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authorLinus Torvalds <torvalds@linux-foundation.org>2011-07-22 14:43:13 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-07-22 14:43:13 -0700
commit951cc93a7493a81a47e20231441bc6cf17c98a37 (patch)
treef53934f0f225e0215a85c8c59af4c6513e89e3f1 /lib
parenta7e1aabb28e8154ce987b622fd78d80a1ca39361 (diff)
parent415b3334a21aa67806c52d1acf4e72e14f7f402f (diff)
downloadlinux-951cc93a7493a81a47e20231441bc6cf17c98a37.tar.gz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1287 commits)
  icmp: Fix regression in nexthop resolution during replies.
  net: Fix ppc64 BPF JIT dependencies.
  acenic: include NET_SKB_PAD headroom to incoming skbs
  ixgbe: convert to ndo_fix_features
  ixgbe: only enable WoL for magic packet by default
  ixgbe: remove ifdef check for non-existent define
  ixgbe: Pass staterr instead of re-reading status and error bits from descriptor
  ixgbe: Move interrupt related values out of ring and into q_vector
  ixgbe: add structure for containing RX/TX rings to q_vector
  ixgbe: inline the ixgbe_maybe_stop_tx function
  ixgbe: Update ATR to use recorded TX queues instead of CPU for routing
  igb: Fix for DH89xxCC near end loopback test
  e1000: always call e1000_check_for_link() on e1000_ce4100 MACs.
  netxen: add fw version compatibility check
  be2net: request native mode each time the card is reset
  ipv4: Constrain UFO fragment sizes to multiples of 8 bytes
  virtio_net: Fix panic in virtnet_remove
  ipv6: make fragment identifications less predictable
  ipv6: unshare inetpeers
  can: make function can_get_bittiming static
  ...
Diffstat (limited to 'lib')
-rw-r--r--lib/Kconfig14
-rw-r--r--lib/Makefile3
-rw-r--r--lib/checksum.c13
-rw-r--r--lib/cordic.c101
-rw-r--r--lib/crc8.c86
5 files changed, 209 insertions, 8 deletions
diff --git a/lib/Kconfig b/lib/Kconfig
index 830181cc7a83..32f3e5ae2be5 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -79,6 +79,13 @@ config LIBCRC32C
 	  require M here.  See Castagnoli93.
 	  Module will be libcrc32c.
 
+config CRC8
+	tristate "CRC8 function"
+	help
+	  This option provides CRC8 function. Drivers may select this
+	  when they need to do cyclic redundancy check according CRC8
+	  algorithm. Module will be called crc8.
+
 config AUDIT_GENERIC
 	bool
 	depends on AUDIT && !AUDIT_ARCH
@@ -262,4 +269,11 @@ config AVERAGE
 
 	  If unsure, say N.
 
+config CORDIC
+	tristate "Cordic function"
+	help
+	  The option provides arithmetic function using cordic algorithm
+	  so its calculations are in fixed point. Modules can select this
+	  when they require this function. Module will be called cordic.
+
 endmenu
diff --git a/lib/Makefile b/lib/Makefile
index 6b597fdb1898..892f4e282ea1 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -61,6 +61,7 @@ obj-$(CONFIG_CRC_ITU_T)	+= crc-itu-t.o
 obj-$(CONFIG_CRC32)	+= crc32.o
 obj-$(CONFIG_CRC7)	+= crc7.o
 obj-$(CONFIG_LIBCRC32C)	+= libcrc32c.o
+obj-$(CONFIG_CRC8)	+= crc8.o
 obj-$(CONFIG_GENERIC_ALLOCATOR) += genalloc.o
 
 obj-$(CONFIG_ZLIB_INFLATE) += zlib_inflate/
@@ -112,6 +113,8 @@ obj-$(CONFIG_AVERAGE) += average.o
 
 obj-$(CONFIG_CPU_RMAP) += cpu_rmap.o
 
+obj-$(CONFIG_CORDIC) += cordic.o
+
 hostprogs-y	:= gen_crc32table
 clean-files	:= crc32table.h
 
diff --git a/lib/checksum.c b/lib/checksum.c
index 097508732f34..8df2f91e6d98 100644
--- a/lib/checksum.c
+++ b/lib/checksum.c
@@ -49,7 +49,7 @@ static inline unsigned short from32to16(unsigned int x)
 
 static unsigned int do_csum(const unsigned char *buff, int len)
 {
-	int odd, count;
+	int odd;
 	unsigned int result = 0;
 
 	if (len <= 0)
@@ -64,25 +64,22 @@ static unsigned int do_csum(const unsigned char *buff, int len)
 		len--;
 		buff++;
 	}
-	count = len >> 1;		/* nr of 16-bit words.. */
-	if (count) {
+	if (len >= 2) {
 		if (2 & (unsigned long) buff) {
 			result += *(unsigned short *) buff;
-			count--;
 			len -= 2;
 			buff += 2;
 		}
-		count >>= 1;		/* nr of 32-bit words.. */
-		if (count) {
+		if (len >= 4) {
+			const unsigned char *end = buff + ((unsigned)len & ~3);
 			unsigned int carry = 0;
 			do {
 				unsigned int w = *(unsigned int *) buff;
-				count--;
 				buff += 4;
 				result += carry;
 				result += w;
 				carry = (w > result);
-			} while (count);
+			} while (buff < end);
 			result += carry;
 			result = (result & 0xffff) + (result >> 16);
 		}
diff --git a/lib/cordic.c b/lib/cordic.c
new file mode 100644
index 000000000000..aa27a88d7e04
--- /dev/null
+++ b/lib/cordic.c
@@ -0,0 +1,101 @@
+/*
+ * Copyright (c) 2011 Broadcom Corporation
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+#include <linux/module.h>
+#include <linux/cordic.h>
+
+#define CORDIC_ANGLE_GEN	39797
+#define CORDIC_PRECISION_SHIFT	16
+#define	CORDIC_NUM_ITER		(CORDIC_PRECISION_SHIFT + 2)
+
+#define	FIXED(X)	((s32)((X) << CORDIC_PRECISION_SHIFT))
+#define	FLOAT(X)	(((X) >= 0) \
+		? ((((X) >> (CORDIC_PRECISION_SHIFT - 1)) + 1) >> 1) \
+		: -((((-(X)) >> (CORDIC_PRECISION_SHIFT - 1)) + 1) >> 1))
+
+static const s32 arctan_table[] = {
+	2949120,
+	1740967,
+	919879,
+	466945,
+	234379,
+	117304,
+	58666,
+	29335,
+	14668,
+	7334,
+	3667,
+	1833,
+	917,
+	458,
+	229,
+	115,
+	57,
+	29
+};
+
+/*
+ * cordic_calc_iq() - calculates the i/q coordinate for given angle
+ *
+ * theta: angle in degrees for which i/q coordinate is to be calculated
+ * coord: function output parameter holding the i/q coordinate
+ */
+struct cordic_iq cordic_calc_iq(s32 theta)
+{
+	struct cordic_iq coord;
+	s32 angle, valtmp;
+	unsigned iter;
+	int signx = 1;
+	int signtheta;
+
+	coord.i = CORDIC_ANGLE_GEN;
+	coord.q = 0;
+	angle = 0;
+
+	theta = FIXED(theta);
+	signtheta = (theta < 0) ? -1 : 1;
+	theta = ((theta + FIXED(180) * signtheta) % FIXED(360)) -
+		FIXED(180) * signtheta;
+
+	if (FLOAT(theta) > 90) {
+		theta -= FIXED(180);
+		signx = -1;
+	} else if (FLOAT(theta) < -90) {
+		theta += FIXED(180);
+		signx = -1;
+	}
+
+	for (iter = 0; iter < CORDIC_NUM_ITER; iter++) {
+		if (theta > angle) {
+			valtmp = coord.i - (coord.q >> iter);
+			coord.q += (coord.i >> iter);
+			angle += arctan_table[iter];
+		} else {
+			valtmp = coord.i + (coord.q >> iter);
+			coord.q -= (coord.i >> iter);
+			angle -= arctan_table[iter];
+		}
+		coord.i = valtmp;
+	}
+
+	coord.i *= signx;
+	coord.q *= signx;
+	return coord;
+}
+EXPORT_SYMBOL(cordic_calc_iq);
+
+MODULE_DESCRIPTION("Cordic functions");
+MODULE_AUTHOR("Broadcom Corporation");
+MODULE_LICENSE("Dual BSD/GPL");
diff --git a/lib/crc8.c b/lib/crc8.c
new file mode 100644
index 000000000000..87b59cafdb83
--- /dev/null
+++ b/lib/crc8.c
@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2011 Broadcom Corporation
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#define pr_fmt(fmt)		KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/crc8.h>
+#include <linux/printk.h>
+
+/*
+ * crc8_populate_msb - fill crc table for given polynomial in reverse bit order.
+ *
+ * table:	table to be filled.
+ * polynomial:	polynomial for which table is to be filled.
+ */
+void crc8_populate_msb(u8 table[CRC8_TABLE_SIZE], u8 polynomial)
+{
+	int i, j;
+	const u8 msbit = 0x80;
+	u8 t = msbit;
+
+	table[0] = 0;
+
+	for (i = 1; i < CRC8_TABLE_SIZE; i *= 2) {
+		t = (t << 1) ^ (t & msbit ? polynomial : 0);
+		for (j = 0; j < i; j++)
+			table[i+j] = table[j] ^ t;
+	}
+}
+EXPORT_SYMBOL(crc8_populate_msb);
+
+/*
+ * crc8_populate_lsb - fill crc table for given polynomial in regular bit order.
+ *
+ * table:	table to be filled.
+ * polynomial:	polynomial for which table is to be filled.
+ */
+void crc8_populate_lsb(u8 table[CRC8_TABLE_SIZE], u8 polynomial)
+{
+	int i, j;
+	u8 t = 1;
+
+	table[0] = 0;
+
+	for (i = (CRC8_TABLE_SIZE >> 1); i; i >>= 1) {
+		t = (t >> 1) ^ (t & 1 ? polynomial : 0);
+		for (j = 0; j < CRC8_TABLE_SIZE; j += 2*i)
+			table[i+j] = table[j] ^ t;
+	}
+}
+EXPORT_SYMBOL(crc8_populate_lsb);
+
+/*
+ * crc8 - calculate a crc8 over the given input data.
+ *
+ * table: crc table used for calculation.
+ * pdata: pointer to data buffer.
+ * nbytes: number of bytes in data buffer.
+ * crc:	previous returned crc8 value.
+ */
+u8 crc8(const u8 table[CRC8_TABLE_SIZE], u8 *pdata, size_t nbytes, u8 crc)
+{
+	/* loop over the buffer data */
+	while (nbytes-- > 0)
+		crc = table[(crc ^ *pdata++) & 0xff];
+
+	return crc;
+}
+EXPORT_SYMBOL(crc8);
+
+MODULE_DESCRIPTION("CRC8 (by Williams, Ross N.) function");
+MODULE_AUTHOR("Broadcom Corporation");
+MODULE_LICENSE("Dual BSD/GPL");