Re: [PATCH v2 1/2] mtd: rawnand: qcom: Fix broken erase in misc_cmd_type in exec_op

[Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>]

On Wed, Mar 27, 2024 at 05:51:31PM +0100, Miquel Raynal wrote:
> Hi,
> 
> ansuelsmth@gmail.com wrote on Wed, 27 Mar 2024 16:20:58 +0100:
> 
> > On Tue, Mar 26, 2024 at 12:55:12PM +0530, Manivannan Sadhasivam wrote:
> > > On Mon, Mar 25, 2024 at 11:30:47AM +0100, Christian Marangi wrote:  
> > > > misc_cmd_type in exec_op have multiple problems. With commit a82990c8a409
> > > > ("mtd: rawnand: qcom: Add read/read_start ops in exec_op path") it was
> > > > reworked and generalized but actually broke the handling of the
> > > > ERASE_BLOCK command.
> > > > 
> > > > Additional logic was added to the erase command cycle without clear
> > > > explaination causing the erase command to be broken on testing it on
> > > > a ipq806x nandc.
> > > > 
> > > > Fix the erase command by reverting the additional logic and only adding
> > > > the NAND_DEV0_CFG0 additional call (required for erase command).
> > > > 
> > > > Fixes: a82990c8a409 ("mtd: rawnand: qcom: Add read/read_start ops in exec_op path")
> > > > Cc: stable@vger.kernel.org
> > > > Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
> > > > ---
> > > > Changes v2:
> > > > - Split this and rework commit description and title
> > > > 
> > > >  drivers/mtd/nand/raw/qcom_nandc.c | 5 ++---
> > > >  1 file changed, 2 insertions(+), 3 deletions(-)
> > > > 
> > > > diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
> > > > index b079605c84d3..19d76e345a49 100644
> > > > --- a/drivers/mtd/nand/raw/qcom_nandc.c
> > > > +++ b/drivers/mtd/nand/raw/qcom_nandc.c
> > > > @@ -2830,9 +2830,8 @@ static int qcom_misc_cmd_type_exec(struct nand_chip *chip, const struct nand_sub
> > > >  	nandc_set_reg(chip, NAND_EXEC_CMD, 1);
> > > >  
> > > >  	write_reg_dma(nandc, NAND_FLASH_CMD, instrs, NAND_BAM_NEXT_SGL);
> > > > -	(q_op.cmd_reg == OP_BLOCK_ERASE) ? write_reg_dma(nandc, NAND_DEV0_CFG0,
> > > > -	2, NAND_BAM_NEXT_SGL) : read_reg_dma(nandc,
> > > > -	NAND_FLASH_STATUS, 1, NAND_BAM_NEXT_SGL);
> > > > +	if (q_op.cmd_reg == OP_BLOCK_ERASE)
> > > > +		write_reg_dma(nandc, NAND_DEV0_CFG0, 2, NAND_BAM_NEXT_SGL);  
> > > 
> > > So this only avoids the call to, 'read_reg_dma(nandc, NAND_FLASH_STATUS, 1,
> > > NAND_BAM_NEXT_SGL)' if q_op.cmd_reg != OP_BLOCK_ERASE. But for q_op.cmd_reg ==
> > > OP_BLOCK_ERASE, the result is the same.
> > > 
> > > I'm wondering how it results in fixing the OP_BLOCK_ERASE command.
> > > 
> > > Can you share the actual issue that you are seeing? Like error logs etc...
> > >  
> > 
> > Issue is that nandc goes to ADM timeout as soon as a BLOCK_ERASE is
> > called. BLOCK_ERASE operation match also another operation from MTD
> > read. (parser also maps to other stuff)
> > 
> > I will be away from the testing board for 7-10 days so I can't provide
> > logs currently.
> 
> So, shall we wait for additional logs from Christian or shall I merge
> the two-patches series? I'm not sure what's the status anymore.
> 

TBH, I don't know how OP_BLOCK_ERASE can fail without this change. But I can
clearly see the 2 patches required for OP_RESET_DEVICE command. But merging the
patches as it is doesn't look good to me.

So I think if Christian can club the two patches into 1 as like v1 and reword
the commit message and subject to reflect the fact that OP_RESET_DEVICE command
is being fixed would work for me.

- Mani

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