[PATCH u-boot-mvebu v2 33/41] SPL: Add support for specifying offset between header and image

[Marek Behún]

From: Pali Rohár <pali at kernel.org>

Some image types (e.g. kwbimage v1) store the offset to SPL binary and
offset to main U-Boot binary in their headers. To avoid reading SPL
binary when loading main U-Boot, add support for specifying offset in
struct spl_image_info, which defines the offset from the beginning of
the header and the beginning of the executable data.

Initial support is added only for SPI, MMC and SATA code. We can extend
it later if needed.

Signed-off-by: Pali Rohár <pali at kernel.org>
Reviewed-by: Marek Behún <marek.behun at nic.cz>
---
 common/spl/spl_mmc.c  | 16 +++++++++++++++-
 common/spl/spl_sata.c | 12 +++++++++++-
 common/spl/spl_spi.c  |  2 +-
 include/spl.h         |  1 +
 4 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/common/spl/spl_mmc.c b/common/spl/spl_mmc.c
index add2785b4e..5605f1820d 100644
--- a/common/spl/spl_mmc.c
+++ b/common/spl/spl_mmc.c
@@ -20,26 +20,40 @@
 static int mmc_load_legacy(struct spl_image_info *spl_image, struct mmc *mmc,
 			   ulong sector, struct image_header *header)
 {
+	u32 image_offset_sectors;
 	u32 image_size_sectors;
 	unsigned long count;
+	u32 image_offset;
 	int ret;
 
 	ret = spl_parse_image_header(spl_image, header);
 	if (ret)
 		return ret;
 
+	/* convert offset to sectors - round down */
+	image_offset_sectors = spl_image->offset / mmc->read_bl_len;
+	/* calculate remaining offset */
+	image_offset = spl_image->offset % mmc->read_bl_len;
+
 	/* convert size to sectors - round up */
 	image_size_sectors = (spl_image->size + mmc->read_bl_len - 1) /
 			     mmc->read_bl_len;
 
 	/* Read the header too to avoid extra memcpy */
-	count = blk_dread(mmc_get_blk_desc(mmc), sector, image_size_sectors,
+	count = blk_dread(mmc_get_blk_desc(mmc),
+			  sector + image_offset_sectors,
+			  image_size_sectors,
 			  (void *)(ulong)spl_image->load_addr);
 	debug("read %x sectors to %lx\n", image_size_sectors,
 	      spl_image->load_addr);
 	if (count != image_size_sectors)
 		return -EIO;
 
+	if (image_offset)
+		memmove((void *)(ulong)spl_image->load_addr,
+			(void *)(ulong)spl_image->load_addr + image_offset,
+			spl_image->size);
+
 	return 0;
 }
 
diff --git a/common/spl/spl_sata.c b/common/spl/spl_sata.c
index e108af0576..535a9219ef 100644
--- a/common/spl/spl_sata.c
+++ b/common/spl/spl_sata.c
@@ -36,6 +36,8 @@ static int spl_sata_load_image_raw(struct spl_image_info *spl_image,
 	struct image_header *header;
 	unsigned long count;
 	u32 image_size_sectors;
+	u32 image_offset_sectors;
+	u32 image_offset;
 	int ret;
 
 	header = spl_get_load_buffer(-sizeof(*header), stor_dev->blksz);
@@ -48,11 +50,19 @@ static int spl_sata_load_image_raw(struct spl_image_info *spl_image,
 		return ret;
 
 	image_size_sectors = DIV_ROUND_UP(spl_image->size, stor_dev->blksz);
-	count = blk_dread(stor_dev, sector, image_size_sectors,
+	image_offset_sectors = spl_image->offset / stor_dev->blksz;
+	image_offset = spl_image->offset % stor_dev->blksz;
+	count = blk_dread(stor_dev, sector + image_offset_sectors,
+			image_size_sectors,
 			(void *)spl_image->load_addr);
 	if (count != image_size_sectors)
 		return -EIO;
 
+	if (image_offset)
+		memmove((void *)spl_image->load_addr,
+			(void *)spl_image->load_addr + image_offset,
+			spl_image->size);
+
 	return 0;
 }
 
diff --git a/common/spl/spl_spi.c b/common/spl/spl_spi.c
index 6a4e033287..9884e7c185 100644
--- a/common/spl/spl_spi.c
+++ b/common/spl/spl_spi.c
@@ -159,7 +159,7 @@ static int spl_spi_load_image(struct spl_image_info *spl_image,
 			err = spl_parse_image_header(spl_image, header);
 			if (err)
 				return err;
-			err = spi_flash_read(flash, payload_offs,
+			err = spi_flash_read(flash, payload_offs + spl_image->offset,
 					     spl_image->size,
 					     (void *)spl_image->load_addr);
 		}
diff --git a/include/spl.h b/include/spl.h
index cee9a42ddb..3df923a813 100644
--- a/include/spl.h
+++ b/include/spl.h
@@ -198,6 +198,7 @@ struct spl_image_info {
 	void *fdt_addr;
 #endif
 	u32 boot_device;
+	u32 offset;
 	u32 size;
 	u32 flags;
 	void *arg;
-- 
2.31.1