STM32U585 / B-U585I-IOT02A: Can't enable GPIOI via RCC_AHB2ENR1

[_MJung.5]

Hello,

I am trying to access the MX25LM NOR-Flash chip on the B-U585I-IOT02A board via OCTOSPI2. The nCS pin is connected to PI5. However, attempting to enabe the peripheral clock for IO port I by setting Bit 8 (GPIOIEN) of register RCC_AHB2ENR1 fails (I.e. bit 8 remains at value 0). For all other IO ports (A-H) it works as expected.

Any idea what might cause this behaviour?

Note: The code is running as a device driver under the Apache NuttX RTOS in the non-secure world. TrustedFirmware-M (from STM32CubeU5 v1.0.2) is running on the secure side.

Any help is very appreciated.

Bye,

Michael

[_MJung.5 · Accepted solution]

Hello again,

turns out that the STM32CubeU5 version of TrustedFirmware-M does not configure IO Port I as non-secure, as it does for ports A-H. Fixing this resolves the issue for me.

Bye,

Michael

[Amel NASRI]

Hi @MJung.5,

I'm coming back to this question:

1. first to thank you for sharing your findings
2. secondly to check with you what you did exactly to fix the issue: which file(s) did you updated exactly please? This is helpful to fix permanently the issue.

-Amel