[PATCH] dm: Add docs to explain how to enable DM_SERIAL for a board

[Fabio Estevam]

Hi Simon,

On Tue, Mar 15, 2022 at 2:54 AM Simon Glass <sjg at chromium.org> wrote:

> +For example, on iMX6::
> +
> +   lpuart3: serial at 5a090000 {
> +      compatible = "fsl,imx8qm-lpuart";

I found this part confusing as i.MX6 does not have lpuart.

> +For example, on iMX6, put this in your xxx-u-boot.dtsi file::
> +
> +   &pd_dma {
> +      u-boot,dm-pre-proper;
> +   };
> +
> +   &pd_dma_lpuart3 {
> +      u-boot,dm-pre-proper;

Same here, these pd_dma and pd_dma_lpuart3 nodes do not exist for i.MX6.