1 files changed, 77 insertions, 0 deletions
diff --git a/arch/frv/kernel/kernel_thread.S b/arch/frv/kernel/kernel_thread.S
new file mode 100644
index 0000000..4531c83
--- /dev/null
+++ b/arch/frv/kernel/kernel_thread.S
@@ -0,0 +1,77 @@
+/* kernel_thread.S: kernel thread creation
+ *
+ * Copyright (C) 2003 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 License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/linkage.h>
+#include <asm/unistd.h>
+
+#define CLONE_VM	0x00000100	/* set if VM shared between processes */
+#define	KERN_ERR	"<3>"
+
+	.section .rodata
+kernel_thread_emsg:
+	.asciz	KERN_ERR "failed to create kernel thread: error=%d\n"
+
+	.text
+	.balign		4
+
+###############################################################################
+#
+# Create a kernel thread
+#
+# int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
+#
+###############################################################################
+	.globl		kernel_thread
+	.type		kernel_thread,@function
+kernel_thread:
+	or.p		gr8,gr0,gr4
+	or		gr9,gr0,gr5
+
+	# start by forking the current process, but with shared VM
+	setlos.p	#__NR_clone,gr7		; syscall number
+	ori		gr10,#CLONE_VM,gr8	; first syscall arg	[clone_flags]
+	sethi.p		#0xe4e4,gr9		; second syscall arg	[newsp]
+	setlo		#0xe4e4,gr9
+	setlos.p	#0,gr10			; third syscall arg	[parent_tidptr]
+	setlos		#0,gr11			; fourth syscall arg	[child_tidptr]
+	tira		gr0,#0
+	setlos.p	#4095,gr7
+	andcc		gr8,gr8,gr0,icc0
+	addcc.p		gr8,gr7,gr0,icc1
+	bnelr		icc0,#2
+	bc		icc1,#0,kernel_thread_error
+
+	# now invoke the work function
+	or		gr5,gr0,gr8
+	calll		@(gr4,gr0)
+
+	# and finally exit the thread
+	setlos		#__NR_exit,gr7		; syscall number
+	tira		gr0,#0
+
+kernel_thread_error:
+	subi		sp,#8,sp
+	movsg		lr,gr4
+	sti		gr8,@(sp,#0)
+	sti.p		gr4,@(sp,#4)
+
+	or		gr8,gr0,gr9
+	sethi.p		%hi(kernel_thread_emsg),gr8
+	setlo		%lo(kernel_thread_emsg),gr8
+
+	call		printk
+
+	ldi		@(sp,#4),gr4
+	ldi		@(sp,#0),gr8
+	subi		sp,#8,sp
+	jmpl		@(gr4,gr0)
+
+	.size		kernel_thread,.-kernel_thread