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-rw-r--r--arch/mips/lib-64/csum_partial.S242
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diff --git a/arch/mips/lib-64/csum_partial.S b/arch/mips/lib-64/csum_partial.S
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+++ b/arch/mips/lib-64/csum_partial.S
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+/*
+ * 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.
+ *
+ * Quick'n'dirty IP checksum ...
+ *
+ * Copyright (C) 1998, 1999 Ralf Baechle
+ * Copyright (C) 1999 Silicon Graphics, Inc.
+ */
+#include <asm/asm.h>
+#include <asm/regdef.h>
+
+#define ADDC(sum,reg) \
+ addu sum, reg; \
+ sltu v1, sum, reg; \
+ addu sum, v1
+
+#define CSUM_BIGCHUNK(src, offset, sum, t0, t1, t2, t3) \
+ lw t0, (offset + 0x00)(src); \
+ lw t1, (offset + 0x04)(src); \
+ lw t2, (offset + 0x08)(src); \
+ lw t3, (offset + 0x0c)(src); \
+ ADDC(sum, t0); \
+ ADDC(sum, t1); \
+ ADDC(sum, t2); \
+ ADDC(sum, t3); \
+ lw t0, (offset + 0x10)(src); \
+ lw t1, (offset + 0x14)(src); \
+ lw t2, (offset + 0x18)(src); \
+ lw t3, (offset + 0x1c)(src); \
+ ADDC(sum, t0); \
+ ADDC(sum, t1); \
+ ADDC(sum, t2); \
+ ADDC(sum, t3); \
+
+/*
+ * a0: source address
+ * a1: length of the area to checksum
+ * a2: partial checksum
+ */
+
+#define src a0
+#define sum v0
+
+ .text
+ .set noreorder
+
+/* unknown src alignment and < 8 bytes to go */
+small_csumcpy:
+ move a1, ta2
+
+ andi ta0, a1, 4
+ beqz ta0, 1f
+ andi ta0, a1, 2
+
+ /* Still a full word to go */
+ ulw ta1, (src)
+ daddiu src, 4
+ ADDC(sum, ta1)
+
+1: move ta1, zero
+ beqz ta0, 1f
+ andi ta0, a1, 1
+
+ /* Still a halfword to go */
+ ulhu ta1, (src)
+ daddiu src, 2
+
+1: beqz ta0, 1f
+ sll ta1, ta1, 16
+
+ lbu ta2, (src)
+ nop
+
+#ifdef __MIPSEB__
+ sll ta2, ta2, 8
+#endif
+ or ta1, ta2
+
+1: ADDC(sum, ta1)
+
+ /* fold checksum */
+ sll v1, sum, 16
+ addu sum, v1
+ sltu v1, sum, v1
+ srl sum, sum, 16
+ addu sum, v1
+
+ /* odd buffer alignment? */
+ beqz t3, 1f
+ nop
+ sll v1, sum, 8
+ srl sum, sum, 8
+ or sum, v1
+ andi sum, 0xffff
+1:
+ .set reorder
+ /* Add the passed partial csum. */
+ ADDC(sum, a2)
+ jr ra
+ .set noreorder
+
+/* ------------------------------------------------------------------------- */
+
+ .align 5
+LEAF(csum_partial)
+ move sum, zero
+ move t3, zero
+
+ sltiu t8, a1, 0x8
+ bnez t8, small_csumcpy /* < 8 bytes to copy */
+ move ta2, a1
+
+ beqz a1, out
+ andi t3, src, 0x1 /* odd buffer? */
+
+hword_align:
+ beqz t3, word_align
+ andi t8, src, 0x2
+
+ lbu ta0, (src)
+ dsubu a1, a1, 0x1
+#ifdef __MIPSEL__
+ sll ta0, ta0, 8
+#endif
+ ADDC(sum, ta0)
+ daddu src, src, 0x1
+ andi t8, src, 0x2
+
+word_align:
+ beqz t8, dword_align
+ sltiu t8, a1, 56
+
+ lhu ta0, (src)
+ dsubu a1, a1, 0x2
+ ADDC(sum, ta0)
+ sltiu t8, a1, 56
+ daddu src, src, 0x2
+
+dword_align:
+ bnez t8, do_end_words
+ move t8, a1
+
+ andi t8, src, 0x4
+ beqz t8, qword_align
+ andi t8, src, 0x8
+
+ lw ta0, 0x00(src)
+ dsubu a1, a1, 0x4
+ ADDC(sum, ta0)
+ daddu src, src, 0x4
+ andi t8, src, 0x8
+
+qword_align:
+ beqz t8, oword_align
+ andi t8, src, 0x10
+
+ lw ta0, 0x00(src)
+ lw ta1, 0x04(src)
+ dsubu a1, a1, 0x8
+ ADDC(sum, ta0)
+ ADDC(sum, ta1)
+ daddu src, src, 0x8
+ andi t8, src, 0x10
+
+oword_align:
+ beqz t8, begin_movement
+ dsrl t8, a1, 0x7
+
+ lw ta3, 0x08(src)
+ lw t0, 0x0c(src)
+ lw ta0, 0x00(src)
+ lw ta1, 0x04(src)
+ ADDC(sum, ta3)
+ ADDC(sum, t0)
+ ADDC(sum, ta0)
+ ADDC(sum, ta1)
+ dsubu a1, a1, 0x10
+ daddu src, src, 0x10
+ dsrl t8, a1, 0x7
+
+begin_movement:
+ beqz t8, 1f
+ andi ta2, a1, 0x40
+
+move_128bytes:
+ CSUM_BIGCHUNK(src, 0x00, sum, ta0, ta1, ta3, t0)
+ CSUM_BIGCHUNK(src, 0x20, sum, ta0, ta1, ta3, t0)
+ CSUM_BIGCHUNK(src, 0x40, sum, ta0, ta1, ta3, t0)
+ CSUM_BIGCHUNK(src, 0x60, sum, ta0, ta1, ta3, t0)
+ dsubu t8, t8, 0x01
+ bnez t8, move_128bytes
+ daddu src, src, 0x80
+
+1:
+ beqz ta2, 1f
+ andi ta2, a1, 0x20
+
+move_64bytes:
+ CSUM_BIGCHUNK(src, 0x00, sum, ta0, ta1, ta3, t0)
+ CSUM_BIGCHUNK(src, 0x20, sum, ta0, ta1, ta3, t0)
+ daddu src, src, 0x40
+
+1:
+ beqz ta2, do_end_words
+ andi t8, a1, 0x1c
+
+move_32bytes:
+ CSUM_BIGCHUNK(src, 0x00, sum, ta0, ta1, ta3, t0)
+ andi t8, a1, 0x1c
+ daddu src, src, 0x20
+
+do_end_words:
+ beqz t8, maybe_end_cruft
+ dsrl t8, t8, 0x2
+
+end_words:
+ lw ta0, (src)
+ dsubu t8, t8, 0x1
+ ADDC(sum, ta0)
+ bnez t8, end_words
+ daddu src, src, 0x4
+
+maybe_end_cruft:
+ andi ta2, a1, 0x3
+
+small_memcpy:
+ j small_csumcpy; move a1, ta2 /* XXX ??? */
+ beqz t2, out
+ move a1, ta2
+
+end_bytes:
+ lb ta0, (src)
+ dsubu a1, a1, 0x1
+ bnez a2, end_bytes
+ daddu src, src, 0x1
+
+out:
+ jr ra
+ move v0, sum
+ END(csum_partial)