Re: [PATCH 2/2] mtd: spi-nor: intel-spi: fix forced writable option

From: Daniel Walker (danielwa)
Date: Tue Jun 02 2020 - 12:36:42 EST


On Thu, May 28, 2020 at 03:55:21PM +0000, Jinhua Wu (jinhwu) wrote:
> On 2020/5/28, 11:48 PM, "Jinhua Wu" <jinhwu@xxxxxxxxx> wrote:
> Hi Vignesh,
> BIOS just locked down parts of flash (such as, code region), others are still
> writeable. Once the SPI locked down,it can't be override unless platfrom reset
> and set WPD (write protect disable) will fail, so ispi->writeable will always
> be 0, then the driver will always make the whole flash read only, even if we
> have set the parameter writable = 1.
> Now the flash is totally not writeable, just part of it is read only. Why not making
> 'writeable' working when explicitly enabled?
>
> >On 2020/5/28, 7:02 PM, "Vignesh Raghavendra" <vigneshr@xxxxxx> wrote:
> > On 18/05/20 11:29 pm, Daniel Walker wrote:
> > > This option currently doesn't work as expected. If the BIOS has this
> > > flash as read-only there is no way to change this thru the driver.
> > > There is a parameter which allows the flash to become writable with the
> > > "writable" option to the module, but it does nothing if the BIOS has it
> > > set to read-only.
> > >
> > > I would expect this option would make the flash writable regardless of
> > > the BIOS settings. This patch changes this option so the BIOS setting
> > > doesn't stop the writable option from enabling read write on the flash.
> > >
> >
> > I am confused you say "If the BIOS has this flash as read-only there is
> > no way to change this thru the driver", so is it possible to override
> > BIOS setting? If yes, where is the code in the driver?
> >
> > What happens if BIOS is set to allow writes but writeable is set to 0?
> >
> > Also please send patch series as thread (2/2 in reply to 1/2). You can
> > use tool like git send-email
> >



Vignesh, do you still have concerns about this change ?


Daniel