[PATCH 2/5] mtd: nand: add generic SPL NAND MTD loader

[dinesh.maniyam at altera.com]

From: Dinesh Maniyam <dinesh.maniyam at altera.com>

Add a generic SPL NAND MTD loader providing nand_get_mtd() and
nand_spl_load_image() helpers.

This allows SPL NAND MTD loading logic to be shared across NAND
controllers instead of being embedded in individual drivers.

Signed-off-by: Dinesh Maniyam <dinesh.maniyam at altera.com>
---
 drivers/mtd/nand/raw/spl_nand_mtd.c | 76 +++++++++++++++++++++++++++++
 1 file changed, 76 insertions(+)
 create mode 100644 drivers/mtd/nand/raw/spl_nand_mtd.c

diff --git a/drivers/mtd/nand/raw/spl_nand_mtd.c b/drivers/mtd/nand/raw/spl_nand_mtd.c
new file mode 100644
index 00000000000..06bd0b6ec88
--- /dev/null
+++ b/drivers/mtd/nand/raw/spl_nand_mtd.c
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright Altera Corporation (C) 2026. All rights reserved.
+ */
+
+#include <dm.h>
+#include <hang.h>
+#include <malloc.h>
+#include <memalign.h>
+#include <nand.h>
+
+struct mtd_info *nand_get_mtd(void)
+{
+	struct mtd_info *mtd;
+
+	mtd = get_nand_dev_by_index(nand_curr_device);
+	if (!mtd)
+		hang();
+
+	return mtd;
+}
+
+int nand_spl_load_image(u32 offset, u32 len, void *dst)
+{
+	size_t count = len, actual = 0, page_align_overhead = 0;
+	u32 page_align_offset = 0;
+	u8 *page_buffer = NULL;
+	int err = 0;
+	struct mtd_info *mtd;
+
+	if (!len || !dst)
+		return -EINVAL;
+
+	mtd = nand_get_mtd();
+
+	if (offset & (mtd->writesize - 1)) {
+		page_buffer = malloc_cache_aligned(mtd->writesize);
+		if (!page_buffer) {
+			debug("Error: allocating buffer\n");
+			return -ENOMEM;
+		}
+
+		page_align_overhead = offset % mtd->writesize;
+		page_align_offset = offset - page_align_overhead;
+		count = mtd->writesize;
+
+		err = nand_read_skip_bad(mtd, page_align_offset, &count,
+					 &actual, mtd->size, page_buffer);
+		if (err)
+			goto out;
+
+		count -= page_align_overhead;
+		count = min((size_t)len, count);
+
+		memcpy(dst, page_buffer + page_align_overhead, count);
+
+		len -= count;
+		if (!len)
+			goto out;
+
+		offset += count;
+		dst += count;
+		count = len;
+	}
+
+	err = nand_read_skip_bad(mtd, offset, &count,
+				 &actual, mtd->size, dst);
+
+out:
+	if (page_buffer)
+		free(page_buffer);
+
+	return err;
+}
+
+void nand_deselect(void) {}
-- 
2.43.7