Re: [linux-next:master 1937/6910] drivers/mtd/nand/raw/qcom_nandc.c:2941 qcom_op_cmd_mapping() error: uninitialized symbol 'ret'.

[Miquel Raynal <miquel.raynal@bootlin.com>]

Hi Sricharan,

quic_srichara@quicinc.com wrote on Fri, 18 Aug 2023 19:21:04 +0530:

> Hi Miquel,
> 
> On 8/18/2023 7:03 PM, Miquel Raynal wrote:
> > Hi Sricharan,
> > 
> > quic_srichara@quicinc.com wrote on Tue, 8 Aug 2023 10:46:14 +0530:
> >   
> >> <..>
> >>  
> >>>>     With this series applied on linux-next, started seeing the below
> >>>>     messages flooded on console while doing mtd r/w.
> >>>>     "xxx "Opcode not supported: 0"
> >>>>
> >>>>     opcode '0' corresponds to NAND_CMD_READ0. This command inturn was
> >>>>     invoked from qcom_nandc.c driver from below places. For read/write_page
> >>>>     driver does not use the exec ops. Hence these calls just ends up
> >>>>     being -ENOTSUPP and ignored. So removed their invocations.
> >>>>     If this is fine, can this be added to your series ? (will send
> >>>>     git-format patch to add to your cleanup series). So far, tested
> >>>>     mtd raw/block read/writes and all works fine. Will do further tests
> >>>>     as well.  
> >>>
> >>> Unless I really don't understand the controller, this is non sense.
> >>> nand_read_page_op() is precisely what allows your NAND to perform a
> >>> read. Removing this call cannot work.
> >>>
> >>> What you need is a proper ->exec_op() implementation, and repeating
> >>> this becomes slightly annoying.
> >>>
> >>> Look at your qcom_op_cmd_mapping, you don't even have a path for reads.
> >>> I bet something along:
> >>> 	CMD_READ0:
> >>> 		ret = XXX_OPCODE_READ;
> >>> 		break;
> >>> will make it work.
> >>>
> >>> Please fix the driver and test with nandbiterrs -i. If this test works,
> >>> it is encouraging. Otherwise it is still broken.  
> >>
> >>    ok understand. Will fix this up.  
> > 
> > This is urgent now. The driver in -next is broken, shall I revert
> > everything or will you test the above fix quickly?
> >   
> 
>    While we are able to reproduce the issue, add path for
>    CMD_READ0/READ_START for IPQ platforms. All mtd tests including
>    nandbiterrs works fine.  But we are not able to get hold of a SDX
>    device where we could reproduce the issue to debug. We are working
>    offline with Manivannan for the SDX remote debug. Will keep you
>    updated here and if we are not able to solve this on SDX in next
>    couple of days, only way looks like revert and re-apply it for 6.7.

If the READ path works on IPQ platforms it's already a huge step
forward, please send the fix on top of Mannivan series.

Now, what is the issue with SDX?

Thanks,
Miquèl