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authorPatrick Rudolph <siro@das-labor.org>2019-12-15 18:03:36 +0100
committerPatrick Rudolph <siro@das-labor.org>2020-01-07 08:38:58 +0000
commitcc0b6f18cdcce54a92961573b653e5f947d40651 (patch)
tree8128870a1d9b921ea1885ef7ec08dfdcbcb7b5a5 /src
parent389c8279432a4e213391ed21ef25707090fde7ef (diff)
lib/crc_byte: Add CRC32 implementation
* Add CRC32 using polynomial 0x04C11DB7 + Add macro to caculate CRC of a buffer Change-Id: If98e4e12bb53a6e5123e94e8cdffde1eb3bc4b4b Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/37753 Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Diffstat (limited to 'src')
-rw-r--r--src/include/crc_byte.h19
-rw-r--r--src/lib/crc_byte.c14
2 files changed, 33 insertions, 0 deletions
diff --git a/src/include/crc_byte.h b/src/include/crc_byte.h
index 9315277d23..c0df5b0ce4 100644
--- a/src/include/crc_byte.h
+++ b/src/include/crc_byte.h
@@ -36,5 +36,24 @@ uint8_t crc7_byte(uint8_t prev_crc, uint8_t data);
*/
uint16_t crc16_byte(uint16_t prev_crc, uint8_t data);
+/* This function is used to calculate crc32 byte by byte, with polynomial
+ * x^32 + x^26 + x^23 + x^22 + x^16 + x^12 + x^11 + x^10 + x^8 + x^7 +
+ * x^5 + x^4 + x^2 + x + 1
+ *
+ * prev_crc: old crc result (0 for first)
+ * data: new byte
+ * return value: new crc result
+ */
+uint32_t crc32_byte(uint32_t prev_crc, uint8_t data);
+
+#define CRC(buf, size, crc_func) ({ \
+ const uint8_t *_crc_local_buf = (const uint8_t *)buf; \
+ size_t _crc_local_size = size; \
+ __typeof__(crc_func(0, 0)) _crc_local_result = 0; \
+ while (_crc_local_size--) { \
+ _crc_local_result = crc_func(_crc_local_result, *_crc_local_buf++); \
+ } \
+ _crc_local_result; \
+})
#endif /* CRC_BYTE_H */
diff --git a/src/lib/crc_byte.c b/src/lib/crc_byte.c
index 0ac006363a..c04449d13f 100644
--- a/src/lib/crc_byte.c
+++ b/src/lib/crc_byte.c
@@ -36,3 +36,17 @@ uint16_t crc16_byte(uint16_t prev_crc, uint8_t data)
prev_crc ^= ((prev_crc & 0xff) << 4) << 1;
return prev_crc;
}
+
+uint32_t crc32_byte(uint32_t prev_crc, uint8_t data)
+{
+ prev_crc ^= (uint32_t)data << 24;
+
+ for (int i = 0; i < 8; i++) {
+ if ((prev_crc & 0x80000000UL) != 0)
+ prev_crc = ((prev_crc << 1) ^ 0x04C11DB7UL);
+ else
+ prev_crc <<= 1;
+ }
+
+ return prev_crc;
+}