On 09/12/2011 01:24 PM, Marek Vasut wrote: > On Monday, September 12, 2011 08:06:27 PM Scott Wood wrote: >> On 09/12/2011 12:45 PM, Marek Vasut wrote: >>> On Monday, September 12, 2011 06:45:43 PM Mike Frysinger wrote: >>>> On Monday, September 12, 2011 00:04:10 Marek Vasut wrote: >>>>> This allows the scrub command to scrub without asking the user if he >>>>> really wants to scrub the area. Useful in scripts. >>>> >>>> "quiet" and "skip user input" are two different things. can you use a >>>> more clean option like accepting "-y" to the "scrub" subcommand ? >>> >>> I'd prefer to have this hidden from common users as much as possible. >> >> What's the use case for needing to script this, BTW? > > Update a block in NAND that's not handled by BCH accelerator in the MX28 chip. > > The problem is, block 0 has it's own ECC done by bootrom software. That kind > of > ECC is incompatible with BCH-produced ECC. That's also a reason for needing > that > write.raw command. > > Now, if you try erasing that block, the BCH reads and writes some of it's > metadata there. Obviously, since there is different kind of ECC, the metadata > aren't there and it chokes, claiming the block is bad and refuses to erase it. > > And before you ask why -- that's because the BCH accelerator puts the > metadata > at random places in the block (every 512 bytes, it puts a few bytes of it's > ECC) > instead of putting them only to the ECC area. On the other hand, the bootrom > ECC > puts the whole ECC at offset (1024 + 12) bytes from the start of the block 0.
Would it make sense to have the driver code treat block 0 specially (possibly conditioned on an hwconfig or compile-time config), rather than have it be user-driven? I'm curious why anything is written on an erase, though, regardless of data format. -Scott _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
