include/asm-sparc64/checksum.h

   1 /* $Id: checksum.h,v 1.13 1999/07/30 09:31:13 davem Exp $ */
   2 #ifndef __SPARC64_CHECKSUM_H
   3 #define __SPARC64_CHECKSUM_H
   4
   5 /*  checksum.h:  IP/UDP/TCP checksum routines on the V9.
   6  *
   7  *  Copyright(C) 1995 Linus Torvalds
   8  *  Copyright(C) 1995 Miguel de Icaza
   9  *  Copyright(C) 1996 David S. Miller
  10  *  Copyright(C) 1996 Eddie C. Dost
  11  *  Copyright(C) 1997 Jakub Jelinek
  12  *
  13  * derived from:
  14  *      Alpha checksum c-code
  15  *      ix86 inline assembly
  16  *      RFC1071 Computing the Internet Checksum
  17  */
  18
  19 #include <asm/uaccess.h>
  20
  21 /* computes the checksum of a memory block at buff, length len,
  22  * and adds in "sum" (32-bit)
  23  *
  24  * returns a 32-bit number suitable for feeding into itself
  25  * or csum_tcpudp_magic
  26  *
  27  * this function must be called with even lengths, except
  28  * for the last fragment, which may be odd
  29  *
  30  * it's best to have buff aligned on a 32-bit boundary
  31  */
  32 extern unsigned int csum_partial(unsigned char * buff, int len, unsigned int sum);
  33
  34 /* the same as csum_partial, but copies from user space while it
  35  * checksums
  36  *
  37  * here even more important to align src and dst on a 32-bit (or even
  38  * better 64-bit) boundary
  39  */
  40 /* FIXME: Remove these macros ASAP */
  41 #define csum_partial_copy(src, dst, len, sum) \
  42                         csum_partial_copy_nocheck(src,dst,len,sum)
  43 #define csum_partial_copy_fromuser(s, d, l, w)  \
  44                         csum_partial_copy_from_user((char *) (s), (d), (l), (w), NULL)
  45
  46 extern unsigned int csum_partial_copy_sparc64(const char *src, char *dst, int len, unsigned int sum);
  47
  48 extern __inline__ unsigned int
  49 csum_partial_copy_nocheck (const char *src, char *dst, int len,
  50                            unsigned int sum)
  51 {
  52         int ret;
  53         unsigned char cur_ds = current->thread.current_ds.seg;
  54         __asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "i" (ASI_P));
  55         ret = csum_partial_copy_sparc64(src, dst, len, sum);
  56         __asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" (cur_ds));
  57         return ret;
  58 }
  59
  60 extern __inline__ unsigned int
  61 csum_partial_copy_from_user(const char *src, char *dst, int len,
  62                             unsigned int sum, int *err)
  63 {
  64         __asm__ __volatile__ ("stx      %0, [%%sp + 0x7ff + 128]"
  65                               : : "r" (err));
  66         return csum_partial_copy_sparc64(src, dst, len, sum);
  67 }
  68
  69 #if 0
  70 /* Not implemented, but nobody uses it yet... */
  71 extern __inline__ unsigned int
  72 csum_partial_copy_to_user(const char *src, char *dst, int len,
  73                           unsigned int sum, int *err)
  74 {
  75         return 0;
  76 }
  77 #endif
  78
  79 /* ihl is always 5 or greater, almost always is 5, and iph is word aligned
  80  * the majority of the time.
  81  */
  82 extern __inline__ unsigned short ip_fast_csum(__const__ unsigned char *iph,
  83                                               unsigned int ihl)
  84 {
  85         unsigned short sum;
  86
  87         /* Note: We must read %2 before we touch %0 for the first time,
  88          *       because GCC can legitimately use the same register for
  89          *       both operands.
  90          */
  91         __asm__ __volatile__("
  92         sub             %2, 4, %%g7             ! IEU0
  93         lduw            [%1 + 0x00], %0         ! Load  Group
  94         lduw            [%1 + 0x04], %%g2       ! Load  Group
  95         lduw            [%1 + 0x08], %%g3       ! Load  Group
  96         addcc           %%g2, %0, %0            ! IEU1  1 Load Bubble + Group
  97         lduw            [%1 + 0x0c], %%g2       ! Load
  98         addccc          %%g3, %0, %0            ! Sngle Group no Bubble
  99         lduw            [%1 + 0x10], %%g3       ! Load  Group
 100         addccc          %%g2, %0, %0            ! Sngle Group no Bubble
 101         addc            %0, %%g0, %0            ! Sngle Group
 102 1:      addcc           %%g3, %0, %0            ! IEU1  Group no Bubble
 103         add             %1, 4, %1               ! IEU0
 104         addccc          %0, %%g0, %0            ! Sngle Group no Bubble
 105         subcc           %%g7, 1, %%g7           ! IEU1  Group
 106         be,a,pt         %%icc, 2f               ! CTI
 107          sll            %0, 16, %%g2            ! IEU0
 108         lduw            [%1 + 0x10], %%g3       ! Load  Group
 109         ba,pt           %%xcc, 1b               ! CTI
 110          nop                                    ! IEU0
 111 2:      addcc           %0, %%g2, %%g2          ! IEU1  Group
 112         srl             %%g2, 16, %0            ! IEU0  Group regdep    XXX Scheisse!
 113         addc            %0, %%g0, %0            ! Sngle Group
 114         xnor            %%g0, %0, %0            ! IEU0  Group
 115         srl             %0, 0, %0               ! IEU0  Group           XXX Scheisse!
 116 "       : "=r" (sum), "=&r" (iph)
 117         : "r" (ihl), "1" (iph)
 118         : "g2", "g3", "g7", "cc");
 119         return sum;
 120 }
 121
 122 /* Fold a partial checksum without adding pseudo headers. */
 123 extern __inline__ unsigned short csum_fold(unsigned int sum)
 124 {
 125         unsigned int tmp;
 126
 127         __asm__ __volatile__("
 128         addcc           %0, %1, %1
 129         srl             %1, 16, %1
 130         addc            %1, %%g0, %1
 131         xnor            %%g0, %1, %0
 132 "       : "=&r" (sum), "=r" (tmp)
 133         : "0" (sum), "1" (sum<<16)
 134         : "cc");
 135         return (sum & 0xffff);
 136 }
 137
 138 extern __inline__ unsigned long csum_tcpudp_nofold(unsigned long saddr,
 139                                                    unsigned long daddr,
 140                                                    unsigned int len,
 141                                                    unsigned short proto,
 142                                                    unsigned int sum)
 143 {
 144         __asm__ __volatile__("
 145         addcc           %1, %0, %0
 146         addccc          %2, %0, %0
 147         addccc          %3, %0, %0
 148         addc            %0, %%g0, %0
 149 "       : "=r" (sum), "=r" (saddr)
 150         : "r" (daddr), "r" ((proto<<16)+len), "0" (sum), "1" (saddr)
 151         : "cc");
 152         return sum;
 153 }
 154
 155 /*
 156  * computes the checksum of the TCP/UDP pseudo-header
 157  * returns a 16-bit checksum, already complemented
 158  */
 159 static inline unsigned short int csum_tcpudp_magic(unsigned long saddr,
 160                                                    unsigned long daddr,
 161                                                    unsigned short len,
 162                                                    unsigned short proto,
 163                                                    unsigned int sum)
 164 {
 165         return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
 166 }
 167
 168 #define _HAVE_ARCH_IPV6_CSUM
 169
 170 static __inline__ unsigned short int csum_ipv6_magic(struct in6_addr *saddr,
 171                                                      struct in6_addr *daddr,
 172                                                      __u16 len,
 173                                                      unsigned short proto,
 174                                                      unsigned int sum)
 175 {
 176         __asm__ __volatile__ ("
 177         addcc           %3, %4, %%g7
 178         addccc          %5, %%g7, %%g7
 179         lduw            [%2 + 0x0c], %%g2
 180         lduw            [%2 + 0x08], %%g3
 181         addccc          %%g2, %%g7, %%g7
 182         lduw            [%2 + 0x04], %%g2
 183         addccc          %%g3, %%g7, %%g7
 184         lduw            [%2 + 0x00], %%g3
 185         addccc          %%g2, %%g7, %%g7
 186         lduw            [%1 + 0x0c], %%g2
 187         addccc          %%g3, %%g7, %%g7
 188         lduw            [%1 + 0x08], %%g3
 189         addccc          %%g2, %%g7, %%g7
 190         lduw            [%1 + 0x04], %%g2
 191         addccc          %%g3, %%g7, %%g7
 192         lduw            [%1 + 0x00], %%g3
 193         addccc          %%g2, %%g7, %%g7
 194         addccc          %%g3, %%g7, %0
 195         addc            0, %0, %0
 196 "       : "=&r" (sum)
 197         : "r" (saddr), "r" (daddr), "r"(htonl((__u32) (len))),
 198           "r"(htonl(proto)), "r"(sum)
 199         : "g2", "g3", "g7", "cc");
 200
 201         return csum_fold(sum);
 202 }
 203
 204 /* this routine is used for miscellaneous IP-like checksums, mainly in icmp.c */
 205 extern __inline__ unsigned short ip_compute_csum(unsigned char * buff, int len)
 206 {
 207         return csum_fold(csum_partial(buff, len, 0));
 208 }
 209
 210 #endif /* !(__SPARC64_CHECKSUM_H) */