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/*
 * linux/arch/arm/lib/csumpartialcopy.S
 *
 * Copyright (C) 1995-1998 Russell King
 */
#include <linux/linkage.h>
#include <asm/assembler.h>

		.text

/* Function: __u32 csum_partial_copy_nocheck(const char *src, char *dst, int len, __u32 sum)
 * Params  : r0 = src, r1 = dst, r2 = len, r3 = checksum
 * Returns : r0 = new checksum
 */
ENTRY(csum_partial_copy_nocheck)
		mov	ip, sp
		stmfd	sp!, {r4 - r8, fp, ip, lr, pc}
		sub	fp, ip, #4
		cmp	r2, #4
		blt	Ltoo_small
		tst	r1, #2			@ Test destination alignment
		beq	Ldst_aligned
		ldrb	ip, [r0], #1
		ldrb	r8, [r0], #1
		subs	r2, r2, #2		@ We do not know if SRC is aligned...
		orr	ip, ip, r8, lsl #8
		adds	r3, r3, ip
		adcs	r3, r3, #0
		strb	ip, [r1], #1
		mov	ip, ip, lsr #8
		strb	ip, [r1], #1		@ Destination now aligned
Ldst_aligned:	tst	r0, #3
		bne	Lsrc_not_aligned
		adds	r3, r3, #0
		bics	ip, r2, #15		@ Routine for src & dst aligned
		beq	3f
1:		ldmia	r0!, {r4, r5, r6, r7}
		stmia	r1!, {r4, r5, r6, r7}
		adcs	r3, r3, r4
		adcs	r3, r3, r5
		adcs	r3, r3, r6
		adcs	r3, r3, r7
		sub	ip, ip, #16
		teq	ip, #0
		bne	1b
3:		ands	ip, r2, #12
		beq	5f
		tst	ip, #8
		beq	4f
		ldmia	r0!, {r4, r5}
		stmia	r1!, {r4, r5}
		adcs	r3, r3, r4
		adcs	r3, r3, r5
		tst	ip, #4
		beq	5f
4:		ldr	r4, [r0], #4
		str	r4, [r1], #4
		adcs	r3, r3, r4
5:		ands	r2, r2, #3
		adceq	r0, r3, #0
		LOADREGS(eqea,fp,{r4 - r8, fp, sp, pc})
		ldr	r4, [r0], #4
		tst	r2, #2
		beq	Lexit_r4
		adcs	r3, r3, r4, lsl #16
		strb	r4, [r1], #1
		mov	r4, r4, lsr #8
		strb	r4, [r1], #1
		mov	r4, r4, lsr #8
		b	Lexit_r4

Ltoo_small:	teq	r2, #0
		LOADREGS(eqea,fp,{r4 - r8, fp, sp, pc})
		cmp	r2, #2
		blt	Ltoo_small1
		ldrb	ip, [r0], #1
		ldrb	r8, [r0], #1
		orr	ip, ip, r8, lsl #8
		adds	r3, r3, ip
		strb	ip, [r1], #1
		strb	r8, [r1], #1
		tst	r2, #1
Ltoo_small1:	ldrneb	r4, [r0], #1
Lexit_r4:	tst	r2, #1
		strneb	r4, [r1], #1
		andne	r4, r4, #255
		adcnes	r3, r3, r4
		adcs	r0, r3, #0
		LOADREGS(ea,fp,{r4 - r8, fp, sp, pc})

Lsrc_not_aligned:
		cmp	r2, #4
		blt	Ltoo_small
		and	ip, r0, #3
		bic	r0, r0, #3
		ldr	r4, [r0], #4
		cmp	ip, #2
		beq	Lsrc2_aligned
		bhi	Lsrc3_aligned
		mov	r4, r4, lsr #8
		adds	r3, r3, #0
		bics	ip, r2, #15
		beq	2f
1:		ldmia	r0!, {r5, r6, r7, r8}
		orr	r4, r4, r5, lsl #24
		mov	r5, r5, lsr #8
		orr	r5, r5, r6, lsl #24
		mov	r6, r6, lsr #8
		orr	r6, r6, r7, lsl #24
		mov	r7, r7, lsr #8
		orr	r7, r7, r8, lsl #24
		stmia	r1!, {r4, r5, r6, r7}
		adcs	r3, r3, r4
		adcs	r3, r3, r5
		adcs	r3, r3, r6
		adcs	r3, r3, r7
		mov	r4, r8, lsr #8
		sub	ip, ip, #16
		teq	ip, #0
		bne	1b
2:		ands	ip, r2, #12
		beq	4f
		tst	ip, #8
		beq	3f
		ldmia	r0!, {r5, r6}
		orr	r4, r4, r5, lsl #24
		mov	r5, r5, lsr #8
		orr	r5, r5, r6, lsl #24
		stmia	r1!, {r4, r5}
		adcs	r3, r3, r4
		adcs	r3, r3, r5
		mov	r4, r6, lsr #8
		tst	ip, #4
		beq	4f
3:		ldr	r5, [r0], #4
		orr	r4, r4, r5, lsl #24
		str	r4, [r1], #4
		adcs	r3, r3, r4
		mov	r4, r5, lsr #8
4:		ands	r2, r2, #3
		adceq	r0, r3, #0
		LOADREGS(eqea,fp,{r4 - r8, fp, sp, pc})
		tst	r2, #2
		beq	Lexit_r4
		adcs	r3, r3, r4, lsl #16
		strb	r4, [r1], #1
		mov	r4, r4, lsr #8
		strb	r4, [r1], #1
		mov	r4, r4, lsr #8
		b	Lexit_r4

Lsrc2_aligned:	mov	r4, r4, lsr #16
		adds	r3, r3, #0
		bics	ip, r2, #15
		beq	2f
1:		ldmia	r0!, {r5, r6, r7, r8}
		orr	r4, r4, r5, lsl #16
		mov	r5, r5, lsr #16
		orr	r5, r5, r6, lsl #16
		mov	r6, r6, lsr #16
		orr	r6, r6, r7, lsl #16
		mov	r7, r7, lsr #16
		orr	r7, r7, r8, lsl #16
		stmia	r1!, {r4, r5, r6, r7}
		adcs	r3, r3, r4
		adcs	r3, r3, r5
		adcs	r3, r3, r6
		adcs	r3, r3, r7
		mov	r4, r8, lsr #16
		sub	ip, ip, #16
		teq	ip, #0
		bne	1b
2:		ands	ip, r2, #12
		beq	4f
		tst	ip, #8
		beq	3f
		ldmia	r0!, {r5, r6}
		orr	r4, r4, r5, lsl #16
		mov	r5, r5, lsr #16
		orr	r5, r5, r6, lsl #16
		stmia	r1!, {r4, r5}
		adcs	r3, r3, r4
		adcs	r3, r3, r5
		mov	r4, r6, lsr #16
		tst	ip, #4
		beq	4f
3:		ldr	r5, [r0], #4
		orr	r4, r4, r5, lsl #16
		str	r4, [r1], #4
		adcs	r3, r3, r4
		mov	r4, r5, lsr #16
4:		ands	r2, r2, #3
		adceq	r0, r3, #0
		LOADREGS(eqea,fp,{r4 - r8, fp, sp, pc})
		tst	r2, #2
		beq	Lexit_r4
		adcs	r3, r3, r4, lsl #16
		strb	r4, [r1], #1
		mov	r4, r4, lsr #8
		strb	r4, [r1], #1
		ldrb	r4, [r0], #1
		b	Lexit_r4

Lsrc3_aligned:	mov	r4, r4, lsr #24
		adds	r3, r3, #0
		bics	ip, r2, #15
		beq	2f
1:		ldmia	r0!, {r5, r6, r7, r8}
		orr	r4, r4, r5, lsl #8
		mov	r5, r5, lsr #24
		orr	r5, r5, r6, lsl #8
		mov	r6, r6, lsr #24
		orr	r6, r6, r7, lsl #8
		mov	r7, r7, lsr #24
		orr	r7, r7, r8, lsl #8
		stmia	r1!, {r4, r5, r6, r7}
		adcs	r3, r3, r4
		adcs	r3, r3, r5
		adcs	r3, r3, r6
		adcs	r3, r3, r7
		mov	r4, r8, lsr #24
		sub	ip, ip, #16
		teq	ip, #0
		bne	1b
2:		ands	ip, r2, #12
		beq	4f
		tst	ip, #8
		beq	3f
		ldmia	r0!, {r5, r6}
		orr	r4, r4, r5, lsl #8
		mov	r5, r5, lsr #24
		orr	r5, r5, r6, lsl #8
		stmia	r1!, {r4, r5}
		adcs	r3, r3, r4
		adcs	r3, r3, r5
		mov	r4, r6, lsr #24
		tst	ip, #4
		beq	4f
3:		ldr	r5, [r0], #4
		orr	r4, r4, r5, lsl #8
		str	r4, [r1], #4
		adcs	r3, r3, r4
		mov	r4, r5, lsr #24
4:		ands	r2, r2, #3
		adceq	r0, r3, #0
		LOADREGS(eqea,fp,{r4 - r8, fp, sp, pc})
		tst	r2, #2
		beq	Lexit_r4
		adcs	r3, r3, r4, lsl #16
		strb	r4, [r1], #1
		ldr	r4, [r0], #4
		strb	r4, [r1], #1
		adcs	r3, r3, r4, lsl #24
		mov	r4, r4, lsr #8
		b	Lexit_r4