mtd: devices: elm: Add support for ELM error correction

The ELM hardware module can be used to speedup BCH 4/8/16 ECC scheme
error correction.
For now only 4 & 8 bit support is added

Signed-off-by: Philip Avinash <avinashphilip@ti.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

1 files changed, 53 insertions, 0 deletions

diff --git a/include/linux/platform_data/elm.h b/include/linux/platform_data/elm.h
new file mode 100644
index 000000000000..11ab6aaf2431
--- /dev/null
+++ b/include/linux/platform_data/elm.h
@@ -0,0 +1,53 @@
+/*
+ * BCH Error Location Module
+ *
+ * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef __ELM_H
+#define __ELM_H
+
+enum bch_ecc {
+	BCH4_ECC = 0,
+	BCH8_ECC,
+};
+
+/* ELM support 8 error syndrome process */
+#define ERROR_VECTOR_MAX		8
+
+#define BCH8_ECC_OOB_BYTES		13
+#define BCH4_ECC_OOB_BYTES		7
+/* RBL requires 14 byte even though BCH8 uses only 13 byte */
+#define BCH8_SIZE			(BCH8_ECC_OOB_BYTES + 1)
+#define BCH4_SIZE			(BCH4_ECC_OOB_BYTES)
+
+/**
+ * struct elm_errorvec - error vector for elm
+ * @error_reported:		set true for vectors error is reported
+ * @error_uncorrectable:	number of uncorrectable errors
+ * @error_count:		number of correctable errors in the sector
+ * @error_loc:			buffer for error location
+ *
+ */
+struct elm_errorvec {
+	bool error_reported;
+	bool error_uncorrectable;
+	int error_count;
+	int error_loc[ERROR_VECTOR_MAX];
+};
+
+void elm_decode_bch_error_page(struct device *dev, u8 *ecc_calc,
+		struct elm_errorvec *err_vec);
+void elm_config(struct device *dev, enum bch_ecc bch_type);
+#endif /* __ELM_H */