Re: [PATCH] spi: intel: Add protected and locked attributes

[Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>]

On Wed, Oct 09, 2024 at 09:12:02AM +0300, Mika Westerberg wrote:
> From: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
> 
> The manufacturing access to the PCH/SoC SPI device is traditionally
> performed via userspace driver accessing registers via /dev/mem but due
> to security concerns /dev/mem access is being much restricted, hence the
> reason for utilizing dedicated Intel PCH/SoC SPI controller driver,
> which is already implemented in the Linux kernel.
> 
> Intel PCH/SoC SPI controller protects the flash storage via two
> mechanisms one is the via region protection registers and second via
> BIOS lock. The BIOS locks only the BIOS regions usually 0 and/or 6.
> 
> The device always boots with BIOS lock set, but during manufacturing the
> BIOS lock has to be lifted in order to enable the write access. This can
> be done by passing "writeable=1" in the command line when the driver is
> loaded. This "locked" state is exposed through new sysfs attributes
> (intel_spi_locked, intel_spi_bios_locked).
> 
> Second, also the region protection status is exposed via sysfs attribute
> (intel_spi_protected) as the manufacturing will need the both files in
> order to validate that the device is properly sealed.
> 
> Includes code written by Tamar Mashiah.
> 
> Signed-off-by: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
> Co-developed-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
> Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>

Just learned that Tomas just left Intel so this address is not working
anymore, I'll resend with that updated.