prepare for switching threads

1 files changed, 52 insertions, 0 deletions

diff --git a/lib/libpthread/arch/m68k/uthread_machdep.c b/lib/libpthread/arch/m68k/uthread_machdep.c
new file mode 100644
index 00000000000..8afde2443f3
--- /dev/null
+++ b/lib/libpthread/arch/m68k/uthread_machdep.c
@@ -0,0 +1,52 @@
+/*	$OpenBSD: uthread_machdep.c,v 1.1 2000/09/25 09:03:44 d Exp $	*/
+/* David Leonard, <d@csee.uq.edu.au>. Public domain. */
+
+/*
+ * Machine-dependent thread state functions for OpenBSD/m68k
+ */
+
+#include "uthread_machdep.h"
+#define ALIGNBYTES	0x3
+
+struct frame {
+	int	d2,d3,d4,d5,d6,d7;
+	int	a2,a3,a4,a5,fp;
+	int	link;			/* frame link */
+	int	ra;
+};
+
+/*
+ * Given a stack and an entry function, initialise a state
+ * structure that can be later switched to.
+ */
+void
+_thread_machdep_init(statep, base, len, entry)
+	struct _machdep_state* statep;
+	void *base;
+	int len;
+	void (*entry)(void);
+{
+	struct frame *f;
+
+	/* Locate the initial frame, aligned at the top of the stack */
+	f = (struct frame *)(((int)base + len - sizeof *f) & ~ALIGNBYTES);
+	
+	f->ra = (int)entry;
+	f->link = 0;
+	f->fp = (int)&f->link;
+	statep->sp = (int)f;
+}
+
+void
+_thread_machdep_save_float_state(statep)
+	struct _machdep_state* statep;
+{
+	/* fsave is a privileged instruction */
+}
+
+void
+_thread_machdep_restore_float_state(statep)
+	struct _machdep_state* statep;
+{
+	/* frestore is a privileged instruction */
+}