Re: [PATCH] mtd: rawnand: qcom: Fix DMA sync on FLASH_STATUS register read

From: Miquel Raynal
Date: Wed Oct 28 2020 - 17:41:48 EST


Hello,

Praveenkumar I <ipkumar@xxxxxxxxxxxxxx> wrote on Wed, 28 Oct 2020
19:48:34 +0530:

> Hi Miquel,
>
> Please find the inline reply.
>
> Thanks,
> Praveenkumar I
>
>
> On 10/28/2020 3:38 PM, Miquel Raynal wrote:
> > Hello,
> >
> > Praveenkumar I <ipkumar@xxxxxxxxxxxxxx> wrote on Fri, 9 Oct 2020
> > 13:37:52 +0530:
> >
> >> After each codeword NAND_FLASH_STATUS is read for possible operational
> >> failures. But there is no DMA sync for CPU operation before reading it
> >> and this leads to incorrect or older copy of DMA buffer in reg_read_buf.
> >>
> >> This patch adds the DMA sync on reg_read_buf for CPU before reading it.
> >>
> >> Fixes: 5bc36b2bf6e2 ("mtd: rawnand: qcom: check for operation errors in case of raw read")
> > I guess this deserves a proper Cc: stable tag?
> > >> Yes. I will send a V2 Patch with stable tag in Cc

That's fine for this one, I'll add it myself.

> >> Signed-off-by: Praveenkumar I <ipkumar@xxxxxxxxxxxxxx>
> > I think your full name is required in the SoB line (should match the
> > authorship).
> > >> "Praveenkumar I" is my full name and it is same as the authorship.

Ok, sorry for the confusion.

> > Otherwise looks good to me.
> >
> >> ---
> >> drivers/mtd/nand/raw/qcom_nandc.c | 2 ++
> >> 1 file changed, 2 insertions(+)
> >>
> >> diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
> >> index bd7a7251429b..5bb85f1ba84c 100644
> >> --- a/drivers/mtd/nand/raw/qcom_nandc.c
> >> +++ b/drivers/mtd/nand/raw/qcom_nandc.c
> >> @@ -1570,6 +1570,8 @@ static int check_flash_errors(struct qcom_nand_host *host, int cw_cnt)
> >> struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
> >> int i;
> >> >> + nandc_read_buffer_sync(nandc, true);
> >> +
> >> for (i = 0; i < cw_cnt; i++) {
> >> u32 flash = le32_to_cpu(nandc->reg_read_buf[i]);
> >> > Thanks,
> > Miquèl
>

Cheers,
Miquèl