $<
+
+clean:
+	@printf "  CLEAN   lib/efm32/tinygecko\n"
+	$(Q)rm -f *.o *.d
+	$(Q)rm -f $(LIBNAME).a
+
+.PHONY: clean
+
+-include $(OBJS:.o=.d)
+

lib/efm32/tinygecko/devicerevision.c

@@ -0,0 +1,10 @@
+#include <libopencm3/efm32/tinygecko/devicerevision.h>
+
+u8 devicerevision_revision_get(void)
+{
+	/* probably this is more elegant, more readable and closer to the spec,
+	 * and i'll just get used to doing things like that:
+	return (DEVICEREVISION_PID2 & 0xf0) | ((DEVICEREVISION_PID3 & 0xf0) >> 4);
+	*/
+	return ((DEVICEREVISION_PID2 & DEVICEREVISION_REVISION_MASK) >> DEVICEREVISION_REVISION_SHIFT << DEVICEREVISION_REVISION_LENGTH) | ((DEVICEREVISION_PID3 & DEVICEREVISION_REVISION_MASK) >> DEVICEREVISION_REVISION_SHIFT);
+}

lib/efm32/tinygecko/tinygecko.ld

@@ -0,0 +1,78 @@
+/*
+ * This file is part of the libopencm3 project.
+ *
+ * Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>,
+ *               2012 chrysn <chrysn@fsfe.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/* Generic linker script for EFM32 targets using libopencm3. */
+
+/* Memory regions must be defined in the ld script which includes this one. */
+
+/* Enforce emmition of the vector table. */
+EXTERN (vector_table)
+
+/* Define the entry point of the output file. */
+ENTRY(reset_handler)
+
+/* Define sections. */
+SECTIONS
+{
+	. = ORIGIN(rom);
+
+	.text : {
+		*(.vectors)	/* Vector table */
+		*(.text*)	/* Program code */
+		. = ALIGN(4);
+		*(.rodata*)	/* Read-only data */
+		. = ALIGN(4);
+		_etext = .;
+	} >rom
+
+	. = ORIGIN(ram);
+
+	.data : AT(_etext) {
+		_data = .;
+		*(.data*)	/* Read-write initialized data */
+		. = ALIGN(4);
+		_edata = .;
+	} >ram
+
+	.bss : {
+		*(.bss*)	/* Read-write zero initialized data */
+		*(COMMON)
+		. = ALIGN(4);
+		_ebss = .;
+	} >ram AT >rom
+
+	/*
+	 * The .eh_frame section appears to be used for C++ exception handling.
+	 * You may need to fix this if you're using C++.
+	 */
+	/DISCARD/ : { *(.eh_frame) }
+
+	/*
+	 * Another section used by C++ stuff, appears when using newlib with
+	 * 64bit (long long) printf support - discard it for now.
+	 */
+	/DISCARD/ : { *(.ARM.exidx) }
+
+	. = ALIGN(4);
+	end = .;
+}
+
+PROVIDE(_stack = ORIGIN(ram) + LENGTH(ram));
+

lib/efm32/tinygecko/vector.c

@@ -0,0 +1,92 @@
+/*
+ * This file is part of the libopencm3 project.
+ *
+ * Copyright (C) 2010 Piotr Esden-Tempski <piotr@esden.net>,
+ *               2012 chrysn <chrysn@fsfe.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <libopencm3/efm32/tinygecko/vector.h>
+
+#define WEAK __attribute__ ((weak))
+
+/* Symbols exported by the linker script(s). */
+extern unsigned _etext, _data, _edata, _ebss, _stack;
+
+void main(void);
+void reset_handler(void);
+void blocking_handler(void);
+void null_handler(void);
+
+void WEAK nmi_handler(void);
+void WEAK hard_fault_handler(void);
+void WEAK mem_manage_handler(void);
+void WEAK bus_fault_handler(void);
+void WEAK usage_fault_handler(void);
+void WEAK sv_call_handler(void);
+void WEAK debug_monitor_handler(void);
+void WEAK pend_sv_handler(void);
+void WEAK sys_tick_handler(void);
+
+
+__attribute__ ((section(".vectors")))
+efm32_vector_table_t vector_table = {
+	.initial_sp_value = &_stack,
+	.reset = reset_handler,
+	.nmi = nmi_handler,
+	.hard_fault = hard_fault_handler,
+	.memory_manage_fault = mem_manage_handler,
+	.bus_fault = bus_fault_handler,
+	.usage_fault = usage_fault_handler,
+	.sv_call = sv_call_handler,
+	.pend_sv = pend_sv_handler,
+	.systick = sys_tick_handler,
+};
+
+void reset_handler(void)
+{
+	volatile unsigned *src, *dest;
+
+	__asm__("MSR msp, %0" : : "r"(&_stack));
+
+	for (src = &_etext, dest = &_data; dest < &_edata; src++, dest++)
+		*dest = *src;
+
+	while (dest < &_ebss)
+		*dest++ = 0;
+
+	/* Call the application's entry point. */
+	main();
+}
+
+void blocking_handler(void)
+{
+	while (1) ;
+}
+
+void null_handler(void)
+{
+	/* Do nothing. */
+}
+
+#pragma weak nmi_handler = null_handler
+#pragma weak hard_fault_handler = blocking_handler
+#pragma weak mem_manage_handler = blocking_handler
+#pragma weak bus_fault_handler = blocking_handler
+#pragma weak usage_fault_handler = blocking_handler
+#pragma weak sv_call_handler = null_handler
+#pragma weak debug_monitor_handler = null_handler
+#pragma weak pend_sv_handler = null_handler
+#pragma weak sys_tick_handler = null_handler