On Wednesday 01 February 2023 08:53:55 Michael Walle wrote:
Hi Tony,
Am 2023-02-01 02:11, schrieb Tony Dinh:
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).
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.
Signed-off-by: Tony Dinh mibodhi@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/