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>

1 files changed, 11 insertions, 0 deletions

diff --git a/include/u-boot/crc.h b/include/u-boot/crc.h
index 111b22c4b6..788ef29a17 100644
--- a/include/u-boot/crc.h
+++ b/include/u-boot/crc.h
@@ -13,6 +13,17 @@ unsigned int crc8(unsigned int crc_start, const unsigned char *vptr, int len);
 
 /* lib/crc16.c - 16 bit CRC with polynomial x^16+x^12+x^5+1 (CRC-CCITT) */
 uint16_t crc16_ccitt(uint16_t crc_start, const unsigned char *s, int len);
+/**
+ * crc16_ccitt_wd_buf - Perform CRC16-CCIT on an input buffer and return the
+ *                      16-bit result (network byte-order) in an output buffer
+ *
+ * @in:	input buffer
+ * @len: input buffer length
+ * @out: output buffer (at least 2 bytes)
+ * @chunk_sz: ignored
+ */
+void crc16_ccitt_wd_buf(const uint8_t *in, uint len,
+			uint8_t *out, uint chunk_sz);
 
 /* lib/crc32.c */
 uint32_t crc32 (uint32_t, const unsigned char *, uint);