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		mov	ip, sp
22		stmfd	sp!, {r1 - r2, r4 - r8, fp, ip, lr, pc}
23		sub	fp, ip, #4
24		.endm
25
26		.macro	load_regs
27		ldmfd	sp, {r1, r2, r4-r8, fp, sp, pc}
28		.endm
29
30		.macro	load1b,	reg1
319999:		ldrbt	\reg1, [r0], $1
32		.section __ex_table, "a"
33		.align	3
34		.long	9999b, 6001f
35		.previous
36		.endm
37
38		.macro	load2b, reg1, reg2
399999:		ldrbt	\reg1, [r0], $1
409998:		ldrbt	\reg2, [r0], $1
41		.section __ex_table, "a"
42		.long	9999b, 6001f
43		.long	9998b, 6001f
44		.previous
45		.endm
46
47		.macro	load1l, reg1
489999:		ldrt	\reg1, [r0], $4
49		.section __ex_table, "a"
50		.align	3
51		.long	9999b, 6001f
52		.previous
53		.endm
54
55		.macro	load2l, reg1, reg2
569999:		ldrt	\reg1, [r0], $4
579998:		ldrt	\reg2, [r0], $4
58		.section __ex_table, "a"
59		.long	9999b, 6001f
60		.long	9998b, 6001f
61		.previous
62		.endm
63
64		.macro	load4l, reg1, reg2, reg3, reg4
659999:		ldrt	\reg1, [r0], $4
669998:		ldrt	\reg2, [r0], $4
679997:		ldrt	\reg3, [r0], $4
689996:		ldrt	\reg4, [r0], $4
69		.section __ex_table, "a"
70		.long	9999b, 6001f
71		.long	9998b, 6001f
72		.long	9997b, 6001f
73		.long	9996b, 6001f
74		.previous
75		.endm
76
77/*
78 * unsigned int
79 * csum_partial_copy_from_user(const char *src, char *dst, int len, int sum, int *err_ptr)
80 *  r0 = src, r1 = dst, r2 = len, r3 = sum, [sp] = *err_ptr
81 *  Returns : r0 = checksum, [[sp, #0], #0] = 0 or -EFAULT
82 */
83
84#define FN_ENTRY	ENTRY(csum_partial_copy_from_user)
85
86#include "csumpartialcopygeneric.S"
87
88/*
89 * FIXME: minor buglet here
90 * We don't return the checksum for the data present in the buffer.  To do
91 * so properly, we would have to add in whatever registers were loaded before
92 * the fault, which, with the current asm above is not predictable.
93 */
94		.section .fixup,"ax"
95		.align	4
966001:		mov	r4, #-EFAULT
97		ldr	r5, [fp, #4]		@ *err_ptr
98		str	r4, [r5]
99		ldmia	sp, {r1, r2}		@ retrieve dst, len
100		add	r2, r2, r1
101		mov	r0, #0			@ zero the buffer
1026002:		teq	r2, r1
103		strneb	r0, [r1], #1
104		bne	6002b
105		load_regs
106		.previous
107