[PATCH v3 0/5] Expose RPi4's bootloader configuration

Srinivas Kandagatla srinivas.kandagatla at linaro.org
Mon Jan 18 11:50:20 EST 2021



On 12/01/2021 14:23, Nicolas Saenz Julienne wrote:
> Soon to be released versions of RPi4's firmware will take of care
> passing their bootloader's configuration[1] to the OS by copying it into
> memory and creating a reserved memory node in the board's DT. By
> modeling this reserved memory node as an nvmem device using
> 'nvmem-rmem', which this series introduces, user-space applications will
> be able to query this information through nvmem's sysfs interface.
> 
> An alternative approach, less nice IMO, would be to create a
> platform-specific 'soc' driver.
> 
> Regards,
> Nicolas
> 
> [1] https://www.raspberrypi.org/documentation/hardware/raspberrypi/bcm2711_bootloader_config.md
> 
> ---
> 
> Changes since v2:
>   - Fix DT bingins
> 
> Changes since v1:
>   - Avoid the reserved-memory indirection by integrating the nvmem driver
>     into the reserved memory node.
> 
> Nicolas Saenz Julienne (5):
>    dt-bindings: nvmem: Add bindings for rmem driver
>    nvmem: Add driver to expose reserved memory as nvmem
>    ARM: dts: bcm2711: Add reserved memory template to hold firmware
>      configuration
>    arm64: defconfig: Enable nvmem's rmem driver
>    ARM: multi_v7_defconfig: Enable nvmem's rmem driver
> 


Thanks Applied (1/5) and (2/5), rest of patches should go via arm-soc tree!

--srini

>   .../devicetree/bindings/nvmem/rmem.yaml       | 49 ++++++++++
>   arch/arm/boot/dts/bcm2711-rpi-4-b.dts         | 17 ++++
>   arch/arm/configs/multi_v7_defconfig           |  1 +
>   arch/arm64/configs/defconfig                  |  1 +
>   drivers/nvmem/Kconfig                         |  8 ++
>   drivers/nvmem/Makefile                        |  2 +
>   drivers/nvmem/rmem.c                          | 97 +++++++++++++++++++
>   drivers/of/platform.c                         |  1 +
>   8 files changed, 176 insertions(+)
>   create mode 100644 Documentation/devicetree/bindings/nvmem/rmem.yaml
>   create mode 100644 drivers/nvmem/rmem.c
> 



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