STM32F76x: Add support of dual bank flash mode

[bcostm]

Description

This PR adds support of Dual Bank flash mode on NUCLEO_F767ZI and DISCO_F769NI platforms.

Fixes Issue #6955

Tested OK using tests-mbed_drivers-flashiap and tests-mbed_hal-flash tests.

Note
The Single Bank mode is selected by default on these 2 boards.
To enable the Dual Bank mode you have to:

• enable the FLASH_DUAL_BANK configuration using a json file
• enable the Dual Bank in the option bytes using STLink-Utility software (uncheck the nDBANK box)
• upgrade the STLink fw on the board to the latest version (V2.J30.M21 as of today)

Uncyclo page:
https://os.mbed.com/teams/ST/wiki/How-to-enable-flash-dual-bank

Pull request type

[X] Fix
[ ] Refactor
[ ] New target
[ ] Feature
[ ] Breaking change

[0xc0170]

@dhwalters423 Please review. Does this address the issue you reported?

[0xc0170]

@SenRamakri with the latest changes to the error handling, can you review this error handling

[jeromecoutant]

Code review done.
Tests also verified on my side with single and dual configuration.

[dhwalters423]

Looks great! Thank you!

I was able to test this by cherry picking commit into Mbed OS 5.7.4, and running Simple Cloud Client 1.3 for the NUCLEO F767ZI: https://os.mbed.com/users/dwaltersARM/code/example-Ethernet-mbed-Cloud-connect/

I used the following sector layout for SOTP/RoT:
"app.sotp-section-1-address": "(0x081C0000)",
"app.sotp-section-1-size" : "(1281024)",
"app.sotp-section-2-address": "(0x081E0000)",
"app.sotp-section-2-size" : "(1281024)"
(sectors 22 and 23 on the 767ZI)

The RoT was inserted and preserved correctly while stored in those sectors.

We should be sure to document the process with ST-Link utility to switch the platforms into Dual Bank mode on the platform page: https://os.mbed.com/platforms/ST-Nucleo-F767ZI/

[bcostm]

Thanks for the testing.

We should be sure to document the process with ST-Link utility to switch the platforms into Dual Bank mode

I will explain this in a WIKI page (in ST team area on mbed.org) as soon this PR is merged.

[0xc0170]

/morph build

[mbed-ci]

Build : SUCCESS

Build number : 2265
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/7088/

Triggering tests

/morph test
/morph uvisor-test
/morph export-build
/morph mbed2-build

[cmonr]

Halting CI builds until RC3 PRs are completed. Will resume after.

[0xc0170]

/morph test
/morph export-build

[mbed-ci]

Exporter Build : SUCCESS

Build number : 1901
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/exporter/7088/

[mbed-ci]

Test : SUCCESS

Build number : 2062
Test logs :http://mbed-os-logs.s3-website-us-west-1.amazonaws.com/?prefix=logs/7088/2062

[cmonr]

Looks good!

[bcostm]

FYI

https://os.mbed.com/teams/ST/wiki/How-to-enable-flash-dual-bank

[mbed-ci]

Exporter Build : FAILURE

Build number : 1960
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/exporter/7088/