18c2ecf20Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0 */
28c2ecf20Sopenharmony_ci/*
38c2ecf20Sopenharmony_ci * Copyright (C) 1999-2002 Hewlett-Packard Co
48c2ecf20Sopenharmony_ci *	Stephane Eranian <eranian@hpl.hp.com>
58c2ecf20Sopenharmony_ci *	David Mosberger-Tang <davidm@hpl.hp.com>
68c2ecf20Sopenharmony_ci * Copyright (C) 2002 Ken Chen <kenneth.w.chen@intel.com>
78c2ecf20Sopenharmony_ci *
88c2ecf20Sopenharmony_ci * 1/06/01 davidm	Tuned for Itanium.
98c2ecf20Sopenharmony_ci * 2/12/02 kchen	Tuned for both Itanium and McKinley
108c2ecf20Sopenharmony_ci * 3/08/02 davidm	Some more tweaking
118c2ecf20Sopenharmony_ci */
128c2ecf20Sopenharmony_ci
138c2ecf20Sopenharmony_ci#include <asm/asmmacro.h>
148c2ecf20Sopenharmony_ci#include <asm/page.h>
158c2ecf20Sopenharmony_ci#include <asm/export.h>
168c2ecf20Sopenharmony_ci
178c2ecf20Sopenharmony_ci#ifdef CONFIG_ITANIUM
188c2ecf20Sopenharmony_ci# define L3_LINE_SIZE	64	// Itanium L3 line size
198c2ecf20Sopenharmony_ci# define PREFETCH_LINES	9	// magic number
208c2ecf20Sopenharmony_ci#else
218c2ecf20Sopenharmony_ci# define L3_LINE_SIZE	128	// McKinley L3 line size
228c2ecf20Sopenharmony_ci# define PREFETCH_LINES	12	// magic number
238c2ecf20Sopenharmony_ci#endif
248c2ecf20Sopenharmony_ci
258c2ecf20Sopenharmony_ci#define saved_lc	r2
268c2ecf20Sopenharmony_ci#define dst_fetch	r3
278c2ecf20Sopenharmony_ci#define dst1		r8
288c2ecf20Sopenharmony_ci#define dst2		r9
298c2ecf20Sopenharmony_ci#define dst3		r10
308c2ecf20Sopenharmony_ci#define dst4		r11
318c2ecf20Sopenharmony_ci
328c2ecf20Sopenharmony_ci#define dst_last	r31
338c2ecf20Sopenharmony_ci
348c2ecf20Sopenharmony_ciGLOBAL_ENTRY(clear_page)
358c2ecf20Sopenharmony_ci	.prologue
368c2ecf20Sopenharmony_ci	.regstk 1,0,0,0
378c2ecf20Sopenharmony_ci	mov r16 = PAGE_SIZE/L3_LINE_SIZE-1	// main loop count, -1=repeat/until
388c2ecf20Sopenharmony_ci	.save ar.lc, saved_lc
398c2ecf20Sopenharmony_ci	mov saved_lc = ar.lc
408c2ecf20Sopenharmony_ci
418c2ecf20Sopenharmony_ci	.body
428c2ecf20Sopenharmony_ci	mov ar.lc = (PREFETCH_LINES - 1)
438c2ecf20Sopenharmony_ci	mov dst_fetch = in0
448c2ecf20Sopenharmony_ci	adds dst1 = 16, in0
458c2ecf20Sopenharmony_ci	adds dst2 = 32, in0
468c2ecf20Sopenharmony_ci	;;
478c2ecf20Sopenharmony_ci.fetch:	stf.spill.nta [dst_fetch] = f0, L3_LINE_SIZE
488c2ecf20Sopenharmony_ci	adds dst3 = 48, in0		// executing this multiple times is harmless
498c2ecf20Sopenharmony_ci	br.cloop.sptk.few .fetch
508c2ecf20Sopenharmony_ci	;;
518c2ecf20Sopenharmony_ci	addl dst_last = (PAGE_SIZE - PREFETCH_LINES*L3_LINE_SIZE), dst_fetch
528c2ecf20Sopenharmony_ci	mov ar.lc = r16			// one L3 line per iteration
538c2ecf20Sopenharmony_ci	adds dst4 = 64, in0
548c2ecf20Sopenharmony_ci	;;
558c2ecf20Sopenharmony_ci#ifdef CONFIG_ITANIUM
568c2ecf20Sopenharmony_ci	// Optimized for Itanium
578c2ecf20Sopenharmony_ci1:	stf.spill.nta [dst1] = f0, 64
588c2ecf20Sopenharmony_ci	stf.spill.nta [dst2] = f0, 64
598c2ecf20Sopenharmony_ci	cmp.lt p8,p0=dst_fetch, dst_last
608c2ecf20Sopenharmony_ci	;;
618c2ecf20Sopenharmony_ci#else
628c2ecf20Sopenharmony_ci	// Optimized for McKinley
638c2ecf20Sopenharmony_ci1:	stf.spill.nta [dst1] = f0, 64
648c2ecf20Sopenharmony_ci	stf.spill.nta [dst2] = f0, 64
658c2ecf20Sopenharmony_ci	stf.spill.nta [dst3] = f0, 64
668c2ecf20Sopenharmony_ci	stf.spill.nta [dst4] = f0, 128
678c2ecf20Sopenharmony_ci	cmp.lt p8,p0=dst_fetch, dst_last
688c2ecf20Sopenharmony_ci	;;
698c2ecf20Sopenharmony_ci	stf.spill.nta [dst1] = f0, 64
708c2ecf20Sopenharmony_ci	stf.spill.nta [dst2] = f0, 64
718c2ecf20Sopenharmony_ci#endif
728c2ecf20Sopenharmony_ci	stf.spill.nta [dst3] = f0, 64
738c2ecf20Sopenharmony_ci(p8)	stf.spill.nta [dst_fetch] = f0, L3_LINE_SIZE
748c2ecf20Sopenharmony_ci	br.cloop.sptk.few 1b
758c2ecf20Sopenharmony_ci	;;
768c2ecf20Sopenharmony_ci	mov ar.lc = saved_lc		// restore lc
778c2ecf20Sopenharmony_ci	br.ret.sptk.many rp
788c2ecf20Sopenharmony_ciEND(clear_page)
798c2ecf20Sopenharmony_ciEXPORT_SYMBOL(clear_page)
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