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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/arc/lib/memset-archs.S
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arc/lib/memset-archs.S')
-rw-r--r--arch/arc/lib/memset-archs.S146
1 files changed, 146 insertions, 0 deletions
diff --git a/arch/arc/lib/memset-archs.S b/arch/arc/lib/memset-archs.S
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+++ b/arch/arc/lib/memset-archs.S
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+/*
+ * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/linkage.h>
+#include <asm/cache.h>
+
+/*
+ * The memset implementation below is optimized to use prefetchw and prealloc
+ * instruction in case of CPU with 64B L1 data cache line (L1_CACHE_SHIFT == 6)
+ * If you want to implement optimized memset for other possible L1 data cache
+ * line lengths (32B and 128B) you should rewrite code carefully checking
+ * we don't call any prefetchw/prealloc instruction for L1 cache lines which
+ * don't belongs to memset area.
+ */
+
+#if L1_CACHE_SHIFT == 6
+
+.macro PREALLOC_INSTR reg, off
+ prealloc [\reg, \off]
+.endm
+
+.macro PREFETCHW_INSTR reg, off
+ prefetchw [\reg, \off]
+.endm
+
+#else
+
+.macro PREALLOC_INSTR
+.endm
+
+.macro PREFETCHW_INSTR
+.endm
+
+#endif
+
+ENTRY_CFI(memset)
+ PREFETCHW_INSTR r0, 0 ; Prefetch the first write location
+ mov.f 0, r2
+;;; if size is zero
+ jz.d [blink]
+ mov r3, r0 ; don't clobber ret val
+
+;;; if length < 8
+ brls.d.nt r2, 8, .Lsmallchunk
+ mov.f lp_count,r2
+
+ and.f r4, r0, 0x03
+ rsub lp_count, r4, 4
+ lpnz @.Laligndestination
+ ;; LOOP BEGIN
+ stb.ab r1, [r3,1]
+ sub r2, r2, 1
+.Laligndestination:
+
+;;; Destination is aligned
+ and r1, r1, 0xFF
+ asl r4, r1, 8
+ or r4, r4, r1
+ asl r5, r4, 16
+ or r5, r5, r4
+ mov r4, r5
+
+ sub3 lp_count, r2, 8
+ cmp r2, 64
+ bmsk.hi r2, r2, 5
+ mov.ls lp_count, 0
+ add3.hi r2, r2, 8
+
+;;; Convert len to Dwords, unfold x8
+ lsr.f lp_count, lp_count, 6
+
+ lpnz @.Lset64bytes
+ ;; LOOP START
+ PREALLOC_INSTR r3, 64 ; alloc next line w/o fetching
+
+#ifdef CONFIG_ARC_HAS_LL64
+ std.ab r4, [r3, 8]
+ std.ab r4, [r3, 8]
+ std.ab r4, [r3, 8]
+ std.ab r4, [r3, 8]
+ std.ab r4, [r3, 8]
+ std.ab r4, [r3, 8]
+ std.ab r4, [r3, 8]
+ std.ab r4, [r3, 8]
+#else
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+#endif
+.Lset64bytes:
+
+ lsr.f lp_count, r2, 5 ;Last remaining max 124 bytes
+ lpnz .Lset32bytes
+ ;; LOOP START
+#ifdef CONFIG_ARC_HAS_LL64
+ std.ab r4, [r3, 8]
+ std.ab r4, [r3, 8]
+ std.ab r4, [r3, 8]
+ std.ab r4, [r3, 8]
+#else
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+ st.ab r4, [r3, 4]
+#endif
+.Lset32bytes:
+
+ and.f lp_count, r2, 0x1F ;Last remaining 31 bytes
+.Lsmallchunk:
+ lpnz .Lcopy3bytes
+ ;; LOOP START
+ stb.ab r1, [r3, 1]
+.Lcopy3bytes:
+
+ j [blink]
+
+END_CFI(memset)
+
+ENTRY_CFI(memzero)
+ ; adjust bzero args to memset args
+ mov r2, r1
+ b.d memset ;tail call so need to tinker with blink
+ mov r1, 0
+END_CFI(memzero)