xref: /linux/arch/sparc/lib/bzero.S (revision 03c11eb3b16dc0058589751dfd91f254be2be613)

/* SPDX-License-Identifier: GPL-2.0 */
/* bzero.S: Simple prefetching memset, bzero, and clear_user
 *          implementations.
 *
 * Copyright (C) 2005 David S. Miller <davem@davemloft.net>
 */

#include <linux/export.h>
#include <linux/linkage.h>

	.text

ENTRY(memset) /* %o0=buf, %o1=pat, %o2=len */
	and		%o1, 0xff, %o3
	mov		%o2, %o1
	sllx		%o3, 8, %g1
	or		%g1, %o3, %o2
	sllx		%o2, 16, %g1
	or		%g1, %o2, %o2
	sllx		%o2, 32, %g1
	ba,pt		%xcc, 1f
	 or		%g1, %o2, %o2

ENTRY(__bzero) /* %o0=buf, %o1=len */
	clr		%o2
1:	mov		%o0, %o3
	brz,pn		%o1, __bzero_done
	 cmp		%o1, 16
	bl,pn		%icc, __bzero_tiny
	 prefetch	[%o0 + 0x000], #n_writes
	andcc		%o0, 0x3, %g0
	be,pt		%icc, 2f
1:	 stb		%o2, [%o0 + 0x00]
	add		%o0, 1, %o0
	andcc		%o0, 0x3, %g0
	bne,pn		%icc, 1b
	 sub		%o1, 1, %o1
2:	andcc		%o0, 0x7, %g0
	be,pt		%icc, 3f
	 stw		%o2, [%o0 + 0x00]
	sub		%o1, 4, %o1
	add		%o0, 4, %o0
3:	and		%o1, 0x38, %g1
	cmp		%o1, 0x40
	andn		%o1, 0x3f, %o4
	bl,pn		%icc, 5f
	 and		%o1, 0x7, %o1
	prefetch	[%o0 + 0x040], #n_writes
	prefetch	[%o0 + 0x080], #n_writes
	prefetch	[%o0 + 0x0c0], #n_writes
	prefetch	[%o0 + 0x100], #n_writes
	prefetch	[%o0 + 0x140], #n_writes
4:	prefetch	[%o0 + 0x180], #n_writes
	stx		%o2, [%o0 + 0x00]
	stx		%o2, [%o0 + 0x08]
	stx		%o2, [%o0 + 0x10]
	stx		%o2, [%o0 + 0x18]
	stx		%o2, [%o0 + 0x20]
	stx		%o2, [%o0 + 0x28]
	stx		%o2, [%o0 + 0x30]
	stx		%o2, [%o0 + 0x38]
	subcc		%o4, 0x40, %o4
	bne,pt		%icc, 4b
	 add		%o0, 0x40, %o0
	brz,pn		%g1, 6f
	 nop
5:	stx		%o2, [%o0 + 0x00]
	subcc		%g1, 8, %g1
	bne,pt		%icc, 5b
	 add		%o0, 0x8, %o0
6:	brz,pt		%o1, __bzero_done
	 nop
__bzero_tiny:
1:	stb		%o2, [%o0 + 0x00]
	subcc		%o1, 1, %o1
	bne,pt		%icc, 1b
	 add		%o0, 1, %o0
__bzero_done:
	retl
	 mov		%o3, %o0
ENDPROC(__bzero)
ENDPROC(memset)
EXPORT_SYMBOL(__bzero)
EXPORT_SYMBOL(memset)

#define EX_ST(x,y)		\
98:	x,y;			\
	.section __ex_table,"a";\
	.align 4;		\
	.word 98b, __retl_o1;	\
	.text;			\
	.align 4;

ENTRY(__clear_user) /* %o0=buf, %o1=len */
	brz,pn		%o1, __clear_user_done
	 cmp		%o1, 16
	bl,pn		%icc, __clear_user_tiny
	 EX_ST(prefetcha [%o0 + 0x00] %asi, #n_writes)
	andcc		%o0, 0x3, %g0
	be,pt		%icc, 2f
1:	 EX_ST(stba	%g0, [%o0 + 0x00] %asi)
	add		%o0, 1, %o0
	andcc		%o0, 0x3, %g0
	bne,pn		%icc, 1b
	 sub		%o1, 1, %o1
2:	andcc		%o0, 0x7, %g0
	be,pt		%icc, 3f
	 EX_ST(stwa	%g0, [%o0 + 0x00] %asi)
	sub		%o1, 4, %o1
	add		%o0, 4, %o0
3:	and		%o1, 0x38, %g1
	cmp		%o1, 0x40
	andn		%o1, 0x3f, %o4
	bl,pn		%icc, 5f
	 and		%o1, 0x7, %o1
	EX_ST(prefetcha	[%o0 + 0x040] %asi, #n_writes)
	EX_ST(prefetcha	[%o0 + 0x080] %asi, #n_writes)
	EX_ST(prefetcha	[%o0 + 0x0c0] %asi, #n_writes)
	EX_ST(prefetcha	[%o0 + 0x100] %asi, #n_writes)
	EX_ST(prefetcha	[%o0 + 0x140] %asi, #n_writes)
4:	EX_ST(prefetcha	[%o0 + 0x180] %asi, #n_writes)
	EX_ST(stxa	%g0, [%o0 + 0x00] %asi)
	EX_ST(stxa	%g0, [%o0 + 0x08] %asi)
	EX_ST(stxa	%g0, [%o0 + 0x10] %asi)
	EX_ST(stxa	%g0, [%o0 + 0x18] %asi)
	EX_ST(stxa	%g0, [%o0 + 0x20] %asi)
	EX_ST(stxa	%g0, [%o0 + 0x28] %asi)
	EX_ST(stxa	%g0, [%o0 + 0x30] %asi)
	EX_ST(stxa	%g0, [%o0 + 0x38] %asi)
	subcc		%o4, 0x40, %o4
	bne,pt		%icc, 4b
	 add		%o0, 0x40, %o0
	brz,pn		%g1, 6f
	 nop
5:	EX_ST(stxa	%g0, [%o0 + 0x00] %asi)
	subcc		%g1, 8, %g1
	bne,pt		%icc, 5b
	 add		%o0, 0x8, %o0
6:	brz,pt		%o1, __clear_user_done
	 nop
__clear_user_tiny:
1:	EX_ST(stba	%g0, [%o0 + 0x00] %asi)
	subcc		%o1, 1, %o1
	bne,pt		%icc, 1b
	 add		%o0, 1, %o0
__clear_user_done:
	retl
	 clr		%o0
ENDPROC(__clear_user)
EXPORT_SYMBOL(__clear_user)