Re: [PATCH v2 1/2] efi: SPI NOR flash support

[Michael Lawnick]

Am 11.02.2021 um 15:04 schrieb Heinrich Schuchardt:
> On 11.02.21 13:50, Michael Lawnick wrote:
> > Hi,
> > Several boot parameters are stored in our SPI flash to configure the
> > systems for different use cases.
>
> I still do not understand why you need access in GRUB. You can read and
> write the SPI flash in U-Boot on your embedded system.

In our latest system we get U-Boot from vendor. We try to change nothing
in it. To execute our boot management we let start GRUB as an EFI app.
The boot management needs configuration information which depends on
customer deployment scenario saved in SPI flash. It is our boot
management S/W which uses the EFI_SPI_NOR interface.

> Maybe you could provide a short example script showing how the new
> command would fit into the GRUB boot flow.

The spi_nor command is more intended as an example application and for
test, not intended for real use. I have no problem to deactivate it by
default (put it to separate config module) or even completely remove it.
My real point is the driver to abstract away the H/W and take EFI into
use if available.

KR
Michael