| /* SPDX-License-Identifier: GPL-2.0-only */ |
| /* |
| * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) |
| * |
| * Joern Rennecke <joern.rennecke@embecosm.com>: Jan 2012 |
| * -Insn Scheduling improvements to csum core routines. |
| * = csum_fold( ) largely derived from ARM version. |
| * = ip_fast_cum( ) to have module scheduling |
| * -gcc 4.4.x broke networking. Alias analysis needed to be primed. |
| * worked around by adding memory clobber to ip_fast_csum( ) |
| * |
| * vineetg: May 2010 |
| * -Rewrote ip_fast_cscum( ) and csum_fold( ) with fast inline asm |
| */ |
| |
| #ifndef _ASM_ARC_CHECKSUM_H |
| #define _ASM_ARC_CHECKSUM_H |
| |
| /* |
| * Fold a partial checksum |
| * |
| * The 2 swords comprising the 32bit sum are added, any carry to 16th bit |
| * added back and final sword result inverted. |
| */ |
| static inline __sum16 csum_fold(__wsum s) |
| { |
| unsigned r = s << 16 | s >> 16; /* ror */ |
| s = ~s; |
| s -= r; |
| return s >> 16; |
| } |
| |
| /* |
| * This is a version of ip_compute_csum() optimized for IP headers, |
| * which always checksum on 4 octet boundaries. |
| */ |
| static inline __sum16 |
| ip_fast_csum(const void *iph, unsigned int ihl) |
| { |
| const void *ptr = iph; |
| unsigned int tmp, tmp2, sum; |
| |
| __asm__( |
| " ld.ab %0, [%3, 4] \n" |
| " ld.ab %2, [%3, 4] \n" |
| " sub %1, %4, 2 \n" |
| " lsr.f lp_count, %1, 1 \n" |
| " bcc 0f \n" |
| " add.f %0, %0, %2 \n" |
| " ld.ab %2, [%3, 4] \n" |
| "0: lp 1f \n" |
| " ld.ab %1, [%3, 4] \n" |
| " adc.f %0, %0, %2 \n" |
| " ld.ab %2, [%3, 4] \n" |
| " adc.f %0, %0, %1 \n" |
| "1: adc.f %0, %0, %2 \n" |
| " add.cs %0,%0,1 \n" |
| : "=&r"(sum), "=r"(tmp), "=&r"(tmp2), "+&r" (ptr) |
| : "r"(ihl) |
| : "cc", "lp_count", "memory"); |
| |
| return csum_fold(sum); |
| } |
| |
| /* |
| * TCP pseudo Header is 12 bytes: |
| * SA [4], DA [4], zeroes [1], Proto[1], TCP Seg(hdr+data) Len [2] |
| */ |
| static inline __wsum |
| csum_tcpudp_nofold(__be32 saddr, __be32 daddr, __u32 len, |
| __u8 proto, __wsum sum) |
| { |
| __asm__ __volatile__( |
| " add.f %0, %0, %1 \n" |
| " adc.f %0, %0, %2 \n" |
| " adc.f %0, %0, %3 \n" |
| " adc.f %0, %0, %4 \n" |
| " adc %0, %0, 0 \n" |
| : "+&r"(sum) |
| : "r"(saddr), "r"(daddr), |
| #ifdef CONFIG_CPU_BIG_ENDIAN |
| "r"(len), |
| #else |
| "r"(len << 8), |
| #endif |
| "r"(htons(proto)) |
| : "cc"); |
| |
| return sum; |
| } |
| |
| #define csum_fold csum_fold |
| #define ip_fast_csum ip_fast_csum |
| #define csum_tcpudp_nofold csum_tcpudp_nofold |
| |
| #include <asm-generic/checksum.h> |
| |
| #endif /* _ASM_ARC_CHECKSUM_H */ |
