On Thu, Sep 21, 2017 at 03:45:28PM +0800, Hanjun Guo wrote:

On 2017/9/21 15:12, Mayuresh Chitale wrote:

quoted

This patch modifies the optee driver to add support for parsing
the conduit method from an ACPI node.

Sorry I didn't involve this earlier, but I think this is a wrong
approach, in ACPI 5.1+ spec, there is a bit in FADT table which
indicates PSCI using SMC or HVC, please see ACPI 6.2 [1],
Table 5-37 Fixed ACPI Description Table ARM Boot Architecture Flags.

Can we just use that to get the conduit method for optee driver too?

[1]: http://www.uefi.org/sites/default/files/resources/ACPI_6_2.pdf

It is just not a matter of conduit method but also to define how OPTEE
should be detected. It is up to Linaro (who owns OP-TEE) to put forward
a binding at ACPI (ARM) spec level.

We do not define ACPI bindings on a kernel mailing list.

NAK on this patch.

Lorenzo