x86: Add and enable an arch verson of memmove.

This is from memcpy_32.c in the Linux kernel. There was no copyright header
in the original file either.

Change-Id: Ifd259cb8a87615dce79ed1e551cc4bacb0414b4f
Signed-off-by: Gabe Black <gabeblack@chromium.org>
Reviewed-on: http://review.coreboot.org/3762
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
This commit is contained in:
Gabe Black 2013-07-07 14:08:30 -07:00 committed by Ronald G. Minnich
parent 545c0caac8
commit ccdc005b01
3 changed files with 192 additions and 0 deletions

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@ -5,6 +5,7 @@ config X86_ARCH_OPTIONS
default y
select HAVE_ARCH_MEMSET
select HAVE_ARCH_MEMCPY
select HAVE_ARCH_MEMMOVE
config MARK_GRAPHICS_MEM_WRCOMB
bool "Mark graphics memory as write-combining."

View File

@ -6,6 +6,7 @@ ramstage-y += exception.c
ramstage-$(CONFIG_IOAPIC) += ioapic.c
ramstage-y += memset.c
ramstage-y += memcpy.c
ramstage-y += memmove.c
ramstage-y += ebda.c
ramstage-y += rom_media.c
ramstage-$(CONFIG_COOP_MULTITASKING) += thread.c
@ -15,13 +16,16 @@ romstage-$(CONFIG_EARLY_CONSOLE) += romstage_console.c
romstage-y += cbfs_and_run.c
romstage-y += memset.c
romstage-y += memcpy.c
romstage-y += memmove.c
romstage-y += rom_media.c
smm-y += memset.c
smm-y += memcpy.c
smm-y += memmove.c
smm-y += rom_media.c
rmodules-y += memset.c
rmodules-y += memcpy.c
rmodules-y += memmove.c
$(obj)/arch/x86/lib/console.ramstage.o :: $(obj)/build.h

187
src/arch/x86/lib/memmove.c Normal file
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@ -0,0 +1,187 @@
#include <string.h>
void *memmove(void *dest, const void *src, size_t n)
{
int d0,d1,d2,d3,d4,d5;
char *ret = dest;
__asm__ __volatile__(
/* Handle more 16bytes 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 16byts 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 16byts 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;
}