Re: pxa3xx-nand failing to find device on linux-next

[Boris Brezillon <boris.brezillon@free-electrons.com>]

Le Thu, 25 May 2017 22:12:12 +0000,
Chris Packham <Chris.Packham@alliedtelesis.co.nz> a écrit :

> On 25/05/17 18:19, Boris Brezillon wrote:
> > Le Wed, 24 May 2017 22:58:53 +0000,
> > Chris Packham <Chris.Packham@alliedtelesis.co.nz> a écrit :
> >   
> >> On 25/05/17 10:36, Boris Brezillon wrote:  
> >>> Le Wed, 24 May 2017 22:03:52 +0000,
> >>> Chris Packham <Chris.Packham@alliedtelesis.co.nz> a écrit :
> >>>      
> >>>> On 24/05/17 23:25, Boris Brezillon wrote:  
> >>>>> On Wed, 24 May 2017 13:23:01 +0200
> >>>>> Boris Brezillon <boris.brezillon@free-electrons.com> wrote:
> >>>>>         
> >>>>>> Hi Chris,
> >>>>>>
> >>>>>> On Wed, 24 May 2017 09:36:56 +0000
> >>>>>> Chris Packham <Chris.Packham@alliedtelesis.co.nz> wrote:
> >>>>>>        
> >>>>>>> On 23/05/17 17:27, Chris Packham wrote:  
> >>>>>>>> Hi,
> >>>>>>>>
> >>>>>>>> I'm doing some testing on linux-next and I'm finding that my nand flash
> >>>>>>>> has disappeared.
> >>>>>>>>
> >>>>>>>> pxa3xx-nand f10d0000.flash: This platform can't do DMA on this device
> >>>>>>>> pxa3xx-nand f10d0000.flash: non-supported command ef
> >>>>>>>> pxa3xx-nand f10d0000.flash: non-supported command ee
> >>>>>>>> pxa3xx-nand f10d0000.flash: non-supported command ef
> >>>>>>>> pxa3xx-nand f10d0000.flash: non-supported command ee
> >>>>>>>> On-die ECC forcefully enabled, not supported
> >>>>>>>> nand: No NAND device found
> >>>>>>>> pxa3xx-nand f10d0000.flash: failed to scan nand at cs 0
> >>>>>>>>
> >>>>>>>> This was working around 4.11. I'll try to do some more digging tomorrow
> >>>>>>>> to narrow down a failure point but I thought I'd send this out now just
> >>>>>>>> in case it rings any bells.
> >>>>>>>>
> >>>>>>>> The board I'm using (DB-88F6820-AMC) is unfortunately out-of tree but it
> >>>>>>>> should be pretty close to the armada-388-db. I can make my dts available
> >>>>>>>> if it's helpful.  
> >>>>>>>
> >>>>>>> Still works on 4.12-rc2. Fails on next-20170524.
> >>>>>>>
> >>>>>>> This appears to be due to commit b566d9c055de ("mtd: nand: add support
> >>>>>>> for Micron on-die ECC"). Which based on the description seems intentional.
> >>>>>>>
> >>>>>>> Since I have access to a hardware platform that has a micron flash with
> >>>>>>> ECC forcefully enabled how can I help to get this implemented.  
> >>>>>>
> >>>>>> Can you try with this patch applied [1]?  
> >>>>>
> >>>>> Sorry, wrong patch. Can you try this one [1] instead?
> >>>>>
> >>>>> [1]http://code.bulix.org/pkfhmi-135875
> >>>>>         
> >>>>
> >>>> With the patch above the chip is detected but ubifs is unhappy  
> >>>
> >>> Hm, weird. And if you revert my both Thomas patch and mine, what do you
> >>> get?  
> >>
> >> Seems to work just fine.  
> > 
> > Okay. Let's try with something simpler then. Can you test the following
> > patch?
> >   
> > --->8---  
> >  From 0a0eaa39ea9b19191ae0c31ff3625c224a8a55f2 Mon Sep 17 00:00:00 2001
> > From: Boris Brezillon <boris.brezillon@free-electrons.com>
> > Date: Thu, 25 May 2017 08:15:15 +0200
> > Subject: [PATCH] mtd: nand: pxa3xx: Implement failing  
> >   ->onfi_{set,get}_features() stubs  
> > 
> > Implement stubs returning -ENOTSUPP for ->onfi_{set,get}_features() so
> > that we don't let the core think we are supporting the GET/SET FEATURES
> > operation.
> > 
> > Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
> > ---  
> 
> Yep that seems to work.

Arrggg!! I hate this situation. Now I have to check all drivers
implementing their own ->cmdfunc() to make sure they support
NAND_CMD_SET/GET_FEATURES, and if they don't, do what I did for pxa3xx.

Anyway, thanks for testing. I'll try to re-arrange my nand/next branch
to avoid breaking bisectibility (put this patch before the on-die ECC
one).

Regards,

Boris