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* [PATCH 0/4] Make i.MX8M Nano OCOTP work as accessing controller
@ 2025-01-30 13:00 Alexander Stein
  2025-01-30 13:00 ` [PATCH 1/4] dt-bindings: nvmem: imx-ocotp: Add i.MX8M Nano access controller definitions Alexander Stein
                   ` (4 more replies)
  0 siblings, 5 replies; 18+ messages in thread
From: Alexander Stein @ 2025-01-30 13:00 UTC (permalink / raw)
  To: Rob Herring, Krzysztof Kozlowski, Conor Dooley, Shawn Guo,
	Sascha Hauer, Pengutronix Kernel Team, Fabio Estevam,
	Srinivas Kandagatla
  Cc: Alexander Stein, devicetree, imx, linux-arm-kernel, linux-kernel

Hi,

inspired by [1] this adds the accessing controller feature to i.MX8M Nano.
The OCOTP eFuse has bits which can disable particular peripherals, such as
GPU, MIPI-DSI oder USB.

In OCOTP driver, the nodes under "/" will be iterated, and checked
if property "#access-controllers" exsits. If not allow access, detach
the node.

I successfully used this on a i.MX8M Nano DualLite which has GPU disabled.
Without this patchset the default DT completly freezes the SoC if GPU
is accessed.
Using this patchset the GPU is disabled without any DT modification from
bootloader:
> imx_ocotp 30350000.efuse: /soc@0/gpu@38000000: disabled by fuse, device driver will not be probed

Adding the other i.MX8M SoCs is straight forward.

Best regards,
Alexander

[1] https://lore.kernel.org/all/20250121-imx-ocotp-v6-0-76dab40e13db@nxp.com/

Alexander Stein (4):
  dt-bindings: nvmem: imx-ocotp: Add i.MX8M Nano access controller
    definitions
  nvmem: imx-ocotp: Sort header alphabetically
  nvmem: imx-ocotp: Support accessing controller for i.MX8M Nano
  arm64: dts: imx8mn: Add access-controller references

 arch/arm64/boot/dts/freescale/imx8mn.dtsi    |   8 ++
 drivers/nvmem/Kconfig                        |   3 +
 drivers/nvmem/imx-ocotp.c                    | 107 ++++++++++++++++++-
 include/dt-bindings/nvmem/fsl,imx8mn-ocotp.h |  16 +++
 4 files changed, 132 insertions(+), 2 deletions(-)
 create mode 100644 include/dt-bindings/nvmem/fsl,imx8mn-ocotp.h

-- 
2.34.1


^ permalink raw reply	[flat|nested] 18+ messages in thread

end of thread, other threads:[~2025-02-05 17:03 UTC | newest]

Thread overview: 18+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-01-30 13:00 [PATCH 0/4] Make i.MX8M Nano OCOTP work as accessing controller Alexander Stein
2025-01-30 13:00 ` [PATCH 1/4] dt-bindings: nvmem: imx-ocotp: Add i.MX8M Nano access controller definitions Alexander Stein
2025-01-30 16:32   ` Frank Li
2025-01-30 18:47   ` Conor Dooley
2025-01-30 13:00 ` [PATCH 2/4] nvmem: imx-ocotp: Sort header alphabetically Alexander Stein
2025-01-30 16:33   ` Frank Li
2025-01-30 13:01 ` [PATCH 3/4] nvmem: imx-ocotp: Support accessing controller for i.MX8M Nano Alexander Stein
2025-01-30 16:42   ` Frank Li
2025-01-31 13:54     ` Alexander Stein
2025-01-31 16:06       ` Frank Li
2025-02-05  6:51         ` Alexander Stein
2025-02-05 16:43           ` Frank Li
2025-02-05 17:02             ` Frank Li
2025-01-31  7:20   ` Krzysztof Kozlowski
2025-01-31 13:50     ` Alexander Stein
2025-01-31 14:07       ` Krzysztof Kozlowski
2025-01-30 13:01 ` [PATCH 4/4] arm64: dts: imx8mn: Add access-controller references Alexander Stein
2025-01-30 23:38 ` [PATCH 0/4] Make i.MX8M Nano OCOTP work as accessing controller Rob Herring (Arm)

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