spl: Extract legacy image handling into separate file

This patch moves the legacy image handling into a separate file, which
will be extended with other legacy image features later.

No function change intended.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Weijie Gao <weijie.gao@mediatek.com>
Cc: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
diff --git a/common/spl/spl_legacy.c b/common/spl/spl_legacy.c
new file mode 100644
index 0000000..33f3587
--- /dev/null
+++ b/common/spl/spl_legacy.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2020 Stefan Roese <sr@denx.de>
+ */
+
+#include <common.h>
+#include <spl.h>
+
+int spl_parse_legacy_header(struct spl_image_info *spl_image,
+			    const struct image_header *header)
+{
+	u32 header_size = sizeof(struct image_header);
+
+#ifdef CONFIG_SPL_LEGACY_IMAGE_CRC_CHECK
+	/* check uImage header CRC */
+	if (!image_check_hcrc(header)) {
+		puts("SPL: Image header CRC check failed!\n");
+		return -EINVAL;
+	}
+#endif
+
+	if (spl_image->flags & SPL_COPY_PAYLOAD_ONLY) {
+		/*
+		 * On some system (e.g. powerpc), the load-address and
+		 * entry-point is located at address 0. We can't load
+		 * to 0-0x40. So skip header in this case.
+		 */
+		spl_image->load_addr = image_get_load(header);
+		spl_image->entry_point = image_get_ep(header);
+		spl_image->size = image_get_data_size(header);
+	} else {
+		spl_image->entry_point = image_get_ep(header);
+		/* Load including the header */
+		spl_image->load_addr = image_get_load(header) -
+			header_size;
+		spl_image->size = image_get_data_size(header) +
+			header_size;
+	}
+
+#ifdef CONFIG_SPL_LEGACY_IMAGE_CRC_CHECK
+	/* store uImage data length and CRC to check later */
+	spl_image->dcrc_data = image_get_load(header);
+	spl_image->dcrc_length = image_get_data_size(header);
+	spl_image->dcrc = image_get_dcrc(header);
+#endif
+
+	spl_image->os = image_get_os(header);
+	spl_image->name = image_get_name(header);
+	debug(SPL_TPL_PROMPT
+	      "payload image: %32s load addr: 0x%lx size: %d\n",
+	      spl_image->name, spl_image->load_addr, spl_image->size);
+
+	return 0;
+}