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-rw-r--r--arch/parisc/include/asm/checksum.h177
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
+