[BUG] pxa3xx: wait time out when scanning for bb

Miquel RAYNAL miquel.raynal at free-electrons.com
Mon Dec 11 12:11:09 PST 2017


Hi Sean,

I don't remember having answered that, forgive me if I am repeating
myself.

On Mon,
11 Dec 2017 11:20:40 +0100 Sean Nyekjær <sean.nyekjaer at prevas.dk> wrote:

> Hi Miquel,
> > Actually, if you look carefully to the trace behind, you are not
> > using the same bad block table with the bootloader ("Bad block
> > table not found for chip 0") so the core then reads the OOB area of
> > every first page for each block and looks at the first OOB bytes
> > for the bad block markers. If there was data there, the block will
> > be declared as bad.  
> With the new NFC driver, is the bad block table located elsewhere?
> I have not done any changes to my bootloader when i did the switch to 
> the new driver,
> so i guess it should work as before.

The bad block table should always be located in the first pages of the
last blocks of the NAND chip. The data area contains the information.
Every pair of bits refers to a block. For each pair, b'11 means the
block is good. Otherwise it is marked bad (factory marked bad or became
bad). Multiple pages may be used if there is not enough space in one
page to fit the information about all the blocks. The spare area stores
the pattern that must start at offset 8 (It is "MVBbt0" in the case of
Marvell driver).

So yes, it should work as before. However, we can't really assume that
it actually "worked" before.

> > Can you please check that by using the configuration that actually
> > boots and use nanddump in raw mode with the OOB area (options -n
> > and -o) to show us the content of the first page of any block of
> > the last NAND MTD device?
> >
> >  
> Will do
> 
> /Sean



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