From f8108cbf0e0ffd4ed82b22142fcea5d9174ba98f Mon Sep 17 00:00:00 2001
From: Daniel Willenson <dwillens@hotmail.com>
Date: Tue, 5 May 2026 15:22:34 -0400
Subject: [PATCH] add TMS570_ISO configuration

* as documented in https://www.ti.com/lit/an/spna235/spna235.pdf
---
 fastcrc/crc64.py | 23 ++++++++++++++++++++++-
 src/lib.rs       | 13 +++++++++++++
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/fastcrc/crc64.py b/fastcrc/crc64.py
index 634c502..e25d9a8 100644
--- a/fastcrc/crc64.py
+++ b/fastcrc/crc64.py
@@ -7,8 +7,9 @@
 from .fastcrc import crc_64_go_iso as _crc_64_go_iso
 from .fastcrc import crc_64_we as _crc_64_we
 from .fastcrc import crc_64_xz as _crc_64_xz
+from .fastcrc import crc_64_tms570_iso as _crc_64_tms570_iso
 
-__always_supported = ("ecma_182", "go_iso", "we", "xz")
+__always_supported = ("ecma_182", "go_iso", "we", "xz", "tms570_iso")
 
 algorithms_guaranteed = set(__always_supported)
 algorithms_available = set(__always_supported)
@@ -92,3 +93,23 @@ def xz(data: bytes, initial: Optional[int] = None) -> int:
     :raises TypeError: if the data is not a bytes-like object
     """
     return _crc_64_xz(data, initial)
+
+
+def tms570_iso(data: bytes, initial: Optional[int] = None) -> int:
+    """
+    Compute a CRC-64 checksum of data with the `tms570_iso` algorithm.
+
+    Algorithm parameters:
+        - poly: 0x000000000000001b
+        - init: 0x0000000000000000
+        - xorout: 0x0000000000000000
+        - refin: False
+        - refout: False
+
+    :param bytes data: The data to be computed
+    :param Optional[int] initial: The optional starting value of the checksum
+    :return: The checksum
+    :rtype: int
+    :raises TypeError: if the data is not a bytes-like object
+    """
+    return _crc_64_tms570_iso(data, initial)
diff --git a/src/lib.rs b/src/lib.rs
index f94aafc..245b836 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -65,6 +65,17 @@ const CRC_32_K_REVERSED_RECIPROCAL_REFIN: Algorithm<u32> = Algorithm {
     residue: 0x00000000,
 };
 
+const CRC_64_TMS570_ISO: Algorithm<u64> = Algorithm {
+    width: 64,
+    poly: 0x000000000000001b,
+    init: 0x0000000000000000,
+    refin: false,
+    refout: false,
+    xorout: 0x0000000000000000,
+    check: 0xe4ffbea588933790,
+    residue: 0x0000000000000000,
+};
+
 define_crc_fn!(crc_8_autosar, u8, CRC_8_AUTOSAR);
 define_crc_fn!(crc_8_bluetooth, u8, CRC_8_BLUETOOTH);
 define_crc_fn!(crc_8_cdma2000, u8, CRC_8_CDMA2000);
@@ -135,6 +146,7 @@ define_crc_fn!(crc_64_ecma_182, u64, CRC_64_ECMA_182);
 define_crc_fn!(crc_64_go_iso, u64, CRC_64_GO_ISO);
 define_crc_fn!(crc_64_we, u64, CRC_64_WE);
 define_crc_fn!(crc_64_xz, u64, CRC_64_XZ);
+define_crc_fn!(crc_64_tms570_iso, u64, CRC_64_TMS570_ISO);
 
 #[pymodule(gil_used = false)]
 fn fastcrc(m: &Bound<'_, PyModule>) -> PyResult<()> {
@@ -204,5 +216,6 @@ fn fastcrc(m: &Bound<'_, PyModule>) -> PyResult<()> {
     m.add_function(wrap_pyfunction!(crc_64_go_iso, m)?)?;
     m.add_function(wrap_pyfunction!(crc_64_we, m)?)?;
     m.add_function(wrap_pyfunction!(crc_64_xz, m)?)?;
+    m.add_function(wrap_pyfunction!(crc_64_tms570_iso, m)?)?;
     Ok(())
 }