| /* SPDX-License-Identifier: GPL-2.0-only */ |
| /* This file is part of the coreboot project. */ |
| /* Based on linux/arch/arm/lib/memmove.S */ |
| |
| #include <arch/asm.h> |
| #include "asmlib.h" |
| |
| /* |
| * Prototype: void *memmove(void *dest, const void *src, size_t n); |
| * |
| * Note: |
| * |
| * If the memory regions don't overlap, we simply branch to memcpy which is |
| * normally a bit faster. Otherwise the copy is done going downwards. This |
| * is a transposition of the code from copy_template.S but with the copy |
| * occurring in the opposite direction. |
| */ |
| |
| ENTRY(memmove) |
| |
| subs ip, r0, r1 |
| cmphi r2, ip |
| bls memcpy |
| |
| stmfd sp!, {r0, r4, lr} |
| add r1, r1, r2 |
| add r0, r0, r2 |
| subs r2, r2, #4 |
| blt 8f |
| ands ip, r0, #3 |
| PLD( pld [r1, #-4] ) |
| bne 9f |
| ands ip, r1, #3 |
| bne 10f |
| |
| 1: subs r2, r2, #(28) |
| stmfd sp!, {r5 - r8} |
| blt 5f |
| |
| CALGN( ands ip, r0, #31 ) |
| CALGN( sbcnes r4, ip, r2 ) @ C is always set here |
| CALGN( bcs 2f ) |
| CALGN( adr r4, 6f ) |
| CALGN( subs r2, r2, ip ) @ C is set here |
| CALGN( rsb ip, ip, #32 ) |
| CALGN( add pc, r4, ip ) |
| |
| PLD( pld [r1, #-4] ) |
| 2: PLD( subs r2, r2, #96 ) |
| PLD( pld [r1, #-32] ) |
| PLD( blt 4f ) |
| PLD( pld [r1, #-64] ) |
| PLD( pld [r1, #-96] ) |
| |
| 3: PLD( pld [r1, #-128] ) |
| 4: ldmdb r1!, {r3, r4, r5, r6, r7, r8, ip, lr} |
| subs r2, r2, #32 |
| stmdb r0!, {r3, r4, r5, r6, r7, r8, ip, lr} |
| bge 3b |
| PLD( cmn r2, #96 ) |
| PLD( bge 4b ) |
| |
| 5: ands ip, r2, #28 |
| rsb ip, ip, #32 |
| addne pc, pc, ip @ C is always clear here |
| b 7f |
| 6: W(nop) |
| W(ldr) r3, [r1, #-4]! |
| W(ldr) r4, [r1, #-4]! |
| W(ldr) r5, [r1, #-4]! |
| W(ldr) r6, [r1, #-4]! |
| W(ldr) r7, [r1, #-4]! |
| W(ldr) r8, [r1, #-4]! |
| W(ldr) lr, [r1, #-4]! |
| |
| add pc, pc, ip |
| nop |
| W(nop) |
| W(str) r3, [r0, #-4]! |
| W(str) r4, [r0, #-4]! |
| W(str) r5, [r0, #-4]! |
| W(str) r6, [r0, #-4]! |
| W(str) r7, [r0, #-4]! |
| W(str) r8, [r0, #-4]! |
| W(str) lr, [r0, #-4]! |
| |
| CALGN( bcs 2b ) |
| |
| 7: ldmfd sp!, {r5 - r8} |
| |
| 8: movs r2, r2, lsl #31 |
| ldrneb r3, [r1, #-1]! |
| ldrcsb r4, [r1, #-1]! |
| ldrcsb ip, [r1, #-1] |
| strneb r3, [r0, #-1]! |
| strcsb r4, [r0, #-1]! |
| strcsb ip, [r0, #-1] |
| ldmfd sp!, {r0, r4, pc} |
| |
| 9: cmp ip, #2 |
| ldrgtb r3, [r1, #-1]! |
| ldrgeb r4, [r1, #-1]! |
| ldrb lr, [r1, #-1]! |
| strgtb r3, [r0, #-1]! |
| strgeb r4, [r0, #-1]! |
| subs r2, r2, ip |
| strb lr, [r0, #-1]! |
| blt 8b |
| ands ip, r1, #3 |
| beq 1b |
| |
| 10: bic r1, r1, #3 |
| cmp ip, #2 |
| ldr r3, [r1, #0] |
| beq 17f |
| blt 18f |
| |
| |
| .macro backward_copy_shift push pull |
| |
| subs r2, r2, #28 |
| blt 14f |
| |
| CALGN( ands ip, r0, #31 ) |
| CALGN( sbcnes r4, ip, r2 ) @ C is always set here |
| CALGN( subcc r2, r2, ip ) |
| CALGN( bcc 15f ) |
| |
| 11: stmfd sp!, {r5 - r9} |
| |
| PLD( pld [r1, #-4] ) |
| PLD( subs r2, r2, #96 ) |
| PLD( pld [r1, #-32] ) |
| PLD( blt 13f ) |
| PLD( pld [r1, #-64] ) |
| PLD( pld [r1, #-96] ) |
| |
| 12: PLD( pld [r1, #-128] ) |
| 13: ldmdb r1!, {r7, r8, r9, ip} |
| mov lr, r3, push #\push |
| subs r2, r2, #32 |
| ldmdb r1!, {r3, r4, r5, r6} |
| orr lr, lr, ip, pull #\pull |
| mov ip, ip, push #\push |
| orr ip, ip, r9, pull #\pull |
| mov r9, r9, push #\push |
| orr r9, r9, r8, pull #\pull |
| mov r8, r8, push #\push |
| orr r8, r8, r7, pull #\pull |
| mov r7, r7, push #\push |
| orr r7, r7, r6, pull #\pull |
| mov r6, r6, push #\push |
| orr r6, r6, r5, pull #\pull |
| mov r5, r5, push #\push |
| orr r5, r5, r4, pull #\pull |
| mov r4, r4, push #\push |
| orr r4, r4, r3, pull #\pull |
| stmdb r0!, {r4 - r9, ip, lr} |
| bge 12b |
| PLD( cmn r2, #96 ) |
| PLD( bge 13b ) |
| |
| ldmfd sp!, {r5 - r9} |
| |
| 14: ands ip, r2, #28 |
| beq 16f |
| |
| 15: mov lr, r3, push #\push |
| ldr r3, [r1, #-4]! |
| subs ip, ip, #4 |
| orr lr, lr, r3, pull #\pull |
| str lr, [r0, #-4]! |
| bgt 15b |
| CALGN( cmp r2, #0 ) |
| CALGN( bge 11b ) |
| |
| 16: add r1, r1, #(\pull / 8) |
| b 8b |
| |
| .endm |
| |
| |
| backward_copy_shift push=8 pull=24 |
| |
| 17: backward_copy_shift push=16 pull=16 |
| |
| 18: backward_copy_shift push=24 pull=8 |
| |
| ENDPROC(memmove) |