[BUG] mtd: rawnand: mircon: Cannot detect chip with commit 51f3b3970a8c

[boris.brezillon@xxxxxxxxxxx (Boris Brezillon)]

On Tue, 17 Jul 2018 21:59:16 +0000
Chris Packham <Chris.Packham at alliedtelesis.co.nz> wrote:

> Hi Dinh, Boris,
> 
> On 07/07/18 05:21, Boris Brezillon wrote:
> > On Fri, 6 Jul 2018 12:03:49 -0500
> > Dinh Nguyen <dinguyen at kernel.org> wrote:
> >   
> >> Hi,
> >>
> >> It looks like commit: "51f3b3970a8c mtd: rawnand: micron: detect forced
> >> on-die ECC" is causing the NAND chip on the SoCFPGA Arria10 devkit to
> >> stop working on linux-next.
> >>
> >> If I revert the commit, then the NAND driver is able to detect the NAND
> >> chip.
> >>
> >> The NAND chip is a Micron MT29F1G08ABBEAH4 part.
> >>
> >>
> >> [    0.741984] nand: device found, Manufacturer ID: 0x2c, Chip ID: 0xa1
> >> [    0.748336] nand: Micron MT29F1G08ABBEAH4
> >> [    0.752330] nand: 128 MiB, SLC, erase size: 128 KiB, page size: 2048,
> >> OOB siz
> >> e: 64
> >>   [    0.763358] ecc.mode = 3
> >> [    0.766312] On-die ECC forcefully enabled, not supported
> >> [    0.771654] denali-nand-dt: probe of ffb90000.nand failed with error -22
> >>
> >> With commit reverted:
> >>
> >> [    0.742481] nand: device found, Manufacturer ID: 0x2c, Chip ID: 0xa1
> >> [    0.748833] nand: Micron MT29F1G08ABBEAH4
> >> [    0.752828] nand: 128 MiB, SLC, erase size: 128 KiB, page size: 2048,
> >> OOB siz
> >> e: 64
> >> [    0.760610] Bad block table found at page 65472, version 0x01
> >> [    0.766433] Bad block table found at page 65408, version 0x01
> >> [    0.772464] 2 fixed-partitions partitions found on MTD device denali-nand
> >> [    0.779247] Creating 2 MTD partitions on "denali-nand":
> >> [    0.784453] 0x000000000000-0x000001c00000 : "Boot and fpga data"
> >> [    0.791241] 0x000001c00000-0x000008000000 : "Root Filesystem - JFFS2"
> >>
> >> Looks like if I comment out this part of the patch in
> >> drivers/mtd/nand/raw/nand_micron.c
> >>
> >> +#if 0
> >>          for (i = 0; i < ARRAY_SIZE(micron_on_die_ecc); i++)
> >>                  if (chip->id.data[1] == micron_on_die_ecc[i])
> >>                          return MICRON_ON_DIE_MANDATORY;
> >> -
> >> +#endif  
> > 
> > Oops, I overlooked that detail. Testing only the ID bytes is not
> > enough, because it does not encode whether the NAND has on-die ECC or
> > not. We should really test the model name here...
> > 
> > Chris, can you prepare a fixup for that?
> >   
> 
> With the latest set of changes is there anything left to do for this? I 
> think we now have on-die ECC detection that doesn't require checking the ID.

Yep, I think we're good. Thanks for you help.