From: Thomas Gleixner tglx@linutronix.de
To support UBI in SPL we need a simple flash read function. Add one to nand_spl_simple and keep it as simple as it goes.
Signed-off-by: Thomas Gleixner tglx@linutronix.de --- drivers/mtd/nand/nand_spl_simple.c | 64 ++++++++++++++++++++++++++++++++++++++ include/nand.h | 1 + 2 files changed, 65 insertions(+)
diff --git a/drivers/mtd/nand/nand_spl_simple.c b/drivers/mtd/nand/nand_spl_simple.c index e69f662..2e1af53 100644 --- a/drivers/mtd/nand/nand_spl_simple.c +++ b/drivers/mtd/nand/nand_spl_simple.c @@ -209,6 +209,70 @@ 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_flash - Read data from flash into a buffer + * @pnum: Number of the physical eraseblock + * @offset: Data offset from the start of @pnum + * @len: Data size to read + * @dest: 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 its a non issue anyway. + */ +int nand_spl_read_flash(u32 pnum, u32 offset, u32 len, void *dest) +{ + u32 offs, page, read, toread = len; + + /* Calculate the page number */ + page = offset / CONFIG_SYS_NAND_PAGE_SIZE; + + /* Offset to the start of a flash page */ + offs = offset % CONFIG_SYS_NAND_PAGE_SIZE; + + while (toread) { + /* + * Non page aligned reads go to the scratch buffer. + * Page aligned reads go directly to the destination. + */ + if (offs || toread < CONFIG_SYS_NAND_PAGE_SIZE) { + nand_read_page(pnum, page, scratch_buf); + read = min(len, toread); + read = min(read, CONFIG_SYS_NAND_PAGE_SIZE - offs); + memcpy(dest, scratch_buf + offs, read); + offs = 0; + } else { + nand_read_page(pnum, page, dest); + read = CONFIG_SYS_NAND_PAGE_SIZE; + } + page++; + toread -= read; + dest += read; + } + return 0; +} +#endif + int nand_spl_load_image(uint32_t offs, unsigned int size, void *dst) { unsigned int block, lastblock; diff --git a/include/nand.h b/include/nand.h index d2a53ab..b8bc952 100644 --- a/include/nand.h +++ b/include/nand.h @@ -124,6 +124,7 @@ int nand_unlock(nand_info_t *meminfo, loff_t start, size_t length, int nand_get_lock_status(nand_info_t *meminfo, loff_t offset);
int nand_spl_load_image(uint32_t offs, unsigned int size, void *dst); +int nand_spl_read_flash(u32 pnum, u32 offset, u32 len, void *dest); void nand_deselect(void);
#ifdef CONFIG_SYS_NAND_SELECT_DEVICE