From a27ad9b5cf49fea1a55141868f4bf02c2d91bfc1 Mon Sep 17 00:00:00 2001
From: Ralf Baechle <ralf@linux-mips.org>
Date: Wed, 26 Jul 2000 21:06:03 +0000
Subject: Optimize andes_clear_page() and andes_copy_page() with prefetch
 operations.  While those routines are now 30% - 60% faster it turned out that
 their influence on realworld applications and benchmars is fairly low; I saw
 an improvment of ~ 3% for lmbench exec sh and even less for other benches.

---
 arch/mips64/mm/andes.c | 39 +++++++++++++++++++++++----------------
 1 file changed, 23 insertions(+), 16 deletions(-)

(limited to 'arch/mips64/mm')

diff --git a/arch/mips64/mm/andes.c b/arch/mips64/mm/andes.c
index 3dfabd169..9c6fb5fa4 100644
--- a/arch/mips64/mm/andes.c
+++ b/arch/mips64/mm/andes.c
@@ -1,5 +1,4 @@
-/* $Id: andes.c,v 1.7 2000/03/13 22:43:25 kanoj Exp $
- *
+/*
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
@@ -24,14 +23,18 @@
 				     "nop; nop; nop; nop; nop; nop;\n\t" \
 				     ".set reorder\n\t")
 
-/* R10000 has no Create_Dirty type cacheops.  */
+/*
+ * This version has been tuned on an Origin.  For other machines the arguments
+ * of the pref instructin may have to be tuned differently.
+ */
 static void andes_clear_page(void * page)
 {
 	__asm__ __volatile__(
 		".set\tnoreorder\n\t"
 		".set\tnoat\n\t"
 		"daddiu\t$1,%0,%2\n"
-		"1:\tsd\t$0,(%0)\n\t"
+		"1:\tpref 7,512(%0)\n\t"
+		"sd\t$0,(%0)\n\t"
 		"sd\t$0,8(%0)\n\t"
 		"sd\t$0,16(%0)\n\t"
 		"sd\t$0,24(%0)\n\t"
@@ -48,36 +51,40 @@ static void andes_clear_page(void * page)
 		:"$1", "memory");
 }
 
+/* R10000 has no Create_Dirty type cacheops.  */
 static void andes_copy_page(void * to, void * from)
 {
-	unsigned long dummy1, dummy2, reg1, reg2;
+	unsigned long dummy1, dummy2, reg1, reg2, reg3, reg4;
 
 	__asm__ __volatile__(
 		".set\tnoreorder\n\t"
 		".set\tnoat\n\t"
-		"daddiu\t$1,%0,%6\n"
-		"1:\tld\t%2,(%1)\n\t"
+		"daddiu\t$1,%0,%8\n"
+		"1:\tpref\t0,2*128(%1)\n\t"
+		"pref\t1,2*128(%0)\n\t"
+		"ld\t%2,(%1)\n\t"
 		"ld\t%3,8(%1)\n\t"
+		"ld\t%4,16(%1)\n\t"
+		"ld\t%5,24(%1)\n\t"
 		"sd\t%2,(%0)\n\t"
 		"sd\t%3,8(%0)\n\t"
-		"ld\t%2,16(%1)\n\t"
-		"ld\t%3,24(%1)\n\t"
-		"sd\t%2,16(%0)\n\t"
-		"sd\t%3,24(%0)\n\t"
+		"sd\t%4,16(%0)\n\t"
+		"sd\t%5,24(%0)\n\t"
 		"daddiu\t%0,64\n\t"
 		"daddiu\t%1,64\n\t"
 		"ld\t%2,-32(%1)\n\t"
 		"ld\t%3,-24(%1)\n\t"
+		"ld\t%4,-16(%1)\n\t"
+		"ld\t%5,-8(%1)\n\t"
 		"sd\t%2,-32(%0)\n\t"
 		"sd\t%3,-24(%0)\n\t"
-		"ld\t%2,-16(%1)\n\t"
-		"ld\t%3,-8(%1)\n\t"
-		"sd\t%2,-16(%0)\n\t"
+		"sd\t%4,-16(%0)\n\t"
 		"bne\t$1,%0,1b\n\t"
-		" sd\t%3,-8(%0)\n\t"
+		" sd\t%5,-8(%0)\n\t"
 		".set\tat\n\t"
 		".set\treorder"
-		:"=r" (dummy1), "=r" (dummy2), "=&r" (reg1), "=&r" (reg2)
+		:"=r" (dummy1), "=r" (dummy2), "=&r" (reg1), "=&r" (reg2),
+		 "=&r" (reg3), "=&r" (reg4)
 		:"0" (to), "1" (from), "I" (PAGE_SIZE));
 }
 
-- 
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