Merge pull request #24 from LudwigOrtmann/master

primitive native cpu target

Makefile.base

@@ -20,6 +20,9 @@ ifeq ($(CPU),cc430)
  INCLUDES += -I$(MAKEBASE)/cpu/msp430-common/include/
  INCLUDES += -I$(MAKEBASE)/cpu/cc430/include/
 endif
+ifeq ($(CPU),native)
+ INCLUDES += -I$(MAKEBASE)/cpu/native/include/
+endif
 ifeq ($(BOARD),msba2)
  INCLUDES += -I$(RIOTBOARD)/msba2/include/
  INCLUDES += -I$(RIOTBOARD)/msba2-common/include/

core/include/kernel_intern.h

@@ -18,7 +18,7 @@
 
 void kernel_init(void);
 void board_init_drivers(void);
-char *thread_stack_init(void  *task_func, void *stack_start);
+char *thread_stack_init(void  *task_func, void *stack_start, int stack_size);
 void sched_task_exit(void);
 void thread_print_stack (void);
 int thread_measure_stack_usage(char* stack);

core/thread.c

@@ -143,7 +143,7 @@ int thread_create(char *stack, int stacksize, char priority, int flags, void (*f
         return -EOVERFLOW;
     }
 
-    cb->sp = thread_stack_init(function,stack+stacksize);
+    cb->sp = thread_stack_init(function,stack,stacksize);
     cb->stack_start = stack;
     cb->stack_size = total_stacksize;
 

cpu/Makefile

@@ -14,6 +14,10 @@ ifeq ($(CPU),msp430x16x)
  DIRS = msp430-common msp430x16x
 endif
 
+ifeq ($(CPU),native)
+ DIRS = native
+endif
+
 .PHONY: cpus
 .PHONY: $(DIRS)
 
@@ -28,6 +32,5 @@ clean:
 	@$(MAKE) -C cc430 clean
 	@$(MAKE) -C msp430-common clean
 	@$(MAKE) -C msp430x16x clean
-
-
+	@$(MAKE) -C native clean
 

cpu/native/Makefile

@@ -0,0 +1,16 @@
+MODULE = cpu
+
+INCLUDES = -I../include -I$(RIOTBASE)/core/include
+DIRS =
+ifneq (,$(findstring rtc,$(USEMODULE)))
+	DIRS += rtc
+endif
+
+all: $(BINDIR)$(MODULE).a
+	@for i in $(DIRS) ; do $(MAKE) -C $$i ; done ;
+
+include $(RIOTBASE)/Makefile.base
+
+clean::
+	@for i in $(DIRS) ; do $(MAKE) -C $$i clean ; done ;
+

cpu/native/atomic_cpu.c

@@ -0,0 +1,35 @@
+/**
+ * Native CPU atomic.h implementation
+ *
+ * Copyright (C) 2013 Ludwig Ortmann
+ *
+ * This file subject to the terms and conditions of the GNU General Public
+ * License. See the file LICENSE in the top level directory for more details.
+ *
+ * @ingroup arch
+ * @{
+ * @file
+ * @author Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ * @}
+ */
+
+#include <atomic.h>
+#include <irq.h>
+#include <debug.h>
+
+unsigned int atomic_set_return(unsigned int* val, unsigned int set)
+{
+    unsigned int old_val;
+    unsigned int old_state;
+
+    DEBUG("atomic_set_return\n");
+
+    old_state = disableIRQ();
+
+    old_val = *val;
+    *val = set;
+
+    restoreIRQ(old_state);
+
+    return old_val;
+}

cpu/native/hwtimer_cpu.c

@@ -0,0 +1,165 @@
+/**
+ * Native CPU hwtimer_arch.h implementation
+ *
+ * Copyright (C) 2013 Ludwig Ortmann
+ *
+ * This file subject to the terms and conditions of the GNU General Public
+ * License. See the file LICENSE in the top level directory for more details.
+ *
+ * @ingroup arch
+ * @{
+ * @file
+ * @author  Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ * @}
+ */
+
+#include <time.h>
+#include <signal.h>
+#include <stdint.h>
+#include <err.h>
+#include "hwtimer.h"
+#include "hwtimer_arch.h"
+
+#include "hwtimer_cpu.h"
+#include "cpu.h"
+#include "cpu-conf.h"
+
+#include "debug.h"
+
+#define HWTIMER_MINTICKS (1000)
+
+static unsigned long native_hwtimer_now;
+static int native_hwtimer_irq[ARCH_MAXTIMERS];
+static timer_t native_hwtimer_timer[ARCH_MAXTIMERS];
+static void (*int_handler)(int);
+
+void ticks2ts(unsigned long ticks, struct timespec *tp)
+{
+   tp->tv_sec = ticks / HWTIMER_SPEED;
+   tp->tv_nsec = (ticks % HWTIMER_SPEED)*1000 ;
+}
+
+unsigned long ts2ticks(struct timespec *tp)
+{
+    /* TODO: check for overflow */
+    return((tp->tv_sec * HWTIMER_SPEED) + (tp->tv_nsec/1000));
+}
+
+void hwtimer_isr_timer()
+{
+    DEBUG("hwtimer_isr_timer()\n");
+
+    for (int i = 0; i<ARCH_MAXTIMERS; i++) {
+        if (native_hwtimer_irq[i] == 1) {
+            DEBUG("hwtimer_isr_timer(): calling hwtimer.int_handler(%i)\n", i);
+            int_handler(i);
+        }
+    }
+}
+
+void hwtimer_arch_enable_interrupt(void)
+{
+    DEBUG("hwtimer_arch_enable_interrupt()\n");
+    if (register_interrupt(SIGALRM, hwtimer_isr_timer) != 0) {
+        DEBUG("darn!\n\n");
+    }
+    return;
+}
+
+void hwtimer_arch_disable_interrupt(void)
+{
+    DEBUG("hwtimer_arch_disable_interrupt()\n");
+    if (unregister_interrupt(SIGALRM) != 0) {
+        DEBUG("darn!\n\n");
+    }
+    return;
+}
+
+void hwtimer_arch_unset(short timer)
+{
+    struct itimerspec its;
+
+    DEBUG("hwtimer_arch_unset(%d)\n", timer);
+
+    native_hwtimer_irq[timer] = 0;
+
+    its.it_interval.tv_nsec = 0;
+    its.it_interval.tv_sec = 0;
+    its.it_value.tv_nsec = 0;
+    its.it_value.tv_sec = 0;
+
+    if( (timer_settime(native_hwtimer_timer[timer], 0, &its, NULL)) == -1) {
+        err(1, "hwtimer_arch_unset: timer_settime");
+    }
+
+    return;
+}
+
+/**
+ * Set a kernel timer to raise an interrupt after ::offset kernel timer ticks
+ * from now.
+ */
+void hwtimer_arch_set(unsigned long offset, short timer)
+{
+    struct itimerspec its;
+
+    DEBUG("hwtimer_arch_set(%li, %i)\n", offset, timer);
+    native_hwtimer_irq[timer] = 1;
+
+    ticks2ts(offset, &its.it_value);
+    DEBUG("hwtimer_arch_set(): that is %lis %lins from now\n", its.it_value.tv_sec, its.it_value.tv_nsec);
+
+    its.it_interval.tv_sec = 0;
+    its.it_interval.tv_nsec = 0;
+    if (timer_settime(native_hwtimer_timer[timer], 0, &its, NULL) == -1) {
+        err(1, "hwtimer_arch_unset: timer_settime");
+    }
+
+    return;
+}
+
+void hwtimer_arch_set_absolute(unsigned long value, short timer)
+{
+    DEBUG("hwtimer_arch_set_absolute(%li, %i)\n", value, timer);
+    value -= native_hwtimer_now;
+    return(hwtimer_arch_set(value, timer));
+}
+
+unsigned long hwtimer_arch_now(void)
+{
+    struct timespec t;
+
+    DEBUG("hwtimer_arch_now()\n");
+
+    if (clock_gettime(CLOCK_MONOTONIC, &t) == -1) {
+        err(1, "hwtimer_arch_now: clock_gettime");
+    }
+    native_hwtimer_now = ts2ticks(&t);
+
+    DEBUG("hwtimer_arch_now(): it is now %lis %lins\n", t.tv_sec, t.tv_nsec);
+    DEBUG("hwtimer_arch_now(): returning %li\n", native_hwtimer_now);
+    return native_hwtimer_now;
+}
+
+void hwtimer_arch_init(void (*handler)(int), uint32_t fcpu)
+{
+    struct sigevent sev;
+
+    DEBUG("hwtimer_arch_init()\n");
+
+    hwtimer_arch_disable_interrupt();
+
+    int_handler = handler;
+
+    sev.sigev_notify = SIGEV_SIGNAL;
+    for (int i = 0; i<ARCH_MAXTIMERS; i++) {
+        native_hwtimer_irq[i] = 0;
+        //sev.sigev_signo =  _SIG_TIMER + i;;
+        sev.sigev_signo =  SIGALRM;
+        sev.sigev_value.sival_ptr = &native_hwtimer_timer[i];
+        if (timer_create(CLOCK_REALTIME, &sev, &native_hwtimer_timer[i]) == -1) {
+            err(1, "timer_create");
+        }
+    }
+    return;
+}

cpu/native/include/cpu-conf.h

@@ -0,0 +1,33 @@
+/**
+ * Native CPU configuration
+ *
+ * Copyright (C) 2013 Ludwig Ortmann
+ *
+ * This file subject to the terms and conditions of the GNU General Public
+ * License. See the file LICENSE in the top level directory for more details.
+ *
+ * @ingroup arch
+ * @{
+ * @file
+ * @author  Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ * @}
+ */
+#ifndef CPUCONF_H_
+#define CPUCONF_H_
+#include <signal.h>
+
+/* TODO: choose more sensibly? */
+#ifndef KERNEL_CONF_STACKSIZE_DEFAULT
+#define KERNEL_CONF_STACKSIZE_DEFAULT   8192
+#endif
+
+#define KERNEL_CONF_STACKSIZE_IDLE      2048
+#define NATIVE_ISR_STACKSIZE            8192
+
+#define _SIG_UNDEF          SIGRTMIN + 0
+#define _SIG_TIMER          SIGRTMIN + 10 // check hwtimer_cpu.h for compliance
+#define _SIG_LTC4150        SIGRTMIN + 20
+
+/* TODO: check for overflow (SIGRTMAX) */
+
+#endif /* CPUCONF_H_ */

cpu/native/include/cpu.h

@@ -0,0 +1,37 @@
+/**
+ * Native CPU interface
+ *
+ * Copyright (C) 2013 Ludwig Ortmann
+ *
+ * This file subject to the terms and conditions of the GNU General Public
+ * License. See the file LICENSE in the top level directory for more details.
+ *
+ * @ingroup arch
+ * @{
+ * @file
+ * @author  Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ * @}
+ */
+
+#ifndef _CPU_H
+#define _CPU_H
+
+#include <ucontext.h>
+
+#include "kernel_intern.h"
+#include "sched.h"
+#include "debug.h"
+
+#include "cpu-conf.h"
+
+/* TODO: choose better value? */
+#define F_CPU 1000000
+
+void dINT(void);
+void eINT(void);
+
+int register_interrupt(int sig, void *handler);
+int unregister_interrupt(int sig);
+void thread_yield(void);
+
+#endif //_CPU_H

cpu/native/include/hwtimer_cpu.h

@@ -0,0 +1,24 @@
+/**
+ * Native CPU hwtimer_cpu configuration
+ *
+ * Copyright (C) 2013 Ludwig Ortmann
+ *
+ * This file subject to the terms and conditions of the GNU General Public
+ * License. See the file LICENSE in the top level directory for more details.
+ *
+ * @ingroup arch
+ * @{
+ * @file
+ * @author  Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ * @}
+ */
+
+#ifndef HWTIMER_CPU_H_
+#define HWTIMER_CPU_H_
+
+/* TODO: choose more appropriate values here? */
+#define ARCH_MAXTIMERS 4
+#define HWTIMER_SPEED 1000000
+#define HWTIMER_MAXTICKS (0xFFFFFFFF)
+
+#endif /* HWTIMER_CPU_H_ */

cpu/native/irq_cpu.c

@@ -0,0 +1,271 @@
+/**
+ * Native CPU irq.h implementation
+ *
+ * Copyright (C) 2013 Ludwig Ortmann
+ *
+ * This file subject to the terms and conditions of the GNU General Public
+ * License. See the file LICENSE in the top level directory for more details.
+ *
+ * @ingroup arch
+ * @{
+ * @file
+ * @author  Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ * @}
+ */
+#include <signal.h>
+#include <err.h>
+
+#include <irq.h>
+#include "cpu.h"
+
+#include "debug.h"
+
+static int native_interrupts_enabled;
+static int native_in_irs;
+
+static int last_sig;
+static ucontext_t native_context;
+static sigset_t native_sig_set;
+static char __isr_stack[SIGSTKSZ];
+extern volatile tcb_t *active_thread;
+
+struct int_handler_t {
+    void (*func)(void);
+};
+static struct int_handler_t native_irq_handlers[255];
+
+unsigned disableIRQ(void)
+{
+    unsigned int prev_state;
+    sigset_t mask;
+
+    DEBUG("disableIRQ()\n");
+
+    if (sigfillset(&mask) == -1) {
+        err(1, "disableIRQ(): sigfillset");
+    }
+    if (native_interrupts_enabled == 1) {
+        if (sigprocmask(SIG_SETMASK, &mask, &native_sig_set) == -1) {
+            err(1, "disableIRQ(): sigprocmask");
+        }
+    }
+    else {
+        if (sigprocmask(SIG_SETMASK, &mask, NULL) == -1) {
+            err(1, "disableIRQ(): sigprocmask()");
+        }
+    }
+    prev_state = native_interrupts_enabled;
+    native_interrupts_enabled = 0;
+
+    return prev_state;
+}
+
+unsigned enableIRQ(void)
+{
+    unsigned int prev_state;
+
+    DEBUG("enableIRQ()\n");
+
+    if (sigprocmask(SIG_SETMASK, &native_sig_set, NULL) == -1) {
+        err(1, "enableIRQ(): sigprocmask()");
+    }
+    prev_state = native_interrupts_enabled;
+    native_interrupts_enabled = 1;
+
+    return prev_state;
+}
+
+void restoreIRQ(unsigned state)
+{
+    DEBUG("restoreIRQ()\n");
+
+    if (state == 1) {
+        enableIRQ();
+    }
+    else {
+        disableIRQ();
+    }
+    return;
+}
+
+int inISR(void)
+{
+    DEBUG("inISR()\n");
+    return native_in_irs;
+}
+
+
+void dINT(void)
+{
+    disableIRQ();
+}
+
+void eINT(void)
+{
+    enableIRQ();
+}
+
+/**
+ * call signal handler,
+ * restore user context
+ */
+void native_irq_handler()
+{
+    if (native_irq_handlers[last_sig].func != NULL) {
+        DEBUG("calling interrupt handler for %i\n", last_sig);
+        native_irq_handlers[last_sig].func();
+    }
+    else {
+        printf("XXX: no handler for signal %i\n", last_sig);
+        errx(1, "XXX: this should not have happened!\n");
+    }
+    native_in_irs = 0;
+    cpu_switch_context_exit();
+}
+
+
+/**
+ * load isr context, save signal
+ */
+void native_isr_entry(int sig, siginfo_t *info, void *context)
+{
+    /* 
+     * This is how it goes:
+     * We create a new context "R" for the RIOT interrupt service
+     * routine.
+     * We save the current (signalhandler) context "S" to the active
+     * threads context. 
+     * We then jump into the R context.
+     * Later, when jumping back into "S", we start out in the signal
+     * handler context only to immediately return into the context we
+     * originally left. This step is done by the kernel for us.
+     *
+     * So the thing to wrap your head around is that the active thread
+     * remains within in the signal handler context (which is pushed
+     * onto the active threads own stack by swapcontext) until the
+     * thread is activated again, at which point the kernel handles
+     * the context switch back onto the interrupted context for us.
+     * */
+
+    /* save the signal */
+    last_sig = sig;
+    /* indicate irs status */
+    native_in_irs = 1;
+    
+    if (getcontext(&native_context) == -1) {
+        err(1, "native_isr_entry(): getcontext()");
+    }
+
+    native_context.uc_stack.ss_sp = __isr_stack;
+    native_context.uc_stack.ss_size = SIGSTKSZ;
+    native_context.uc_stack.ss_flags = 0;
+
+    /* XXX: disable interrupts
+     * -> sigfillset(&(native_context.uc_sigmask));
+     * else: */
+    //sigemptyset(&(native_context.uc_sigmask));
+    if (sigfillset(&(native_context.uc_sigmask)) == -1) {
+        err(1, "native_isr_entry(): sigfillset()");
+    }
+
+    makecontext(&native_context, native_irq_handler, 0);
+
+    if ((swapcontext((ucontext_t*)active_thread->sp, &native_context)) == -1) {
+        err(1, "swapcontext failed");
+    }
+    else {
+        DEBUG("returning to interrupted thread\n");
+    }
+    native_in_irs = 0;
+    enableIRQ();
+}
+
+/**
+ * TODO: check sa_flags for appropriateness
+ * TODO: use appropriate data structure (hashmap?) for signal
+ *       handlers.
+ */
+int register_interrupt(int sig, void *handler)
+{
+    struct sigaction sa;
+    DEBUG("XXX: register_interrupt()\n");
+
+    if (sigaddset(&native_sig_set, sig)) {
+        err(1, "register_interrupt: sigaddset");
+    }
+
+    native_irq_handlers[sig].func = handler;
+
+    sa.sa_sigaction = (void*) native_isr_entry;
+
+    if (sigemptyset(&sa.sa_mask) == -1) {
+        err(1, "register_interrupt: sigemptyset");
+    }
+
+    sa.sa_flags = SA_RESTART | SA_SIGINFO;
+
+    if (sigaction(sig, &sa, NULL)) {
+        err(1, "register_interrupt: sigaction");
+    }
+
+    return 0;
+}
+
+/**
+ * TODO: see register_interrupt
+ * TODO: ignore signal
+ */
+int unregister_interrupt(int sig)
+{
+    struct sigaction sa;
+    DEBUG("XXX: unregister_interrupt()\n");
+
+    if (sigdelset(&native_sig_set, sig) == -1) {
+        err(1, "unregister_interrupt: sigdelset");
+    }
+    native_irq_handlers[sig].func = NULL;
+
+    sa.sa_sigaction = SIG_IGN;
+    if (sigemptyset(&sa.sa_mask) == -1) {
+        err(1, "unregister_interrupt: sigemptyset");
+    }
+    sa.sa_flags = SA_RESTART | SA_SIGINFO;
+
+    if (sigaction(sig, &sa, NULL)) {
+        err(1, "register_interrupt: sigaction");
+    }
+    return 0;
+}
+
+
+/**
+ * TODO: see register_interrupt
+ */
+void native_interrupt_init(void)
+{
+    struct sigaction sa;
+    DEBUG("XXX: native_interrupt_init()\n");
+
+    for (int i = 0; i<255; i++) {
+        native_irq_handlers[i].func = NULL;
+    }
+
+    sa.sa_sigaction = (void*) native_isr_entry;
+    if (sigemptyset(&sa.sa_mask) == -1) {
+        err(1, "native_interrupt_init: sigemptyset");
+    }
+    sa.sa_flags = SA_RESTART | SA_SIGINFO;
+
+    if (sigemptyset(&native_sig_set) == -1) {
+        err(1, "native_interrupt_init: sigemptyset");
+    }
+    if (sigaddset(&native_sig_set, SIGUSR1) == -1) {
+        err(1, "native_interrupt_init: sigaddset");
+    }
+
+    if (sigaction(SIGUSR1, &sa, NULL)) {
+        err(1, "native_interrupt_init: sigaction");
+    }
+
+    puts("RIOT native interrupts/signals initialized.");
+}

cpu/native/lpm_cpu.c

@@ -0,0 +1,96 @@
+/**
+ * Native CPU lpm.h implementation
+ *
+ * Copyright (C) 2013 Ludwig Ortmann
+ *
+ * This file subject to the terms and conditions of the GNU General Public
+ * License. See the file LICENSE in the top level directory for more details.
+ *
+ * @ingroup arch
+ * @{
+ * @file
+ * @author  Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ * @}
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "lpm.h"
+#include "debug.h"
+
+static enum lpm_mode native_lpm;
+
+void lpm_init(void)
+{
+    DEBUG("lpm_init()\n");
+    native_lpm = LPM_ON;
+    return;
+}
+
+enum lpm_mode lpm_set(enum lpm_mode target)
+{
+    enum lpm_mode last_lpm;
+
+    DEBUG("lpm_set(%i)\n", target);
+
+    last_lpm = native_lpm;
+    native_lpm = target;
+
+    switch(native_lpm) /* @contiki :-p  */
+    {
+        case LPM_ON:
+            break;
+
+        case LPM_IDLE:
+            DEBUG("lpm_set(): pause()\n");
+            pause();
+            break;
+
+        /* XXX: unfinished modes: */
+        case LPM_SLEEP:
+            /*TODO: implement*/
+            printf("XXX: lpm_set(): LPM_SLEEP not implemented\n");
+            //sigsuspend();
+
+        case LPM_POWERDOWN:
+            /*TODO: implement*/
+            printf("XXX: lpm_set(): LPM_POWERDOWN not implemented\n");
+            //sigsuspend();
+
+        case LPM_OFF:
+            printf("lpm_set(): exit()\n");
+            exit(0);
+            break;
+
+        default:
+            DEBUG("XXX: unsupported power mode: %i\n", native_lpm);
+            exit(1);
+    }
+
+    return last_lpm;
+}
+
+void lpm_awake(void)
+{
+    DEBUG("XXX: lpm_awake()\n");
+    native_lpm = LPM_ON;
+    return;
+}
+
+void lpm_begin_awake(void)
+{
+    DEBUG("XXX: lpm_begin_awake()\n");
+    return;
+}
+
+void lpm_end_awake(void)
+{
+    DEBUG("XXX: lpm_end_awake()\n");
+    native_lpm = LPM_ON;
+    return;
+}
+enum lpm_mode lpm_get(void)
+{
+    return native_lpm;
+}

cpu/native/native_cpu.c

@@ -0,0 +1,111 @@
+/**
+ * Native CPU kernel_intern.h and sched.h implementation
+ *
+ * Copyright (C) 2013 Ludwig Ortmann
+ *
+ * This file subject to the terms and conditions of the GNU General Public
+ * License. See the file LICENSE in the top level directory for more details.
+ *
+ * @ingroup arch
+ * @{
+ * @file
+ * @author  Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ * @}
+ */
+#include <stdio.h>
+#include <ucontext.h>
+#include <err.h>
+
+#include "kernel_intern.h"
+#include "sched.h"
+
+#include "cpu.h"
+#include "cpu-conf.h"
+#include "debug.h"
+
+extern volatile tcb_t *active_thread;
+static ucontext_t native_context;
+static char __isr_stack[SIGSTKSZ];
+
+/**
+ * TODO: implement
+ */
+void thread_print_stack(void)
+{
+    DEBUG("XXX: thread_print_stack()\n");
+    return;
+}
+
+char *thread_stack_init(void *task_func, void *stack_start, int stacksize)
+{
+    unsigned int *stk;
+    ucontext_t *p;
+
+    DEBUG("thread_stack_init()\n");
+
+    stk = stack_start;
+
+#ifdef NATIVESPONTOP
+    p = (ucontext_t*)stk;
+    stk += sizeof(ucontext_t)/sizeof(void*);
+    stacksize -= sizeof(ucontext_t);
+#else
+    p = (ucontext_t*)(stk + ((stacksize-sizeof(ucontext_t))/sizeof(void*)));
+    stacksize -= sizeof(ucontext_t);
+#endif
+
+    if (getcontext(p) == -1) {
+        err(1, "thread_stack_init(): getcontext()");
+    }
+
+    p->uc_stack.ss_sp = stk;
+    p->uc_stack.ss_size = stacksize;
+    p->uc_stack.ss_flags = 0;
+    p->uc_link = &native_context;
+    if (sigemptyset(&(p->uc_sigmask)) == -1) {
+        err(1, "thread_stack_init(): sigemptyset()");
+    }
+
+    makecontext(p, task_func, 0);
+
+    return (char *) p;
+}
+
+void cpu_switch_context_exit(void)
+{
+    DEBUG("XXX: cpu_switch_context_exit()\n");
+    //active_thread = sched_threads[0];
+    sched_run();
+
+    DEBUG("XXX: cpu_switch_context_exit(): calling setcontext(%s)\n\n", active_thread->name);
+    if (setcontext((ucontext_t*)(active_thread->sp)) == -1) {
+        err(1, "cpu_switch_context_exit(): setcontext():");
+    }
+}
+
+void thread_yield()
+{
+    ucontext_t *oc;
+
+    DEBUG("thread_yield()\n");
+
+    oc = (ucontext_t*)(active_thread->sp);
+    sched_run();
+
+    DEBUG("thread_yield(): calling swapcontext(%s)\n\n", active_thread->name);
+    if (swapcontext(oc, (ucontext_t*)(active_thread->sp)) == -1) {
+        err(1, "thread_yield(): swapcontext()");
+    }
+}
+
+void native_cpu_init()
+{
+    if (getcontext(&native_context) == -1) {
+        err(1, "native_context(): getcontext()");
+    }
+    native_context.uc_stack.ss_sp = __isr_stack;
+    native_context.uc_stack.ss_size = SIGSTKSZ;
+    native_context.uc_stack.ss_flags = 0;
+    makecontext(&native_context, sched_task_exit, 0);
+    puts("RIOT native cpu initialized.");
+}

cpu/native/rtc/Makefile

@@ -0,0 +1,6 @@
+INCLUDES = -I$(RIOTBASE)/drivers/include -I$(RIOTBASE)/core/include
+
+MODULE =rtc
+
+include $(MAKEBASE)/Makefile.base
+

cpu/native/rtc/posix-rtc.c

@@ -0,0 +1,75 @@
+/**
+ * Native CPU rtc.h implementation
+ *
+ * Copyright (C) 2013 Ludwig Ortmann
+ *
+ * This file subject to the terms and conditions of the GNU General Public
+ * License. See the file LICENSE in the top level directory for more details.
+ *
+ * @ingroup arch
+ * @{
+ * @file
+ * @author  Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ * @}
+ */
+
+#include <time.h>
+#include <err.h>
+
+#include "debug.h"
+
+#include <rtc.h>
+
+static int native_rtc_enabled;
+
+/**
+ * @brief Initializes the RTC for calendar mode
+ */
+void rtc_init(void)
+{
+    native_rtc_enabled = 0;
+    printf("native rtc initialized\n");
+}
+
+/**
+ * @brief Starts the RTC
+ */
+void rtc_enable(void)
+{
+    DEBUG("rtc_enable\n");
+    native_rtc_enabled = 1;
+}
+
+/**
+ * @brief Stops the RTC
+ */
+void rtc_disable(void)
+{
+    DEBUG("rtc_disable()\n");
+    native_rtc_enabled = 0;
+}
+
+/**
+ * @brief	Sets the current time in broken down format directly from to RTC
+ * @param[in]	localt		Pointer to structure with time to set
+ */
+void rtc_set_localtime(struct tm* localt)
+{
+    DEBUG("rtc_set_localtime()\n");
+    printf("setting time not supported.");
+}
+
+/**
+ * @brief	Returns the current time in broken down format directly from the RTC
+ * @param[out]	localt		Pointer to structure to receive time
+ */
+void rtc_get_localtime(struct tm* localt)
+{
+    time_t t;
+    if(native_rtc_enabled == 1) {
+        t = time(NULL);
+        if (localtime_r(&t, localt) == NULL) {
+            err(1, "rtc_get_localtime: localtime_r");
+        }
+    }
+}

cpu/native/startup.c

@@ -0,0 +1,33 @@
+/**
+ * Native CPU entry code
+ *
+ * Copyright (C) 2013 Ludwig Ortmann
+ *
+ * This file subject to the terms and conditions of the GNU General Public
+ * License. See the file LICENSE in the top level directory for more details.
+ *
+ * @ingroup arch
+ * @{
+ * @file
+ * @author  Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ * @}
+ */
+
+#include <stdio.h>
+#include <kernel_intern.h>
+#include <cpu.h>
+
+extern void board_init(void);
+extern void native_cpu_init(void);
+extern void native_interrupt_init(void);
+
+__attribute__ ((constructor)) static void startup(void)
+{
+    native_cpu_init();
+    native_interrupt_init();
+
+    board_init();
+
+    puts("RIOT native hardware initialization complete.\n");
+    kernel_init();
+}