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#ifndef __ASM_ARM_CHECKSUM_H

#define __ASM_ARM_CHECKSUM_H

#ifndef __ASM_ARM_SEGMENT_H

#include <asm/segment.h>

#endif

/*

 * 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

 */

unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum);

/*

 * the same as csum_partial, but copies from src while it

 * checksums

 *

 * here even more important to align src and dst on a 32-bit (or even

 * better 64-bit) boundary

 */

unsigned int csum_partial_copy( const char *src, char *dst, int len, int sum);

/*

 * the same as csum_partial_copy, but copies from user space.

 *

 * here even more important to align src and dst on a 32-bit (or even

 * better 64-bit) boundary

 */

static __INLINE__ unsigned int csum_partial_copy_fromuser(const char *src, char *dst, int len, int sum)

{

        extern unsigned int __csum_partial_copy_fromuser(const char *src, char *dst, int len, int sum);

        if (IS_USER_SEG)

                return __csum_partial_copy_fromuser (src, dst, len, sum);

        else

                return csum_partial_copy (src, dst, len, sum);

}

/*

 *      This is a version of ip_compute_csum() optimized for IP headers,

 *      which always checksum on 4 octet boundaries.

 *

 *      By Jorge Cwik <jorge@laser.satlink.net>, adapted for linux by

 *      Arnt Gulbrandsen.

 *

 *      Converted to ARM by R.M.King

 */

static inline unsigned short ip_fast_csum(unsigned char * iph,

                                          unsigned int ihl) {

        unsigned int sum, tmp1;

    __asm__ __volatile__("

        sub     %2, %2, #5

        ldr     %0, [%1], #4

        ldr     %3, [%1], #4

        adds    %0, %0, %3

        ldr     %3, [%1], #4

        adcs    %0, %0, %3

        ldr     %3, [%1], #4

        adcs    %0, %0, %3

1:      ldr     %3, [%1], #4

        adcs    %0, %0, %3

        tst     %2, #15

        subne   %2, %2, #1

        bne     1b

        adc     %0, %0, #0

        adds    %0, %0, %0, lsl #16

        addcs   %0, %0, #0x10000

        mvn     %0, %0

        mov     %0, %0, lsr #16

         "

        : "=&r" (sum), "=&r" (iph), "=&r" (ihl), "=&r" (tmp1)

        : "1" (iph), "2" (ihl));

        return(sum);

}

/*

 * computes the checksum of the TCP/UDP pseudo-header

 * returns a 16-bit checksum, already complemented

 */

static inline unsigned short int csum_tcpudp_magic(unsigned long saddr,

                                                   unsigned long daddr,

                                                   unsigned short len,

                                                   unsigned short proto,

                                                   unsigned int sum) {

    __asm__ __volatile__("

    adds        %0, %0, %1

    adcs        %0, %0, %4

    adcs        %0, %0, %5

    adc         %0, %0, #0

    adds        %0, %0, %0, lsl #16

    addcs       %0, %0, #0x10000

    mvn         %0, %0

    mov         %0, %0, lsr #16

        "

        : "=&r" (sum), "=&r" (saddr)

        : "0" (daddr), "1"(saddr), "r"((ntohs(len)<<16)+proto*256), "r"(sum));

        return((unsigned short)sum);

}

/*

 *      Fold a partial checksum without adding pseudo headers

 */

static inline unsigned int csum_fold(unsigned int sum)

{

    __asm__ __volatile__("

    adds        %0, %0, %0, lsl #16

    addcss      %0, %0, #0x10000

    addcs       %0, %0, #0x10000

    mvn         %0, %0

    mov         %0, %0, lsr #16

        "

        : "=r" (sum)

        : "0" (sum));

        return sum;

}

/*

 * this routine is used for miscellaneous IP-like checksums, mainly

 * in icmp.c

 */

static inline unsigned short ip_compute_csum(unsigned char * buff, int len) {

    unsigned int sum;

    __asm__ __volatile__("

    adds        %0, %0, %0, lsl #16

    addcs       %0, %0, #0x10000

    mvn         %0, %0

    mov         %0, %0, lsr #16

        "

        : "=r"(sum)

        : "0" (csum_partial(buff, len, 0)));

        return(sum);

}

#endif