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authorDavid Howells <dhowells@redhat.com>2008-02-08 04:19:31 -0800
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2008-02-08 09:22:30 -0800
commitb920de1b77b72ca9432ac3f97edb26541e65e5dd (patch)
tree40fa9be1470e929c47927dea7eddf184c0204229 /arch/mn10300/lib/memcpy.S
parentef3d534754f31fed9c3b976fee1ece1b3bc38282 (diff)
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>
Diffstat (limited to 'arch/mn10300/lib/memcpy.S')
-rw-r--r--arch/mn10300/lib/memcpy.S135
1 files changed, 135 insertions, 0 deletions
diff --git a/arch/mn10300/lib/memcpy.S b/arch/mn10300/lib/memcpy.S
new file mode 100644
index 000000000000..25fb9bb2604f
--- /dev/null
+++ b/arch/mn10300/lib/memcpy.S
@@ -0,0 +1,135 @@
+/* MN10300 Optimised simple memory to memory copy
+ *
+ * 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 <asm/cache.h>
+
+ .section .text
+ .balign L1_CACHE_BYTES
+
+###############################################################################
+#
+# void *memcpy(void *dst, const void *src, size_t n)
+#
+###############################################################################
+ .globl memcpy
+ .type memcpy,@function
+memcpy:
+ movm [d2,d3],(sp)
+ mov d0,(12,sp)
+ mov d1,(16,sp)
+ mov (20,sp),d2 # count
+ mov d0,a0 # dst
+ mov d1,a1 # src
+ mov d0,e3 # the return value
+
+ cmp +0,d2
+ beq memcpy_done # return if zero-length copy
+
+ # see if the three parameters are all four-byte aligned
+ or d0,d1,d3
+ or d2,d3
+ and +3,d3
+ bne memcpy_1 # jump if not
+
+ # we want to transfer as much as we can in chunks of 32 bytes
+ cmp +31,d2
+ bls memcpy_4_remainder # 4-byte aligned remainder
+
+ movm [exreg1],(sp)
+ add -32,d2
+ mov +32,d3
+
+memcpy_4_loop:
+ mov (a1+),d0
+ mov (a1+),d1
+ mov (a1+),e0
+ mov (a1+),e1
+ mov (a1+),e4
+ mov (a1+),e5
+ mov (a1+),e6
+ mov (a1+),e7
+ mov d0,(a0+)
+ mov d1,(a0+)
+ mov e0,(a0+)
+ mov e1,(a0+)
+ mov e4,(a0+)
+ mov e5,(a0+)
+ mov e6,(a0+)
+ mov e7,(a0+)
+
+ sub d3,d2
+ bcc memcpy_4_loop
+
+ movm (sp),[exreg1]
+ add d3,d2
+ beq memcpy_4_no_remainder
+
+memcpy_4_remainder:
+ # cut 4-7 words down to 0-3
+ cmp +16,d2
+ bcs memcpy_4_three_or_fewer_words
+ mov (a1+),d0
+ mov (a1+),d1
+ mov (a1+),e0
+ mov (a1+),e1
+ mov d0,(a0+)
+ mov d1,(a0+)
+ mov e0,(a0+)
+ mov e1,(a0+)
+ add -16,d2
+ beq memcpy_4_no_remainder
+
+ # copy the remaining 1, 2 or 3 words
+memcpy_4_three_or_fewer_words:
+ cmp +8,d2
+ bcs memcpy_4_one_word
+ beq memcpy_4_two_words
+ mov (a1+),d0
+ mov d0,(a0+)
+memcpy_4_two_words:
+ mov (a1+),d0
+ mov d0,(a0+)
+memcpy_4_one_word:
+ mov (a1+),d0
+ mov d0,(a0+)
+
+memcpy_4_no_remainder:
+ # check we copied the correct amount
+ # TODO: REMOVE CHECK
+ sub e3,a0,d2
+ mov (20,sp),d1
+ cmp d2,d1
+ beq memcpy_done
+ break
+ break
+ break
+
+memcpy_done:
+ mov e3,a0
+ ret [d2,d3],8
+
+ # handle misaligned copying
+memcpy_1:
+ add -1,d2
+ mov +1,d3
+ setlb # setlb requires the next insns
+ # to occupy exactly 4 bytes
+
+ sub d3,d2
+ movbu (a1),d0
+ movbu d0,(a0)
+ add_add d3,a1,d3,a0
+ lcc
+
+ mov e3,a0
+ ret [d2,d3],8
+
+memcpy_end:
+ .size memcpy, memcpy_end-memcpy