UART on i.MX7D A7 core

[emilianocostagl]

Hello people,

Has anybody tried to get the UART working on the Cortex-A7 core of the i.MX7D device, running a baremetal program?

I have started from the FreeRTOS_BSP_1.0.1_iMX7D project, changing the start-up code to run on one of the A7, but I don't seem to be able to access any of the UART interfaces (even from the debugger, the UART registers are either 0 or unreadable). I don't think the problem is in the MMU, because I am configuring it to access the full AIPS ranges.

By the way, on the FreeRTOS_BSP_1.0.1_iMX7D project, I believe the base address of the UART2 (UART2_BASE) is wrong: in MCIMX7D_M4.h it is defined as 0x30890000, while, according to the reference manual, it should be 0x30870000.

Thanks,

-Emiliano

[igorpadykov]

Hi Emiliano

right, correct UART2 address is 0x30870000, problems with register access may be

due to clock gating, this is described in sect.5.2.7.3 CCGR Interface i.MX7D Reference Manual

Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------