Hi Boris,
>
> Re: [PATCH v3 2/4] mtd: rawnand: Add Macronix MX25F0A NAND controller
>
> On Tue, 18 Jun 2019 08:14:36 +0200
> Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx> wrote:
>
> > > > > > >
> > > > > > > How to make all #CS keep high for NAND to enter
> > > > > > > low-power standby mode if driver don't use
"legacy.select_chip()"
> > > ?
> > > > > >
> > > > > > See commit 02b4a52604a4 ("mtd: rawnand: Make ->select_chip()
> > > optional
> > > > > > when ->exec_op() is implemented") which states:
> > > > > >
> > > > > > "When [->select_chip() is] not implemented, the core
is
> > > assuming
> > > > > > the CS line is automatically asserted/deasserted by the
driver
> > > > > > ->exec_op() implementation."
> > > > > >
> > > > > > Of course, the above is right only when the controller driver
> > > supports
> > > > > > the ->exec_op() interface.
> > > > >
> > > > > Currently, it seems that we will get the incorrect data and
error
> > > > > operation due to CS in error toggling if CS line is controlled
in
> > > > > ->exec_op().
>
> Oh, and please provide the modifications you added on top of this patch.
> Right now we're speculating on what you've done which is definitely not
> an efficient way to debug this sort of issues.
The patch is to add in beginning of ->exec_op() to control CS# low and
before return from ->exec_op() to control CS# High.
i.e,.
static in mxic_nand_exec_op( )
{
cs_to_low();
cs_to_high();
return;
}
But for nand_onfi_detect(),
it calls nand_read_param_page_op() and then nand_read_data_op().
mxic_nand_exec_op() be called twice for nand_onfi_detect() and
driver will get incorrect ONFI parameter table data from
nand_read_data_op().
thanks & best regards,
Mason
CONFIDENTIALITY NOTE:
This e-mail and any attachments may contain confidential information
and/or personal data, which is protected by applicable laws. Please be
reminded that duplication, disclosure, distribution, or use of this e-mail
(and/or its attachments) or any part thereof is prohibited. If you receive
this e-mail in error, please notify us immediately and delete this mail as
well as its attachment(s) from your system. In addition, please be
informed that collection, processing, and/or use of personal data is
prohibited unless expressly permitted by personal data protection laws.
Thank you for your attention and cooperation.
Macronix International Co., Ltd.
=====================================================================
============================================================================
CONFIDENTIALITY NOTE:
This e-mail and any attachments may contain confidential information and/or personal data, which is protected by applicable laws. Please be reminded that duplication, disclosure, distribution, or use of this e-mail (and/or its attachments) or any part thereof is prohibited. If you receive this e-mail in error, please notify us immediately and delete this mail as well as its attachment(s) from your system. In addition, please be informed that collection, processing, and/or use of personal data is prohibited unless expressly permitted by personal data protection laws. Thank you for your attention and cooperation.
Macronix International Co., Ltd.
=====================================================================
