[PATCH v7 08/31] arm: vexpress: Add a devicetree files for juno

[Linus Walleij]

On Tue, Dec 7, 2021 at 1:12 AM Simon Glass <sjg at chromium.org> wrote:

> Sync these file, obtained from Linux v5.15.
>
> Add a note for the maintainer, and SPDX lines where they are missing.
> The added lines are:
>
>    SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
>
> Note, this matches the text in those files, but is not the same as the
> GPL-2.0 of some files.
>
> [1] https://releases.linaro.org/android/reference-lcr/juno/7.1-17.05/
>
> Signed-off-by: Simon Glass <sjg at chromium.org>

Overall fine!

But:

> +++ b/arch/arm/dts/juno-motherboard.dtsi
(...)
> +       bus at 8000000 {
> +               compatible = "simple-bus";
(...)
> +               motherboard-bus at 8000000 {
> +                       compatible = "arm,vexpress,v2p-p1", "simple-bus";
(...)
> +                       flash at 0 {
> +                               /* 2 * 32MiB NOR Flash memory mounted on CS0 */
> +                               compatible = "arm,vexpress-flash", "cfi-flash";
> +                               reg = <0 0x00000000 0x04000000>;
> +                               bank-width = <4>;
> +                               /*
> +                                * Unfortunately, accessing the flash disturbs
> +                                * the CPU idle states (suspend) and CPU
> +                                * hotplug of the platform. For this reason,
> +                                * flash hardware access is disabled by default.
> +                                */
> +                               status = "disabled";
> +                               partitions {
> +                                       compatible = "arm,arm-firmware-suite";
> +                               };
> +                       };

This should not be marked "disabled" in U-boot. The boot loader is not
using some CPU idle states and hotplug but may be very interested
in accessing the flash.

Yours,
Linus Walleij