[deliverable/linux.git] / arch / arm64 / lib / copy_page.S

/*
 * Copyright (C) 2012 ARM Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/linkage.h>
#include <linux/const.h>
#include <asm/assembler.h>
#include <asm/page.h>
#include <asm/cpufeature.h>
#include <asm/alternative.h>

/*
 * Copy a page from src to dest (both are page aligned)
 *
 * Parameters:
 *	x0 - dest
 *	x1 - src
 */
ENTRY(copy_page)
alternative_if_not ARM64_HAS_NO_HW_PREFETCH
	nop
	nop
alternative_else
	# Prefetch two cache lines ahead.
	prfm    pldl1strm, [x1, #128]
	prfm    pldl1strm, [x1, #256]
alternative_endif

	ldp	x2, x3, [x1]
	ldp	x4, x5, [x1, #16]
	ldp	x6, x7, [x1, #32]
	ldp	x8, x9, [x1, #48]
	ldp	x10, x11, [x1, #64]
	ldp	x12, x13, [x1, #80]
	ldp	x14, x15, [x1, #96]
	ldp	x16, x17, [x1, #112]

	mov	x18, #(PAGE_SIZE - 128)
	add	x1, x1, #128
1:
	subs	x18, x18, #128

alternative_if_not ARM64_HAS_NO_HW_PREFETCH
	nop
alternative_else
	prfm    pldl1strm, [x1, #384]
alternative_endif

	stnp	x2, x3, [x0]
	ldp	x2, x3, [x1]
	stnp	x4, x5, [x0, #16]
	ldp	x4, x5, [x1, #16]
	stnp	x6, x7, [x0, #32]
	ldp	x6, x7, [x1, #32]
	stnp	x8, x9, [x0, #48]
	ldp	x8, x9, [x1, #48]
	stnp	x10, x11, [x0, #64]
	ldp	x10, x11, [x1, #64]
	stnp	x12, x13, [x0, #80]
	ldp	x12, x13, [x1, #80]
	stnp	x14, x15, [x0, #96]
	ldp	x14, x15, [x1, #96]
	stnp	x16, x17, [x0, #112]
	ldp	x16, x17, [x1, #112]

	add	x0, x0, #128
	add	x1, x1, #128

	b.gt	1b

	stnp	x2, x3, [x0]
	stnp	x4, x5, [x0, #16]
	stnp	x6, x7, [x0, #32]
	stnp	x8, x9, [x0, #48]
	stnp	x10, x11, [x0, #64]
	stnp	x12, x13, [x0, #80]
	stnp	x14, x15, [x0, #96]
	stnp	x16, x17, [x0, #112]

	ret
ENDPROC(copy_page)
Commit	Line	Data
f27bb139 MZ	1	/*
	2	* Copyright (C) 2012 ARM Ltd.
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*
	13	* You should have received a copy of the GNU General Public License
	14	* along with this program. If not, see <http://www.gnu.org/licenses/>.
	15	*/
	16
	17	#include <linux/linkage.h>
	18	#include <linux/const.h>
	19	#include <asm/assembler.h>
	20	#include <asm/page.h>
60e0a09d AP	21	#include <asm/cpufeature.h>
60e0a09d AP	22	#include <asm/alternative.h>
f27bb139 MZ	23
	24	/*
	25	* Copy a page from src to dest (both are page aligned)
	26	*
	27	* Parameters:
	28	* x0 - dest
	29	* x1 - src
	30	*/
	31	ENTRY(copy_page)
60e0a09d AP	32	alternative_if_not ARM64_HAS_NO_HW_PREFETCH
	33	nop
	34	nop
	35	alternative_else
	36	# Prefetch two cache lines ahead.
	37	prfm pldl1strm, [x1, #128]
	38	prfm pldl1strm, [x1, #256]
	39	alternative_endif
	40
223e23e8	41	ldp x2, x3, [x1]
f27bb139 MZ	42	ldp x4, x5, [x1, #16]
	43	ldp x6, x7, [x1, #32]
	44	ldp x8, x9, [x1, #48]
223e23e8 WD	45	ldp x10, x11, [x1, #64]
	46	ldp x12, x13, [x1, #80]
	47	ldp x14, x15, [x1, #96]
	48	ldp x16, x17, [x1, #112]
	49
	50	mov x18, #(PAGE_SIZE - 128)
	51	add x1, x1, #128
	52	1:
	53	subs x18, x18, #128
	54
60e0a09d AP	55	alternative_if_not ARM64_HAS_NO_HW_PREFETCH
	56	nop
	57	alternative_else
	58	prfm pldl1strm, [x1, #384]
	59	alternative_endif
	60
f27bb139	61	stnp x2, x3, [x0]
223e23e8	62	ldp x2, x3, [x1]
f27bb139	63	stnp x4, x5, [x0, #16]
223e23e8	64	ldp x4, x5, [x1, #16]
f27bb139	65	stnp x6, x7, [x0, #32]
223e23e8	66	ldp x6, x7, [x1, #32]
f27bb139	67	stnp x8, x9, [x0, #48]
223e23e8 WD	68	ldp x8, x9, [x1, #48]
	69	stnp x10, x11, [x0, #64]
	70	ldp x10, x11, [x1, #64]
	71	stnp x12, x13, [x0, #80]
	72	ldp x12, x13, [x1, #80]
	73	stnp x14, x15, [x0, #96]
	74	ldp x14, x15, [x1, #96]
	75	stnp x16, x17, [x0, #112]
	76	ldp x16, x17, [x1, #112]
	77
	78	add x0, x0, #128
	79	add x1, x1, #128
	80
	81	b.gt 1b
	82
	83	stnp x2, x3, [x0]
	84	stnp x4, x5, [x0, #16]
	85	stnp x6, x7, [x0, #32]
	86	stnp x8, x9, [x0, #48]
	87	stnp x10, x11, [x0, #64]
	88	stnp x12, x13, [x0, #80]
	89	stnp x14, x15, [x0, #96]
	90	stnp x16, x17, [x0, #112]
	91
f27bb139 MZ	92	ret
f27bb139 MZ	93	ENDPROC(copy_page)