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Diffstat (limited to 'arch/mips/lib/csum_partial.S')
| -rw-r--r-- | arch/mips/lib/csum_partial.S | 273 |
1 files changed, 273 insertions, 0 deletions
diff --git a/arch/mips/lib/csum_partial.S b/arch/mips/lib/csum_partial.S new file mode 100644 index 00000000000..9db357294be --- /dev/null +++ b/arch/mips/lib/csum_partial.S @@ -0,0 +1,273 @@ +/* + * 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> + +#ifdef CONFIG_64BIT +/* + * As we are sharing code base with the mips32 tree (which use the o32 ABI + * register definitions). We need to redefine the register definitions from + * the n64 ABI register naming to the o32 ABI register naming. + */ +#undef t0 +#undef t1 +#undef t2 +#undef t3 +#define t0 $8 +#define t1 $9 +#define t2 $10 +#define t3 $11 +#define t4 $12 +#define t5 $13 +#define t6 $14 +#define t7 $15 + +#define USE_DOUBLE +#endif + +#ifdef USE_DOUBLE + +#define LOAD ld +#define ADD daddu +#define NBYTES 8 + +#else + +#define LOAD lw +#define ADD addu +#define NBYTES 4 + +#endif /* USE_DOUBLE */ + +#define UNIT(unit) ((unit)*NBYTES) + +#define ADDC(sum,reg) \ + ADD sum, reg; \ + sltu v1, sum, reg; \ + ADD sum, v1 + +#define CSUM_BIGCHUNK1(src, offset, sum, _t0, _t1, _t2, _t3) \ + LOAD _t0, (offset + UNIT(0))(src); \ + LOAD _t1, (offset + UNIT(1))(src); \ + LOAD _t2, (offset + UNIT(2))(src); \ + LOAD _t3, (offset + UNIT(3))(src); \ + ADDC(sum, _t0); \ + ADDC(sum, _t1); \ + ADDC(sum, _t2); \ + ADDC(sum, _t3) + +#ifdef USE_DOUBLE +#define CSUM_BIGCHUNK(src, offset, sum, _t0, _t1, _t2, _t3) \ + CSUM_BIGCHUNK1(src, offset, sum, _t0, _t1, _t2, _t3) +#else +#define CSUM_BIGCHUNK(src, offset, sum, _t0, _t1, _t2, _t3) \ + CSUM_BIGCHUNK1(src, offset, sum, _t0, _t1, _t2, _t3); \ + CSUM_BIGCHUNK1(src, offset + 0x10, sum, _t0, _t1, _t2, _t3) +#endif + +/* + * a0: source address + * a1: length of the area to checksum + * a2: partial checksum + */ + +#define src a0 +#define sum v0 + + .text + .set noreorder + .align 5 +LEAF(csum_partial) + move sum, zero + move t7, zero + + sltiu t8, a1, 0x8 + bnez t8, small_csumcpy /* < 8 bytes to copy */ + move t2, a1 + + andi t7, src, 0x1 /* odd buffer? */ + +hword_align: + beqz t7, word_align + andi t8, src, 0x2 + + lbu t0, (src) + LONG_SUBU a1, a1, 0x1 +#ifdef __MIPSEL__ + sll t0, t0, 8 +#endif + ADDC(sum, t0) + PTR_ADDU src, src, 0x1 + andi t8, src, 0x2 + +word_align: + beqz t8, dword_align + sltiu t8, a1, 56 + + lhu t0, (src) + LONG_SUBU a1, a1, 0x2 + ADDC(sum, t0) + sltiu t8, a1, 56 + PTR_ADDU 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 t0, 0x00(src) + LONG_SUBU a1, a1, 0x4 + ADDC(sum, t0) + PTR_ADDU src, src, 0x4 + andi t8, src, 0x8 + +qword_align: + beqz t8, oword_align + andi t8, src, 0x10 + +#ifdef USE_DOUBLE + ld t0, 0x00(src) + LONG_SUBU a1, a1, 0x8 + ADDC(sum, t0) +#else + lw t0, 0x00(src) + lw t1, 0x04(src) + LONG_SUBU a1, a1, 0x8 + ADDC(sum, t0) + ADDC(sum, t1) +#endif + PTR_ADDU src, src, 0x8 + andi t8, src, 0x10 + +oword_align: + beqz t8, begin_movement + LONG_SRL t8, a1, 0x7 + +#ifdef USE_DOUBLE + ld t0, 0x00(src) + ld t1, 0x08(src) + ADDC(sum, t0) + ADDC(sum, t1) +#else + CSUM_BIGCHUNK1(src, 0x00, sum, t0, t1, t3, t4) +#endif + LONG_SUBU a1, a1, 0x10 + PTR_ADDU src, src, 0x10 + LONG_SRL t8, a1, 0x7 + +begin_movement: + beqz t8, 1f + andi t2, a1, 0x40 + +move_128bytes: + CSUM_BIGCHUNK(src, 0x00, sum, t0, t1, t3, t4) + CSUM_BIGCHUNK(src, 0x20, sum, t0, t1, t3, t4) + CSUM_BIGCHUNK(src, 0x40, sum, t0, t1, t3, t4) + CSUM_BIGCHUNK(src, 0x60, sum, t0, t1, t3, t4) + LONG_SUBU t8, t8, 0x01 + bnez t8, move_128bytes + PTR_ADDU src, src, 0x80 + +1: + beqz t2, 1f + andi t2, a1, 0x20 + +move_64bytes: + CSUM_BIGCHUNK(src, 0x00, sum, t0, t1, t3, t4) + CSUM_BIGCHUNK(src, 0x20, sum, t0, t1, t3, t4) + PTR_ADDU src, src, 0x40 + +1: + beqz t2, do_end_words + andi t8, a1, 0x1c + +move_32bytes: + CSUM_BIGCHUNK(src, 0x00, sum, t0, t1, t3, t4) + andi t8, a1, 0x1c + PTR_ADDU src, src, 0x20 + +do_end_words: + beqz t8, small_csumcpy + andi t2, a1, 0x3 + LONG_SRL t8, t8, 0x2 + +end_words: + lw t0, (src) + LONG_SUBU t8, t8, 0x1 + ADDC(sum, t0) + bnez t8, end_words + PTR_ADDU src, src, 0x4 + +/* unknown src alignment and < 8 bytes to go */ +small_csumcpy: + move a1, t2 + + andi t0, a1, 4 + beqz t0, 1f + andi t0, a1, 2 + + /* Still a full word to go */ + ulw t1, (src) + PTR_ADDIU src, 4 + ADDC(sum, t1) + +1: move t1, zero + beqz t0, 1f + andi t0, a1, 1 + + /* Still a halfword to go */ + ulhu t1, (src) + PTR_ADDIU src, 2 + +1: beqz t0, 1f + sll t1, t1, 16 + + lbu t2, (src) + nop + +#ifdef __MIPSEB__ + sll t2, t2, 8 +#endif + or t1, t2 + +1: ADDC(sum, t1) + + /* fold checksum */ +#ifdef USE_DOUBLE + dsll32 v1, sum, 0 + daddu sum, v1 + sltu v1, sum, v1 + dsra32 sum, sum, 0 + addu sum, v1 +#endif + sll v1, sum, 16 + addu sum, v1 + sltu v1, sum, v1 + srl sum, sum, 16 + addu sum, v1 + + /* odd buffer alignment? */ + beqz t7, 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 + END(csum_partial) |