[PATCH] imx8m: soc: cope with existing optee node

[Peng Fan]

> Subject: [PATCH] imx8m: soc: cope with existing optee node
> 
> On i.MX8M SoCs, the /firmware/optee Devicetree node is created just
> before booting the OS when OP-TEE is found running. If the node
> already exists, this results in an error, which prevents the OS to boot:
> 
>   Could not create optee node.
>   ERROR: system-specific fdt fixup failed: FDT_ERR_EXISTS
>    - must RESET the board to recover.
> 
>   failed to process device tree
> 
> On the i.MX8M systems where CONFIG_OF_SYSTEM_SETUP is defined,
> the
> ft_add_optee_node() function is called before booting the OS. It will
> create the OP-TEE Devicetree node and populate it with reserved
> memory informations gathered at runtime.
> 
> On on most i.MX8M systems the Devicetree is built with an optee node
> if CONFIG_OPTEE is defined. This node is indeed necessary for
> commands and drivers communicating with OP-TEE, even before
> attempting OS boot.
> 
> The aforementioned issue can happen on the Compulab IOT-GATE-
> iMX8, which is the only in-tree i.MX8M system where both
> CONFIG_OPTEE and CONFIG_OF_SYSTEM_SETUP are defined (see the
> imx8mm-cl-iot-gate* defconfigs).
> 
> Deal with an existing optee node gracefully at runtime to fix this issue.
> 
> Signed-off-by: Vincent Stehlé <vincent.stehle at arm.com>
> Cc: Stefano Babic <sbabic at denx.de>
> Cc: Fabio Estevam <festevam at gmail.com>
> Cc: Tom Rini <trini at konsulko.com>
> Cc: Tim Harvey <tharvey at gateworks.com>

Reviewed-by: Peng Fan <peng.fan at nxp.com>