add arch atmega2560 (preliminary support)

13 files changed, 771 insertions, 0 deletions

diff --git a/include/arch/atmega2560/arch_types.h b/include/arch/atmega2560/arch_types.h
new file mode 100644
index 0000000..2e9f070
--- /dev/null
+++ b/include/arch/atmega2560/arch_types.h
@@ -0,0 +1,12 @@
+/*
+ * Copyright 2021 Daniel Friesel
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#ifndef ARCH_TYPES_H
+#define ARCH_TYPES_H
+
+typedef uint8_t native_uint_t;
+typedef int8_t native_int_t;
+
+#endif
diff --git a/include/arch/atmega2560/driver/counter.h b/include/arch/atmega2560/driver/counter.h
new file mode 100644
index 0000000..06ff73a
--- /dev/null
+++ b/include/arch/atmega2560/driver/counter.h
@@ -0,0 +1,41 @@
+/*
+ * Copyright 2021 Daniel Friesel
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#ifndef COUNTER_H
+#define COUNTER_H
+
+#include <avr/io.h>
+#include <avr/interrupt.h>
+
+typedef uint16_t counter_value_t;
+typedef uint8_t counter_overflow_t;
+
+class Counter {
+	private:
+		Counter(const Counter &copy);
+
+	public:
+		uint16_t value;
+		volatile uint8_t overflow;
+
+		Counter() : overflow(0) {}
+
+		inline void start() {
+			overflow = 0;
+			TCNT3 = 0;
+			TCCR3A = 0;
+			TCCR3B = _BV(CS10); // no prescaler
+			TIMSK3 = _BV(TOIE3);
+		}
+
+		inline void stop() {
+			TCCR3B = 0;
+			value = TCNT3;
+		}
+};
+
+extern Counter counter;
+
+#endif
diff --git a/include/arch/atmega2560/driver/gpio.h b/include/arch/atmega2560/driver/gpio.h
new file mode 100644
index 0000000..b163ea0
--- /dev/null
+++ b/include/arch/atmega2560/driver/gpio.h
@@ -0,0 +1,234 @@
+/*
+ * Copyright 2021 Daniel Friesel
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#ifndef GPIO_H
+#define GPIO_H
+
+#include <avr/io.h>
+
+class GPIO {
+	private:
+		GPIO(const GPIO &copy);
+
+	public:
+		GPIO () {}
+
+		enum Pin : unsigned char {
+			pa0 = 0,
+			pa1 = 1,
+			pa2 = 2,
+			pa3 = 3,
+			pa4 = 4,
+			pa5 = 5,
+			pa6 = 6,
+			pa7 = 7,
+			pb0 = 8,
+			pb1 = 9,
+			pb2 = 10,
+			pb3 = 11,
+			pb4 = 12,
+			pb5 = 13,
+			pb6 = 14,
+			pb7 = 15,
+			pc0 = 16,
+			pc1 = 17,
+			pc2 = 18,
+			pc3 = 19,
+			pc4 = 20,
+			pc5 = 21,
+			pc6 = 22,
+			pc7 = 23,
+			pd0 = 24,
+			pd1 = 25,
+			pd2 = 26,
+			pd3 = 27,
+			pd4 = 28,
+			pd5 = 29,
+			pd6 = 30,
+			pd7 = 31,
+			pe0 = 32,
+			pe1 = 33,
+			pe2 = 34,
+			pe3 = 35,
+			pe4 = 36,
+			pe5 = 37,
+			pe6 = 38,
+			pe7 = 39,
+			pf0 = 40,
+			pf1 = 41,
+			pf2 = 42,
+			pf3 = 43,
+			pf4 = 44,
+			pf5 = 45,
+			pf6 = 46,
+			pf7 = 47,
+			pg0 = 48,
+			pg1 = 49,
+			pg2 = 50,
+			pg3 = 51,
+			pg4 = 52,
+			pg5 = 53,
+			ph0 = 56,
+			ph1 = 57,
+			ph2 = 58,
+			ph3 = 59,
+			ph4 = 60,
+			ph5 = 61,
+			ph6 = 62,
+			ph7 = 63,
+			pj0 = 64,
+			pj1 = 65,
+			pj2 = 66,
+			pj3 = 67,
+			pj4 = 68,
+			pj5 = 69,
+			pj6 = 70,
+			pj7 = 71,
+			pk0 = 72,
+			pk1 = 73,
+			pk2 = 74,
+			pk3 = 75,
+			pk4 = 76,
+			pk5 = 77,
+			pk6 = 78,
+			pk7 = 79,
+			pl0 = 80,
+			pl1 = 81,
+			pl2 = 82,
+			pl3 = 83,
+			pl4 = 84,
+			pl5 = 85,
+			pl6 = 86,
+			pl7 = 87
+		};
+
+		inline void setup() {
+			DDRB = _BV(PB7);
+		}
+		inline volatile uint8_t * pinToPort(uint8_t pin) {
+			if (pin <= pa7) {
+				return &PORTA;
+			}
+			if (pin <= pb7) {
+				return &PORTB;
+			}
+			if (pin <= pc7) {
+				return &PORTC;
+			}
+			return &PORTD;
+		}
+		inline unsigned char pinToBitmask(uint8_t pin) {
+			return _BV(pin % 8);
+		}
+#pragma GCC diagnostic ignored "-Wunused-parameter"
+		inline void led_on(unsigned char id) {
+			PORTB |= _BV(PB7);
+		}
+		inline void led_off(unsigned char id) {
+			PORTB &= ~_BV(PB7);
+		}
+		inline void led_toggle(unsigned char id) {
+			PINB = _BV(PB7);
+		}
+		inline void input(unsigned char const pin) {
+			if (pin < 8) {
+				DDRA &= ~_BV(pin);
+			} else if (pin < 16) {
+				DDRB &= ~_BV(pin - 8);
+			} else if (pin < 24) {
+				DDRC &= ~_BV(pin - 16);
+			} else if (pin < 32) {
+				DDRD &= ~_BV(pin - 24);
+			}
+		}
+#pragma GCC diagnostic pop
+		inline void input(unsigned char const pin, unsigned char const pull) {
+			if (pin < 8) {
+				DDRA &= ~_BV(pin);
+				PORTA |= _BV(pin);
+			} else if (pin < 16) {
+				DDRB &= ~_BV(pin - 8);
+				PORTB |= _BV(pin - 8);
+			} else if (pin < 24) {
+				DDRC &= ~_BV(pin - 16);
+				PORTC |= _BV(pin - 16);
+			} else if (pin < 32) {
+				DDRD &= ~_BV(pin - 24);
+				PORTD |= _BV(pin - 24);
+			}
+		}
+		inline void output(unsigned char const pin) {
+			if (pin < 8) {
+				DDRA |= _BV(pin);
+			} else if (pin < 16) {
+				DDRB |= _BV(pin - 8);
+			} else if (pin < 24) {
+				DDRC |= _BV(pin - 16);
+			} else if (pin < 32) {
+				DDRD |= _BV(pin - 24);
+			}
+		}
+		inline void output(unsigned char const pin, unsigned char const value) {
+			if (pin < 8) {
+				PORTA = value ? (PORTA | _BV(pin)) : (PORTA & ~_BV(pin));
+				DDRA |= _BV(pin);
+			} else if (pin < 16) {
+				PORTB = value ? (PORTB | _BV(pin - 8)) : (PORTB & ~_BV(pin - 8));
+				DDRB |= _BV(pin - 8);
+			} else if (pin < 24) {
+				PORTC = value ? (PORTC | _BV(pin - 16)) : (PORTC & ~_BV(pin - 16));
+				DDRC |= _BV(pin - 16);
+			} else if (pin < 32) {
+				PORTD = value ? (PORTD | _BV(pin - 24)) : (PORTD & ~_BV(pin - 24));
+				DDRD |= _BV(pin - 24);
+			}
+		}
+		inline unsigned char read(unsigned char const pin) {
+			if (pin < 8) {
+				return (PINA & _BV(pin));
+			}
+			if (pin < 16) {
+				return (PINB & _BV(pin - 8));
+			}
+			if (pin < 24) {
+				return (PINC & _BV(pin - 16));
+			}
+			if (pin < 32) {
+				return (PIND & _BV(pin - 24));
+			}
+			return 0;
+		}
+		inline void write(unsigned char const pin, unsigned char value) {
+			if (pin < 8) {
+				if (value) {
+					PORTA |= _BV(pin);
+				} else {
+					PORTA &= ~_BV(pin);
+				}
+			} else if (pin < 16) {
+				if (value) {
+					PORTB |= _BV(pin - 8);
+				} else {
+					PORTB &= ~_BV(pin - 8);
+				}
+			} else if (pin < 24) {
+				if (value) {
+					PORTC |= _BV(pin - 16);
+				} else {
+					PORTC &= ~_BV(pin - 16);
+				}
+			} else if (pin < 32) {
+				if (value) {
+					PORTD |= _BV(pin - 24);
+				} else {
+					PORTD &= ~_BV(pin - 24);
+				}
+			}
+		}
+};
+
+extern GPIO gpio;
+
+#endif
diff --git a/include/arch/atmega2560/driver/stdout.h b/include/arch/atmega2560/driver/stdout.h
new file mode 100644
index 0000000..09b18c1
--- /dev/null
+++ b/include/arch/atmega2560/driver/stdout.h
@@ -0,0 +1,24 @@
+/*
+ * Copyright 2021 Daniel Friesel
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#ifndef STANDARDOUTPUT_H
+#define STANDARDOUTPUT_H
+
+#include "object/outputstream.h"
+
+class StandardOutput : public OutputStream {
+	private:
+		StandardOutput(const StandardOutput &copy);
+
+	public:
+		StandardOutput () {}
+		void setup();
+
+		virtual void put(char c) override;
+};
+
+extern StandardOutput kout;
+
+#endif
diff --git a/include/arch/atmega2560/driver/timer.h b/include/arch/atmega2560/driver/timer.h
new file mode 100644
index 0000000..73a8125
--- /dev/null
+++ b/include/arch/atmega2560/driver/timer.h
@@ -0,0 +1,40 @@
+/*
+ * Copyright 2021 Daniel Friesel
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#include <avr/io.h>
+#include <avr/interrupt.h>
+
+#define ON_TIMER_INTERRUPT_head ISR(TIMER0_COMPA_vect) {
+#define ON_TIMER_INTERRUPT_tail }
+
+class Timer {
+	private:
+		Timer(const Timer &copy);
+		unsigned char prescaler;
+
+	public:
+		Timer() {}
+
+		inline void setup_khz(uint16_t const frequency) {
+			OCR0A = frequency ? 255 / frequency : 1;
+			TCCR0A = _BV(WGM01);
+			prescaler = _BV(CS01) | _BV(CS00);
+		}
+		inline void setup_hz(uint16_t const frequency) {
+			OCR0A = frequency ? 255 / frequency : 1;
+			TCCR0A = _BV(WGM01);
+			prescaler = _BV(CS02) | _BV(CS00);
+		}
+		inline void start(unsigned char const interrupt) {
+			TCNT0 = 0;
+			TCCR0B = prescaler;
+			if (interrupt) {
+				TIMSK0 = _BV(OCIE0A);
+			}
+		}
+		inline void stop() { TCCR0B = 0; TIMSK0 = 0; }
+};
+
+extern Timer timer;
diff --git a/include/arch/atmega2560/driver/uptime.h b/include/arch/atmega2560/driver/uptime.h
new file mode 100644
index 0000000..621a55c
--- /dev/null
+++ b/include/arch/atmega2560/driver/uptime.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright 2021 Daniel Friesel
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#ifndef UPTIME_H
+#define UPTIME_H
+
+#include <avr/io.h>
+
+class Uptime {
+	private:
+		Uptime(const Uptime &copy);
+#ifdef TIMER_S
+		uint8_t seconds;
+#endif
+
+	public:
+#ifdef TIMER_S
+		Uptime () : seconds(0) {}
+#else
+		Uptime () {}
+#endif
+		inline uint8_t get_cycles() { return TCNT0; }
+		inline uint8_t get_us() { return TCNT2/2; }
+#ifdef TIMER_S
+		inline uint8_t get_s() { return seconds; }
+		inline void tick_s() { seconds++; }
+#endif
+};
+
+extern Uptime uptime;
+
+#endif
diff --git a/src/arch/atmega2560/Makefile.inc b/src/arch/atmega2560/Makefile.inc
new file mode 100644
index 0000000..d78db66
--- /dev/null
+++ b/src/arch/atmega2560/Makefile.inc
@@ -0,0 +1,185 @@
+# vim:ft=make
+#
+# Copyright 2021 Daniel Friesel
+#
+# SPDX-License-Identifier: BSD-2-Clause
+
+MCU = atmega2560
+SERIAL_PORT ?= /dev/ttyUSB0
+BAUD = 115200
+
+ifdef CONFIG_arch_atmega2560_cpufreq
+	cpu_freq = ${CONFIG_arch_atmega2560_cpufreq}
+endif
+
+cpu_freq ?= 16000000
+
+COMMON_FLAGS += -Werror=overflow
+COMMON_FLAGS += -mmcu=${MCU} -DMULTIPASS_ARCH_atmega2560
+COMMON_FLAGS += -DF_CPU=${cpu_freq}UL
+COMMON_FLAGS += -DMULTIPASS_ARCH_HAS_I2C
+
+ifeq (${stack_usage}, )
+	COMMON_FLAGS += -flto
+endif
+
+CC = avr-gcc
+CXX = avr-g++
+NM = avr-nm
+OBJCOPY = avr-objcopy
+OBJDUMP = avr-objdump
+
+ARCH_SHORTNAME = avr
+
+ifdef CONFIG_aspectc
+	CXX = ag++ -r build/repo.acp -v 0 --c_compiler avr-g++ -p . --Xcompiler
+endif
+
+CXX_TARGETS += src/arch/atmega2560/arch.cc
+CXX_TARGETS += src/arch/atmega2560/driver/gpio.cc
+CXX_TARGETS += src/arch/atmega2560/driver/stdout.cc
+
+# Command-line driver selection
+
+ifneq ($(findstring softi2c,${drivers}), )
+else ifneq ($(findstring i2c,${arch_drivers}), )
+	CONFIG_arch_atmega2560_driver_i2c = y
+endif
+
+ifneq ($(findstring adc,${arch_drivers}), )
+	CONFIG_arch_atmega2560_driver_adc = y
+endif
+
+ifneq ($(findstring spi,${arch_drivers}), )
+	CONFIG_arch_atmega2560_driver_spi = y
+endif
+
+ifneq ($(findstring stdin,${arch_drivers}), )
+	CONFIG_arch_atmega2560_driver_stdin = y
+endif
+
+ifneq ($(findstring timer,${arch_drivers}), )
+	CONFIG_arch_atmega2560_driver_timer = y
+endif
+
+ifneq ($(findstring counter,${arch_drivers}), )
+	CONFIG_arch_atmega2560_driver_counter = y
+endif
+
+ifneq ($(findstring neopixel,${arch_drivers}), )
+	CONFIG_arch_atmega2560_driver_neopixel = y
+endif
+
+ifeq (${timer_s}, 1)
+	CONFIG_arch_atmega2560_driver_uptime = y
+endif
+
+# Kconfig driver selection
+
+ifdef CONFIG_arch_atmega2560_driver_i2c
+	CXX_TARGETS += src/arch/atmega2560/driver/i2c.cc
+endif
+
+ifdef CONFIG_arch_atmega2560_driver_adc
+	CXX_TARGETS += src/arch/atmega2560/driver/adc.cc
+endif
+
+ifdef CONFIG_arch_atmega2560_driver_spi
+	CXX_TARGETS += src/arch/atmega2560/driver/spi.cc
+endif
+
+ifdef CONFIG_arch_atmega2560_driver_stdin
+	CXX_TARGETS += src/arch/atmega2560/driver/stdin.cc
+endif
+
+ifdef CONFIG_arch_atmega2560_driver_timer
+	CXX_TARGETS += src/arch/atmega2560/driver/timer.cc
+endif
+
+ifdef CONFIG_arch_atmega2560_driver_counter
+	CXX_TARGETS += src/arch/atmega2560/driver/counter.cc
+endif
+
+ifdef CONFIG_arch_atmega2560_driver_neopixel
+	CXX_TARGETS += src/arch/atmega2560/driver/neopixel.cc
+endif
+
+ifdef CONFIG_arch_atmega2560_driver_uptime
+	COMMON_FLAGS += -DTIMER_S
+	CXX_TARGETS += src/arch/atmega2560/driver/uptime.cc
+endif
+
+ifeq (${cpu_freq}, 16000000)
+	uart_baud = 57600
+else ifeq (${cpu_freq}, 8000000)
+	uart_baud = 38400
+else ifeq (${cpu_freq}, 4000000)
+	uart_baud = 38400
+else ifeq (${cpu_freq}, 2000000)
+	uart_baud = 19200
+else ifeq (${cpu_freq}, 1000000)
+	uart_baud = 9600
+else ifeq (${cpu_freq}, 500000)
+	uart_baud = 4800
+else ifeq (${cpu_freq}, 250000)
+	uart_baud = 2400
+else ifeq (${cpu_freq}, 125000)
+	uart_baud = 1200
+else ifeq (${cpu_freq}, 62500)
+	uart_baud = 300
+else
+	uart_baud = 9600
+endif
+
+COMMON_FLAGS += -DBAUD=${uart_baud}UL
+
+OBJECTS = ${CXX_TARGETS:.cc=.o} ${C_TARGETS:.c=.o}
+
+.cc.o:
+	${QUIET}${CXX} ${INCLUDES} ${COMMON_FLAGS} ${CXXFLAGS} -c -o $@ ${@:.o=.cc}
+
+.c.o:
+	${QUIET}${CC} ${INCLUDES} ${COMMON_FLAGS} ${CFLAGS} -c -o $@ ${@:.o=.c}
+
+build/system.elf: ${OBJECTS}
+	${QUIET}mkdir -p build
+	${QUIET}${CXX} ${COMMON_FLAGS} ${CXXFLAGS} -Wl,--gc-sections -o $@ ${OBJECTS}
+	${QUIET}avr-size --format=avr --mcu=${MCU} $@
+	${QUIET}test $$(avr-size --format=avr --mcu=${MCU} build/system.elf | fgrep Program | grep -o '[0-9.]*%' | cut -d . -f 1) -lt 100
+
+build/system.hex: build/system.elf
+	${QUIET}${OBJCOPY} -O ihex ${@:.hex=.elf} $@
+
+program: build/system.hex
+	${QUIET}avrdude -p ${MCU} -c wiring -P ${SERIAL_PORT} -b ${BAUD} -D -U flash:w:build/system.hex
+
+arch_clean:
+	${QUIET}rm -f ${OBJECTS} build/system.hex
+
+cat:
+	${QUIET}script/cat.py ${SERIAL_PORT} ${uart_baud} ${cpu_freq} 65536
+
+monitor:
+	${QUIET}screen ${SERIAL_PORT} ${uart_baud}
+
+size: build/system.elf
+	${QUIET}avr-size --format=avr --mcu=${MCU} build/system.elf | fgrep Program | perl -nE 'if (m{(\d+) bytes \(([0-9.]+%)}) { print("$$1;$$2;") }'
+	${QUIET}avr-size --format=avr --mcu=${MCU} build/system.elf | fgrep Data | perl -nE 'if (m{(\d+) bytes \(([0-9.]+%)}) { print("$$1;$$2;") }'
+	${QUIET}echo
+
+arch_help:
+	@echo "atmega2560 specific flags:"
+	@echo " SERIAL_PORT = ${SERIAL_PORT}"
+	@echo "        BAUD = ${BAUD} (only used for programming)"
+
+arch_info:
+	@echo "CPU   Freq: ${cpu_freq} Hz"
+	@echo "Timer Freq: ${timer_freq} Hz"
+	@echo "I2C   Freq: ${i2c_freq} Hz"
+	@echo "Counter Overflow: 65536/255"
+	@echo "Monitor: ${SERIAL_PORT} ${uart_baud}"
+
+attributes: build/system.elf
+	${QUIET}script/size.py avr-size text,data data,bss
+
+.PHONY: arch_clean arch_help arch_info attributes cat monitor program size
diff --git a/src/arch/atmega2560/arch.cc b/src/arch/atmega2560/arch.cc
new file mode 100644
index 0000000..9d7e101
--- /dev/null
+++ b/src/arch/atmega2560/arch.cc
@@ -0,0 +1,104 @@
+/*
+ * Copyright 2021 Daniel Friesel
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#include "arch.h"
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include <avr/wdt.h>
+#include <util/delay.h>
+
+void Arch::setup(void)
+{
+	wdt_disable();
+
+#if F_CPU == 16000000UL
+	/* default */
+#else
+#error Unsupported F_CPU
+#endif
+
+#if defined(WITH_LOOP) || defined(TIMER_S)
+	TCCR1A = 0;
+	TCCR1B = _BV(WGM12) | _BV(CS12) | _BV(CS10); // /1024
+	OCR1A = F_CPU / 1024;
+	TIMSK1 = _BV(OCIE1A);
+#endif
+
+	sei();
+}
+
+#ifdef WITH_WAKEUP
+void wakeup();
+#endif
+
+#if defined(WITH_LOOP) || defined(TIMER_S)
+
+#include "driver/uptime.h"
+
+#endif
+
+#if defined(WITH_LOOP)
+extern void loop();
+volatile char run_loop = 0;
+#endif
+
+void Arch::idle_loop(void)
+{
+	while (1) {
+		SMCR = _BV(SE);
+		asm("sleep");
+		SMCR = 0;
+		asm("wdr");
+#ifdef WITH_LOOP
+		if (run_loop) {
+			loop();
+			run_loop = 0;
+		}
+#endif
+#ifdef WITH_WAKEUP
+		wakeup();
+#endif
+	}
+}
+
+void Arch::idle(void)
+{
+	SMCR = _BV(SE);
+	asm("sleep");
+	SMCR = 0;
+	asm("wdr");
+}
+
+void Arch::delay_us(unsigned int const us)
+{
+	for (unsigned int i = 0; i < us; i++) {
+		_delay_us(1);
+	}
+}
+
+void Arch::delay_ms(unsigned int const ms)
+{
+	for (unsigned int i = 0; i < ms; i++) {
+		_delay_ms(1);
+	}
+}
+
+Arch arch;
+
+#if defined(WITH_LOOP) || defined(TIMER_S)
+
+#ifndef __acweaving
+ISR(TIMER1_COMPA_vect)
+{
+#ifdef WITH_LOOP
+	run_loop = 1;
+#endif
+#ifdef TIMER_S
+	uptime.tick_s();
+#endif
+}
+#endif
+
+#endif
diff --git a/src/arch/atmega2560/driver/counter.cc b/src/arch/atmega2560/driver/counter.cc
new file mode 100644
index 0000000..d6cde46
--- /dev/null
+++ b/src/arch/atmega2560/driver/counter.cc
@@ -0,0 +1,15 @@
+/*
+ * Copyright 2021 Daniel Friesel
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#include "driver/counter.h"
+
+Counter counter;
+
+ISR(TIMER3_OVF_vect)
+{
+	if (counter.overflow < 255) {
+		counter.overflow++;
+	}
+}
diff --git a/src/arch/atmega2560/driver/gpio.cc b/src/arch/atmega2560/driver/gpio.cc
new file mode 100644
index 0000000..60e374e
--- /dev/null
+++ b/src/arch/atmega2560/driver/gpio.cc
@@ -0,0 +1,26 @@
+/*
+ * Copyright 2021 Daniel Friesel
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#include "driver/gpio.h"
+#include <avr/io.h>
+#include <avr/interrupt.h>
+
+GPIO gpio;
+
+#ifndef __acweaving
+ISR(PCINT0_vect)
+{
+}
+
+ISR(PCINT1_vect)
+{
+}
+
+/*
+ISR(PCINT2_vect)
+{
+}
+*/
+#endif
diff --git a/src/arch/atmega2560/driver/stdout.cc b/src/arch/atmega2560/driver/stdout.cc
new file mode 100644
index 0000000..58a3e7e
--- /dev/null
+++ b/src/arch/atmega2560/driver/stdout.cc
@@ -0,0 +1,40 @@
+/*
+ * Copyright 2021 Daniel Friesel
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#include "driver/stdout.h"
+#include <avr/io.h>
+#include <avr/interrupt.h>
+
+#ifndef BAUD
+#define BAUD 115200UL
+#endif
+
+#include <util/setbaud.h>
+
+void StandardOutput::setup()
+{
+	UBRR0H = UBRRH_VALUE;
+	UBRR0L = UBRRL_VALUE;
+
+#if USE_2X
+	UCSR0A |= _BV(U2X0);
+#else
+	UCSR0A &= ~_BV(U2X0);
+#endif
+
+	UCSR0B |= _BV(RXEN0) | _BV(TXEN0);
+	UCSR0C = _BV(UCSZ01) | _BV(UCSZ00);
+}
+
+void StandardOutput::put(char c)
+{
+	while (!(UCSR0A & _BV(UDRE0)));
+	UDR0 = c;
+	if (c == '\n') {
+		put('\r');
+	}
+}
+
+StandardOutput kout;
diff --git a/src/arch/atmega2560/driver/timer.cc b/src/arch/atmega2560/driver/timer.cc
new file mode 100644
index 0000000..b6d4145
--- /dev/null
+++ b/src/arch/atmega2560/driver/timer.cc
@@ -0,0 +1,8 @@
+/*
+ * Copyright 2021 Daniel Friesel
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#include "driver/timer.h"
+
+Timer timer;
diff --git a/src/arch/atmega2560/driver/uptime.cc b/src/arch/atmega2560/driver/uptime.cc
new file mode 100644
index 0000000..7e37a7b
--- /dev/null
+++ b/src/arch/atmega2560/driver/uptime.cc
@@ -0,0 +1,8 @@
+/*
+ * Copyright 2021 Daniel Friesel
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#include "driver/uptime.h"
+
+Uptime uptime;