On Wednesday 01 February 2023 09:17:15 Michael Walle wrote: > > > > When DM_SERIAL is enabled, the device-tree property dm-pre-reloc is > > > > required to boot over UART with kwboot. Enable this in a Kirkwood > > > > common u-boot dtsi. > > > > > > My (dev) board unfortunately, have a bootloader which can't boot over > > > serial. > > > > This is feature of Marvell BootROM and does not require any special from > > Bootloader. So you should be able to boot over UART (if you have > > accessible pins). > > I know, but there are known versions ob the bootrom where uart boot > isn't supported (correctly).
I heard about it... maybe it is a bug in client software (kwboot)? I do not have such board if you are interested in it I could try to send some details how to debug it. > I also have another board which can boot > over uart. But thats in daily use ;) > > > > Could you elaborate that a bit more? Why is this required for > > > uart boot? kwboot will talk with the bootrom why does u-boot need > > > anything? Or will there just be no output until the uart is > > > initialized? > > > > On mvebu/armada boards this dm-pre-reloc is required to ensure that DT > > nodes are present in SPL DTB file. Otherwise build process drop all > > non-pre-realoc nodes from SPL version of DTB file. And because SPL use > > DM serial, it is required to have uart DT nodes in DTB file. Btw, same > > problem is with SPI in SPL. > > > > But... kirkwood does not use SPL, so I do not know what is reason for > > this here. > > Yes thats what puzzled me, too. > > > > > > > > > Signed-off-by: Tony Dinh <mibo...@gmail.com> > > > > --- > > > > > > > > arch/arm/dts/kirkwood-u-boot.dtsi | 7 +++++++ > > > > 1 file changed, 7 insertions(+) > > > > create mode 100644 arch/arm/dts/kirkwood-u-boot.dtsi > > > > > > Is this new? AFAIK only <boardname>-u-boot.dtsi is included > > > automatically. > > > > It is not new, Tom wrote about it quite ago: > > https://lore.kernel.org/u-boot/20220802121113.GG1146598@bill-the-cat/ > > Thats relatively new for someone not following the u-boot > development that closely ;) Thanks for the pointer. > > -michael >