| Mikael Starvik | 51533b6 | 2005-07-27 11:44:44 -0700 | [diff] [blame] | 1 | #ifndef _ASM_CRIS_ARCH_CHECKSUM_H |
| 2 | #define _ASM_CRIS_ARCH_CHECKSUM_H |
| 3 | |
| 4 | /* |
| 5 | * Check values used in TCP/UDP headers. |
| 6 | * |
| 7 | * The gain of doing this in assembler instead of C, is that C doesn't |
| 8 | * generate carry-additions for the 32-bit components of the |
| 9 | * checksum. Which means it would be necessary to split all those into |
| 10 | * 16-bit components and then add. |
| 11 | */ |
| Adrian Bunk | d9b5444 | 2005-11-07 00:58:44 -0800 | [diff] [blame] | 12 | static inline unsigned int |
| Mikael Starvik | 51533b6 | 2005-07-27 11:44:44 -0700 | [diff] [blame] | 13 | csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, |
| 14 | unsigned short len, unsigned short proto, unsigned int sum) |
| 15 | { |
| 16 | int res; |
| 17 | |
| 18 | __asm__ __volatile__ ("add.d %2, %0\n\t" |
| 19 | "addc %3, %0\n\t" |
| 20 | "addc %4, %0\n\t" |
| 21 | "addc 0, %0\n\t" |
| 22 | : "=r" (res) |
| 23 | : "0" (sum), "r" (daddr), "r" (saddr), \ |
| 24 | "r" ((ntohs(len) << 16) + (proto << 8))); |
| 25 | |
| 26 | return res; |
| 27 | } |
| 28 | |
| 29 | #endif /* _ASM_CRIS_ARCH_CHECKSUM_H */ |