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

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

Overall fine!

But:

+++ b/arch/arm/dts/juno-motherboard.dtsi

(...)

•   bus@8000000 {
  

•           compatible = "simple-bus";
  

(...)

•           motherboard-bus@8000000 {
  

•                   compatible = "arm,vexpress,v2p-p1", "simple-bus";
  

(...)

•                   flash@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