Re: [PATCH 2/3] mtd: rawnand: arasan: Ensure program page operations are successful

Miquel Raynal
2023-09-22T09:14:44Z

Hi Michal,

michal.simek@amd.com wrote on Thu, 21 Sep 2023 12:25:10 +0200:

> On 9/12/23 16:17, Miquel Raynal wrote:
> > Hi Michal,
> >
> > michal.simek@amd.com wrote on Tue, 12 Sep 2023 15:55:23 +0200:
> >
> >> Hi Miquel,
> >>
> >> On 9/11/23 17:52, Miquel Raynal wrote:
> >>> Hi Michal,
> >>>
> >>> miquel.raynal@bootlin.com wrote on Mon, 17 Jul 2023 21:42:20 +0200:
> >>> >>>> The NAND core complies with the ONFI specification, which itself
> >>>> mentions that after any program or erase operation, a status check
> >>>> should be performed to see whether the operation was finished *and*
> >>>> successful.
> >>>>
> >>>> The NAND core offers helpers to finish a page write (sending the
> >>>> "PAGE PROG" command, waiting for the NAND chip to be ready again, and
> >>>> checking the operation status). But in some cases, advanced controller
> >>>> drivers might want to optimize this and craft their own page write
> >>>> helper to leverage additional hardware capabilities, thus not always
> >>>> using the core facilities.
> >>>>
> >>>> Some drivers, like this one, do not use the core helper to finish a page
> >>>> write because the final cycles are automatically managed by the
> >>>> hardware. In this case, the additional care must be taken to manually
> >>>> perform the final status check.
> >>>>
> >>>> Let's read the NAND chip status at the end of the page write helper and
> >>>> return -EIO upon error.
> >>>>
> >>>> Cc: Michal Simek <michal.simek@amd.com>
> >>>> Cc: stable@vger.kernel.org
> >>>> Fixes: 88ffef1b65cf ("mtd: rawnand: arasan: Support the hardware BCH ECC engine")
> >>>> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> >>>>
> >>>> ---
> >>>>
> >>>> Hello Michal,
> >>>>
> >>>> I have not tested this, but based on a report on another driver, I
> >>>> believe the status check is also missing here and could sometimes
> >>>> lead to unnoticed partial writes.
> >>>>
> >>>> Please test on your side that everything still works and let me
> >>>> know how it goes.
> >>>
> >>> Any news from the testing team about patches 2/3 and 3/3?
> >>
> >> I asked Amit to test and he didn't get back to me even I asked for it couple of times.
> >
> > Ok.
> >
> >> Can you please tell me how to test it? I will setup HW myself and test it and get back to you.
> >
> > I believe setting up the board to use the hardware BCH engine and
> > performing basic erase/write/read testing with a known file and check
> > it still behaves correctly would work. You can also run
> >
> > nandbiterrs -i /dev/mtdx
> >
> > as a second step and verify there is no difference with and without the
> > patch and finally check the impact:
> >
> > flash_speed -d -c 10 /dev/mtdx
> > (be careful: this is a destructive operation)
>
> Testing team won't see any issue that's why feel free to add my
> Acked-by: Michal Smek <michal.simek@amd.com>

I think you told me in the last e-mail you tested the pl353 patch, not
the one for the Arasan controller. Shall I add your Acked-by here and
your Tested-by in the other?

Thanks,
Miquèl