projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| ca15c8ec VG |
1 | /* |
| 2 | * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) | |
| 3 | * | |
| 4 | * This program is free software; you can redistribute it and/or modify | |
| 5 | * it under the terms of the GNU General Public License version 2 as | |
| 6 | * published by the Free Software Foundation. | |
| 7 | * | |
| 8 | * Joern Rennecke <joern.rennecke@embecosm.com>: Jan 2012 | |
| 9 | * -Insn Scheduling improvements to csum core routines. | |
| 10 | * = csum_fold( ) largely derived from ARM version. | |
| 11 | * = ip_fast_cum( ) to have module scheduling | |
| 12 | * -gcc 4.4.x broke networking. Alias analysis needed to be primed. | |
| 13 | * worked around by adding memory clobber to ip_fast_csum( ) | |
| 14 | * | |
| 15 | * vineetg: May 2010 | |
| 16 | * -Rewrote ip_fast_cscum( ) and csum_fold( ) with fast inline asm | |
| 17 | */ | |
| 18 | ||
| 19 | #ifndef _ASM_ARC_CHECKSUM_H | |
| 20 | #define _ASM_ARC_CHECKSUM_H | |
| 21 | ||
| 22 | /* | |
| 23 | * Fold a partial checksum | |
| 24 | * | |
| 25 | * The 2 swords comprising the 32bit sum are added, any carry to 16th bit | |
| 26 | * added back and final sword result inverted. | |
| 27 | */ | |
| 28 | static inline __sum16 csum_fold(__wsum s) | |
| 29 | { | |
| 30 | unsigned r = s << 16 | s >> 16; /* ror */ | |
| 31 | s = ~s; | |
| 32 | s -= r; | |
| 33 | return s >> 16; | |
| 34 | } | |
| 35 | ||
| 36 | /* | |
| 37 | * This is a version of ip_compute_csum() optimized for IP headers, | |
| 38 | * which always checksum on 4 octet boundaries. | |
| 39 | */ | |
| 40 | static inline __sum16 | |
| 41 | ip_fast_csum(const void *iph, unsigned int ihl) | |
| 42 | { | |
| 43 | const void *ptr = iph; | |
| 44 | unsigned int tmp, tmp2, sum; | |
| 45 | ||
| 46 | __asm__( | |
| 47 | " ld.ab %0, [%3, 4] \n" | |
| 48 | " ld.ab %2, [%3, 4] \n" | |
| 49 | " sub %1, %4, 2 \n" | |
| 50 | " lsr.f lp_count, %1, 1 \n" | |
| 51 | " bcc 0f \n" | |
| 52 | " add.f %0, %0, %2 \n" | |
| 53 | " ld.ab %2, [%3, 4] \n" | |
| 54 | "0: lp 1f \n" | |
| 55 | " ld.ab %1, [%3, 4] \n" | |
| 56 | " adc.f %0, %0, %2 \n" | |
| 57 | " ld.ab %2, [%3, 4] \n" | |
| 58 | " adc.f %0, %0, %1 \n" | |
| 59 | "1: adc.f %0, %0, %2 \n" | |
| 60 | " add.cs %0,%0,1 \n" | |
| 61 | : "=&r"(sum), "=r"(tmp), "=&r"(tmp2), "+&r" (ptr) | |
| 62 | : "r"(ihl) | |
| 63 | : "cc", "lp_count", "memory"); | |
| 64 | ||
| 65 | return csum_fold(sum); | |
| 66 | } | |
| 67 | ||
| 68 | /* | |
| 69 | * TCP pseudo Header is 12 bytes: | |
| 70 | * SA [4], DA [4], zeroes [1], Proto[1], TCP Seg(hdr+data) Len [2] | |
| 71 | */ | |
| 72 | static inline __wsum | |
| 01cfbad7 AD |
73 | csum_tcpudp_nofold(__be32 saddr, __be32 daddr, __u32 len, |
| 74 | __u8 proto, __wsum sum) | |
| ca15c8ec VG |
75 | { |
| 76 | __asm__ __volatile__( | |
| 77 | " add.f %0, %0, %1 \n" | |
| 78 | " adc.f %0, %0, %2 \n" | |
| 79 | " adc.f %0, %0, %3 \n" | |
| 80 | " adc.f %0, %0, %4 \n" | |
| 81 | " adc %0, %0, 0 \n" | |
| 82 | : "+&r"(sum) | |
| 83 | : "r"(saddr), "r"(daddr), | |
| 84 | #ifdef CONFIG_CPU_BIG_ENDIAN | |
| 85 | "r"(len), | |
| 86 | #else | |
| 87 | "r"(len << 8), | |
| 88 | #endif | |
| 89 | "r"(htons(proto)) | |
| 90 | : "cc"); | |
| 91 | ||
| 92 | return sum; | |
| 93 | } | |
| 94 | ||
| 95 | #define csum_fold csum_fold | |
| 96 | #define ip_fast_csum ip_fast_csum | |
| 97 | #define csum_tcpudp_nofold csum_tcpudp_nofold | |
| 98 | ||
| 99 | #include <asm-generic/checksum.h> | |
| 100 | ||
| 101 | #endif /* _ASM_ARC_CHECKSUM_H */ |