NetworkInterface connect call hard faults when PSA is enabled on Cypress targets

[linlingao]

Description of defect

Pelion example crashes when PSA is enabled in mbed_app.json during NetworkInterface connect().

NetworkInterface connect call triggers init_sdio_bus(), which calls cybsp_get_wifi_sdio_obj(). The sdio_obj retrieved is not initialized. This sdio_obj is initialized in cybsp_init(), but cybsp_init is called only when PSA is disabled, in mbed_overrides.c

#if !defined(TARGET_PSA)
/* Set up the device based on configurator selections /
cybsp_init();
/
* Init the us Ticker here to avoid imposing on the limited stack space of the idle thread.
* This also allows the first call to sleep to occur faster.
*/
us_ticker_init();
#endif

I'm not sure what the rationale is behind this guard. PSA should have nothing to do with cybsp_init and us_ticker_init.

Target(s) affected by this defect ?

CY8CPROTO_062_4343W and possibly other similar targets

Toolchain(s) (name and version) displaying this defect ?

GCC_ARM and possibly all toolchains

What version of Mbed-os are you using (tag or sha) ?

5.14.1 and possibly earlier releases

What version(s) of tools are you using. List all that apply (E.g. mbed-cli)

Shouldn't matter

How is this defect reproduced ?

Build mbed-os-example-pelion for cy8cproto_062_4343w with this PR:
ARMmbed/mbed-os-example-pelion#37

The application should throw an exception.

[linlingao]

@ARMmbed/team-cypress @maclobdell

[ciarmcom]

Internal Jira reference: https://jira.arm.com/browse/MBOCUSTRIA-1950

[maclobdell]

Thanks Lin!

A key aspect of this issue that needs clarification from the security experts (or maybe we need to find where it is documented) -

What exactly are all the implications, dependencies, requirements, etc for using the TARGET_PSA macro?

In some cases it seems that this macro enables the use of PSA Crypto APIs,
In other cases it seems to indicate that a secure partition manager is enabled.
In this case for Cypress, it seems they are using the macro to designate that the Cortex M0+ and not the Cortex M4 will handle some of the initialization.

[ifyall]

@linlingao , I have filed an internal ticket with Cypress to get the extraneous #if !defined(TARGET_PSA) removed.

Thank you,

Ian

[morser499]

Changes for this are included in #11800

[maclobdell]

@linlingao - please confirm you are okay to close this issue now.