Hi Peter,
On Fri, 30 Aug 2024 at 06:17, Peter Robinson pbrobinson@gmail.com wrote:
On Thu, 29 Aug 2024 at 16:02, Simon Glass sjg@chromium.org wrote:
Add an entry for crc8, with watchdog handling.
What's the watchdog handling do? What's this used for?
It does the hashing in chunks and touches the watchdog after every chunk, to avoid the board resetting.
Looking at the use of crc8 it's minimally used.
Yes, it's a cheap algorithm which provides some protection, so I am using it in the VBE relocating loader (to come).
Signed-off-by: Simon Glass sjg@chromium.org
common/hash.c | 8 ++++++++ include/u-boot/crc.h | 3 +++ lib/crc8.c | 6 ++++++ 3 files changed, 17 insertions(+)
diff --git a/common/hash.c b/common/hash.c index ac63803fed9..43c4e185750 100644 --- a/common/hash.c +++ b/common/hash.c @@ -304,6 +304,14 @@ static struct hash_algo hash_algo[] = { .hash_update = hash_update_crc16_ccitt, .hash_finish = hash_finish_crc16_ccitt, }, +#if CONFIG_IS_ENABLED(CRC8)
{.name = "crc8",.digest_size = 1,.chunk_size = CHUNKSZ_CRC32,.hash_func_ws = crc8_wd_buf,},+#endif #if CONFIG_IS_ENABLED(CRC32) { .name = "crc32", diff --git a/include/u-boot/crc.h b/include/u-boot/crc.h index 5174bd7ac41..b2badaf6a97 100644 --- a/include/u-boot/crc.h +++ b/include/u-boot/crc.h @@ -25,6 +25,9 @@ */ unsigned int crc8(unsigned int crc_start, const unsigned char *vptr, int len);
+void crc8_wd_buf(const unsigned char *input, unsigned int len,
unsigned char output[1], unsigned int chunk_sz);/* lib/crc16.c - 16 bit CRC with polynomial x^16 + x^15 + x^2 + 1 */ uint16_t crc16(uint16_t crc, const unsigned char *buffer, size_t len);
diff --git a/lib/crc8.c b/lib/crc8.c index 20d46d16147..811e19917b4 100644 --- a/lib/crc8.c +++ b/lib/crc8.c @@ -32,3 +32,9 @@ unsigned int crc8(unsigned int crc, const unsigned char *vptr, int len)
return crc;}
+void crc8_wd_buf(const unsigned char *input, unsigned int len,
unsigned char output[1], unsigned int chunk_sz)+{
*output = crc8(0, input, len);+}
2.34.1
Regards, Simon