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-rw-r--r--arch/um/sys-ppc/misc.S116
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diff --git a/arch/um/sys-ppc/misc.S b/arch/um/sys-ppc/misc.S
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+/*
+ * This file contains miscellaneous low-level functions.
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
+ * and Paul Mackerras.
+ *
+ * A couple of functions stolen from arch/ppc/kernel/misc.S for UML
+ * by Chris Emerson.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <linux/config.h>
+#include <asm/processor.h>
+#include "ppc_asm.h"
+
+#if defined(CONFIG_4xx) || defined(CONFIG_8xx)
+#define CACHE_LINE_SIZE 16
+#define LG_CACHE_LINE_SIZE 4
+#define MAX_COPY_PREFETCH 1
+#elif !defined(CONFIG_PPC64BRIDGE)
+#define CACHE_LINE_SIZE 32
+#define LG_CACHE_LINE_SIZE 5
+#define MAX_COPY_PREFETCH 4
+#else
+#define CACHE_LINE_SIZE 128
+#define LG_CACHE_LINE_SIZE 7
+#define MAX_COPY_PREFETCH 1
+#endif /* CONFIG_4xx || CONFIG_8xx */
+
+ .text
+
+/*
+ * Clear a page using the dcbz instruction, which doesn't cause any
+ * memory traffic (except to write out any cache lines which get
+ * displaced). This only works on cacheable memory.
+ */
+_GLOBAL(clear_page)
+ li r0,4096/CACHE_LINE_SIZE
+ mtctr r0
+#ifdef CONFIG_8xx
+ li r4, 0
+1: stw r4, 0(r3)
+ stw r4, 4(r3)
+ stw r4, 8(r3)
+ stw r4, 12(r3)
+#else
+1: dcbz 0,r3
+#endif
+ addi r3,r3,CACHE_LINE_SIZE
+ bdnz 1b
+ blr
+
+/*
+ * Copy a whole page. We use the dcbz instruction on the destination
+ * to reduce memory traffic (it eliminates the unnecessary reads of
+ * the destination into cache). This requires that the destination
+ * is cacheable.
+ */
+#define COPY_16_BYTES \
+ lwz r6,4(r4); \
+ lwz r7,8(r4); \
+ lwz r8,12(r4); \
+ lwzu r9,16(r4); \
+ stw r6,4(r3); \
+ stw r7,8(r3); \
+ stw r8,12(r3); \
+ stwu r9,16(r3)
+
+_GLOBAL(copy_page)
+ addi r3,r3,-4
+ addi r4,r4,-4
+ li r5,4
+
+#ifndef CONFIG_8xx
+#if MAX_COPY_PREFETCH > 1
+ li r0,MAX_COPY_PREFETCH
+ li r11,4
+ mtctr r0
+11: dcbt r11,r4
+ addi r11,r11,CACHE_LINE_SIZE
+ bdnz 11b
+#else /* MAX_COPY_PREFETCH == 1 */
+ dcbt r5,r4
+ li r11,CACHE_LINE_SIZE+4
+#endif /* MAX_COPY_PREFETCH */
+#endif /* CONFIG_8xx */
+
+ li r0,4096/CACHE_LINE_SIZE
+ mtctr r0
+1:
+#ifndef CONFIG_8xx
+ dcbt r11,r4
+ dcbz r5,r3
+#endif
+ COPY_16_BYTES
+#if CACHE_LINE_SIZE >= 32
+ COPY_16_BYTES
+#if CACHE_LINE_SIZE >= 64
+ COPY_16_BYTES
+ COPY_16_BYTES
+#if CACHE_LINE_SIZE >= 128
+ COPY_16_BYTES
+ COPY_16_BYTES
+ COPY_16_BYTES
+ COPY_16_BYTES
+#endif
+#endif
+#endif
+ bdnz 1b
+ blr
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