On Wed, May 6, 2020 at 4:56 PM Gregory Nutt <spudan...@gmail.com> wrote: > > In arch/arm/src/stm32/hardware/stm32_dma_v1.h, I have to add DMA > > channel mappings of the form: > > > > # define DMACHAN_ADC1 STM32_DMA1_CHAN1 > > > > for the (new) case of CONFIG_STM32_STM32G47XX. > > > > How / where can I find the names and values that should be defined? > > Probably in the data sheet rather that the user manual
I am beginning to see what's going on here, but I don't claim to understand how this works yet. The STM32G474 has two DMA controllers, DMA1 and DMA2, and a separate thing called DMAMUX that sits in front of them and routes DMA requests between peripherals and the DMA controllers. And I think that unlike another part, say STM32F334 for example, which has a fixed mapping from peripherals to a particular DMA channel number, on the STM32G474 it looks like the routing is selected by the DMAMUX based on what's going on at that moment. They say the chip has 115 DMA request lines! Part of the reason for my interest in this chip is that it has a lot of exotic stuff like this, that should make it possible to squeeze a lot of performance out! But I think this is a problem for another day. Right now, I am trying to get my code to build, so that I can start testing the initial stages of the bring-up logic. DMA will be important, later. Nathan
