diff options
Diffstat (limited to 'arch/avr32/lib/csum_partial.S')
| -rw-r--r-- | arch/avr32/lib/csum_partial.S | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/arch/avr32/lib/csum_partial.S b/arch/avr32/lib/csum_partial.S new file mode 100644 index 0000000..6a262b5 --- /dev/null +++ b/arch/avr32/lib/csum_partial.S @@ -0,0 +1,47 @@ +/* + * Copyright (C) 2004-2006 Atmel Corporation + * + * 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. + */ + + /* + * unsigned int csum_partial(const unsigned char *buff, + * int len, unsigned int sum) + */ + .text + .global csum_partial + .type csum_partial,"function" + .align 1 +csum_partial: + /* checksum complete words, aligned or not */ +3: sub r11, 4 + brlt 5f +4: ld.w r9, r12++ + add r10, r9 + acr r10 + sub r11, 4 + brge 4b + + /* return if we had a whole number of words */ +5: sub r11, -4 + reteq r10 + + /* checksum any remaining bytes at the end */ + mov r9, 0 + mov r8, 0 + cp r11, 2 + brlt 6f + ld.uh r9, r12++ + sub r11, 2 + breq 7f + lsl r9, 16 +6: ld.ub r8, r12++ + lsl r8, 8 +7: or r9, r8 + add r10, r9 + acr r10 + + retal r10 + .size csum_partial, . - csum_partial |