Reading From Nand; Unlocking Nand Address Space - Texas Instruments OMAP35 Series User Manual

3.5.5. Reading from NAND

To read len bytes of data from NAND block at offset to memory buffer located
at addr:
If a bad block is encountered during the read operation, it is skipped and the
read operation continues from next 'good' block.
For example, to read 0x40000 bytes from NAND - starting at block 32 (offset
0x400000) to memory buffer at address 0x80000000:

3.5.6. Unlocking NAND address space

To unlock NAND flash for writing
For example, to unlock block 32 (assuming erase block size of 128Kbytes)
Version 02.01.01.08
OMAP3EVM# nand write 0x80000000 0x400000 0x40000
OMAP3EVM# nand read <addr> <offset> <len>
Note
The behavior of this command was modified.
Important
If the read fails on ECC check, the block where the failure occurred is marked
bad and read operation is aborted. The command needs to be re- executed
to complete the read operation. But, the data in just marked bad block is
irrecoverably lost. The offset and length for reading have to be page aligned
else the command will abort.
OMAP3EVM# nand read 0x80000000 0x400000 0x40000
OMAP3EVM# nand unlock <offset> <len>
Note
This is a new command.
Platform Support Products
U-Boot
Reading from NAND
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