mn10300: add the MN10300/AM33 architecture to the kernel
Add architecture support for the MN10300/AM33 CPUs produced by MEI to the
kernel.
This patch also adds board support for the ASB2303 with the ASB2308 daughter
board, and the ASB2305. The only processor supported is the MN103E010, which
is an AM33v2 core plus on-chip devices.
[akpm@linux-foundation.org: nuke cvs control strings]
Signed-off-by: Masakazu Urade <urade.masakazu@jp.panasonic.com>
Signed-off-by: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/mn10300/kernel/switch_to.S b/arch/mn10300/kernel/switch_to.S
new file mode 100644
index 0000000..630aad7
--- /dev/null
+++ b/arch/mn10300/kernel/switch_to.S
@@ -0,0 +1,71 @@
+###############################################################################
+#
+# MN10300 Context switch operation
+#
+# Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+# Written by David Howells (dhowells@redhat.com)
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public Licence
+# as published by the Free Software Foundation; either version
+# 2 of the Licence, or (at your option) any later version.
+#
+###############################################################################
+#include <linux/sys.h>
+#include <linux/linkage.h>
+#include <asm/thread_info.h>
+#include <asm/cpu-regs.h>
+
+ .text
+
+###############################################################################
+#
+# struct task_struct *__switch_to(struct thread_struct *prev,
+# struct thread_struct *next,
+# struct task_struct *prev_task)
+#
+###############################################################################
+ENTRY(__switch_to)
+ movm [d2,d3,a2,a3,exreg1],(sp)
+ or EPSW_NMID,epsw
+
+ mov (44,sp),d2
+
+ mov d0,a0
+ mov d1,a1
+
+ # save prev context
+ mov (__frame),d0
+ mov d0,(THREAD_FRAME,a0)
+ mov __switch_back,d0
+ mov d0,(THREAD_PC,a0)
+ mov sp,a2
+ mov a2,(THREAD_SP,a0)
+ mov a3,(THREAD_A3,a0)
+
+ mov (THREAD_A3,a1),a3
+ mov (THREAD_SP,a1),a2
+
+ # switch
+ mov a2,sp
+
+ # load next context
+ GET_THREAD_INFO a2
+ mov a2,(__current_ti)
+ mov (TI_task,a2),a2
+ mov a2,(__current)
+#ifdef CONFIG_MN10300_CURRENT_IN_E2
+ mov a2,e2
+#endif
+
+ mov (THREAD_FRAME,a1),a2
+ mov a2,(__frame)
+ mov (THREAD_PC,a1),a2
+ mov d2,d0 # for ret_from_fork
+ mov d0,a0 # for __switch_to
+
+ jmp (a2)
+
+__switch_back:
+ and ~EPSW_NMID,epsw
+ ret [d2,d3,a2,a3,exreg1],32