1/*
2 *  linux/arch/arm/lib/csumpartialcopyuser.S
3 *
4 *  Copyright (C) 1995-1998 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * 27/03/03 Ian Molton Clean up CONFIG_CPU
11 *
12 */
13#include <linux/linkage.h>
14#include <asm/assembler.h>
15#include <asm/errno.h>
16#include <asm/asm-offsets.h>
17
18		.text
19
20		.macro	save_regs
21		stmfd	sp!, {r1, r2, r4 - r8, lr}
22		.endm
23
24		.macro	load_regs
25		ldmfd	sp!, {r1, r2, r4 - r8, pc}
26		.endm
27
28		.macro	load1b,	reg1
29		ldrusr	\reg1, r0, 1
30		.endm
31
32		.macro	load2b, reg1, reg2
33		ldrusr	\reg1, r0, 1
34		ldrusr	\reg2, r0, 1
35		.endm
36
37		.macro	load1l, reg1
38		ldrusr	\reg1, r0, 4
39		.endm
40
41		.macro	load2l, reg1, reg2
42		ldrusr	\reg1, r0, 4
43		ldrusr	\reg2, r0, 4
44		.endm
45
46		.macro	load4l, reg1, reg2, reg3, reg4
47		ldrusr	\reg1, r0, 4
48		ldrusr	\reg2, r0, 4
49		ldrusr	\reg3, r0, 4
50		ldrusr	\reg4, r0, 4
51		.endm
52
53/*
54 * unsigned int
55 * csum_partial_copy_from_user(const char *src, char *dst, int len, int sum, int *err_ptr)
56 *  r0 = src, r1 = dst, r2 = len, r3 = sum, [sp] = *err_ptr
57 *  Returns : r0 = checksum, [[sp, #0], #0] = 0 or -EFAULT
58 */
59
60#define FN_ENTRY	ENTRY(csum_partial_copy_from_user)
61#define FN_EXIT		ENDPROC(csum_partial_copy_from_user)
62
63#include "csumpartialcopygeneric.S"
64
65/*
66 * FIXME: minor buglet here
67 * We don't return the checksum for the data present in the buffer.  To do
68 * so properly, we would have to add in whatever registers were loaded before
69 * the fault, which, with the current asm above is not predictable.
70 */
71		.pushsection .text.fixup,"ax"
72		.align	4
739001:		mov	r4, #-EFAULT
74		ldr	r5, [sp, #8*4]		@ *err_ptr
75		str	r4, [r5]
76		ldmia	sp, {r1, r2}		@ retrieve dst, len
77		add	r2, r2, r1
78		mov	r0, #0			@ zero the buffer
799002:		teq	r2, r1
80		strneb	r0, [r1], #1
81		bne	9002b
82		load_regs
83		.popsection
84