summaryrefslogtreecommitdiff
path: root/arch/score/include/asm/checksum.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/score/include/asm/checksum.h')
-rw-r--r--arch/score/include/asm/checksum.h235
1 files changed, 235 insertions, 0 deletions
diff --git a/arch/score/include/asm/checksum.h b/arch/score/include/asm/checksum.h
new file mode 100644
index 00000000000..f909ac3144a
--- /dev/null
+++ b/arch/score/include/asm/checksum.h
@@ -0,0 +1,235 @@
+#ifndef _ASM_SCORE_CHECKSUM_H
+#define _ASM_SCORE_CHECKSUM_H
+
+#include <linux/in6.h>
+#include <asm/uaccess.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
+ */
+unsigned int csum_partial(const void *buff, int len, __wsum sum);
+unsigned int csum_partial_copy_from_user(const char *src, char *dst, int len,
+ unsigned int sum, int *csum_err);
+unsigned int csum_partial_copy(const char *src, char *dst,
+ int len, unsigned int sum);
+
+/*
+ * this is a new version of the above that records errors it finds in *errp,
+ * but continues and zeros the rest of the buffer.
+ */
+
+/*
+ * Copy and checksum to user
+ */
+#define HAVE_CSUM_COPY_USER
+static inline
+__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len,
+ __wsum sum, int *err_ptr)
+{
+ sum = csum_partial(src, len, sum);
+ if (copy_to_user(dst, src, len)) {
+ *err_ptr = -EFAULT;
+ return (__force __wsum) -1; /* invalid checksum */
+ }
+ return sum;
+}
+
+
+#define csum_partial_copy_nocheck csum_partial_copy
+/*
+ * Fold a partial checksum without adding pseudo headers
+ */
+
+static inline __sum16 csum_fold(__wsum sum)
+{
+ /* the while loop is unnecessary really, it's always enough with two
+ iterations */
+ __asm__ __volatile__(
+ ".set volatile\n\t"
+ ".set\tr1\n\t"
+ "slli\tr1,%0, 16\n\t"
+ "add\t%0,%0, r1\n\t"
+ "cmp.c\tr1, %0\n\t"
+ "srli\t%0, %0, 16\n\t"
+ "bleu\t1f\n\t"
+ "addi\t%0, 0x1\n\t"
+ "1:ldi\tr30, 0xffff\n\t"
+ "xor\t%0, %0, r30\n\t"
+ "slli\t%0, %0, 16\n\t"
+ "srli\t%0, %0, 16\n\t"
+ ".set\tnor1\n\t"
+ ".set optimize\n\t"
+ : "=r" (sum)
+ : "0" (sum));
+ return 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.
+ */
+static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
+{
+ unsigned int sum;
+ unsigned long dummy;
+
+ __asm__ __volatile__(
+ ".set volatile\n\t"
+ ".set\tnor1\n\t"
+ "lw\t%0, [%1]\n\t"
+ "subri\t%2, %2, 4\n\t"
+ "slli\t%2, %2, 2\n\t"
+ "lw\t%3, [%1, 4]\n\t"
+ "add\t%2, %2, %1\n\t"
+ "add\t%0, %0, %3\n\t"
+ "cmp.c\t%3, %0\n\t"
+ "lw\t%3, [%1, 8]\n\t"
+ "bleu\t1f\n\t"
+ "addi\t%0, 0x1\n\t"
+ "1:\n\t"
+ "add\t%0, %0, %3\n\t"
+ "cmp.c\t%3, %0\n\t"
+ "lw\t%3, [%1, 12]\n\t"
+ "bleu\t1f\n\t"
+ "addi\t%0, 0x1\n\t"
+ "1:add\t%0, %0, %3\n\t"
+ "cmp.c\t%3, %0\n\t"
+ "bleu\t1f\n\t"
+ "addi\t%0, 0x1\n"
+
+ "1:\tlw\t%3, [%1, 16]\n\t"
+ "addi\t%1, 4\n\t"
+ "add\t%0, %0, %3\n\t"
+ "cmp.c\t%3, %0\n\t"
+ "bleu\t2f\n\t"
+ "addi\t%0, 0x1\n"
+ "2:cmp.c\t%2, %1\n\t"
+ "bne\t1b\n\t"
+
+ ".set\tr1\n\t"
+ ".set optimize\n\t"
+ : "=&r" (sum), "=&r" (iph), "=&r" (ihl), "=&r" (dummy)
+ : "1" (iph), "2" (ihl));
+
+ return csum_fold(sum);
+}
+
+static inline __wsum
+csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len,
+ unsigned short proto, __wsum sum)
+{
+ unsigned long tmp = (ntohs(len) << 16) + proto * 256;
+ __asm__ __volatile__(
+ ".set volatile\n\t"
+ "add\t%0, %0, %2\n\t"
+ "cmp.c\t%2, %0\n\t"
+ "bleu\t1f\n\t"
+ "addi\t%0, 0x1\n\t"
+ "1:\n\t"
+ "add\t%0, %0, %3\n\t"
+ "cmp.c\t%3, %0\n\t"
+ "bleu\t1f\n\t"
+ "addi\t%0, 0x1\n\t"
+ "1:\n\t"
+ "add\t%0, %0, %4\n\t"
+ "cmp.c\t%4, %0\n\t"
+ "bleu\t1f\n\t"
+ "addi\t%0, 0x1\n\t"
+ "1:\n\t"
+ ".set optimize\n\t"
+ : "=r" (sum)
+ : "0" (daddr), "r"(saddr),
+ "r" (tmp),
+ "r" (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, unsigned short len,
+ unsigned short 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 unsigned short ip_compute_csum(const void *buff, int len)
+{
+ return csum_fold(csum_partial(buff, 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, unsigned short proto,
+ __wsum sum)
+{
+ __asm__ __volatile__(
+ ".set\tnoreorder\t\t\t# csum_ipv6_magic\n\t"
+ ".set\tnoat\n\t"
+ "addu\t%0, %5\t\t\t# proto (long in network byte order)\n\t"
+ "sltu\t$1, %0, %5\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %6\t\t\t# csum\n\t"
+ "sltu\t$1, %0, %6\n\t"
+ "lw\t%1, 0(%2)\t\t\t# four words source address\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+ "lw\t%1, 4(%2)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+ "lw\t%1, 8(%2)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+ "lw\t%1, 12(%2)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+ "lw\t%1, 0(%3)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+ "lw\t%1, 4(%3)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+ "lw\t%1, 8(%3)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+ "lw\t%1, 12(%3)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+ "addu\t%0, $1\t\t\t# Add final carry\n\t"
+ ".set\tnoat\n\t"
+ ".set\tnoreorder"
+ : "=r" (sum), "=r" (proto)
+ : "r" (saddr), "r" (daddr),
+ "0" (htonl(len)), "1" (htonl(proto)), "r" (sum));
+
+ return csum_fold(sum);
+}
+#endif /* _ASM_SCORE_CHECKSUM_H */