From 51c2345bd24837f9f67f16268da6dc71573f1325 Mon Sep 17 00:00:00 2001 From: Philipp Tomsich Date: Sun, 25 Nov 2018 19:22:19 +0100 Subject: 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 [trini: Fix building crc16.o for SPL/TPL] Signed-off-by: Tom Rini --- lib/Makefile | 1 + lib/crc16.c | 23 +++++++++++++++++------ 2 files changed, 18 insertions(+), 6 deletions(-) (limited to 'lib') diff --git a/lib/Makefile b/lib/Makefile index 8321355a44..a6dd928a92 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -76,6 +76,7 @@ endif ifdef CONFIG_SPL_BUILD obj-$(CONFIG_SPL_YMODEM_SUPPORT) += crc16.o +obj-$(CONFIG_$(SPL_TPL_)HASH_SUPPORT) += crc16.o obj-$(CONFIG_SPL_NET_SUPPORT) += net_utils.o endif obj-$(CONFIG_ADDR_MAP) += addr_map.o diff --git a/lib/crc16.c b/lib/crc16.c index 25bdfd8e72..f46ba727c9 100644 --- a/lib/crc16.c +++ b/lib/crc16.c @@ -22,6 +22,11 @@ *========================================================================== */ +#ifdef USE_HOSTCC +#include +#else +#include +#endif #include /* 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)); +} -- cgit v1.2.3