Starting Tiny OS Development With HiFive1

[mhamrick (Meadhbh Hamrick)]

i actually did this for a customer. (code that runs in RAM and writes FLASH.) Megan describes the fespi driver in this post from way back when:

How can I debug the HiFive board by JTAG?

Hi Huangwanneng, suggest that you first take a look at the RISC-V Debug Spec: And then you can look at the implementation of OpenOCD here: In particular, when the program is loaded to the SPI Flash, GDB’s load command examines the ELF file, sees that it linked in the Flash region, then requests OpenOCD to uses the appropriate driver to program the SPI Flash. For Freedom E platforms, that’s the fespi driver that we’ve also added to OpenOCD. OpenOCD is causing the processor to execute li…

i was also able to run TINY BASIC on the HiFive1, but still trying to figure out how to modify it to allow me to do GPIO twiddling.