| Haavard Skinnemoen | 5f97f7f | 2006-09-25 23:32:13 -0700 | [diff] [blame] | 1 | /* | 
|  | 2 | * Copyright 2004-2006 Atmel Corporation | 
|  | 3 | * | 
|  | 4 | * This program is free software; you can redistribute it and/or modify | 
|  | 5 | * it under the terms of the GNU General Public License version 2 as | 
|  | 6 | * published by the Free Software Foundation. | 
|  | 7 | */ | 
|  | 8 | #include <asm/page.h> | 
|  | 9 | #include <asm/thread_info.h> | 
|  | 10 | #include <asm/asm.h> | 
|  | 11 |  | 
|  | 12 | .text | 
|  | 13 | .align	1 | 
|  | 14 | .global	clear_user | 
|  | 15 | .type	clear_user, "function" | 
|  | 16 | clear_user: | 
|  | 17 | branch_if_kernel r8, __clear_user | 
|  | 18 | ret_if_privileged r8, r12, r11, r11 | 
|  | 19 |  | 
|  | 20 | .global	__clear_user | 
|  | 21 | .type	__clear_user, "function" | 
|  | 22 | __clear_user: | 
|  | 23 | mov	r9, r12 | 
|  | 24 | mov	r8, 0 | 
|  | 25 | andl	r9, 3, COH | 
|  | 26 | brne	5f | 
|  | 27 |  | 
|  | 28 | 1:	sub	r11, 4 | 
|  | 29 | brlt	2f | 
|  | 30 |  | 
|  | 31 | 10:	st.w	r12++, r8 | 
|  | 32 | sub	r11, 4 | 
|  | 33 | brge	10b | 
|  | 34 |  | 
|  | 35 | 2:	sub	r11, -4 | 
|  | 36 | reteq	0 | 
|  | 37 |  | 
|  | 38 | /* Unaligned count or address */ | 
|  | 39 | bld	r11, 1 | 
|  | 40 | brcc	12f | 
|  | 41 | 11:	st.h	r12++, r8 | 
|  | 42 | sub	r11, 2 | 
|  | 43 | reteq	0 | 
|  | 44 | 12:	st.b	r12++, r8 | 
|  | 45 | retal	0 | 
|  | 46 |  | 
|  | 47 | /* Unaligned address */ | 
|  | 48 | 5:	cp.w	r11, 4 | 
|  | 49 | brlt	2b | 
|  | 50 |  | 
|  | 51 | lsl	r9, 2 | 
|  | 52 | add	pc, pc, r9 | 
|  | 53 | 13:	st.b	r12++, r8 | 
|  | 54 | sub	r11, 1 | 
|  | 55 | 14:	st.b	r12++, r8 | 
|  | 56 | sub	r11, 1 | 
|  | 57 | 15:	st.b	r12++, r8 | 
|  | 58 | sub	r11, 1 | 
|  | 59 | rjmp	1b | 
|  | 60 |  | 
|  | 61 | .size	clear_user, . - clear_user | 
|  | 62 | .size	__clear_user, . - __clear_user | 
|  | 63 |  | 
|  | 64 | .section .fixup, "ax" | 
|  | 65 | .align	1 | 
|  | 66 | 18:	sub	r11, -4 | 
|  | 67 | 19:	retal	r11 | 
|  | 68 |  | 
|  | 69 | .section __ex_table, "a" | 
|  | 70 | .align	2 | 
|  | 71 | .long	10b, 18b | 
|  | 72 | .long	11b, 19b | 
|  | 73 | .long	12b, 19b | 
|  | 74 | .long	13b, 19b | 
|  | 75 | .long	14b, 19b | 
|  | 76 | .long	15b, 19b |