From e1a89e9358b8cedd98ad346cccd08e1bca669072 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 12 Jul 2016 20:28:10 +0200 Subject: 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: Thomas Gleixner Signed-off-by: Ladislav Michl Acked-by: Scott Wood Reviewed-by: Tom Rini Reviewed-by: Heiko Schocher --- drivers/mtd/nand/nand_spl_simple.c | 62 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) (limited to 'drivers/mtd') diff --git a/drivers/mtd/nand/nand_spl_simple.c b/drivers/mtd/nand/nand_spl_simple.c index 60a7607..55f48d3 100644 --- a/drivers/mtd/nand/nand_spl_simple.c +++ b/drivers/mtd/nand/nand_spl_simple.c @@ -209,6 +209,68 @@ static int nand_read_page(int block, int page, void *dst) } #endif +#ifdef CONFIG_SPL_UBI +/* + * 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); + read = CONFIG_SYS_NAND_PAGE_SIZE; + } + page++; + len -= read; + dst += read; + } + return 0; +} +#endif + int nand_spl_load_image(uint32_t offs, unsigned int size, void *dst) { unsigned int block, lastblock; -- cgit v1.1