diff options
Diffstat (limited to 'arch/parisc/include/asm/checksum.h')
| -rw-r--r-- | arch/parisc/include/asm/checksum.h | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/checksum.h b/arch/parisc/include/asm/checksum.h new file mode 100644 index 000000000..3c43baca7 --- /dev/null +++ b/arch/parisc/include/asm/checksum.h @@ -0,0 +1,177 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _PARISC_CHECKSUM_H +#define _PARISC_CHECKSUM_H + +#include <linux/in6.h> + +/* + * computes the checksum of a memory block at buff, length len, + * and adds in "sum" (32-bit) + * + * returns a 32-bit number suitable for feeding into itself + * or csum_tcpudp_magic + * + * this function must be called with even lengths, except + * for the last fragment, which may be odd + * + * it's best to have buff aligned on a 32-bit boundary + */ +extern __wsum csum_partial(const void *, int, __wsum); + +/* + * Optimized for IP headers, which always checksum on 4 octet boundaries. + * + * Written by Randolph Chung <tausq@debian.org>, and then mucked with by + * LaMont Jones <lamont@debian.org> + */ +static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) +{ + unsigned int sum; + unsigned long t0, t1, t2; + + __asm__ __volatile__ ( +" ldws,ma 4(%1), %0\n" +" addib,<= -4, %2, 2f\n" +"\n" +" ldws 4(%1), %4\n" +" ldws 8(%1), %5\n" +" add %0, %4, %0\n" +" ldws,ma 12(%1), %3\n" +" addc %0, %5, %0\n" +" addc %0, %3, %0\n" +"1: ldws,ma 4(%1), %3\n" +" addib,< 0, %2, 1b\n" +" addc %0, %3, %0\n" +"\n" +" extru %0, 31, 16, %4\n" +" extru %0, 15, 16, %5\n" +" addc %4, %5, %0\n" +" extru %0, 15, 16, %5\n" +" add %0, %5, %0\n" +" subi -1, %0, %0\n" +"2:\n" + : "=r" (sum), "=r" (iph), "=r" (ihl), "=r" (t0), "=r" (t1), "=r" (t2) + : "1" (iph), "2" (ihl) + : "memory"); + + return (__force __sum16)sum; +} + +/* + * Fold a partial checksum + */ +static inline __sum16 csum_fold(__wsum csum) +{ + u32 sum = (__force u32)csum; + /* add the swapped two 16-bit halves of sum, + a possible carry from adding the two 16-bit halves, + will carry from the lower half into the upper half, + giving us the correct sum in the upper half. */ + sum += (sum << 16) + (sum >> 16); + return (__force __sum16)(~sum >> 16); +} + +static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, + __u32 len, __u8 proto, + __wsum sum) +{ + __asm__( + " add %1, %0, %0\n" + " addc %2, %0, %0\n" + " addc %3, %0, %0\n" + " addc %%r0, %0, %0\n" + : "=r" (sum) + : "r" (daddr), "r"(saddr), "r"(proto+len), "0"(sum)); + return sum; +} + +/* + * computes the checksum of the TCP/UDP pseudo-header + * returns a 16-bit checksum, already complemented + */ +static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, + __u32 len, __u8 proto, + __wsum sum) +{ + return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); +} + +/* + * this routine is used for miscellaneous IP-like checksums, mainly + * in icmp.c + */ +static inline __sum16 ip_compute_csum(const void *buf, int len) +{ + return csum_fold (csum_partial(buf, len, 0)); +} + + +#define _HAVE_ARCH_IPV6_CSUM +static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr, + const struct in6_addr *daddr, + __u32 len, __u8 proto, + __wsum sum) +{ + unsigned long t0, t1, t2, t3; + + len += proto; /* add 16-bit proto + len */ + + __asm__ __volatile__ ( + +#if BITS_PER_LONG > 32 + + /* + ** We can execute two loads and two adds per cycle on PA 8000. + ** But add insn's get serialized waiting for the carry bit. + ** Try to keep 4 registers with "live" values ahead of the ALU. + */ + +" ldd,ma 8(%1), %4\n" /* get 1st saddr word */ +" ldd,ma 8(%2), %5\n" /* get 1st daddr word */ +" add %4, %0, %0\n" +" ldd,ma 8(%1), %6\n" /* 2nd saddr */ +" ldd,ma 8(%2), %7\n" /* 2nd daddr */ +" add,dc %5, %0, %0\n" +" add,dc %6, %0, %0\n" +" add,dc %7, %0, %0\n" +" add,dc %3, %0, %0\n" /* fold in proto+len | carry bit */ +" extrd,u %0, 31, 32, %4\n"/* copy upper half down */ +" depdi 0, 31, 32, %0\n"/* clear upper half */ +" add %4, %0, %0\n" /* fold into 32-bits */ +" addc 0, %0, %0\n" /* add carry */ + +#else + + /* + ** For PA 1.x, the insn order doesn't matter as much. + ** Insn stream is serialized on the carry bit here too. + ** result from the previous operation (eg r0 + x) + */ +" ldw,ma 4(%1), %4\n" /* get 1st saddr word */ +" ldw,ma 4(%2), %5\n" /* get 1st daddr word */ +" add %4, %0, %0\n" +" ldw,ma 4(%1), %6\n" /* 2nd saddr */ +" addc %5, %0, %0\n" +" ldw,ma 4(%2), %7\n" /* 2nd daddr */ +" addc %6, %0, %0\n" +" ldw,ma 4(%1), %4\n" /* 3rd saddr */ +" addc %7, %0, %0\n" +" ldw,ma 4(%2), %5\n" /* 3rd daddr */ +" addc %4, %0, %0\n" +" ldw,ma 4(%1), %6\n" /* 4th saddr */ +" addc %5, %0, %0\n" +" ldw,ma 4(%2), %7\n" /* 4th daddr */ +" addc %6, %0, %0\n" +" addc %7, %0, %0\n" +" addc %3, %0, %0\n" /* fold in proto+len, catch carry */ + +#endif + : "=r" (sum), "=r" (saddr), "=r" (daddr), "=r" (len), + "=r" (t0), "=r" (t1), "=r" (t2), "=r" (t3) + : "0" (sum), "1" (saddr), "2" (daddr), "3" (len) + : "memory"); + return csum_fold(sum); +} + +#endif + |