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

[Miquel RAYNAL <miquel.raynal@free-electrons.com>]

Hi Sean,


> > Also, what kernel are you using ?  
> 4.14.0 :-)

Good !

> [    2.288684] pxa3xx-nand f10d0000.flash: This platform can't do DMA
> on this device

FYI, this is normal, the NAND controller does not have any DMA feature
on Armada 38x (NFCv2).

> [    2.296924] nand: device found, Manufacturer ID: 0x2c, Chip ID:
> 0xda [    2.303311] nand: Micron MT29F2G08ABAEAH4
> [    2.307334] nand: 256 MiB, SLC, erase size: 128 KiB, page size:
> 2048, OOB size: 64
> [    2.314939] pxa3xx-nand f10d0000.flash: ECC strength 16, ECC step 
> size 2048

In theory, Marvell NAND flash controller does support 16-bit strength
per 512 bytes over 2048 bytes pages. However, this controller driver
(pxa3xx_nand) does not. See [1] for the supported configurations.

The ECC strength shown here is probably the best to use with this type
of NAND device but I suggest you try with 4b/512B by using these two
properties like in [2]:

        nand-ecc-strength = <4>;
        nand-ecc-step-size = <512>;


Thanks,
Miquèl

[1]
http://elixir.free-electrons.com/linux/v4.14/source/drivers/mtd/nand/pxa3xx_nand.c#L1575

[2]
http://elixir.free-electrons.com/linux/v4.14/source/arch/arm/boot/dts/armada-385-db-ap.dts#L172