1/*
2 * Copyright (C) 1999-2002 Hewlett-Packard Co
3 *	Stephane Eranian <eranian@hpl.hp.com>
4 *	David Mosberger-Tang <davidm@hpl.hp.com>
5 * Copyright (C) 2002 Ken Chen <kenneth.w.chen@intel.com>
6 *
7 * 1/06/01 davidm	Tuned for Itanium.
8 * 2/12/02 kchen	Tuned for both Itanium and McKinley
9 * 3/08/02 davidm	Some more tweaking
10 */
11#include <linux/config.h>
12
13#include <asm/asmmacro.h>
14#include <asm/page.h>
15
16#ifdef CONFIG_ITANIUM
17# define L3_LINE_SIZE	64	// Itanium L3 line size
18# define PREFETCH_LINES	9	// magic number
19#else
20# define L3_LINE_SIZE	128	// McKinley L3 line size
21# define PREFETCH_LINES	12	// magic number
22#endif
23
24#define saved_lc	r2
25#define dst_fetch	r3
26#define dst1		r8
27#define dst2		r9
28#define dst3		r10
29#define dst4		r11
30
31#define dst_last	r31
32
33GLOBAL_ENTRY(clear_page)
34	.prologue
35	.regstk 1,0,0,0
36	mov r16 = PAGE_SIZE/L3_LINE_SIZE-1	// main loop count, -1=repeat/until
37	.save ar.lc, saved_lc
38	mov saved_lc = ar.lc
39
40	.body
41	mov ar.lc = (PREFETCH_LINES - 1)
42	mov dst_fetch = in0
43	adds dst1 = 16, in0
44	adds dst2 = 32, in0
45	;;
46.fetch:	stf.spill.nta [dst_fetch] = f0, L3_LINE_SIZE
47	adds dst3 = 48, in0		// executing this multiple times is harmless
48	br.cloop.sptk.few .fetch
49	;;
50	addl dst_last = (PAGE_SIZE - PREFETCH_LINES*L3_LINE_SIZE), dst_fetch
51	mov ar.lc = r16			// one L3 line per iteration
52	adds dst4 = 64, in0
53	;;
54#ifdef CONFIG_ITANIUM
55	// Optimized for Itanium
561:	stf.spill.nta [dst1] = f0, 64
57	stf.spill.nta [dst2] = f0, 64
58	cmp.lt p8,p0=dst_fetch, dst_last
59	;;
60#else
61	// Optimized for McKinley
621:	stf.spill.nta [dst1] = f0, 64
63	stf.spill.nta [dst2] = f0, 64
64	stf.spill.nta [dst3] = f0, 64
65	stf.spill.nta [dst4] = f0, 128
66	cmp.lt p8,p0=dst_fetch, dst_last
67	;;
68	stf.spill.nta [dst1] = f0, 64
69	stf.spill.nta [dst2] = f0, 64
70#endif
71	stf.spill.nta [dst3] = f0, 64
72(p8)	stf.spill.nta [dst_fetch] = f0, L3_LINE_SIZE
73	br.cloop.sptk.few 1b
74	;;
75	mov ar.lc = saved_lc		// restore lc
76	br.ret.sptk.many rp
77END(clear_page)
78