nand: atmel: Add pmecc driver

Add driver for atmel pmecc. This implementation is ported from
Linux. The reference taken is linux-5.4-at91.

Signed-off-by: Balamanikandan Gunasundar <balamanikandan.gunasundar@microchip.com>
diff --git a/drivers/mtd/nand/raw/atmel/pmecc.h b/drivers/mtd/nand/raw/atmel/pmecc.h
new file mode 100644
index 0000000..43f96b2
--- /dev/null
+++ b/drivers/mtd/nand/raw/atmel/pmecc.h
@@ -0,0 +1,94 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * © Copyright 2016 ATMEL
+ * © Copyright 2016 Free Electrons
+ *
+ * Author: Boris Brezillon <boris.brezillon@free-electrons.com>
+ *
+ * Derived from the atmel_nand.c driver which contained the following
+ * copyrights:
+ *
+ *    Copyright © 2003 Rick Bronson
+ *
+ *    Derived from drivers/mtd/nand/autcpu12.c (removed in v3.8)
+ *        Copyright © 2001 Thomas Gleixner (gleixner@autronix.de)
+ *
+ *    Derived from drivers/mtd/spia.c (removed in v3.8)
+ *        Copyright © 2000 Steven J. Hill (sjhill@cotw.com)
+ *
+ *
+ *    Add Hardware ECC support for AT91SAM9260 / AT91SAM9263
+ *        Richard Genoud (richard.genoud@gmail.com), Adeneo Copyright © 2007
+ *
+ *        Derived from Das U-Boot source code
+ *              (u-boot-1.1.5/board/atmel/at91sam9263ek/nand.c)
+ *        © Copyright 2006 ATMEL Rousset, Lacressonniere Nicolas
+ *
+ *    Add Programmable Multibit ECC support for various AT91 SoC
+ *        © Copyright 2012 ATMEL, Hong Xu
+ *
+ *    Add Nand Flash Controller support for SAMA5 SoC
+ *        © Copyright 2013 ATMEL, Josh Wu (josh.wu@atmel.com)
+ */
+
+#ifndef ATMEL_PMECC_H
+#define ATMEL_PMECC_H
+
+#define ATMEL_PMECC_MAXIMIZE_ECC_STRENGTH	0
+#define ATMEL_PMECC_SECTOR_SIZE_AUTO		0
+#define ATMEL_PMECC_OOBOFFSET_AUTO		-1
+
+struct atmel_pmecc_user_req {
+	int pagesize;
+	int oobsize;
+	struct {
+		int strength;
+		int bytes;
+		int sectorsize;
+		int nsectors;
+		int ooboffset;
+	} ecc;
+};
+
+struct atmel_pmecc_suspend_ctx {
+	u32 setup;
+	u32 pulse;
+	u32 cycle;
+	u32 timings;
+	u32 mode;
+};
+
+struct atmel_pmecc {
+	struct udevice *dev;
+	const struct atmel_pmecc_caps *caps;
+
+	struct {
+		void __iomem *base;
+		void __iomem *errloc;
+		void __iomem *timing;
+	} regs;
+
+	/* Mutex used for pmecc enable/disable */
+	struct mutex lock;
+
+	struct atmel_pmecc_suspend_ctx suspend;
+};
+
+struct atmel_pmecc *devm_atmel_pmecc_get(struct udevice *dev);
+
+struct atmel_pmecc_user *
+atmel_pmecc_create_user(struct atmel_pmecc *pmecc,
+			struct atmel_pmecc_user_req *req);
+void atmel_pmecc_destroy_user(struct atmel_pmecc_user *user);
+
+void atmel_pmecc_reset(struct atmel_pmecc *pmecc);
+int atmel_pmecc_enable(struct atmel_pmecc_user *user, int op);
+void atmel_pmecc_disable(struct atmel_pmecc_user *user);
+int atmel_pmecc_wait_rdy(struct atmel_pmecc_user *user);
+int atmel_pmecc_correct_sector(struct atmel_pmecc_user *user, int sector,
+			       void *data, void *ecc);
+bool atmel_pmecc_correct_erased_chunks(struct atmel_pmecc_user *user);
+void atmel_pmecc_get_generated_eccbytes(struct atmel_pmecc_user *user,
+					int sector, void *ecc);
+
+#endif /* ATMEL_PMECC_H */