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| author | Philipp Tomsich <philipp.tomsich@theobroma-systems.com> | 2018-11-25 19:22:19 +0100 |
|---|---|---|
| committer | Tom Rini <trini@konsulko.com> | 2018-12-08 20:18:44 -0500 |
| commit | 51c2345bd24837f9f67f16268da6dc71573f1325 (patch) | |
| tree | 318af05398baae25f2ac5ecc8baad6a2e194b365 /lib/crc16.c | |
| parent | a740ee913ec8ba04cc53100440f94841648324e2 (diff) | |
| download | u-boot-51c2345bd24837f9f67f16268da6dc71573f1325.zip u-boot-51c2345bd24837f9f67f16268da6dc71573f1325.tar.gz u-boot-51c2345bd24837f9f67f16268da6dc71573f1325.tar.bz2 | |
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.c | 23 |
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)); +} |