1 files changed, 105 insertions, 0 deletions
diff --git a/arch/mn10300/kernel/gdb-cache.S b/arch/mn10300/kernel/gdb-cache.S
new file mode 100644
index 00000000000..1108badc3d3
--- /dev/null
+++ b/arch/mn10300/kernel/gdb-cache.S
@@ -0,0 +1,105 @@
+###############################################################################
+#
+# MN10300 Low-level cache purging routines for gdbstub
+#
+# 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/smp.h>
+#include <asm/cache.h>
+#include <asm/cpu-regs.h>
+#include <asm/exceptions.h>
+#include <asm/frame.inc>
+#include <asm/serial-regs.h>
+
+	.text
+
+###############################################################################
+#
+# GDB stub cache purge
+#
+###############################################################################
+	.type	gdbstub_purge_cache,@function
+ENTRY(gdbstub_purge_cache)
+	#######################################################################
+	# read the addresses tagged in the cache's tag RAM and attempt to flush
+	# those addresses specifically
+	# - we rely on the hardware to filter out invalid tag entry addresses
+	mov	DCACHE_TAG(0,0),a0		# dcache tag RAM access address
+	mov	DCACHE_PURGE(0,0),a1		# dcache purge request address
+	mov	L1_CACHE_NWAYS*L1_CACHE_NENTRIES,d1  # total number of entries
+
+mn10300_dcache_flush_loop:
+	mov	(a0),d0
+	and	L1_CACHE_TAG_ADDRESS|L1_CACHE_TAG_ENTRY,d0
+	or	L1_CACHE_TAG_VALID,d0		# retain valid entries in the
+						# cache
+	mov	d0,(a1)				# conditional purge
+
+mn10300_dcache_flush_skip:
+	add	L1_CACHE_BYTES,a0
+	add	L1_CACHE_BYTES,a1
+	add	-1,d1
+	bne	mn10300_dcache_flush_loop
+
+;; 	# unconditionally flush and invalidate the dcache
+;; 	mov	DCACHE_PURGE(0,0),a1		# dcache purge request address
+;; 	mov	L1_CACHE_NWAYS*L1_CACHE_NENTRIES,d1	# total number of
+;;							# entries
+;;
+;; gdbstub_purge_cache__dcache_loop:
+;; 	mov	(a1),d0				# unconditional purge
+;;
+;; 	add	L1_CACHE_BYTES,a1
+;; 	add	-1,d1
+;; 	bne	gdbstub_purge_cache__dcache_loop
+
+	#######################################################################
+	# now invalidate the icache
+	mov	CHCTR,a0
+	movhu	(a0),a1
+
+	mov	epsw,d1
+	and	~EPSW_IE,epsw
+	nop
+	nop
+
+	# disable the icache
+	and	~CHCTR_ICEN,d0
+	movhu	d0,(a0)
+
+	# and wait for it to calm down
+	setlb
+	movhu	(a0),d0
+	btst	CHCTR_ICBUSY,d0
+	lne
+
+	# invalidate
+	or	CHCTR_ICINV,d0
+	movhu	d0,(a0)
+
+	# wait for the cache to finish
+	mov	CHCTR,a0
+	setlb
+	movhu	(a0),d0
+	btst	CHCTR_ICBUSY,d0
+	lne
+
+	# and reenable it
+	movhu	a1,(a0)
+	movhu	(a0),d0			# read back to flush
+					# (SIGILLs all over without this)
+
+	mov	d1,epsw
+
+	ret	[],0
+
+	.size	gdbstub_purge_cache,.-gdbstub_purge_cache