1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 1999-2002 Hewlett-Packard Co 4 * Stephane Eranian <eranian@hpl.hp.com> 5 * David Mosberger-Tang <davidm@hpl.hp.com> 6 * Copyright (C) 2002 Ken Chen <kenneth.w.chen@intel.com> 7 * 8 * 1/06/01 davidm Tuned for Itanium. 9 * 2/12/02 kchen Tuned for both Itanium and McKinley 10 * 3/08/02 davidm Some more tweaking 11 */ 12 13 #include <asm/asmmacro.h> 14 #include <asm/page.h> 15 #include <asm/export.h> 16 17 #ifdef CONFIG_ITANIUM 18 # define L3_LINE_SIZE 64 // Itanium L3 line size 19 # define PREFETCH_LINES 9 // magic number 20 #else 21 # define L3_LINE_SIZE 128 // McKinley L3 line size 22 # define PREFETCH_LINES 12 // magic number 23 #endif 24 25 #define saved_lc r2 26 #define dst_fetch r3 27 #define dst1 r8 28 #define dst2 r9 29 #define dst3 r10 30 #define dst4 r11 31 32 #define dst_last r31 33 34 GLOBAL_ENTRY(clear_page) 35 .prologue 36 .regstk 1,0,0,0 37 mov r16 = PAGE_SIZE/L3_LINE_SIZE-1 // main loop count, -1=repeat/until 38 .save ar.lc, saved_lc 39 mov saved_lc = ar.lc 40 41 .body 42 mov ar.lc = (PREFETCH_LINES - 1) 43 mov dst_fetch = in0 44 adds dst1 = 16, in0 45 adds dst2 = 32, in0 46 ;; 47 .fetch: stf.spill.nta [dst_fetch] = f0, L3_LINE_SIZE 48 adds dst3 = 48, in0 // executing this multiple times is harmless 49 br.cloop.sptk.few .fetch 50 ;; 51 addl dst_last = (PAGE_SIZE - PREFETCH_LINES*L3_LINE_SIZE), dst_fetch 52 mov ar.lc = r16 // one L3 line per iteration 53 adds dst4 = 64, in0 54 ;; 55 #ifdef CONFIG_ITANIUM 56 // Optimized for Itanium 57 1: stf.spill.nta [dst1] = f0, 64 58 stf.spill.nta [dst2] = f0, 64 59 cmp.lt p8,p0=dst_fetch, dst_last 60 ;; 61 #else 62 // Optimized for McKinley 63 1: stf.spill.nta [dst1] = f0, 64 64 stf.spill.nta [dst2] = f0, 64 65 stf.spill.nta [dst3] = f0, 64 66 stf.spill.nta [dst4] = f0, 128 67 cmp.lt p8,p0=dst_fetch, dst_last 68 ;; 69 stf.spill.nta [dst1] = f0, 64 70 stf.spill.nta [dst2] = f0, 64 71 #endif 72 stf.spill.nta [dst3] = f0, 64 73 (p8) stf.spill.nta [dst_fetch] = f0, L3_LINE_SIZE 74 br.cloop.sptk.few 1b 75 ;; 76 mov ar.lc = saved_lc // restore lc 77 br.ret.sptk.many rp 78 END(clear_page) 79 EXPORT_SYMBOL(clear_page) 80