Commit e1a89e93 authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Tom Rini

nand_spl_simple: Add a simple NAND read function

To support UBI in SPL we need a simple NAND read function. Add one to
nand_spl_simple and keep it as simple as it goes.
Signed-off-by: default avatarThomas Gleixner <>
Signed-off-by: default avatarLadislav Michl <>
Acked-by: default avatarScott Wood <>
Reviewed-by: default avatarTom Rini <>
Reviewed-by: default avatarHeiko Schocher <>
parent 05fc5ef1
......@@ -209,6 +209,68 @@ static int nand_read_page(int block, int page, void *dst)
* Temporary storage for non NAND page aligned and non NAND page sized
* reads. Note: This does not support runtime detected FLASH yet, but
* that should be reasonably easy to fix by making the buffer large
* enough :)
static u8 scratch_buf[CONFIG_SYS_NAND_PAGE_SIZE];
* nand_spl_read_block - Read data from physical eraseblock into a buffer
* @block: Number of the physical eraseblock
* @offset: Data offset from the start of @peb
* @len: Data size to read
* @dst: Address of the destination buffer
* This could be further optimized if we'd have a subpage read
* function in the simple code. On NAND which allows subpage reads
* this would spare quite some time to readout e.g. the VID header of
* UBI.
* Notes:
* @offset + @len are not allowed to be larger than a physical
* erase block. No sanity check done for simplicity reasons.
* To support runtime detected flash this needs to be extended by
* information about the actual flash geometry, but thats beyond the
* scope of this effort and for most applications where fast boot is
* required it is not an issue anyway.
int nand_spl_read_block(int block, int offset, int len, void *dst)
int page, read;
/* Calculate the page number */
page = offset / CONFIG_SYS_NAND_PAGE_SIZE;
/* Offset to the start of a flash page */
offset = offset % CONFIG_SYS_NAND_PAGE_SIZE;
while (len) {
* Non page aligned reads go to the scratch buffer.
* Page aligned reads go directly to the destination.
if (offset || len < CONFIG_SYS_NAND_PAGE_SIZE) {
nand_read_page(block, page, scratch_buf);
read = min(len, CONFIG_SYS_NAND_PAGE_SIZE - offset);
memcpy(dst, scratch_buf + offset, read);
offset = 0;
} else {
nand_read_page(block, page, dst);
len -= read;
dst += read;
return 0;
int nand_spl_load_image(uint32_t offs, unsigned int size, void *dst)
unsigned int block, lastblock;
......@@ -122,6 +122,7 @@ int nand_unlock(struct mtd_info *mtd, loff_t start, size_t length,
int nand_get_lock_status(struct mtd_info *mtd, loff_t offset);
int nand_spl_load_image(uint32_t offs, unsigned int size, void *dst);
int nand_spl_read_block(int block, int offset, int len, void *dst);
void nand_deselect(void);
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