Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*
 *  linux/arch/arm/lib/uaccess.S
 *
 *  Copyright (C) 1995, 1996,1997,1998 Russell King
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 *  Routines to block copy data to/from user memory
 *   These are highly optimised both for the 4k page size
 *   and for various alignments.
 */
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/errno.h>

                .text

#define PAGE_SHIFT 12

/* Prototype: int __copy_to_user(void *to, const char *from, size_t n)
 * Purpose  : copy a block to user memory from kernel memory
 * Params   : to   - user memory
 *          : from - kernel memory
 *          : n    - number of bytes to copy
 * Returns  : Number of bytes NOT copied.
 */

.Lc2u_dest_not_aligned:
                rsb     ip, ip, #4
                cmp     ip, #2
                ldrb    r3, [r1], #1
USER(           strbt   r3, [r0], #1)                   @ May fault
                ldrgeb  r3, [r1], #1
USER(           strgebt r3, [r0], #1)                   @ May fault
                ldrgtb  r3, [r1], #1
USER(           strgtbt r3, [r0], #1)                   @ May fault
                sub     r2, r2, ip
                b       .Lc2u_dest_aligned

ENTRY(__copy_to_user)
                stmfd   sp!, {r2, r4 - r7, lr}
                cmp     r2, #4
                blt     .Lc2u_not_enough
                ands    ip, r0, #3
                bne     .Lc2u_dest_not_aligned
.Lc2u_dest_aligned:

                ands    ip, r1, #3
                bne     .Lc2u_src_not_aligned
/*
 * Seeing as there has to be at least 8 bytes to copy, we can
 * copy one word, and force a user-mode page fault...
 */

.Lc2u_0fupi:    subs    r2, r2, #4
                addmi   ip, r2, #4
                bmi     .Lc2u_0nowords
                ldr     r3, [r1], #4
USER(           strt    r3, [r0], #4)                   @ May fault
                mov     ip, r0, lsl #32 - PAGE_SHIFT    @ On each page, use a ld/st??t instruction
                rsb     ip, ip, #0
                movs    ip, ip, lsr #32 - PAGE_SHIFT
                beq     .Lc2u_0fupi
/*
 * ip = max no. of bytes to copy before needing another "strt" insn
 */
                cmp     r2, ip
                movlt   ip, r2
                sub     r2, r2, ip
                subs    ip, ip, #32
                blt     .Lc2u_0rem8lp

.Lc2u_0cpy8lp:  ldmia   r1!, {r3 - r6}
                stmia   r0!, {r3 - r6}                  @ Shouldnt fault
                ldmia   r1!, {r3 - r6}
                subs    ip, ip, #32
                stmia   r0!, {r3 - r6}                  @ Shouldnt fault
                bpl     .Lc2u_0cpy8lp

.Lc2u_0rem8lp:  cmn     ip, #16
                ldmgeia r1!, {r3 - r6}
                stmgeia r0!, {r3 - r6}                  @ Shouldnt fault
                tst     ip, #8
                ldmneia r1!, {r3 - r4}
                stmneia r0!, {r3 - r4}                  @ Shouldnt fault
                tst     ip, #4
                ldrne   r3, [r1], #4
                strnet  r3, [r0], #4                    @ Shouldnt fault
                ands    ip, ip, #3
                beq     .Lc2u_0fupi
.Lc2u_0nowords: teq     ip, #0
                beq     .Lc2u_finished
.Lc2u_nowords:  cmp     ip, #2
                ldrb    r3, [r1], #1
USER(           strbt   r3, [r0], #1)                   @ May fault
                ldrgeb  r3, [r1], #1
USER(           strgebt r3, [r0], #1)                   @ May fault
                ldrgtb  r3, [r1], #1
USER(           strgtbt r3, [r0], #1)                   @ May fault
                b       .Lc2u_finished

.Lc2u_not_enough:
                movs    ip, r2
                bne     .Lc2u_nowords
.Lc2u_finished: mov     r0, #0
                ldmfd   sp!, {r2, r4 - r7, pc}

.Lc2u_src_not_aligned:
                bic     r1, r1, #3
                ldr     r7, [r1], #4
                cmp     ip, #2
                bgt     .Lc2u_3fupi
                beq     .Lc2u_2fupi
.Lc2u_1fupi:    subs    r2, r2, #4
                addmi   ip, r2, #4
                bmi     .Lc2u_1nowords
                mov     r3, r7, pull #8
                ldr     r7, [r1], #4
                orr     r3, r3, r7, push #24
USER(           strt    r3, [r0], #4)                   @ May fault
                mov     ip, r0, lsl #32 - PAGE_SHIFT
                rsb     ip, ip, #0
                movs    ip, ip, lsr #32 - PAGE_SHIFT
                beq     .Lc2u_1fupi
                cmp     r2, ip
                movlt   ip, r2
                sub     r2, r2, ip
                subs    ip, ip, #16
                blt     .Lc2u_1rem8lp

.Lc2u_1cpy8lp:  mov     r3, r7, pull #8
                ldmia   r1!, {r4 - r7}
                subs    ip, ip, #16
                orr     r3, r3, r4, push #24
                mov     r4, r4, pull #8
                orr     r4, r4, r5, push #24
                mov     r5, r5, pull #8
                orr     r5, r5, r6, push #24
                mov     r6, r6, pull #8
                orr     r6, r6, r7, push #24
                stmia   r0!, {r3 - r6}                  @ Shouldnt fault
                bpl     .Lc2u_1cpy8lp

.Lc2u_1rem8lp:  tst     ip, #8
                movne   r3, r7, pull #8
                ldmneia r1!, {r4, r7}
                orrne   r3, r3, r4, push #24
                movne   r4, r4, pull #8
                orrne   r4, r4, r7, push #24
                stmneia r0!, {r3 - r4}                  @ Shouldnt fault
                tst     ip, #4
                movne   r3, r7, pull #8
                ldrne   r7, [r1], #4
                orrne   r3, r3, r7, push #24
                strnet  r3, [r0], #4                    @ Shouldnt fault
                ands    ip, ip, #3
                beq     .Lc2u_1fupi
.Lc2u_1nowords: mov     r3, r7, get_byte_1
                teq     ip, #0
                beq     .Lc2u_finished
                cmp     ip, #2
USER(           strbt   r3, [r0], #1)                   @ May fault
                movge   r3, r7, get_byte_2
USER(           strgebt r3, [r0], #1)                   @ May fault
                movgt   r3, r7, get_byte_3
USER(           strgtbt r3, [r0], #1)                   @ May fault
                b       .Lc2u_finished

.Lc2u_2fupi:    subs    r2, r2, #4
                addmi   ip, r2, #4
                bmi     .Lc2u_2nowords
                mov     r3, r7, pull #16
                ldr     r7, [r1], #4
                orr     r3, r3, r7, push #16
USER(           strt    r3, [r0], #4)                   @ May fault
                mov     ip, r0, lsl #32 - PAGE_SHIFT
                rsb     ip, ip, #0
                movs    ip, ip, lsr #32 - PAGE_SHIFT
                beq     .Lc2u_2fupi
                cmp     r2, ip
                movlt   ip, r2
                sub     r2, r2, ip
                subs    ip, ip, #16
                blt     .Lc2u_2rem8lp

.Lc2u_2cpy8lp:  mov     r3, r7, pull #16
                ldmia   r1!, {r4 - r7}
                subs    ip, ip, #16
                orr     r3, r3, r4, push #16
                mov     r4, r4, pull #16
                orr     r4, r4, r5, push #16
                mov     r5, r5, pull #16
                orr     r5, r5, r6, push #16
                mov     r6, r6, pull #16
                orr     r6, r6, r7, push #16
                stmia   r0!, {r3 - r6}                  @ Shouldnt fault
                bpl     .Lc2u_2cpy8lp

.Lc2u_2rem8lp:  tst     ip, #8
                movne   r3, r7, pull #16
                ldmneia r1!, {r4, r7}
                orrne   r3, r3, r4, push #16
                movne   r4, r4, pull #16
                orrne   r4, r4, r7, push #16
                stmneia r0!, {r3 - r4}                  @ Shouldnt fault
                tst     ip, #4
                movne   r3, r7, pull #16
                ldrne   r7, [r1], #4
                orrne   r3, r3, r7, push #16
                strnet  r3, [r0], #4                    @ Shouldnt fault
                ands    ip, ip, #3
                beq     .Lc2u_2fupi
.Lc2u_2nowords: mov     r3, r7, get_byte_2
                teq     ip, #0
                beq     .Lc2u_finished
                cmp     ip, #2
USER(           strbt   r3, [r0], #1)                   @ May fault
                movge   r3, r7, get_byte_3
USER(           strgebt r3, [r0], #1)                   @ May fault
                ldrgtb  r3, [r1], #0
USER(           strgtbt r3, [r0], #1)                   @ May fault
                b       .Lc2u_finished

.Lc2u_3fupi:    subs    r2, r2, #4
                addmi   ip, r2, #4
                bmi     .Lc2u_3nowords
                mov     r3, r7, pull #24
                ldr     r7, [r1], #4
                orr     r3, r3, r7, push #8
USER(           strt    r3, [r0], #4)                   @ May fault
                mov     ip, r0, lsl #32 - PAGE_SHIFT
                rsb     ip, ip, #0
                movs    ip, ip, lsr #32 - PAGE_SHIFT
                beq     .Lc2u_3fupi
                cmp     r2, ip
                movlt   ip, r2
                sub     r2, r2, ip
                subs    ip, ip, #16
                blt     .Lc2u_3rem8lp

.Lc2u_3cpy8lp:  mov     r3, r7, pull #24
                ldmia   r1!, {r4 - r7}
                subs    ip, ip, #16
                orr     r3, r3, r4, push #8
                mov     r4, r4, pull #24
                orr     r4, r4, r5, push #8
                mov     r5, r5, pull #24
                orr     r5, r5, r6, push #8
                mov     r6, r6, pull #24
                orr     r6, r6, r7, push #8
                stmia   r0!, {r3 - r6}                  @ Shouldnt fault
                bpl     .Lc2u_3cpy8lp

.Lc2u_3rem8lp:  tst     ip, #8
                movne   r3, r7, pull #24
                ldmneia r1!, {r4, r7}
                orrne   r3, r3, r4, push #8
                movne   r4, r4, pull #24
                orrne   r4, r4, r7, push #8
                stmneia r0!, {r3 - r4}                  @ Shouldnt fault
                tst     ip, #4
                movne   r3, r7, pull #24
                ldrne   r7, [r1], #4
                orrne   r3, r3, r7, push #8
                strnet  r3, [r0], #4                    @ Shouldnt fault
                ands    ip, ip, #3
                beq     .Lc2u_3fupi
.Lc2u_3nowords: mov     r3, r7, get_byte_3
                teq     ip, #0
                beq     .Lc2u_finished
                cmp     ip, #2
USER(           strbt   r3, [r0], #1)                   @ May fault
                ldrgeb  r3, [r1], #1
USER(           strgebt r3, [r0], #1)                   @ May fault
                ldrgtb  r3, [r1], #0
USER(           strgtbt r3, [r0], #1)                   @ May fault
                b       .Lc2u_finished

                .section .fixup,"ax"
                .align  0
9001:           ldmfd   sp!, {r0, r4 - r7, pc}
                .previous

/* Prototype: unsigned long __copy_from_user(void *to,const void *from,unsigned long n);
 * Purpose  : copy a block from user memory to kernel memory
 * Params   : to   - kernel memory
 *          : from - user memory
 *          : n    - number of bytes to copy
 * Returns  : Number of bytes NOT copied.
 */
.Lcfu_dest_not_aligned:
                rsb     ip, ip, #4
                cmp     ip, #2
USER(           ldrbt   r3, [r1], #1)                   @ May fault
                strb    r3, [r0], #1
USER(           ldrgebt r3, [r1], #1)                   @ May fault
                strgeb  r3, [r0], #1
USER(           ldrgtbt r3, [r1], #1)                   @ May fault
                strgtb  r3, [r0], #1
                sub     r2, r2, ip
                b       .Lcfu_dest_aligned

ENTRY(__copy_from_user)
                stmfd   sp!, {r0, r2, r4 - r7, lr}
                cmp     r2, #4
                blt     .Lcfu_not_enough
                ands    ip, r0, #3
                bne     .Lcfu_dest_not_aligned
.Lcfu_dest_aligned:
                ands    ip, r1, #3
                bne     .Lcfu_src_not_aligned

/*
 * Seeing as there has to be at least 8 bytes to copy, we can
 * copy one word, and force a user-mode page fault...
 */

.Lcfu_0fupi:    subs    r2, r2, #4
                addmi   ip, r2, #4
                bmi     .Lcfu_0nowords
USER(           ldrt    r3, [r1], #4)
                str     r3, [r0], #4
                mov     ip, r1, lsl #32 - PAGE_SHIFT    @ On each page, use a ld/st??t instruction
                rsb     ip, ip, #0
                movs    ip, ip, lsr #32 - PAGE_SHIFT
                beq     .Lcfu_0fupi
/*
 * ip = max no. of bytes to copy before needing another "strt" insn
 */
                cmp     r2, ip
                movlt   ip, r2
                sub     r2, r2, ip
                subs    ip, ip, #32
                blt     .Lcfu_0rem8lp

.Lcfu_0cpy8lp:  ldmia   r1!, {r3 - r6}                  @ Shouldnt fault
                stmia   r0!, {r3 - r6}
                ldmia   r1!, {r3 - r6}                  @ Shouldnt fault
                subs    ip, ip, #32
                stmia   r0!, {r3 - r6}
                bpl     .Lcfu_0cpy8lp

.Lcfu_0rem8lp:  cmn     ip, #16
                ldmgeia r1!, {r3 - r6}                  @ Shouldnt fault
                stmgeia r0!, {r3 - r6}
                tst     ip, #8
                ldmneia r1!, {r3 - r4}                  @ Shouldnt fault
                stmneia r0!, {r3 - r4}
                tst     ip, #4
                ldrnet  r3, [r1], #4                    @ Shouldnt fault
                strne   r3, [r0], #4
                ands    ip, ip, #3
                beq     .Lcfu_0fupi
.Lcfu_0nowords: teq     ip, #0
                beq     .Lcfu_finished
.Lcfu_nowords:  cmp     ip, #2
USER(           ldrbt   r3, [r1], #1)                   @ May fault
                strb    r3, [r0], #1
USER(           ldrgebt r3, [r1], #1)                   @ May fault
                strgeb  r3, [r0], #1
USER(           ldrgtbt r3, [r1], #1)                   @ May fault
                strgtb  r3, [r0], #1
                b       .Lcfu_finished

.Lcfu_not_enough:
                movs    ip, r2
                bne     .Lcfu_nowords
.Lcfu_finished: mov     r0, #0
                add     sp, sp, #8
                ldmfd   sp!, {r4 - r7, pc}

.Lcfu_src_not_aligned:
                bic     r1, r1, #3
USER(           ldrt    r7, [r1], #4)                   @ May fault
                cmp     ip, #2
                bgt     .Lcfu_3fupi
                beq     .Lcfu_2fupi
.Lcfu_1fupi:    subs    r2, r2, #4
                addmi   ip, r2, #4
                bmi     .Lcfu_1nowords
                mov     r3, r7, pull #8
USER(           ldrt    r7, [r1], #4)                   @ May fault
                orr     r3, r3, r7, push #24
                str     r3, [r0], #4
                mov     ip, r1, lsl #32 - PAGE_SHIFT
                rsb     ip, ip, #0
                movs    ip, ip, lsr #32 - PAGE_SHIFT
                beq     .Lcfu_1fupi
                cmp     r2, ip
                movlt   ip, r2
                sub     r2, r2, ip
                subs    ip, ip, #16
                blt     .Lcfu_1rem8lp

.Lcfu_1cpy8lp:  mov     r3, r7, pull #8
                ldmia   r1!, {r4 - r7}                  @ Shouldnt fault
                subs    ip, ip, #16
                orr     r3, r3, r4, push #24
                mov     r4, r4, pull #8
                orr     r4, r4, r5, push #24
                mov     r5, r5, pull #8
                orr     r5, r5, r6, push #24
                mov     r6, r6, pull #8
                orr     r6, r6, r7, push #24
                stmia   r0!, {r3 - r6}
                bpl     .Lcfu_1cpy8lp

.Lcfu_1rem8lp:  tst     ip, #8
                movne   r3, r7, pull #8
                ldmneia r1!, {r4, r7}                   @ Shouldnt fault
                orrne   r3, r3, r4, push #24
                movne   r4, r4, pull #8
                orrne   r4, r4, r7, push #24
                stmneia r0!, {r3 - r4}
                tst     ip, #4
                movne   r3, r7, pull #8
USER(           ldrnet  r7, [r1], #4)                   @ May fault
                orrne   r3, r3, r7, push #24
                strne   r3, [r0], #4
                ands    ip, ip, #3
                beq     .Lcfu_1fupi
.Lcfu_1nowords: mov     r3, r7, get_byte_1
                teq     ip, #0
                beq     .Lcfu_finished
                cmp     ip, #2
                strb    r3, [r0], #1
                movge   r3, r7, get_byte_2
                strgeb  r3, [r0], #1
                movgt   r3, r7, get_byte_3
                strgtb  r3, [r0], #1
                b       .Lcfu_finished

.Lcfu_2fupi:    subs    r2, r2, #4
                addmi   ip, r2, #4
                bmi     .Lcfu_2nowords
                mov     r3, r7, pull #16
USER(           ldrt    r7, [r1], #4)                   @ May fault
                orr     r3, r3, r7, push #16
                str     r3, [r0], #4
                mov     ip, r1, lsl #32 - PAGE_SHIFT
                rsb     ip, ip, #0
                movs    ip, ip, lsr #32 - PAGE_SHIFT
                beq     .Lcfu_2fupi
                cmp     r2, ip
                movlt   ip, r2
                sub     r2, r2, ip
                subs    ip, ip, #16
                blt     .Lcfu_2rem8lp


.Lcfu_2cpy8lp:  mov     r3, r7, pull #16
                ldmia   r1!, {r4 - r7}                  @ Shouldnt fault
                subs    ip, ip, #16
                orr     r3, r3, r4, push #16
                mov     r4, r4, pull #16
                orr     r4, r4, r5, push #16
                mov     r5, r5, pull #16
                orr     r5, r5, r6, push #16
                mov     r6, r6, pull #16
                orr     r6, r6, r7, push #16
                stmia   r0!, {r3 - r6}
                bpl     .Lcfu_2cpy8lp

.Lcfu_2rem8lp:  tst     ip, #8
                movne   r3, r7, pull #16
                ldmneia r1!, {r4, r7}                   @ Shouldnt fault
                orrne   r3, r3, r4, push #16
                movne   r4, r4, pull #16
                orrne   r4, r4, r7, push #16
                stmneia r0!, {r3 - r4}
                tst     ip, #4
                movne   r3, r7, pull #16
USER(           ldrnet  r7, [r1], #4)                   @ May fault
                orrne   r3, r3, r7, push #16
                strne   r3, [r0], #4
                ands    ip, ip, #3
                beq     .Lcfu_2fupi
.Lcfu_2nowords: mov     r3, r7, get_byte_2
                teq     ip, #0
                beq     .Lcfu_finished
                cmp     ip, #2
                strb    r3, [r0], #1
                movge   r3, r7, get_byte_3
                strgeb  r3, [r0], #1
USER(           ldrgtbt r3, [r1], #0)                   @ May fault
                strgtb  r3, [r0], #1
                b       .Lcfu_finished

.Lcfu_3fupi:    subs    r2, r2, #4
                addmi   ip, r2, #4
                bmi     .Lcfu_3nowords
                mov     r3, r7, pull #24
USER(           ldrt    r7, [r1], #4)                   @ May fault
                orr     r3, r3, r7, push #8
                str     r3, [r0], #4
                mov     ip, r1, lsl #32 - PAGE_SHIFT
                rsb     ip, ip, #0
                movs    ip, ip, lsr #32 - PAGE_SHIFT
                beq     .Lcfu_3fupi
                cmp     r2, ip
                movlt   ip, r2
                sub     r2, r2, ip
                subs    ip, ip, #16
                blt     .Lcfu_3rem8lp

.Lcfu_3cpy8lp:  mov     r3, r7, pull #24
                ldmia   r1!, {r4 - r7}                  @ Shouldnt fault
                orr     r3, r3, r4, push #8
                mov     r4, r4, pull #24
                orr     r4, r4, r5, push #8
                mov     r5, r5, pull #24
                orr     r5, r5, r6, push #8
                mov     r6, r6, pull #24
                orr     r6, r6, r7, push #8
                stmia   r0!, {r3 - r6}
                subs    ip, ip, #16
                bpl     .Lcfu_3cpy8lp

.Lcfu_3rem8lp:  tst     ip, #8
                movne   r3, r7, pull #24
                ldmneia r1!, {r4, r7}                   @ Shouldnt fault
                orrne   r3, r3, r4, push #8
                movne   r4, r4, pull #24
                orrne   r4, r4, r7, push #8
                stmneia r0!, {r3 - r4}
                tst     ip, #4
                movne   r3, r7, pull #24
USER(           ldrnet  r7, [r1], #4)                   @ May fault
                orrne   r3, r3, r7, push #8
                strne   r3, [r0], #4
                ands    ip, ip, #3
                beq     .Lcfu_3fupi
.Lcfu_3nowords: mov     r3, r7, get_byte_3
                teq     ip, #0
                beq     .Lcfu_finished
                cmp     ip, #2
                strb    r3, [r0], #1
USER(           ldrgebt r3, [r1], #1)                   @ May fault
                strgeb  r3, [r0], #1
USER(           ldrgtbt r3, [r1], #1)                   @ May fault
                strgtb  r3, [r0], #1
                b       .Lcfu_finished

                .section .fixup,"ax"
                .align  0
                /*
                 * We took an exception.  r0 contains a pointer to
                 * the byte not copied.
                 */
9001:           ldr     r2, [sp], #4                    @ void *to
                sub     r2, r0, r2                      @ bytes copied
                ldr     r1, [sp], #4                    @ unsigned long count
                subs    r4, r1, r2                      @ bytes left to copy
                movne   r1, r4
                blne    __memzero
                mov     r0, r4
                ldmfd   sp!, {r4 - r7, pc}
                .previous