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Diffstat (limited to 'arch/microblaze/lib/uaccess_old.S')
| -rw-r--r-- | arch/microblaze/lib/uaccess_old.S | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/arch/microblaze/lib/uaccess_old.S b/arch/microblaze/lib/uaccess_old.S new file mode 100644 index 000000000..dd5f3bfbc --- /dev/null +++ b/arch/microblaze/lib/uaccess_old.S @@ -0,0 +1,176 @@ +/* + * Copyright (C) 2009 Michal Simek <monstr@monstr.eu> + * Copyright (C) 2009 PetaLogix + * Copyright (C) 2007 LynuxWorks, Inc. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/errno.h> +#include <linux/linkage.h> +#include <asm/page.h> + +/* Loop unrolling for __copy_tofrom_user */ +#define COPY(offset) \ +1: lwi r4 , r6, 0x0000 + offset; \ +2: lwi r19, r6, 0x0004 + offset; \ +3: lwi r20, r6, 0x0008 + offset; \ +4: lwi r21, r6, 0x000C + offset; \ +5: lwi r22, r6, 0x0010 + offset; \ +6: lwi r23, r6, 0x0014 + offset; \ +7: lwi r24, r6, 0x0018 + offset; \ +8: lwi r25, r6, 0x001C + offset; \ +9: swi r4 , r5, 0x0000 + offset; \ +10: swi r19, r5, 0x0004 + offset; \ +11: swi r20, r5, 0x0008 + offset; \ +12: swi r21, r5, 0x000C + offset; \ +13: swi r22, r5, 0x0010 + offset; \ +14: swi r23, r5, 0x0014 + offset; \ +15: swi r24, r5, 0x0018 + offset; \ +16: swi r25, r5, 0x001C + offset; \ + .section __ex_table,"a"; \ + .word 1b, 33f; \ + .word 2b, 33f; \ + .word 3b, 33f; \ + .word 4b, 33f; \ + .word 5b, 33f; \ + .word 6b, 33f; \ + .word 7b, 33f; \ + .word 8b, 33f; \ + .word 9b, 33f; \ + .word 10b, 33f; \ + .word 11b, 33f; \ + .word 12b, 33f; \ + .word 13b, 33f; \ + .word 14b, 33f; \ + .word 15b, 33f; \ + .word 16b, 33f; \ + .text + +#define COPY_80(offset) \ + COPY(0x00 + offset);\ + COPY(0x20 + offset);\ + COPY(0x40 + offset);\ + COPY(0x60 + offset); + +/* + * int __copy_tofrom_user(char *to, char *from, int len) + * Return: + * 0 on success + * number of not copied bytes on error + */ + .text +.globl __copy_tofrom_user; +.type __copy_tofrom_user, @function +.align 4; +__copy_tofrom_user: + /* + * r5 - to + * r6 - from + * r7, r3 - count + * r4 - tempval + */ + beqid r7, 0f /* zero size is not likely */ + or r3, r5, r6 /* find if is any to/from unaligned */ + or r3, r3, r7 /* find if count is unaligned */ + andi r3, r3, 0x3 /* mask last 3 bits */ + bneid r3, bu1 /* if r3 is not zero then byte copying */ + or r3, r0, r0 + + rsubi r3, r7, PAGE_SIZE /* detect PAGE_SIZE */ + beqid r3, page; + or r3, r0, r0 + +w1: lw r4, r6, r3 /* at least one 4 byte copy */ +w2: sw r4, r5, r3 + addik r7, r7, -4 + bneid r7, w1 + addik r3, r3, 4 + addik r3, r7, 0 + rtsd r15, 8 + nop + + .section __ex_table,"a" + .word w1, 0f; + .word w2, 0f; + .text + +.align 4 /* Alignment is important to keep icache happy */ +page: /* Create room on stack and save registers for storing values */ + addik r1, r1, -40 + swi r5, r1, 0 + swi r6, r1, 4 + swi r7, r1, 8 + swi r19, r1, 12 + swi r20, r1, 16 + swi r21, r1, 20 + swi r22, r1, 24 + swi r23, r1, 28 + swi r24, r1, 32 + swi r25, r1, 36 +loop: /* r4, r19, r20, r21, r22, r23, r24, r25 are used for storing values */ + /* Loop unrolling to get performance boost */ + COPY_80(0x000); + COPY_80(0x080); + COPY_80(0x100); + COPY_80(0x180); + /* copy loop */ + addik r6, r6, 0x200 + addik r7, r7, -0x200 + bneid r7, loop + addik r5, r5, 0x200 + + /* Restore register content */ + lwi r5, r1, 0 + lwi r6, r1, 4 + lwi r7, r1, 8 + lwi r19, r1, 12 + lwi r20, r1, 16 + lwi r21, r1, 20 + lwi r22, r1, 24 + lwi r23, r1, 28 + lwi r24, r1, 32 + lwi r25, r1, 36 + addik r1, r1, 40 + /* return back */ + addik r3, r0, 0 + rtsd r15, 8 + nop + +/* Fault case - return temp count */ +33: + addik r3, r7, 0 + /* Restore register content */ + lwi r5, r1, 0 + lwi r6, r1, 4 + lwi r7, r1, 8 + lwi r19, r1, 12 + lwi r20, r1, 16 + lwi r21, r1, 20 + lwi r22, r1, 24 + lwi r23, r1, 28 + lwi r24, r1, 32 + lwi r25, r1, 36 + addik r1, r1, 40 + /* return back */ + rtsd r15, 8 + nop + +.align 4 /* Alignment is important to keep icache happy */ +bu1: lbu r4,r6,r3 +bu2: sb r4,r5,r3 + addik r7,r7,-1 + bneid r7,bu1 + addik r3,r3,1 /* delay slot */ +0: + addik r3,r7,0 + rtsd r15,8 + nop + .size __copy_tofrom_user, . - __copy_tofrom_user + + .section __ex_table,"a" + .word bu1, 0b; + .word bu2, 0b; + .text |