Re: [PATCH] mtd: nand: raw: qcom_nandc: Don't clear_bam_transaction on READID

[Sricharan Ramabadhran]

Hi Konrad,

On 1/28/2022 9:55 AM, Sricharan Ramabadhran wrote:
> Hi Miquel,
>
> On 1/26/2022 4:12 PM, Miquel Raynal wrote:
> > Hi Mani,
> >
> > mani@xxxxxxxxxx wrote on Wed, 26 Jan 2022 16:03:16 +0530:
> >
> > > On Wed, Jan 26, 2022 at 11:16:13AM +0100, Miquel Raynal wrote:
> > > > Hello,
> > > >
> > > > miquel.raynal@xxxxxxxxxxx wrote on Fri, 14 Jan 2022 08:27:18 +0100:
> > > > > Hi Konrad,
> > > > >
> > > > > konrad.dybcio@xxxxxxxxxxxxxx wrote on Thu, 13 Jan 2022 19:44:26 
> > > > > +0100:
> > > > > > While I have absolutely 0 idea why and how, running 
> > > > > > clear_bam_transaction
> > > > > > when READID is issued makes the DMA totally clog up and refuse to 
> > > > > > function
> > > > > > at all on mdm9607. In fact, it is so bad that all the data gets 
> > > > > > garbled
> > > > > > and after a short while in the nand probe flow, the CPU decides that
> > > > > > sepuku is the only option.
> > > > > >
> > > > > > Removing _READID from the if condition makes it work like a 
> > > > > > charm, I can
> > > > > > read data and mount partitions without a problem.
> > > > > >
> > > > > > Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxx>
> > > > > > ---
> > > > > > This is totally just an observation which took me an inhumane 
> > > > > > amount of
> > > > > > debug prints to find.. perhaps there's a better reason behind 
> > > > > > this, but
> > > > > > I can't seem to find any answers.. Therefore, this is a BIG RFC!
> > > > > I'm adding two people from codeaurora who worked a lot on this 
> > > > > driver.
> > > > > Hopefully they will have an idea :)
> > > > Sadre, I've spent a significant amount of time reviewing your patches,
> > > > now it's your turn to not take a month to answer to your peers
> > > > proposals.
> > > >
> > > > Please help reviewing this patch.
> > > Sorry. I was hoping that Qcom folks would chime in as I don't have 
> > > any idea
> > > about the mdm9607 platform. It could be that the mail server 
> > > migration from
> > > codeaurora to quicinc put a barrier here.
> > >
> > > Let me ping them internally.
> > Oh, ok, I didn't know. Thanks!
>
>    Sorry Miquel, somehow we did not get this email in our inbox.
>    Thanks to Mani for pinging us, we will test this up today and get 
> back.
      While we could not reproduce this issue on our ipq boards (do not 
have a mdm9607 right now) and
       issue does not look any obvious.
      can you please give the debug logs that you did for the above 
stage by stage ?

  Regards,
      Sricharan