Background
I’m building a test fixture based on the TM4C that will be used to automate certain functionality for TI’s mmWave based platforms. The main communication between the test fixture (TM4C) and mmWave device is UART. With that said, before I dive in, I wanted to verify a couple assumptions with regard to TivaWare, DriverLib, and the relationship with TI-RTOS.
That’s quite a broad topic, so to narrow the scope, the focus of this question will be in relation to UART specifically.
Thought Process
At a high level, I see three libraries at play;
- TivaWare SDK (DriverLib): For example C:\ti\tivaware_c_series_2_1_4_178\driverlib
- TI-RTOS-TivaC (DriverLib rebuilt for RTOS). For example: C:\ti\tirtos_tivac_2_16_00_08\products\TivaWare_C_Series-2.1.1.71b\driverlib
- TI-RTOS Drivers. For example: C:\ti\tirtos_tivac_2_16_00_08\products\tidrivers_tivac_2_16_00_08\packages\ti\drivers
Question:
Is it correct to say, the standard DriverLib library from TivaWare is not thread safe. For this reason, a subset of drivers are provided within TI-RTOS-TivaC, which is thread safe. These are the drivers found within \ti\drivers, for example ti\drivers\UART.h?
In terms of DriverLib, maybe the bundled version found within tirtos_tivac (C:\ti\tirtos_tivac_2_16_00_08\products\TivaWare_C_Series-2.1.1.71b\driverlib) is the one the developer should use, instead of reaching directly into C:\ti\tivaware? I'll have to diff the DriverLib version found within TI-RTOS, versus the standard TivaWare DriverLib, to see if there's any differences.
So in summary, when developing an application within TI-RTOS for the TM4C, which drivers are you allowed to use. Should you only try to exclusively use the subset of RTOS drivers, or is it fine to directly use DriverLib drivers? Also, kind of along the same lines, do you omit the ROM_ or MAP_ directives in general, as the RTOS probably internally maps these already?
Example:
To bring things full circle, I figured an example would be best.
Imagine you are leveraging DMA to facilitate serial comms over UART. One option provided within DriverLib’s implementation of uDMA, is to setup a ping-pong style Control Mode via UDMA_MODE_PINGPONG, using both primary and secondary buffers for storage.
However, TI-RTOS for Tiva does not have such functionality in their UARTivaDMA driver, so maybe that’s a case where you’re on your own?
I think once I understand the basic concept of what can and can’t be used, then the rest of the puzzle pieces should fall into place.
Thanks!
