mirror of
https://source.denx.de/u-boot/u-boot.git
synced 2025-11-04 10:21:25 +01:00
a5b8722532
Bring in a faster memmove() from Linux 4.7. This speeds up scrolling on the display. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Bin Meng <bmeng.cn@gmail.com> Tested-by: Bin Meng <bmeng.cn@gmail.com>
294 lines
6.5 KiB
C
294 lines
6.5 KiB
C
/*
|
|
* Copyright (C) 1991,1992,1993,1997,1998,2003, 2005 Free Software Foundation, Inc.
|
|
* This file is part of the GNU C Library.
|
|
* Copyright (c) 2011 The Chromium OS Authors.
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0+
|
|
*/
|
|
|
|
/* From glibc-2.14, sysdeps/i386/memset.c */
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/compiler.h>
|
|
#include <asm/string.h>
|
|
|
|
typedef uint32_t op_t;
|
|
|
|
void *memset(void *dstpp, int c, size_t len)
|
|
{
|
|
int d0;
|
|
unsigned long int dstp = (unsigned long int) dstpp;
|
|
|
|
/* This explicit register allocation improves code very much indeed. */
|
|
register op_t x asm("ax");
|
|
|
|
x = (unsigned char) c;
|
|
|
|
/* Clear the direction flag, so filling will move forward. */
|
|
asm volatile("cld");
|
|
|
|
/* This threshold value is optimal. */
|
|
if (len >= 12) {
|
|
/* Fill X with four copies of the char we want to fill with. */
|
|
x |= (x << 8);
|
|
x |= (x << 16);
|
|
|
|
/* Adjust LEN for the bytes handled in the first loop. */
|
|
len -= (-dstp) % sizeof(op_t);
|
|
|
|
/*
|
|
* There are at least some bytes to set. No need to test for
|
|
* LEN == 0 in this alignment loop.
|
|
*/
|
|
|
|
/* Fill bytes until DSTP is aligned on a longword boundary. */
|
|
asm volatile(
|
|
"rep\n"
|
|
"stosb" /* %0, %2, %3 */ :
|
|
"=D" (dstp), "=c" (d0) :
|
|
"0" (dstp), "1" ((-dstp) % sizeof(op_t)), "a" (x) :
|
|
"memory");
|
|
|
|
/* Fill longwords. */
|
|
asm volatile(
|
|
"rep\n"
|
|
"stosl" /* %0, %2, %3 */ :
|
|
"=D" (dstp), "=c" (d0) :
|
|
"0" (dstp), "1" (len / sizeof(op_t)), "a" (x) :
|
|
"memory");
|
|
len %= sizeof(op_t);
|
|
}
|
|
|
|
/* Write the last few bytes. */
|
|
asm volatile(
|
|
"rep\n"
|
|
"stosb" /* %0, %2, %3 */ :
|
|
"=D" (dstp), "=c" (d0) :
|
|
"0" (dstp), "1" (len), "a" (x) :
|
|
"memory");
|
|
|
|
return dstpp;
|
|
}
|
|
|
|
#define OP_T_THRES 8
|
|
#define OPSIZ (sizeof(op_t))
|
|
|
|
#define BYTE_COPY_FWD(dst_bp, src_bp, nbytes) \
|
|
do { \
|
|
int __d0; \
|
|
asm volatile( \
|
|
/* Clear the direction flag, so copying goes forward. */ \
|
|
"cld\n" \
|
|
/* Copy bytes. */ \
|
|
"rep\n" \
|
|
"movsb" : \
|
|
"=D" (dst_bp), "=S" (src_bp), "=c" (__d0) : \
|
|
"0" (dst_bp), "1" (src_bp), "2" (nbytes) : \
|
|
"memory"); \
|
|
} while (0)
|
|
|
|
#define WORD_COPY_FWD(dst_bp, src_bp, nbytes_left, nbytes) \
|
|
do { \
|
|
int __d0; \
|
|
asm volatile( \
|
|
/* Clear the direction flag, so copying goes forward. */ \
|
|
"cld\n" \
|
|
/* Copy longwords. */ \
|
|
"rep\n" \
|
|
"movsl" : \
|
|
"=D" (dst_bp), "=S" (src_bp), "=c" (__d0) : \
|
|
"0" (dst_bp), "1" (src_bp), "2" ((nbytes) / 4) : \
|
|
"memory"); \
|
|
(nbytes_left) = (nbytes) % 4; \
|
|
} while (0)
|
|
|
|
void *memcpy(void *dstpp, const void *srcpp, size_t len)
|
|
{
|
|
unsigned long int dstp = (long int)dstpp;
|
|
unsigned long int srcp = (long int)srcpp;
|
|
|
|
/* Copy from the beginning to the end. */
|
|
|
|
/* If there not too few bytes to copy, use word copy. */
|
|
if (len >= OP_T_THRES) {
|
|
/* Copy just a few bytes to make DSTP aligned. */
|
|
len -= (-dstp) % OPSIZ;
|
|
BYTE_COPY_FWD(dstp, srcp, (-dstp) % OPSIZ);
|
|
|
|
/* Copy from SRCP to DSTP taking advantage of the known
|
|
* alignment of DSTP. Number of bytes remaining is put
|
|
* in the third argument, i.e. in LEN. This number may
|
|
* vary from machine to machine.
|
|
*/
|
|
WORD_COPY_FWD(dstp, srcp, len, len);
|
|
|
|
/* Fall out and copy the tail. */
|
|
}
|
|
|
|
/* There are just a few bytes to copy. Use byte memory operations. */
|
|
BYTE_COPY_FWD(dstp, srcp, len);
|
|
|
|
return dstpp;
|
|
}
|
|
|
|
void *memmove(void *dest, const void *src, size_t n)
|
|
{
|
|
int d0, d1, d2, d3, d4, d5;
|
|
char *ret = dest;
|
|
|
|
__asm__ __volatile__(
|
|
/* Handle more 16 bytes in loop */
|
|
"cmp $0x10, %0\n\t"
|
|
"jb 1f\n\t"
|
|
|
|
/* Decide forward/backward copy mode */
|
|
"cmp %2, %1\n\t"
|
|
"jb 2f\n\t"
|
|
|
|
/*
|
|
* movs instruction have many startup latency
|
|
* so we handle small size by general register.
|
|
*/
|
|
"cmp $680, %0\n\t"
|
|
"jb 3f\n\t"
|
|
/* movs instruction is only good for aligned case */
|
|
"mov %1, %3\n\t"
|
|
"xor %2, %3\n\t"
|
|
"and $0xff, %3\n\t"
|
|
"jz 4f\n\t"
|
|
"3:\n\t"
|
|
"sub $0x10, %0\n\t"
|
|
|
|
/* We gobble 16 bytes forward in each loop */
|
|
"3:\n\t"
|
|
"sub $0x10, %0\n\t"
|
|
"mov 0*4(%1), %3\n\t"
|
|
"mov 1*4(%1), %4\n\t"
|
|
"mov %3, 0*4(%2)\n\t"
|
|
"mov %4, 1*4(%2)\n\t"
|
|
"mov 2*4(%1), %3\n\t"
|
|
"mov 3*4(%1), %4\n\t"
|
|
"mov %3, 2*4(%2)\n\t"
|
|
"mov %4, 3*4(%2)\n\t"
|
|
"lea 0x10(%1), %1\n\t"
|
|
"lea 0x10(%2), %2\n\t"
|
|
"jae 3b\n\t"
|
|
"add $0x10, %0\n\t"
|
|
"jmp 1f\n\t"
|
|
|
|
/* Handle data forward by movs */
|
|
".p2align 4\n\t"
|
|
"4:\n\t"
|
|
"mov -4(%1, %0), %3\n\t"
|
|
"lea -4(%2, %0), %4\n\t"
|
|
"shr $2, %0\n\t"
|
|
"rep movsl\n\t"
|
|
"mov %3, (%4)\n\t"
|
|
"jmp 11f\n\t"
|
|
/* Handle data backward by movs */
|
|
".p2align 4\n\t"
|
|
"6:\n\t"
|
|
"mov (%1), %3\n\t"
|
|
"mov %2, %4\n\t"
|
|
"lea -4(%1, %0), %1\n\t"
|
|
"lea -4(%2, %0), %2\n\t"
|
|
"shr $2, %0\n\t"
|
|
"std\n\t"
|
|
"rep movsl\n\t"
|
|
"mov %3,(%4)\n\t"
|
|
"cld\n\t"
|
|
"jmp 11f\n\t"
|
|
|
|
/* Start to prepare for backward copy */
|
|
".p2align 4\n\t"
|
|
"2:\n\t"
|
|
"cmp $680, %0\n\t"
|
|
"jb 5f\n\t"
|
|
"mov %1, %3\n\t"
|
|
"xor %2, %3\n\t"
|
|
"and $0xff, %3\n\t"
|
|
"jz 6b\n\t"
|
|
|
|
/* Calculate copy position to tail */
|
|
"5:\n\t"
|
|
"add %0, %1\n\t"
|
|
"add %0, %2\n\t"
|
|
"sub $0x10, %0\n\t"
|
|
|
|
/* We gobble 16 bytes backward in each loop */
|
|
"7:\n\t"
|
|
"sub $0x10, %0\n\t"
|
|
|
|
"mov -1*4(%1), %3\n\t"
|
|
"mov -2*4(%1), %4\n\t"
|
|
"mov %3, -1*4(%2)\n\t"
|
|
"mov %4, -2*4(%2)\n\t"
|
|
"mov -3*4(%1), %3\n\t"
|
|
"mov -4*4(%1), %4\n\t"
|
|
"mov %3, -3*4(%2)\n\t"
|
|
"mov %4, -4*4(%2)\n\t"
|
|
"lea -0x10(%1), %1\n\t"
|
|
"lea -0x10(%2), %2\n\t"
|
|
"jae 7b\n\t"
|
|
/* Calculate copy position to head */
|
|
"add $0x10, %0\n\t"
|
|
"sub %0, %1\n\t"
|
|
"sub %0, %2\n\t"
|
|
|
|
/* Move data from 8 bytes to 15 bytes */
|
|
".p2align 4\n\t"
|
|
"1:\n\t"
|
|
"cmp $8, %0\n\t"
|
|
"jb 8f\n\t"
|
|
"mov 0*4(%1), %3\n\t"
|
|
"mov 1*4(%1), %4\n\t"
|
|
"mov -2*4(%1, %0), %5\n\t"
|
|
"mov -1*4(%1, %0), %1\n\t"
|
|
|
|
"mov %3, 0*4(%2)\n\t"
|
|
"mov %4, 1*4(%2)\n\t"
|
|
"mov %5, -2*4(%2, %0)\n\t"
|
|
"mov %1, -1*4(%2, %0)\n\t"
|
|
"jmp 11f\n\t"
|
|
|
|
/* Move data from 4 bytes to 7 bytes */
|
|
".p2align 4\n\t"
|
|
"8:\n\t"
|
|
"cmp $4, %0\n\t"
|
|
"jb 9f\n\t"
|
|
"mov 0*4(%1), %3\n\t"
|
|
"mov -1*4(%1, %0), %4\n\t"
|
|
"mov %3, 0*4(%2)\n\t"
|
|
"mov %4, -1*4(%2, %0)\n\t"
|
|
"jmp 11f\n\t"
|
|
|
|
/* Move data from 2 bytes to 3 bytes */
|
|
".p2align 4\n\t"
|
|
"9:\n\t"
|
|
"cmp $2, %0\n\t"
|
|
"jb 10f\n\t"
|
|
"movw 0*2(%1), %%dx\n\t"
|
|
"movw -1*2(%1, %0), %%bx\n\t"
|
|
"movw %%dx, 0*2(%2)\n\t"
|
|
"movw %%bx, -1*2(%2, %0)\n\t"
|
|
"jmp 11f\n\t"
|
|
|
|
/* Move data for 1 byte */
|
|
".p2align 4\n\t"
|
|
"10:\n\t"
|
|
"cmp $1, %0\n\t"
|
|
"jb 11f\n\t"
|
|
"movb (%1), %%cl\n\t"
|
|
"movb %%cl, (%2)\n\t"
|
|
".p2align 4\n\t"
|
|
"11:"
|
|
: "=&c" (d0), "=&S" (d1), "=&D" (d2),
|
|
"=r" (d3), "=r" (d4), "=r"(d5)
|
|
: "0" (n),
|
|
"1" (src),
|
|
"2" (dest)
|
|
: "memory");
|
|
|
|
return ret;
|
|
}
|