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authorPhilipp Tomsich <philipp.tomsich@theobroma-systems.com>2018-11-25 19:22:19 +0100
committerTom Rini <trini@konsulko.com>2018-12-08 20:18:44 -0500
commit51c2345bd24837f9f67f16268da6dc71573f1325 (patch)
tree318af05398baae25f2ac5ecc8baad6a2e194b365 /lib/crc16.c
parenta740ee913ec8ba04cc53100440f94841648324e2 (diff)
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Roll CRC16-CCITT into the hash infrastructure
The CRC16-CCITT checksum function is useful for space-constrained applications (such as obtaining a checksum across a 2KBit or 4KBit EEPROM) in boot applications. It has not been accessible from boot scripts until now (due to not having a dedicated command and not being supported by the hash infrstructure) limiting its applicability outside of custom commands. This adds the CRC16-CCITT (poly 0x1021, init 0x0) algorithm to the list of available hashes and adds a new crc16_ccitt_wd_buf() to make this possible. Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com> [trini: Fix building crc16.o for SPL/TPL] Signed-off-by: Tom Rini <trini@konsulko.com>
Diffstat (limited to 'lib/crc16.c')
-rw-r--r--lib/crc16.c23
1 files changed, 17 insertions, 6 deletions
diff --git a/lib/crc16.c b/lib/crc16.c
index 25bdfd8..f46ba72 100644
--- a/lib/crc16.c
+++ b/lib/crc16.c
@@ -22,6 +22,11 @@
*==========================================================================
*/
+#ifdef USE_HOSTCC
+#include <arpa/inet.h>
+#else
+#include <common.h>
+#endif
#include <u-boot/crc.h>
/* Table of CRC constants - implements x^16+x^12+x^5+1 */
@@ -60,14 +65,20 @@ static const uint16_t crc16_tab[] = {
0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0,
};
-uint16_t crc16_ccitt(uint16_t crc_start, unsigned char *buf, int len)
+uint16_t crc16_ccitt(uint16_t cksum, const unsigned char *buf, int len)
{
- int i;
- uint16_t cksum;
-
- cksum = crc_start;
- for (i = 0; i < len; i++)
+ for (int i = 0; i < len; i++)
cksum = crc16_tab[((cksum>>8) ^ *buf++) & 0xff] ^ (cksum << 8);
return cksum;
}
+
+void crc16_ccitt_wd_buf(const uint8_t *in, uint len,
+ uint8_t *out, uint chunk_sz)
+{
+ uint16_t crc;
+
+ crc = crc16_ccitt(0, in, len);
+ crc = htons(crc);
+ memcpy(out, &crc, sizeof(crc));
+}