blackfin architecture

This adds support for the Analog Devices Blackfin processor architecture, and
currently supports the BF533, BF532, BF531, BF537, BF536, BF534, and BF561
(Dual Core) devices, with a variety of development platforms including those
avaliable from Analog Devices (BF533-EZKit, BF533-STAMP, BF537-STAMP,
BF561-EZKIT), and Bluetechnix!  Tinyboards.

The Blackfin architecture was jointly developed by Intel and Analog Devices
Inc.  (ADI) as the Micro Signal Architecture (MSA) core and introduced it in
December of 2000.  Since then ADI has put this core into its Blackfin
processor family of devices.  The Blackfin core has the advantages of a clean,
orthogonal,RISC-like microprocessor instruction set.  It combines a dual-MAC
(Multiply/Accumulate), state-of-the-art signal processing engine and
single-instruction, multiple-data (SIMD) multimedia capabilities into a single
instruction-set architecture.

The Blackfin architecture, including the instruction set, is described by the
ADSP-BF53x/BF56x Blackfin Processor Programming Reference
http://blackfin.uclinux.org/gf/download/frsrelease/29/2549/Blackfin_PRM.pdf

The Blackfin processor is already supported by major releases of gcc, and
there are binary and source rpms/tarballs for many architectures at:
http://blackfin.uclinux.org/gf/project/toolchain/frs There is complete
documentation, including "getting started" guides available at:
http://docs.blackfin.uclinux.org/ which provides links to the sources and
patches you will need in order to set up a cross-compiling environment for
bfin-linux-uclibc

This patch, as well as the other patches (toolchain, distribution,
uClibc) are actively supported by Analog Devices Inc, at:
http://blackfin.uclinux.org/

We have tested this on LTP, and our test plan (including pass/fails) can
be found at:
http://docs.blackfin.uclinux.org/doku.php?id=testing_the_linux_kernel

[m.kozlowski@tuxland.pl: balance parenthesis in blackfin header files]
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
Signed-off-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl>
Signed-off-by: Aubrey Li <aubrey.li@analog.com>
Signed-off-by: Jie Zhang <jie.zhang@analog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 101 insertions, 0 deletions

diff --git a/include/asm-blackfin/checksum.h b/include/asm-blackfin/checksum.h
new file mode 100644
index 000000000000..2638f2586d2f
--- /dev/null
+++ b/include/asm-blackfin/checksum.h
@@ -0,0 +1,101 @@
+#ifndef _BFIN_CHECKSUM_H
+#define _BFIN_CHECKSUM_H
+
+/*
+ * MODIFIED FOR BFIN April 30, 2001 akbar.hussain@lineo.com
+ *
+ * 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 unsigned char *src, unsigned 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
+ */
+
+extern unsigned int csum_partial_copy_from_user(const unsigned char *src,
+                                                unsigned char *dst, int len,
+                                                int sum, int *csum_err);
+
+#define csum_partial_copy_nocheck(src, dst, len, sum)   \
+        csum_partial_copy((src), (dst), (len), (sum))
+
+unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl);
+
+/*
+ *      Fold a partial checksum
+ */
+
+static inline unsigned int csum_fold(unsigned int sum)
+{
+        while (sum >> 16)
+                sum = (sum & 0xffff) + (sum >> 16);
+        return ((~(sum << 16)) >> 16);
+}
+
+/*
+ * computes the checksum of the TCP/UDP pseudo-header
+ * returns a 16-bit checksum, already complemented
+ */
+
+static inline unsigned int
+csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len,
+                   unsigned short proto, unsigned int sum)
+{
+
+        __asm__ ("%0 = %0 + %1;\n\t"
+                 "CC = AC0;\n\t"
+                 "if !CC jump 4;\n\t"
+                 "%0 = %0 + %4;\n\t"
+                 "%0 = %0 + %2;\n\t"
+                 "CC = AC0;\n\t"
+                 "if !CC jump 4;\n\t"
+                 "%0 = %0 + %4;\n\t"
+                 "%0 = %0 + %3;\n\t"
+                 "CC = AC0;\n\t"
+                 "if !CC jump 4;\n\t"
+                 "%0 = %0 + %4;\n\t"
+                 "NOP;\n\t"
+                 : "=d" (sum)
+                 : "d" (daddr), "d" (saddr), "d" ((ntohs(len)<<16)+proto*256), "d" (1), "0"(sum));
+
+        return (sum);
+}
+
+static inline unsigned short int
+csum_tcpudp_magic(unsigned long saddr, unsigned long daddr, unsigned short len,
+                  unsigned short proto, unsigned int 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
+ */
+
+extern unsigned short ip_compute_csum(const unsigned char *buff, int len);
+
+#endif                          /* _BFIN_CHECKSUM_H */