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 12#include <asm/asmmacro.h> 13#include <asm/page.h> 14#include <asm/export.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) 78EXPORT_SYMBOL(clear_page) 79