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From: "Daniel Walker (danielwa)" <danielwa@cisco.com>
To: "Jinhua Wu (jinhwu)" <jinhwu@cisco.com>
Cc: Vignesh Raghavendra <vigneshr@ti.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	"xe-linux-external(mailer list)" <xe-linux-external@cisco.com>,
	Tudor Ambarus <tudor.ambarus@microchip.com>,
	Miquel Raynal <miquel.raynal@bootlin.com>,
	Richard Weinberger <richard@nod.at>,
	"linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Mika Westerberg <mika.westerberg@linux.intel.com>
Subject: Re: [PATCH 2/2] mtd: spi-nor: intel-spi: fix forced writable option
Date: Tue, 2 Jun 2020 16:36:31 +0000	[thread overview]
Message-ID: <20200602163631.GH23028@zorba> (raw)
In-Reply-To: <190F24BF-EE4C-4C40-9101-C0AE6C9CEF53@cisco.com>

On Thu, May 28, 2020 at 03:55:21PM +0000, Jinhua Wu (jinhwu) wrote:
> On 2020/5/28, 11:48 PM, "Jinhua Wu" <jinhwu@cisco.com> 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@ti.com> 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

      reply	other threads:[~2020-06-02 16:36 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-18 17:59 [PATCH 2/2] mtd: spi-nor: intel-spi: fix forced writable option Daniel Walker
2020-05-28 11:01 ` Vignesh Raghavendra
2020-05-28 15:55   ` Jinhua Wu (jinhwu)
2020-06-02 16:36     ` Daniel Walker (danielwa) [this message]

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