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Diffstat (limited to 'arch/mips/lib-64/csum_partial.S')
| -rw-r--r-- | arch/mips/lib-64/csum_partial.S | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/arch/mips/lib-64/csum_partial.S b/arch/mips/lib-64/csum_partial.S new file mode 100644 index 00000000000..25aba660cc9 --- /dev/null +++ b/arch/mips/lib-64/csum_partial.S @@ -0,0 +1,242 @@ +/* + * 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) |