| /* |
| * 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) |
