| David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 2 | /* |
| 3 | * linux/arch/arm/lib/copypage.S |
| 4 | * |
| 5 | * Copyright (C) 1995-1999 Russell King |
| 6 | * |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 7 | * ASM optimised string functions |
| 8 | */ |
| 9 | #include <linux/linkage.h> |
| 10 | #include <asm/assembler.h> |
| 11 | #include <asm/asm-offsets.h> |
| 12 | #include <asm/cache.h> |
| 13 | |
| 14 | #define COPY_COUNT (PAGE_SZ / (2 * L1_CACHE_BYTES) PLD( -1 )) |
| 15 | |
| 16 | .text |
| 17 | .align 5 |
| 18 | /* |
| 19 | * StrongARM optimised copy_page routine |
| 20 | * now 1.78bytes/cycle, was 1.60 bytes/cycle (50MHz bus -> 89MB/s) |
| 21 | * Note that we probably achieve closer to the 100MB/s target with |
| 22 | * the core clock switching. |
| 23 | */ |
| 24 | ENTRY(copy_page) |
| 25 | stmfd sp!, {r4, lr} @ 2 |
| 26 | PLD( pld [r1, #0] ) |
| 27 | PLD( pld [r1, #L1_CACHE_BYTES] ) |
| 28 | mov r2, #COPY_COUNT @ 1 |
| 29 | ldmia r1!, {r3, r4, ip, lr} @ 4+1 |
| 30 | 1: PLD( pld [r1, #2 * L1_CACHE_BYTES]) |
| 31 | PLD( pld [r1, #3 * L1_CACHE_BYTES]) |
| 32 | 2: |
| 33 | .rept (2 * L1_CACHE_BYTES / 16 - 1) |
| 34 | stmia r0!, {r3, r4, ip, lr} @ 4 |
| 35 | ldmia r1!, {r3, r4, ip, lr} @ 4 |
| 36 | .endr |
| 37 | subs r2, r2, #1 @ 1 |
| 38 | stmia r0!, {r3, r4, ip, lr} @ 4 |
| David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 39 | ldmiagt r1!, {r3, r4, ip, lr} @ 4 |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 40 | bgt 1b @ 1 |
| David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 41 | PLD( ldmiaeq r1!, {r3, r4, ip, lr} ) |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 42 | PLD( beq 2b ) |
| 43 | ldmfd sp!, {r4, pc} @ 3 |
| 44 | ENDPROC(copy_page) |